From afa08974fe80c198b8650f73ed8ab59135ca10d0 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Sat, 7 Nov 2009 13:10:46 +0100 Subject: i2c: Add an interface to lock/unlock an I2C bus segment Some drivers need to be able to prevent access to an I2C bus segment for a specific period of time. Add an interface for them to do so without twiddling with i2c-core internals. Signed-off-by: Jean Delvare Acked-by: Ben Hutchings --- include/linux/i2c.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'include/linux') diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 57d41b0abce2..7b40cda57a70 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -361,6 +361,24 @@ static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data) dev_set_drvdata(&dev->dev, data); } +/** + * i2c_lock_adapter - Prevent access to an I2C bus segment + * @adapter: Target I2C bus segment + */ +static inline void i2c_lock_adapter(struct i2c_adapter *adapter) +{ + mutex_lock(&adapter->bus_lock); +} + +/** + * i2c_unlock_adapter - Reauthorize access to an I2C bus segment + * @adapter: Target I2C bus segment + */ +static inline void i2c_unlock_adapter(struct i2c_adapter *adapter) +{ + mutex_unlock(&adapter->bus_lock); +} + /*flags for the client struct: */ #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ -- cgit v1.2.3