Re: [PATCH] iio: resolver: ad2s1210: add reset gpio support

[Jonathan Cameron <jic23@kernel.org>]

On Tue, 17 Oct 2023 13:46:51 +0000
"Hennerich, Michael" <Michael.Hennerich@analog.com> wrote:

> > -----Original Message-----
> > From: David Lechner <dlechner@baylibre.com>
> > Sent: Montag, 16. Oktober 2023 17:43
> > To: linux-iio@vger.kernel.org
> > Cc: David Lechner <dlechner@baylibre.com>; Jonathan Cameron
> > <jic23@kernel.org>; Hennerich, Michael <Michael.Hennerich@analog.com>;
> > Sa, Nuno <Nuno.Sa@analog.com>; linux-kernel@vger.kernel.org
> > Subject: [PATCH] iio: resolver: ad2s1210: add reset gpio support
> > 
> > 
> > This adds support for the optional reset gpio to the ad2s1210 resolver driver. If
> > the gpio is present in the device tree, it is toggled during driver probe before the
> > reset of the device initialization. As per the devicetree bindings, it is expected for
> > the gpio to configured as active low.
> > 
> > Suggested-by: Michael Hennerich <Michael.Hennerich@analog.com>
> > Signed-off-by: David Lechner <dlechner@baylibre.com>
> > ---  
> 
> Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Applied and pushed out as testing for 0-day to poke at it.

Thanks,

Jonathan

> 
> >  drivers/iio/resolver/ad2s1210.c | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> > 
> > diff --git a/drivers/iio/resolver/ad2s1210.c b/drivers/iio/resolver/ad2s1210.c
> > index 8646389ec88d..a414eef12e5e 100644
> > --- a/drivers/iio/resolver/ad2s1210.c
> > +++ b/drivers/iio/resolver/ad2s1210.c
> > @@ -1426,6 +1426,7 @@ static int ad2s1210_setup_gpios(struct
> > ad2s1210_state *st)  {
> >  	struct device *dev = &st->sdev->dev;
> >  	struct gpio_descs *resolution_gpios;
> > +	struct gpio_desc *reset_gpio;
> >  	DECLARE_BITMAP(bitmap, 2);
> >  	int ret;
> > 
> > @@ -1481,6 +1482,17 @@ static int ad2s1210_setup_gpios(struct
> > ad2s1210_state *st)
> >  					     "failed to set resolution gpios\n");
> >  	}
> > 
> > +	/* If the optional reset GPIO is present, toggle it to do a hard reset. */
> > +	reset_gpio = devm_gpiod_get_optional(dev, "reset",
> > GPIOD_OUT_HIGH);
> > +	if (IS_ERR(reset_gpio))
> > +		return dev_err_probe(dev, PTR_ERR(reset_gpio),
> > +				     "failed to request reset GPIO\n");
> > +
> > +	if (reset_gpio) {
> > +		udelay(10);
> > +		gpiod_set_value(reset_gpio, 0);
> > +	}
> > +
> >  	return 0;
> >  }
> > 
> > --
> > 2.42.0  
>