diff options
| author | Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> | 2014-10-11 16:46:26 +0300 |
|---|---|---|
| committer | Lee Jones <lee.jones@linaro.org> | 2014-11-10 14:42:18 +0000 |
| commit | edf387b6d1a6993103ec95ed934a6daf559535f4 (patch) | |
| tree | 2510d4c001381b7eefcdcdd0a2bf16b77c00f579 | |
| parent | 0df1f2487d2f0d04703f142813d53615d62a1da4 (diff) | |
backlight: pwm: Clean-up pwm requested using legacy API
If PWM device is requested by means of legacy API pwm_request(), its
resources are not freed on module unbind, which may cause an oops on
access, e.g. by reading /sys/kernel/debug/pwm.
Reported-by: Dmitry Eremin-Solenikov <dmitry_eremin@mentor.com>
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
| -rw-r--r-- | drivers/video/backlight/pwm_bl.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index cb5ae4c08469..3a145a643e0d 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -34,6 +34,7 @@ struct pwm_bl_data { struct regulator *power_supply; struct gpio_desc *enable_gpio; unsigned int scale; + bool legacy; int (*notify)(struct device *, int brightness); void (*notify_after)(struct device *, @@ -274,7 +275,7 @@ static int pwm_backlight_probe(struct platform_device *pdev) pb->pwm = devm_pwm_get(&pdev->dev, NULL); if (IS_ERR(pb->pwm)) { dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n"); - + pb->legacy = true; pb->pwm = pwm_request(data->pwm_id, "pwm-backlight"); if (IS_ERR(pb->pwm)) { dev_err(&pdev->dev, "unable to request legacy PWM\n"); @@ -339,6 +340,8 @@ static int pwm_backlight_remove(struct platform_device *pdev) if (pb->exit) pb->exit(&pdev->dev); + if (pb->legacy) + pwm_free(pb->pwm); return 0; } |