Re: [PATCH 2/3] leds: lp5521/5523: Remove duplicate mutex

From: Bryan Wu
Date: Mon Dec 02 2013 - 14:40:45 EST


On Wed, Nov 20, 2013 at 10:14 PM, Milo Kim <milo.kim@xxxxxx> wrote:
> It can be a problem when a pattern is loaded via the firmware interface.
> LP55xx common driver has already locked the mutex in 'lp55xx_firmware_loaded()'.
> So it should be deleted.
>

Looks like lp5521_update_program_memory() will be called by
store_engine_load() without holding a lock after this change, is this
correct? I think you need also update store_engine_load() to hold the
lock when calling lp5521_update_program_memory().

Thanks,
-Bryan

> Cc: Pali Rohár <pali.rohar@xxxxxxxxx>
> Signed-off-by: Milo Kim <milo.kim@xxxxxx>
> ---
> drivers/leds/leds-lp5521.c | 4 ----
> drivers/leds/leds-lp5523.c | 4 ----
> 2 files changed, 8 deletions(-)
>
> diff --git a/drivers/leds/leds-lp5521.c b/drivers/leds/leds-lp5521.c
> index 26f89ac..4c45ed9 100644
> --- a/drivers/leds/leds-lp5521.c
> +++ b/drivers/leds/leds-lp5521.c
> @@ -258,8 +258,6 @@ static int lp5521_update_program_memory(struct lp55xx_chip *chip,
> if (i % 2)
> goto err;
>
> - mutex_lock(&chip->lock);
> -
> for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
> ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
> if (ret) {
> @@ -268,8 +266,6 @@ static int lp5521_update_program_memory(struct lp55xx_chip *chip,
> }
> }
>
> - mutex_unlock(&chip->lock);
> -
> return size;
>
> err:
> diff --git a/drivers/leds/leds-lp5523.c b/drivers/leds/leds-lp5523.c
> index 2ce1723..7a3b369 100644
> --- a/drivers/leds/leds-lp5523.c
> +++ b/drivers/leds/leds-lp5523.c
> @@ -351,8 +351,6 @@ static int lp5523_update_program_memory(struct lp55xx_chip *chip,
> if (i % 2)
> goto err;
>
> - mutex_lock(&chip->lock);
> -
> for (i = 0; i < LP5523_PROGRAM_LENGTH; i++) {
> ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
> if (ret) {
> @@ -361,8 +359,6 @@ static int lp5523_update_program_memory(struct lp55xx_chip *chip,
> }
> }
>
> - mutex_unlock(&chip->lock);
> -
> return size;
>
> err:
> --
> 1.7.9.5
>
--
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/