Merge branch 'for-linus' of git://git.kernel.dk/linux-block

[deliverable/linux.git] / include / linux / i2c.h

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 200cf13b00f620dae9ea8ecbd15e71d26ffb4a3a..96a25ae14494cc889dc002d965f79c6473296e8a 100644 (file)
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -524,6 +524,7 @@ 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 +539,10 @@ 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 +572,44 @@ 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 +695,11 @@ 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