iio: resolver: ad2s1210: add reset gpio support

This adds support for the optional reset gpio to the ad2s1210 resolver driver. If the gpio is present in the device tree, it is toggled during driver probe before the reset of the device initialization. As per the devicetree bindings, it is expected for the gpio to configured as active low. Suggested-by: Michael Hennerich <[email protected]> Signed-off-by: David Lechner <[email protected]> Acked-by: Michael Hennerich <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Cameron <[email protected]>
analogdevicesinc · Oct 30, 2023 · c8013a4 · c8013a4
1 parent 770c02b
commit c8013a4
Showing 1 changed file with 12 additions and 0 deletions.
diff --git a/drivers/iio/resolver/ad2s1210.c b/drivers/iio/resolver/ad2s1210.c
@@ -1426,6 +1426,7 @@ static int ad2s1210_setup_gpios(struct ad2s1210_state *st)
 {
 	struct device *dev = &st->sdev->dev;
 	struct gpio_descs *resolution_gpios;
+	struct gpio_desc *reset_gpio;
 	DECLARE_BITMAP(bitmap, 2);
 	int ret;
 
@@ -1481,6 +1482,17 @@ static int ad2s1210_setup_gpios(struct ad2s1210_state *st)
 					     "failed to set resolution gpios\n");
 	}
 
+	/* If the optional reset GPIO is present, toggle it to do a hard reset. */
+	reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(reset_gpio))
+		return dev_err_probe(dev, PTR_ERR(reset_gpio),
+				     "failed to request reset GPIO\n");
+
+	if (reset_gpio) {
+		udelay(10);
+		gpiod_set_value(reset_gpio, 0);
+	}
+
 	return 0;
 }