iio: ad9523: support for external signals via gpios

The AD9523 supports external signals for power-down mode, resetting the
device and sync timing.
This change add support for specifying values for these signals via the
gpios and initializing them default values.

For the reset signal, the GPIO is toggled during probing to re-initialize
the device to a known state.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Michael Hennerich 2018-07-27 09:41:09 +03:00 коммит произвёл Jonathan Cameron
Родитель 6d4abf1c0e
Коммит 6431975789
1 изменённых файлов: 30 добавлений и 0 удалений

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@ -12,6 +12,7 @@
#include <linux/sysfs.h>
#include <linux/spi/spi.h>
#include <linux/regulator/consumer.h>
#include <linux/gpio/consumer.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/delay.h>
@ -268,6 +269,9 @@ struct ad9523_state {
struct regulator *reg;
struct ad9523_platform_data *pdata;
struct iio_chan_spec ad9523_channels[AD9523_NUM_CHAN];
struct gpio_desc *pwrdown_gpio;
struct gpio_desc *reset_gpio;
struct gpio_desc *sync_gpio;
unsigned long vcxo_freq;
unsigned long vco_freq;
@ -988,6 +992,32 @@ static int ad9523_probe(struct spi_device *spi)
return ret;
}
st->pwrdown_gpio = devm_gpiod_get_optional(&spi->dev, "powerdown",
GPIOD_OUT_HIGH);
if (IS_ERR(st->pwrdown_gpio)) {
ret = PTR_ERR(st->pwrdown_gpio);
goto error_disable_reg;
}
st->reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset",
GPIOD_OUT_LOW);
if (IS_ERR(st->reset_gpio)) {
ret = PTR_ERR(st->reset_gpio);
goto error_disable_reg;
}
if (st->reset_gpio) {
udelay(1);
gpiod_direction_output(st->reset_gpio, 1);
}
st->sync_gpio = devm_gpiod_get_optional(&spi->dev, "sync",
GPIOD_OUT_HIGH);
if (IS_ERR(st->sync_gpio)) {
ret = PTR_ERR(st->sync_gpio);
goto error_disable_reg;
}
spi_set_drvdata(spi, indio_dev);
st->spi = spi;
st->pdata = pdata;