* [PATCH] regulator: pca9450: Support regulator-off-in-suspend
@ 2026-07-24 20:13 Fabio Estevam
2026-07-28 18:18 ` Mark Brown
0 siblings, 1 reply; 3+ messages in thread
From: Fabio Estevam @ 2026-07-24 20:13 UTC (permalink / raw)
To: broonie; +Cc: linux-kernel, imx, Fabio Estevam
From: Fabio Estevam <festevam@nabladev.com>
The PCA9450 uses each regulator's ENMODE field to control whether the
regulator remains enabled when the PMIC transitions from RUN to STANDBY
mode.
The driver does not currently implement set_suspend_disable(), so a
regulator configured with regulator-off-in-suspend remains enabled
during system suspend.
Implement set_suspend_disable() for the buck regulators and LDO3-LDO5
by programming ENMODE to 10b. This keeps the regulator enabled in RUN
mode, turns it off when PMIC_STBY_REQ is asserted, and enables it again
when the PMIC returns to RUN mode.
Keep LDO1 and LDO2 on regulator operations without
set_suspend_disable(), because these regulators supply the SNVS domain
and must remain enabled in STANDBY mode.
Measured on a custom i.MX8MP board, turning off NVCC_SD2 (LDO5) during
system suspend reduced power consumption by approximately 64 mW.
Signed-off-by: Fabio Estevam <festevam@nabladev.com>
---
drivers/regulator/pca9450-regulator.c | 43 +++++++++++++++++++++++----
include/linux/regulator/pca9450.h | 3 ++
2 files changed, 40 insertions(+), 6 deletions(-)
diff --git a/drivers/regulator/pca9450-regulator.c b/drivers/regulator/pca9450-regulator.c
index c41db70fa052..13082585140f 100644
--- a/drivers/regulator/pca9450-regulator.c
+++ b/drivers/regulator/pca9450-regulator.c
@@ -77,6 +77,24 @@ static const unsigned int pca9450_dvs_buck_ramp_table[] = {
25000, 12500, 6250, 3125
};
+/*
+ * ENMODE = 10b keeps the regulator enabled in RUN mode and disables it
+ * while PMIC_STBY_REQ is asserted.
+ */
+static int pca9450_buck_set_suspend_disable(struct regulator_dev *rdev)
+{
+ return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+ rdev->desc->enable_mask,
+ BUCK_ENMODE_ONREQ_STBYREQ);
+}
+
+static int pca9450_ldo_set_suspend_disable(struct regulator_dev *rdev)
+{
+ return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+ rdev->desc->enable_mask,
+ LDO_ENMODE_ONREQ_STBYREQ);
+}
+
static const struct regulator_ops pca9450_dvs_buck_regulator_ops = {
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
@@ -88,6 +106,7 @@ static const struct regulator_ops pca9450_dvs_buck_regulator_ops = {
.set_ramp_delay = regulator_set_ramp_delay_regmap,
.set_mode = pca9450_buck_set_mode,
.get_mode = pca9450_buck_get_mode,
+ .set_suspend_disable = pca9450_buck_set_suspend_disable,
};
static const struct regulator_ops pca9450_buck_regulator_ops = {
@@ -100,6 +119,7 @@ static const struct regulator_ops pca9450_buck_regulator_ops = {
.set_voltage_time_sel = regulator_set_voltage_time_sel,
.set_mode = pca9450_buck_set_mode,
.get_mode = pca9450_buck_get_mode,
+ .set_suspend_disable = pca9450_buck_set_suspend_disable,
};
static const struct regulator_ops pca9450_ldo_regulator_ops = {
@@ -111,6 +131,16 @@ static const struct regulator_ops pca9450_ldo_regulator_ops = {
.get_voltage_sel = regulator_get_voltage_sel_regmap,
};
+static const struct regulator_ops pca9450_ldo_suspend_regulator_ops = {
+ .enable = regulator_enable_regmap,
+ .disable = regulator_disable_regmap,
+ .is_enabled = regulator_is_enabled_regmap,
+ .list_voltage = regulator_list_voltage_linear_range,
+ .set_voltage_sel = regulator_set_voltage_sel_regmap,
+ .get_voltage_sel = regulator_get_voltage_sel_regmap,
+ .set_suspend_disable = pca9450_ldo_set_suspend_disable,
+};
+
static unsigned int pca9450_ldo5_get_reg_voltage_sel(struct regulator_dev *rdev)
{
struct pca9450 *pca9450 = rdev_get_drvdata(rdev);
@@ -164,6 +194,7 @@ static const struct regulator_ops pca9450_ldo5_regulator_ops = {
.list_voltage = regulator_list_voltage_linear_range,
.set_voltage_sel = pca9450_ldo5_set_voltage_sel_regmap,
.get_voltage_sel = pca9450_ldo5_get_voltage_sel_regmap,
+ .set_suspend_disable = pca9450_ldo_set_suspend_disable,
};
/*
@@ -575,7 +606,7 @@ static struct pca9450_regulator_desc pca9450a_regulators[] = {
.of_match = of_match_ptr("LDO3"),
.regulators_node = of_match_ptr("regulators"),
.id = PCA9450_LDO3,
- .ops = &pca9450_ldo_regulator_ops,
+ .ops = &pca9450_ldo_suspend_regulator_ops,
.type = REGULATOR_VOLTAGE,
.n_voltages = PCA9450_LDO3_VOLTAGE_NUM,
.linear_ranges = pca9450_ldo34_volts,
@@ -594,7 +625,7 @@ static struct pca9450_regulator_desc pca9450a_regulators[] = {
.of_match = of_match_ptr("LDO4"),
.regulators_node = of_match_ptr("regulators"),
.id = PCA9450_LDO4,
- .ops = &pca9450_ldo_regulator_ops,
+ .ops = &pca9450_ldo_suspend_regulator_ops,
.type = REGULATOR_VOLTAGE,
.n_voltages = PCA9450_LDO4_VOLTAGE_NUM,
.linear_ranges = pca9450_ldo34_volts,
@@ -820,7 +851,7 @@ static struct pca9450_regulator_desc pca9450bc_regulators[] = {
.of_match = of_match_ptr("LDO3"),
.regulators_node = of_match_ptr("regulators"),
.id = PCA9450_LDO3,
- .ops = &pca9450_ldo_regulator_ops,
+ .ops = &pca9450_ldo_suspend_regulator_ops,
.type = REGULATOR_VOLTAGE,
.n_voltages = PCA9450_LDO3_VOLTAGE_NUM,
.linear_ranges = pca9450_ldo34_volts,
@@ -839,7 +870,7 @@ static struct pca9450_regulator_desc pca9450bc_regulators[] = {
.of_match = of_match_ptr("LDO4"),
.regulators_node = of_match_ptr("regulators"),
.id = PCA9450_LDO4,
- .ops = &pca9450_ldo_regulator_ops,
+ .ops = &pca9450_ldo_suspend_regulator_ops,
.type = REGULATOR_VOLTAGE,
.n_voltages = PCA9450_LDO4_VOLTAGE_NUM,
.linear_ranges = pca9450_ldo34_volts,
@@ -1040,7 +1071,7 @@ static struct pca9450_regulator_desc pca9451a_regulators[] = {
.of_match = of_match_ptr("LDO3"),
.regulators_node = of_match_ptr("regulators"),
.id = PCA9450_LDO3,
- .ops = &pca9450_ldo_regulator_ops,
+ .ops = &pca9450_ldo_suspend_regulator_ops,
.type = REGULATOR_VOLTAGE,
.n_voltages = PCA9450_LDO3_VOLTAGE_NUM,
.linear_ranges = pca9450_ldo34_volts,
@@ -1059,7 +1090,7 @@ static struct pca9450_regulator_desc pca9451a_regulators[] = {
.of_match = of_match_ptr("LDO4"),
.regulators_node = of_match_ptr("regulators"),
.id = PCA9450_LDO4,
- .ops = &pca9450_ldo_regulator_ops,
+ .ops = &pca9450_ldo_suspend_regulator_ops,
.type = REGULATOR_VOLTAGE,
.n_voltages = PCA9450_LDO4_VOLTAGE_NUM,
.linear_ranges = pca9450_ldo34_volts,
diff --git a/include/linux/regulator/pca9450.h b/include/linux/regulator/pca9450.h
index 0df8b3c48082..8925e9c9376b 100644
--- a/include/linux/regulator/pca9450.h
+++ b/include/linux/regulator/pca9450.h
@@ -213,6 +213,9 @@ enum {
#define LDO5H_EN_MASK 0xC0
#define LDO5HOUT_MASK 0x0F
+/* LDO ENMODE value: ON in RUN, OFF while PMIC_STBY_REQ is asserted */
+#define LDO_ENMODE_ONREQ_STBYREQ 0x80
+
/* PCA9450_REG_IRQ bits */
#define IRQ_PWRON 0x80
#define IRQ_WDOGB 0x40
--
2.43.0
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH] regulator: pca9450: Support regulator-off-in-suspend
2026-07-24 20:13 [PATCH] regulator: pca9450: Support regulator-off-in-suspend Fabio Estevam
@ 2026-07-28 18:18 ` Mark Brown
2026-07-28 19:55 ` Fabio Estevam
0 siblings, 1 reply; 3+ messages in thread
From: Mark Brown @ 2026-07-28 18:18 UTC (permalink / raw)
To: Fabio Estevam; +Cc: linux-kernel, imx, Fabio Estevam
[-- Attachment #1: Type: text/plain, Size: 1087 bytes --]
On Fri, Jul 24, 2026 at 05:13:22PM -0300, Fabio Estevam wrote:
> The PCA9450 uses each regulator's ENMODE field to control whether the
> regulator remains enabled when the PMIC transitions from RUN to STANDBY
> mode.
> Implement set_suspend_disable() for the buck regulators and LDO3-LDO5
> by programming ENMODE to 10b. This keeps the regulator enabled in RUN
> mode, turns it off when PMIC_STBY_REQ is asserted, and enables it again
> when the PMIC returns to RUN mode.
> +static int pca9450_buck_set_suspend_disable(struct regulator_dev *rdev)
> +{
> + return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
> + rdev->desc->enable_mask,
> + BUCK_ENMODE_ONREQ_STBYREQ);
> +}
> +
> +static int pca9450_ldo_set_suspend_disable(struct regulator_dev *rdev)
> +{
> + return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
> + rdev->desc->enable_mask,
> + LDO_ENMODE_ONREQ_STBYREQ);
> +}
This is the same register that is used to control runtime enable, I
can't see how the runtime and suspend enable operations avoid corrupting
each other's state?
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^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH] regulator: pca9450: Support regulator-off-in-suspend
2026-07-28 18:18 ` Mark Brown
@ 2026-07-28 19:55 ` Fabio Estevam
0 siblings, 0 replies; 3+ messages in thread
From: Fabio Estevam @ 2026-07-28 19:55 UTC (permalink / raw)
To: Mark Brown; +Cc: linux-kernel, imx, Fabio Estevam
Hi Mark,
On Tue, Jul 28, 2026 at 3:18 PM Mark Brown <broonie@kernel.org> wrote:
> This is the same register that is used to control runtime enable, I
> can't see how the runtime and suspend enable operations avoid corrupting
> each other's state?
Yes, I'll rework, run some tests, and send a v2.
Thanks
^ permalink raw reply [flat|nested] 3+ messages in thread
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2026-07-24 20:13 [PATCH] regulator: pca9450: Support regulator-off-in-suspend Fabio Estevam
2026-07-28 18:18 ` Mark Brown
2026-07-28 19:55 ` Fabio Estevam
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