Re: [PATCH 3/3] media: i2c: imx219: Balance runtime PM use-count in resume callback

From: "Lad, Prabhakar" <prabhakar.csengg@gmail.com>
To: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>,
	Dave Stevenson <dave.stevenson@raspberrypi.com>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Pavel Machek <pavel@denx.de>,
	Andrey Konovalov <andrey.konovalov@linaro.org>,
	Sakari Ailus <sakari.ailus@linux.intel.com>,
	Jacopo Mondi <jacopo@jmondi.org>,
	Hans Verkuil <hverkuil-cisco@xs4all.nl>,
	linux-media <linux-media@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
	Biju Das <biju.das.jz@bp.renesas.com>
Subject: Re: [PATCH 3/3] media: i2c: imx219: Balance runtime PM use-count in resume callback
Date: Wed, 10 Mar 2021 14:01:02 +0000	[thread overview]
Message-ID: <CA+V-a8ua38zhCPW+Vu+8XmEUNt4rWGpPbg9BtojUK9_0SPhJuw@mail.gmail.com> (raw)
In-Reply-To: <YEjAL22jNXvpe23W@pendragon.ideasonboard.com>

Hi Laurent,

Thank you for the review.

On Wed, Mar 10, 2021 at 12:49 PM Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
>
> Hi Prabhakar,
>
> Thank you for the patch.
>
> On Wed, Mar 10, 2021 at 12:20:14PM +0000, Lad Prabhakar wrote:
> > The runtime PM use-count gets incremented in imx219_set_stream() call
> > when streaming is started this needs to be balanced by calling
> > pm_runtime_put() upon failure to start stream in resume callback.
> >
> > Fixes: 1283b3b8f82b9 ("media: i2c: Add driver for Sony IMX219 sensor")
> > Reported-by: Pavel Machek <pavel@denx.de>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > ---
> >  drivers/media/i2c/imx219.c | 3 +++
> >  1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
> > index 87c021de1460..afffc85cd265 100644
> > --- a/drivers/media/i2c/imx219.c
> > +++ b/drivers/media/i2c/imx219.c
> > @@ -1184,6 +1184,7 @@ static int __maybe_unused imx219_resume(struct device *dev)
> >  {
> >       struct v4l2_subdev *sd = dev_get_drvdata(dev);
> >       struct imx219 *imx219 = to_imx219(sd);
> > +     struct i2c_client *client;
> >       int ret;
> >
> >       mutex_lock(&imx219->mutex);
> > @@ -1197,7 +1198,9 @@ static int __maybe_unused imx219_resume(struct device *dev)
> >       return 0;
> >
> >  error:
> > +     client = v4l2_get_subdevdata(&imx219->sd);
> >       imx219_stop_streaming(imx219);
> > +     pm_runtime_put(&client->dev);
> >       imx219->streaming = false;
> >       __v4l2_ctrl_grab(imx219->vflip, false);
> >       __v4l2_ctrl_grab(imx219->hflip, false);
>
> Similarly to the __v4l2_ctrl_grab(), it could be better to move
> pm_runtime_put() to imx219_stop_streaming().
>
Agreed, moved this to imx219_stop_streaming().

Cheers,
Prabhakar

> --
> Regards,
>
> Laurent Pinchart