PM / devfreq: Fix the bug of devfreq_add_device when governor is NULL

commit 73613b16cb5c5d5a659fc8832eff99eead3f9afb upstream.

This patch fixes the bug of devfreq_add_device(). The devfreq device must
have the default governor. If find_devfreq_governor() returns error,
devfreq_add_device() fail to add the devfreq instance.

Fixes: 1b5c1be2c88e (PM / devfreq: map devfreq drivers to governor using name)
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 10 insertions, 5 deletions

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index bf3ea7603a58..712592cef1a2 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -593,11 +593,16 @@ struct devfreq *devfreq_add_device(struct device *dev,
         list_add(&devfreq->node, &devfreq_list);
 
         governor = find_devfreq_governor(devfreq->governor_name);
-        if (!IS_ERR(governor))
-                devfreq->governor = governor;
-        if (devfreq->governor)
-                err = devfreq->governor->event_handler(devfreq,
-                                        DEVFREQ_GOV_START, NULL);
+        if (IS_ERR(governor)) {
+                dev_err(dev, "%s: Unable to find governor for the device\n",
+                        __func__);
+                err = PTR_ERR(governor);
+                goto err_init;
+        }
+
+        devfreq->governor = governor;
+        err = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_START,
+                                                NULL);
         if (err) {
                 dev_err(dev, "%s: Unable to start governor for the device\n",
                         __func__);