Re: [PATCH V11 2/2] media: i2c: ov02a10: Add OV02A10 image sensor driver

From: Sakari Ailus <sakari.ailus@linux.intel.com>
To: Dongchun Zhu <dongchun.zhu@mediatek.com>
Cc: Tomasz Figa <tfiga@chromium.org>,
	linus.walleij@linaro.org, bgolaszewski@baylibre.com,
	mchehab@kernel.org, andriy.shevchenko@linux.intel.com,
	robh+dt@kernel.org, mark.rutland@arm.com, drinkcat@chromium.org,
	matthias.bgg@gmail.com, bingbu.cao@intel.com,
	srv_heupstream@mediatek.com, linux-mediatek@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org, sj.huang@mediatek.com,
	linux-media@vger.kernel.org, devicetree@vger.kernel.org,
	louis.kuo@mediatek.com, shengnan.wang@mediatek.com
Subject: Re: [PATCH V11 2/2] media: i2c: ov02a10: Add OV02A10 image sensor driver
Date: Wed, 1 Jul 2020 12:00:39 +0300	[thread overview]
Message-ID: <20200701090039.GM16711@paasikivi.fi.intel.com> (raw)
In-Reply-To: <1593593242.17166.48.camel@mhfsdcap03>

On Wed, Jul 01, 2020 at 04:47:22PM +0800, Dongchun Zhu wrote:
> Hi Tomasz, Sakari,
> 
> Thanks for the review.
> 
> On Tue, 2020-06-30 at 21:47 +0300, Sakari Ailus wrote:
> > On Tue, Jun 30, 2020 at 05:07:46PM +0000, Tomasz Figa wrote:
> > > Hi Dongchun,
> > > 
> > > On Tue, Jun 30, 2020 at 10:49:42AM +0800, Dongchun Zhu wrote:
> > > > Add a V4L2 sub-device driver for OV02A10 image sensor.
> > > > 
> > > > Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > > > ---
> > > >  MAINTAINERS                 |    1 +
> > > >  drivers/media/i2c/Kconfig   |   13 +
> > > >  drivers/media/i2c/Makefile  |    1 +
> > > >  drivers/media/i2c/ov02a10.c | 1052 +++++++++++++++++++++++++++++++++++++++++++
> > > >  4 files changed, 1067 insertions(+)
> > > >  create mode 100644 drivers/media/i2c/ov02a10.c
> > > 
> > > Thank you for the patch. Please see my comments inline.
> > > 
> > > [snip]
> > > > +static int ov02a10_entity_init_cfg(struct v4l2_subdev *sd,
> > > > +				   struct v4l2_subdev_pad_config *cfg)
> > > > +{
> > > > +	struct v4l2_subdev_format fmt = {
> > > > +		.which = cfg ? V4L2_SUBDEV_FORMAT_TRY : V4L2_SUBDEV_FORMAT_ACTIVE,
> > > 
> > > As we discussed before, this function is never called with cfg == NULL.
> > > Perhaps what we need here is to call ov02a10_set_fmt() twice, once for
> > > V4L2_SUBDEV_FORMAT_ACTIVE and then for V4L2_SUBDEV_FORMAT_TRY?
> > > 
> > > Sakari, would that be a proper implementation of this function?
> > 
> > It's fine to test fmt, but it should be only done if the driver calls the
> > function with ACTIVE format. I.e. it can be removed here, and always use
> > TRY.
> > 
> 
> Sorry for my late coming.
> The implementation of this function should be common(similar to
> OV2680/OV5645).
> If it needs to update to be more proper or clear, as user always sets
> format.which to ACTIVE when calling set_fmt, we could only reserve the
> TRY format in init_cfg like this:
> struct v4l2_subdev_format fmt = {
> 	which = V4L2_SUBDEV_FORMAT_TRY,

Yes, please.

-- 
Sakari Ailus