Date: Thu, 22 Dec 2016 01:29:31 +0200
From: Sakari Ailus <sakari.ailus@iki.fi>
To: Pavel Machek <pavel@ucw.cz>
Cc: ivo.g.dimitrov.75@gmail.com, sre@kernel.org, pali.rohar@gmail.com,
        linux-media@vger.kernel.org, galak@codeaurora.org,
        mchehab@osg.samsung.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v5] media: Driver for Toshiba et8ek8 5MP sensor
Message-ID: <20161221232930.GI16630@valkosipuli.retiisi.org.uk>
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 <20161214122451.GB27011@amd>
 <20161221134235.GH16630@valkosipuli.retiisi.org.uk>
 <20161221224216.GA4681@amd>
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On Wed, Dec 21, 2016 at 11:42:16PM +0100, Pavel Machek wrote:
> Hi!
> 
> > Thanks for the update.
> > 
> > On Wed, Dec 14, 2016 at 01:24:51PM +0100, Pavel Machek wrote:
> > ...
> > > +static int et8ek8_set_ctrl(struct v4l2_ctrl *ctrl)
> > > +{
> > > +	struct et8ek8_sensor *sensor =
> > > +		container_of(ctrl->handler, struct et8ek8_sensor, ctrl_handler);
> > > +
> > > +	switch (ctrl->id) {
> > > +	case V4L2_CID_GAIN:
> > > +		return et8ek8_set_gain(sensor, ctrl->val);
> > > +
> > > +	case V4L2_CID_EXPOSURE:
> > > +	{
> > > +		int rows;
> > > +		struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
> > > +		rows = ctrl->val;
> > > +		return et8ek8_i2c_write_reg(client, ET8EK8_REG_16BIT, 0x1243,
> > > +					    swab16(rows));
> > 
> > Why swab16()? Doesn't the et8ek8_i2c_write_reg() already do the right thing?
> > 
> > 16-bit writes aren't used elsewhere... and the register address and value
> > seem to have different endianness there, it looks like a bug to me in that
> > function.
> 
> I'm pretty sure I did not invent that swab16(). I checked, and
> exposure seems to work properly. I tried swapping the bytes, but then
> exposure did not seem to work. So this one seems to be correct.

I can fix that too, but I have no device to test. In terms of how the
hardware is controlled there should be no difference anyway.

-- 
Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk