[PATCH v3 0/2] iio: adc: Add support for AD7292

2 views
Skip to first unread message

Marcelo Schmitt

unread,
Nov 1, 2019, 12:23:35 PM11/1/19
to ji...@kernel.org, ro...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
This patchset adds a basic driver for the AD7292 ADC/DAC system along
with devicetree binding documentation.

Changelog V3:
- dt-binding: changed spi-cpha property
- dt-binding: added spi-cpha to the list of required properties
- dt-binding: renamed example device node
- dt-binding: added ';' to the final curly braces correctly closing dt-schema
- ad7292: fix up a typo in channel macros

Marcelo Schmitt (2):
dt-bindings: iio: adc: Add dt-schema for AD7292
iio: adc: Add driver support for AD7292

.../bindings/iio/adc/adi,ad7292.yaml | 103 ++++++
MAINTAINERS | 8 +
drivers/iio/adc/Kconfig | 10 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/ad7292.c | 350 ++++++++++++++++++
5 files changed, 472 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
create mode 100644 drivers/iio/adc/ad7292.c

--
2.23.0

Marcelo Schmitt

unread,
Nov 1, 2019, 12:24:04 PM11/1/19
to ji...@kernel.org, ro...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
Add a devicetree schema for AD7292 monitor and control system.

Signed-off-by: Marcelo Schmitt <marcelo....@gmail.com>
---
Changelog V2 -> V3:
- changed spi-cpha property
- added spi-cpha to the list of required properties
- renamed example device node
- added ';' to the final curly braces correctly closing dt-schema

.../bindings/iio/adc/adi,ad7292.yaml | 103 ++++++++++++++++++
MAINTAINERS | 7 ++
2 files changed, 110 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml

diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
new file mode 100644
index 000000000000..1014eb50a263
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
@@ -0,0 +1,103 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/adi,ad7292.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices AD7292 10-Bit Monitor and Control System
+
+maintainers:
+ - Marcelo Schmitt <marcelo....@gmail.com>
+
+description: |
+ Analog Devices AD7292 10-Bit Monitor and Control System with ADC, DACs,
+ Temperature Sensor, and GPIOs
+
+ Specifications about the part can be found at:
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad7292.pdf
+
+properties:
+ compatible:
+ enum:
+ - adi,ad7292
+
+ reg:
+ maxItems: 1
+
+ vref-supply:
+ description: |
+ The regulator supply for ADC and DAC reference voltage.
+
+ spi-cpha: true
+
+ '#address-cells':
+ const: 1
+
+ '#size-cells':
+ const: 0
+
+required:
+ - compatible
+ - reg
+ - spi-cpha
+
+patternProperties:
+ "^channel@[0-7]$":
+ type: object
+ description: |
+ Represents the external channels which are connected to the ADC.
+ See Documentation/devicetree/bindings/iio/adc/adc.txt.
+
+ properties:
+ reg:
+ description: |
+ The channel number. It can have up to 8 channels numbered from 0 to 7.
+ maxItems: 1
+
+ diff-channels:
+ description: see Documentation/devicetree/bindings/iio/adc/adc.txt
+ maxItems: 1
+
+ required:
+ - reg
+
+examples:
+ - |
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ ad7292: adc@0 {
+ compatible = "adi,ad7292";
+ reg = <0>;
+ spi-max-frequency = <25000000>;
+ vref-supply = <&adc_vref>;
+ spi-cpha;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ channel@0 {
+ reg = <0>;
+ diff-channels = <0 1>;
+ };
+ channel@2 {
+ reg = <2>;
+ };
+ channel@3 {
+ reg = <3>;
+ };
+ channel@4 {
+ reg = <4>;
+ };
+ channel@5 {
+ reg = <5>;
+ };
+ channel@6 {
+ reg = <6>;
+ };
+ channel@7 {
+ reg = <7>;
+ };
+ };
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index 32bf5f8116d0..5d00e871c4c6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -813,6 +813,13 @@ S: Supported
F: drivers/iio/adc/ad7124.c
F: Documentation/devicetree/bindings/iio/adc/adi,ad7124.txt

+ANALOG DEVICES INC AD7292 DRIVER
+M: Marcelo Schmitt <marcelo....@gmail.com>
+L: linu...@vger.kernel.org
+W: http://ez.analog.com/community/linux-device-drivers
+S: Supported
+F: Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
+
ANALOG DEVICES INC AD7606 DRIVER
M: Stefan Popa <stefa...@analog.com>
L: linu...@vger.kernel.org
--
2.23.0

Marcelo Schmitt

unread,
Nov 1, 2019, 12:24:31 PM11/1/19
to ji...@kernel.org, ro...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
The AD7292 is a 10-bit monitor and control system with ADC, DACs,
temperature sensor, and GPIOs.

Configure AD7292 devices in direct access mode, enabling single-ended
ADC readings.

Datasheet:
Link: https://www.analog.com/media/en/technical-documentation/data-sheets/ad7292.pdf

Signed-off-by: Marcelo Schmitt <marcelo....@gmail.com>
---
Changelog V2 -> V3:
- fix up a typo in channel macros

MAINTAINERS | 1 +
drivers/iio/adc/Kconfig | 10 ++
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/ad7292.c | 350 +++++++++++++++++++++++++++++++++++++++
4 files changed, 362 insertions(+)
create mode 100644 drivers/iio/adc/ad7292.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 5d00e871c4c6..5941cfc0d6f7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -818,6 +818,7 @@ M: Marcelo Schmitt <marcelo....@gmail.com>
L: linu...@vger.kernel.org
W: http://ez.analog.com/community/linux-device-drivers
S: Supported
+F: drivers/iio/adc/ad7292.c
F: Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml

ANALOG DEVICES INC AD7606 DRIVER
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 632b331429c6..02587c990cb5 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -59,6 +59,16 @@ config AD7291
To compile this driver as a module, choose M here: the
module will be called ad7291.

+config AD7292
+ tristate "Analog Devices AD7292 ADC driver"
+ depends on SPI
+ help
+ Say yes here to build support for Analog Devices AD7292
+ 8 Channel ADC with temperature sensor.
+
+ To compile this driver as a module, choose M here: the
+ module will be called ad7292.
+
config AD7298
tristate "Analog Devices AD7298 ADC driver"
depends on SPI
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 4779ab3ff8fb..1818f2f66566 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_AD7124) += ad7124.o
obj-$(CONFIG_AD7173) += ad7173.o
obj-$(CONFIG_AD7266) += ad7266.o
obj-$(CONFIG_AD7291) += ad7291.o
+obj-$(CONFIG_AD7292) += ad7292.o
obj-$(CONFIG_AD7298) += ad7298.o
obj-$(CONFIG_AD738X) += ad738x.o
obj-$(CONFIG_AD7768) += ad7768-1.o
diff --git a/drivers/iio/adc/ad7292.c b/drivers/iio/adc/ad7292.c
new file mode 100644
index 000000000000..e2badf6ac10d
--- /dev/null
+++ b/drivers/iio/adc/ad7292.c
@@ -0,0 +1,350 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Analog Devices AD7292 SPI ADC driver
+ *
+ * Copyright 2019 Analog Devices Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+
+#include <linux/iio/iio.h>
+
+#define ADI_VENDOR_ID 0x0018
+
+/* AD7292 registers definition */
+#define AD7292_REG_VENDOR_ID 0x00
+#define AD7292_REG_CONF_BANK 0x05
+#define AD7292_REG_CONV_COMM 0x0E
+#define AD7292_REG_ADC_CH(x) (0x10 + (x))
+
+/* AD7292 configuration bank subregisters definition */
+#define AD7292_BANK_REG_VIN_RNG0 0x10
+#define AD7292_BANK_REG_VIN_RNG1 0x11
+#define AD7292_BANK_REG_SAMP_MODE 0x12
+
+#define AD7292_RD_FLAG_MSK(x) (BIT(7) | ((x) & 0x3F))
+
+/* AD7292_REG_ADC_CONVERSION */
+#define AD7292_ADC_DATA_MASK GENMASK(15, 6)
+#define AD7292_ADC_DATA(x) FIELD_GET(AD7292_ADC_DATA_MASK, x)
+
+/* AD7292_CHANNEL_SAMPLING_MODE */
+#define AD7292_CH_SAMP_MODE(reg, ch) ((reg >> 8) & BIT(ch))
+
+/* AD7292_CHANNEL_VIN_RANGE */
+#define AD7292_CH_VIN_RANGE(reg, ch) (reg & BIT(ch))
+
+#define AD7292_VOLTAGE_CHAN(_chan) \
+{ \
+ .type = IIO_VOLTAGE, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .indexed = 1, \
+ .channel = _chan, \
+}
+
+static const struct iio_chan_spec ad7292_channels[] = {
+ AD7292_VOLTAGE_CHAN(0),
+ AD7292_VOLTAGE_CHAN(1),
+ AD7292_VOLTAGE_CHAN(2),
+ AD7292_VOLTAGE_CHAN(3),
+ AD7292_VOLTAGE_CHAN(4),
+ AD7292_VOLTAGE_CHAN(5),
+ AD7292_VOLTAGE_CHAN(6),
+ AD7292_VOLTAGE_CHAN(7)
+};
+
+static const struct iio_chan_spec ad7292_channels_diff[] = {
+ {
+ .type = IIO_VOLTAGE,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .indexed = 1,
+ .differential = 1,
+ .channel = 0,
+ .channel2 = 1,
+ },
+ AD7292_VOLTAGE_CHAN(2),
+ AD7292_VOLTAGE_CHAN(3),
+ AD7292_VOLTAGE_CHAN(4),
+ AD7292_VOLTAGE_CHAN(5),
+ AD7292_VOLTAGE_CHAN(6),
+ AD7292_VOLTAGE_CHAN(7)
+};
+
+struct ad7292_state {
+ struct spi_device *spi;
+ struct regulator *reg;
+ unsigned short vref_mv;
+
+ __be16 d16 ____cacheline_aligned;
+ u8 d8[2];
+};
+
+static int ad7292_spi_reg_read(struct ad7292_state *st, unsigned int addr)
+{
+ int ret;
+
+ st->d8[0] = AD7292_RD_FLAG_MSK(addr);
+
+ ret = spi_write_then_read(st->spi, st->d8, 1, &st->d16, 2);
+ if (ret < 0)
+ return ret;
+
+ return be16_to_cpu(st->d16);
+}
+
+static int ad7292_spi_subreg_read(struct ad7292_state *st, unsigned int addr,
+ unsigned int sub_addr, unsigned int len)
+{
+ unsigned int shift = 16 - (8 * len);
+ int ret;
+
+ st->d8[0] = AD7292_RD_FLAG_MSK(addr);
+ st->d8[1] = sub_addr;
+
+ ret = spi_write_then_read(st->spi, st->d8, 2, &st->d16, len);
+ if (ret < 0)
+ return ret;
+
+ return (be16_to_cpu(st->d16) >> shift);
+}
+
+static int ad7292_single_conversion(struct ad7292_state *st,
+ unsigned int chan_addr)
+{
+ int ret;
+
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = &st->d8,
+ .len = 4,
+ .delay_usecs = 6,
+ }, {
+ .rx_buf = &st->d16,
+ .len = 2,
+ },
+ };
+
+ st->d8[0] = chan_addr;
+ st->d8[1] = AD7292_RD_FLAG_MSK(AD7292_REG_CONV_COMM);
+
+ ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
+
+ if (ret < 0)
+ return ret;
+
+ return be16_to_cpu(st->d16);
+}
+
+static int ad7292_vin_range_multiplier(struct ad7292_state *st, int channel)
+{
+ int samp_mode, range0, range1, factor = 1;
+
+ /*
+ * Every AD7292 ADC channel may have its input range adjusted according
+ * to the settings at the ADC sampling mode and VIN range subregisters.
+ * For a given channel, the minimum input range is equal to Vref, and it
+ * may be increased by a multiplier factor of 2 or 4 according to the
+ * following rule:
+ * If channel is being sampled with respect to AGND:
+ * factor = 4 if VIN range0 and VIN range1 equal 0
+ * factor = 2 if only one of VIN ranges equal 1
+ * factor = 1 if both VIN range0 and VIN range1 equal 1
+ * If channel is being sampled with respect to AVDD:
+ * factor = 4 if VIN range0 and VIN range1 equal 0
+ * Behavior is undefined if any of VIN range doesn't equal 0
+ */
+
+ samp_mode = ad7292_spi_subreg_read(st, AD7292_REG_CONF_BANK,
+ AD7292_BANK_REG_SAMP_MODE, 2);
+
+ if (samp_mode < 0)
+ return samp_mode;
+
+ range0 = ad7292_spi_subreg_read(st, AD7292_REG_CONF_BANK,
+ AD7292_BANK_REG_VIN_RNG0, 2);
+
+ if (range0 < 0)
+ return range0;
+
+ range1 = ad7292_spi_subreg_read(st, AD7292_REG_CONF_BANK,
+ AD7292_BANK_REG_VIN_RNG1, 2);
+
+ if (range1 < 0)
+ return range1;
+
+ if (AD7292_CH_SAMP_MODE(samp_mode, channel)) {
+ /* Sampling with respect to AGND */
+ if (!AD7292_CH_VIN_RANGE(range0, channel))
+ factor *= 2;
+
+ if (!AD7292_CH_VIN_RANGE(range1, channel))
+ factor *= 2;
+
+ } else {
+ /* Sampling with respect to AVDD */
+ if (AD7292_CH_VIN_RANGE(range0, channel) ||
+ AD7292_CH_VIN_RANGE(range1, channel))
+ return -EPERM;
+
+ factor = 4;
+ }
+
+ return factor;
+}
+
+static int ad7292_read_raw(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ int *val, int *val2, long info)
+{
+ struct ad7292_state *st = iio_priv(indio_dev);
+ unsigned int ch_addr;
+ int ret;
+
+ switch (info) {
+ case IIO_CHAN_INFO_RAW:
+ ch_addr = AD7292_REG_ADC_CH(chan->channel);
+ ret = ad7292_single_conversion(st, ch_addr);
+ if (ret < 0)
+ return ret;
+
+ *val = AD7292_ADC_DATA(ret);
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ /*
+ * To convert a raw value to standard units, the IIO defines
+ * this formula: Scaled value = (raw + offset) * scale.
+ * For the scale to be a correct multiplier for (raw + offset),
+ * it must be calculated as the input range divided by the
+ * number of possible distinct input values. Given the ADC data
+ * is 10 bit long, it may assume 2^10 distinct values.
+ * Hence, scale = range / 2^10. The IIO_VAL_FRACTIONAL_LOG2
+ * return type indicates to the IIO API to divide *val by 2 to
+ * the power of *val2 when returning from read_raw.
+ */
+
+ ret = ad7292_vin_range_multiplier(st, chan->channel);
+ if (ret < 0)
+ return ret;
+
+ *val = st->vref_mv * ret;
+ *val2 = 10;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ default:
+ break;
+ }
+ return -EINVAL;
+}
+
+static const struct iio_info ad7292_info = {
+ .read_raw = ad7292_read_raw,
+};
+
+static void ad7292_regulator_disable(void *data)
+{
+ struct ad7292_state *st = data;
+
+ regulator_disable(st->reg);
+}
+
+static int ad7292_probe(struct spi_device *spi)
+{
+ struct ad7292_state *st;
+ struct iio_dev *indio_dev;
+ struct device_node *child;
+ bool diff_channels = 0;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+ st->spi = spi;
+
+ ret = ad7292_spi_reg_read(st, AD7292_REG_VENDOR_ID);
+ if (ret != ADI_VENDOR_ID) {
+ dev_err(&spi->dev, "Wrong vendor id 0x%x\n", ret);
+ return -EINVAL;
+ }
+
+ spi_set_drvdata(spi, indio_dev);
+
+ st->reg = devm_regulator_get_optional(&spi->dev, "vref");
+ if (!IS_ERR(st->reg)) {
+ ret = regulator_enable(st->reg);
+ if (ret) {
+ dev_err(&spi->dev,
+ "Failed to enable external vref supply\n");
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(&spi->dev,
+ ad7292_regulator_disable, st);
+ if (ret) {
+ regulator_disable(st->reg);
+ return ret;
+ }
+
+ ret = regulator_get_voltage(st->reg);
+ if (ret < 0)
+ return ret;
+
+ st->vref_mv = ret / 1000;
+ } else {
+ /* Use the internal voltage reference. */
+ st->vref_mv = 1250;
+ }
+
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = spi_get_device_id(spi)->name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->info = &ad7292_info;
+
+ for_each_available_child_of_node(spi->dev.of_node, child) {
+ diff_channels = of_property_read_bool(child, "diff-channels");
+ if (diff_channels)
+ break;
+ }
+
+ if (diff_channels) {
+ indio_dev->num_channels = ARRAY_SIZE(ad7292_channels_diff);
+ indio_dev->channels = ad7292_channels_diff;
+ } else {
+ indio_dev->num_channels = ARRAY_SIZE(ad7292_channels);
+ indio_dev->channels = ad7292_channels;
+ }
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct spi_device_id ad7292_id_table[] = {
+ { "ad7292", 0 },
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad7292_id_table);
+
+static const struct of_device_id ad7292_of_match[] = {
+ { .compatible = "adi,ad7292" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ad7292_of_match);
+
+static struct spi_driver ad7292_driver = {
+ .driver = {
+ .name = "ad7292",
+ .of_match_table = ad7292_of_match,
+ },
+ .probe = ad7292_probe,
+ .id_table = ad7292_id_table,
+};
+module_spi_driver(ad7292_driver);
+
+MODULE_AUTHOR("Marcelo Schmitt <marcelo....@gmail.com>");
+MODULE_DESCRIPTION("Analog Devices AD7292 ADC driver");
+MODULE_LICENSE("GPL v2");
--
2.23.0

Jonathan Cameron

unread,
Nov 3, 2019, 6:52:11 AM11/3/19
to Marcelo Schmitt, ro...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
On Fri, 1 Nov 2019 13:24:26 -0300
Marcelo Schmitt <marcelo....@gmail.com> wrote:

> The AD7292 is a 10-bit monitor and control system with ADC, DACs,
> temperature sensor, and GPIOs.
>
> Configure AD7292 devices in direct access mode, enabling single-ended
> ADC readings.
>
> Datasheet:
> Link: https://www.analog.com/media/en/technical-documentation/data-sheets/ad7292.pdf
>
> Signed-off-by: Marcelo Schmitt <marcelo....@gmail.com>
One totally trivial thing inline if you happen to be respinning.
Otherwise I'll fix up when applying.

I would like to give a bit of time for others to comment, particularly on the dt
bindings as I frequently miss problems in them. Hence I won't be applying it today
but may pick it up later in the week or next weekend.

Thanks,

Jonathan
Trivial but all macro parameters should be in brackets to prevent
weirdness if some sticks a parameter with higher precedence in there
so ((reg) & BIT(ch)).

I can fix this up if the rest is fine.

Rob Herring

unread,
Nov 5, 2019, 4:09:32 PM11/5/19
to Marcelo Schmitt, ji...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
On Fri, Nov 01, 2019 at 01:23:59PM -0300, Marcelo Schmitt wrote:
> Add a devicetree schema for AD7292 monitor and control system.
>
> Signed-off-by: Marcelo Schmitt <marcelo....@gmail.com>
> ---
> Changelog V2 -> V3:
> - changed spi-cpha property
> - added spi-cpha to the list of required properties
> - renamed example device node
> - added ';' to the final curly braces correctly closing dt-schema
>
> .../bindings/iio/adc/adi,ad7292.yaml | 103 ++++++++++++++++++
> MAINTAINERS | 7 ++
> 2 files changed, 110 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
> new file mode 100644
> index 000000000000..1014eb50a263
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
> @@ -0,0 +1,103 @@
> +# SPDX-License-Identifier: GPL-2.0

For new bindings:

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
Can be a constraint:

items:
- maximum: 7

> + maxItems: 1

And then drop this because it's implied by the above.

Marcelo Schmitt

unread,
Nov 7, 2019, 11:38:34 AM11/7/19
to Jonathan Cameron, ro...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
Hi,

I'll respin for the dt-schema. Thus, I can add brackets to macro
parameters. I think I found another couple of brackets missing.
Comments inline.

Thanks,

Marcelo
Maybe this one would also need to be changed for the same reason:
(((reg) >> 8) & BIT(ch)).

> > +
> > +/* AD7292_CHANNEL_VIN_RANGE */
> > +#define AD7292_CH_VIN_RANGE(reg, ch) (reg & BIT(ch))
>
> Trivial but all macro parameters should be in brackets to prevent
> weirdness if some sticks a parameter with higher precedence in there
> so ((reg) & BIT(ch)).
>
> I can fix this up if the rest is fine.

Since I'll be respinning, I can add the brackets.

Marcelo Schmitt

unread,
Nov 8, 2019, 8:55:34 AM11/8/19
to ji...@kernel.org, ro...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
This patchset adds a basic driver for the AD7292 ADC/DAC system along
with devicetree binding documentation.

Changelog V4:
- dt-binding: updated SPDX identifier to GPL-2.0-only
- dt-binding: changed maxitems constraint on channel property
- ad7292: added brackets to shield macro parameters

Marcelo Schmitt (2):
dt-bindings: iio: adc: Add dt-schema for AD7292
iio: adc: Add driver support for AD7292

.../bindings/iio/adc/adi,ad7292.yaml | 104 ++++++
MAINTAINERS | 8 +
drivers/iio/adc/Kconfig | 10 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/ad7292.c | 350 ++++++++++++++++++
5 files changed, 473 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml

Marcelo Schmitt

unread,
Nov 8, 2019, 8:56:15 AM11/8/19
to ji...@kernel.org, ro...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
Add a devicetree schema for AD7292 monitor and control system.

Signed-off-by: Marcelo Schmitt <marcelo....@gmail.com>
---
Changelog V3 -> V4:
- updated SPDX identifier to GPL-2.0-only
- changed maxitems constraint on channel property

.../bindings/iio/adc/adi,ad7292.yaml | 104 ++++++++++++++++++
MAINTAINERS | 7 ++
2 files changed, 111 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml

diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
new file mode 100644
index 000000000000..b68be3aaf587
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
@@ -0,0 +1,104 @@
+# SPDX-License-Identifier: GPL-2.0-only
+ items:
+ maximum: 7
diff --git a/MAINTAINERS b/MAINTAINERS
index 32bf5f8116d0..5d00e871c4c6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -813,6 +813,13 @@ S: Supported
F: drivers/iio/adc/ad7124.c
F: Documentation/devicetree/bindings/iio/adc/adi,ad7124.txt

+ANALOG DEVICES INC AD7292 DRIVER
+M: Marcelo Schmitt <marcelo....@gmail.com>
+L: linu...@vger.kernel.org
+W: http://ez.analog.com/community/linux-device-drivers
+S: Supported
+F: Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
+
ANALOG DEVICES INC AD7606 DRIVER

Marcelo Schmitt

unread,
Nov 8, 2019, 8:56:57 AM11/8/19
to ji...@kernel.org, ro...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
The AD7292 is a 10-bit monitor and control system with ADC, DACs,
temperature sensor, and GPIOs.

Configure AD7292 devices in direct access mode, enabling single-ended
ADC readings.

Datasheet:
Link: https://www.analog.com/media/en/technical-documentation/data-sheets/ad7292.pdf

Signed-off-by: Marcelo Schmitt <marcelo....@gmail.com>
---
Changelog V3 -> V4:
- added brackets to shield macro parameters

MAINTAINERS | 1 +
drivers/iio/adc/Kconfig | 10 ++
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/ad7292.c | 350 +++++++++++++++++++++++++++++++++++++++
4 files changed, 362 insertions(+)
create mode 100644 drivers/iio/adc/ad7292.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 5d00e871c4c6..5941cfc0d6f7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -818,6 +818,7 @@ M: Marcelo Schmitt <marcelo....@gmail.com>
L: linu...@vger.kernel.org
W: http://ez.analog.com/community/linux-device-drivers
S: Supported
+F: drivers/iio/adc/ad7292.c
F: Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml

ANALOG DEVICES INC AD7606 DRIVER
new file mode 100644
index 000000000000..a6798f7dfdb8
+#define AD7292_CH_SAMP_MODE(reg, ch) (((reg) >> 8) & BIT(ch))
+
+/* AD7292_CHANNEL_VIN_RANGE */
+#define AD7292_CH_VIN_RANGE(reg, ch) ((reg) & BIT(ch))
--
2.23.0

Jonathan Cameron

unread,
Nov 10, 2019, 11:07:29 AM11/10/19
to Marcelo Schmitt, ro...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
On Fri, 8 Nov 2019 10:56:09 -0300
Marcelo Schmitt <marcelo....@gmail.com> wrote:

> Add a devicetree schema for AD7292 monitor and control system.
>
> Signed-off-by: Marcelo Schmitt <marcelo....@gmail.com>
Seems like you have addressed everything Rob raised, so I'll apply this
and it can go out for build testing. Still some time for Rob to add
a tag if he wants to!

Thanks,

Jonathan

Jonathan Cameron

unread,
Nov 10, 2019, 11:08:10 AM11/10/19
to Marcelo Schmitt, ro...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
On Fri, 8 Nov 2019 10:56:50 -0300
Marcelo Schmitt <marcelo....@gmail.com> wrote:

> The AD7292 is a 10-bit monitor and control system with ADC, DACs,
> temperature sensor, and GPIOs.
>
> Configure AD7292 devices in direct access mode, enabling single-ended
> ADC readings.
>
> Datasheet:
> Link: https://www.analog.com/media/en/technical-documentation/data-sheets/ad7292.pdf
>
> Signed-off-by: Marcelo Schmitt <marcelo....@gmail.com>
Looks good to me.

Applied to the togreg branch of iio.git and pushed out as testing for the
autobuilders to play with it.

Thanks,

Jonathan

Rob Herring

unread,
Nov 12, 2019, 2:39:44 PM11/12/19
to Marcelo Schmitt, ji...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
On Fri, Nov 08, 2019 at 10:56:09AM -0300, Marcelo Schmitt wrote:
> Add a devicetree schema for AD7292 monitor and control system.
>
> Signed-off-by: Marcelo Schmitt <marcelo....@gmail.com>
> ---
> Changelog V3 -> V4:
> - updated SPDX identifier to GPL-2.0-only
> - changed maxitems constraint on channel property
>
> .../bindings/iio/adc/adi,ad7292.yaml | 104 ++++++++++++++++++
> MAINTAINERS | 7 ++
> 2 files changed, 111 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
> new file mode 100644
> index 000000000000..b68be3aaf587
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
> @@ -0,0 +1,104 @@
> +# SPDX-License-Identifier: GPL-2.0-only

Sigh, I gave you the exact line to use:

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)

I've said to dual license with (GPL-2.0-only OR BSD-2-Clause) and people
think I mean to pick one. So now I just give the whole line. I don't
know how to be clearer.
Not what I said either. A slight but important difference in that you
are missing a '-' to make 'items' a list rather than a schema/dict.

Update dt-schema. This should give a warning now.

Marcelo Schmitt

unread,
Nov 13, 2019, 9:52:06 AM11/13/19
to Rob Herring, ji...@kernel.org, dragos...@analog.com, alexandru...@analog.com, linux-...@vger.kernel.org, linu...@vger.kernel.org, devic...@vger.kernel.org, kerne...@googlegroups.com
Hi Rob,

Thanks for reviewing the binding doc again.
Aparently, this patch was added to Greg KH's staging tree.
What is the right procedure in this case? Should I send a v5 patchset or
just send a patch for this doc?

In any case, I still have some doubts about the maximum constraint of
the channel property. Comments inline.


Thanks

Marcelo

On 11/12, Rob Herring wrote:
> On Fri, Nov 08, 2019 at 10:56:09AM -0300, Marcelo Schmitt wrote:
> > Add a devicetree schema for AD7292 monitor and control system.
> >
> > Signed-off-by: Marcelo Schmitt <marcelo....@gmail.com>
> > ---
> > Changelog V3 -> V4:
> > - updated SPDX identifier to GPL-2.0-only
> > - changed maxitems constraint on channel property
> >
> > .../bindings/iio/adc/adi,ad7292.yaml | 104 ++++++++++++++++++
> > MAINTAINERS | 7 ++
> > 2 files changed, 111 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
> > new file mode 100644
> > index 000000000000..b68be3aaf587
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7292.yaml
> > @@ -0,0 +1,104 @@
> > +# SPDX-License-Identifier: GPL-2.0-only
>
> Sigh, I gave you the exact line to use:
>
> # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>
> I've said to dual license with (GPL-2.0-only OR BSD-2-Clause) and people
> think I mean to pick one. So now I just give the whole line. I don't
> know how to be clearer.

I thought I could use just GPL-2.0 since the driver code is GPL-2.0.
Anyway, I'll use the above line to specify the dt-binding license.
I'm confused, I don't know how to make this doc the way you want.
I pulled the updates from the master branch of dt-schema repo and
reinstalled it.
Then I tried
items:
- maximum: 7
I've tried
- items:
maximum: 7
I also tried
- items:
maximum: 7
all gave me parsing errors when processing the ad7292 schema with
'make dt_binding_check' and also with 'make -k dt_binding_check'.
Am I using the right branch? Should I pull from a branch other than the
master?
I was first inspired by the adi,ad7124.yaml doc which has a similar
channel declaration. Curiously, processing the ad7292 schema the way it
was in v4 gave me no errors so, I must be missing something.

Rob Herring

unread,
Nov 13, 2019, 12:06:59 PM11/13/19
to Marcelo Schmitt, Jonathan Cameron, Dragos Bogdan, Alexandru Ardelean, linux-...@vger.kernel.org, open list:IIO SUBSYSTEM AND DRIVERS, devic...@vger.kernel.org, kerne...@googlegroups.com
On Wed, Nov 13, 2019 at 8:52 AM Marcelo Schmitt
<marcelo....@gmail.com> wrote:
>
> Hi Rob,
>
> Thanks for reviewing the binding doc again.
> Aparently, this patch was added to Greg KH's staging tree.
> What is the right procedure in this case? Should I send a v5 patchset or
> just send a patch for this doc?

You need to do an incremental patch. Greg doesn't rebase.
Sorry, my fault there. The meta-schema requires 'minimum' if you give
'maximum'. So:

items:
- minimum: 0
maximum: 7

The error message was less than useful, but I think I have a fix for that too.

Rob

Jonathan Cameron

unread,
Nov 16, 2019, 10:22:56 AM11/16/19
to Rob Herring, Marcelo Schmitt, Dragos Bogdan, Alexandru Ardelean, linux-...@vger.kernel.org, open list:IIO SUBSYSTEM AND DRIVERS, devic...@vger.kernel.org, kerne...@googlegroups.com
On Wed, 13 Nov 2019 11:06:45 -0600
Rob Herring <ro...@kernel.org> wrote:

> On Wed, Nov 13, 2019 at 8:52 AM Marcelo Schmitt
> <marcelo....@gmail.com> wrote:
> >
> > Hi Rob,
> >
> > Thanks for reviewing the binding doc again.
> > Aparently, this patch was added to Greg KH's staging tree.
> > What is the right procedure in this case? Should I send a v5 patchset or
> > just send a patch for this doc?
>
> You need to do an incremental patch. Greg doesn't rebase.
Sorry. I jumped the gun a bit here. Send me an incremental patch and
we'll get it queued up. As it can be considered 'a license fix'
we can get it lined up for straight after the merge window.

Thanks,

Jonathan
Reply all
Reply to author
Forward
0 new messages