Re: [v2 2/3] media: ov8856: Add devicetree support

Robert Foss
2020-03-31T13:37:39Z

On Thu, 26 Mar 2020 at 13:18, Robert Foss <robert.foss@linaro.org> wrote:
>
> Hey Fabio,
>
> On Fri, 13 Mar 2020 at 14:15, Fabio Estevam <festevam@gmail.com> wrote:
> >
> > Hi Robert,
> >
> > On Fri, Mar 13, 2020 at 8:04 AM Robert Foss <robert.foss@linaro.org> wrote:
> >
> > > +static int __ov8856_power_on(struct ov8856 *ov8856)
> > > +{
> > > + struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> > > + int ret;
> > > +
> > > + ret = clk_prepare_enable(ov8856->xvclk);
> > > + if (ret < 0) {
> > > + dev_err(&client->dev, "failed to enable xvclk\n");
> > > + return ret;
> > > + }
> > > +
> > > + gpiod_set_value_cansleep(ov8856->reset_gpio, GPIOD_OUT_HIGH);
> >
> > The parameter of gpiod_set_value_cansleep() is typically 0 (inactive
> > state) or 1 (active state), so:
> >
> > gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
>
> Ack

After testing this change, it breaks the driver during probing.
I had a quick look into GPIOD_OUT_HIGH & LOW definitions, and they
seem to never be 0 or 1.

https://elixir.bootlin.com/linux/latest/source/include/linux/gpio/consumer.h#L38

GPIOD_ASIS = 0,
GPIOD_IN = 1,
GPIOD_OUT_LOW = 3
GPIOD_OUT_HIGH = 7