[PATCH 04/12] iio: adc: ad9467: fix reset gpio handling

Nuno Sa via B4 Relay
2023-11-21T10:17:30Z

From: Nuno Sa <nuno.sa@analog.com>

The reset gpio was being requested with GPIOD_OUT_LOW which means, not
asserted. Then it was being asserted but never de-asserted which means
the devices was left in reset. Fix it by de-asserting the gpio.

While at it, moved the handling to it's own function and dropped
'reset_gpio' from the 'struct ad9467_state' as we only need it during
probe. On top of that, refactored things so that we now request the gpio
asserted (i.e in reset) and then de-assert it.

Fixes: ad6797120238 ("iio: adc: ad9467: add support AD9467 ADC")
Signed-off-by: Nuno Sa <nuno.sa@analog.com>
---
drivers/iio/adc/ad9467.c | 33 ++++++++++++++++++++-------------
1 file changed, 20 insertions(+), 13 deletions(-)

diff --git a/drivers/iio/adc/ad9467.c b/drivers/iio/adc/ad9467.c
index 39eccc28debe..368ea57be117 100644
--- a/drivers/iio/adc/ad9467.c
+++ b/drivers/iio/adc/ad9467.c
@@ -121,7 +121,6 @@ struct ad9467_state {
unsigned int output_mode;

struct gpio_desc *pwrdown_gpio;
- struct gpio_desc *reset_gpio;
};

static int ad9467_spi_read(struct spi_device *spi, unsigned int reg)
@@ -378,6 +377,23 @@ static int ad9467_preenable_setup(struct adi_axi_adc_conv *conv)
return ad9467_outputmode_set(st->spi, st->output_mode);
}

+static int ad9467_reset(struct device *dev)
+{
+ struct gpio_desc *gpio;
+
+ gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(gpio))
+ return PTR_ERR(gpio);
+ if (!gpio)
+ return 0;
+
+ fsleep(1);
+ gpiod_direction_output(gpio, 0);
+ fsleep(10);
+
+ return 0;
+}
+
static int ad9467_probe(struct spi_device *spi)
{
const struct ad9467_chip_info *info;
@@ -408,18 +424,9 @@ static int ad9467_probe(struct spi_device *spi)
if (IS_ERR(st->pwrdown_gpio))
return PTR_ERR(st->pwrdown_gpio);

- st->reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset",
- GPIOD_OUT_LOW);
- if (IS_ERR(st->reset_gpio))
- return PTR_ERR(st->reset_gpio);
-
- if (st->reset_gpio) {
- udelay(1);
- ret = gpiod_direction_output(st->reset_gpio, 1);
- if (ret)
- return ret;
- mdelay(10);
- }
+ ret = ad9467_reset(&spi->dev);
+ if (ret)
+ return ret;

conv->chip_info = &info->axi_adc_info;

--
2.42.1