[PATCH v4 12/79] media: renesas-ceu: Properly check for PM errors

From: Mauro Carvalho Chehab
Date: Wed Apr 28 2021 - 10:54:24 EST


Right now, the driver just assumes that PM runtime resume
worked, but it may fail.

Well, the pm_runtime_get_sync() internally increments the
dev->power.usage_count without decrementing it, even on errors.

So, using it is tricky. Let's replace it by the new
pm_runtime_resume_and_get(), introduced by:
commit dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
and return an error if something bad happens.

This should ensure that the PM runtime usage_count will be
properly decremented if an error happens at open time.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
---
drivers/media/platform/renesas-ceu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/renesas-ceu.c b/drivers/media/platform/renesas-ceu.c
index cd137101d41e..17f01b6e3fe0 100644
--- a/drivers/media/platform/renesas-ceu.c
+++ b/drivers/media/platform/renesas-ceu.c
@@ -1099,10 +1099,10 @@ static int ceu_open(struct file *file)

mutex_lock(&ceudev->mlock);
/* Causes soft-reset and sensor power on on first open */
- pm_runtime_get_sync(ceudev->dev);
+ ret = pm_runtime_resume_and_get(ceudev->dev);
mutex_unlock(&ceudev->mlock);

- return 0;
+ return ret;
}

static int ceu_release(struct file *file)
--
2.30.2