[PATCH v2 0/3] regulator: sy7636a: define and init all resources needed

[PATCH v2 0/3] regulator: sy7636a: define and init all resources needed

[Andreas Kemnade]

The SY7636A has some pins which can be hardwired or used to have more
more advanced power management available. As several devices containing
this regulator have these pins not hardwired, but instead connected to some
GPIO, enhance the driver to have them defined and initialized.
Also add the ability to power off the chip completely by defining some
input power supply.

Actually implementing better power management is planned to be
implemented as a second step. The regulators in the SY7636A should only
be on for a short time during display refresh, but currently they are
unconditionally forcefully enabled by the hwmon part of this chip.

Signed-off-by: Andreas Kemnade <akemnade@kernel.org>
---
Changes in v2:
- en[-gpios] -> enable[-gpios] in yaml/dts/driver
- fix en vs vcom_en in error handling
- comment delay
- drop applied commit (rebased to regulator/for-linus)
- Link to v1: https://lore.kernel.org/r/20250906-sy7636-rsrc-v1-0-e2886a9763a7@kernel.org

---
Andreas Kemnade (3):
      dt-bindings: mfd: sy7636a: Add missing gpio pins and supply
      regulator: sy7636a: add gpios and input regulator
      ARM: dts: imx: e70k02: add sy7636

 .../devicetree/bindings/mfd/silergy,sy7636a.yaml   | 16 +++++++++++++
 arch/arm/boot/dts/nxp/imx/e70k02.dtsi              | 25 +++++++++++++++++++-
 .../arm/boot/dts/nxp/imx/imx6sl-tolino-vision5.dts | 24 +++++++++++++++++++
 .../arm/boot/dts/nxp/imx/imx6sll-kobo-librah2o.dts | 24 +++++++++++++++++++
 drivers/regulator/sy7636a-regulator.c              | 27 ++++++++++++++++++++++
 5 files changed, 115 insertions(+), 1 deletion(-)
---
base-commit: c05d0b32eebadc8be6e53196e99c64cf2bed1d99
change-id: 20250906-sy7636-rsrc-c20aa6baa2c4

Best regards,
--  
Andreas Kemnade <akemnade@kernel.org>

[PATCH v2 1/3] dt-bindings: mfd: sy7636a: Add missing gpio pins and supply

[Andreas Kemnade]

To be able to fully describe how the SY7636A is connected to the system,
add properties for the EN and VCOM_EN pins. To squeeze out every bit
of unused current, in many devices it is possible to power off the
complete chip. Add an input regulator to allow that.

Signed-off-by: Andreas Kemnade <akemnade@kernel.org>
---
 .../devicetree/bindings/mfd/silergy,sy7636a.yaml         | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml b/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml
index ee0be32ac0204..054b97dd0c5c7 100644
--- a/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml
+++ b/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml
@@ -32,6 +32,22 @@ properties:
       Specifying the power good GPIOs.
     maxItems: 1
 
+  enable-gpios:
+    description:
+      If EN pin is not hardwired, specify it here to have it set up.
+    maxItems: 1
+
+  vcom-en-gpios:
+    description:
+      If VCOM_EN pin is not hardwired, specify it here to have it set up.
+    maxItems: 1
+
+  vin-supply:
+    description:
+      Supply for the chip. Some vendor kernels and devicetrees declare this
+      as a GPIO named "pwrall" which does not exist in the datasheet,
+      disabling it makes the chip disappear on the bus.
+
   regulators:
     type: object
 

-- 
2.39.5

[PATCH v2 2/3] regulator: sy7636a: add gpios and input regulator

[Andreas Kemnade]

Initialize input regulator and gpios to proper values to have things
basically working as well as in the case when these things are
hardwired.

Signed-off-by: Andreas Kemnade <akemnade@kernel.org>
---
 drivers/regulator/sy7636a-regulator.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/regulator/sy7636a-regulator.c b/drivers/regulator/sy7636a-regulator.c
index 27e3d939b7bb9..551647bc10520 100644
--- a/drivers/regulator/sy7636a-regulator.c
+++ b/drivers/regulator/sy7636a-regulator.c
@@ -12,6 +12,7 @@
 #include <linux/mfd/sy7636a.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
 #include <linux/regulator/driver.h>
 #include <linux/regulator/machine.h>
 #include <linux/regmap.h>
@@ -19,6 +20,8 @@
 struct sy7636a_data {
 	struct regmap *regmap;
 	struct gpio_desc *pgood_gpio;
+	struct gpio_desc *en_gpio;
+	struct gpio_desc *vcom_en_gpio;
 };
 
 static int sy7636a_get_vcom_voltage_op(struct regulator_dev *rdev)
@@ -98,6 +101,30 @@ static int sy7636a_regulator_probe(struct platform_device *pdev)
 	data->regmap = regmap;
 	data->pgood_gpio = gdp;
 
+	ret = devm_regulator_get_enable_optional(&pdev->dev, "vin");
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret,
+				     "failed to get vin regulator\n");
+
+	data->en_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
+						GPIOD_OUT_HIGH);
+	if (IS_ERR(data->en_gpio))
+		return dev_err_probe(&pdev->dev,
+				     PTR_ERR(data->en_gpio),
+				     "failed to get en gpio\n");
+
+	/* Let VCOM just follow the default power on sequence */
+	data->vcom_en_gpio = devm_gpiod_get_optional(&pdev->dev,
+						     "vcom-en", GPIOD_OUT_LOW);
+	if (IS_ERR(data->vcom_en_gpio))
+		return dev_err_probe(&pdev->dev,
+				     PTR_ERR(data->vcom_en_gpio),
+				     "failed to get vcom-en gpio\n");
+
+	/* if chip was not enabled, give it time to wake up */
+	if (data->en_gpio)
+		usleep_range(2500, 4000);
+
 	platform_set_drvdata(pdev, data);
 
 	ret = regmap_write(regmap, SY7636A_REG_POWER_ON_DELAY_TIME, 0x0);

-- 
2.39.5

[PATCH v2 3/3] ARM: dts: imx: e70k02: add sy7636

[Andreas Kemnade]

Add the EPD PMIC for the e70k02 based devices as a step towards full EPD
support.

Signed-off-by: Andreas Kemnade <akemnade@kernel.org>
Acked-by: Alistair Francis <alistair@alistair23.me>
---
 arch/arm/boot/dts/nxp/imx/e70k02.dtsi              | 25 +++++++++++++++++++++-
 .../arm/boot/dts/nxp/imx/imx6sl-tolino-vision5.dts | 24 +++++++++++++++++++++
 .../arm/boot/dts/nxp/imx/imx6sll-kobo-librah2o.dts | 24 +++++++++++++++++++++
 3 files changed, 72 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/nxp/imx/e70k02.dtsi b/arch/arm/boot/dts/nxp/imx/e70k02.dtsi
index dcc3c9d488a88..b4f42f71c6c49 100644
--- a/arch/arm/boot/dts/nxp/imx/e70k02.dtsi
+++ b/arch/arm/boot/dts/nxp/imx/e70k02.dtsi
@@ -69,6 +69,14 @@ memory@80000000 {
 		reg = <0x80000000 0x20000000>;
 	};
 
+	epd_pmic_supply: regulator-epd-pmic-in {
+		compatible = "regulator-fixed";
+		regulator-name = "epd_pmic_supply";
+		gpio = <&gpio2 14 GPIO_ACTIVE_HIGH>;
+		startup-delay-us = <20000>;
+		enable-active-high;
+	};
+
 	reg_wifi: regulator-wifi {
 		compatible = "regulator-fixed";
 		regulator-name = "SD3_SPWR";
@@ -133,7 +141,22 @@ touchscreen@24 {
 		vdd-supply = <&ldo5_reg>;
 	};
 
-	/* TODO: SY7636 PMIC for E Ink at 0x62 */
+	sy7636: pmic@62 {
+		compatible = "silergy,sy7636a";
+		reg = <0x62>;
+		enable-gpios = <&gpio2 8 GPIO_ACTIVE_HIGH>;
+		vcom-en-gpios = <&gpio2 3 GPIO_ACTIVE_HIGH>;
+		epd-pwr-good-gpios = <&gpio2 13 GPIO_ACTIVE_HIGH>;
+		vin-supply = <&epd_pmic_supply>;
+
+		#thermal-sensor-cells = <0>;
+
+		regulators {
+			reg_epdpmic: vcom {
+				regulator-name = "vcom";
+			};
+		};
+	};
 
 };
 
diff --git a/arch/arm/boot/dts/nxp/imx/imx6sl-tolino-vision5.dts b/arch/arm/boot/dts/nxp/imx/imx6sl-tolino-vision5.dts
index a2534c422a522..f8709a9524093 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6sl-tolino-vision5.dts
+++ b/arch/arm/boot/dts/nxp/imx/imx6sl-tolino-vision5.dts
@@ -26,6 +26,11 @@ / {
 	compatible = "kobo,tolino-vision5", "fsl,imx6sl";
 };
 
+&epd_pmic_supply {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_epd_pmic_supply>;
+};
+
 &gpio_keys {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_gpio_keys>;
@@ -59,6 +64,12 @@ MX6SL_PAD_FEC_RXD1__GPIO4_IO18          0x10059 /* TP_RST */
 		>;
 	};
 
+	pinctrl_epd_pmic_supply: epd-pmic-supplygrp {
+		fsl,pins = <
+			MX6SL_PAD_EPDC_PWRWAKEUP__GPIO2_IO14    0x40010059
+		>;
+	};
+
 	pinctrl_gpio_keys: gpio-keysgrp {
 		fsl,pins = <
 			MX6SL_PAD_FEC_CRS_DV__GPIO4_IO25	0x17059	/* PWR_SW */
@@ -159,6 +170,14 @@ MX6SL_PAD_KEY_COL2__GPIO3_IO28		0x1b8b1 /* ricoh619 bat_low_int */
 		>;
 	};
 
+	pinctrl_sy7636_gpio: sy7636-gpiogrp {
+		fsl,pins = <
+			MX6SL_PAD_EPDC_VCOM0__GPIO2_IO03        0x40010059 /* VCOM_CTRL */
+			MX6SL_PAD_EPDC_PWRCTRL1__GPIO2_IO08     0x40010059 /* EN */
+			MX6SL_PAD_EPDC_PWRSTAT__GPIO2_IO13      0x17059 /* PWR_GOOD */
+		>;
+	};
+
 	pinctrl_uart1: uart1grp {
 		fsl,pins = <
 			MX6SL_PAD_UART1_TXD__UART1_TX_DATA 0x1b0b1
@@ -329,6 +348,11 @@ &ricoh619 {
 	pinctrl-0 = <&pinctrl_ricoh_gpio>;
 };
 
+&sy7636 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_sy7636_gpio>;
+};
+
 &uart1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_uart1>;
diff --git a/arch/arm/boot/dts/nxp/imx/imx6sll-kobo-librah2o.dts b/arch/arm/boot/dts/nxp/imx/imx6sll-kobo-librah2o.dts
index 660620d226f71..19bbe60331b36 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6sll-kobo-librah2o.dts
+++ b/arch/arm/boot/dts/nxp/imx/imx6sll-kobo-librah2o.dts
@@ -36,6 +36,11 @@ &cpu0 {
 	soc-supply = <&dcdc1_reg>;
 };
 
+&epd_pmic_supply {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_epd_pmic_supply>;
+};
+
 &gpio_keys {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_gpio_keys>;
@@ -69,6 +74,12 @@ MX6SLL_PAD_GPIO4_IO18__GPIO4_IO18	0x10059 /* TP_RST */
 		>;
 	};
 
+	pinctrl_epd_pmic_supply: epd-pmic-supplygrp {
+		fsl,pins = <
+			MX6SLL_PAD_EPDC_PWR_WAKE__GPIO2_IO14    0x40010059
+		>;
+	};
+
 	pinctrl_gpio_keys: gpio-keysgrp {
 		fsl,pins = <
 			MX6SLL_PAD_GPIO4_IO25__GPIO4_IO25	0x17059	/* PWR_SW */
@@ -169,6 +180,14 @@ MX6SLL_PAD_KEY_COL2__GPIO3_IO28		0x1b8b1 /* ricoh619 bat_low_int */
 		>;
 	};
 
+	pinctrl_sy7636_gpio: sy7636-gpiogrp {
+		fsl,pins = <
+			MX6SLL_PAD_EPDC_VCOM0__GPIO2_IO03       0x40010059 /* VCOM_CTRL */
+			MX6SLL_PAD_EPDC_PWR_CTRL1__GPIO2_IO08   0x40010059 /* EN */
+			MX6SLL_PAD_EPDC_PWR_STAT__GPIO2_IO13    0x17059 /* PWR_GOOD */
+		>;
+	};
+
 	pinctrl_uart1: uart1grp {
 		fsl,pins = <
 			MX6SLL_PAD_UART1_TXD__UART1_DCE_TX 0x1b0b1
@@ -319,6 +338,11 @@ &ricoh619 {
 	pinctrl-0 = <&pinctrl_ricoh_gpio>;
 };
 
+&sy7636 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_sy7636_gpio>;
+};
+
 &uart1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_uart1>;

-- 
2.39.5

Re: [PATCH v2 1/3] dt-bindings: mfd: sy7636a: Add missing gpio pins and supply

[Krzysztof Kozlowski]

On Tue, Sep 09, 2025 at 10:33:02PM +0200, Andreas Kemnade wrote:
> To be able to fully describe how the SY7636A is connected to the system,
> add properties for the EN and VCOM_EN pins. To squeeze out every bit
> of unused current, in many devices it is possible to power off the
> complete chip. Add an input regulator to allow that.
> 
> Signed-off-by: Andreas Kemnade <akemnade@kernel.org>
> ---
>  .../devicetree/bindings/mfd/silergy,sy7636a.yaml         | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

Re: [PATCH v2 1/3] dt-bindings: mfd: sy7636a: Add missing gpio pins and supply

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 450 bytes --]

On Tue, Sep 09, 2025 at 10:33:02PM +0200, Andreas Kemnade wrote:
> To be able to fully describe how the SY7636A is connected to the system,
> add properties for the EN and VCOM_EN pins. To squeeze out every bit
> of unused current, in many devices it is possible to power off the
> complete chip. Add an input regulator to allow that.

Lee, the code for this is in the regulator tree so it probably makes
sense to merge the binding update there too?

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Re: [PATCH v2 2/3] regulator: sy7636a: add gpios and input regulator

[Peng Fan]

On Tue, Sep 09, 2025 at 10:33:03PM +0200, Andreas Kemnade wrote:
>Initialize input regulator and gpios to proper values to have things
>basically working as well as in the case when these things are
>hardwired.
>
>Signed-off-by: Andreas Kemnade <akemnade@kernel.org>

Reviewed-by: Peng Fan <peng.fan@nxp.com>

Re: [PATCH v2 3/3] ARM: dts: imx: e70k02: add sy7636

[Peng Fan]

On Tue, Sep 09, 2025 at 10:33:04PM +0200, Andreas Kemnade wrote:
>Add the EPD PMIC for the e70k02 based devices as a step towards full EPD
>support.
>
>Signed-off-by: Andreas Kemnade <akemnade@kernel.org>
>Acked-by: Alistair Francis <alistair@alistair23.me>

Reviewed-by: Peng Fan <peng.fan@nxp.com>

Re: [PATCH v2 1/3] dt-bindings: mfd: sy7636a: Add missing gpio pins and supply

[Frank Li]

On Tue, Sep 09, 2025 at 10:33:02PM +0200, Andreas Kemnade wrote:
> To be able to fully describe how the SY7636A is connected to the system,
> add properties for the EN and VCOM_EN pins. To squeeze out every bit
> of unused current, in many devices it is possible to power off the
> complete chip. Add an input regulator to allow that.
>
> Signed-off-by: Andreas Kemnade <akemnade@kernel.org>
> ---
>  .../devicetree/bindings/mfd/silergy,sy7636a.yaml         | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml b/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml
> index ee0be32ac0204..054b97dd0c5c7 100644
> --- a/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml
> +++ b/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml
> @@ -32,6 +32,22 @@ properties:
>        Specifying the power good GPIOs.
>      maxItems: 1
>
> +  enable-gpios:
> +    description:
> +      If EN pin is not hardwired, specify it here to have it set up.

Need descript function of enabel-gpios, you can ref data sheet sy7636a.

"enable-gpios" is good self documented by property name, needn't
description at all.

> +    maxItems: 1
> +
> +  vcom-en-gpios:
> +    description:
> +      If VCOM_EN pin is not hardwired, specify it here to have it set up.
> +    maxItems: 1
> +
> +  vin-supply:
> +    description:
> +      Supply for the chip. Some vendor kernels and devicetrees declare this
> +      as a GPIO named "pwrall" which does not exist in the datasheet,
> +      disabling it makes the chip disappear on the bus.
> +

The same here, descript function. such as power supply for whole chip.

Frank

>    regulators:
>      type: object
>
>
> --
> 2.39.5
>

Re: [PATCH v2 1/3] dt-bindings: mfd: sy7636a: Add missing gpio pins and supply

[Andreas Kemnade]

Am Wed, 10 Sep 2025 11:45:35 -0400
schrieb Frank Li <Frank.li@nxp.com>:

> On Tue, Sep 09, 2025 at 10:33:02PM +0200, Andreas Kemnade wrote:
> > To be able to fully describe how the SY7636A is connected to the system,
> > add properties for the EN and VCOM_EN pins. To squeeze out every bit
> > of unused current, in many devices it is possible to power off the
> > complete chip. Add an input regulator to allow that.
> >
> > Signed-off-by: Andreas Kemnade <akemnade@kernel.org>
> > ---
> >  .../devicetree/bindings/mfd/silergy,sy7636a.yaml         | 16 ++++++++++++++++
> >  1 file changed, 16 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml b/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml
> > index ee0be32ac0204..054b97dd0c5c7 100644
> > --- a/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml
> > +++ b/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml
> > @@ -32,6 +32,22 @@ properties:
> >        Specifying the power good GPIOs.
> >      maxItems: 1
> >
> > +  enable-gpios:
> > +    description:
> > +      If EN pin is not hardwired, specify it here to have it set up.  
> 
> Need descript function of enabel-gpios, you can ref data sheet sy7636a.
> 
> "enable-gpios" is good self documented by property name, needn't
> description at all.
> 
What you are saying is contradictory. I would prefer to have a mapping
crystal clear visible between properties and pins. That is why I want
that description. I remember I have got the datasheet from the company
site with registration without acknowledging any terms. But I do not
find that site.

> > +    maxItems: 1
> > +
> > +  vcom-en-gpios:
> > +    description:
> > +      If VCOM_EN pin is not hardwired, specify it here to have it set up.
> > +    maxItems: 1
> > +
> > +  vin-supply:
> > +    description:
> > +      Supply for the chip. Some vendor kernels and devicetrees declare this
> > +      as a GPIO named "pwrall" which does not exist in the datasheet,
> > +      disabling it makes the chip disappear on the bus.
> > +  
> 
> The same here, descript function. such as power supply for whole chip.

I think it is useful what I am writing here. DT maintainers are
apparently fine with it, since it has earned a Reviewed-By.

Regards,
Andreas