regulator: max8997: Convert to GPIO descriptors

This rewrites the max8997 regulator driver to fetch the dvs
regulators as descriptors. This will likely mostly come from
the device tree since there are no in-tree users of the platform
data, but supplying GPIO descriptor tables from board files is
also possible if needed.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://msgid.link/r/20240220-descriptors-regulators-v1-4-097f608694be@linaro.org
Acked-by: Lee Jones <lee@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Linus Walleij

drivers/regulator/max8997-regulator.c

@@ -9,8 +9,7 @@
 
 #include <linux/bug.h>
 #include <linux/err.h>
-#include <linux/gpio.h>
-#include <linux/of_gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
@@ -32,7 +31,7 @@ struct max8997_data {
 	u8 buck1_vol[8];
 	u8 buck2_vol[8];
 	u8 buck5_vol[8];
-	int buck125_gpios[3];
+	struct gpio_desc *buck125_gpiods[3];
 	int buck125_gpioindex;
 	bool ignore_gpiodvs_side_effect;
 
@@ -52,9 +51,9 @@ static inline void max8997_set_gpio(struct max8997_data *max8997)
 	int set2 = ((max8997->buck125_gpioindex) >> 1) & 0x1;
 	int set1 = ((max8997->buck125_gpioindex) >> 2) & 0x1;
 
-	gpio_set_value(max8997->buck125_gpios[0], set1);
-	gpio_set_value(max8997->buck125_gpios[1], set2);
-	gpio_set_value(max8997->buck125_gpios[2], set3);
+	gpiod_set_value(max8997->buck125_gpiods[0], set1);
+	gpiod_set_value(max8997->buck125_gpiods[1], set2);
+	gpiod_set_value(max8997->buck125_gpiods[2], set3);
 }
 
 struct voltage_map_desc {
@@ -873,31 +872,13 @@ static struct regulator_desc regulators[] = {
 };
 
 #ifdef CONFIG_OF
-static int max8997_pmic_dt_parse_dvs_gpio(struct platform_device *pdev,
-			struct max8997_platform_data *pdata,
-			struct device_node *pmic_np)
-{
-	int i, gpio;
-
-	for (i = 0; i < 3; i++) {
-		gpio = of_get_named_gpio(pmic_np,
-					"max8997,pmic-buck125-dvs-gpios", i);
-		if (!gpio_is_valid(gpio)) {
-			dev_err(&pdev->dev, "invalid gpio[%d]: %d\n", i, gpio);
-			return -EINVAL;
-		}
-		pdata->buck125_gpios[i] = gpio;
-	}
-	return 0;
-}
-
 static int max8997_pmic_dt_parse_pdata(struct platform_device *pdev,
 					struct max8997_platform_data *pdata)
 {
 	struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 	struct device_node *pmic_np, *regulators_np, *reg_np;
 	struct max8997_regulator_data *rdata;
-	unsigned int i, dvs_voltage_nr = 1, ret;
+	unsigned int i, dvs_voltage_nr = 1;
 
 	pmic_np = iodev->dev->of_node;
 	if (!pmic_np) {
@@ -949,10 +930,6 @@ static int max8997_pmic_dt_parse_pdata(struct platform_device *pdev,
 
 	if (pdata->buck1_gpiodvs || pdata->buck2_gpiodvs ||
 						pdata->buck5_gpiodvs) {
-		ret = max8997_pmic_dt_parse_dvs_gpio(pdev, pdata, pmic_np);
-		if (ret)
-			return -EINVAL;
-
 		if (of_property_read_u32(pmic_np,
 				"max8997,pmic-buck125-default-dvs-idx",
 				&pdata->buck125_default_idx)) {
@@ -1039,7 +1016,6 @@ static int max8997_pmic_probe(struct platform_device *pdev)
 	max8997->buck1_gpiodvs = pdata->buck1_gpiodvs;
 	max8997->buck2_gpiodvs = pdata->buck2_gpiodvs;
 	max8997->buck5_gpiodvs = pdata->buck5_gpiodvs;
-	memcpy(max8997->buck125_gpios, pdata->buck125_gpios, sizeof(int) * 3);
 	max8997->ignore_gpiodvs_side_effect = pdata->ignore_gpiodvs_side_effect;
 
 	nr_dvs = (pdata->buck1_gpiodvs || pdata->buck2_gpiodvs ||
@@ -1110,38 +1086,27 @@ static int max8997_pmic_probe(struct platform_device *pdev)
 	 */
 	if (pdata->buck1_gpiodvs || pdata->buck2_gpiodvs ||
 			pdata->buck5_gpiodvs) {
+		const char *gpio_names[3] = {"MAX8997 SET1", "MAX8997 SET2", "MAX8997 SET3"};
 
-		if (!gpio_is_valid(pdata->buck125_gpios[0]) ||
-				!gpio_is_valid(pdata->buck125_gpios[1]) ||
-				!gpio_is_valid(pdata->buck125_gpios[2])) {
-			dev_err(&pdev->dev, "GPIO NOT VALID\n");
-			return -EINVAL;
-		}
+		for (i = 0; i < 3; i++) {
+			enum gpiod_flags flags;
 
-		ret = devm_gpio_request(&pdev->dev, pdata->buck125_gpios[0],
-					"MAX8997 SET1");
-		if (ret)
-			return ret;
-
-		ret = devm_gpio_request(&pdev->dev, pdata->buck125_gpios[1],
-					"MAX8997 SET2");
-		if (ret)
-			return ret;
-
-		ret = devm_gpio_request(&pdev->dev, pdata->buck125_gpios[2],
-				"MAX8997 SET3");
-		if (ret)
-			return ret;
-
-		gpio_direction_output(pdata->buck125_gpios[0],
-				(max8997->buck125_gpioindex >> 2)
-				& 0x1); /* SET1 */
-		gpio_direction_output(pdata->buck125_gpios[1],
-				(max8997->buck125_gpioindex >> 1)
-				& 0x1); /* SET2 */
-		gpio_direction_output(pdata->buck125_gpios[2],
-				(max8997->buck125_gpioindex >> 0)
-				& 0x1); /* SET3 */
+			if (max8997->buck125_gpioindex & BIT(2 - i))
+				flags = GPIOD_OUT_HIGH;
+			else
+				flags = GPIOD_OUT_LOW;
+
+			max8997->buck125_gpiods[i] = devm_gpiod_get_index(iodev->dev,
+									  "max8997,pmic-buck125-dvs",
+									  i,
+									  flags);
+			if (IS_ERR(max8997->buck125_gpiods[i])) {
+				ret = PTR_ERR(max8997->buck125_gpiods[i]);
+				return dev_err_probe(iodev->dev, ret, "cant get GPIO %d (%d)\n",
+						     i, ret);
+			}
+			gpiod_set_consumer_name(max8997->buck125_gpiods[i], gpio_names[i]);
+		}
 	}
 
 	/* DVS-GPIO disabled */

include/linux/mfd/max8997.h

@@ -178,7 +178,6 @@ struct max8997_platform_data {
 	 *
 	 */
 	bool ignore_gpiodvs_side_effect;
-	int buck125_gpios[3]; /* GPIO of [0]SET1, [1]SET2, [2]SET3 */
 	int buck125_default_idx; /* Default value of SET1, 2, 3 */
 	unsigned int buck1_voltage[8]; /* buckx_voltage in uV */
 	bool buck1_gpiodvs;