1 files changed, 29 insertions, 0 deletions

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index b556e0ab946f..a720d9921b47 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -46,6 +46,8 @@ struct i2c_client;
 struct i2c_driver;
 union i2c_smbus_data;
 struct i2c_board_info;
+enum i2c_slave_event;
+typedef int (*i2c_slave_cb_t)(struct i2c_client *, enum i2c_slave_event, u8 *);
 
 struct module;
 
@@ -209,6 +211,8 @@ struct i2c_driver {
  * @irq: indicates the IRQ generated by this device (if any)
  * @detected: member of an i2c_driver.clients list or i2c-core's
  *      userspace_devices list
+ * @slave_cb: Callback when I2C slave mode of an adapter is used. The adapter
+ *      calls it to pass on slave events to the slave driver.
  *
  * An i2c_client identifies a single device (i.e. chip) connected to an
  * i2c bus. The behaviour exposed to Linux is defined by the driver
@@ -224,6 +228,7 @@ struct i2c_client {
         struct device dev;              /* the device structure         */
         int irq;                        /* irq issued by device         */
         struct list_head detected;
+        i2c_slave_cb_t slave_cb;        /* callback for slave mode      */
 };
 #define to_i2c_client(d) container_of(d, struct i2c_client, dev)
 
@@ -246,6 +251,25 @@ static inline void i2c_set_clientdata(struct i2c_client *dev, void *data)
         dev_set_drvdata(&dev->dev, data);
 }
 
+/* I2C slave support */
+
+enum i2c_slave_event {
+        I2C_SLAVE_REQ_READ_START,
+        I2C_SLAVE_REQ_READ_END,
+        I2C_SLAVE_REQ_WRITE_START,
+        I2C_SLAVE_REQ_WRITE_END,
+        I2C_SLAVE_STOP,
+};
+
+extern int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb);
+extern int i2c_slave_unregister(struct i2c_client *client);
+
+static inline int i2c_slave_event(struct i2c_client *client,
+                                  enum i2c_slave_event event, u8 *val)
+{
+        return client->slave_cb(client, event, val);
+}
+
 /**
  * struct i2c_board_info - template for device creation
  * @type: chip type, to initialize i2c_client.name
@@ -352,6 +376,8 @@ i2c_register_board_info(int busnum, struct i2c_board_info const *info,
  *   into I2C transfers instead.
  * @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
  *
  * 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
@@ -377,6 +403,9 @@ struct i2c_algorithm {
 
         /* To determine what the adapter supports */
         u32 (*functionality) (struct i2c_adapter *);
+
+        int (*reg_slave)(struct i2c_client *client);
+        int (*unreg_slave)(struct i2c_client *client);
 };
 
 /**