From 392369019eb96e914234ea21eda806cb51a1073e Mon Sep 17 00:00:00 2001 From: Russell King Date: Sun, 6 Apr 2014 15:20:03 -0700 Subject: leds: leds-pwm: properly clean up after probe failure When probing with DT, we add each LED one at a time. If we find a LED without a PWM device (because it is not available yet) we fail the initialisation, unregister previous LEDs, and then by way of managed resources, we free the structure. The problem with this is we may have a scheduled and active work_struct in this structure, and this results in a nasty kernel oops. We need to cancel this work_struct properly upon cleanup - and the cleanup we require is the same cleanup as we do when the LED platform device is removed. Rather than writing this same code three times, move it into a separate function and use it in all three places. Fixes: c971ff185f64 ("leds: leds-pwm: Defer led_pwm_set() if PWM can sleep") Signed-off-by: Russell King Signed-off-by: Bryan Wu --- drivers/leds/leds-pwm.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/leds/leds-pwm.c b/drivers/leds/leds-pwm.c index dd1787368fb1..7d0aaed1e23a 100644 --- a/drivers/leds/leds-pwm.c +++ b/drivers/leds/leds-pwm.c @@ -83,6 +83,15 @@ static inline size_t sizeof_pwm_leds_priv(int num_leds) (sizeof(struct led_pwm_data) * num_leds); } +static void led_pwm_cleanup(struct led_pwm_priv *priv) +{ + while (priv->num_leds--) { + led_classdev_unregister(&priv->leds[priv->num_leds].cdev); + if (priv->leds[priv->num_leds].can_sleep) + cancel_work_sync(&priv->leds[priv->num_leds].work); + } +} + static int led_pwm_create_of(struct platform_device *pdev, struct led_pwm_priv *priv) { @@ -130,8 +139,7 @@ static int led_pwm_create_of(struct platform_device *pdev, return 0; err: - while (priv->num_leds--) - led_classdev_unregister(&priv->leds[priv->num_leds].cdev); + led_pwm_cleanup(priv); return ret; } @@ -199,8 +207,8 @@ static int led_pwm_probe(struct platform_device *pdev) return 0; err: - while (i--) - led_classdev_unregister(&priv->leds[i].cdev); + priv->num_leds = i; + led_pwm_cleanup(priv); return ret; } @@ -208,13 +216,8 @@ err: static int led_pwm_remove(struct platform_device *pdev) { struct led_pwm_priv *priv = platform_get_drvdata(pdev); - int i; - for (i = 0; i < priv->num_leds; i++) { - led_classdev_unregister(&priv->leds[i].cdev); - if (priv->leds[i].can_sleep) - cancel_work_sync(&priv->leds[i].work); - } + led_pwm_cleanup(priv); return 0; } -- cgit v1.2.3