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[PATCH v2 4/4] ARM: dts: amlogic: meson8-fernsehfee3: Describe regulators

J. Neuschäfer via B4 Relay posted 4 patches 9 months, 2 weeks ago
[PATCH v2 4/4] ARM: dts: amlogic: meson8-fernsehfee3: Describe regulators
Posted by J. Neuschäfer via B4 Relay 9 months, 2 weeks ago 
From: "J. Neuschäfer" <j.ne@posteo.net>

The fernsehfee3 board uses a Ricoh RN5T618 PMIC to generate various
voltages. Board schematics are not available, but the regulator voltages
found in /sys/kernel/debug/regulator/regulator_summary match those in
meson8m2-mxiii-plus.dts:

 DCDC1               0    0      0 unknown  1100mV     0mA     0mV     0mV
 DCDC2               0    0      0 unknown  1150mV     0mA     0mV     0mV
 DCDC3               0    0      0 unknown  1500mV     0mA     0mV     0mV
 LDO1                0    0      0 unknown  2900mV     0mA     0mV     0mV
 LDO2                0    0      0 unknown  1800mV     0mA     0mV     0mV
 LDO3                0    0      0 unknown  1800mV     0mA     0mV     0mV
 LDO4                0    0      0 unknown  2850mV     0mA     0mV     0mV
 LDO5                0    0      0 unknown  1800mV     0mA     0mV     0mV
 LDORTC1             0    0      0 unknown  2700mV     0mA     0mV     0mV
 LDORTC2             0    0      0 unknown   900mV     0mA     0mV     0mV

This patch takes the following approach:

 - Copy RN5T618 regulator nodes from meson8m2-mxiii-plus.dts
 - Remove some of the regulator names, which do not seem to apply
 - Verify regulator supply relations by starting without any relations
   (and without regulator-always-on) and seeing what breaks when the
   kernel turns off "unused" regulators.

This results in the following observations:

 - When LDO1 is turned off, the board resets
 - When DCDC1, DCDC2, DCDC3, LDO2, or LDO5 are turned off, the board (as
   observed through the serial port) stops running, so these must stay on
   at all times.
 - LDO4 (VCC2V8) appears to be unused on this board.
 - LDO3 (VCC1V8_USB) must stay on in order for USB to work, both the
   external USB ports and the internal USB wifi module.

The cpu-supply and mali-supply relations are also copied from
meson8m2-mxiii-plus.dts

Signed-off-by: J. Neuschäfer <j.ne@posteo.net>
---

Checklist used during the development of this patch (when a given
regulator is not forced to stay on, which features work/fail?):

 regulator | boot | run  | USB  | WLAN | eMMC | SD   | Eth
 ----------|------|------|------|------|------|------|------
  baseline | ok   | ok   | ok   | ok   | ok   | ok   | ok
  empty¹   | ok   | ok   | ok   | ok   | ok   | init²| ok
  DCDC1    | ok   | STOP |      |      |      |      |
  DCDC2    | ok   | STOP |      |      |      |      |
  DCDC3    | ok   | STOP |      |      |      |      |
  LDO1     | ok   | RESET| FAIL | FAIL | ok   | init | ok
  LDO2     | ok   | STOP | ok   | ok   | ok   | ok   |
  LDO3     | ok   | ok   | FAIL | FAIL | ok   | ok   | ok
  LDO4     | ok   | ok   | ok   | ok   | ok   | ok   | ok
  LDO5     | ok   | STOP |      |      |      |      |
  LDORTC1  |      |      |      |      |      |      |
  LDORTC2  |      |      |      |      |      |      |

¹: empty list of regulators
²: fails to initialize when plugged in at boot, only inits on hotplug


V2:
- new patch
---
 arch/arm/boot/dts/amlogic/meson8-fernsehfee3.dts | 91 ++++++++++++++++++++++++
 1 file changed, 91 insertions(+)

diff --git a/arch/arm/boot/dts/amlogic/meson8-fernsehfee3.dts b/arch/arm/boot/dts/amlogic/meson8-fernsehfee3.dts
index 3f9e2e5d8d5bd7ca7eb31e9b6cc7a591666c89ea..4e52447d51bd2d1d04e4ce21ddf598bc80a4c5f4 100644
--- a/arch/arm/boot/dts/amlogic/meson8-fernsehfee3.dts
+++ b/arch/arm/boot/dts/amlogic/meson8-fernsehfee3.dts
@@ -85,6 +85,10 @@ wifi_3v3: regulator-wifi {
 	};
 };
 
+&cpu0 {
+	cpu-supply = <&vcck>;
+};
+
 &ethmac {
 	status = "okay";
 	pinctrl-0 = <&eth_pins>;
@@ -117,6 +121,87 @@ pmic@32 {
 		compatible = "ricoh,rn5t618";
 		reg = <0x32>;
 		system-power-controller;
+
+		regulators {
+			vcck: DCDC1 {
+				regulator-name = "VCCK";
+				regulator-min-microvolt = <825000>;
+				regulator-max-microvolt = <1150000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			vddee: DCDC2 {
+				/* the output is also used as VDDAO */
+				regulator-name = "VDD_EE";
+				regulator-min-microvolt = <950000>;
+				regulator-max-microvolt = <1150000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			DCDC3 {
+				regulator-name = "VDD_DDR";
+				regulator-min-microvolt = <1500000>;
+				regulator-max-microvolt = <1500000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			LDO1 {
+				regulator-name = "VDDIO_AO28";
+				regulator-min-microvolt = <2900000>;
+				regulator-max-microvolt = <2900000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			LDO2 {
+				regulator-name = "VDDIO_AO18";
+				regulator-min-microvolt = <1800000>;
+				regulator-max-microvolt = <1800000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			vcc1v8_usb: LDO3 {
+				regulator-name = "VCC1V8_USB";
+				regulator-min-microvolt = <1800000>;
+				regulator-max-microvolt = <1800000>;
+				regulator-boot-on;
+			};
+
+			LDO4 {
+				/* This one appears to be unused */
+				regulator-name = "VCC2V8";
+				regulator-min-microvolt = <2850000>;
+				regulator-max-microvolt = <2850000>;
+			};
+
+			LDO5 {
+				regulator-name = "AVDD1V8";
+				regulator-min-microvolt = <1800000>;
+				regulator-max-microvolt = <1800000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			LDORTC1 {
+				regulator-name = "VDD_LDO";
+				regulator-min-microvolt = <2700000>;
+				regulator-max-microvolt = <2700000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			LDORTC2 {
+				regulator-name = "RTC_0V9";
+				regulator-min-microvolt = <900000>;
+				regulator-max-microvolt = <900000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+		};
 	};
 
 	eeprom@50 {
@@ -137,6 +222,10 @@ &i2c_B {
 	/* TODO: SiI9293 HDMI receiver @ 0x39 */
 };
 
+&mali {
+	mali-supply = <&vddee>;
+};
+
 &sdhc {
 	status = "okay";
 	pinctrl-0 = <&sdxc_c_pins>;
@@ -188,6 +277,7 @@ &usb0 {
 
 &usb0_phy {
 	status = "okay";
+	phy-supply = <&vcc1v8_usb>;
 };
 
 &usb1 {
@@ -206,6 +296,7 @@ wifi: wifi@1 {
 
 &usb1_phy {
 	status = "okay";
+	phy-supply = <&vcc1v8_usb>;
 };
 
 &ir_receiver {

-- 
2.48.0.rc1.219.gb6b6757d772
Re: [PATCH v2 4/4] ARM: dts: amlogic: meson8-fernsehfee3: Describe regulators
Posted by Martin Blumenstingl 9 months, 1 week ago 
On Mon, Apr 28, 2025 at 12:44 PM J. Neuschäfer via B4 Relay
<devnull+j.ne.posteo.net@kernel.org> wrote:
>
> From: "J. Neuschäfer" <j.ne@posteo.net>
>
> The fernsehfee3 board uses a Ricoh RN5T618 PMIC to generate various
> voltages. Board schematics are not available, but the regulator voltages
> found in /sys/kernel/debug/regulator/regulator_summary match those in
> meson8m2-mxiii-plus.dts:
>
>  DCDC1               0    0      0 unknown  1100mV     0mA     0mV     0mV
>  DCDC2               0    0      0 unknown  1150mV     0mA     0mV     0mV
>  DCDC3               0    0      0 unknown  1500mV     0mA     0mV     0mV
>  LDO1                0    0      0 unknown  2900mV     0mA     0mV     0mV
>  LDO2                0    0      0 unknown  1800mV     0mA     0mV     0mV
>  LDO3                0    0      0 unknown  1800mV     0mA     0mV     0mV
>  LDO4                0    0      0 unknown  2850mV     0mA     0mV     0mV
>  LDO5                0    0      0 unknown  1800mV     0mA     0mV     0mV
>  LDORTC1             0    0      0 unknown  2700mV     0mA     0mV     0mV
>  LDORTC2             0    0      0 unknown   900mV     0mA     0mV     0mV
>
> This patch takes the following approach:
>
>  - Copy RN5T618 regulator nodes from meson8m2-mxiii-plus.dts
>  - Remove some of the regulator names, which do not seem to apply
>  - Verify regulator supply relations by starting without any relations
>    (and without regulator-always-on) and seeing what breaks when the
>    kernel turns off "unused" regulators.
>
> This results in the following observations:
>
>  - When LDO1 is turned off, the board resets
>  - When DCDC1, DCDC2, DCDC3, LDO2, or LDO5 are turned off, the board (as
>    observed through the serial port) stops running, so these must stay on
>    at all times.
>  - LDO4 (VCC2V8) appears to be unused on this board.
>  - LDO3 (VCC1V8_USB) must stay on in order for USB to work, both the
>    external USB ports and the internal USB wifi module.
>
> The cpu-supply and mali-supply relations are also copied from
> meson8m2-mxiii-plus.dts
>
> Signed-off-by: J. Neuschäfer <j.ne@posteo.net>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>

Thanks for the detailed summary!

Patchew 2.1-devel-b67e4c2

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