Re: [PATCH v9 2/2] media: i2c: Add the ov7740 image sensor driver

[Sakari Ailus]

Hi Wenyou,

On Tue, Dec 19, 2017 at 02:11:28AM +0000, Wenyou.Yang@xxxxxxxxxxxxx wrote:
> Hi Sakari,
> 
> > -----Original Message-----
> > From: Sakari Ailus [mailto:sakari.ailus@xxxxxx]
> > Sent: 2017å12æ14æ 4:06
> > To: Wenyou Yang - A41535 <Wenyou.Yang@xxxxxxxxxxxxx>; Mauro Carvalho
> > Chehab <mchehab@xxxxxxxxxxxxxxxx>; Rob Herring <robh+dt@xxxxxxxxxx>;
> > Mark Rutland <mark.rutland@xxxxxxx>
> > Cc: linux-kernel@xxxxxxxxxxxxxxx; Nicolas Ferre - M43238
> > <Nicolas.Ferre@xxxxxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx; Jonathan Corbet
> > <corbet@xxxxxxx>; Hans Verkuil <hverkuil@xxxxxxxxx>; linux-arm-
> > kernel@xxxxxxxxxxxxxxxxxxx; Linux Media Mailing List <linux-
> > media@xxxxxxxxxxxxxxx>; Songjun Wu <songjun.wu@xxxxxxxxxxxxx>
> > Subject: Re: [PATCH v9 2/2] media: i2c: Add the ov7740 image sensor driver
> > 
> > Hi Wenyou,
> > 
> > Wenyou Yang wrote:
> > ...
> > > +static int ov7740_start_streaming(struct ov7740 *ov7740) {
> > > +	int ret;
> > > +
> > > +	if (ov7740->fmt) {
> > > +		ret = regmap_multi_reg_write(ov7740->regmap,
> > > +					     ov7740->fmt->regs,
> > > +					     ov7740->fmt->reg_num);
> > > +		if (ret)
> > > +			return ret;
> > > +	}
> > > +
> > > +	if (ov7740->frmsize) {
> > > +		ret = regmap_multi_reg_write(ov7740->regmap,
> > > +					     ov7740->frmsize->regs,
> > > +					     ov7740->frmsize->reg_num);
> > > +		if (ret)
> > > +			return ret;
> > > +	}
> > > +
> > > +	return __v4l2_ctrl_handler_setup(ov7740->subdev.ctrl_handler);
> > 
> > I believe you're still setting the controls after starting streaming.
> 
> Yes, it sees it does so.
> 
> The OV7740 sensor generates the stream pixel data at the constant frame
> rate, no such start or stop control.

That'd be odd but I guess hardware sometimes is. I'll apply the patches.

Thanks!

-- 
Sakari Ailus
e-mail: sakari.ailus@xxxxxx