4.19-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 12aceee1f412c3ddc7750155fec06c906f14ab51 ]
The runtime PM of this device is enabled after v4l2_ctrl_handler_setup(), and this makes this device's runtime PM usage count a negative value.
The ov7740_set_ctrl() tries to do something only if the device's runtime PM usage counter is nonzero.
ov7740_set_ctrl() { if (!pm_runtime_get_if_in_use(&client->dev)) return 0;
<do something>;
pm_runtime_put(&client->dev);
return ret; }
However, the ov7740_set_ctrl() is called by v4l2_ctrl_handler_setup() while the runtime PM of this device is not yet enabled. In this case, the pm_runtime_get_if_in_use() returns -EINVAL (!= 0).
Therefore we can't bail out of this function and the usage count is decreased by pm_runtime_put() without increment.
This fixes this problem by enabling the runtime PM of this device before v4l2_ctrl_handler_setup() so that the ov7740_set_ctrl() is always called when the runtime PM is enabled.
Cc: Wenyou Yang wenyou.yang@microchip.com Signed-off-by: Akinobu Mita akinobu.mita@gmail.com Tested-by: Eugen Hristev eugen.hristev@microchip.com Signed-off-by: Sakari Ailus sakari.ailus@linux.intel.com Signed-off-by: Mauro Carvalho Chehab mchehab+samsung@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/i2c/ov7740.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/media/i2c/ov7740.c b/drivers/media/i2c/ov7740.c index 605f3e25ad82..f5a1ee90a6c5 100644 --- a/drivers/media/i2c/ov7740.c +++ b/drivers/media/i2c/ov7740.c @@ -1101,6 +1101,9 @@ static int ov7740_probe(struct i2c_client *client, if (ret) return ret;
+ pm_runtime_set_active(&client->dev); + pm_runtime_enable(&client->dev); + ret = ov7740_detect(ov7740); if (ret) goto error_detect; @@ -1123,8 +1126,6 @@ static int ov7740_probe(struct i2c_client *client, if (ret) goto error_async_register;
- pm_runtime_set_active(&client->dev); - pm_runtime_enable(&client->dev); pm_runtime_idle(&client->dev);
return 0; @@ -1134,6 +1135,8 @@ error_async_register: error_init_controls: ov7740_free_controls(ov7740); error_detect: + pm_runtime_disable(&client->dev); + pm_runtime_set_suspended(&client->dev); ov7740_set_power(ov7740, 0); media_entity_cleanup(&ov7740->subdev.entity);