Staging: iio: adt7316: Use device tree data to set ldac_pin

Make the driver use device tree instead of the platform data.
Hence, use devm_gpiod_get_optional function to get the data from
device tree for ldac-pin and accordingly make the needed changes
in the driver.

Signed-off-by: Shreeya Patel <shreeya.patel23498@gmail.com>

Author: crazoes

drivers/staging/iio/addac/adt7316.c

@@ -177,7 +177,7 @@
 
 struct adt7316_chip_info {
 	struct adt7316_bus	bus;
-	u16			ldac_pin;
+	struct gpio_desc	*ldac_pin;
 	u16			int_mask;	/* 0x2f */
 	u8			config1;
 	u8			config2;
@@ -950,8 +950,8 @@ static ssize_t adt7316_store_update_DAC(struct device *dev,
 		if (ret)
 			return -EIO;
 	} else {
-		gpio_set_value(chip->ldac_pin, 0);
-		gpio_set_value(chip->ldac_pin, 1);
+		gpiod_set_value(chip->ldac_pin, 0);
+		gpiod_set_value(chip->ldac_pin, 1);
 	}
 
 	return len;
@@ -2122,7 +2122,13 @@ int adt7316_probe(struct device *dev, struct adt7316_bus *bus,
 	else
 		return -ENODEV;
 
-	chip->ldac_pin = adt7316_platform_data[1];
+	chip->ldac_pin = devm_gpiod_get_optional(dev, "ldac", GPIOD_OUT_LOW);
+	if (IS_ERR(chip->ldac_pin)) {
+		ret = PTR_ERR(chip->ldac_pin);
+		dev_err(dev, "Failed to request ldac GPIO: %d\n", ret);
+		return ret;
+	}
+
 	if (chip->ldac_pin) {
 		chip->config3 |= ADT7316_DA_EN_VIA_DAC_LDCA;
 		if ((chip->id & ID_FAMILY_MASK) == ID_ADT75XX)