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Diffstat (limited to 'include/linux/i2c.h')
-rw-r--r--include/linux/i2c.h65
1 files changed, 62 insertions, 3 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 200cf13b00f6..fffdc270ca18 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -126,6 +126,11 @@ i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client,
u8 command, u8 length, u8 *values);
#endif /* I2C */
+enum i2c_alert_protocol {
+ I2C_PROTOCOL_SMBUS_ALERT,
+ I2C_PROTOCOL_SMBUS_HOST_NOTIFY,
+};
+
/**
* struct i2c_driver - represent an I2C device driver
* @class: What kind of i2c device we instantiate (for detect)
@@ -180,8 +185,11 @@ struct i2c_driver {
* The format and meaning of the data value depends on the protocol.
* For the SMBus alert protocol, there is a single bit of data passed
* as the alert response's low bit ("event flag").
+ * For the SMBus Host Notify protocol, the data corresponds to the
+ * 16-bit payload data reported by the slave device acting as master.
*/
- void (*alert)(struct i2c_client *, unsigned int data);
+ void (*alert)(struct i2c_client *, enum i2c_alert_protocol protocol,
+ unsigned int data);
/* a ioctl like command that can be used to perform specific functions
* with the device.
@@ -349,6 +357,11 @@ extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr);
extern struct i2c_client *
i2c_new_dummy(struct i2c_adapter *adap, u16 address);
+extern struct i2c_client *
+i2c_new_secondary_device(struct i2c_client *client,
+ const char *name,
+ u16 default_addr);
+
extern void i2c_unregister_device(struct i2c_client *);
#endif /* I2C */
@@ -524,6 +537,7 @@ struct i2c_adapter {
/* data fields that are valid for all devices */
struct rt_mutex bus_lock;
+ struct rt_mutex mux_lock;
int timeout; /* in jiffies */
int retries;
@@ -538,6 +552,10 @@ struct i2c_adapter {
struct i2c_bus_recovery_info *bus_recovery_info;
const struct i2c_adapter_quirks *quirks;
+
+ void (*lock_bus)(struct i2c_adapter *, unsigned int flags);
+ int (*trylock_bus)(struct i2c_adapter *, unsigned int flags);
+ void (*unlock_bus)(struct i2c_adapter *, unsigned int flags);
};
#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
@@ -567,8 +585,44 @@ i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *));
/* Adapter locking functions, exported for shared pin cases */
-void i2c_lock_adapter(struct i2c_adapter *);
-void i2c_unlock_adapter(struct i2c_adapter *);
+#define I2C_LOCK_ROOT_ADAPTER BIT(0)
+#define I2C_LOCK_SEGMENT BIT(1)
+
+/**
+ * i2c_lock_bus - Get exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT
+ * locks only this branch in the adapter tree
+ */
+static inline void
+i2c_lock_bus(struct i2c_adapter *adapter, unsigned int flags)
+{
+ adapter->lock_bus(adapter, flags);
+}
+
+/**
+ * i2c_unlock_bus - Release exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT
+ * unlocks only this branch in the adapter tree
+ */
+static inline void
+i2c_unlock_bus(struct i2c_adapter *adapter, unsigned int flags)
+{
+ adapter->unlock_bus(adapter, flags);
+}
+
+static inline void
+i2c_lock_adapter(struct i2c_adapter *adapter)
+{
+ i2c_lock_bus(adapter, I2C_LOCK_ROOT_ADAPTER);
+}
+
+static inline void
+i2c_unlock_adapter(struct i2c_adapter *adapter)
+{
+ i2c_unlock_bus(adapter, I2C_LOCK_ROOT_ADAPTER);
+}
/*flags for the client struct: */
#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
@@ -654,6 +708,11 @@ static inline int i2c_adapter_id(struct i2c_adapter *adap)
return adap->nr;
}
+static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg)
+{
+ return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0);
+}
+
/**
* module_i2c_driver() - Helper macro for registering a modular I2C driver
* @__i2c_driver: i2c_driver struct