diff options
Diffstat (limited to 'include/linux/i2c.h')
| -rw-r--r-- | include/linux/i2c.h | 93 |
1 files changed, 62 insertions, 31 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h index a3166100f0cc..388ce71a29a9 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -23,14 +23,13 @@ #include <linux/swab.h> /* for swab16 */ #include <uapi/linux/i2c.h> -extern struct bus_type i2c_bus_type; -extern struct device_type i2c_adapter_type; -extern struct device_type i2c_client_type; +extern const struct bus_type i2c_bus_type; +extern const struct device_type i2c_adapter_type; +extern const struct device_type i2c_client_type; /* --- General options ------------------------------------------------ */ struct i2c_msg; -struct i2c_algorithm; struct i2c_adapter; struct i2c_client; struct i2c_driver; @@ -304,7 +303,7 @@ struct i2c_driver { u32 flags; }; -#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) +#define to_i2c_driver(d) container_of_const(d, struct i2c_driver, driver) /** * struct i2c_client - represent an I2C slave device @@ -512,46 +511,54 @@ i2c_register_board_info(int busnum, struct i2c_board_info const *info, #endif /* I2C_BOARDINFO */ /** - * struct i2c_algorithm - represent I2C transfer method - * @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 + * struct i2c_algorithm - represent I2C transfer methods + * @xfer: Transfer a given number of messages defined by the msgs array via + * the specified adapter. + * @xfer_atomic: Same as @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 + * @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 - * @unreg_slave: Unregister given client from I2C slave mode of this adapter + * @reg_target: Register given client to local target mode of this adapter + * @unreg_target: Unregister given client from local target mode of this adapter + * + * @master_xfer: deprecated, use @xfer + * @master_xfer_atomic: deprecated, use @xfer_atomic + * @reg_slave: deprecated, use @reg_target + * @unreg_slave: deprecated, use @unreg_target * - * The following structs are for those who like to implement new bus drivers: * i2c_algorithm is the interface to a class of hardware solutions which can * 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{_atomic}`` fields should indicate the + * The return codes from the ``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.rst. Otherwise, the * number of messages executed should be returned. */ struct i2c_algorithm { /* - * If an adapter algorithm can't do I2C-level access, set master_xfer + * If an adapter algorithm can't do I2C-level access, set 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 (*master_xfer_atomic)(struct i2c_adapter *adap, + union { + int (*xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num); + int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num); + }; + union { + int (*xfer_atomic)(struct i2c_adapter *adap, struct i2c_msg *msgs, int num); + 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); @@ -563,8 +570,14 @@ struct i2c_algorithm { u32 (*functionality)(struct i2c_adapter *adap); #if IS_ENABLED(CONFIG_I2C_SLAVE) - int (*reg_slave)(struct i2c_client *client); - int (*unreg_slave)(struct i2c_client *client); + union { + int (*reg_target)(struct i2c_client *client); + int (*reg_slave)(struct i2c_client *client); + }; + union { + int (*unreg_target)(struct i2c_client *client); + int (*unreg_slave)(struct i2c_client *client); + }; #endif }; @@ -855,8 +868,6 @@ static inline void i2c_mark_adapter_resumed(struct i2c_adapter *adap) /* i2c adapter classes (bitmask) */ #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */ -#define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */ -#define I2C_CLASS_SPD (1<<7) /* Memory modules */ /* Warn users that the adapter doesn't support classes anymore */ #define I2C_CLASS_DEPRECATED (1<<8) @@ -935,7 +946,7 @@ static inline int i2c_adapter_id(struct i2c_adapter *adap) static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg) { - return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0); + return (msg->addr << 1) | (msg->flags & I2C_M_RD); } u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold); @@ -965,8 +976,6 @@ int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr); #define builtin_i2c_driver(__i2c_driver) \ builtin_driver(__i2c_driver, i2c_add_driver) -#endif /* I2C */ - /* must call put_device() when done with returned i2c_client device */ struct i2c_client *i2c_find_device_by_fwnode(struct fwnode_handle *fwnode); @@ -976,6 +985,28 @@ struct i2c_adapter *i2c_find_adapter_by_fwnode(struct fwnode_handle *fwnode); /* must call i2c_put_adapter() when done with returned i2c_adapter device */ struct i2c_adapter *i2c_get_adapter_by_fwnode(struct fwnode_handle *fwnode); +#else /* I2C */ + +static inline struct i2c_client * +i2c_find_device_by_fwnode(struct fwnode_handle *fwnode) +{ + return NULL; +} + +static inline struct i2c_adapter * +i2c_find_adapter_by_fwnode(struct fwnode_handle *fwnode) +{ + return NULL; +} + +static inline struct i2c_adapter * +i2c_get_adapter_by_fwnode(struct fwnode_handle *fwnode) +{ + return NULL; +} + +#endif /* !I2C */ + #if IS_ENABLED(CONFIG_OF) /* must call put_device() when done with returned i2c_client device */ static inline struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) |