diff options
| author | Axel Lin <axel.lin@ingics.com> | 2013-08-19 10:07:46 +0800 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2013-08-28 13:13:05 +0200 |
| commit | 9b77ace409e1419c331209c4c8eb2c8bc990e9fd (patch) | |
| tree | 0bb3a43aee693c3fe68924a2dfc07254ef3f69b3 /drivers/pinctrl/core.c | |
| parent | 406044695fb286110324491f26f3e05048488809 (diff) | |
| download | lwn-9b77ace409e1419c331209c4c8eb2c8bc990e9fd.tar.gz lwn-9b77ace409e1419c331209c4c8eb2c8bc990e9fd.zip | |
pinctrl: core: Add proper mutex lock in pinctrl_request_gpio
This one is missed in commit 42fed7ba "pinctrl: move subsystem mutex to
pinctrl_dev struct".
I think this fixes the race between pin_free() and pin_request() calls.
It protects accessing the members of pctldev->desc.
(e.g. update desc->mux_usecount, desc->gpio_owner, desc->mux_owner, etc)
Current code grabs pctldev->mutex before calling pinmux_free_gpio(),
but did not grab the mutex while calling pinmux_request_gpio().
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/pinctrl/core.c')
| -rw-r--r-- | drivers/pinctrl/core.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index 7094a8129008..054d14b43db4 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -562,11 +562,15 @@ int pinctrl_request_gpio(unsigned gpio) return ret; } + mutex_lock(&pctldev->mutex); + /* Convert to the pin controllers number space */ pin = gpio_to_pin(range, gpio); ret = pinmux_request_gpio(pctldev, range, pin, gpio); + mutex_unlock(&pctldev->mutex); + return ret; } EXPORT_SYMBOL_GPL(pinctrl_request_gpio); |