[PATCH 4.19 007/115] PM / devfreq: Fix devfreq_notifier_call returning errno

Greg Kroah-Hartman
2020-01-07T21:18:44Z

From: Leonard Crestez <leonard.crestez@nxp.com>

[ Upstream commit e876e710ede23f670494331e062d643928e4142a ]

Notifier callbacks shouldn't return negative errno but one of the
NOTIFY_OK/DONE/BAD values.

The OPP core will ignore return values from notifiers but returning a
value that matches NOTIFY_STOP_MASK will stop the notification chain.

Fix by always returning NOTIFY_OK.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/devfreq/devfreq.c | 24 +++++++++++++-----------
1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 61fbaa89d7b4..34e297f28fc2 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -538,26 +538,28 @@ static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type,
void *devp)
{
struct devfreq *devfreq = container_of(nb, struct devfreq, nb);
- int ret;
+ int err = -EINVAL;

mutex_lock(&devfreq->lock);

devfreq->scaling_min_freq = find_available_min_freq(devfreq);
- if (!devfreq->scaling_min_freq) {
- mutex_unlock(&devfreq->lock);
- return -EINVAL;
- }
+ if (!devfreq->scaling_min_freq)
+ goto out;

devfreq->scaling_max_freq = find_available_max_freq(devfreq);
- if (!devfreq->scaling_max_freq) {
- mutex_unlock(&devfreq->lock);
- return -EINVAL;
- }
+ if (!devfreq->scaling_max_freq)
+ goto out;
+
+ err = update_devfreq(devfreq);

- ret = update_devfreq(devfreq);
+out:
mutex_unlock(&devfreq->lock);
+ if (err)
+ dev_err(devfreq->dev.parent,
+ "failed to update frequency from OPP notifier (%d)\n",
+ err);

- return ret;
+ return NOTIFY_OK;
}

/**
--
2.20.1