regulator: palmas: implement errata for ES1.0,ES2.0 and ES2.1

The device has the errata and sw need to implement the WAR for
proper functioning of the device.

The errata are:
1. SMPS- slew rate (TSTEP) is slower than expected
-----------------------------------------------
when output voltage target is close to previous one

IMPACT: The settling time is greater than specified slew rate in
register map and datasheet for voltage scaling of the SMPS.

DESCRIPTION: Measurement done on WCSP ES2.0, SMPS8, SMPS6, SMPS12
for TSTEP=0x02(5mV/us)
- step from VOUT= 0.5v to 1.65V ==>slew rate is around 5mV/us
- step from VOUT= 0.96v to 1.04V ==>slew rate is around 2.5mV/us
for TSTEP=0x03(2.5mV/us)
- step from VOUT= 0.5v to 1.65V ==>slew rate is around 2.5mV/us
- step from VOUT= 0.96v to 1.04V ==>slew rate is around 1.6mV/us

WORKAROUND: Adapt wait time using above value.

REVISION IMPACTED: ES1.0/ES2.0/ES2.1

2. LDO8_TRACKING: PD in tracking mode
-------------------------------------
IMPACT: Higher consumption and performance impact when LDO8 is set in
tracking mode and LDO is set to have its pull down enabled in OFF mode.

DESCRIPTION: When LDO8 is set in tracking mode and the LDO is set to have
its pull down enabled in OFF, the pull down is also enabled in ACTIVE mode.

WORKAROUND: In tracking mode, bit7 of LDO_PD_CTRL1 register must be set to 0.
When LDO8 is disabled, to have the pull down, bit7 of LDO_PD_CTRL1 register must
then be set to 1.
 In LDO8 regulation mode, behavior is the same as the other LDOs.

REVISION IMPACTED: ES 2.1 ES2.0 ES1.0

bug 1228386
bug 1195226

Change-Id: Ib19a21cb722b1bc07d93a0cf866c134672ef8735
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-on: http://git-master/r/199132
Reviewed-by: Automatic_Commit_Validation_User

1 files changed, 35 insertions, 23 deletions

diff --git a/drivers/regulator/palmas-regulator.c b/drivers/regulator/palmas-regulator.c
index 7ac6fdb20639..5c233bfef779 100644
--- a/drivers/regulator/palmas-regulator.c
+++ b/drivers/regulator/palmas-regulator.c
@@ -457,7 +457,9 @@ static int palma_smps_set_voltage_smps_time_sel(struct regulator_dev *rdev,
 	unsigned int ramp_delay = pmic->ramp_delay[id];
 
 	/* ES2.1, have the 1.5X slower slew rate than configured */
-	ramp_delay = (ramp_delay * 15)/10;
+	if (palmas_is_es_version_or_less(pmic->palmas, 2, 1))
+		ramp_delay = (ramp_delay * 15)/10;
+
 	if (!ramp_delay)
 		return 0;
 
@@ -1060,20 +1062,25 @@ static void palmas_enable_ldo8_track(struct palmas *palmas)
 	}
 
 	/*
+	 * Errata ES1.0, 2,0 and 2.1
 	 * When Tracking is enbled, it need to disable Pull-Down for LDO8 and
 	 * when tracking is disabled, SW has to enabe Pull-Down.
 	 */
-	addr = PALMAS_LDO_PD_CTRL1;
-	ret = palmas_ldo_read(palmas, addr, &reg);
-	if (ret < 0) {
-		dev_err(palmas->dev, "Error in reading pulldown control reg\n");
-		return;
-	}
-	reg &= ~PALMAS_LDO_PD_CTRL1_LDO8;
-	ret = palmas_ldo_write(palmas, addr, reg);
-	if (ret < 0) {
-		dev_err(palmas->dev, "Error in setting pulldown control reg\n");
-		return;
+	if (palmas_is_es_version_or_less(palmas, 2, 1)) {
+		addr = PALMAS_LDO_PD_CTRL1;
+		ret = palmas_ldo_read(palmas, addr, &reg);
+		if (ret < 0) {
+			dev_err(palmas->dev,
+				"Error in reading pulldown control reg\n");
+			return;
+		}
+		reg &= ~PALMAS_LDO_PD_CTRL1_LDO8;
+		ret = palmas_ldo_write(palmas, addr, reg);
+		if (ret < 0) {
+			dev_err(palmas->dev,
+				"Error in setting pulldown control reg\n");
+			return;
+		}
 	}
 
 	return;
@@ -1119,20 +1126,25 @@ static void palmas_disable_ldo8_track(struct palmas *palmas)
 	}
 
 	/*
+	 * Errata ES1.0, 2,0 and 2.1
 	 * When Tracking is enbled, it need to disable Pull-Down for LDO8 and
 	 * when tracking is disabled, SW has to enabe Pull-Down.
 	 */
-	addr = PALMAS_LDO_PD_CTRL1;
-	ret = palmas_ldo_read(palmas, addr, &reg);
-	if (ret < 0) {
-		dev_err(palmas->dev, "Error in reading pulldown control reg\n");
-		return;
-	}
-	reg |= PALMAS_LDO_PD_CTRL1_LDO8;
-	ret = palmas_ldo_write(palmas, addr, reg);
-	if (ret < 0) {
-		dev_err(palmas->dev, "Error in setting pulldown control reg\n");
-		return;
+	if (palmas_is_es_version_or_less(palmas, 2, 1)) {
+		addr = PALMAS_LDO_PD_CTRL1;
+		ret = palmas_ldo_read(palmas, addr, &reg);
+		if (ret < 0) {
+			dev_err(palmas->dev,
+				"Error in reading pulldown control reg\n");
+			return;
+		}
+		reg |= PALMAS_LDO_PD_CTRL1_LDO8;
+		ret = palmas_ldo_write(palmas, addr, reg);
+		if (ret < 0) {
+			dev_err(palmas->dev,
+				"Error in setting pulldown control reg\n");
+			return;
+		}
 	}
 
 	return;