Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1459146 > unrolled thread

[PATCH] pwm: Unexport children before chip removal

Back to article view | Back to linux.kernel

Contents

  [PATCH] pwm: Unexport children before chip removal David Hsu <davidhsu@google.com> - 2016-08-10 00:00 +0200
    Re: [PATCH] pwm: Unexport children before chip removal David Hsu <davidhsu@google.com> - 2016-08-11 01:00 +0200

#1459146 — [PATCH] 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>
---
 drivers/pwm/core.c  |  2 ++
 drivers/pwm/sysfs.c | 18 ++++++++++++++++++
 include/linux/pwm.h |  5 +++++
 3 files changed, 25 insertions(+)

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index ed337a8c..869af84 100644
--- 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 cb2b376..b3ccb8f 100644
--- a/drivers/pwm/sysfs.c
+++ b/drivers/pwm/sysfs.c
@@ -400,6 +400,24 @@ 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 c038ae3..16a0ae0 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -530,6 +530,7 @@ 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)
 {
@@ -538,6 +539,10 @@ 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 */
-- 
2.8.0.rc3.226.g39d4020

[toc] | [next] | [standalone]

#1460077

On Wed, Aug 10, 2016 at 1:49 AM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Tue, Aug 09, 2016 at 02:57:46PM -0700, David Hsu wrote:
>> 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>
>> ---
>>  drivers/pwm/core.c  |  2 ++
>>  drivers/pwm/sysfs.c | 18 ++++++++++++++++++
>>  include/linux/pwm.h |  5 +++++
>>  3 files changed, 25 insertions(+)
>
> Should this also go to the stable kernel releases?
>

Yes, this should go into stable.

Thanks,
David

> thanks,
>
> greg k-h

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web