diff options
| author | Jean Delvare <khali@linux-fr.org> | 2009-11-07 13:10:46 +0100 |
|---|---|---|
| committer | Jean Delvare <khali@linux-fr.org> | 2009-11-07 13:10:46 +0100 |
| commit | afa08974fe80c198b8650f73ed8ab59135ca10d0 (patch) | |
| tree | b649e06dc4cb9fa10b87f1914f05c6ca2ba0d910 | |
| parent | i2c-piix4: Modify code name SB900 to Hudson-2 (diff) | |
| download | linux-afa08974fe80c198b8650f73ed8ab59135ca10d0.tar.xz linux-afa08974fe80c198b8650f73ed8ab59135ca10d0.zip | |
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 <khali@linux-fr.org>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
| -rw-r--r-- | drivers/net/sfc/sfe4001.c | 4 | ||||
| -rw-r--r-- | include/linux/i2c.h | 18 |
2 files changed, 20 insertions, 2 deletions
diff --git a/drivers/net/sfc/sfe4001.c b/drivers/net/sfc/sfe4001.c index cee00ad49b57..49eb91b5f50c 100644 --- a/drivers/net/sfc/sfe4001.c +++ b/drivers/net/sfc/sfe4001.c @@ -188,7 +188,7 @@ static int sfn4111t_reset(struct efx_nic *efx) efx_oword_t reg; /* GPIO 3 and the GPIO register are shared with I2C, so block that */ - mutex_lock(&efx->i2c_adap.bus_lock); + i2c_lock_adapter(&efx->i2c_adap); /* Pull RST_N (GPIO 2) low then let it up again, setting the * FLASH_CFG_1 strap (GPIO 3) appropriately. Only change the @@ -204,7 +204,7 @@ static int sfn4111t_reset(struct efx_nic *efx) falcon_write(efx, ®, GPIO_CTL_REG_KER); msleep(1); - mutex_unlock(&efx->i2c_adap.bus_lock); + i2c_unlock_adapter(&efx->i2c_adap); ssleep(1); return 0; 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 */ |