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[PATCH] hwmon: (ads7828) add support for ADS7830
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Vivien Didelot
Oct 1, 2012, 5:10:04 PM10/1/12
to
From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
The ADS7830 is almost the same chip, except that it does 8-bit sampling.
This patch extends the ads7828 driver to support this device.
Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
Also clean the driver a bit by removing unused macros, and moving
the driver declaration to avoid some function prototypes.
Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
---
Documentation/hwmon/ads7828 | 12 +++-
drivers/hwmon/Kconfig | 7 ++-
drivers/hwmon/ads7828.c | 137 +++++++++++++++++++++++++-------------------
3 files changed, 93 insertions(+), 63 deletions(-)
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828
index 2bbebe6..4366a87 100644
--- a/Documentation/hwmon/ads7828
+++ b/Documentation/hwmon/ads7828
@@ -8,8 +8,15 @@ Supported chips:
Datasheet: Publicly available at the Texas Instruments website :
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * Texas Instruments ADS7830
+ Prefix: 'ads7830'
+ Addresses scanned: I2C 0x48, 0x49, 0x4a, 0x4b
+ Datasheet: Publicly available at the Texas Instruments website:
+ http://focus.ti.com/lit/ds/symlink/ads7830.pdf
+
Authors:
Steve Hardy <sha...@redhat.com>
+ Guillaume Roguez <guillaum...@savoirfairelinux.com>
Module Parameters
-----------------
@@ -24,9 +31,10 @@ Module Parameters
Description
-----------
-This driver implements support for the Texas Instruments ADS7828.
+This driver implements support for the Texas Instruments ADS7828, and ADS7830.
-This device is a 12-bit 8-channel A-D converter.
+The ADS7828 device is a 12-bit 8-channel A/D converter, while the ADS7830 does
+8-bit sampling.
It can operate in single ended mode (8 +ve inputs) or in differential mode,
where 4 differential pairs can be measured.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 83e3e9d..960c8c5 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1060,11 +1060,12 @@ config SENSORS_ADS1015
will be called ads1015.
config SENSORS_ADS7828
- tristate "Texas Instruments ADS7828"
+ tristate "Texas Instruments ADS7828 and compatibles"
depends on I2C
help
- If you say yes here you get support for Texas Instruments ADS7828
- 12-bit 8-channel ADC device.
+ If you say yes here you get support for Texas Instruments ADS7828 and
+ ADS7830 8-channel A/D converters. ADS7828 resolution is 12-bit, while
+ it is 8-bit on ADS7830.
This driver can also be built as a module. If so, the module
will be called ads7828.
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index bf3fdf4..58f28ea 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -1,12 +1,12 @@
/*
- * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC
- * (C) 2007 EADS Astrium
+ * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles
*
- * This driver is based on the lm75 and other lm_sensors/hwmon drivers
+ * Copyright (C) 2007 EADS Astrium
+ * Copyright (C) Steve Hardy <sha...@redhat.com>
+ * Copyright (C) 2012 Savoir-faire Linux Inc.
+ * Guillaume Roguez <guillaum...@savoirfairelinux.com>
*
- * Written by Steve Hardy <sha...@redhat.com>
- *
- * Datasheet available at: http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * For further information, see the Documentation/hwmon/ads7828 file.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -34,14 +34,15 @@
#include <linux/mutex.h>
/* The ADS7828 registers */
-#define ADS7828_NCH 8 /* 8 channels of 12-bit A-D supported */
-#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
-#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
-#define ADS7828_CMD_PD0 0x0 /* Power Down between A-D conversions */
-#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A-D ON */
-#define ADS7828_CMD_PD2 0x08 /* Internal ref ON && A-D OFF */
-#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A-D ON */
-#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+#define ADS7828_NCH 8 /* 8 channels supported */
+#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
+#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
+#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A/D ON */
+#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A/D ON */
+#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+
+/* List of supported devices */
+enum ads7828_chips { ads7828, ads7830 };
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
@@ -57,23 +58,27 @@ module_param(vref_mv, int, S_IRUGO);
/* Global Variables */
static u8 ads7828_cmd_byte; /* cmd byte without channel bits */
-static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
-/* Each client has this additional data */
+/**
+ * struct ads7828_data - client specific data
+ * @hwmon_dev: The hwmon device.
+ * @update_lock: Mutex protecting updates.
+ * @valid: Validity flag.
+ * @last_updated: Last updated time (in jiffies).
+ * @adc_input: ADS7828_NCH samples.
+ * @lsb_resol: Resolution of the A/D converter sample LSB.
+ * @read_channel: Function used to read a channel.
+ */
struct ads7828_data {
struct device *hwmon_dev;
- struct mutex update_lock; /* mutex protect updates */
- char valid; /* !=0 if following fields are valid */
- unsigned long last_updated; /* In jiffies */
- u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH 12-bit samples */
+ struct mutex update_lock;
+ char valid;
+ unsigned long last_updated;
+ u16 adc_input[ADS7828_NCH];
+ unsigned int lsb_resol;
+ s32 (*read_channel)(const struct i2c_client *client, u8 command);
};
-/* Function declaration - necessary due to function dependencies */
-static int ads7828_detect(struct i2c_client *client,
- struct i2c_board_info *info);
-static int ads7828_probe(struct i2c_client *client,
- const struct i2c_device_id *id);
-
static inline u8 channel_cmd_byte(int ch)
{
/* cmd byte C2,C1,C0 - see datasheet */
@@ -97,8 +102,7 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
for (ch = 0; ch < ADS7828_NCH; ch++) {
u8 cmd = channel_cmd_byte(ch);
- data->adc_input[ch] =
- i2c_smbus_read_word_swapped(client, cmd);
+ data->adc_input[ch] = data->read_channel(client, cmd);
}
data->last_updated = jiffies;
data->valid = 1;
@@ -116,8 +120,8 @@ static ssize_t show_in(struct device *dev, struct device_attribute *da,
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ads7828_data *data = ads7828_update_device(dev);
/* Print value (in mV as specified in sysfs-interface documentation) */
- return sprintf(buf, "%d\n", (data->adc_input[attr->index] *
- ads7828_lsb_resol)/1000);
+ return sprintf(buf, "%d\n",
+ (data->adc_input[attr->index] * data->lsb_resol) / 1000);
}
#define in_reg(offset)\
@@ -158,31 +162,13 @@ static int ads7828_remove(struct i2c_client *client)
return 0;
}
-static const struct i2c_device_id ads7828_id[] = {
- { "ads7828", 0 },
- { }
-};
-MODULE_DEVICE_TABLE(i2c, ads7828_id);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver ads7828_driver = {
- .class = I2C_CLASS_HWMON,
- .driver = {
- .name = "ads7828",
- },
- .probe = ads7828_probe,
- .remove = ads7828_remove,
- .id_table = ads7828_id,
- .detect = ads7828_detect,
- .address_list = normal_i2c,
-};
-
/* Return 0 if detection is successful, -ENODEV otherwise */
static int ads7828_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
int ch;
+ bool is_8bit = false;
/* Check we have a valid client */
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA))
@@ -193,20 +179,30 @@ static int ads7828_detect(struct i2c_client *client,
* dedicated register so attempt to sanity check using knowledge of
* the chip
* - Read from the 8 channel addresses
- * - Check the top 4 bits of each result are not set (12 data bits)
+ * - Check the top 4 bits of each result:
+ * - They should not be set in case of 12-bit samples
+ * - The two bytes should be equal in case of 8-bit samples
*/
for (ch = 0; ch < ADS7828_NCH; ch++) {
u16 in_data;
u8 cmd = channel_cmd_byte(ch);
in_data = i2c_smbus_read_word_swapped(client, cmd);
if (in_data & 0xF000) {
- pr_debug("%s : Doesn't look like an ads7828 device\n",
- __func__);
- return -ENODEV;
+ if ((in_data >> 8) == (in_data & 0xFF)) {
+ /* Seems to be an ADS7830 (8-bit sample) */
+ is_8bit = true;
+ } else {
+ dev_dbg(&client->dev, "doesn't look like an "
+ "ADS7828 compatible device\n");
+ return -ENODEV;
+ }
}
}
- strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
+ if (is_8bit)
+ strlcpy(info->type, "ads7830", I2C_NAME_SIZE);
+ else
+ strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
return 0;
}
@@ -223,6 +219,15 @@ static int ads7828_probe(struct i2c_client *client,
goto exit;
}
+ /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
+ if (id->driver_data == ads7828) {
+ data->read_channel = i2c_smbus_read_word_swapped;
+ data->lsb_resol = (vref_mv * 1000) / 4096;
+ } else {
+ data->read_channel = i2c_smbus_read_byte_data;
+ data->lsb_resol = (vref_mv * 1000) / 256;
+ }
+
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
@@ -247,6 +252,25 @@ exit:
return err;
}
+static const struct i2c_device_id ads7828_ids[] = {
+ { "ads7828", ads7828 },
+ { "ads7830", ads7830 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ads7828_ids);
+
+static struct i2c_driver ads7828_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "ads7828",
+ },
+ .probe = ads7828_probe,
+ .remove = ads7828_remove,
+ .id_table = ads7828_ids,
+ .detect = ads7828_detect,
+ .address_list = normal_i2c,
+};
+
static int __init sensors_ads7828_init(void)
{
/* Initialize the command byte according to module parameters */
@@ -255,9 +279,6 @@ static int __init sensors_ads7828_init(void)
ads7828_cmd_byte |= int_vref ?
ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
- /* Calculate the LSB resolution */
- ads7828_lsb_resol = (vref_mv*1000)/4096;
-
return i2c_add_driver(&ads7828_driver);
}
@@ -267,7 +288,7 @@ static void __exit sensors_ads7828_exit(void)
}
MODULE_AUTHOR("Steve Hardy <sha...@redhat.com>");
-MODULE_DESCRIPTION("ADS7828 driver");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles");
MODULE_LICENSE("GPL");
module_init(sensors_ads7828_init);
--
1.7.11.4
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Please read the FAQ at http://www.tux.org/lkml/
The ADS7830 is almost the same chip, except that it does 8-bit sampling.
This patch extends the ads7828 driver to support this device.
Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
Also clean the driver a bit by removing unused macros, and moving
the driver declaration to avoid some function prototypes.
Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
---
Documentation/hwmon/ads7828 | 12 +++-
drivers/hwmon/Kconfig | 7 ++-
drivers/hwmon/ads7828.c | 137 +++++++++++++++++++++++++-------------------
3 files changed, 93 insertions(+), 63 deletions(-)
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828
index 2bbebe6..4366a87 100644
--- a/Documentation/hwmon/ads7828
+++ b/Documentation/hwmon/ads7828
@@ -8,8 +8,15 @@ Supported chips:
Datasheet: Publicly available at the Texas Instruments website :
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * Texas Instruments ADS7830
+ Prefix: 'ads7830'
+ Addresses scanned: I2C 0x48, 0x49, 0x4a, 0x4b
+ Datasheet: Publicly available at the Texas Instruments website:
+ http://focus.ti.com/lit/ds/symlink/ads7830.pdf
+
Authors:
Steve Hardy <sha...@redhat.com>
+ Guillaume Roguez <guillaum...@savoirfairelinux.com>
Module Parameters
-----------------
@@ -24,9 +31,10 @@ Module Parameters
Description
-----------
-This driver implements support for the Texas Instruments ADS7828.
+This driver implements support for the Texas Instruments ADS7828, and ADS7830.
-This device is a 12-bit 8-channel A-D converter.
+The ADS7828 device is a 12-bit 8-channel A/D converter, while the ADS7830 does
+8-bit sampling.
It can operate in single ended mode (8 +ve inputs) or in differential mode,
where 4 differential pairs can be measured.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 83e3e9d..960c8c5 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1060,11 +1060,12 @@ config SENSORS_ADS1015
will be called ads1015.
config SENSORS_ADS7828
- tristate "Texas Instruments ADS7828"
+ tristate "Texas Instruments ADS7828 and compatibles"
depends on I2C
help
- If you say yes here you get support for Texas Instruments ADS7828
- 12-bit 8-channel ADC device.
+ If you say yes here you get support for Texas Instruments ADS7828 and
+ ADS7830 8-channel A/D converters. ADS7828 resolution is 12-bit, while
+ it is 8-bit on ADS7830.
This driver can also be built as a module. If so, the module
will be called ads7828.
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index bf3fdf4..58f28ea 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -1,12 +1,12 @@
/*
- * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC
- * (C) 2007 EADS Astrium
+ * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles
*
- * This driver is based on the lm75 and other lm_sensors/hwmon drivers
+ * Copyright (C) 2007 EADS Astrium
+ * Copyright (C) Steve Hardy <sha...@redhat.com>
+ * Copyright (C) 2012 Savoir-faire Linux Inc.
+ * Guillaume Roguez <guillaum...@savoirfairelinux.com>
*
- * Written by Steve Hardy <sha...@redhat.com>
- *
- * Datasheet available at: http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * For further information, see the Documentation/hwmon/ads7828 file.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -34,14 +34,15 @@
#include <linux/mutex.h>
/* The ADS7828 registers */
-#define ADS7828_NCH 8 /* 8 channels of 12-bit A-D supported */
-#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
-#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
-#define ADS7828_CMD_PD0 0x0 /* Power Down between A-D conversions */
-#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A-D ON */
-#define ADS7828_CMD_PD2 0x08 /* Internal ref ON && A-D OFF */
-#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A-D ON */
-#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+#define ADS7828_NCH 8 /* 8 channels supported */
+#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
+#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
+#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A/D ON */
+#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A/D ON */
+#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+
+/* List of supported devices */
+enum ads7828_chips { ads7828, ads7830 };
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
@@ -57,23 +58,27 @@ module_param(vref_mv, int, S_IRUGO);
/* Global Variables */
static u8 ads7828_cmd_byte; /* cmd byte without channel bits */
-static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
-/* Each client has this additional data */
+/**
+ * struct ads7828_data - client specific data
+ * @hwmon_dev: The hwmon device.
+ * @update_lock: Mutex protecting updates.
+ * @valid: Validity flag.
+ * @last_updated: Last updated time (in jiffies).
+ * @adc_input: ADS7828_NCH samples.
+ * @lsb_resol: Resolution of the A/D converter sample LSB.
+ * @read_channel: Function used to read a channel.
+ */
struct ads7828_data {
struct device *hwmon_dev;
- struct mutex update_lock; /* mutex protect updates */
- char valid; /* !=0 if following fields are valid */
- unsigned long last_updated; /* In jiffies */
- u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH 12-bit samples */
+ struct mutex update_lock;
+ char valid;
+ unsigned long last_updated;
+ u16 adc_input[ADS7828_NCH];
+ unsigned int lsb_resol;
+ s32 (*read_channel)(const struct i2c_client *client, u8 command);
};
-/* Function declaration - necessary due to function dependencies */
-static int ads7828_detect(struct i2c_client *client,
- struct i2c_board_info *info);
-static int ads7828_probe(struct i2c_client *client,
- const struct i2c_device_id *id);
-
static inline u8 channel_cmd_byte(int ch)
{
/* cmd byte C2,C1,C0 - see datasheet */
@@ -97,8 +102,7 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
for (ch = 0; ch < ADS7828_NCH; ch++) {
u8 cmd = channel_cmd_byte(ch);
- data->adc_input[ch] =
- i2c_smbus_read_word_swapped(client, cmd);
+ data->adc_input[ch] = data->read_channel(client, cmd);
}
data->last_updated = jiffies;
data->valid = 1;
@@ -116,8 +120,8 @@ static ssize_t show_in(struct device *dev, struct device_attribute *da,
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ads7828_data *data = ads7828_update_device(dev);
/* Print value (in mV as specified in sysfs-interface documentation) */
- return sprintf(buf, "%d\n", (data->adc_input[attr->index] *
- ads7828_lsb_resol)/1000);
+ return sprintf(buf, "%d\n",
+ (data->adc_input[attr->index] * data->lsb_resol) / 1000);
}
#define in_reg(offset)\
@@ -158,31 +162,13 @@ static int ads7828_remove(struct i2c_client *client)
return 0;
}
-static const struct i2c_device_id ads7828_id[] = {
- { "ads7828", 0 },
- { }
-};
-MODULE_DEVICE_TABLE(i2c, ads7828_id);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver ads7828_driver = {
- .class = I2C_CLASS_HWMON,
- .driver = {
- .name = "ads7828",
- },
- .probe = ads7828_probe,
- .remove = ads7828_remove,
- .id_table = ads7828_id,
- .detect = ads7828_detect,
- .address_list = normal_i2c,
-};
-
/* Return 0 if detection is successful, -ENODEV otherwise */
static int ads7828_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
int ch;
+ bool is_8bit = false;
/* Check we have a valid client */
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA))
@@ -193,20 +179,30 @@ static int ads7828_detect(struct i2c_client *client,
* dedicated register so attempt to sanity check using knowledge of
* the chip
* - Read from the 8 channel addresses
- * - Check the top 4 bits of each result are not set (12 data bits)
+ * - Check the top 4 bits of each result:
+ * - They should not be set in case of 12-bit samples
+ * - The two bytes should be equal in case of 8-bit samples
*/
for (ch = 0; ch < ADS7828_NCH; ch++) {
u16 in_data;
u8 cmd = channel_cmd_byte(ch);
in_data = i2c_smbus_read_word_swapped(client, cmd);
if (in_data & 0xF000) {
- pr_debug("%s : Doesn't look like an ads7828 device\n",
- __func__);
- return -ENODEV;
+ if ((in_data >> 8) == (in_data & 0xFF)) {
+ /* Seems to be an ADS7830 (8-bit sample) */
+ is_8bit = true;
+ } else {
+ dev_dbg(&client->dev, "doesn't look like an "
+ "ADS7828 compatible device\n");
+ return -ENODEV;
+ }
}
}
- strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
+ if (is_8bit)
+ strlcpy(info->type, "ads7830", I2C_NAME_SIZE);
+ else
+ strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
return 0;
}
@@ -223,6 +219,15 @@ static int ads7828_probe(struct i2c_client *client,
goto exit;
}
+ /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
+ if (id->driver_data == ads7828) {
+ data->read_channel = i2c_smbus_read_word_swapped;
+ data->lsb_resol = (vref_mv * 1000) / 4096;
+ } else {
+ data->read_channel = i2c_smbus_read_byte_data;
+ data->lsb_resol = (vref_mv * 1000) / 256;
+ }
+
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
@@ -247,6 +252,25 @@ exit:
return err;
}
+static const struct i2c_device_id ads7828_ids[] = {
+ { "ads7828", ads7828 },
+ { "ads7830", ads7830 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ads7828_ids);
+
+static struct i2c_driver ads7828_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "ads7828",
+ },
+ .probe = ads7828_probe,
+ .remove = ads7828_remove,
+ .id_table = ads7828_ids,
+ .detect = ads7828_detect,
+ .address_list = normal_i2c,
+};
+
static int __init sensors_ads7828_init(void)
{
/* Initialize the command byte according to module parameters */
@@ -255,9 +279,6 @@ static int __init sensors_ads7828_init(void)
ads7828_cmd_byte |= int_vref ?
ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
- /* Calculate the LSB resolution */
- ads7828_lsb_resol = (vref_mv*1000)/4096;
-
return i2c_add_driver(&ads7828_driver);
}
@@ -267,7 +288,7 @@ static void __exit sensors_ads7828_exit(void)
}
MODULE_AUTHOR("Steve Hardy <sha...@redhat.com>");
-MODULE_DESCRIPTION("ADS7828 driver");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles");
MODULE_LICENSE("GPL");
module_init(sensors_ads7828_init);
--
1.7.11.4
--
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Please read the FAQ at http://www.tux.org/lkml/
Vivien Didelot
Oct 1, 2012, 5:20:02 PM10/1/12
to
Oops, I used the wrong address for Guenter. Here we go.
Thanks,
Vivien
----- Mail original -----
De: "Vivien Didelot" <vivien....@savoirfairelinux.com>
À: lm-se...@lm-sensors.org
Cc: "Guillaume Roguez" <guillaum...@savoirfairelinux.com>, "Guenter Roeck" <guente...@ericsson.com>, "Jean Delvare" <kh...@linux-fr.org>, linux-...@vger.kernel.org, "Steve Hardy" <sha...@redhat.com>, "Vivien Didelot" <vivien....@savoirfairelinux.com>
Envoyé: Lundi 1 Octobre 2012 16:44:20
Objet: [PATCH] hwmon: (ads7828) add support for ADS7830
Thanks,
Vivien
----- Mail original -----
De: "Vivien Didelot" <vivien....@savoirfairelinux.com>
À: lm-se...@lm-sensors.org
Cc: "Guillaume Roguez" <guillaum...@savoirfairelinux.com>, "Guenter Roeck" <guente...@ericsson.com>, "Jean Delvare" <kh...@linux-fr.org>, linux-...@vger.kernel.org, "Steve Hardy" <sha...@redhat.com>, "Vivien Didelot" <vivien....@savoirfairelinux.com>
Envoyé: Lundi 1 Octobre 2012 16:44:20
Objet: [PATCH] hwmon: (ads7828) add support for ADS7830
Guenter Roeck
Oct 1, 2012, 5:30:01 PM10/1/12
to
On Mon, Oct 01, 2012 at 05:09:11PM -0400, Vivien Didelot wrote:
> Oops, I used the wrong address for Guenter. Here we go.
>
Hi Vivien,
> Oops, I used the wrong address for Guenter. Here we go.
>
I got it anyway, through the mailing list...
> Thanks,
> Vivien
>
> ----- Mail original -----
> De: "Vivien Didelot" <vivien....@savoirfairelinux.com>
> Cc: "Guillaume Roguez" <guillaum...@savoirfairelinux.com>, "Guenter Roeck" <guente...@ericsson.com>, "Jean Delvare" <kh...@linux-fr.org>, linux-...@vger.kernel.org, "Steve Hardy" <sha...@redhat.com>, "Vivien Didelot" <vivien....@savoirfairelinux.com>
> Envoy�: Lundi 1 Octobre 2012 16:44:20
> Objet: [PATCH] hwmon: (ads7828) add support for ADS7830
>
> From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
>
> The ADS7830 is almost the same chip, except that it does 8-bit sampling.
> This patch extends the ads7828 driver to support this device.
>
> Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
>
> Also clean the driver a bit by removing unused macros, and moving
> the driver declaration to avoid some function prototypes.
>
One change per patch, please. Please handle the cleanup with a separate patch.
>
> From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
>
> The ADS7830 is almost the same chip, except that it does 8-bit sampling.
> This patch extends the ads7828 driver to support this device.
>
> Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
>
> Also clean the driver a bit by removing unused macros, and moving
> the driver declaration to avoid some function prototypes.
>
Other than that, not sure if the changes warrant a copyright, and you can not
add a copyright for a third person (or replace a "Written by" statement with a
copyright).
Thanks,
Guenter
Vivien Didelot
Oct 1, 2012, 5:40:01 PM10/1/12
to
On Mon, 2012-10-01 at 14:29 -0700, Guenter Roeck wrote:
> One change per patch, please. Please handle the cleanup with a
> separate patch.
>
> Other than that, not sure if the changes warrant a copyright, and you
> can not
> add a copyright for a third person (or replace a "Written by"
> statement with a
> copyright).
Hm ok, I wasn't sure about that. I'll send a fixup soon.
> One change per patch, please. Please handle the cleanup with a
> separate patch.
>
> Other than that, not sure if the changes warrant a copyright, and you
> can not
> add a copyright for a third person (or replace a "Written by"
> statement with a
> copyright).
Thank you,
Vivien
Vivien Didelot
Oct 1, 2012, 7:20:04 PM10/1/12
to
From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
The ADS7830 device is almost the same as the ADS7828,
except that it does 8-bit sampling, instead of 12-bit.
This patch extends the ads7828 driver to support this chip.
Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
Documentation/hwmon/ads7828 | 12 ++++++++--
drivers/hwmon/Kconfig | 7 +++---
drivers/hwmon/ads7828.c | 58 ++++++++++++++++++++++++++++++++-------------
3 files changed, 55 insertions(+), 22 deletions(-)
index fb3010d..91fc629 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -1,11 +1,13 @@
*
+ * ADS7830 support by Guillaume Roguez <guillaum...@savoirfairelinux.com>
+ *
@@ -53,9 +58,7 @@ module_param(se_input, bool, S_IRUGO);
module_param(int_vref, bool, S_IRUGO);
module_param(vref_mv, int, S_IRUGO);
-/* Global Variables */
* @valid: Validity flag.
char valid;
unsigned long last_updated;
for (ch = 0; ch < ADS7828_NCH; ch++) {
u8 cmd = channel_cmd_byte(ch);
- data->adc_input[ch] =
- i2c_smbus_read_word_swapped(client, cmd);
+ data->adc_input[ch] = data->read_channel(client, cmd);
}
data->last_updated = jiffies;
data->valid = 1;
@@ -115,8 +121,8 @@ static ssize_t show_in(struct device *dev, struct device_attribute *da,
@@ -202,6 +219,15 @@ static int ads7828_probe(struct i2c_client *client,
};
MODULE_DEVICE_TABLE(i2c, ads7828_ids);
@@ -250,9 +277,6 @@ static int __init sensors_ads7828_init(void)
ads7828_cmd_byte = se_input ? ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
-MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
The ADS7830 device is almost the same as the ADS7828,
except that it does 8-bit sampling, instead of 12-bit.
This patch extends the ads7828 driver to support this chip.
Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
Documentation/hwmon/ads7828 | 12 ++++++++--
drivers/hwmon/Kconfig | 7 +++---
drivers/hwmon/ads7828.c | 58 ++++++++++++++++++++++++++++++++-------------
3 files changed, 55 insertions(+), 22 deletions(-)
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -1,11 +1,13 @@
/*
- * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC
- * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC
+ * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles
* (C) 2007 EADS Astrium
*
* This driver is based on the lm75 and other lm_sensors/hwmon drivers
*
* Written by Steve Hardy <sha...@redhat.com>
*
+ * ADS7830 support by Guillaume Roguez <guillaum...@savoirfairelinux.com>
+ *
* For further information, see the Documentation/hwmon/ads7828 file.
*
* This program is free software; you can redistribute it and/or modify
@@ -41,6 +43,9 @@
*
* This program is free software; you can redistribute it and/or modify
#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A/D ON */
#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+/* List of supported devices */
+enum ads7828_chips { ads7828, ads7830 };
+
+enum ads7828_chips { ads7828, ads7830 };
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
I2C_CLIENT_END };
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
@@ -53,9 +58,7 @@ module_param(se_input, bool, S_IRUGO);
module_param(int_vref, bool, S_IRUGO);
module_param(vref_mv, int, S_IRUGO);
-/* Global Variables */
static u8 ads7828_cmd_byte; /* cmd byte without channel bits */
-static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
/**
-static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
* struct ads7828_data - client specific data
@@ -64,6 +67,8 @@ static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
* @valid: Validity flag.
* @last_updated: Last updated time (in jiffies).
* @adc_input: ADS7828_NCH samples.
+ * @lsb_resol: Resolution of the A/D converter sample LSB.
+ * @read_channel: Function used to read a channel.
+ * @lsb_resol: Resolution of the A/D converter sample LSB.
+ * @read_channel: Function used to read a channel.
*/
struct ads7828_data {
struct device *hwmon_dev;
@@ -71,6 +76,8 @@ struct ads7828_data {
struct ads7828_data {
struct device *hwmon_dev;
char valid;
unsigned long last_updated;
u16 adc_input[ADS7828_NCH];
+ unsigned int lsb_resol;
+ s32 (*read_channel)(const struct i2c_client *client, u8 command);
};
+ unsigned int lsb_resol;
+ s32 (*read_channel)(const struct i2c_client *client, u8 command);
};
static inline u8 channel_cmd_byte(int ch)
@@ -96,8 +103,7 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
for (ch = 0; ch < ADS7828_NCH; ch++) {
u8 cmd = channel_cmd_byte(ch);
- data->adc_input[ch] =
- i2c_smbus_read_word_swapped(client, cmd);
+ data->adc_input[ch] = data->read_channel(client, cmd);
}
data->last_updated = jiffies;
data->valid = 1;
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ads7828_data *data = ads7828_update_device(dev);
/* Print value (in mV as specified in sysfs-interface documentation) */
- return sprintf(buf, "%d\n", (data->adc_input[attr->index] *
- ads7828_lsb_resol)/1000);
+ return sprintf(buf, "%d\n",
+ (data->adc_input[attr->index] * data->lsb_resol) / 1000);
}
#define in_reg(offset) \
@@ -162,6 +168,7 @@ static int ads7828_detect(struct i2c_client *client,
struct ads7828_data *data = ads7828_update_device(dev);
/* Print value (in mV as specified in sysfs-interface documentation) */
- return sprintf(buf, "%d\n", (data->adc_input[attr->index] *
- ads7828_lsb_resol)/1000);
+ return sprintf(buf, "%d\n",
+ (data->adc_input[attr->index] * data->lsb_resol) / 1000);
}
#define in_reg(offset) \
{
struct i2c_adapter *adapter = client->adapter;
int ch;
+ bool is_8bit = false;
/* Check we have a valid client */
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA))
@@ -172,20 +179,30 @@ static int ads7828_detect(struct i2c_client *client,
struct i2c_adapter *adapter = client->adapter;
int ch;
+ bool is_8bit = false;
/* Check we have a valid client */
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA))
goto exit;
}
+ /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
+ if (id->driver_data == ads7828) {
+ data->read_channel = i2c_smbus_read_word_swapped;
+ data->lsb_resol = (vref_mv * 1000) / 4096;
+ } else {
+ data->read_channel = i2c_smbus_read_byte_data;
+ data->lsb_resol = (vref_mv * 1000) / 256;
+ }
+
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
@@ -227,7 +253,8 @@ exit:
}
+ /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
+ if (id->driver_data == ads7828) {
+ data->read_channel = i2c_smbus_read_word_swapped;
+ data->lsb_resol = (vref_mv * 1000) / 4096;
+ } else {
+ data->read_channel = i2c_smbus_read_byte_data;
+ data->lsb_resol = (vref_mv * 1000) / 256;
+ }
+
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
}
static const struct i2c_device_id ads7828_ids[] = {
static const struct i2c_device_id ads7828_ids[] = {
- { "ads7828", 0 },
+ { "ads7828", ads7828 },
+ { "ads7830", ads7830 },
{ }
+ { "ads7830", ads7830 },
};
MODULE_DEVICE_TABLE(i2c, ads7828_ids);
@@ -250,9 +277,6 @@ static int __init sensors_ads7828_init(void)
ads7828_cmd_byte = se_input ? ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
ads7828_cmd_byte |= int_vref ? ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
- /* Calculate the LSB resolution */
- ads7828_lsb_resol = (vref_mv*1000)/4096;
-
return i2c_add_driver(&ads7828_driver);
}
@@ -262,7 +286,7 @@ static void __exit sensors_ads7828_exit(void)
- /* Calculate the LSB resolution */
- ads7828_lsb_resol = (vref_mv*1000)/4096;
-
return i2c_add_driver(&ads7828_driver);
}
-MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles");
MODULE_LICENSE("GPL");
module_init(sensors_ads7828_init);
--
1.7.11.4
MODULE_LICENSE("GPL");
module_init(sensors_ads7828_init);
--
1.7.11.4
Vivien Didelot
Oct 1, 2012, 7:20:04 PM10/1/12
to
* Remove unused macros;
* Point to the documentation;
* Coding Style fixes (Kernel Doc, spacing);
* Move driver declaration to avoid adding function prototypes.
drivers/hwmon/ads7828.c | 91 +++++++++++++++++++++++--------------------------
1 file changed, 43 insertions(+), 48 deletions(-)
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index bf3fdf4..fb3010d 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -6,7 +6,7 @@
+#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
@@ -59,25 +57,26 @@ module_param(vref_mv, int, S_IRUGO);
+ * @adc_input: ADS7828_NCH samples.
+ */
+ u8 cmd = (((ch >> 1) | (ch & 0x01) << 2) << 4);
cmd |= ads7828_cmd_byte;
return cmd;
}
@@ -120,9 +119,8 @@ static ssize_t show_in(struct device *dev, struct device_attribute *da,
ads7828_lsb_resol)/1000);
}
-#define in_reg(offset)\
-static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in,\
- NULL, offset)
+#define in_reg(offset) \
+static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in, NULL, offset)
in_reg(0);
in_reg(1);
@@ -158,25 +156,6 @@ static int ads7828_remove(struct i2c_client *client)
return 0;
}
-static const struct i2c_device_id ads7828_id[] = {
@@ -247,13 +226,29 @@ exit:
return err;
}
+static const struct i2c_device_id ads7828_ids[] = {
+ { "ads7828", 0 },
+ { }
- ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
- ads7828_cmd_byte |= int_vref ?
- ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
+ ads7828_cmd_byte = se_input ? ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
+ ads7828_cmd_byte |= int_vref ? ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
/* Calculate the LSB resolution */
ads7828_lsb_resol = (vref_mv*1000)/4096;
@@ -267,7 +262,7 @@ static void __exit sensors_ads7828_exit(void)
-MODULE_DESCRIPTION("ADS7828 driver");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
* Point to the documentation;
* Coding Style fixes (Kernel Doc, spacing);
* Move driver declaration to avoid adding function prototypes.
drivers/hwmon/ads7828.c | 91 +++++++++++++++++++++++--------------------------
1 file changed, 43 insertions(+), 48 deletions(-)
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index bf3fdf4..fb3010d 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -6,7 +6,7 @@
- * Datasheet available at: http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * For further information, see the Documentation/hwmon/ads7828 file.
*
* This program is free software; you can redistribute it and/or modify
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -34,14 +34,12 @@
#include <linux/mutex.h>
/* The ADS7828 registers */
-#define ADS7828_NCH 8 /* 8 channels of 12-bit A-D supported */
-#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
-#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
-#define ADS7828_CMD_PD0 0x0 /* Power Down between A-D conversions */
-#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A-D ON */
-#define ADS7828_CMD_PD2 0x08 /* Internal ref ON && A-D OFF */
-#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A-D ON */
-#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+#define ADS7828_NCH 8 /* 8 channels supported */
+#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
+#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
+#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A/D ON */
+#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A/D ON */
/* The ADS7828 registers */
-#define ADS7828_NCH 8 /* 8 channels of 12-bit A-D supported */
-#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
-#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
-#define ADS7828_CMD_PD0 0x0 /* Power Down between A-D conversions */
-#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A-D ON */
-#define ADS7828_CMD_PD2 0x08 /* Internal ref ON && A-D OFF */
-#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A-D ON */
-#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+#define ADS7828_NCH 8 /* 8 channels supported */
+#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
+#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
+#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A/D ON */
+#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
static u8 ads7828_cmd_byte; /* cmd byte without channel bits */
static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
-/* Each client has this additional data */
+/**
+ * struct ads7828_data - client specific data
+ * @hwmon_dev: The hwmon device.
+ * @update_lock: Mutex protecting updates.
+ * @valid: Validity flag.
+ * @last_updated: Last updated time (in jiffies).
+/**
+ * struct ads7828_data - client specific data
+ * @hwmon_dev: The hwmon device.
+ * @update_lock: Mutex protecting updates.
+ * @valid: Validity flag.
+ * @adc_input: ADS7828_NCH samples.
+ */
struct ads7828_data {
struct device *hwmon_dev;
struct device *hwmon_dev;
- struct mutex update_lock; /* mutex protect updates */
- char valid; /* !=0 if following fields are valid */
- unsigned long last_updated; /* In jiffies */
- u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH 12-bit samples */
+ struct mutex update_lock;
+ char valid;
+ unsigned long last_updated;
+ u16 adc_input[ADS7828_NCH];
- char valid; /* !=0 if following fields are valid */
- unsigned long last_updated; /* In jiffies */
- u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH 12-bit samples */
+ struct mutex update_lock;
+ char valid;
+ unsigned long last_updated;
+ u16 adc_input[ADS7828_NCH];
};
-/* Function declaration - necessary due to function dependencies */
-static int ads7828_detect(struct i2c_client *client,
- struct i2c_board_info *info);
-static int ads7828_probe(struct i2c_client *client,
- const struct i2c_device_id *id);
-
-/* Function declaration - necessary due to function dependencies */
-static int ads7828_detect(struct i2c_client *client,
- struct i2c_board_info *info);
-static int ads7828_probe(struct i2c_client *client,
- const struct i2c_device_id *id);
-
static inline u8 channel_cmd_byte(int ch)
{
/* cmd byte C2,C1,C0 - see datasheet */
- u8 cmd = (((ch>>1) | (ch&0x01)<<2)<<4);
/* cmd byte C2,C1,C0 - see datasheet */
+ u8 cmd = (((ch >> 1) | (ch & 0x01) << 2) << 4);
cmd |= ads7828_cmd_byte;
return cmd;
}
@@ -120,9 +119,8 @@ static ssize_t show_in(struct device *dev, struct device_attribute *da,
ads7828_lsb_resol)/1000);
}
-#define in_reg(offset)\
-static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in,\
- NULL, offset)
+#define in_reg(offset) \
+static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in, NULL, offset)
in_reg(0);
in_reg(1);
@@ -158,25 +156,6 @@ static int ads7828_remove(struct i2c_client *client)
return 0;
}
-static const struct i2c_device_id ads7828_id[] = {
- { "ads7828", 0 },
- { }
-};
-MODULE_DEVICE_TABLE(i2c, ads7828_id);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver ads7828_driver = {
- .class = I2C_CLASS_HWMON,
- .driver = {
- .name = "ads7828",
- },
- .probe = ads7828_probe,
- .remove = ads7828_remove,
- .id_table = ads7828_id,
- .detect = ads7828_detect,
- .address_list = normal_i2c,
-};
-
/* Return 0 if detection is successful, -ENODEV otherwise */
-};
-MODULE_DEVICE_TABLE(i2c, ads7828_id);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver ads7828_driver = {
- .class = I2C_CLASS_HWMON,
- .driver = {
- .name = "ads7828",
- },
- .probe = ads7828_probe,
- .remove = ads7828_remove,
- .id_table = ads7828_id,
- .detect = ads7828_detect,
- .address_list = normal_i2c,
-};
-
/* Return 0 if detection is successful, -ENODEV otherwise */
static int ads7828_detect(struct i2c_client *client,
struct i2c_board_info *info)
@@ -247,13 +226,29 @@ exit:
return err;
}
+static const struct i2c_device_id ads7828_ids[] = {
+ { "ads7828", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ads7828_ids);
+
+static struct i2c_driver ads7828_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "ads7828",
+ },
+ .address_list = normal_i2c,
+MODULE_DEVICE_TABLE(i2c, ads7828_ids);
+
+static struct i2c_driver ads7828_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "ads7828",
+ },
+ .detect = ads7828_detect,
+ .probe = ads7828_probe,
+ .remove = ads7828_remove,
+ .id_table = ads7828_ids,
+ .probe = ads7828_probe,
+ .remove = ads7828_remove,
+ .id_table = ads7828_ids,
+};
+
static int __init sensors_ads7828_init(void)
{
/* Initialize the command byte according to module parameters */
- ads7828_cmd_byte = se_input ?
+
static int __init sensors_ads7828_init(void)
{
/* Initialize the command byte according to module parameters */
- ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
- ads7828_cmd_byte |= int_vref ?
- ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
+ ads7828_cmd_byte = se_input ? ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
+ ads7828_cmd_byte |= int_vref ? ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
/* Calculate the LSB resolution */
@@ -267,7 +262,7 @@ static void __exit sensors_ads7828_exit(void)
-MODULE_DESCRIPTION("ADS7828 driver");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
Guenter Roeck
Oct 1, 2012, 9:10:03 PM10/1/12
to
On Mon, Oct 01, 2012 at 07:16:23PM -0400, Vivien Didelot wrote:
> * Remove unused macros;
> * Point to the documentation;
> * Coding Style fixes (Kernel Doc, spacing);
> * Move driver declaration to avoid adding function prototypes.
>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Hi Vivien,
> * Remove unused macros;
> * Point to the documentation;
> * Coding Style fixes (Kernel Doc, spacing);
> * Move driver declaration to avoid adding function prototypes.
>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
document it this way. No strong opinion, just wondering.
> struct ads7828_data {
> struct device *hwmon_dev;
> - struct mutex update_lock; /* mutex protect updates */
> - char valid; /* !=0 if following fields are valid */
> - unsigned long last_updated; /* In jiffies */
> - u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH 12-bit samples */
> + struct mutex update_lock;
> + char valid;
> + unsigned long last_updated;
> + u16 adc_input[ADS7828_NCH];
> };
>
> -/* Function declaration - necessary due to function dependencies */
> -static int ads7828_detect(struct i2c_client *client,
> - struct i2c_board_info *info);
> -static int ads7828_probe(struct i2c_client *client,
> - const struct i2c_device_id *id);
> -
> static inline u8 channel_cmd_byte(int ch)
> {
> /* cmd byte C2,C1,C0 - see datasheet */
> - u8 cmd = (((ch>>1) | (ch&0x01)<<2)<<4);
> + u8 cmd = (((ch >> 1) | (ch & 0x01) << 2) << 4);
> cmd |= ads7828_cmd_byte;
> return cmd;
> }
> @@ -120,9 +119,8 @@ static ssize_t show_in(struct device *dev, struct device_attribute *da,
> ads7828_lsb_resol)/1000);
[ Wonder why checkpatch doesn't complain about it ]
> }
>
> -#define in_reg(offset)\
> -static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in,\
> - NULL, offset)
> +#define in_reg(offset) \
> +static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in, NULL, offset)
>
> in_reg(0);
> in_reg(1);
Since it seems to be hardly worth it anyway (yes, I know there are 8 of them),
would be great if you can just get rid of the macro and just use
static SENSOR_DEVICE_ATTR(in[1-8]_input, ...)
instead.
Guenter Roeck
Oct 1, 2012, 9:30:01 PM10/1/12
to
On Mon, Oct 01, 2012 at 07:16:24PM -0400, Vivien Didelot wrote:
> From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
>
> The ADS7830 device is almost the same as the ADS7828,
> except that it does 8-bit sampling, instead of 12-bit.
> This patch extends the ads7828 driver to support this chip.
>
> Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Hi Guillaume,
> From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
>
> The ADS7830 device is almost the same as the ADS7828,
> except that it does 8-bit sampling, instead of 12-bit.
> This patch extends the ads7828 driver to support this chip.
>
> Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Hi Vivien,
couple of comments below.
parameters doesn't seem to be right here. Should be platform data or device
tree. But that is for later ... just something to keep in mind.
in_data should be defined as int, and you should check for an error and
abort if there is one (previously that was covered in the "& 0xF000", but that
is no longer the case).
> if (in_data & 0xF000) {
> - pr_debug("%s : Doesn't look like an ads7828 device\n",
> - __func__);
> - return -ENODEV;
> + if ((in_data >> 8) == (in_data & 0xFF)) {
> + /* Seems to be an ADS7830 (8-bit sample) */
> + is_8bit = true;
> + } else {
> + dev_dbg(&client->dev, "doesn't look like an "
> + "ADS7828 compatible device\n");
#190: FILE: drivers/hwmon/ads7828.c:196:
+ dev_dbg(&client->dev, "doesn't look like an "
+ "ADS7828 compatible device\n");
Better:
+ "ADS7828 compatible device\n");
dev_dbg(&client->dev,
"doesn't look like an ADS7828 compatible device\n");
> + return -ENODEV;
> + }
> }
> }
>
> - strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
> + if (is_8bit)
> + strlcpy(info->type, "ads7830", I2C_NAME_SIZE);
> + else
> + strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
>
> return 0;
> }
> @@ -202,6 +219,15 @@ static int ads7828_probe(struct i2c_client *client,
> goto exit;
> }
>
> + /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
> + if (id->driver_data == ads7828) {
> + data->read_channel = i2c_smbus_read_word_swapped;
> + data->lsb_resol = (vref_mv * 1000) / 4096;
> + } else {
> + data->read_channel = i2c_smbus_read_byte_data;
> + data->lsb_resol = (vref_mv * 1000) / 256;
Would DIV_ROUND_CLOSEST be better ?
Vivien Didelot
Oct 1, 2012, 10:30:01 PM10/1/12
to
Hi Guenter,
I found the version below a bit cluttered, that's why I used the
KernelDoc notation. Would you prefer something else, like right-aligned
comments?
Sure.
checkpatch.pl too.
Thanks for your comments,
Vivien
KernelDoc notation. Would you prefer something else, like right-aligned
comments?
>
> > }
> >
> > -#define in_reg(offset)\
> > -static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in,\
> > - NULL, offset)
> > +#define in_reg(offset) \
> > +static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in, NULL, offset)
> >
> This causes a checkpatch error - checkpatch doesn't like the multi-line macros.
My bad, I'm on a 2.6.37 box, I didn't checkout the upstream version of
> > }
> >
> > -#define in_reg(offset)\
> > -static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in,\
> > - NULL, offset)
> > +#define in_reg(offset) \
> > +static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in, NULL, offset)
> >
> This causes a checkpatch error - checkpatch doesn't like the multi-line macros.
checkpatch.pl too.
>
> > in_reg(0);
> > in_reg(1);
>
> Since it seems to be hardly worth it anyway (yes, I know there are 8 of them),
> would be great if you can just get rid of the macro and just use
> static SENSOR_DEVICE_ATTR(in[1-8]_input, ...)
> instead.
Ok.
> > in_reg(0);
> > in_reg(1);
>
> Since it seems to be hardly worth it anyway (yes, I know there are 8 of them),
> would be great if you can just get rid of the macro and just use
> static SENSOR_DEVICE_ATTR(in[1-8]_input, ...)
> instead.
Vivien
Guenter Roeck
Oct 1, 2012, 11:00:01 PM10/1/12
to
On Mon, Oct 01, 2012 at 10:16:07PM -0400, Vivien Didelot wrote:
> Hi Guenter,
>
[ ... ]
Guenter
> Hi Guenter,
>
[ ... ]
> > >
> > > -/* Each client has this additional data */
> > > +/**
> > > + * struct ads7828_data - client specific data
> > > + * @hwmon_dev: The hwmon device.
> > > + * @update_lock: Mutex protecting updates.
> > > + * @valid: Validity flag.
> > > + * @last_updated: Last updated time (in jiffies).
> > > + * @adc_input: ADS7828_NCH samples.
> > > + */
> > This isn't really an externally visible API, so I wonder if it provides value to
> > document it this way. No strong opinion, just wondering.
> I found the version below a bit cluttered, that's why I used the
> KernelDoc notation. Would you prefer something else, like right-aligned
> comments?
Tab aligned, maybe ? Not sure if that works out, though.
> > > -/* Each client has this additional data */
> > > +/**
> > > + * struct ads7828_data - client specific data
> > > + * @hwmon_dev: The hwmon device.
> > > + * @update_lock: Mutex protecting updates.
> > > + * @valid: Validity flag.
> > > + * @last_updated: Last updated time (in jiffies).
> > > + * @adc_input: ADS7828_NCH samples.
> > > + */
> > This isn't really an externally visible API, so I wonder if it provides value to
> > document it this way. No strong opinion, just wondering.
> I found the version below a bit cluttered, that's why I used the
> KernelDoc notation. Would you prefer something else, like right-aligned
> comments?
Guenter
Vivien Didelot
Oct 1, 2012, 11:30:02 PM10/1/12
to
Hi Guenter,
Sounds like an abuse of the serial comma :-)
Good catch.
string... Makes sense.
DIV_ROUND_CLOSEST.
Thanks,
Vivien
>
> > if (in_data & 0xF000) {
> > - pr_debug("%s : Doesn't look like an ads7828 device\n",
> > - __func__);
> > - return -ENODEV;
> > + if ((in_data >> 8) == (in_data & 0xFF)) {
> > + /* Seems to be an ADS7830 (8-bit sample) */
> > + is_8bit = true;
> > + } else {
> > + dev_dbg(&client->dev, "doesn't look like an "
> > + "ADS7828 compatible device\n");
>
> WARNING: quoted string split across lines
> #190: FILE: drivers/hwmon/ads7828.c:196:
> + dev_dbg(&client->dev, "doesn't look like an "
> + "ADS7828 compatible device\n");
Hum ok, so the reason for that is that it breaks the ability to grep a
> > if (in_data & 0xF000) {
> > - pr_debug("%s : Doesn't look like an ads7828 device\n",
> > - __func__);
> > - return -ENODEV;
> > + if ((in_data >> 8) == (in_data & 0xFF)) {
> > + /* Seems to be an ADS7830 (8-bit sample) */
> > + is_8bit = true;
> > + } else {
> > + dev_dbg(&client->dev, "doesn't look like an "
> > + "ADS7828 compatible device\n");
>
> WARNING: quoted string split across lines
> #190: FILE: drivers/hwmon/ads7828.c:196:
> + dev_dbg(&client->dev, "doesn't look like an "
> + "ADS7828 compatible device\n");
string... Makes sense.
>
> Better:
> dev_dbg(&client->dev,
> "doesn't look like an ADS7828 compatible device\n");
This exceeds 80 chars, but I'll find a shorter message.
> Better:
> dev_dbg(&client->dev,
> "doesn't look like an ADS7828 compatible device\n");
>
> > + return -ENODEV;
> > + }
> > }
> > }
> >
> > - strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
> > + if (is_8bit)
> > + strlcpy(info->type, "ads7830", I2C_NAME_SIZE);
> > + else
> > + strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
> >
> > return 0;
> > }
> > @@ -202,6 +219,15 @@ static int ads7828_probe(struct i2c_client *client,
> > goto exit;
> > }
> >
> > + /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
> > + if (id->driver_data == ads7828) {
> > + data->read_channel = i2c_smbus_read_word_swapped;
> > + data->lsb_resol = (vref_mv * 1000) / 4096;
> > + } else {
> > + data->read_channel = i2c_smbus_read_byte_data;
> > + data->lsb_resol = (vref_mv * 1000) / 256;
>
> Just wondering ... does that introduce a rounding error ?
> Would DIV_ROUND_CLOSEST be better ?
Since it is still a module parameter, yes, it will be safer to use
> > + return -ENODEV;
> > + }
> > }
> > }
> >
> > - strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
> > + if (is_8bit)
> > + strlcpy(info->type, "ads7830", I2C_NAME_SIZE);
> > + else
> > + strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
> >
> > return 0;
> > }
> > @@ -202,6 +219,15 @@ static int ads7828_probe(struct i2c_client *client,
> > goto exit;
> > }
> >
> > + /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
> > + if (id->driver_data == ads7828) {
> > + data->read_channel = i2c_smbus_read_word_swapped;
> > + data->lsb_resol = (vref_mv * 1000) / 4096;
> > + } else {
> > + data->read_channel = i2c_smbus_read_byte_data;
> > + data->lsb_resol = (vref_mv * 1000) / 256;
>
> Just wondering ... does that introduce a rounding error ?
> Would DIV_ROUND_CLOSEST be better ?
DIV_ROUND_CLOSEST.
Vivien
Guenter Roeck
Oct 2, 2012, 12:40:01 AM10/2/12
to
On Mon, Oct 01, 2012 at 11:28:21PM -0400, Vivien Didelot wrote:
> Hi Guenter,
>
Hi Vivien,
> Hi Guenter,
>
[ ... ]
> > > + } else {
> > > + dev_dbg(&client->dev, "doesn't look like an "
> > > + "ADS7828 compatible device\n");
> >
> > WARNING: quoted string split across lines
> > #190: FILE: drivers/hwmon/ads7828.c:196:
> > + dev_dbg(&client->dev, "doesn't look like an "
> > + "ADS7828 compatible device\n");
> Hum ok, so the reason for that is that it breaks the ability to grep a
> string... Makes sense.
> >
> > Better:
> > dev_dbg(&client->dev,
> > "doesn't look like an ADS7828 compatible device\n");
> This exceeds 80 chars, but I'll find a shorter message.
Guenter
Vivien Didelot
Oct 2, 2012, 6:20:02 PM10/2/12
to
* Remove module parameters, add a ads7828_platform_data;
* Move driver declaration to avoid adding function prototypes;
* Remove unused macros;
* Coding Style fixes.
Documentation/hwmon/ads7828 | 31 +++--
drivers/hwmon/ads7828.c | 216 +++++++++++++++++-----------------
include/linux/platform_data/ads7828.h | 29 +++++
3 files changed, 155 insertions(+), 121 deletions(-)
create mode 100644 include/linux/platform_data/ads7828.h
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828
index 2bbebe6..b35668c 100644
--- a/Documentation/hwmon/ads7828
+++ b/Documentation/hwmon/ads7828
@@ -5,21 +5,32 @@ Supported chips:
* Texas Instruments/Burr-Brown ADS7828
Prefix: 'ads7828'
+ Datasheet: Publicly available at the Texas Instruments website:
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
Authors:
Steve Hardy <sha...@redhat.com>
-Module Parameters
------------------
-
-* se_input: bool (default Y)
- Single ended operation - set to N for differential mode
-* int_vref: bool (default Y)
- Operate with the internal 2.5V reference - set to N for external reference
-* vref_mv: int (default 2500)
- If using an external reference, set this to the reference voltage in mV
+Platform data
+-------------
+
+The ads7828 driver accepts an optional ads7828_platform_data structure (defined
+in include/linux/platform_data/ads7828.h). If no structure is provided, the
+configuration defaults to single ended operation and internal vref (2.5V).
+
+The structure fields are:
+
+* diff_input: bool
+ Differential operation - set to true for differential mode,
+ false for default single ended mode.
+* ext_vref: bool
+ External reference - set to true if it operates with an external reference,
+ false for default internal reference.
+* vref_mv: int
+ Voltage reference - if using an external reference, set this to the reference
+ voltage in mV, otherwise, it will default to the internal value (2500mV).
+ This value will be bounded with limits accepted by the chip, described in the
+ datasheet.
Description
-----------
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index bf3fdf4..0a13bf8 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -6,7 +6,7 @@
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/slab.h>
-#include <linux/jiffies.h>
-#include <linux/i2c.h>
+#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
-#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/platform_data/ads7828.h>
+#include <linux/slab.h>
/* The ADS7828 registers */
-#define ADS7828_NCH 8 /* 8 channels of 12-bit A-D supported */
-#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
-#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
-#define ADS7828_CMD_PD0 0x0 /* Power Down between A-D conversions */
-#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A-D ON */
-#define ADS7828_CMD_PD2 0x08 /* Internal ref ON && A-D OFF */
-#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A-D ON */
-#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+#define ADS7828_NCH 8 /* 8 channels supported */
+#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
+#define ADS7828_CMD_PD1 0x04 /* Internal vref OFF && A/D ON */
+#define ADS7828_CMD_PD3 0x0C /* Internal vref ON && A/D ON */
+#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+#define ADS7828_EXT_VREF_MV_MIN 50 /* External vref min value 0.05V */
+#define ADS7828_EXT_VREF_MV_MAX 5250 /* External vref max value 5.25V */
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
I2C_CLIENT_END };
-/* Module parameters */
-static bool se_input = 1; /* Default is SE, 0 == diff */
-static bool int_vref = 1; /* Default is internal ref ON */
-static int vref_mv = ADS7828_INT_VREF_MV; /* set if vref != 2.5V */
-module_param(se_input, bool, S_IRUGO);
-module_param(int_vref, bool, S_IRUGO);
-module_param(vref_mv, int, S_IRUGO);
-
-/* Global Variables */
-static u8 ads7828_cmd_byte; /* cmd byte without channel bits */
+ unsigned long last_updated; /* Last updated time (in jiffies) */
+ u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH samples */
+ bool valid; /* Validity flag */
+ bool diff_input; /* Differential input */
+ bool ext_vref; /* External voltage reference */
+ unsigned int vref_mv; /* voltage reference value */
+ u8 cmd_byte; /* Command byte without channel bits */
+ unsigned int lsb_resol; /* Resolution of the ADC sample LSB */
+/* Command byte C2,C1,C0 - see datasheet */
+static inline u8 ads7828_cmd_byte(u8 cmd, int ch)
{
- /* cmd byte C2,C1,C0 - see datasheet */
- return cmd;
+ return cmd | (((ch >> 1) | (ch & 0x01) << 2) << 4);
}
/* Update data for the device (all 8 channels) */
@@ -96,12 +81,12 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
dev_dbg(&client->dev, "Starting ads7828 update\n");
for (ch = 0; ch < ADS7828_NCH; ch++) {
- u8 cmd = channel_cmd_byte(ch);
+ u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch);
data->adc_input[ch] =
i2c_smbus_read_word_swapped(client, cmd);
}
data->last_updated = jiffies;
- data->valid = 1;
+ data->valid = true;
}
mutex_unlock(&data->update_lock);
@@ -110,28 +95,25 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
}
/* sysfs callback function */
-static ssize_t show_in(struct device *dev, struct device_attribute *da,
- char *buf)
+static ssize_t ads7828_show_in(struct device *dev, struct device_attribute *da,
+ char *buf)
{
+ unsigned int value = DIV_ROUND_CLOSEST(data->adc_input[attr->index] *
+ data->lsb_resol, 1000);
-#define in_reg(offset)\
-static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in,\
- NULL, offset)
+ return sprintf(buf, "%d\n", value);
+}
-in_reg(0);
-in_reg(1);
-in_reg(2);
-in_reg(3);
-in_reg(4);
-in_reg(5);
-in_reg(6);
-in_reg(7);
+static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ads7828_show_in, NULL, 0);
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ads7828_show_in, NULL, 1);
+static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ads7828_show_in, NULL, 2);
+static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ads7828_show_in, NULL, 3);
+static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ads7828_show_in, NULL, 4);
+static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, ads7828_show_in, NULL, 5);
+static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, ads7828_show_in, NULL, 6);
+static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, ads7828_show_in, NULL, 7);
static struct attribute *ads7828_attributes[] = {
&sensor_dev_attr_in0_input.dev_attr.attr,
@@ -152,36 +134,20 @@ static const struct attribute_group ads7828_group = {
struct ads7828_data *data = i2c_get_clientdata(client);
+
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
- kfree(i2c_get_clientdata(client));
+ i2c_set_clientdata(client, NULL);
+
return 0;
}
-static const struct i2c_device_id ads7828_id[] = {
int ch;
/* Check we have a valid client */
@@ -196,9 +162,12 @@ static int ads7828_detect(struct i2c_client *client,
- u8 cmd = channel_cmd_byte(ch);
- in_data = i2c_smbus_read_word_swapped(client, cmd);
+ u8 cmd = ads7828_cmd_byte(default_cmd_byte, ch);
+ u16 in_data = i2c_smbus_read_word_swapped(client, cmd);
+
+ if (in_data < 0)
+ return -ENODEV;
+
if (in_data & 0xF000) {
@@ -214,61 +183,86 @@ static int ads7828_detect(struct i2c_client *client,
{
- struct ads7828_data *data;
int err;
-
- data = kzalloc(sizeof(struct ads7828_data), GFP_KERNEL);
- if (!data) {
- err = -ENOMEM;
- goto exit;
+ struct ads7828_data *data;
+ struct ads7828_platform_data *pdata = client->dev.platform_data;
+
+ data = devm_kzalloc(&client->dev, sizeof(struct ads7828_data),
+ GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ if (pdata) {
+ data->diff_input = pdata->diff_input;
+ data->ext_vref = pdata->ext_vref;
+ if (data->ext_vref)
+ data->vref_mv = pdata->vref_mv;
}
+ /* Bound Vref with min/max values if it was provided */
+ if (data->vref_mv)
+ data->vref_mv = SENSORS_LIMIT(data->vref_mv,
+ ADS7828_EXT_VREF_MV_MIN,
+ ADS7828_EXT_VREF_MV_MAX);
+ else
+ data->vref_mv = ADS7828_INT_VREF_MV;
+
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+
+ data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
+ if (!data->diff_input)
+ data->cmd_byte |= ADS7828_CMD_SD_SE;
err = sysfs_create_group(&client->dev.kobj, &ads7828_group);
if (err)
- goto exit_free;
+ return err;
data->hwmon_dev = hwmon_device_register(&client->dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
- goto exit_remove;
+ goto error;
}
return 0;
-exit_remove:
+error:
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
-exit_free:
- kfree(data);
-exit:
return err;
}
-static int __init sensors_ads7828_init(void)
-{
- /* Initialize the command byte according to module parameters */
+ { "ads7828", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ads7828_ids);
- /* Calculate the LSB resolution */
- ads7828_lsb_resol = (vref_mv*1000)/4096;
return i2c_add_driver(&ads7828_driver);
}
+module_init(sensors_ads7828_init);
static void __exit sensors_ads7828_exit(void)
{
i2c_del_driver(&ads7828_driver);
}
+module_exit(sensors_ads7828_exit);
-MODULE_DESCRIPTION("ADS7828 driver");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
MODULE_LICENSE("GPL");
-
-module_init(sensors_ads7828_init);
-module_exit(sensors_ads7828_exit);
diff --git a/include/linux/platform_data/ads7828.h b/include/linux/platform_data/ads7828.h
new file mode 100644
index 0000000..3245f45
--- /dev/null
+++ b/include/linux/platform_data/ads7828.h
@@ -0,0 +1,29 @@
+/*
+ * TI ADS7828 A/D Converter platform data definition
+ *
+ * Copyright (c) 2012 Savoir-faire Linux Inc.
+ * Vivien Didelot <vivien....@savoirfairelinux.com>
+ *
+ * For further information, see the Documentation/hwmon/ads7828 file.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _PDATA_ADS7828_H
+#define _PDATA_ADS7828_H
+
+/**
+ * struct ads7828_platform_data - optional ADS7828 connectivity info
+ * @diff_input: Differential input mode.
+ * @ext_vref: Use an external voltage reference.
+ * @vref_mv: Voltage reference value, if external.
+ */
+struct ads7828_platform_data {
+ bool diff_input;
+ bool ext_vref;
+ unsigned int vref_mv;
+};
+
+#endif /* _PDATA_ADS7828_H */
--
1.7.11.4
* Move driver declaration to avoid adding function prototypes;
* Remove unused macros;
* Coding Style fixes.
Documentation/hwmon/ads7828 | 31 +++--
drivers/hwmon/ads7828.c | 216 +++++++++++++++++-----------------
include/linux/platform_data/ads7828.h | 29 +++++
3 files changed, 155 insertions(+), 121 deletions(-)
create mode 100644 include/linux/platform_data/ads7828.h
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828
index 2bbebe6..b35668c 100644
--- a/Documentation/hwmon/ads7828
+++ b/Documentation/hwmon/ads7828
@@ -5,21 +5,32 @@ Supported chips:
* Texas Instruments/Burr-Brown ADS7828
Prefix: 'ads7828'
Addresses scanned: I2C 0x48, 0x49, 0x4a, 0x4b
- Datasheet: Publicly available at the Texas Instruments website :
+ Datasheet: Publicly available at the Texas Instruments website:
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
Authors:
Steve Hardy <sha...@redhat.com>
-Module Parameters
------------------
-
-* se_input: bool (default Y)
- Single ended operation - set to N for differential mode
-* int_vref: bool (default Y)
- Operate with the internal 2.5V reference - set to N for external reference
-* vref_mv: int (default 2500)
- If using an external reference, set this to the reference voltage in mV
+Platform data
+-------------
+
+The ads7828 driver accepts an optional ads7828_platform_data structure (defined
+in include/linux/platform_data/ads7828.h). If no structure is provided, the
+configuration defaults to single ended operation and internal vref (2.5V).
+
+The structure fields are:
+
+* diff_input: bool
+ Differential operation - set to true for differential mode,
+ false for default single ended mode.
+* ext_vref: bool
+ External reference - set to true if it operates with an external reference,
+ false for default internal reference.
+* vref_mv: int
+ Voltage reference - if using an external reference, set this to the reference
+ voltage in mV, otherwise, it will default to the internal value (2500mV).
+ This value will be bounded with limits accepted by the chip, described in the
+ datasheet.
Description
-----------
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index bf3fdf4..0a13bf8 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -6,7 +6,7 @@
- * Datasheet available at: http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * For further information, see the Documentation/hwmon/ads7828 file.
*
* This program is free software; you can redistribute it and/or modify
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -23,63 +23,48 @@
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/slab.h>
-#include <linux/jiffies.h>
-#include <linux/i2c.h>
+#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
-#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/platform_data/ads7828.h>
+#include <linux/slab.h>
/* The ADS7828 registers */
-#define ADS7828_NCH 8 /* 8 channels of 12-bit A-D supported */
-#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
-#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
-#define ADS7828_CMD_PD0 0x0 /* Power Down between A-D conversions */
-#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A-D ON */
-#define ADS7828_CMD_PD2 0x08 /* Internal ref ON && A-D OFF */
-#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A-D ON */
-#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+#define ADS7828_NCH 8 /* 8 channels supported */
+#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
+#define ADS7828_CMD_PD3 0x0C /* Internal vref ON && A/D ON */
+#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+#define ADS7828_EXT_VREF_MV_MIN 50 /* External vref min value 0.05V */
+#define ADS7828_EXT_VREF_MV_MAX 5250 /* External vref max value 5.25V */
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
I2C_CLIENT_END };
-static bool se_input = 1; /* Default is SE, 0 == diff */
-static bool int_vref = 1; /* Default is internal ref ON */
-static int vref_mv = ADS7828_INT_VREF_MV; /* set if vref != 2.5V */
-module_param(se_input, bool, S_IRUGO);
-module_param(int_vref, bool, S_IRUGO);
-module_param(vref_mv, int, S_IRUGO);
-
-/* Global Variables */
-static u8 ads7828_cmd_byte; /* cmd byte without channel bits */
-static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
-
-/* Each client has this additional data */
+/* Client specific data */
struct ads7828_data {
struct device *hwmon_dev;
struct device *hwmon_dev;
- struct mutex update_lock; /* mutex protect updates */
- char valid; /* !=0 if following fields are valid */
- unsigned long last_updated; /* In jiffies */
- u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH 12-bit samples */
+ struct mutex update_lock; /* Mutex protecting updates */
- char valid; /* !=0 if following fields are valid */
- unsigned long last_updated; /* In jiffies */
- u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH 12-bit samples */
+ unsigned long last_updated; /* Last updated time (in jiffies) */
+ u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH samples */
+ bool valid; /* Validity flag */
+ bool diff_input; /* Differential input */
+ bool ext_vref; /* External voltage reference */
+ unsigned int vref_mv; /* voltage reference value */
+ u8 cmd_byte; /* Command byte without channel bits */
+ unsigned int lsb_resol; /* Resolution of the ADC sample LSB */
};
-/* Function declaration - necessary due to function dependencies */
-static int ads7828_detect(struct i2c_client *client,
- struct i2c_board_info *info);
-static int ads7828_probe(struct i2c_client *client,
- const struct i2c_device_id *id);
-
-static inline u8 channel_cmd_byte(int ch)
-/* Function declaration - necessary due to function dependencies */
-static int ads7828_detect(struct i2c_client *client,
- struct i2c_board_info *info);
-static int ads7828_probe(struct i2c_client *client,
- const struct i2c_device_id *id);
-
+/* Command byte C2,C1,C0 - see datasheet */
+static inline u8 ads7828_cmd_byte(u8 cmd, int ch)
{
- /* cmd byte C2,C1,C0 - see datasheet */
- u8 cmd = (((ch>>1) | (ch&0x01)<<2)<<4);
- cmd |= ads7828_cmd_byte;
- return cmd;
+ return cmd | (((ch >> 1) | (ch & 0x01) << 2) << 4);
}
/* Update data for the device (all 8 channels) */
@@ -96,12 +81,12 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
dev_dbg(&client->dev, "Starting ads7828 update\n");
for (ch = 0; ch < ADS7828_NCH; ch++) {
+ u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch);
data->adc_input[ch] =
i2c_smbus_read_word_swapped(client, cmd);
}
data->last_updated = jiffies;
- data->valid = 1;
+ data->valid = true;
}
mutex_unlock(&data->update_lock);
@@ -110,28 +95,25 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
}
/* sysfs callback function */
-static ssize_t show_in(struct device *dev, struct device_attribute *da,
- char *buf)
+static ssize_t ads7828_show_in(struct device *dev, struct device_attribute *da,
+ char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ads7828_data *data = ads7828_update_device(dev);
- /* Print value (in mV as specified in sysfs-interface documentation) */
struct ads7828_data *data = ads7828_update_device(dev);
- return sprintf(buf, "%d\n", (data->adc_input[attr->index] *
- ads7828_lsb_resol)/1000);
-}
- ads7828_lsb_resol)/1000);
+ unsigned int value = DIV_ROUND_CLOSEST(data->adc_input[attr->index] *
+ data->lsb_resol, 1000);
-#define in_reg(offset)\
-static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in,\
- NULL, offset)
+}
-in_reg(0);
-in_reg(1);
-in_reg(2);
-in_reg(3);
-in_reg(4);
-in_reg(5);
-in_reg(6);
-in_reg(7);
+static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ads7828_show_in, NULL, 0);
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ads7828_show_in, NULL, 1);
+static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ads7828_show_in, NULL, 2);
+static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ads7828_show_in, NULL, 3);
+static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ads7828_show_in, NULL, 4);
+static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, ads7828_show_in, NULL, 5);
+static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, ads7828_show_in, NULL, 6);
+static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, ads7828_show_in, NULL, 7);
static struct attribute *ads7828_attributes[] = {
&sensor_dev_attr_in0_input.dev_attr.attr,
@@ -152,36 +134,20 @@ static const struct attribute_group ads7828_group = {
static int ads7828_remove(struct i2c_client *client)
{
struct ads7828_data *data = i2c_get_clientdata(client);
+
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
- kfree(i2c_get_clientdata(client));
+ i2c_set_clientdata(client, NULL);
+
return 0;
}
-static const struct i2c_device_id ads7828_id[] = {
- { "ads7828", 0 },
- { }
-};
-MODULE_DEVICE_TABLE(i2c, ads7828_id);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver ads7828_driver = {
- .class = I2C_CLASS_HWMON,
- .driver = {
- .name = "ads7828",
- },
- .probe = ads7828_probe,
- .remove = ads7828_remove,
- .id_table = ads7828_id,
- .detect = ads7828_detect,
- .address_list = normal_i2c,
-};
-
/* Return 0 if detection is successful, -ENODEV otherwise */
-};
-MODULE_DEVICE_TABLE(i2c, ads7828_id);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver ads7828_driver = {
- .class = I2C_CLASS_HWMON,
- .driver = {
- .name = "ads7828",
- },
- .probe = ads7828_probe,
- .remove = ads7828_remove,
- .id_table = ads7828_id,
- .detect = ads7828_detect,
- .address_list = normal_i2c,
-};
-
/* Return 0 if detection is successful, -ENODEV otherwise */
static int ads7828_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
+ u8 default_cmd_byte = ADS7828_CMD_SD_SE | ADS7828_CMD_PD3;
struct i2c_adapter *adapter = client->adapter;
int ch;
/* Check we have a valid client */
* - Check the top 4 bits of each result are not set (12 data bits)
*/
for (ch = 0; ch < ADS7828_NCH; ch++) {
- u16 in_data;
for (ch = 0; ch < ADS7828_NCH; ch++) {
- u8 cmd = channel_cmd_byte(ch);
- in_data = i2c_smbus_read_word_swapped(client, cmd);
+ u8 cmd = ads7828_cmd_byte(default_cmd_byte, ch);
+ u16 in_data = i2c_smbus_read_word_swapped(client, cmd);
+
+ if (in_data < 0)
+ return -ENODEV;
+
if (in_data & 0xF000) {
pr_debug("%s : Doesn't look like an ads7828 device\n",
__func__);
@@ -214,61 +183,86 @@ static int ads7828_detect(struct i2c_client *client,
static int ads7828_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
- struct ads7828_data *data;
int err;
-
- data = kzalloc(sizeof(struct ads7828_data), GFP_KERNEL);
- if (!data) {
- err = -ENOMEM;
- goto exit;
+ struct ads7828_data *data;
+ struct ads7828_platform_data *pdata = client->dev.platform_data;
+
+ data = devm_kzalloc(&client->dev, sizeof(struct ads7828_data),
+ GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ if (pdata) {
+ data->diff_input = pdata->diff_input;
+ data->ext_vref = pdata->ext_vref;
+ if (data->ext_vref)
+ data->vref_mv = pdata->vref_mv;
}
+ /* Bound Vref with min/max values if it was provided */
+ if (data->vref_mv)
+ data->vref_mv = SENSORS_LIMIT(data->vref_mv,
+ ADS7828_EXT_VREF_MV_MIN,
+ ADS7828_EXT_VREF_MV_MAX);
+ else
+ data->vref_mv = ADS7828_INT_VREF_MV;
+
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+
+ data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
+ if (!data->diff_input)
+ data->cmd_byte |= ADS7828_CMD_SD_SE;
+
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
- /* Register sysfs hooks */
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
err = sysfs_create_group(&client->dev.kobj, &ads7828_group);
if (err)
- goto exit_free;
+ return err;
data->hwmon_dev = hwmon_device_register(&client->dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
- goto exit_remove;
+ goto error;
}
return 0;
-exit_remove:
+error:
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
-exit_free:
- kfree(data);
-exit:
return err;
}
-static int __init sensors_ads7828_init(void)
-{
- /* Initialize the command byte according to module parameters */
- ads7828_cmd_byte = se_input ?
- ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
- ads7828_cmd_byte |= int_vref ?
- ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
+static const struct i2c_device_id ads7828_ids[] = {
- ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
- ads7828_cmd_byte |= int_vref ?
- ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
+ { "ads7828", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ads7828_ids);
- /* Calculate the LSB resolution */
- ads7828_lsb_resol = (vref_mv*1000)/4096;
+static struct i2c_driver ads7828_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "ads7828",
+ },
+ .address_list = normal_i2c,
+ .detect = ads7828_detect,
+ .probe = ads7828_probe,
+ .remove = ads7828_remove,
+ .id_table = ads7828_ids,
+};
+static int __init sensors_ads7828_init(void)
+{
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "ads7828",
+ },
+ .address_list = normal_i2c,
+ .detect = ads7828_detect,
+ .probe = ads7828_probe,
+ .remove = ads7828_remove,
+ .id_table = ads7828_ids,
+};
+static int __init sensors_ads7828_init(void)
return i2c_add_driver(&ads7828_driver);
}
+module_init(sensors_ads7828_init);
static void __exit sensors_ads7828_exit(void)
{
i2c_del_driver(&ads7828_driver);
}
+module_exit(sensors_ads7828_exit);
-MODULE_DESCRIPTION("ADS7828 driver");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
MODULE_LICENSE("GPL");
-
-module_init(sensors_ads7828_init);
-module_exit(sensors_ads7828_exit);
diff --git a/include/linux/platform_data/ads7828.h b/include/linux/platform_data/ads7828.h
new file mode 100644
index 0000000..3245f45
--- /dev/null
+++ b/include/linux/platform_data/ads7828.h
@@ -0,0 +1,29 @@
+/*
+ * TI ADS7828 A/D Converter platform data definition
+ *
+ * Copyright (c) 2012 Savoir-faire Linux Inc.
+ * Vivien Didelot <vivien....@savoirfairelinux.com>
+ *
+ * For further information, see the Documentation/hwmon/ads7828 file.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _PDATA_ADS7828_H
+#define _PDATA_ADS7828_H
+
+/**
+ * struct ads7828_platform_data - optional ADS7828 connectivity info
+ * @diff_input: Differential input mode.
+ * @ext_vref: Use an external voltage reference.
+ * @vref_mv: Voltage reference value, if external.
+ */
+struct ads7828_platform_data {
+ bool diff_input;
+ bool ext_vref;
+ unsigned int vref_mv;
+};
+
+#endif /* _PDATA_ADS7828_H */
--
1.7.11.4
Vivien Didelot
Oct 2, 2012, 6:20:03 PM10/2/12
to
From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
The ADS7830 device is almost the same as the ADS7828,
except that it does 8-bit sampling, instead of 12-bit.
This patch extends the ads7828 driver to support this chip.
Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
Documentation/hwmon/ads7828 | 12 ++++++++++--
The ADS7830 device is almost the same as the ADS7828,
except that it does 8-bit sampling, instead of 12-bit.
This patch extends the ads7828 driver to support this chip.
Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
drivers/hwmon/Kconfig | 7 ++++---
drivers/hwmon/ads7828.c | 45 ++++++++++++++++++++++++++++++++++-----------
3 files changed, 48 insertions(+), 16 deletions(-)
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828
index b35668c..51eab52 100644
--- a/Documentation/hwmon/ads7828
+++ b/Documentation/hwmon/ads7828
@@ -8,8 +8,15 @@ Supported chips:
Datasheet: Publicly available at the Texas Instruments website:
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * Texas Instruments ADS7830
+ Prefix: 'ads7830'
+ Addresses scanned: I2C 0x48, 0x49, 0x4a, 0x4b
+ Prefix: 'ads7830'
+ Datasheet: Publicly available at the Texas Instruments website:
+ http://focus.ti.com/lit/ds/symlink/ads7830.pdf
+
Authors:
Steve Hardy <sha...@redhat.com>
+ Guillaume Roguez <guillaum...@savoirfairelinux.com>
Platform data
+
Authors:
Steve Hardy <sha...@redhat.com>
+ Guillaume Roguez <guillaum...@savoirfairelinux.com>
-------------
@@ -35,9 +42,10 @@ The structure fields are:
Description
-----------
-This driver implements support for the Texas Instruments ADS7828.
+This driver implements support for the Texas Instruments ADS7828 and ADS7830.
-----------
-This driver implements support for the Texas Instruments ADS7828.
-This device is a 12-bit 8-channel A-D converter.
+The ADS7828 device is a 12-bit 8-channel A/D converter, while the ADS7830 does
+8-bit sampling.
It can operate in single ended mode (8 +ve inputs) or in differential mode,
where 4 differential pairs can be measured.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 83e3e9d..960c8c5 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1060,11 +1060,12 @@ config SENSORS_ADS1015
will be called ads1015.
config SENSORS_ADS7828
- tristate "Texas Instruments ADS7828"
+ tristate "Texas Instruments ADS7828 and compatibles"
depends on I2C
help
- If you say yes here you get support for Texas Instruments ADS7828
- 12-bit 8-channel ADC device.
+ If you say yes here you get support for Texas Instruments ADS7828 and
+ ADS7830 8-channel A/D converters. ADS7828 resolution is 12-bit, while
+ it is 8-bit on ADS7830.
This driver can also be built as a module. If so, the module
will be called ads7828.
index 0a13bf8..809c065 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -1,11 +1,13 @@
/*
- * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC
+ * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles
* (C) 2007 EADS Astrium
*
* This driver is based on the lm75 and other lm_sensors/hwmon drivers
+ * ADS7830 support, by Guillaume Roguez <guillaum...@savoirfairelinux.com>
/*
- * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC
+ * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles
* (C) 2007 EADS Astrium
*
* This driver is based on the lm75 and other lm_sensors/hwmon drivers
+ *
* For further information, see the Documentation/hwmon/ads7828 file.
*
* This program is free software; you can redistribute it and/or modify
@@ -43,6 +45,9 @@
*
* This program is free software; you can redistribute it and/or modify
#define ADS7828_EXT_VREF_MV_MIN 50 /* External vref min value 0.05V */
#define ADS7828_EXT_VREF_MV_MAX 5250 /* External vref max value 5.25V */
+/* List of supported devices */
+enum ads7828_chips { ads7828, ads7830 };
+
+enum ads7828_chips { ads7828, ads7830 };
+
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
I2C_CLIENT_END };
@@ -59,6 +64,7 @@ struct ads7828_data {
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
I2C_CLIENT_END };
unsigned int vref_mv; /* voltage reference value */
u8 cmd_byte; /* Command byte without channel bits */
unsigned int lsb_resol; /* Resolution of the ADC sample LSB */
+ s32 (*read_channel)(const struct i2c_client *client, u8 command);
};
};
/* Command byte C2,C1,C0 - see datasheet */
@@ -82,8 +88,7 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
for (ch = 0; ch < ADS7828_NCH; ch++) {
u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch);
- data->adc_input[ch] =
- i2c_smbus_read_word_swapped(client, cmd);
+ data->adc_input[ch] = data->read_channel(client, cmd);
- i2c_smbus_read_word_swapped(client, cmd);
}
data->last_updated = jiffies;
data->valid = true;
@@ -148,6 +153,7 @@ static int ads7828_detect(struct i2c_client *client,
{
struct i2c_adapter *adapter = client->adapter;
struct i2c_adapter *adapter = client->adapter;
u8 default_cmd_byte = ADS7828_CMD_SD_SE | ADS7828_CMD_PD3;
+ bool is_8bit = false;
int ch;
/* Check we have a valid client */
@@ -159,7 +165,9 @@ static int ads7828_detect(struct i2c_client *client,
/* Check we have a valid client */
* dedicated register so attempt to sanity check using knowledge of
* the chip
* - Read from the 8 channel addresses
- * - Check the top 4 bits of each result are not set (12 data bits)
+ * - Check the top 4 bits of each result:
+ * - They should not be set in case of 12-bit samples
+ * - The two bytes should be equal in case of 8-bit samples
* the chip
* - Read from the 8 channel addresses
- * - Check the top 4 bits of each result are not set (12 data bits)
+ * - Check the top 4 bits of each result:
+ * - They should not be set in case of 12-bit samples
+ * - The two bytes should be equal in case of 8-bit samples
*/
for (ch = 0; ch < ADS7828_NCH; ch++) {
for (ch = 0; ch < ADS7828_NCH; ch++) {
u8 cmd = ads7828_cmd_byte(default_cmd_byte, ch);
@@ -169,13 +177,20 @@ static int ads7828_detect(struct i2c_client *client,
return -ENODEV;
if (in_data & 0xF000) {
- pr_debug("%s : Doesn't look like an ads7828 device\n",
- __func__);
- return -ENODEV;
+ if ((in_data >> 8) == (in_data & 0xFF)) {
+ /* Seems to be an ADS7830 (8-bit sample) */
+ is_8bit = true;
+ dev_dbg(&client->dev, "doesn't look like an ADS7828 compatible device\n");
+ return -ENODEV;
+ }
}
}
- strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
+ if (is_8bit)
+ strlcpy(info->type, "ads7830", I2C_NAME_SIZE);
+ else
+ strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
return 0;
}
@@ -207,7 +222,14 @@ static int ads7828_probe(struct i2c_client *client,
+ }
}
}
- strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
+ if (is_8bit)
+ strlcpy(info->type, "ads7830", I2C_NAME_SIZE);
+ else
+ strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
return 0;
}
else
data->vref_mv = ADS7828_INT_VREF_MV;
- data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+ /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
+ if (id->driver_data == ads7828) {
+ if (id->driver_data == ads7828) {
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+ data->read_channel = i2c_smbus_read_word_swapped;
+ } else {
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 256);
+ data->read_channel = i2c_smbus_read_byte_data;
+ }
data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
if (!data->diff_input)
data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
@@ -234,7 +256,8 @@ error:
}
static const struct i2c_device_id ads7828_ids[] = {
static const struct i2c_device_id ads7828_ids[] = {
- { "ads7828", 0 },
+ { "ads7828", ads7828 },
+ { "ads7830", ads7830 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ads7828_ids);
@@ -264,5 +287,5 @@ static void __exit sensors_ads7828_exit(void)
+ { "ads7830", ads7830 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ads7828_ids);
-MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles");
MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles");
MODULE_LICENSE("GPL");
Guenter Roeck
Oct 2, 2012, 8:30:02 PM10/2/12
to
On Tue, Oct 02, 2012 at 06:10:02PM -0400, Vivien Didelot wrote:
> * Remove module parameters, add a ads7828_platform_data;
> * Move driver declaration to avoid adding function prototypes;
> * Remove unused macros;
> * Coding Style fixes.
>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Hi Vivien,
> * Remove module parameters, add a ads7828_platform_data;
> * Move driver declaration to avoid adding function prototypes;
> * Remove unused macros;
> * Coding Style fixes.
>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
nice cleanup. Couple of minor comments below.
Please reparent.
Vivien Didelot
Oct 2, 2012, 10:30:01 PM10/2/12
to
Hi Guenter,
Some of those changes weren't in the mainline tree a few days ago.
I'll cherry-pick them and send a update very soon :-)
Thanks for the tips,
Vivien
Some of those changes weren't in the mainline tree a few days ago.
I'll cherry-pick them and send a update very soon :-)
Thanks for the tips,
Vivien
Guenter Roeck
Oct 2, 2012, 11:20:02 PM10/2/12
to
On Tue, Oct 02, 2012 at 10:28:13PM -0400, Vivien Didelot wrote:
> Hi Guenter,
>
> Some of those changes weren't in the mainline tree a few days ago.
> I'll cherry-pick them and send a update very soon :-)
>
True, but they have been in -next for the last two months or so ...
> Hi Guenter,
>
> Some of those changes weren't in the mainline tree a few days ago.
> I'll cherry-pick them and send a update very soon :-)
>
Guenter
Vivien Didelot
Oct 2, 2012, 11:40:01 PM10/2/12
to
From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
The ADS7830 device is almost the same as the ADS7828,
except that it does 8-bit sampling, instead of 12-bit.
This patch extends the ads7828 driver to support this chip.
Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
---
Documentation/hwmon/ads7828 | 12 ++++++++++--
drivers/hwmon/Kconfig | 7 ++++---
drivers/hwmon/ads7828.c | 45 ++++++++++++++++++++++++++++++++++-----------
3 files changed, 48 insertions(+), 16 deletions(-)
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828
The ADS7830 device is almost the same as the ADS7828,
except that it does 8-bit sampling, instead of 12-bit.
This patch extends the ads7828 driver to support this chip.
Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
---
Documentation/hwmon/ads7828 | 12 ++++++++++--
drivers/hwmon/Kconfig | 7 ++++---
drivers/hwmon/ads7828.c | 45 ++++++++++++++++++++++++++++++++++-----------
3 files changed, 48 insertions(+), 16 deletions(-)
index b35668c..51eab52 100644
--- a/Documentation/hwmon/ads7828
+++ b/Documentation/hwmon/ads7828
@@ -8,8 +8,15 @@ Supported chips:
Datasheet: Publicly available at the Texas Instruments website:
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * Texas Instruments ADS7830
+ Prefix: 'ads7830'
+ Addresses scanned: I2C 0x48, 0x49, 0x4a, 0x4b
+ Prefix: 'ads7830'
+ Datasheet: Publicly available at the Texas Instruments website:
index 756bd1b..638c969 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -1,11 +1,13 @@
/*
- * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC
+ * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles
* (C) 2007 EADS Astrium
*
* This driver is based on the lm75 and other lm_sensors/hwmon drivers
/*
- * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC
+ * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles
* (C) 2007 EADS Astrium
*
* This driver is based on the lm75 and other lm_sensors/hwmon drivers
* For further information, see the Documentation/hwmon/ads7828 file.
*
* This program is free software; you can redistribute it and/or modify
@@ -43,6 +45,9 @@
*
* This program is free software; you can redistribute it and/or modify
#define ADS7828_EXT_VREF_MV_MIN 50 /* External vref min value 0.05V */
#define ADS7828_EXT_VREF_MV_MAX 5250 /* External vref max value 5.25V */
+/* List of supported devices */
+enum ads7828_chips { ads7828, ads7830 };
+
+enum ads7828_chips { ads7828, ads7830 };
+
/* Addresses to scan */
static const unsigned short ads7828_normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
I2C_CLIENT_END };
@@ -59,6 +64,7 @@ struct ads7828_data {
unsigned int vref_mv; /* voltage reference value */
u8 cmd_byte; /* Command byte without channel bits */
unsigned int lsb_resol; /* Resolution of the ADC sample LSB */
+ s32 (*read_channel)(const struct i2c_client *client, u8 command);
};
};
/* Command byte C2,C1,C0 - see datasheet */
@@ -82,8 +88,7 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
for (ch = 0; ch < ADS7828_NCH; ch++) {
u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch);
- data->adc_input[ch] =
- i2c_smbus_read_word_swapped(client, cmd);
+ data->adc_input[ch] = data->read_channel(client, cmd);
- i2c_smbus_read_word_swapped(client, cmd);
}
data->last_updated = jiffies;
data->valid = true;
@@ -147,6 +152,7 @@ static int ads7828_detect(struct i2c_client *client,
{
struct i2c_adapter *adapter = client->adapter;
struct i2c_adapter *adapter = client->adapter;
u8 default_cmd_byte = ADS7828_CMD_SD_SE | ADS7828_CMD_PD3;
+ bool is_8bit = false;
int ch;
/* Check we have a valid client */
@@ -158,7 +164,9 @@ static int ads7828_detect(struct i2c_client *client,
/* Check we have a valid client */
* dedicated register so attempt to sanity check using knowledge of
* the chip
* - Read from the 8 channel addresses
- * - Check the top 4 bits of each result are not set (12 data bits)
+ * - Check the top 4 bits of each result:
+ * - They should not be set in case of 12-bit samples
+ * - The two bytes should be equal in case of 8-bit samples
* the chip
* - Read from the 8 channel addresses
- * - Check the top 4 bits of each result are not set (12 data bits)
+ * - Check the top 4 bits of each result:
+ * - They should not be set in case of 12-bit samples
+ * - The two bytes should be equal in case of 8-bit samples
*/
for (ch = 0; ch < ADS7828_NCH; ch++) {
for (ch = 0; ch < ADS7828_NCH; ch++) {
u8 cmd = ads7828_cmd_byte(default_cmd_byte, ch);
@@ -168,13 +176,20 @@ static int ads7828_detect(struct i2c_client *client,
return -ENODEV;
if (in_data & 0xF000) {
- pr_debug("%s : Doesn't look like an ads7828 device\n",
- __func__);
- return -ENODEV;
+ if ((in_data >> 8) == (in_data & 0xFF)) {
+ /* Seems to be an ADS7830 (8-bit sample) */
+ is_8bit = true;
+ } else {
+ dev_dbg(&client->dev, "doesn't look like an ADS7828 compatible device\n");
+ return -ENODEV;
+ }
}
}
- strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
+ if (is_8bit)
+ strlcpy(info->type, "ads7830", I2C_NAME_SIZE);
+ else
+ strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
return 0;
}
@@ -206,7 +221,14 @@ static int ads7828_probe(struct i2c_client *client,
if (in_data & 0xF000) {
- pr_debug("%s : Doesn't look like an ads7828 device\n",
- __func__);
- return -ENODEV;
+ if ((in_data >> 8) == (in_data & 0xFF)) {
+ /* Seems to be an ADS7830 (8-bit sample) */
+ is_8bit = true;
+ } else {
+ dev_dbg(&client->dev, "doesn't look like an ADS7828 compatible device\n");
+ return -ENODEV;
+ }
}
}
- strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
+ if (is_8bit)
+ strlcpy(info->type, "ads7830", I2C_NAME_SIZE);
+ else
+ strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
return 0;
}
else
data->vref_mv = ADS7828_INT_VREF_MV;
- data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+ /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
+ if (id->driver_data == ads7828) {
data->vref_mv = ADS7828_INT_VREF_MV;
- data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+ /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
+ if (id->driver_data == ads7828) {
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+ data->read_channel = i2c_smbus_read_word_swapped;
+ } else {
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 256);
+ data->read_channel = i2c_smbus_read_byte_data;
+ } else {
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 256);
+ data->read_channel = i2c_smbus_read_byte_data;
+ }
data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
if (!data->diff_input)
data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
@@ -233,7 +255,8 @@ error:
}
static const struct i2c_device_id ads7828_device_ids[] = {
- { "ads7828", 0 },
+ { "ads7828", ads7828 },
+ { "ads7830", ads7830 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ads7828_device_ids);
+ { "ads7830", ads7830 },
{ }
};
@@ -254,4 +277,4 @@ module_i2c_driver(ads7828_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Steve Hardy <sha...@redhat.com>");
-MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles");
--
1.7.11.4
Vivien Didelot
Oct 2, 2012, 11:40:02 PM10/2/12
to
* Remove module parameters, add a ads7828_platform_data;
* Move driver declaration to avoid adding function prototypes;
* Remove unused macros;
* Coding Style fixes.
Documentation/hwmon/ads7828 | 31 +++--
* Move driver declaration to avoid adding function prototypes;
* Remove unused macros;
* Coding Style fixes.
drivers/hwmon/ads7828.c | 206 ++++++++++++++++------------------
include/linux/platform_data/ads7828.h | 29 +++++
3 files changed, 147 insertions(+), 119 deletions(-)
create mode 100644 include/linux/platform_data/ads7828.h
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828
index 2bbebe6..b35668c 100644
--- a/Documentation/hwmon/ads7828
+++ b/Documentation/hwmon/ads7828
@@ -5,21 +5,32 @@ Supported chips:
* Texas Instruments/Burr-Brown ADS7828
Prefix: 'ads7828'
* Texas Instruments/Burr-Brown ADS7828
Prefix: 'ads7828'
Addresses scanned: I2C 0x48, 0x49, 0x4a, 0x4b
- Datasheet: Publicly available at the Texas Instruments website :
+ Datasheet: Publicly available at the Texas Instruments website:
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
index 1f9e8af..756bd1b 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -6,7 +6,7 @@
- * Datasheet available at: http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * For further information, see the Documentation/hwmon/ads7828 file.
*
* This program is free software; you can redistribute it and/or modify
* This program is free software; you can redistribute it and/or modify
+#define ADS7828_EXT_VREF_MV_MAX 5250 /* External vref max value 5.25V */
/* Addresses to scan */
+static const unsigned short ads7828_normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
I2C_CLIENT_END };
for (ch = 0; ch < ADS7828_NCH; ch++) {
- u8 cmd = channel_cmd_byte(ch);
+ u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch);
data->adc_input[ch] =
i2c_smbus_read_word_swapped(client, cmd);
+ u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch);
data->adc_input[ch] =
}
data->last_updated = jiffies;
static int ads7828_remove(struct i2c_client *client)
{
struct ads7828_data *data = i2c_get_clientdata(client);
+
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
+
{
struct ads7828_data *data = i2c_get_clientdata(client);
+
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
return 0;
}
-static const struct i2c_device_id ads7828_id[] = {
- { "ads7828", 0 },
- { }
-};
-MODULE_DEVICE_TABLE(i2c, ads7828_id);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver ads7828_driver = {
- .class = I2C_CLASS_HWMON,
- .driver = {
- .name = "ads7828",
- },
- .probe = ads7828_probe,
- .remove = ads7828_remove,
- .id_table = ads7828_id,
- .detect = ads7828_detect,
- .address_list = normal_i2c,
-};
-
/* Return 0 if detection is successful, -ENODEV otherwise */
-};
-MODULE_DEVICE_TABLE(i2c, ads7828_id);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver ads7828_driver = {
- .class = I2C_CLASS_HWMON,
- .driver = {
- .name = "ads7828",
- },
- .probe = ads7828_probe,
- .remove = ads7828_remove,
- .id_table = ads7828_id,
- .detect = ads7828_detect,
- .address_list = normal_i2c,
-};
-
/* Return 0 if detection is successful, -ENODEV otherwise */
static int ads7828_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
+ u8 default_cmd_byte = ADS7828_CMD_SD_SE | ADS7828_CMD_PD3;
struct i2c_adapter *adapter = client->adapter;
int ch;
/* Check we have a valid client */
@@ -195,9 +161,12 @@ static int ads7828_detect(struct i2c_client *client,
/* Check we have a valid client */
* - Check the top 4 bits of each result are not set (12 data bits)
*/
for (ch = 0; ch < ADS7828_NCH; ch++) {
for (ch = 0; ch < ADS7828_NCH; ch++) {
- u16 in_data;
- u8 cmd = channel_cmd_byte(ch);
- in_data = i2c_smbus_read_word_swapped(client, cmd);
+ u8 cmd = ads7828_cmd_byte(default_cmd_byte, ch);
+ u16 in_data = i2c_smbus_read_word_swapped(client, cmd);
+
+ if (in_data < 0)
+ return -ENODEV;
+
if (in_data & 0xF000) {
- u8 cmd = channel_cmd_byte(ch);
- in_data = i2c_smbus_read_word_swapped(client, cmd);
+ u8 cmd = ads7828_cmd_byte(default_cmd_byte, ch);
+ u16 in_data = i2c_smbus_read_word_swapped(client, cmd);
+
+ if (in_data < 0)
+ return -ENODEV;
+
if (in_data & 0xF000) {
pr_debug("%s : Doesn't look like an ads7828 device\n",
__func__);
@@ -213,6 +182,7 @@ static int ads7828_detect(struct i2c_client *client,
static int ads7828_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
+ struct ads7828_platform_data *pdata = client->dev.platform_data;
struct ads7828_data *data;
int err;
@@ -221,10 +191,30 @@ static int ads7828_probe(struct i2c_client *client,
int err;
if (!data)
return -ENOMEM;
+ if (pdata) {
+ data->diff_input = pdata->diff_input;
+ data->ext_vref = pdata->ext_vref;
+ if (data->ext_vref)
+ data->vref_mv = pdata->vref_mv;
+ }
+ /* Bound Vref with min/max values if it was provided */
+ if (data->vref_mv)
+ data->vref_mv = SENSORS_LIMIT(data->vref_mv,
+ ADS7828_EXT_VREF_MV_MIN,
+ ADS7828_EXT_VREF_MV_MAX);
+ else
+ data->vref_mv = ADS7828_INT_VREF_MV;
+
+ if (data->vref_mv)
+ data->vref_mv = SENSORS_LIMIT(data->vref_mv,
+ ADS7828_EXT_VREF_MV_MIN,
+ ADS7828_EXT_VREF_MV_MAX);
+ else
+ data->vref_mv = ADS7828_INT_VREF_MV;
+
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+
+
+ data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
+ if (!data->diff_input)
+ data->cmd_byte |= ADS7828_CMD_SD_SE;
+
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
- /* Register sysfs hooks */
err = sysfs_create_group(&client->dev.kobj, &ads7828_group);
if (err)
return err;
+ data->cmd_byte |= ADS7828_CMD_SD_SE;
+
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
- /* Register sysfs hooks */
err = sysfs_create_group(&client->dev.kobj, &ads7828_group);
if (err)
@@ -232,38 +222,36 @@ static int ads7828_probe(struct i2c_client *client,
data->hwmon_dev = hwmon_device_register(&client->dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
- goto exit_remove;
+ goto error;
}
return 0;
-exit_remove:
+error:
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
- goto exit_remove;
+ goto error;
}
return 0;
-exit_remove:
+error:
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
return err;
}
-static int __init sensors_ads7828_init(void)
-{
- /* Initialize the command byte according to module parameters */
- ads7828_cmd_byte = se_input ?
- ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
- ads7828_cmd_byte |= int_vref ?
- ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
-
}
-static int __init sensors_ads7828_init(void)
-{
- /* Initialize the command byte according to module parameters */
- ads7828_cmd_byte = se_input ?
- ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
- ads7828_cmd_byte |= int_vref ?
- ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
- /* Calculate the LSB resolution */
- ads7828_lsb_resol = (vref_mv*1000)/4096;
+static const struct i2c_device_id ads7828_device_ids[] = {
- ads7828_lsb_resol = (vref_mv*1000)/4096;
+ { "ads7828", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ads7828_device_ids);
- return i2c_add_driver(&ads7828_driver);
-}
+static struct i2c_driver ads7828_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "ads7828",
+ },
+ .address_list = ads7828_normal_i2c,
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "ads7828",
+ },
+ .detect = ads7828_detect,
+ .probe = ads7828_probe,
+ .remove = ads7828_remove,
+ .id_table = ads7828_device_ids,
+ .probe = ads7828_probe,
+ .remove = ads7828_remove,
+};
-static void __exit sensors_ads7828_exit(void)
-{
- i2c_del_driver(&ads7828_driver);
-}
+module_i2c_driver(ads7828_driver);
-MODULE_AUTHOR("Steve Hardy <sha...@redhat.com>");
-MODULE_DESCRIPTION("ADS7828 driver");
MODULE_LICENSE("GPL");
-
-module_init(sensors_ads7828_init);
-module_exit(sensors_ads7828_exit);
+MODULE_AUTHOR("Steve Hardy <sha...@redhat.com>");
-
-module_init(sensors_ads7828_init);
-module_exit(sensors_ads7828_exit);
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
Guenter Roeck
Oct 3, 2012, 12:50:01 AM10/3/12
to
On Tue, Oct 02, 2012 at 11:33:26PM -0400, Vivien Didelot wrote:
> * Remove module parameters, add a ads7828_platform_data;
> * Move driver declaration to avoid adding function prototypes;
> * Remove unused macros;
> * Coding Style fixes.
>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Hi Vivien,
> * Remove module parameters, add a ads7828_platform_data;
> * Move driver declaration to avoid adding function prototypes;
> * Remove unused macros;
> * Coding Style fixes.
>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
nice cleanup.
One more comment below. No need to re-send; I'll fix that and apply the patch to
-next.
Guenter
[ ... ]
> /* Return 0 if detection is successful, -ENODEV otherwise */
> static int ads7828_detect(struct i2c_client *client,
> struct i2c_board_info *info)
> {
> struct i2c_adapter *adapter = client->adapter;
> + u8 default_cmd_byte = ADS7828_CMD_SD_SE | ADS7828_CMD_PD3;
> int ch;
>
> /* Check we have a valid client */
> @@ -195,9 +161,12 @@ static int ads7828_detect(struct i2c_client *client,
> * - Check the top 4 bits of each result are not set (12 data bits)
> */
> for (ch = 0; ch < ADS7828_NCH; ch++) {
> - u16 in_data;
> - u8 cmd = channel_cmd_byte(ch);
> - in_data = i2c_smbus_read_word_swapped(client, cmd);
> + u8 cmd = ads7828_cmd_byte(default_cmd_byte, ch);
> + u16 in_data = i2c_smbus_read_word_swapped(client, cmd);
Otherwise in_data can never be < 0.
Guenter
Guenter Roeck
Oct 3, 2012, 1:10:01 AM10/3/12
to
On Tue, Oct 02, 2012 at 11:33:27PM -0400, Vivien Didelot wrote:
> From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
>
> The ADS7830 device is almost the same as the ADS7828,
> except that it does 8-bit sampling, instead of 12-bit.
> This patch extends the ads7828 driver to support this chip.
>
> Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Guillaume,
> From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
>
> The ADS7830 device is almost the same as the ADS7828,
> except that it does 8-bit sampling, instead of 12-bit.
> This patch extends the ads7828 driver to support this chip.
>
> Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Vivien,
[ ... ]
and this makes it even weaker. Reason is that you conly check for ADS7830 if the
check for ADS7828 failed, and you repeat the pattern for each channel.
Unfortunately, that means that you don't check for the ADS7830 condition if the
value returned for a channel happens to be a valid ADS7828 value, even if it is
not valid for ADS7830 (and even if you already know that the chip is not a
ADS7828).
Example:
ch=0: 0x1818 --> You know it is not ADS7828
ch=1: 0x0818 --> You know it is not ADS7830, but you don't check for it
I don't know an optimal solution right now, but maybe something like
maybe_7828 = true;
maybe_7830 = true;
for (ch = 0; ch < ADS7828_NCH && (maybe_7828 || maybe_7830); ch++) {
...
if (in_data & 0xF000)
maybe_7828 = false;
if ((in_data >> 8) != (in_data & 0xFF))
maybe_7830 = false;
}
if (!maybe_7828 && !maybe_7830)
return -ENODEV;
if (maybe_7828)
strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
else
strlcpy(info->type, "ads7830", I2C_NAME_SIZE);
Frankly I would prefer to get rid of the _detect function entirely, I just don't
know if that would negatively affect some users. To give you an example for a
bad result: The function will wrongly detect an ADS7830 as ADS7828 if all ADC
channels report a value between 0x00 and 0x0f.
How do you use the chip ? Do you need the detect function in your application ?
Thanks,
Guenter
Vivien Didelot
Oct 3, 2012, 10:10:02 AM10/3/12
to
Hi Guenter,
We totally agree with you here. There is no clean way to detect (i.e. to
be sure) that this *is* an ADS7828 compatible device.
> How do you use the chip ? Do you need the detect function in your application ?
In our application, this device is statically declared in the platform
support code, so we don't need to "detect" it.
I propose to re-send a v5 with the "s/u16 in_data/int in_data/" fix and
the ads7828_detect() removal in the first cleanup patch, then the
ADS7830 support. Does it sound good for you?
Thanks,
Vivien
be sure) that this *is* an ADS7828 compatible device.
> How do you use the chip ? Do you need the detect function in your application ?
support code, so we don't need to "detect" it.
I propose to re-send a v5 with the "s/u16 in_data/int in_data/" fix and
the ads7828_detect() removal in the first cleanup patch, then the
ADS7830 support. Does it sound good for you?
Thanks,
Vivien
Guenter Roeck
Oct 3, 2012, 11:20:01 AM10/3/12
to
Thanks,
Guenter
Vivien Didelot
Oct 3, 2012, 5:00:02 PM10/3/12
to
From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
The ADS7830 device is almost the same as the ADS7828,
except that it does 8-bit sampling, instead of 12-bit.
This patch extends the ads7828 driver to support this chip.
Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
---
The ADS7830 device is almost the same as the ADS7828,
except that it does 8-bit sampling, instead of 12-bit.
This patch extends the ads7828 driver to support this chip.
Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Documentation/hwmon/ads7828 | 11 +++++++++--
drivers/hwmon/Kconfig | 7 ++++---
drivers/hwmon/ads7828.c | 25 +++++++++++++++++++------
3 files changed, 32 insertions(+), 11 deletions(-)
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828
index a987c94..f6e263e 100644
--- a/Documentation/hwmon/ads7828
+++ b/Documentation/hwmon/ads7828
@@ -7,9 +7,15 @@ Supported chips:
Datasheet: Publicly available at the Texas Instruments website:
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * Texas Instruments ADS7830
+ Prefix: 'ads7830'
+ Prefix: 'ads7830'
+ Datasheet: Publicly available at the Texas Instruments website:
Vivien Didelot <vivien....@savoirfairelinux.com>
@@ -35,9 +41,10 @@ in include/linux/platform_data/ads7828.h). The structure fields are:
index 42914fc..409b5c1 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -1,11 +1,13 @@
/*
- * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC
+ * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles
* (C) 2007 EADS Astrium
*
* This driver is based on the lm75 and other lm_sensors/hwmon drivers
/*
- * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC
+ * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles
* (C) 2007 EADS Astrium
*
* This driver is based on the lm75 and other lm_sensors/hwmon drivers
* For further information, see the Documentation/hwmon/ads7828 file.
*
* This program is free software; you can redistribute it and/or modify
@@ -43,6 +45,9 @@
*
* This program is free software; you can redistribute it and/or modify
#define ADS7828_EXT_VREF_MV_MIN 50 /* External vref min value 0.05V */
#define ADS7828_EXT_VREF_MV_MAX 5250 /* External vref max value 5.25V */
+/* List of supported devices */
+enum ads7828_chips { ads7828, ads7830 };
+
+enum ads7828_chips { ads7828, ads7830 };
+
/* Client specific data */
struct ads7828_data {
struct device *hwmon_dev;
@@ -55,6 +60,7 @@ struct ads7828_data {
struct ads7828_data {
struct device *hwmon_dev;
unsigned int vref_mv; /* voltage reference value */
u8 cmd_byte; /* Command byte without channel bits */
unsigned int lsb_resol; /* Resolution of the ADC sample LSB */
+ s32 (*read_channel)(const struct i2c_client *client, u8 command);
};
};
/* Command byte C2,C1,C0 - see datasheet */
@@ -78,8 +84,7 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
for (ch = 0; ch < ADS7828_NCH; ch++) {
u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch);
- data->adc_input[ch] =
- i2c_smbus_read_word_swapped(client, cmd);
+ data->adc_input[ch] = data->read_channel(client, cmd);
- data->adc_input[ch] =
- i2c_smbus_read_word_swapped(client, cmd);
}
data->last_updated = jiffies;
data->valid = true;
@@ -164,7 +169,14 @@ static int ads7828_probe(struct i2c_client *client,
else
data->vref_mv = ADS7828_INT_VREF_MV;
- data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+ /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
+ if (id->driver_data == ads7828) {
data->vref_mv = ADS7828_INT_VREF_MV;
- data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+ /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
+ if (id->driver_data == ads7828) {
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+ data->read_channel = i2c_smbus_read_word_swapped;
+ } else {
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 256);
+ data->read_channel = i2c_smbus_read_byte_data;
+ } else {
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 256);
+ data->read_channel = i2c_smbus_read_byte_data;
+ }
data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
if (!data->diff_input)
data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
@@ -191,7 +203,8 @@ error:
}
static const struct i2c_device_id ads7828_device_ids[] = {
static const struct i2c_device_id ads7828_device_ids[] = {
- { "ads7828", 0 },
+ { "ads7828", ads7828 },
+ { "ads7830", ads7830 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ads7828_device_ids);
@@ -210,4 +223,4 @@ module_i2c_driver(ads7828_driver);
+ { "ads7830", ads7830 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ads7828_device_ids);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Steve Hardy <sha...@redhat.com>");
-MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles");
--
1.7.11.4
+MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles");
--
1.7.11.4
Vivien Didelot
Oct 3, 2012, 5:00:03 PM10/3/12
to
As there is no reliable way to identify the chip, it is preferable to
remove the detect callback, to avoid misdetection.
Module parameters are not worth it here, so let's get rid of them and
add an ads7828_platform_data structure instead.
Clean the code by removing unused macros, fixing coding style issues,
avoiding function prototypes and using convenient macros such as
module_i2c_driver().
Documentation/hwmon/ads7828 | 35 ++++--
drivers/hwmon/ads7828.c | 228 +++++++++++++---------------------
include/linux/platform_data/ads7828.h | 29 +++++
3 files changed, 140 insertions(+), 152 deletions(-)
create mode 100644 include/linux/platform_data/ads7828.h
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828
index 2bbebe6..a987c94 100644
--- a/Documentation/hwmon/ads7828
+++ b/Documentation/hwmon/ads7828
@@ -4,22 +4,33 @@ Kernel driver ads7828
- Datasheet: Publicly available at the Texas Instruments website :
+ Datasheet: Publicly available at the Texas Instruments website:
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
Authors:
Steve Hardy <sha...@redhat.com>
+ Vivien Didelot <vivien....@savoirfairelinux.com>
-Module Parameters
------------------
+Platform data
+-------------
-* se_input: bool (default Y)
- Single ended operation - set to N for differential mode
-* int_vref: bool (default Y)
- Operate with the internal 2.5V reference - set to N for external reference
-* vref_mv: int (default 2500)
- If using an external reference, set this to the reference voltage in mV
+
+* diff_input: (bool) Differential operation
+ set to true for differential mode, false for default single ended mode.
+
+* ext_vref: (bool) External reference
+ set to true if it operates with an external reference, false for default
+ internal reference.
+
+* vref_mv: (unsigned int) Voltage reference
+ if using an external reference, set this to the reference voltage in mV,
+ otherwise it will default to the internal value (2500mV). This value will be
+ bounded with limits accepted by the chip, described in the datasheet.
+
+ If no structure is provided, the configuration defaults to single ended
+ operation and internal voltage reference (2.5V).
Description
-----------
@@ -34,3 +45,7 @@ where 4 differential pairs can be measured.
The chip also has the facility to use an external voltage reference. This
may be required if your hardware supplies the ADS7828 from a 5V supply, see
the datasheet for more details.
+
+There is no reliable way to identify this chip, so the driver will not scan
+some addresses to try to auto-detect it. That means that you will have to
+statically declare the device in the platform support code.
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index 1f9e8af..42914fc 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -6,7 +6,7 @@
-
-/* Addresses to scan */
-
+#define ADS7828_EXT_VREF_MV_MAX 5250 /* External vref max value 5.25V */
+
+/* Client specific data */
@@ -96,12 +77,12 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
}
data->last_updated = jiffies;
@@ -152,60 +130,9 @@ static const struct attribute_group ads7828_group = {
-}
-
-static const struct i2c_device_id ads7828_id[] = {
- struct i2c_adapter *adapter = client->adapter;
- int ch;
-
- /* Check we have a valid client */
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA))
- return -ENODEV;
-
- /*
- * Now, we do the remaining detection. There is no identification
- * dedicated register so attempt to sanity check using knowledge of
- * the chip
- * - Read from the 8 channel addresses
- for (ch = 0; ch < ADS7828_NCH; ch++) {
- }
-
- strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
return 0;
}
@@ -213,6 +140,7 @@ static int ads7828_detect(struct i2c_client *client,
+ { "ads7828", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ads7828_device_ids);
- /* Calculate the LSB resolution */
- ads7828_lsb_resol = (vref_mv*1000)/4096;
-}
remove the detect callback, to avoid misdetection.
Module parameters are not worth it here, so let's get rid of them and
add an ads7828_platform_data structure instead.
Clean the code by removing unused macros, fixing coding style issues,
avoiding function prototypes and using convenient macros such as
module_i2c_driver().
Documentation/hwmon/ads7828 | 35 ++++--
drivers/hwmon/ads7828.c | 228 +++++++++++++---------------------
include/linux/platform_data/ads7828.h | 29 +++++
3 files changed, 140 insertions(+), 152 deletions(-)
create mode 100644 include/linux/platform_data/ads7828.h
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828
index 2bbebe6..a987c94 100644
--- a/Documentation/hwmon/ads7828
+++ b/Documentation/hwmon/ads7828
@@ -4,22 +4,33 @@ Kernel driver ads7828
Supported chips:
* Texas Instruments/Burr-Brown ADS7828
Prefix: 'ads7828'
- Addresses scanned: I2C 0x48, 0x49, 0x4a, 0x4b
* Texas Instruments/Burr-Brown ADS7828
Prefix: 'ads7828'
- Datasheet: Publicly available at the Texas Instruments website :
+ Datasheet: Publicly available at the Texas Instruments website:
http://focus.ti.com/lit/ds/symlink/ads7828.pdf
Authors:
Steve Hardy <sha...@redhat.com>
+ Vivien Didelot <vivien....@savoirfairelinux.com>
-Module Parameters
------------------
+Platform data
+-------------
-* se_input: bool (default Y)
- Single ended operation - set to N for differential mode
-* int_vref: bool (default Y)
- Operate with the internal 2.5V reference - set to N for external reference
-* vref_mv: int (default 2500)
- If using an external reference, set this to the reference voltage in mV
+The ads7828 driver accepts an optional ads7828_platform_data structure (defined
+in include/linux/platform_data/ads7828.h). The structure fields are:
+
+* diff_input: (bool) Differential operation
+ set to true for differential mode, false for default single ended mode.
+
+* ext_vref: (bool) External reference
+ set to true if it operates with an external reference, false for default
+ internal reference.
+
+* vref_mv: (unsigned int) Voltage reference
+ if using an external reference, set this to the reference voltage in mV,
+ otherwise it will default to the internal value (2500mV). This value will be
+ bounded with limits accepted by the chip, described in the datasheet.
+
+ If no structure is provided, the configuration defaults to single ended
+ operation and internal voltage reference (2.5V).
Description
-----------
@@ -34,3 +45,7 @@ where 4 differential pairs can be measured.
The chip also has the facility to use an external voltage reference. This
may be required if your hardware supplies the ADS7828 from a 5V supply, see
the datasheet for more details.
+
+There is no reliable way to identify this chip, so the driver will not scan
+some addresses to try to auto-detect it. That means that you will have to
+statically declare the device in the platform support code.
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index 1f9e8af..42914fc 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -6,7 +6,7 @@
- * Datasheet available at: http://focus.ti.com/lit/ds/symlink/ads7828.pdf
+ * For further information, see the Documentation/hwmon/ads7828 file.
*
* This program is free software; you can redistribute it and/or modify
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -23,63 +23,44 @@
-/* Addresses to scan */
-static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
- I2C_CLIENT_END };
-
-/* Module parameters */
-static bool se_input = 1; /* Default is SE, 0 == diff */
-static bool int_vref = 1; /* Default is internal ref ON */
-static int vref_mv = ADS7828_INT_VREF_MV; /* set if vref != 2.5V */
-module_param(se_input, bool, S_IRUGO);
-module_param(int_vref, bool, S_IRUGO);
-module_param(vref_mv, int, S_IRUGO);
-
-/* Global Variables */
-static u8 ads7828_cmd_byte; /* cmd byte without channel bits */
-static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
-
-/* Each client has this additional data */
-static bool se_input = 1; /* Default is SE, 0 == diff */
-static bool int_vref = 1; /* Default is internal ref ON */
-static int vref_mv = ADS7828_INT_VREF_MV; /* set if vref != 2.5V */
-module_param(se_input, bool, S_IRUGO);
-module_param(int_vref, bool, S_IRUGO);
-module_param(vref_mv, int, S_IRUGO);
-
-/* Global Variables */
-static u8 ads7828_cmd_byte; /* cmd byte without channel bits */
-static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
-
-/* Each client has this additional data */
+#define ADS7828_NCH 8 /* 8 channels supported */
+#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
+#define ADS7828_CMD_PD1 0x04 /* Internal vref OFF && A/D ON */
+#define ADS7828_CMD_PD3 0x0C /* Internal vref ON && A/D ON */
+#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+#define ADS7828_EXT_VREF_MV_MIN 50 /* External vref min value 0.05V */
+#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
+#define ADS7828_CMD_PD1 0x04 /* Internal vref OFF && A/D ON */
+#define ADS7828_CMD_PD3 0x0C /* Internal vref ON && A/D ON */
+#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
+#define ADS7828_EXT_VREF_MV_MAX 5250 /* External vref max value 5.25V */
+
+/* Client specific data */
struct ads7828_data {
struct device *hwmon_dev;
struct device *hwmon_dev;
dev_dbg(&client->dev, "Starting ads7828 update\n");
for (ch = 0; ch < ADS7828_NCH; ch++) {
- u8 cmd = channel_cmd_byte(ch);
+ u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch);
data->adc_input[ch] =
i2c_smbus_read_word_swapped(client, cmd);
data->adc_input[ch] =
}
data->last_updated = jiffies;
- data->valid = 1;
+ data->valid = true;
}
mutex_unlock(&data->update_lock);
@@ -110,28 +91,25 @@ static struct ads7828_data *ads7828_update_device(struct device *dev)
+ data->valid = true;
}
mutex_unlock(&data->update_lock);
static int ads7828_remove(struct i2c_client *client)
{
struct ads7828_data *data = i2c_get_clientdata(client);
+
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
- return 0;
{
struct ads7828_data *data = i2c_get_clientdata(client);
+
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
-}
-
-static const struct i2c_device_id ads7828_id[] = {
- { "ads7828", 0 },
- { }
-};
-MODULE_DEVICE_TABLE(i2c, ads7828_id);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver ads7828_driver = {
- .class = I2C_CLASS_HWMON,
- .driver = {
- .name = "ads7828",
- },
- .probe = ads7828_probe,
- .remove = ads7828_remove,
- .id_table = ads7828_id,
- .detect = ads7828_detect,
- .address_list = normal_i2c,
-};
-
-/* Return 0 if detection is successful, -ENODEV otherwise */
-};
-MODULE_DEVICE_TABLE(i2c, ads7828_id);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver ads7828_driver = {
- .class = I2C_CLASS_HWMON,
- .driver = {
- .name = "ads7828",
- },
- .probe = ads7828_probe,
- .remove = ads7828_remove,
- .id_table = ads7828_id,
- .detect = ads7828_detect,
- .address_list = normal_i2c,
-};
-
-static int ads7828_detect(struct i2c_client *client,
- struct i2c_board_info *info)
-{
- struct i2c_board_info *info)
- struct i2c_adapter *adapter = client->adapter;
- int ch;
-
- /* Check we have a valid client */
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA))
- return -ENODEV;
-
- /*
- * Now, we do the remaining detection. There is no identification
- * dedicated register so attempt to sanity check using knowledge of
- * the chip
- * - Read from the 8 channel addresses
- * - Check the top 4 bits of each result are not set (12 data bits)
- */
- for (ch = 0; ch < ADS7828_NCH; ch++) {
- u16 in_data;
- u8 cmd = channel_cmd_byte(ch);
- in_data = i2c_smbus_read_word_swapped(client, cmd);
- if (in_data & 0xF000) {
- u8 cmd = channel_cmd_byte(ch);
- in_data = i2c_smbus_read_word_swapped(client, cmd);
- pr_debug("%s : Doesn't look like an ads7828 device\n",
- __func__);
- return -ENODEV;
- }
- __func__);
- return -ENODEV;
- }
-
- strlcpy(info->type, "ads7828", I2C_NAME_SIZE);
return 0;
}
@@ -213,6 +140,7 @@ static int ads7828_detect(struct i2c_client *client,
static int ads7828_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
+ struct ads7828_platform_data *pdata = client->dev.platform_data;
struct ads7828_data *data;
int err;
@@ -221,10 +149,30 @@ static int ads7828_probe(struct i2c_client *client,
{
+ struct ads7828_platform_data *pdata = client->dev.platform_data;
struct ads7828_data *data;
int err;
if (!data)
return -ENOMEM;
+ if (pdata) {
+ data->diff_input = pdata->diff_input;
+ data->ext_vref = pdata->ext_vref;
+ if (data->ext_vref)
+ data->vref_mv = pdata->vref_mv;
+ }
+
+ /* Bound Vref with min/max values if it was provided */
+ if (data->vref_mv)
+ data->vref_mv = SENSORS_LIMIT(data->vref_mv,
+ ADS7828_EXT_VREF_MV_MIN,
+ ADS7828_EXT_VREF_MV_MAX);
+ else
+ data->vref_mv = ADS7828_INT_VREF_MV;
+
return -ENOMEM;
+ if (pdata) {
+ data->diff_input = pdata->diff_input;
+ data->ext_vref = pdata->ext_vref;
+ if (data->ext_vref)
+ data->vref_mv = pdata->vref_mv;
+ }
+
+ /* Bound Vref with min/max values if it was provided */
+ if (data->vref_mv)
+ data->vref_mv = SENSORS_LIMIT(data->vref_mv,
+ ADS7828_EXT_VREF_MV_MIN,
+ ADS7828_EXT_VREF_MV_MAX);
+ else
+ data->vref_mv = ADS7828_INT_VREF_MV;
+
+ data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
+
+
+ data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
+ if (!data->diff_input)
+ data->cmd_byte |= ADS7828_CMD_SD_SE;
+
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
- /* Register sysfs hooks */
err = sysfs_create_group(&client->dev.kobj, &ads7828_group);
if (err)
return err;
@@ -232,38 +180,34 @@ static int ads7828_probe(struct i2c_client *client,
+ data->cmd_byte |= ADS7828_CMD_SD_SE;
+
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
- /* Register sysfs hooks */
err = sysfs_create_group(&client->dev.kobj, &ads7828_group);
if (err)
return err;
data->hwmon_dev = hwmon_device_register(&client->dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
- goto exit_remove;
+ goto error;
}
return 0;
-exit_remove:
+error:
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
return err;
}
-static int __init sensors_ads7828_init(void)
-{
- /* Initialize the command byte according to module parameters */
- ads7828_cmd_byte = se_input ?
- ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
- ads7828_cmd_byte |= int_vref ?
- ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
+static const struct i2c_device_id ads7828_device_ids[] = {
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
- goto exit_remove;
+ goto error;
}
return 0;
-exit_remove:
+error:
sysfs_remove_group(&client->dev.kobj, &ads7828_group);
return err;
}
-static int __init sensors_ads7828_init(void)
-{
- /* Initialize the command byte according to module parameters */
- ads7828_cmd_byte = se_input ?
- ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
- ads7828_cmd_byte |= int_vref ?
- ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
+ { "ads7828", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ads7828_device_ids);
- /* Calculate the LSB resolution */
- ads7828_lsb_resol = (vref_mv*1000)/4096;
+static struct i2c_driver ads7828_driver = {
+ .driver = {
+ .name = "ads7828",
+ },
- return i2c_add_driver(&ads7828_driver);
+ .name = "ads7828",
+ },
-}
Guenter Roeck
Oct 3, 2012, 7:40:02 PM10/3/12
to
On Wed, Oct 03, 2012 at 04:54:07PM -0400, Vivien Didelot wrote:
> As there is no reliable way to identify the chip, it is preferable to
> remove the detect callback, to avoid misdetection.
>
> Module parameters are not worth it here, so let's get rid of them and
> add an ads7828_platform_data structure instead.
>
> Clean the code by removing unused macros, fixing coding style issues,
> avoiding function prototypes and using convenient macros such as
> module_i2c_driver().
>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Applied to -next.
> As there is no reliable way to identify the chip, it is preferable to
> remove the detect callback, to avoid misdetection.
>
> Module parameters are not worth it here, so let's get rid of them and
> add an ads7828_platform_data structure instead.
>
> Clean the code by removing unused macros, fixing coding style issues,
> avoiding function prototypes and using convenient macros such as
> module_i2c_driver().
>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Thanks,
Guenter
Guenter Roeck
Oct 3, 2012, 7:40:03 PM10/3/12
to
On Wed, Oct 03, 2012 at 04:54:08PM -0400, Vivien Didelot wrote:
> From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
>
> The ADS7830 device is almost the same as the ADS7828,
> except that it does 8-bit sampling, instead of 12-bit.
> This patch extends the ads7828 driver to support this chip.
>
> Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
> From: Guillaume Roguez <guillaum...@savoirfairelinux.com>
>
> The ADS7830 device is almost the same as the ADS7828,
> except that it does 8-bit sampling, instead of 12-bit.
> This patch extends the ads7828 driver to support this chip.
>
> Signed-off-by: Guillaume Roguez <guillaum...@savoirfairelinux.com>
> Signed-off-by: Vivien Didelot <vivien....@savoirfairelinux.com>
Applied to -next.
Thanks,
Guenter
Thanks,
Guenter
Guillaume Roguez
Oct 3, 2012, 8:20:02 PM10/3/12
to
Thanks a lot Guenter!
Thanks a lot Vivien also for the help.
Guillaume
----- Mail original -----
De: "Guenter Roeck" <li...@roeck-us.net>
À: "Vivien Didelot" <vivien....@savoirfairelinux.com>
Cc: lm-se...@lm-sensors.org, "Guillaume Roguez" <guillaum...@savoirfairelinux.com>, "Jean Delvare" <kh...@linux-fr.org>, linux-...@vger.kernel.org, "Steve Hardy" <sha...@redhat.com>
Envoyé: Mercredi 3 Octobre 2012 19:37:58
Objet: Re: [PATCH v5 2/2] hwmon: (ads7828) add support for ADS7830
Thanks a lot Vivien also for the help.
Guillaume
----- Mail original -----
De: "Guenter Roeck" <li...@roeck-us.net>
À: "Vivien Didelot" <vivien....@savoirfairelinux.com>
Cc: lm-se...@lm-sensors.org, "Guillaume Roguez" <guillaum...@savoirfairelinux.com>, "Jean Delvare" <kh...@linux-fr.org>, linux-...@vger.kernel.org, "Steve Hardy" <sha...@redhat.com>
Envoyé: Mercredi 3 Octobre 2012 19:37:58
Objet: Re: [PATCH v5 2/2] hwmon: (ads7828) add support for ADS7830
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