Merge tag 'gnss-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/johan/gnss

Pull GNSS updates from Johan Hovold:

 - support for the reset pin found on some u-blox receivers

 - use new regulator helper for the u-blox backup supply

* tag 'gnss-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/johan/gnss:
  gnss: ubx: add support for the reset gpio
  dt-bindings: gnss: u-blox: add "reset-gpios" binding
  gnss: ubx: use new helper to remove open coded regulator handling

Documentation/devicetree/bindings/gnss/u-blox,neo-6m.yaml

@@ -28,6 +28,9 @@ properties:
       port or the USB host-controller port to which this device is attached,
       depending on the bus used. Required for the DDC, SPI or USB busses.
 
+  reset-gpios:
+    maxItems: 1
+
   vcc-supply:
     description: >
       Main voltage regulator
@@ -49,10 +52,13 @@ unevaluatedProperties: false
 
 examples:
   - |
+    #include <dt-bindings/gpio/gpio.h>
+
     serial {
         gnss {
             compatible = "u-blox,neo-8";
             v-bckp-supply = <&gnss_v_bckp_reg>;
             vcc-supply = <&gnss_vcc_reg>;
+            reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
         };
     };

drivers/gnss/ubx.c

@@ -7,6 +7,7 @@
 
 #include <linux/errno.h>
 #include <linux/gnss.h>
+#include <linux/gpio/consumer.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -17,7 +18,6 @@
 #include "serial.h"
 
 struct ubx_data {
-	struct regulator *v_bckp;
 	struct regulator *vcc;
 };
 
@@ -66,6 +66,7 @@ static const struct gnss_serial_ops ubx_gserial_ops = {
 static int ubx_probe(struct serdev_device *serdev)
 {
 	struct gnss_serial *gserial;
+	struct gpio_desc *reset;
 	struct ubx_data *data;
 	int ret;
 
@@ -87,30 +88,23 @@ static int ubx_probe(struct serdev_device *serdev)
 		goto err_free_gserial;
 	}
 
-	data->v_bckp = devm_regulator_get_optional(&serdev->dev, "v-bckp");
-	if (IS_ERR(data->v_bckp)) {
-		ret = PTR_ERR(data->v_bckp);
-		if (ret == -ENODEV)
-			data->v_bckp = NULL;
-		else
-			goto err_free_gserial;
-	}
+	ret = devm_regulator_get_enable_optional(&serdev->dev, "v-bckp");
+	if (ret < 0 && ret != -ENODEV)
+		goto err_free_gserial;
 
-	if (data->v_bckp) {
-		ret = regulator_enable(data->v_bckp);
-		if (ret)
-			goto err_free_gserial;
+	/* Deassert reset */
+	reset = devm_gpiod_get_optional(&serdev->dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(reset)) {
+		ret = PTR_ERR(reset);
+		goto err_free_gserial;
 	}
 
 	ret = gnss_serial_register(gserial);
 	if (ret)
-		goto err_disable_v_bckp;
+		goto err_free_gserial;
 
 	return 0;
 
-err_disable_v_bckp:
-	if (data->v_bckp)
-		regulator_disable(data->v_bckp);
 err_free_gserial:
 	gnss_serial_free(gserial);
 
@@ -120,11 +114,8 @@ static int ubx_probe(struct serdev_device *serdev)
 static void ubx_remove(struct serdev_device *serdev)
 {
 	struct gnss_serial *gserial = serdev_device_get_drvdata(serdev);
-	struct ubx_data *data = gnss_serial_get_drvdata(gserial);
 
 	gnss_serial_deregister(gserial);
-	if (data->v_bckp)
-		regulator_disable(data->v_bckp);
 	gnss_serial_free(gserial);
 }