Re: [PATCH] use mutex instead of semaphore in Sony PI driver

From: Mattia Dongili
Date: Wed Apr 25 2007 - 05:50:34 EST


On Tue, Apr 24, 2007 at 10:02:35PM +0200, Matthias Kaehlcke wrote:
> the Sony Programmable I/O Control driver uses a semaphore as
> mutex. use the mutex API instead of the (binary) semaphore
>
> Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@xxxxxxxxx>

Acked-by: Mattia Dongili <malattia@xxxxxxxx>

> --
>
> diff --git a/drivers/char/sonypi.c b/drivers/char/sonypi.c
> index 7823757..878d8d0 100644
> --- a/drivers/char/sonypi.c
> +++ b/drivers/char/sonypi.c
> @@ -477,7 +477,7 @@ static struct sonypi_device {
> u16 evtype_offset;
> int camera_power;
> int bluetooth_power;
> - struct semaphore lock;
> + struct mutex lock;
> struct kfifo *fifo;
> spinlock_t fifo_lock;
> wait_queue_head_t fifo_proc_list;
> @@ -884,7 +884,7 @@ int sonypi_camera_command(int command, u8 value)
> if (!camera)
> return -EIO;
>
> - down(&sonypi_device.lock);
> + mutex_lock(&sonypi_device.lock);
>
> switch (command) {
> case SONYPI_COMMAND_SETCAMERA:
> @@ -919,7 +919,7 @@ int sonypi_camera_command(int command, u8 value)
> command);
> break;
> }
> - up(&sonypi_device.lock);
> + mutex_unlock(&sonypi_device.lock);
> return 0;
> }
>
> @@ -938,20 +938,20 @@ static int sonypi_misc_fasync(int fd, struct file *filp, int on)
> static int sonypi_misc_release(struct inode *inode, struct file *file)
> {
> sonypi_misc_fasync(-1, file, 0);
> - down(&sonypi_device.lock);
> + mutex_lock(&sonypi_device.lock);
> sonypi_device.open_count--;
> - up(&sonypi_device.lock);
> + mutex_unlock(&sonypi_device.lock);
> return 0;
> }
>
> static int sonypi_misc_open(struct inode *inode, struct file *file)
> {
> - down(&sonypi_device.lock);
> + mutex_lock(&sonypi_device.lock);
> /* Flush input queue on first open */
> if (!sonypi_device.open_count)
> kfifo_reset(sonypi_device.fifo);
> sonypi_device.open_count++;
> - up(&sonypi_device.lock);
> + mutex_unlock(&sonypi_device.lock);
> return 0;
> }
>
> @@ -1001,7 +1001,7 @@ static int sonypi_misc_ioctl(struct inode *ip, struct file *fp,
> u8 val8;
> u16 val16;
>
> - down(&sonypi_device.lock);
> + mutex_lock(&sonypi_device.lock);
> switch (cmd) {
> case SONYPI_IOCGBRT:
> if (sonypi_ec_read(SONYPI_LCD_LIGHT, &val8)) {
> @@ -1101,7 +1101,7 @@ static int sonypi_misc_ioctl(struct inode *ip, struct file *fp,
> default:
> ret = -EINVAL;
> }
> - up(&sonypi_device.lock);
> + mutex_unlock(&sonypi_device.lock);
> return ret;
> }
>
> @@ -1330,7 +1330,7 @@ static int __devinit sonypi_probe(struct platform_device *dev)
> }
>
> init_waitqueue_head(&sonypi_device.fifo_proc_list);
> - init_MUTEX(&sonypi_device.lock);
> + mutex_init(&sonypi_device.lock);
> sonypi_device.bluetooth_power = -1;
>
> if ((pcidev = pci_get_device(PCI_VENDOR_ID_INTEL,
>
> --
> Matthias Kaehlcke
> Linux Application Developer
> Barcelona
>
> If liberty means anything at all, it means the
> right to tell people what they do not want to hear
> (George Orwell)
> .''`.
> using free software / Debian GNU/Linux | http://debian.org : :' :
> `. `'`
> gpg --keyserver pgp.mit.edu --recv-keys 47D8E5D4 `-
>
--
mattia
:wq!
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/