diff options
Diffstat (limited to 'include/linux/i2c.h')
-rw-r--r-- | include/linux/i2c.h | 41 |
1 files changed, 27 insertions, 14 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 383510b4f083..be27062f8ed1 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -499,9 +499,13 @@ i2c_register_board_info(int busnum, struct i2c_board_info const *info, * @master_xfer: Issue a set of i2c transactions to the given I2C adapter * defined by the msgs array, with num messages available to transfer via * the adapter specified by adap. + * @master_xfer_atomic: same as @master_xfer. Yet, only using atomic context + * so e.g. PMICs can be accessed very late before shutdown. Optional. * @smbus_xfer: Issue smbus transactions to the given I2C adapter. If this * is not present, then the bus layer will try and convert the SMBus calls * into I2C transfers instead. + * @smbus_xfer_atomic: same as @smbus_xfer. Yet, only using atomic context + * so e.g. PMICs can be accessed very late before shutdown. Optional. * @functionality: Return the flags that this algorithm/adapter pair supports * from the I2C_FUNC_* flags. * @reg_slave: Register given client to I2C slave mode of this adapter @@ -512,25 +516,33 @@ i2c_register_board_info(int busnum, struct i2c_board_info const *info, * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584 * to name two of the most common. * - * The return codes from the @master_xfer field should indicate the type of - * error code that occurred during the transfer, as documented in the kernel - * Documentation file Documentation/i2c/fault-codes. + * The return codes from the @master_xfer{_atomic} fields should indicate the + * type of error code that occurred during the transfer, as documented in the + * Kernel Documentation file Documentation/i2c/fault-codes. */ struct i2c_algorithm { - /* If an adapter algorithm can't do I2C-level access, set master_xfer - to NULL. If an adapter algorithm can do SMBus access, set - smbus_xfer. If set to NULL, the SMBus protocol is simulated - using common I2C messages */ - /* master_xfer should return the number of messages successfully - processed, or a negative value on error */ + /* + * If an adapter algorithm can't do I2C-level access, set master_xfer + * to NULL. If an adapter algorithm can do SMBus access, set + * smbus_xfer. If set to NULL, the SMBus protocol is simulated + * using common I2C messages. + * + * master_xfer should return the number of messages successfully + * processed, or a negative value on error + */ int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, int num); - int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr, - unsigned short flags, char read_write, - u8 command, int size, union i2c_smbus_data *data); + int (*master_xfer_atomic)(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num); + int (*smbus_xfer)(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data); + int (*smbus_xfer_atomic)(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data); /* To determine what the adapter supports */ - u32 (*functionality) (struct i2c_adapter *); + u32 (*functionality)(struct i2c_adapter *adap); #if IS_ENABLED(CONFIG_I2C_SLAVE) int (*reg_slave)(struct i2c_client *client); @@ -682,7 +694,8 @@ struct i2c_adapter { int retries; struct device dev; /* the adapter device */ unsigned long locked_flags; /* owned by the I2C core */ -#define I2C_ALF_IS_SUSPENDED 0 +#define I2C_ALF_IS_SUSPENDED 0 +#define I2C_ALF_SUSPEND_REPORTED 1 int nr; char name[48]; |