regulator: palma: add ramp delay support through regulator constraints

Currently Palma regulator driver support the ramp delay
through rail specific platform data.

As regulator framework support the configuration of ramp
delay through regulator constraint, using the framework
method and removing the platform specific data approach.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by: Graeme Gregory <gg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/regulator/palmas-regulator.c

@@ -187,6 +187,8 @@ static const struct regs_info palmas_regs_info[] = {
 	},
 };
 
+static unsigned int palmas_smps_ramp_delay[4] = {0, 10000, 5000, 2500};
+
 #define SMPS_CTRL_MODE_OFF		0x00
 #define SMPS_CTRL_MODE_ON		0x01
 #define SMPS_CTRL_MODE_ECO		0x02
@@ -397,6 +399,56 @@ static int palmas_map_voltage_smps(struct regulator_dev *rdev,
 	return ret;
 }
 
+static int palma_smps_set_voltage_smps_time_sel(struct regulator_dev *rdev,
+	unsigned int old_selector, unsigned int new_selector)
+{
+	struct palmas_pmic *pmic = rdev_get_drvdata(rdev);
+	int id = rdev_get_id(rdev);
+	int old_uv, new_uv;
+	unsigned int ramp_delay = pmic->ramp_delay[id];
+
+	if (!ramp_delay)
+		return 0;
+
+	old_uv = palmas_list_voltage_smps(rdev, old_selector);
+	if (old_uv < 0)
+		return old_uv;
+
+	new_uv = palmas_list_voltage_smps(rdev, new_selector);
+	if (new_uv < 0)
+		return new_uv;
+
+	return DIV_ROUND_UP(abs(old_uv - new_uv), ramp_delay);
+}
+
+static int palmas_smps_set_ramp_delay(struct regulator_dev *rdev,
+		 int ramp_delay)
+{
+	struct palmas_pmic *pmic = rdev_get_drvdata(rdev);
+	int id = rdev_get_id(rdev);
+	unsigned int reg = 0;
+	unsigned int addr = palmas_regs_info[id].tstep_addr;
+	int ret;
+
+	if (ramp_delay <= 0)
+		reg = 0;
+	else if (ramp_delay < 2500)
+		reg = 3;
+	else if (ramp_delay < 5000)
+		reg = 2;
+	else
+		reg = 1;
+
+	ret = palmas_smps_write(pmic->palmas, addr, reg);
+	if (ret < 0) {
+		dev_err(pmic->palmas->dev, "TSTEP write failed: %d\n", ret);
+		return ret;
+	}
+
+	pmic->ramp_delay[id] = palmas_smps_ramp_delay[reg];
+	return ret;
+}
+
 static struct regulator_ops palmas_ops_smps = {
 	.is_enabled		= palmas_is_enabled_smps,
 	.enable			= palmas_enable_smps,
@@ -407,6 +459,8 @@ static struct regulator_ops palmas_ops_smps = {
 	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
 	.list_voltage		= palmas_list_voltage_smps,
 	.map_voltage		= palmas_map_voltage_smps,
+	.set_voltage_time_sel	= palma_smps_set_voltage_smps_time_sel,
+	.set_ramp_delay		= palmas_smps_set_ramp_delay,
 };
 
 static struct regulator_ops palmas_ops_smps10 = {
@@ -495,16 +549,6 @@ static int palmas_smps_init(struct palmas *palmas, int id,
 	if (ret)
 		return ret;
 
-	if (palmas_regs_info[id].tstep_addr && reg_init->tstep) {
-		addr = palmas_regs_info[id].tstep_addr;
-
-		reg = reg_init->tstep & PALMAS_SMPS12_TSTEP_TSTEP_MASK;
-
-		ret = palmas_smps_write(palmas, addr, reg);
-		if (ret)
-			return ret;
-	}
-
 	if (palmas_regs_info[id].vsel_addr && reg_init->vsel) {
 		addr = palmas_regs_info[id].vsel_addr;
 
@@ -686,11 +730,6 @@ static void palmas_dt_to_pdata(struct device *dev,
 		if (!ret)
 			pdata->reg_init[idx]->mode_sleep = prop;
 
-		ret = of_property_read_u32(palmas_matches[idx].of_node,
-				"ti,tstep", &prop);
-		if (!ret)
-			pdata->reg_init[idx]->tstep = prop;
-
 		ret = of_property_read_bool(palmas_matches[idx].of_node,
 					    "ti,smps-range");
 		if (ret)
@@ -752,6 +791,7 @@ static int palmas_regulators_probe(struct platform_device *pdev)
 	config.driver_data = pmic;
 
 	for (id = 0; id < PALMAS_REG_LDO1; id++) {
+		bool ramp_delay_support = false;
 
 		/*
 		 * Miss out regulators which are not available due
@@ -762,19 +802,42 @@ static int palmas_regulators_probe(struct platform_device *pdev)
 		case PALMAS_REG_SMPS3:
 			if (pmic->smps123)
 				continue;
+			if (id == PALMAS_REG_SMPS12)
+				ramp_delay_support = true;
 			break;
 		case PALMAS_REG_SMPS123:
 			if (!pmic->smps123)
 				continue;
+			ramp_delay_support = true;
 			break;
 		case PALMAS_REG_SMPS45:
 		case PALMAS_REG_SMPS7:
 			if (pmic->smps457)
 				continue;
+			if (id == PALMAS_REG_SMPS45)
+				ramp_delay_support = true;
 			break;
 		case PALMAS_REG_SMPS457:
 			if (!pmic->smps457)
 				continue;
+			ramp_delay_support = true;
+			break;
+		}
+
+		if ((id == PALMAS_REG_SMPS6) && (id == PALMAS_REG_SMPS8))
+			ramp_delay_support = true;
+
+		if (ramp_delay_support) {
+			addr = palmas_regs_info[id].tstep_addr;
+			ret = palmas_smps_read(pmic->palmas, addr, &reg);
+			if (ret < 0) {
+				dev_err(&pdev->dev,
+					"reading TSTEP reg failed: %d\n", ret);
+				goto err_unregister_regulator;
+			}
+			pmic->desc[id].ramp_delay =
+					palmas_smps_ramp_delay[reg & 0x3];
+			pmic->ramp_delay[id] = pmic->desc[id].ramp_delay;
 		}
 
 		/* Initialise sleep/init values from platform data */

include/linux/mfd/palmas.h

@@ -109,19 +109,6 @@ struct palmas_reg_init {
 	 */
 	int mode_sleep;
 
-	/* tstep is the timestep loaded to the TSTEP register
-	 *
-	 * For SMPS
-	 *
-	 * 0: Jump (no slope control)
-	 * 1: 10mV/us
-	 * 2: 5mV/us
-	 * 3: 2.5mV/us
-	 *
-	 * For LDO unused
-	 */
-	int tstep;
-
 	/* voltage_sel is the bitfield loaded onto the SMPSX_VOLTAGE
 	 * register. Set this is the default voltage set in OTP needs
 	 * to be overridden.
@@ -339,6 +326,7 @@ struct palmas_pmic {
 	int smps457;
 
 	int range[PALMAS_REG_SMPS10];
+	unsigned int ramp_delay[PALMAS_REG_SMPS10];
 };
 
 struct palmas_resource {