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Diffstat (limited to 'include/linux/i2c.h')
-rw-r--r--include/linux/i2c.h46
1 files changed, 37 insertions, 9 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 8dc73013219..08be0d21864 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -35,6 +35,8 @@
#include <linux/sched.h> /* for completion */
#include <linux/mutex.h>
+extern struct bus_type i2c_bus_type;
+
/* --- General options ------------------------------------------------ */
struct i2c_msg;
@@ -43,6 +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
@@ -69,9 +72,8 @@ extern s32 i2c_smbus_xfer (struct i2c_adapter * adapter, u16 addr,
union i2c_smbus_data * data);
/* Now follow the 'nice' access routines. These also document the calling
- conventions of smbus_access. */
+ conventions of i2c_smbus_xfer. */
-extern s32 i2c_smbus_write_quick(struct i2c_client * client, u8 value);
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);
@@ -93,15 +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;
@@ -141,6 +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)
@@ -156,6 +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
@@ -173,6 +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)
@@ -350,10 +377,11 @@ static inline void i2c_set_adapdata (struct i2c_adapter *dev, void *data)
#define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
#define I2C_CLASS_TV_ANALOG (1<<1) /* bttv + friends */
#define I2C_CLASS_TV_DIGITAL (1<<2) /* dvb cards */
-#define I2C_CLASS_DDC (1<<3) /* i2c-matroxfb ? */
+#define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */
#define I2C_CLASS_CAM_ANALOG (1<<4) /* camera with analog CCD */
#define I2C_CLASS_CAM_DIGITAL (1<<5) /* most webcams */
#define I2C_CLASS_SOUND (1<<6) /* sound devices */
+#define I2C_CLASS_SPD (1<<7) /* SPD EEPROMs and similar */
#define I2C_CLASS_ALL (UINT_MAX) /* all of the above */
/* i2c_client_address_data is the struct for holding default client
@@ -537,7 +565,7 @@ union i2c_smbus_data {
/* and one more for user-space compatibility */
};
-/* smbus_access read or write markers */
+/* i2c_smbus_xfer read or write markers */
#define I2C_SMBUS_READ 1
#define I2C_SMBUS_WRITE 0