regulator: lp87565: Add 4-phase lp87561 regulator support

The LP8756x family has a single output 4-phase regulator
configuration. Add support for the same. The control
lies in the master buck which is buck0 for 4-phase
configuration. Enable/disable/voltage set happen via
buck0 registers.

Data Sheet: https://www.ti.com/lit/ds/symlink/lp87561-q1.pdf

Signed-off-by: Keerthy <j-keerthy@ti.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/regulator/lp87565-regulator.c

@@ -153,6 +153,12 @@ static const struct lp87565_regulator regulators[] = {
 			  LP87565_REG_BUCK2_CTRL_1,
 			  LP87565_BUCK_CTRL_1_EN, 3230,
 			  buck0_1_2_3_ranges, LP87565_REG_BUCK2_CTRL_2),
+	LP87565_REGULATOR("BUCK3210", LP87565_BUCK_3210, "buck3210",
+			  lp87565_buck_ops, 256, LP87565_REG_BUCK0_VOUT,
+			  LP87565_BUCK_VSET, LP87565_REG_BUCK0_CTRL_1,
+			  LP87565_BUCK_CTRL_1_EN |
+			  LP87565_BUCK_CTRL_1_FPWM_MP_0_2, 3230,
+			  buck0_1_2_3_ranges, LP87565_REG_BUCK0_CTRL_2),
 };
 
 static int lp87565_regulator_probe(struct platform_device *pdev)
@@ -169,9 +175,18 @@ static int lp87565_regulator_probe(struct platform_device *pdev)
 	config.driver_data = lp87565;
 	config.regmap = lp87565->regmap;
 
-	if (lp87565->dev_type == LP87565_DEVICE_TYPE_LP87565_Q1) {
+	switch (lp87565->dev_type) {
+	case LP87565_DEVICE_TYPE_LP87565_Q1:
 		min_idx = LP87565_BUCK_10;
 		max_idx = LP87565_BUCK_23;
+		break;
+	case LP87565_DEVICE_TYPE_LP87561_Q1:
+		min_idx = LP87565_BUCK_3210;
+		max_idx = LP87565_BUCK_3210;
+	default:
+		dev_err(lp87565->dev, "Invalid lp config %d\n",
+			lp87565->dev_type);
+		return -EINVAL;
 	}
 
 	for (i = min_idx; i <= max_idx; i++) {