Commit 0733424c authored by David Hsu's avatar David Hsu Committed by Thierry Reding
Browse files

pwm: Unexport children before chip removal 



Exported pwm channels aren't removed before the pwmchip and are
leaked. This results in invalid sysfs files. This fix removes
all exported pwm channels before chip removal.

Signed-off-by: default avatarDavid Hsu <davidhsu@google.com>
Fixes: 76abbdde ("pwm: Add sysfs interface")
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent 29b4817d

drivers/pwm/core.c

+2 −0
Original line number Diff line number Diff line
@@ -339,6 +339,8 @@ int pwmchip_remove(struct pwm_chip *chip) 
	unsigned int i;

	int ret = 0;



	pwmchip_sysfs_unexport_children(chip);



	mutex_lock(&pwm_lock);



	for (i = 0; i < chip->npwm; i++) {

drivers/pwm/sysfs.c

+18 −0
Original line number Diff line number Diff line
@@ -409,6 +409,24 @@ void pwmchip_sysfs_unexport(struct pwm_chip *chip) 
	}

}



void pwmchip_sysfs_unexport_children(struct pwm_chip *chip)

{

	struct device *parent;

	unsigned int i;



	parent = class_find_device(&pwm_class, NULL, chip,

				   pwmchip_sysfs_match);

	if (!parent)

		return;



	for (i = 0; i < chip->npwm; i++) {

		struct pwm_device *pwm = &chip->pwms[i];



		if (test_bit(PWMF_EXPORTED, &pwm->flags))

			pwm_unexport_child(parent, pwm);

	}

}



static int __init pwm_sysfs_init(void)

{

	return class_register(&pwm_class);

include/linux/pwm.h

+5 −0
Original line number Diff line number Diff line
@@ -641,6 +641,7 @@ static inline void pwm_remove_table(struct pwm_lookup *table, size_t num) 
#ifdef CONFIG_PWM_SYSFS

void pwmchip_sysfs_export(struct pwm_chip *chip);

void pwmchip_sysfs_unexport(struct pwm_chip *chip);

void pwmchip_sysfs_unexport_children(struct pwm_chip *chip);

#else

static inline void pwmchip_sysfs_export(struct pwm_chip *chip)

{
@@ -649,6 +650,10 @@ static inline void pwmchip_sysfs_export(struct pwm_chip *chip) 
static inline void pwmchip_sysfs_unexport(struct pwm_chip *chip)

{

}



static inline void pwmchip_sysfs_unexport_children(struct pwm_chip *chip)

{

}

#endif /* CONFIG_PWM_SYSFS */



#endif /* __LINUX_PWM_H */