[PATCH v2] power: regulator: tps65941: Enable FPWM bits

[J, KEERTHY]

-----Original Message-----
From: Francis, Neha <n-francis at ti.com> 
Sent: Tuesday, April 21, 2026 1:52 PM
To: trini at konsulko.com; jh80.chung at samsung.com; peng.fan at nxp.com
Cc: J, KEERTHY <j-keerthy at ti.com>; Fujiwara, Takuma <t-fujiwara1 at ti.com>; u-boot at lists.denx.de; Kumar, Udit <u-kumar1 at ti.com>; Gujulan Elango, Hari Prasath <gehariprasath at ti.com>; Francis, Neha <n-francis at ti.com>
Subject: [PATCH v2] power: regulator: tps65941: Enable FPWM bits

Depending on the phase selection (single or multi), the FPWM bits configured forces the regulator to operate in PWM mode. In case of multi-phase selection, the FPWM_MP bits enforce the regulator to also operate in multi-phase. This fixes correct multi-phase operation.

While at this, correct incorrect macro alignment as well.

> FWIW Reviewed-by: Keerthy <j-keerthy at ti.com>

Fixes: 065a452ae6a1 ("power: regulator: tps65941: add regulator support")
Link: https://www.ti.com/lit/ds/symlink/tps6594-q1.pdf
Signed-off-by: Keerthy <j-keerthy at ti.com>
Signed-off-by: Takuma Fujiwara <t-fujiwara1 at ti.com>
Signed-off-by: Neha Malcom Francis <n-francis at ti.com>
---
Changes since v1:
https://lore.kernel.org/u-boot/20260129072857.1437272-1-n-francis@ti.com/
- alignment correction
- used existing macros instead of 12, 123 etc.

Tested on J721S2-EVM (same as v1, no logical changes)

https://gist.github.com/nehamalcom/a74fb2a3b59421d0e04693c7d244fdb4

Before the patch, the kernel TPS6594 regulator driver would warn about overcurrent on a buck, this was due to incorrect multi-phase configuration.
This patch resolves it.

 drivers/power/regulator/tps65941_regulator.c | 15 ++++++++++++---
 include/power/tps65941.h                     |  4 +++-
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/power/regulator/tps65941_regulator.c b/drivers/power/regulator/tps65941_regulator.c
index 2561d6f4c6c..209968b5718 100644
--- a/drivers/power/regulator/tps65941_regulator.c
+++ b/drivers/power/regulator/tps65941_regulator.c
@@ -63,13 +63,14 @@ static inline int tps65941_get_chip_id(struct udevice *dev)
 
 static int tps65941_buck_enable(struct udevice *dev, int op, bool *enable)  {
-	int ret;
+	int ret, idx;
 	unsigned int adr;
 	struct dm_regulator_uclass_plat *uc_pdata;
 
 	uc_pdata = dev_get_uclass_plat(dev);
 	adr = uc_pdata->ctrl_reg;
 
+	idx = dev->driver_data;
 	ret = pmic_reg_read(dev->parent, adr);
 	if (ret < 0)
 		return ret;
@@ -84,10 +85,18 @@ static int tps65941_buck_enable(struct udevice *dev, int op, bool *enable)
 
 		return 0;
 	} else if (op == PMIC_OP_SET) {
-		if (*enable)
+		if (*enable) {
 			ret |= TPS65941_BUCK_MODE_MASK;
-		else
+			/* Enable FPWM */
+			ret |= TPS65941_BUCK_FPWM_MASK;
+			/* If Multiphase enable FPWM_MP */
+			if (idx == TPS65941_BUCK_ID_12 ||
+			    idx == TPS65941_BUCK_ID_123 ||
+			    idx == TPS65941_BUCK_ID_1234)
+				ret |= TPS65941_BUCK_FPWM_MP_MASK;
+		} else {
 			ret &= ~TPS65941_BUCK_MODE_MASK;
+		}
 		ret = pmic_reg_write(dev->parent, adr, ret);
 		if (ret)
 			return ret;
diff --git a/include/power/tps65941.h b/include/power/tps65941.h index a026ec56958..78e48a15972 100644
--- a/include/power/tps65941.h
+++ b/include/power/tps65941.h
@@ -19,7 +19,9 @@
 #define TPS65941_BUCK_VOLT_MASK		0xFF
 #define TPS65941_BUCK_VOLT_MAX_HEX	0xFF
 #define TPS65941_BUCK_VOLT_MAX		3340000
-#define TPS65941_BUCK_MODE_MASK		0x1
+#define TPS65941_BUCK_MODE_MASK	0x1
+#define TPS65941_BUCK_FPWM_MASK	0x2
+#define TPS65941_BUCK_FPWM_MP_MASK	0x4
 
 #define TPS65941_LDO_VOLT_MASK		0x7E
 #define TPS65941_LDO_VOLT_MAX_HEX	0x3A
--
2.34.1