diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-01-21 09:33:38 +0000 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-02-18 23:15:32 +0000 |
| commit | cae154767a96563d33924872aacfdc63d584f707 (patch) | |
| tree | 5071f9b5c462bb48b8f6539aeb62664a3e7ab20a | |
| parent | ddb1e04a35846b6c5b6039e92555dafaf6ee03d2 (diff) | |
| download | linux-cae154767a96563d33924872aacfdc63d584f707.tar.bz2 | |
MFD: ucb1x00-core: use mutexes instead of semaphores
Convert the ucb1x00 driver to use mutexes rather than the depreciated
semaphores for exclusive access to the ADC.
Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| -rw-r--r-- | drivers/mfd/ucb1x00-core.c | 15 | ||||
| -rw-r--r-- | include/linux/mfd/ucb1x00.h | 4 |
2 files changed, 9 insertions, 10 deletions
diff --git a/drivers/mfd/ucb1x00-core.c b/drivers/mfd/ucb1x00-core.c index c2757c11ce7b..7386f822d4cd 100644 --- a/drivers/mfd/ucb1x00-core.c +++ b/drivers/mfd/ucb1x00-core.c @@ -27,7 +27,6 @@ #include <linux/mutex.h> #include <linux/mfd/ucb1x00.h> #include <linux/gpio.h> -#include <linux/semaphore.h> static DEFINE_MUTEX(ucb1x00_mutex); static LIST_HEAD(ucb1x00_drivers); @@ -99,7 +98,7 @@ void ucb1x00_io_write(struct ucb1x00 *ucb, unsigned int set, unsigned int clear) * ucb1x00_enable must have been called to enable the comms * before using this function. * - * This function does not take any semaphores or spinlocks. + * This function does not take any mutexes or spinlocks. */ unsigned int ucb1x00_io_read(struct ucb1x00 *ucb) { @@ -183,7 +182,7 @@ static int ucb1x00_gpio_direction_output(struct gpio_chip *chip, unsigned offset * Any code wishing to use the ADC converter must call this * function prior to using it. * - * This function takes the ADC semaphore to prevent two or more + * This function takes the ADC mutex to prevent two or more * concurrent uses, and therefore may sleep. As a result, it * can only be called from process context, not interrupt * context. @@ -193,7 +192,7 @@ static int ucb1x00_gpio_direction_output(struct gpio_chip *chip, unsigned offset */ void ucb1x00_adc_enable(struct ucb1x00 *ucb) { - down(&ucb->adc_sem); + mutex_lock(&ucb->adc_mutex); ucb->adc_cr |= UCB_ADC_ENA; @@ -215,7 +214,7 @@ void ucb1x00_adc_enable(struct ucb1x00 *ucb) * complete (2 frames max without sync). * * If called for a synchronised ADC conversion, it may sleep - * with the ADC semaphore held. + * with the ADC mutex held. */ unsigned int ucb1x00_adc_read(struct ucb1x00 *ucb, int adc_channel, int sync) { @@ -243,7 +242,7 @@ unsigned int ucb1x00_adc_read(struct ucb1x00 *ucb, int adc_channel, int sync) * ucb1x00_adc_disable - disable the ADC converter * @ucb: UCB1x00 structure describing chip * - * Disable the ADC converter and release the ADC semaphore. + * Disable the ADC converter and release the ADC mutex. */ void ucb1x00_adc_disable(struct ucb1x00 *ucb) { @@ -251,7 +250,7 @@ void ucb1x00_adc_disable(struct ucb1x00 *ucb) ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr); ucb1x00_disable(ucb); - up(&ucb->adc_sem); + mutex_unlock(&ucb->adc_mutex); } /* @@ -560,7 +559,7 @@ static int ucb1x00_probe(struct mcp *mcp) spin_lock_init(&ucb->lock); spin_lock_init(&ucb->io_lock); - sema_init(&ucb->adc_sem, 1); + mutex_init(&ucb->adc_mutex); ucb->id = id; ucb->mcp = mcp; diff --git a/include/linux/mfd/ucb1x00.h b/include/linux/mfd/ucb1x00.h index fd088cc6a4ca..a4b954381c2f 100644 --- a/include/linux/mfd/ucb1x00.h +++ b/include/linux/mfd/ucb1x00.h @@ -12,7 +12,7 @@ #include <linux/mfd/mcp.h> #include <linux/gpio.h> -#include <linux/semaphore.h> +#include <linux/mutex.h> #define UCB_IO_DATA 0x00 #define UCB_IO_DIR 0x01 @@ -124,7 +124,7 @@ struct ucb1x00 { spinlock_t lock; struct mcp *mcp; unsigned int irq; - struct semaphore adc_sem; + struct mutex adc_mutex; spinlock_t io_lock; u16 id; u16 io_dir; |