i2c: Constify i2c_client where possible

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@linux-fr.org>
This commit is contained in:
Jean Delvare 2011-01-10 22:11:23 +01:00 committed by Jean Delvare
parent af5a60baae
commit 0cc43a1806
3 changed files with 37 additions and 31 deletions

View File

@ -1362,7 +1362,7 @@ EXPORT_SYMBOL(i2c_transfer);
* *
* Returns negative errno, or else the number of bytes written. * 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; int ret;
struct i2c_adapter *adap = client->adapter; 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. * 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_adapter *adap = client->adapter;
struct i2c_msg msg; struct i2c_msg msg;
@ -1679,7 +1679,7 @@ static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg)
* This executes the SMBus "receive byte" protocol, returning negative errno * This executes the SMBus "receive byte" protocol, returning negative errno
* else the byte received from the device. * 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; union i2c_smbus_data data;
int status; int status;
@ -1699,7 +1699,7 @@ EXPORT_SYMBOL(i2c_smbus_read_byte);
* This executes the SMBus "send byte" protocol, returning negative errno * This executes the SMBus "send byte" protocol, returning negative errno
* else zero on success. * 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, return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); 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 * This executes the SMBus "read byte" protocol, returning negative errno
* else a data byte received from the device. * 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; union i2c_smbus_data data;
int status; int status;
@ -1735,7 +1735,8 @@ EXPORT_SYMBOL(i2c_smbus_read_byte_data);
* This executes the SMBus "write byte" protocol, returning negative errno * This executes the SMBus "write byte" protocol, returning negative errno
* else zero on success. * 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; union i2c_smbus_data data;
data.byte = value; data.byte = value;
@ -1753,7 +1754,7 @@ EXPORT_SYMBOL(i2c_smbus_write_byte_data);
* This executes the SMBus "read word" protocol, returning negative errno * This executes the SMBus "read word" protocol, returning negative errno
* else a 16-bit unsigned "word" received from the device. * 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; union i2c_smbus_data data;
int status; int status;
@ -1774,7 +1775,8 @@ EXPORT_SYMBOL(i2c_smbus_read_word_data);
* This executes the SMBus "write word" protocol, returning negative errno * This executes the SMBus "write word" protocol, returning negative errno
* else zero on success. * 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; union i2c_smbus_data data;
data.word = value; data.word = value;
@ -1793,7 +1795,8 @@ EXPORT_SYMBOL(i2c_smbus_write_word_data);
* This executes the SMBus "process call" protocol, returning negative errno * This executes the SMBus "process call" protocol, returning negative errno
* else a 16-bit unsigned "word" received from the device. * 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; union i2c_smbus_data data;
int status; int status;
@ -1821,7 +1824,7 @@ EXPORT_SYMBOL(i2c_smbus_process_call);
* support this; its emulation through I2C messaging relies on a specific * support this; its emulation through I2C messaging relies on a specific
* mechanism (I2C_M_RECV_LEN) which may not be implemented. * 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) u8 *values)
{ {
union i2c_smbus_data data; 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 * This executes the SMBus "block write" protocol, returning negative errno
* else zero on success. * 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) u8 length, const u8 *values)
{ {
union i2c_smbus_data data; union i2c_smbus_data data;
@ -1864,7 +1867,7 @@ s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command,
EXPORT_SYMBOL(i2c_smbus_write_block_data); EXPORT_SYMBOL(i2c_smbus_write_block_data);
/* Returns the number of read bytes */ /* 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) u8 length, u8 *values)
{ {
union i2c_smbus_data data; union i2c_smbus_data data;
@ -1884,7 +1887,7 @@ s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command,
} }
EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); 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) u8 length, const u8 *values)
{ {
union i2c_smbus_data data; union i2c_smbus_data data;

View File

@ -106,9 +106,9 @@ struct ds1307 {
struct i2c_client *client; struct i2c_client *client;
struct rtc_device *rtc; struct rtc_device *rtc;
struct work_struct work; 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); 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); u8 length, const u8 *values);
}; };
@ -158,8 +158,8 @@ MODULE_DEVICE_TABLE(i2c, ds1307_id);
#define BLOCK_DATA_MAX_TRIES 10 #define BLOCK_DATA_MAX_TRIES 10
static s32 ds1307_read_block_data_once(struct i2c_client *client, u8 command, static s32 ds1307_read_block_data_once(const struct i2c_client *client,
u8 length, u8 *values) u8 command, u8 length, u8 *values)
{ {
s32 i, data; s32 i, data;
@ -172,7 +172,7 @@ static s32 ds1307_read_block_data_once(struct i2c_client *client, u8 command,
return i; 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 length, u8 *values)
{ {
u8 oldvalues[I2C_SMBUS_BLOCK_MAX]; u8 oldvalues[I2C_SMBUS_BLOCK_MAX];
@ -198,7 +198,7 @@ static s32 ds1307_read_block_data(struct i2c_client *client, u8 command,
return length; 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 length, const u8 *values)
{ {
u8 currvalues[I2C_SMBUS_BLOCK_MAX]; u8 currvalues[I2C_SMBUS_BLOCK_MAX];

View File

@ -57,9 +57,10 @@ struct i2c_board_info;
* transmit an arbitrary number of messages without interruption. * transmit an arbitrary number of messages without interruption.
* @count must be be less than 64k since msg.len is u16. * @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); int count);
extern int i2c_master_recv(struct i2c_client *client, char *buf, int count);
/* Transfer num messages. /* Transfer num messages.
*/ */
@ -78,23 +79,25 @@ extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
/* Now follow the 'nice' access routines. These also document the calling /* Now follow the 'nice' access routines. These also document the calling
conventions of i2c_smbus_xfer. */ conventions of i2c_smbus_xfer. */
extern s32 i2c_smbus_read_byte(struct i2c_client *client); extern s32 i2c_smbus_read_byte(const struct i2c_client *client);
extern s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value); extern s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value);
extern s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command); extern s32 i2c_smbus_read_byte_data(const struct i2c_client *client,
extern s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command);
extern s32 i2c_smbus_write_byte_data(const struct i2c_client *client,
u8 command, u8 value); u8 command, u8 value);
extern s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command); extern s32 i2c_smbus_read_word_data(const struct i2c_client *client,
extern s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command);
extern s32 i2c_smbus_write_word_data(const struct i2c_client *client,
u8 command, u16 value); u8 command, u16 value);
/* Returns the number of read bytes */ /* 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); 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); u8 command, u8 length, const u8 *values);
/* Returns the number of read bytes */ /* 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); 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, u8 command, u8 length,
const u8 *values); const u8 *values);
#endif /* I2C */ #endif /* I2C */