[PATCH] PM / devfreq: Don't delete sysfs group twice

[Chris Diamand <chris.diamand@arm.com>]

The 'userspace' governor adds a sysfs entry, which is removed when
the governor is changed, or the devfreq device is released. However,
when the latter occurs via device_unregister(), device_del() is
called first, which removes the sysfs entries recursively and deletes
the kobject.

This means we get an Oops when the governor calls
sysfs_remove_group() on the deleted kobject. Fix this by explicitly
stopping the governor in devfreq_remove_device(), *before* the
devfreq entry is removed.

Note that we can't just remove the call to sysfs_remove_group() in
the userspace governor, as it's needed for when the governor is
changed to one without a sysfs entry.

Signed-off-by: Chris Diamand <chris.diamand@arm.com>
---
 drivers/devfreq/devfreq.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 478006b..d8a817c 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -622,6 +622,12 @@ int devfreq_remove_device(struct devfreq *devfreq)
 	if (!devfreq)
 		return -EINVAL;
 
+	if (devfreq->governor) {
+		devfreq->governor->event_handler(devfreq,
+						 DEVFREQ_GOV_STOP, NULL);
+		devfreq->governor = NULL;
+	}
+
 	device_unregister(&devfreq->dev);
 
 	return 0;
-- 
1.9.1