On Mon, 27 Jan 2025 12:13:45 -0300
Jonathan Santos <Jonathan.Santos@xxxxxxxxxx> wrote:
> From: Sergiu Cuciurean <sergiu.cuciurean@xxxxxxxxxx>
>
> 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.
>
> This change exports the AD7768-1's four gpios and makes them accessible
> at an upper layer.
>
> Co-developed-by: Jonathan Santos <Jonathan.Santos@xxxxxxxxxx>
> Signed-off-by: Jonathan Santos <Jonathan.Santos@xxxxxxxxxx>
> Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@xxxxxxxxxx>
As David observed, the direct mode release calls are missing.
Also, there are a few places where you wrap lines much shorter than needed.
> +static int ad7768_gpio_direction_output(struct gpio_chip *chip,
> + unsigned int offset, int value)
> +{
> + struct iio_dev *indio_dev = gpiochip_get_data(chip);
> + struct ad7768_state *st = iio_priv(indio_dev);
> + int ret;
> +
> + ret = iio_device_claim_direct_mode(indio_dev);
> + if (ret)
> + return ret;
> +
> + return regmap_update_bits(st->regmap,
> + AD7768_REG_GPIO_CONTROL,
> + BIT(offset),
> + AD7768_GPIO_OUTPUT(offset));
Again, wrap less.
> +}
> +
> +static int ad7768_gpio_get(struct gpio_chip *chip, unsigned int offset)
> +{
> + struct iio_dev *indio_dev = gpiochip_get_data(chip);
> + struct ad7768_state *st = iio_priv(indio_dev);
> + unsigned int val;
> + int ret;
> +
> + ret = iio_device_claim_direct_mode(indio_dev);
You aren't releasing it. That should have deadlocked the second time
you called this.
> + if (ret)
> + return ret;
> +
> + ret = regmap_read(st->regmap, AD7768_REG_GPIO_CONTROL, &val);
> + if (ret < 0)
> + return ret;
> +
> + if (val & BIT(offset))
> + ret = regmap_read(st->regmap, AD7768_REG_GPIO_WRITE, &val);
> + else
> + ret = regmap_read(st->regmap, AD7768_REG_GPIO_READ, &val);
> + if (ret < 0)
> + return ret;
> +
> + return !!(val & BIT(offset));
> +}
> +
> +static void ad7768_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
> +{
> + struct iio_dev *indio_dev = gpiochip_get_data(chip);
> + struct ad7768_state *st = iio_priv(indio_dev);
> + unsigned int val;
> + int ret;
> +
> + ret = iio_device_claim_direct_mode(indio_dev);
As above, needs a matching release. May mean you want to factor
out the guts of this as a helper function so you can still do
direct returns on error.
> + if (ret)
> + return;
> +
> + ret = regmap_read(st->regmap, AD7768_REG_GPIO_CONTROL, &val);
> + if (ret < 0)
> + return;
> +
> + if (val & BIT(offset))
> + regmap_update_bits(st->regmap,
> + AD7768_REG_GPIO_WRITE,
> + BIT(offset),
> + (value << offset));
Wrap a little less and drop the unnecessary brackets.
regmap_update_bits(st->regmap, AD7768_REG_GPIO_WRITE,
BIT(offset), value << offset);
Also, check return value?
> +}
> +
> +
> +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 < 0)
> + return ret;
> +
> + st->gpio_avail_map = AD7768_GPIO_CONTROL_MSK;
> + st->gpiochip.label = "ad7768_1_gpios";
> + st->gpiochip.base = -1;
> + st->gpiochip.ngpio = 4;
> + st->gpiochip.parent = &st->spi->dev;
> + st->gpiochip.can_sleep = true;
> + st->gpiochip.direction_input = ad7768_gpio_direction_input;
> + st->gpiochip.direction_output = ad7768_gpio_direction_output;
> + st->gpiochip.get = ad7768_gpio_get;
> + st->gpiochip.set = ad7768_gpio_set;
> + st->gpiochip.request = ad7768_gpio_request;
> + st->gpiochip.owner = THIS_MODULE;
Might not be worth it but I'd be tempted to do
st->gpiochip = (struct gpio_chip) {
.label = "ad7768_1_gpios",
.base = -1,
.ngpio = 4,
...
};
perhaps. This one is entirely up to your preference.
> +
> + return gpiochip_add_data(&st->gpiochip, indio_dev);
> +}
> +
