Re: [PATCH 2/3] [media] mt9v032: Do not unset master_mode

[Markus Pargmann <mpa@pengutronix.de>]

[-- Attachment #1: Type: text/plain, Size: 2086 bytes --]

Hi Laurent,

On Monday 09 November 2015 14:46:42 Laurent Pinchart wrote:
> Hi Markus,
> 
> Thank you for the patch.
> 
> On Friday 06 November 2015 14:13:44 Markus Pargmann wrote:
> > The power_on function of the driver resets the chip and sets the
> > CHIP_CONTROL register to 0. This switches the operating mode to slave.
> > The s_stream function sets the correct mode. But this caused problems on
> > a board where the camera chip is operated as master. The camera started
> > after a random amount of time streaming an image, I observed between 10
> > and 300 seconds.
> > 
> > The STRFM_OUT and STLN_OUT pins are not connected on this board which
> > may cause some issues in slave mode. I could not find any documentation
> > about this.
> > 
> > Keeping the chip in master mode after the reset helped to fix this
> > issue for me.
> > 
> > Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
> > ---
> >  drivers/media/i2c/mt9v032.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/media/i2c/mt9v032.c b/drivers/media/i2c/mt9v032.c
> > index 4aefde9634f5..943c3f39ea73 100644
> > --- a/drivers/media/i2c/mt9v032.c
> > +++ b/drivers/media/i2c/mt9v032.c
> > @@ -344,7 +344,8 @@ static int mt9v032_power_on(struct mt9v032 *mt9v032)
> >  	if (ret < 0)
> >  		return ret;
> > 
> > -	return regmap_write(map, MT9V032_CHIP_CONTROL, 0);
> > +	return regmap_write(map, MT9V032_CHIP_CONTROL,
> > +			    MT9V032_CHIP_CONTROL_MASTER_MODE);
> 
> This makes sense, but shouldn't you also fix the mt9v032_s_stream() function 
> then ? It clears the MT9V032_CHIP_CONTROL_MASTER_MODE bit when turning the 
> stream off.

Oh yes, thanks. Will fix it for the next version.

Best Regards,

Markus

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

[-- Attachment #2: This is a digitally signed message part. --]
[-- Type: application/pgp-signature, Size: 819 bytes --]