Helper functions for I2C and SMBus transactions don't modify the i2c_client that is passed to them, so it can be marked const. Signed-off-by: Jean Delvare <khali@xxxxxxxxxxxx> --- drivers/i2c/i2c-core.c | 29 ++++++++++++++++------------- drivers/rtc/rtc-ds1307.c | 12 ++++++------ include/linux/i2c.h | 27 +++++++++++++++------------ 3 files changed, 37 insertions(+), 31 deletions(-) --- linux-2.6.37-rc8.orig/include/linux/i2c.h 2011-01-05 18:31:17.000000000 +0100 +++ linux-2.6.37-rc8/include/linux/i2c.h 2011-01-05 18:31:41.000000000 +0100 @@ -57,9 +57,10 @@ struct i2c_board_info; * transmit an arbitrary number of messages without interruption. * @count must be be less than 64k since msg.len is u16. */ -extern int i2c_master_send(struct i2c_client *client, const char *buf, +extern int i2c_master_send(const struct i2c_client *client, const char *buf, + int count); +extern int i2c_master_recv(const struct i2c_client *client, char *buf, int count); -extern int i2c_master_recv(struct i2c_client *client, char *buf, int count); /* Transfer num messages. */ @@ -78,23 +79,25 @@ extern s32 i2c_smbus_xfer(struct i2c_ada /* Now follow the 'nice' access routines. These also document the calling conventions of i2c_smbus_xfer. */ -extern s32 i2c_smbus_read_byte(struct i2c_client *client); -extern s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value); -extern s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command); -extern s32 i2c_smbus_write_byte_data(struct i2c_client *client, +extern s32 i2c_smbus_read_byte(const struct i2c_client *client); +extern s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value); +extern s32 i2c_smbus_read_byte_data(const struct i2c_client *client, + u8 command); +extern s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, u8 value); -extern s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command); -extern s32 i2c_smbus_write_word_data(struct i2c_client *client, +extern s32 i2c_smbus_read_word_data(const struct i2c_client *client, + u8 command); +extern s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, u16 value); /* Returns the number of read bytes */ -extern s32 i2c_smbus_read_block_data(struct i2c_client *client, +extern s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, u8 *values); -extern s32 i2c_smbus_write_block_data(struct i2c_client *client, +extern s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, u8 length, const u8 *values); /* Returns the number of read bytes */ -extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, +extern s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, u8 length, u8 *values); -extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, +extern s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, u8 length, const u8 *values); #endif /* I2C */ --- linux-2.6.37-rc8.orig/drivers/i2c/i2c-core.c 2011-01-05 18:31:17.000000000 +0100 +++ linux-2.6.37-rc8/drivers/i2c/i2c-core.c 2011-01-05 18:31:41.000000000 +0100 @@ -1362,7 +1362,7 @@ EXPORT_SYMBOL(i2c_transfer); * * Returns negative errno, or else the number of bytes written. */ -int i2c_master_send(struct i2c_client *client, const char *buf, int count) +int i2c_master_send(const struct i2c_client *client, const char *buf, int count) { int ret; struct i2c_adapter *adap = client->adapter; @@ -1389,7 +1389,7 @@ EXPORT_SYMBOL(i2c_master_send); * * Returns negative errno, or else the number of bytes read. */ -int i2c_master_recv(struct i2c_client *client, char *buf, int count) +int i2c_master_recv(const struct i2c_client *client, char *buf, int count) { struct i2c_adapter *adap = client->adapter; struct i2c_msg msg; @@ -1679,7 +1679,7 @@ static int i2c_smbus_check_pec(u8 cpec, * This executes the SMBus "receive byte" protocol, returning negative errno * else the byte received from the device. */ -s32 i2c_smbus_read_byte(struct i2c_client *client) +s32 i2c_smbus_read_byte(const struct i2c_client *client) { union i2c_smbus_data data; int status; @@ -1699,7 +1699,7 @@ EXPORT_SYMBOL(i2c_smbus_read_byte); * This executes the SMBus "send byte" protocol, returning negative errno * else zero on success. */ -s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value) +s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value) { return i2c_smbus_xfer(client->adapter, client->addr, client->flags, I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); @@ -1714,7 +1714,7 @@ EXPORT_SYMBOL(i2c_smbus_write_byte); * This executes the SMBus "read byte" protocol, returning negative errno * else a data byte received from the device. */ -s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command) +s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command) { union i2c_smbus_data data; int status; @@ -1735,7 +1735,8 @@ EXPORT_SYMBOL(i2c_smbus_read_byte_data); * This executes the SMBus "write byte" protocol, returning negative errno * else zero on success. */ -s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value) +s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, + u8 value) { union i2c_smbus_data data; data.byte = value; @@ -1753,7 +1754,7 @@ EXPORT_SYMBOL(i2c_smbus_write_byte_data) * This executes the SMBus "read word" protocol, returning negative errno * else a 16-bit unsigned "word" received from the device. */ -s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command) +s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command) { union i2c_smbus_data data; int status; @@ -1774,7 +1775,8 @@ EXPORT_SYMBOL(i2c_smbus_read_word_data); * This executes the SMBus "write word" protocol, returning negative errno * else zero on success. */ -s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value) +s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, + u16 value) { union i2c_smbus_data data; data.word = value; @@ -1793,7 +1795,8 @@ EXPORT_SYMBOL(i2c_smbus_write_word_data) * This executes the SMBus "process call" protocol, returning negative errno * else a 16-bit unsigned "word" received from the device. */ -s32 i2c_smbus_process_call(struct i2c_client *client, u8 command, u16 value) +s32 i2c_smbus_process_call(const struct i2c_client *client, u8 command, + u16 value) { union i2c_smbus_data data; int status; @@ -1821,7 +1824,7 @@ EXPORT_SYMBOL(i2c_smbus_process_call); * support this; its emulation through I2C messaging relies on a specific * mechanism (I2C_M_RECV_LEN) which may not be implemented. */ -s32 i2c_smbus_read_block_data(struct i2c_client *client, u8 command, +s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, u8 *values) { union i2c_smbus_data data; @@ -1848,7 +1851,7 @@ EXPORT_SYMBOL(i2c_smbus_read_block_data) * This executes the SMBus "block write" protocol, returning negative errno * else zero on success. */ -s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command, +s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, u8 length, const u8 *values) { union i2c_smbus_data data; @@ -1864,7 +1867,7 @@ s32 i2c_smbus_write_block_data(struct i2 EXPORT_SYMBOL(i2c_smbus_write_block_data); /* Returns the number of read bytes */ -s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, +s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, u8 length, u8 *values) { union i2c_smbus_data data; @@ -1884,7 +1887,7 @@ s32 i2c_smbus_read_i2c_block_data(struct } EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); -s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command, +s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, u8 length, const u8 *values) { union i2c_smbus_data data; --- linux-2.6.37-rc8.orig/drivers/rtc/rtc-ds1307.c 2011-01-05 18:31:17.000000000 +0100 +++ linux-2.6.37-rc8/drivers/rtc/rtc-ds1307.c 2011-01-05 18:31:41.000000000 +0100 @@ -106,9 +106,9 @@ struct ds1307 { struct i2c_client *client; struct rtc_device *rtc; struct work_struct work; - s32 (*read_block_data)(struct i2c_client *client, u8 command, + s32 (*read_block_data)(const struct i2c_client *client, u8 command, u8 length, u8 *values); - s32 (*write_block_data)(struct i2c_client *client, u8 command, + s32 (*write_block_data)(const struct i2c_client *client, u8 command, u8 length, const u8 *values); }; @@ -158,8 +158,8 @@ MODULE_DEVICE_TABLE(i2c, ds1307_id); #define BLOCK_DATA_MAX_TRIES 10 -static s32 ds1307_read_block_data_once(struct i2c_client *client, u8 command, - u8 length, u8 *values) +static s32 ds1307_read_block_data_once(const struct i2c_client *client, + u8 command, u8 length, u8 *values) { s32 i, data; @@ -172,7 +172,7 @@ static s32 ds1307_read_block_data_once(s return i; } -static s32 ds1307_read_block_data(struct i2c_client *client, u8 command, +static s32 ds1307_read_block_data(const struct i2c_client *client, u8 command, u8 length, u8 *values) { u8 oldvalues[I2C_SMBUS_BLOCK_MAX]; @@ -198,7 +198,7 @@ static s32 ds1307_read_block_data(struct return length; } -static s32 ds1307_write_block_data(struct i2c_client *client, u8 command, +static s32 ds1307_write_block_data(const struct i2c_client *client, u8 command, u8 length, const u8 *values) { u8 currvalues[I2C_SMBUS_BLOCK_MAX]; -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html