[PATCH 3.16 146/370] PM / devfreq: Fix the bug of devfreq_add_device when governor is NULL

Ben Hutchings
2017-03-10T12:12:25Z

From: Chanwoo Choi <cw00.choi@samsung.com>

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: Ben Hutchings <ben@decadent.org.uk>
---
drivers/devfreq/devfreq.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -502,11 +502,16 @@ struct devfreq *devfreq_add_device(struc
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__);