Re: [PATCH v4 12/17] iio: adc: ad7768-1: Add GPIO controller support

[Marcelo Schmitt <marcelo.schmitt1@gmail.com>]

Hey Jonathan, 

The AD7768-1 GPIO controller support looks good to me.
Besides reviewing it, I've also inspired on your patch to implement GPIO
controller support for AD4170. I have one inline suggestion, though.

With that sorted out
Reviewed-by: Marcelo Schmitt <marcelo.schmitt@analog.com>

Thanks,
Marcelo

On 03/06, Jonathan Santos wrote:
> From: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
> 
> The AD7768-1 has the ability to control other local hardware (such as gain
> stages),to power down other blocks in the signal chain, or read local
> status signals over the SPI interface.
> 
> Add direct mode conditional locks in the gpio callbacks to prevent register
> access when the device is in buffered mode.
> 
> This change exports the AD7768-1's four gpios and makes them accessible
> at an upper layer.
> 
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
> Co-developed-by: Jonathan Santos <Jonathan.Santos@analog.com>
> Signed-off-by: Jonathan Santos <Jonathan.Santos@analog.com>
> ---
...
> ---
>  drivers/iio/adc/ad7768-1.c | 143 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 141 insertions(+), 2 deletions(-)
> 
...
> +static int ad7768_gpio_init(struct iio_dev *indio_dev)
> +{
> +	struct ad7768_state *st = iio_priv(indio_dev);
> +	int ret;
> +
> +	ret = regmap_write(st->regmap, AD7768_REG_GPIO_CONTROL,
> +			   AD7768_GPIO_UNIVERSAL_EN);
> +	if (ret)
> +		return ret;
> +
> +	st->gpiochip = (struct gpio_chip) {
> +		.label = "ad7768_1_gpios",
> +		.base = -1,
> +		.ngpio = 4,
> +		.parent = &st->spi->dev,
> +		.can_sleep = true,
> +		.direction_input = ad7768_gpio_direction_input,
> +		.direction_output = ad7768_gpio_direction_output,
> +		.get = ad7768_gpio_get,
> +		.set = ad7768_gpio_set,
> +		.owner = THIS_MODULE,
> +	};
> +
> +	return gpiochip_add_data(&st->gpiochip, indio_dev);
Use devm_gpiochip_add_data(), otherwise the gpiochip is not removed on device
detach.

> +}
> +