Re: [PATCH v2 2/8] arm64: dts: mediatek: cherry: Wire up the ChromeOS EC and GSC

Chen-Yu Tsai
2022-07-25T10:04:44Z

On Thu, Jul 21, 2022 at 10:51 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com> wrote:
>
> Wire up the ChromeOS Embedded Controller on SPI0 and its communication
> channel via SCP RPMSG along with all of the offered functionality,
> including Keyboard, Smart Battery Metrics (SBS), PWM controller, I2C
> tunnel, regulators and Type-C connector management.
>
> While at it, also add support for the Cr50 Google Security Chip (GSC)
> found on this platform on I2C3 to support TPM and also use it as an
> entropy source for the kernel.
>
> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> ---
> .../boot/dts/mediatek/mt8195-cherry.dtsi | 93 +++++++++++++++++++
> 1 file changed, 93 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi b/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
> index feebbe367e93..87ac2b4f9814 100644
> --- a/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
> +++ b/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
> @@ -149,6 +149,14 @@ &i2c3 {
> clock-frequency = <400000>;
> pinctrl-names = "default";
> pinctrl-0 = <&i2c3_pins>;
> +
> + cr50@50 {

tpm?

Also I think the CR50 should be a separate patch. It is not related
to the EC.

> + compatible = "google,cr50";
> + reg = <0x50>;
> + interrupts-extended = <&pio 88 IRQ_TYPE_EDGE_FALLING>;
> + pinctrl-names = "default";
> + pinctrl-0 = <&cr50_int>;
> + };
> };
>
> &i2c4 {
> @@ -426,6 +434,21 @@ &pio {
> "AP_SPI_FLASH_MOSI",
> "AP_SPI_FLASH_MISO";
>
> + cr50_int: cr50-irq-default-pins {
> + pins-gsc-ap-int-odl {
> + pinmux = <PINMUX_GPIO88__FUNC_GPIO88>;
> + input-enable;
> + };
> + };
> +
> + cros_ec_int: cros-ec-irq-default-pins {
> + pins-ec-ap-int-odl {
> + pinmux = <PINMUX_GPIO4__FUNC_GPIO4>;
> + bias-pull-up = <MTK_PUPD_SET_R1R0_01>;
> + input-enable;
> + };
> + };
> +
> i2c0_pins: i2c0-default-pins {
> pins-bus {
> pinmux = <PINMUX_GPIO8__FUNC_SDA0>,
> @@ -669,6 +692,11 @@ &scp {
> memory-region = <&scp_mem>;
> pinctrl-names = "default";
> pinctrl-0 = <&scp_pins>;
> +
> + cros-ec-rpmsg {
> + compatible = "google,cros-ec-rpmsg";
> + mediatek,rpmsg-name = "cros-ec-rpmsg";
> + };
> };
>
> &spi0 {
> @@ -677,6 +705,68 @@ &spi0 {
> pinctrl-names = "default";
> pinctrl-0 = <&spi0_pins>;
> mediatek,pad-select = <0>;
> +
> + cros_ec: ec@0 {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + compatible = "google,cros-ec-spi";
> + reg = <0>;
> + interrupts-extended = <&pio 4 IRQ_TYPE_LEVEL_LOW>;
> + pinctrl-names = "default";
> + pinctrl-0 = <&cros_ec_int>;
> + spi-max-frequency = <3000000>;
> +
> + cros_ec_pwm: ec-pwm {
> + compatible = "google,cros-ec-pwm";
> + #pwm-cells = <1>;
> + };

This only serves the keyboard backlight LED. However, we have a better
interface for that, described in

Documentation/devicetree/bindings/chrome/google,cros-kbd-led-backlight.yaml

I think we should go with that one.

ChenYu

> +
> + i2c_tunnel: i2c-tunnel {
> + compatible = "google,cros-ec-i2c-tunnel";
> + google,remote-bus = <0>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + };
> +
> + mt_pmic_vmc_ldo_reg: regulator@0 {
> + compatible = "google,cros-ec-regulator";
> + reg = <0>;
> + regulator-name = "mt_pmic_vmc_ldo";
> + regulator-min-microvolt = <1200000>;
> + regulator-max-microvolt = <3600000>;
> + };
> +
> + mt_pmic_vmch_ldo_reg: regulator@1 {
> + compatible = "google,cros-ec-regulator";
> + reg = <1>;
> + regulator-name = "mt_pmic_vmch_ldo";
> + regulator-min-microvolt = <2700000>;
> + regulator-max-microvolt = <3600000>;
> + };
> +
> + typec {
> + compatible = "google,cros-ec-typec";
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + usb_c0: connector@0 {
> + compatible = "usb-c-connector";
> + reg = <0>;
> + power-role = "dual";
> + data-role = "host";
> + try-power-role = "source";
> + };
> +
> + usb_c1: connector@1 {
> + compatible = "usb-c-connector";
> + reg = <1>;
> + power-role = "dual";
> + data-role = "host";
> + try-power-role = "source";
> + };
> + };
> + };
> };
>
> &u3phy0 {
> @@ -728,3 +818,6 @@ &xhci3 {
> vusb33-supply = <&mt6359_vusb_ldo_reg>;
> vbus-supply = <&usb_vbus>;
> };
> +
> +#include <arm/cros-ec-keyboard.dtsi>
> +#include <arm/cros-ec-sbs.dtsi>
> --
> 2.35.1
>
>