backlight: mp3309c: Make use of device properties

Convert the module to be property provider agnostic and allow
it to be used on non-OF platforms.

Add mod_devicetable.h include.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Flavio Suligoi <f.suligoi@asem.it>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20240208184313.2224579-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Lee Jones <lee@kernel.org>

drivers/video/backlight/mp3309c.c

@@ -15,6 +15,8 @@
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
+#include <linux/property.h>
 #include <linux/pwm.h>
 #include <linux/regmap.h>
 
@@ -199,18 +201,15 @@ static const struct backlight_ops mp3309c_bl_ops = {
 	.update_status = mp3309c_bl_update_status,
 };
 
-static int pm3309c_parse_dt_node(struct mp3309c_chip *chip,
-				 struct mp3309c_platform_data *pdata)
+static int mp3309c_parse_fwnode(struct mp3309c_chip *chip,
+				struct mp3309c_platform_data *pdata)
 {
-	struct device_node *node = chip->dev->of_node;
-	struct property *prop_pwms;
-	struct property *prop_levels = NULL;
-	int length = 0;
 	int ret, i;
 	unsigned int num_levels, tmp_value;
+	struct device *dev = chip->dev;
 
-	if (!node) {
-		dev_err(chip->dev, "failed to get DT node\n");
+	if (!dev_fwnode(dev)) {
+		dev_err(dev, "failed to get firmware node\n");
 		return -ENODEV;
 	}
 
@@ -224,8 +223,7 @@ static int pm3309c_parse_dt_node(struct mp3309c_chip *chip,
 	 * found in the backlight node, the mode switches to PWM mode.
 	 */
 	pdata->dimming_mode = DIMMING_ANALOG_I2C;
-	prop_pwms = of_find_property(node, "pwms", &length);
-	if (prop_pwms) {
+	if (device_property_present(dev, "pwms")) {
 		chip->pwmd = devm_pwm_get(chip->dev, NULL);
 		if (IS_ERR(chip->pwmd))
 			return dev_err_probe(chip->dev, PTR_ERR(chip->pwmd),
@@ -257,11 +255,9 @@ static int pm3309c_parse_dt_node(struct mp3309c_chip *chip,
 		/*
 		 * PWM control mode: check for brightness level in DT
 		 */
-		prop_levels = of_find_property(node, "brightness-levels",
-					       &length);
-		if (prop_levels) {
+		if (device_property_present(dev, "brightness-levels")) {
 			/* Read brightness levels from DT */
-			num_levels = length / sizeof(u32);
+			num_levels = device_property_count_u32(dev, "brightness-levels");
 			if (num_levels < 2)
 				return -EINVAL;
 		} else {
@@ -275,10 +271,9 @@ static int pm3309c_parse_dt_node(struct mp3309c_chip *chip,
 				     sizeof(*pdata->levels), GFP_KERNEL);
 	if (!pdata->levels)
 		return -ENOMEM;
-	if (prop_levels) {
-		ret = of_property_read_u32_array(node, "brightness-levels",
-						 pdata->levels,
-						 num_levels);
+	if (device_property_present(dev, "brightness-levels")) {
+		ret = device_property_read_u32_array(dev, "brightness-levels",
+						     pdata->levels, num_levels);
 		if (ret < 0)
 			return ret;
 	} else {
@@ -288,8 +283,7 @@ static int pm3309c_parse_dt_node(struct mp3309c_chip *chip,
 
 	pdata->max_brightness = num_levels - 1;
 
-	ret = of_property_read_u32(node, "default-brightness",
-				   &pdata->default_brightness);
+	ret = device_property_read_u32(dev, "default-brightness", &pdata->default_brightness);
 	if (ret)
 		pdata->default_brightness = pdata->max_brightness;
 	if (pdata->default_brightness > pdata->max_brightness) {
@@ -310,8 +304,8 @@ static int pm3309c_parse_dt_node(struct mp3309c_chip *chip,
 	 * If missing, the default value for OVP is 35.5V
 	 */
 	pdata->over_voltage_protection = REG_I2C_1_OVP1;
-	if (!of_property_read_u32(node, "mps,overvoltage-protection-microvolt",
-				  &tmp_value)) {
+	ret = device_property_read_u32(dev, "mps,overvoltage-protection-microvolt", &tmp_value);
+	if (!ret) {
 		switch (tmp_value) {
 		case 13500000:
 			pdata->over_voltage_protection = 0x00;
@@ -328,9 +322,7 @@ static int pm3309c_parse_dt_node(struct mp3309c_chip *chip,
 	}
 
 	/* Synchronous (default) and non-synchronous mode */
-	pdata->sync_mode = true;
-	if (of_property_read_bool(node, "mps,no-sync-mode"))
-		pdata->sync_mode = false;
+	pdata->sync_mode = !device_property_read_bool(dev, "mps,no-sync-mode");
 
 	return 0;
 }
@@ -366,7 +358,7 @@ static int mp3309c_probe(struct i2c_client *client)
 		if (!pdata)
 			return -ENOMEM;
 
-		ret = pm3309c_parse_dt_node(chip, pdata);
+		ret = mp3309c_parse_fwnode(chip, pdata);
 		if (ret)
 			return ret;
 	}