pwm: Unexport children before chip removal

commit 0733424c9ba9f42242409d1ece780777272f7ea1 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 7831bc6b51dddb66960f8ef97fde2da1ce33572a..ec84ff8ad1b4a59ebbd9c93ea62edb2f714460f6 100644 (file)
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -321,6 +321,8 @@ 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 9c90886f41234153d044d24f94a9ae1e82efbd83..c20163b929911d386a4a226dbdc528704eadd451 100644 (file)
--- a/drivers/pwm/sysfs.c
+++ b/drivers/pwm/sysfs.c
@@ -350,6 +350,24 @@ 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 cfc3ed46cad20a26ffa131b51e25927ac6045f4c..aa8736d5b2f38ba1319a9f030da47ef18f537761 100644 (file)
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -331,6 +331,7 @@ 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)
 {
@@ -339,6 +340,10 @@ 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 */