[PATCH v5 1/1] power: Emit changed uevent on wakeup_sysfs_add/remove

Abhishek Pandit-Subedi
2020-07-07T17:29:05Z

Udev rules that depend on the power/wakeup attribute don't get triggered
correctly if device_set_wakeup_capable is called after the device is
created. This can happen for several reasons (driver sets wakeup after
device is created, wakeup is changed on parent device, etc) and it seems
reasonable to emit a changed event when adding or removing attributes on
the device.

Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
---

Changes in v5:
- Ignore return from kobject_uevent when adding to sysfs

Changes in v4:
- Fix warning where returning from void and tested on device

Changes in v3:
- Simplified error handling

Changes in v2:
- Add newline at end of bt_dev_err

drivers/base/power/sysfs.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
index 24d25cf8ab1487..c7b24812523c9e 100644
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
/* sysfs entries for device PM */
#include <linux/device.h>
+#include <linux/kobject.h>
#include <linux/string.h>
#include <linux/export.h>
#include <linux/pm_qos.h>
@@ -739,12 +740,18 @@ int dpm_sysfs_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid)

int wakeup_sysfs_add(struct device *dev)
{
- return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
+ int ret = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
+
+ if (!ret)
+ kobject_uevent(&dev->kobj, KOBJ_CHANGE);
+
+ return ret;
}

void wakeup_sysfs_remove(struct device *dev)
{
sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
+ kobject_uevent(&dev->kobj, KOBJ_CHANGE);
}

int pm_qos_sysfs_add_resume_latency(struct device *dev)
--
2.27.0.212.ge8ba1cc988-goog