[PATCH] Add smbus support back in

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adu...@google.com

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Nov 20, 2008, 12:40:12 PM11/20/08
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Add SMBus support back into iotools.

- Added linux-i2c-dev.h which is a copy of i2c-dev.h from the Linux source.
- Updated Makefile to include smbus_rw.c in the build.
- Fixed issue where i2c_smbus_write_byte_data was being called for a 16-bit
operation.

diff --git a/Makefile b/Makefile
index 8b18891..8209fd4 100644
--- a/Makefile
+++ b/Makefile
@@ -39,10 +39,7 @@ SBINDIR ?= /usr/local/sbin

BINARY=iotools
OBJS_TO_BUILD=$(filter-out iotools.o, $(patsubst %.c,%.o,$(wildcard *.c)))
-#OBJS=$(OBJS_TO_BUILD)
-# temp workaround to not build smbus_rw because of issue:
-# http://code.google.com/p/iotools/issues/detail?id=1
-OBJS=$(filter-out smbus_rw.o, $(OBJS_TO_BUILD))
+OBJS=$(OBJS_TO_BUILD)

all: $(BINARY)

diff --git a/linux-i2c-dev.h b/linux-i2c-dev.h
new file mode 100644
index 0000000..5580a2f
--- /dev/null
+++ b/linux-i2c-dev.h
@@ -0,0 +1,363 @@
+/*
+ i2c-dev.h - i2c-bus driver, char device interface
+
+ Copyright (C) 1995-97 Simon G. Vogl
+ Copyright (C) 1998-99 Frodo Looijaard <fro...@dds.nl>
+
+ 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
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+
+#ifndef LIB_I2CDEV_H
+#define LIB_I2CDEV_H
+
+#include <linux/types.h>
+#include <sys/ioctl.h>
+
+#if defined(__STRICT_ANSI__) || !defined(__GNUC__)
+#define inline
+#endif
+
+/* -- i2c.h -- */
+
+
+/*
+ * I2C Message - used for pure i2c transaction, also from /dev interface
+ */
+struct i2c_msg {
+ __u16 addr; /* slave address */
+ unsigned short flags;
+#define I2C_M_TEN 0x10 /* we have a ten bit chip address */
+#define I2C_M_RD 0x01
+#define I2C_M_NOSTART 0x4000
+#define I2C_M_REV_DIR_ADDR 0x2000
+#define I2C_M_IGNORE_NAK 0x1000
+#define I2C_M_NO_RD_ACK 0x0800
+ short len; /* msg length */
+ char *buf; /* pointer to msg data */
+ int err;
+ short done;
+};
+
+/* To determine what functionality is present */
+
+#define I2C_FUNC_I2C 0x00000001
+#define I2C_FUNC_10BIT_ADDR 0x00000002
+#define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_{REV_DIR_ADDR,NOSTART,..} */
+#define I2C_FUNC_SMBUS_HWPEC_CALC 0x00000008 /* SMBus 2.0 */
+#define I2C_FUNC_SMBUS_READ_WORD_DATA_PEC 0x00000800 /* SMBus 2.0 */
+#define I2C_FUNC_SMBUS_WRITE_WORD_DATA_PEC 0x00001000 /* SMBus 2.0 */
+#define I2C_FUNC_SMBUS_PROC_CALL_PEC 0x00002000 /* SMBus 2.0 */
+#define I2C_FUNC_SMBUS_BLOCK_PROC_CALL_PEC 0x00004000 /* SMBus 2.0 */
+#define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
+#define I2C_FUNC_SMBUS_QUICK 0x00010000
+#define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
+#define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
+#define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
+#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
+#define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
+#define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
+#define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
+#define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
+#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
+#define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */
+#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */
+#define I2C_FUNC_SMBUS_READ_I2C_BLOCK_2 0x10000000 /* I2C-like block xfer */
+#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK_2 0x20000000 /* w/ 2-byte reg. addr. */
+#define I2C_FUNC_SMBUS_READ_BLOCK_DATA_PEC 0x40000000 /* SMBus 2.0 */
+#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA_PEC 0x80000000 /* SMBus 2.0 */
+
+#define I2C_FUNC_SMBUS_BYTE I2C_FUNC_SMBUS_READ_BYTE | \
+ I2C_FUNC_SMBUS_WRITE_BYTE
+#define I2C_FUNC_SMBUS_BYTE_DATA I2C_FUNC_SMBUS_READ_BYTE_DATA | \
+ I2C_FUNC_SMBUS_WRITE_BYTE_DATA
+#define I2C_FUNC_SMBUS_WORD_DATA I2C_FUNC_SMBUS_READ_WORD_DATA | \
+ I2C_FUNC_SMBUS_WRITE_WORD_DATA
+#define I2C_FUNC_SMBUS_BLOCK_DATA I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
+ I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
+#define I2C_FUNC_SMBUS_I2C_BLOCK I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
+ I2C_FUNC_SMBUS_WRITE_I2C_BLOCK
+#define I2C_FUNC_SMBUS_I2C_BLOCK_2 I2C_FUNC_SMBUS_READ_I2C_BLOCK_2 | \
+ I2C_FUNC_SMBUS_WRITE_I2C_BLOCK_2
+#define I2C_FUNC_SMBUS_BLOCK_DATA_PEC I2C_FUNC_SMBUS_READ_BLOCK_DATA_PEC | \
+ I2C_FUNC_SMBUS_WRITE_BLOCK_DATA_PEC
+#define I2C_FUNC_SMBUS_WORD_DATA_PEC I2C_FUNC_SMBUS_READ_WORD_DATA_PEC | \
+ I2C_FUNC_SMBUS_WRITE_WORD_DATA_PEC
+
+#define I2C_FUNC_SMBUS_READ_BYTE_PEC I2C_FUNC_SMBUS_READ_BYTE_DATA
+#define I2C_FUNC_SMBUS_WRITE_BYTE_PEC I2C_FUNC_SMBUS_WRITE_BYTE_DATA
+#define I2C_FUNC_SMBUS_READ_BYTE_DATA_PEC I2C_FUNC_SMBUS_READ_WORD_DATA
+#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA_PEC I2C_FUNC_SMBUS_WRITE_WORD_DATA
+#define I2C_FUNC_SMBUS_BYTE_PEC I2C_FUNC_SMBUS_BYTE_DATA
+#define I2C_FUNC_SMBUS_BYTE_DATA_PEC I2C_FUNC_SMBUS_WORD_DATA
+
+#define I2C_FUNC_SMBUS_EMUL I2C_FUNC_SMBUS_QUICK | \
+ I2C_FUNC_SMBUS_BYTE | \
+ I2C_FUNC_SMBUS_BYTE_DATA | \
+ I2C_FUNC_SMBUS_WORD_DATA | \
+ I2C_FUNC_SMBUS_PROC_CALL | \
+ I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
+ I2C_FUNC_SMBUS_WRITE_BLOCK_DATA_PEC | \
+ I2C_FUNC_SMBUS_I2C_BLOCK
+
+/*
+ * Data for SMBus Messages
+ */
+#define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
+#define I2C_SMBUS_I2C_BLOCK_MAX 32 /* Not specified but we use same structure */
+union i2c_smbus_data {
+ __u8 byte;
+ __u16 word;
+ __u8 block[I2C_SMBUS_BLOCK_MAX + 3]; /* block[0] is used for length */
+ /* one more for read length in block process call */
+ /* and one more for PEC */
+};
+
+/* smbus_access read or write markers */
+#define I2C_SMBUS_READ 1
+#define I2C_SMBUS_WRITE 0
+
+/* SMBus transaction types (size parameter in the above functions)
+ Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
+#define I2C_SMBUS_QUICK 0
+#define I2C_SMBUS_BYTE 1
+#define I2C_SMBUS_BYTE_DATA 2
+#define I2C_SMBUS_WORD_DATA 3
+#define I2C_SMBUS_PROC_CALL 4
+#define I2C_SMBUS_BLOCK_DATA 5
+#define I2C_SMBUS_I2C_BLOCK_DATA 6
+#define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */
+#define I2C_SMBUS_BLOCK_DATA_PEC 8 /* SMBus 2.0 */
+#define I2C_SMBUS_PROC_CALL_PEC 9 /* SMBus 2.0 */
+#define I2C_SMBUS_BLOCK_PROC_CALL_PEC 10 /* SMBus 2.0 */
+#define I2C_SMBUS_WORD_DATA_PEC 11 /* SMBus 2.0 */
+
+
+/* ----- commands for the ioctl like i2c_command call:
+ * note that additional calls are defined in the algorithm and hw
+ * dependent layers - these can be listed here, or see the
+ * corresponding header files.
+ */
+ /* -> bit-adapter specific ioctls */
+#define I2C_RETRIES 0x0701 /* number of times a device address */
+ /* should be polled when not */
+ /* acknowledging */
+#define I2C_TIMEOUT 0x0702 /* set timeout - call with int */
+
+
+/* this is for i2c-dev.c */
+#define I2C_SLAVE 0x0703 /* Change slave address */
+ /* Attn.: Slave address is 7 or 10 bits */
+#define I2C_SLAVE_FORCE 0x0706 /* Change slave address */
+ /* Attn.: Slave address is 7 or 10 bits */
+ /* This changes the address, even if it */
+ /* is already taken! */
+#define I2C_TENBIT 0x0704 /* 0 for 7 bit addrs, != 0 for 10 bit */
+
+#define I2C_FUNCS 0x0705 /* Get the adapter functionality */
+#define I2C_RDWR 0x0707 /* Combined R/W transfer (one stop only)*/
+#define I2C_PEC 0x0708 /* != 0 for SMBus PEC */
+#if 0
+#define I2C_ACK_TEST 0x0710 /* See if a slave is at a specific address */
+#endif
+
+#define I2C_SMBUS 0x0720 /* SMBus-level access */
+
+/* -- i2c.h -- */
+
+
+/* Note: 10-bit addresses are NOT supported! */
+
+/* This is the structure as used in the I2C_SMBUS ioctl call */
+struct i2c_smbus_ioctl_data {
+ char read_write;
+ __u8 command;
+ int size;
+ union i2c_smbus_data *data;
+};
+
+/* This is the structure as used in the I2C_RDWR ioctl call */
+struct i2c_rdwr_ioctl_data {
+ struct i2c_msg *msgs; /* pointers to i2c_msgs */
+ int nmsgs; /* number of i2c_msgs */
+};
+
+
+static inline __s32 i2c_smbus_access(int file, char read_write, __u8 command,
+ int size, union i2c_smbus_data *data)
+{
+ struct i2c_smbus_ioctl_data args;
+
+ args.read_write = read_write;
+ args.command = command;
+ args.size = size;
+ args.data = data;
+ return ioctl(file,I2C_SMBUS,&args);
+}
+
+
+static inline __s32 i2c_smbus_write_quick(int file, __u8 value)
+{
+ return i2c_smbus_access(file,value,0,I2C_SMBUS_QUICK,NULL);
+}
+
+static inline __s32 i2c_smbus_read_byte(int file)
+{
+ union i2c_smbus_data data;
+ if (i2c_smbus_access(file,I2C_SMBUS_READ,0,I2C_SMBUS_BYTE,&data))
+ return -1;
+ else
+ return 0x0FF & data.byte;
+}
+
+static inline __s32 i2c_smbus_write_byte(int file, __u8 value)
+{
+ return i2c_smbus_access(file,I2C_SMBUS_WRITE,value,
+ I2C_SMBUS_BYTE,NULL);
+}
+
+static inline __s32 i2c_smbus_read_byte_data(int file, __u8 command)
+{
+ union i2c_smbus_data data;
+ if (i2c_smbus_access(file,I2C_SMBUS_READ,command,
+ I2C_SMBUS_BYTE_DATA,&data))
+ return -1;
+ else
+ return 0x0FF & data.byte;
+}
+
+static inline __s32 i2c_smbus_write_byte_data(int file, __u8 command,
+ __u8 value)
+{
+ union i2c_smbus_data data;
+ data.byte = value;
+ return i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
+ I2C_SMBUS_BYTE_DATA, &data);
+}
+
+static inline __s32 i2c_smbus_read_word_data(int file, __u8 command)
+{
+ union i2c_smbus_data data;
+ if (i2c_smbus_access(file,I2C_SMBUS_READ,command,
+ I2C_SMBUS_WORD_DATA,&data))
+ return -1;
+ else
+ return 0x0FFFF & data.word;
+}
+
+static inline __s32 i2c_smbus_write_word_data(int file, __u8 command,
+ __u16 value)
+{
+ union i2c_smbus_data data;
+ data.word = value;
+ return i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
+ I2C_SMBUS_WORD_DATA, &data);
+}
+
+static inline __s32 i2c_smbus_process_call(int file, __u8 command, __u16 value)
+{
+ union i2c_smbus_data data;
+ data.word = value;
+ if (i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
+ I2C_SMBUS_PROC_CALL,&data))
+ return -1;
+ else
+ return 0x0FFFF & data.word;
+}
+
+
+/* Returns the number of read bytes */
+static inline __s32 i2c_smbus_read_block_data(int file, __u8 command,
+ __u8 *values)
+{
+ union i2c_smbus_data data;
+ int i;
+ if (i2c_smbus_access(file,I2C_SMBUS_READ,command,
+ I2C_SMBUS_BLOCK_DATA,&data))
+ return -1;
+ else {
+ for (i = 1; i <= data.block[0]; i++)
+ values[i-1] = data.block[i];
+ return data.block[0];
+ }
+}
+
+static inline __s32 i2c_smbus_write_block_data(int file, __u8 command,
+ __u8 length, __u8 *values)
+{
+ union i2c_smbus_data data;
+ int i;
+ if (length > 32)
+ length = 32;
+ for (i = 1; i <= length; i++)
+ data.block[i] = values[i-1];
+ data.block[0] = length;
+ return i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
+ I2C_SMBUS_BLOCK_DATA, &data);
+}
+
+/* Returns the number of read bytes */
+static inline __s32 i2c_smbus_read_i2c_block_data(int file, __u8 command,
+ __u8 *values)
+{
+ union i2c_smbus_data data;
+ int i;
+ if (i2c_smbus_access(file,I2C_SMBUS_READ,command,
+ I2C_SMBUS_I2C_BLOCK_DATA,&data))
+ return -1;
+ else {
+ for (i = 1; i <= data.block[0]; i++)
+ values[i-1] = data.block[i];
+ return data.block[0];
+ }
+}
+
+static inline __s32 i2c_smbus_write_i2c_block_data(int file, __u8 command,
+ __u8 length, __u8 *values)
+{
+ union i2c_smbus_data data;
+ int i;
+ if (length > 32)
+ length = 32;
+ for (i = 1; i <= length; i++)
+ data.block[i] = values[i-1];
+ data.block[0] = length;
+ return i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
+ I2C_SMBUS_I2C_BLOCK_DATA, &data);
+}
+
+/* Returns the number of read bytes */
+static inline __s32 i2c_smbus_block_process_call(int file, __u8 command,
+ __u8 length, __u8 *values)
+{
+ union i2c_smbus_data data;
+ int i;
+ if (length > 32)
+ length = 32;
+ for (i = 1; i <= length; i++)
+ data.block[i] = values[i-1];
+ data.block[0] = length;
+ if (i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
+ I2C_SMBUS_BLOCK_PROC_CALL,&data))
+ return -1;
+ else {
+ for (i = 1; i <= data.block[0]; i++)
+ values[i-1] = data.block[i];
+ return data.block[0];
+ }
+}
+
+
+#endif /* LIB_I2CDEV_H */
diff --git a/smbus_rw.c b/smbus_rw.c
index 46f3a77..2f87f2a 100644
--- a/smbus_rw.c
+++ b/smbus_rw.c
@@ -26,7 +26,7 @@
#include <unistd.h>
#include <sys/ioctl.h>
#include "commands.h"
-#include <linux/i2c-dev.h>
+#include "linux-i2c-dev.h"

enum SMBUS_SIZE
{
@@ -288,7 +288,7 @@ smbus_write_op(struct smbus_op_params *params, const struct smbus_op *op)
params->data.fixed.u8);
break;
case SMBUS_SIZE_16:
- result = i2c_smbus_write_byte_data(params->fd, params->reg,
+ result = i2c_smbus_write_word_data(params->fd, params->reg,
params->data.fixed.u16);
break;
case SMBUS_SIZE_BLOCK:

Tim Hockin

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Nov 24, 2008, 3:29:09 PM11/24/08
to iotool...@googlegroups.com
LGTM
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