[Linux-stm32] [PATCH] media: ov5640: fix MIPI power sequence

[Jacopo Mondi]

Hi Hugues, Sakari,

On Wed, Oct 07, 2020 at 06:01:03PM +0300, Sakari Ailus wrote:
> Hi Hugues,
>
> On Wed, Oct 07, 2020 at 04:43:18PM +0200, Hugues Fruchet wrote:
> > fixes: b1751ae652fb ("media: i2c: ov5640: Separate out mipi configuration from s_power")
>
> Fixes: ...
>
> And preferrably before Sob line.
>
> >
> > Fix ov5640_write_reg()return value unchecked at power off.
> > Reformat code to keep register access below the register description.
>
> If there's an error, I wouldn't stop turning things off, but just proceed.
> The caller will ignore the error in that case anyway. This changes with the
> patch.

Agreed, I think it's best to continue instead of bailing out as we're
in a power-off path

>
> >
> > Signed-off-by: Hugues Fruchet <hugues.fruchet at st.com>
> > Change-Id: I12db67c416c3d63eadee400a3c89aaf48c5b1469
>
> This was probably not intended to be here.
>
> > ---
> >  drivers/media/i2c/ov5640.c | 17 ++++++-----------
> >  1 file changed, 6 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
> > index 8d0254d..f34e62e 100644
> > --- a/drivers/media/i2c/ov5640.c
> > +++ b/drivers/media/i2c/ov5640.c
> > @@ -1940,14 +1940,6 @@ static int ov5640_set_power_mipi(struct ov5640_dev *sensor, bool on)
> >  {
> >  	int ret;
> >
> > -	if (!on) {
> > -		/* Reset MIPI bus settings to their default values. */
> > -		ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00, 0x58);
> > -		ov5640_write_reg(sensor, OV5640_REG_MIPI_CTRL00, 0x04);
> > -		ov5640_write_reg(sensor, OV5640_REG_PAD_OUTPUT00, 0x00);
> > -		return 0;
> > -	}
> > -
> >  	/*
> >  	 * Power up MIPI HS Tx and LS Rx; 2 data lanes mode
> >  	 *
> > @@ -1958,7 +1950,8 @@ static int ov5640_set_power_mipi(struct ov5640_dev *sensor, bool on)
> >  	 * [3] = 0	: Power up MIPI LS Rx
> >  	 * [2] = 0	: MIPI interface disabled
> >  	 */
> > -	ret = ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00, 0x40);
> > +	ret = ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00,
> > +			       on ? 0x40 : 0x58);
> >  	if (ret)
> >  		return ret;
> >
> > @@ -1969,7 +1962,8 @@ static int ov5640_set_power_mipi(struct ov5640_dev *sensor, bool on)
> >  	 * [5] = 1	: Gate clock when 'no packets'
> >  	 * [2] = 1	: MIPI bus in LP11 when 'no packets'
> >  	 */
> > -	ret = ov5640_write_reg(sensor, OV5640_REG_MIPI_CTRL00, 0x24);
> > +	ret = ov5640_write_reg(sensor, OV5640_REG_MIPI_CTRL00,
> > +			       on ? 0x24 : 0x04);
> >  	if (ret)
> >  		return ret;
> >
> > @@ -1981,7 +1975,8 @@ static int ov5640_set_power_mipi(struct ov5640_dev *sensor, bool on)
> >  	 * [5] = 1	: MIPI data lane 1 in LP11 when 'sleeping'
> >  	 * [4] = 1	: MIPI clock lane in LP11 when 'sleeping'
> >  	 */
> > -	ret = ov5640_write_reg(sensor, OV5640_REG_PAD_OUTPUT00, 0x70);
> > +	ret = ov5640_write_reg(sensor, OV5640_REG_PAD_OUTPUT00,
> > +			       on ? 0x70 : 0x00);
> >  	if (ret)
> >  		return ret;
> >
>
> --
> Kind regards,
>
> Sakari Ailus