drivers: regulator: pca9420: refactor mode handling

- Similar to what was done for other parts of the driver, remove any
  register specification from Devicetree (modesel-reg/mask)
- Keep all the information in the driver, and define modes as "numbers",
  e.g. PCA9420_MODE0: 0, PCA9420_MODE1: 1, etc.
- Bindings provide IC defaults now (all modes allowed 0/1/2/3 and
  initial mode set to 0).
- When mode is controlled via the MODESEL0/1 pins (ie directly by an iMX
  MCU using the dedicated PMIC_MODE0/1 pins), the driver will not allow
  to select a mode (it is not possible). This mode is now enabled by
  setting `nxp,enable-modesel-pins` in Devicetree. When enabled, all the
  allowed modes are configured to be selectable via pins. When disabled,
  mode can be set via I2C (using TOP_CNTL3 MODE0/1_I2C fields)

Signed-off-by: Gerard Marull-Paretas <[email protected]>

Author: gmarull

boards/arm/mimxrt595_evk/mimxrt595_evk_cm33.dts

@@ -159,28 +159,10 @@ arduino_serial: &flexcomm12 {
 	pinctrl-names = "default";
 
 	pca9420: pca9420@61 {
-		reg = <0x61>;
 		compatible = "nxp,pca9420";
-		/*
-		 * This mode-reg setting will permit mode control by
-		 * pins, a feature of the PCA9240. If mode control via
-		 * I2C is desired, the following settings
-		 * should be used:
-		 * regulator-initial-mode = <PCA9420_MODECFG0_I2C>;
-		 * regulator-allowed-modes = <PCA9420_MODECFG0_I2C>,
-		 *			<PCA9420_MODECFG1_I2C>,
-		 *			<PCA9420_MODECFG2_I2C>,
-		 *			<PCA9420_MODECFG3_I2C>;
-		 * modesel-reg = <PCA9420_TOP_CNTL3>;
-		 * modesel-mask = <PCA9420_TOP_CNTL3_MODE_I2C_MASK>;
-		 */
-		regulator-allowed-modes = <PCA9420_MODECFG0_PIN>,
-					<PCA9420_MODECFG1_PIN>,
-					<PCA9420_MODECFG2_PIN>,
-					<PCA9420_MODECFG3_PIN>;
-		regulator-initial-mode = <PCA9420_MODECFG0_PIN>;
-		modesel-reg = <PCA9420_MODECFG_0_0>;
-		modesel-mask = <PCA9420_MODECFG_0_MODE_CTRL_SEL_MASK>;
+		reg = <0x61>;
+		nxp,enable-modesel-pins;
+
 		pca9420_sw1: BUCK1 {
 			regulator-min-microvolt = <500000>;
 			regulator-max-microvolt = <1800000>;

boards/arm/mimxrt685_evk/mimxrt685_evk_cm33.dts

@@ -229,28 +229,10 @@ i2s1: &flexcomm3 {
 	pinctrl-names = "default";
 
 	pca9420: pca9420@61 {
-		reg = <0x61>;
 		compatible = "nxp,pca9420";
-		/*
-		 * This mode-reg setting will permit mode control by
-		 * pins, a feature of the PCA9240. If mode control via
-		 * I2C is desired, the following settings
-		 * should be used:
-		 * regulator-initial-mode = <PCA9420_MODECFG0_I2C>;
-		 * regulator-allowed-modes = <PCA9420_MODECFG0_I2C>,
-		 *			<PCA9420_MODECFG1_I2C>,
-		 *			<PCA9420_MODECFG2_I2C>,
-		 *			<PCA9420_MODECFG3_I2C>;
-		 * modesel-reg = <PCA9420_TOP_CNTL3>;
-		 * modesel-mask = <PCA9420_TOP_CNTL3_MODE_I2C_MASK>;
-		 */
-		regulator-allowed-modes = <PCA9420_MODECFG0_PIN>,
-					<PCA9420_MODECFG1_PIN>,
-					<PCA9420_MODECFG2_PIN>,
-					<PCA9420_MODECFG3_PIN>;
-		regulator-initial-mode = <PCA9420_MODECFG0_PIN>;
-		modesel-reg = <PCA9420_MODECFG_0_0>;
-		modesel-mask = <PCA9420_MODECFG_0_MODE_CTRL_SEL_MASK>;
+		reg = <0x61>;
+		nxp,enable-modesel-pins;
+
 		BUCK1 {
 			regulator-min-microvolt = <500000>;
 			regulator-max-microvolt = <1800000>;