diff options
Diffstat (limited to 'include/linux/i2c.h')
| -rw-r--r-- | include/linux/i2c.h | 36 |
1 files changed, 31 insertions, 5 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 50cbab4b62b0..08be0d21864c 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -45,6 +45,7 @@ struct i2c_adapter; struct i2c_client; struct i2c_driver; union i2c_smbus_data; +struct i2c_board_info; /* * The master routines are the ones normally used to transmit data to devices @@ -94,15 +95,33 @@ extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client, u8 command, u8 length, const u8 *values); -/* - * A driver is capable of handling one or more physical devices present on - * I2C adapters. This information is used to inform the driver of adapter - * events. +/** + * struct i2c_driver - represent an I2C device driver + * @class: What kind of i2c device we instantiate (for detect) + * @detect: Callback for device detection + * @address_data: The I2C addresses to probe, ignore or force (for detect) + * @clients: List of detected clients we created (for i2c-core use only) * * The driver.owner field should be set to the module owner of this driver. * The driver.name field should be set to the name of this driver. + * + * For automatic device detection, both @detect and @address_data must + * be defined. @class should also be set, otherwise only devices forced + * with module parameters will be created. The detect function must + * fill at least the name field of the i2c_board_info structure it is + * handed upon successful detection, and possibly also the flags field. + * + * If @detect is missing, the driver will still work fine for enumerated + * devices. Detected devices simply won't be supported. This is expected + * for the many I2C/SMBus devices which can't be detected reliably, and + * the ones which can always be enumerated in practice. + * + * The i2c_client structure which is handed to the @detect callback is + * not a real i2c_client. It is initialized just enough so that you can + * call i2c_smbus_read_byte_data and friends on it. Don't do anything + * else with it. In particular, calling dev_dbg and friends on it is + * not allowed. */ - struct i2c_driver { int id; unsigned int class; @@ -142,6 +161,11 @@ struct i2c_driver { struct device_driver driver; const struct i2c_device_id *id_table; + + /* Device detection callback for automatic device creation */ + int (*detect)(struct i2c_client *, int kind, struct i2c_board_info *); + const struct i2c_client_address_data *address_data; + struct list_head clients; }; #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) @@ -157,6 +181,7 @@ struct i2c_driver { * @dev: Driver model device node for the slave. * @irq: indicates the IRQ generated by this device (if any) * @list: list of active/busy clients (DEPRECATED) + * @detected: member of an i2c_driver.clients list * @released: used to synchronize client releases & detaches and references * * An i2c_client identifies a single device (i.e. chip) connected to an @@ -174,6 +199,7 @@ struct i2c_client { struct device dev; /* the device structure */ int irq; /* irq issued by device */ struct list_head list; /* DEPRECATED */ + struct list_head detected; struct completion released; }; #define to_i2c_client(d) container_of(d, struct i2c_client, dev) |