regulator: pickable ranges: don't always cache vsel

[ Upstream commit f4f4276f985a5aac7b310a4ed040b47e275e7591 ]

Some PMICs treat the vsel_reg same as apply-bit. Eg, when voltage range
is changed, the new voltage setting is not taking effect until the vsel
register is written.

Add a flag 'range_applied_by_vsel' to the regulator desc to indicate this
behaviour and to force the vsel value to be written to hardware if range
was changed, even if the old selector was same as the new one.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://msgid.link/r/ZktCpcGZdgHWuN_L@fedora
Signed-off-by: Mark Brown <broonie@kernel.org>
Stable-dep-of: 1ace99d7c7c4 ("regulator: tps6287x: Force writing VSEL bit")
Signed-off-by: Sasha Levin <sashal@kernel.org>

1 files changed, 30 insertions, 13 deletions

diff --git a/drivers/regulator/helpers.c b/drivers/regulator/helpers.c
index d49268336553..6e1ace660b8c 100644
--- a/drivers/regulator/helpers.c
+++ b/drivers/regulator/helpers.c
@@ -161,6 +161,32 @@ int regulator_get_voltage_sel_pickable_regmap(struct regulator_dev *rdev)
 }
 EXPORT_SYMBOL_GPL(regulator_get_voltage_sel_pickable_regmap);
 
+static int write_separate_vsel_and_range(struct regulator_dev *rdev,
+					 unsigned int sel, unsigned int range)
+{
+	bool range_updated;
+	int ret;
+
+	ret = regmap_update_bits_base(rdev->regmap, rdev->desc->vsel_range_reg,
+				      rdev->desc->vsel_range_mask,
+				      range, &range_updated, false, false);
+	if (ret)
+		return ret;
+
+	/*
+	 * Some PMICs treat the vsel_reg same as apply-bit. Force it to be
+	 * written if the range changed, even if the old selector was same as
+	 * the new one
+	 */
+	if (rdev->desc->range_applied_by_vsel && range_updated)
+		return regmap_write_bits(rdev->regmap,
+					rdev->desc->vsel_reg,
+					rdev->desc->vsel_mask, sel);
+
+	return regmap_update_bits(rdev->regmap, rdev->desc->vsel_reg,
+				  rdev->desc->vsel_mask, sel);
+}
+
 /**
  * regulator_set_voltage_sel_pickable_regmap - pickable range set_voltage_sel
  *
@@ -199,21 +225,12 @@ int regulator_set_voltage_sel_pickable_regmap(struct regulator_dev *rdev,
 	range = rdev->desc->linear_range_selectors_bitfield[i];
 	range <<= ffs(rdev->desc->vsel_range_mask) - 1;
 
-	if (rdev->desc->vsel_reg == rdev->desc->vsel_range_reg) {
-		ret = regmap_update_bits(rdev->regmap,
-					 rdev->desc->vsel_reg,
+	if (rdev->desc->vsel_reg == rdev->desc->vsel_range_reg)
+		ret = regmap_update_bits(rdev->regmap, rdev->desc->vsel_reg,
 					 rdev->desc->vsel_range_mask |
 					 rdev->desc->vsel_mask, sel | range);
-	} else {
-		ret = regmap_update_bits(rdev->regmap,
-					 rdev->desc->vsel_range_reg,
-					 rdev->desc->vsel_range_mask, range);
-		if (ret)
-			return ret;
-
-		ret = regmap_update_bits(rdev->regmap, rdev->desc->vsel_reg,
-				  rdev->desc->vsel_mask, sel);
-	}
+	else
+		ret = write_separate_vsel_and_range(rdev, sel, range);
 
 	if (ret)
 		return ret;