summaryrefslogtreecommitdiffstats
path: root/drivers
diff options
context:
space:
mode:
authorMauro Carvalho Chehab <mchehab+huawei@kernel.org>2021-04-23 17:19:11 +0200
committerMauro Carvalho Chehab <mchehab+huawei@kernel.org>2021-05-10 11:36:33 +0200
commitda3a1858c3a37c09446e1470c48352897d59d11b (patch)
treed00988558d73aa738cd9a9c8deaf0e2fcb97cf8c /drivers
parent6005a8e955e4e451e4bf6000affaab566d4cab5e (diff)
downloadlinux-stable-da3a1858c3a37c09446e1470c48352897d59d11b.tar.gz
linux-stable-da3a1858c3a37c09446e1470c48352897d59d11b.tar.bz2
linux-stable-da3a1858c3a37c09446e1470c48352897d59d11b.zip
media: i2c: ccs-core: fix pm_runtime_get_sync() usage count
The pm_runtime_get_sync() internally increments the dev->power.usage_count without decrementing it, even on errors. There is a bug at ccs_pm_get_init(): when this function returns an error, the stream is not started, and RPM usage_count should not be incremented. However, if the calls to v4l2_ctrl_handler_setup() return errors, it will be kept incremented. At ccs_suspend() the best is to 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") in order to properly decrement the usage counter automatically, in the case of errors. Fixes: 96e3a6b92f23 ("media: smiapp: Avoid maintaining power state information") Cc: stable@vger.kernel.org Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/media/i2c/ccs/ccs-core.c32
1 files changed, 22 insertions, 10 deletions
diff --git a/drivers/media/i2c/ccs/ccs-core.c b/drivers/media/i2c/ccs/ccs-core.c
index b05f409014b2..4a848ac2d2cd 100644
--- a/drivers/media/i2c/ccs/ccs-core.c
+++ b/drivers/media/i2c/ccs/ccs-core.c
@@ -1880,21 +1880,33 @@ static int ccs_pm_get_init(struct ccs_sensor *sensor)
struct i2c_client *client = v4l2_get_subdevdata(&sensor->src->sd);
int rval;
+ /*
+ * It can't use pm_runtime_resume_and_get() here, as the driver
+ * relies at the returned value to detect if the device was already
+ * active or not.
+ */
rval = pm_runtime_get_sync(&client->dev);
- if (rval < 0) {
- pm_runtime_put_noidle(&client->dev);
+ if (rval < 0)
+ goto error;
- return rval;
- } else if (!rval) {
- rval = v4l2_ctrl_handler_setup(&sensor->pixel_array->
- ctrl_handler);
- if (rval)
- return rval;
+ /* Device was already active, so don't set controls */
+ if (rval == 1)
+ return 0;
- return v4l2_ctrl_handler_setup(&sensor->src->ctrl_handler);
- }
+ /* Restore V4L2 controls to the previously suspended device */
+ rval = v4l2_ctrl_handler_setup(&sensor->pixel_array->ctrl_handler);
+ if (rval)
+ goto error;
+ rval = v4l2_ctrl_handler_setup(&sensor->src->ctrl_handler);
+ if (rval)
+ goto error;
+
+ /* Keep PM runtime usage_count incremented on success */
return 0;
+error:
+ pm_runtime_put(&client->dev);
+ return rval;
}
static int ccs_set_stream(struct v4l2_subdev *subdev, int enable)