[PATCH v4 07/12] iio: dac: ad5686: add ldac gpio

[Rodrigo Alencar via B4 Relay]

From: Rodrigo Alencar <rodrigo.alencar@xxxxxxxxxx>

If wired LDAC, should be asserted when unused (pin is active-low), which
allows for synchronous DAC updates. This will be used to update all the
channels at the same time when adding buffer support.

Signed-off-by: Rodrigo Alencar <rodrigo.alencar@xxxxxxxxxx>
---
 drivers/iio/dac/ad5686.c | 6 ++++++
 drivers/iio/dac/ad5686.h | 4 ++++
 2 files changed, 10 insertions(+)

diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
index 8ad8931a3d7f..713fe71ad1e7 100644
--- a/drivers/iio/dac/ad5686.c
+++ b/drivers/iio/dac/ad5686.c
@@ -12,6 +12,7 @@
 #include <linux/dev_printk.h>
 #include <linux/errno.h>
 #include <linux/export.h>
+#include <linux/gpio/consumer.h>
 #include <linux/kstrtox.h>
 #include <linux/module.h>
 #include <linux/regulator/consumer.h>
@@ -521,6 +522,11 @@ int ad5686_probe(struct device *dev,
 	fsleep(1);
 	reset_control_deassert(rstc);
 
+	st->ldac_gpio = devm_gpiod_get_optional(dev, "ldac", GPIOD_OUT_HIGH);
+	if (IS_ERR(st->ldac_gpio))
+		return dev_err_probe(dev, PTR_ERR(st->ldac_gpio),
+				     "Failed to get LDAC GPIO\n");
+
 	/* Initialize masks to all ones */
 	st->pwr_down_mask = ~0;
 	st->pwr_down_mode = ~0;
diff --git a/drivers/iio/dac/ad5686.h b/drivers/iio/dac/ad5686.h
index a06fe7d89305..c424720f8f72 100644
--- a/drivers/iio/dac/ad5686.h
+++ b/drivers/iio/dac/ad5686.h
@@ -60,6 +60,8 @@ enum ad5686_regmap_type {
 	AD5686_REGMAP,
 };
 
+struct gpio_desc;
+
 struct ad5686_state;
 
 /**
@@ -119,6 +121,7 @@ extern const struct ad5686_chip_info ad5679r_chip_info;
  * @dev:		device instance
  * @chip_info:		chip model specific constants, available modes etc
  * @ops:		bus specific operations
+ * @ldac_gpio:		LDAC pin GPIO descriptor
  * @vref_mv:		actual reference voltage used
  * @pwr_down_mask:	power down mask
  * @pwr_down_mode:	current power down mode
@@ -131,6 +134,7 @@ struct ad5686_state {
 	struct device			*dev;
 	const struct ad5686_chip_info	*chip_info;
 	const struct ad5686_bus_ops	*ops;
+	struct gpio_desc		*ldac_gpio;
 	unsigned short			vref_mv;
 	unsigned int			pwr_down_mask;
 	unsigned int			pwr_down_mode;

-- 
2.43.0