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Message-ID: <7a2dfaab-5340-236a-064d-15db3e00f409@pengutronix.de>
Date:   Tue, 20 Dec 2022 17:50:59 +0100
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Subject: Re: [PATCH v2 1/3] ARM: dts: imx7d-remarkable2: Enable the cyttsp5
Content-Language: en-US
To:     Marco Felsch <m.felsch@pengutronix.de>,
        Alistair Francis <alistair@alistair23.me>
Cc:     devicetree@vger.kernel.org, kernel@pengutronix.de, arnd@arndb.de,
        festevam@gmail.com, s.hauer@pengutronix.de,
        linux-kernel@vger.kernel.org, jernej.skrabec@gmail.com,
        linux@armlinux.org.uk, robh+dt@kernel.org, linux-imx@nxp.com,
        krzysztof.kozlowski+dt@linaro.org, alistair23@gmail.com,
        shawnguo@kernel.org, linux-arm-kernel@lists.infradead.org
References: <20221220112927.440506-1-alistair@alistair23.me>
 <20221220112927.440506-2-alistair@alistair23.me>
 <20221220132033.s5idqrol5kqxjasy@pengutronix.de>
From:   Ahmad Fatoum <a.fatoum@pengutronix.de>
In-Reply-To: <20221220132033.s5idqrol5kqxjasy@pengutronix.de>
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Precedence: bulk

Hello Alistair,
Hello Marco,

On 20.12.22 14:20, Marco Felsch wrote:
> Hi Alistair,                                                                                                                            
> 
> thanks for your patch, please see below.
> 
> On 22-12-20, Alistair Francis wrote:
>> Add support for the cyttsp5 touchscreen controller for the reMarkable 2.
>>
>> Signed-off-by: Alistair Francis <alistair@alistair23.me>
>> ---
>>  arch/arm/boot/dts/imx7d-remarkable2.dts | 98 +++++++++++++++++++++++++
>>  1 file changed, 98 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/imx7d-remarkable2.dts b/arch/arm/boot/dts/imx7d-remarkable2.dts
>> index 8b2f11e85e05..a138b292ec6a 100644
>> --- a/arch/arm/boot/dts/imx7d-remarkable2.dts
>> +++ b/arch/arm/boot/dts/imx7d-remarkable2.dts
>> @@ -8,6 +8,7 @@
>>  /dts-v1/;
>>  
>>  #include "imx7d.dtsi"
>> +#include <dt-bindings/input/linux-event-codes.h>
>>  
>>  / {
>>  	model = "reMarkable 2.0";
>> @@ -69,6 +70,18 @@ reg_digitizer: regulator-digitizer {
>>  		startup-delay-us = <100000>; /* 100 ms */
>>  	};
>>  
>> +	reg_touch: regulator-touch {
>> +		compatible = "regulator-fixed";
>> +		regulator-name = "VDD_3V3_TOUCH";
>> +		regulator-min-microvolt = <3300000>;
>> +		regulator-max-microvolt = <3300000>;
>> +		pinctrl-names = "default", "sleep";
>> +		pinctrl-0 = <&pinctrl_touch_reg>;
>> +		pinctrl-1 = <&pinctrl_touch_reg>;
> 
> Why do we need a "sleep" state here?
> 
>> +		gpio = <&gpio1 11 GPIO_ACTIVE_HIGH>;
>> +		enable-active-high;
>> +	};
>> +
>>  	wifi_pwrseq: wifi_pwrseq {
>>  		compatible = "mmc-pwrseq-simple";
>>  		pinctrl-names = "default";
>> @@ -106,6 +119,68 @@ wacom_digitizer: digitizer@9 {
>>  	};
>>  };
>>  
>> +&i2c3 {
>> +	clock-frequency = <100000>;
> 
> This can be set to 400kHz, the driver handle the quirks internal.

I would either leave this at 100kHz or increase to the maximum of
384 kHz. DT is supposed to describe the hardware and if 400 kHz
isn't a safe frequency, it should be avoided, even if the Linux
driver handles it gracefully.

Cheers,
Ahmad

> 
> Regards,
>   Marco
> 
>> +	pinctrl-names = "default";
>> +	pinctrl-0 = <&pinctrl_i2c3>;
>> +	status = "okay";
>> +
>> +	touchscreen@24 {
>> +		compatible = "cypress,tt21000";
>> +		reg = <0x24>;
>> +		pinctrl-names = "default";
>> +		pinctrl-0 = <&pinctrl_touch>;
>> +		interrupt-parent = <&gpio1>;
>> +		interrupts = <14 IRQ_TYPE_EDGE_FALLING>;
>> +		reset-gpios = <&gpio1 13 GPIO_ACTIVE_LOW>;
>> +		vdd-supply = <&reg_touch>;
>> +		touchscreen-size-x = <880>;
>> +		touchscreen-size-y = <1280>;
>> +		#address-cells = <1>;
>> +		#size-cells = <0>;
>> +
>> +		button@0 {
>> +			reg = <0>;
>> +			linux,keycodes = <KEY_HOMEPAGE>;
>> +		};
>> +
>> +		button@1 {
>> +			reg = <1>;
>> +			linux,keycodes = <KEY_MENU>;
>> +		};
>> +
>> +		button@2 {
>> +			reg = <2>;
>> +			linux,keycodes = <KEY_BACK>;
>> +		};
>> +
>> +		button@3 {
>> +			reg = <3>;
>> +			linux,keycodes = <KEY_SEARCH>;
>> +		};
>> +
>> +		button@4 {
>> +			reg = <4>;
>> +			linux,keycodes = <KEY_VOLUMEDOWN>;
>> +		};
>> +
>> +		button@5 {
>> +			reg = <5>;
>> +			linux,keycodes = <KEY_VOLUMEUP>;
>> +		};
>> +
>> +		button@6 {
>> +			reg = <6>;
>> +			linux,keycodes = <KEY_CAMERA>;
>> +		};
>> +
>> +		button@7 {
>> +			reg = <7>;
>> +			linux,keycodes = <KEY_POWER>;
>> +		};
>> +	};
>> +};
>> +
>>  &i2c4 {
>>  	clock-frequency = <100000>;
>>  	pinctrl-names = "default", "sleep";
>> @@ -232,6 +307,15 @@ MX7D_PAD_ENET1_RGMII_TXC__GPIO7_IO11	0x00000014
>>  		>;
>>  	};
>>  
>> +	pinctrl_touch: touchgrp {
>> +		fsl,pins = <
>> +			/* CYTTSP interrupt */
>> +			MX7D_PAD_GPIO1_IO14__GPIO1_IO14		0x54
>> +			/* CYTTSP reset */
>> +			MX7D_PAD_GPIO1_IO13__GPIO1_IO13		0x04
>> +		>;
>> +	};
>> +
>>  	pinctrl_i2c1: i2c1grp {
>>  		fsl,pins = <
>>  			MX7D_PAD_I2C1_SDA__I2C1_SDA		0x4000007f
>> @@ -239,6 +323,13 @@ MX7D_PAD_I2C1_SCL__I2C1_SCL		0x4000007f
>>  		>;
>>  	};
>>  
>> +	pinctrl_i2c3: i2c3grp {
>> +		fsl,pins = <
>> +			MX7D_PAD_I2C3_SDA__I2C3_SDA		0x4000007f
>> +			MX7D_PAD_I2C3_SCL__I2C3_SCL		0x4000007f
>> +		>;
>> +	};
>> +
>>  	pinctrl_i2c4: i2c4grp {
>>  		fsl,pins = <
>>  			MX7D_PAD_I2C4_SDA__I2C4_SDA		0x4000007f
>> @@ -246,6 +337,13 @@ MX7D_PAD_I2C4_SCL__I2C4_SCL		0x4000007f
>>  		>;
>>  	};
>>  
>> +	pinctrl_touch_reg: touchreggrp {
>> +		fsl,pins = <
>> +			/* TOUCH_PWR_EN */
>> +			MX7D_PAD_GPIO1_IO11__GPIO1_IO11		0x14
>> +		>;
>> +	};
>> +
>>  	pinctrl_uart1: uart1grp {
>>  		fsl,pins = <
>>  			MX7D_PAD_UART1_TX_DATA__UART1_DCE_TX	0x79
>> -- 
>> 2.38.1
>>
>>
>>
> 
> 

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