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: David Hsu <davidhsu@google.com>
Fixes: 76abbdde2d95 ("pwm: Add sysfs interface")
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 0dbd29e287dbbf495a28fa4b142fb407773b2f0d..172ef82458112c268782d24f55cd882904340ea8 100644 (file)
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -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++) {

diff --git a/drivers/pwm/sysfs.c b/drivers/pwm/sysfs.c
index 18ed725594c316ab71edafdafb5e1912714de7f1..0296d8178ae29d509306670c9bb85147c50f0633 100644 (file)
--- a/drivers/pwm/sysfs.c
+++ b/drivers/pwm/sysfs.c
@@ -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);

diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index f1bbae014889b67a219a73c1e76156aa53229024..2c6c5114c089456cf0d3bac380a922132b077b7d 100644 (file)
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -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 */