Re: [PATCH v2 4/4] arm64: dts: exynosautov9: add usi device tree nodes

From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
To: Chanho Park <chanho61.park@samsung.com>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Rob Herring <robh+dt@kernel.org>
Cc: Alim Akhtar <alim.akhtar@samsung.com>,
	Sam Protsenko <semen.protsenko@linaro.org>,
	Jaewon Kim <jaewon02.kim@samsung.com>,
	devicetree@vger.kernel.org, linux-samsung-soc@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v2 4/4] arm64: dts: exynosautov9: add usi device tree nodes
Date: Thu, 30 Jun 2022 09:14:14 +0200	[thread overview]
Message-ID: <7e6ec956-b679-de68-1a4f-61105e3898cf@linaro.org> (raw)
In-Reply-To: <0588d46af06f9d932f4a526c3b04601079b4fde1.1656554759.git.chanho61.park@samsung.com>

On 30/06/2022 04:16, Chanho Park wrote:
> Universal Serial Interface (USI) supports three types of serial interface
> such as Universal Asynchronous Receiver and Transmitter (UART), Serial
> Peripheral Interface (SPI), and Inter-Integrated Circuit (I2C).
> Each protocols can be working independently and configured as one of
> those using external configuration inputs.
> Exynos Auto v9 SoC support 12 USIs. When a USI uses two pins such as i2c
> and 3 wire uarts(RX/TX only), we can use remain two pins as i2c mode.
> So, we can define one USI node that includes serial/spi and hsi2c.
> usi_i2c nodes can be used only for i2c mode.
> 
> We can have below combinations for one USI.
> 1) The usi node is used either 4 pin uart or 4 pin spi
>  -> No usi_i2c can be used
> 2) The usi node is used 2 pin uart(RX/TX) and i2c(SDA/SCL)
>  -> usi_i2c should be enabled to use the latter i2c
> 3) The usi node is used i2c(SDA/SCL) and i2c(SDA/SCL)
>  -> usi_i2c should be enabled to use the latter i2c
> 
> By default, all USIs are initially set to uart mode by below setting.
> samsung,mode = <USI_V2_UART>;
> You can change it either USI_V2_SPI or USI_V2_I2C.
> 
> Signed-off-by: Chanho Park <chanho61.park@samsung.com>
> ---
>  .../boot/dts/exynos/exynosautov9-sadk.dts     |    2 +
>  arch/arm64/boot/dts/exynos/exynosautov9.dtsi  | 1077 ++++++++++++++++-
>  2 files changed, 1074 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/exynos/exynosautov9-sadk.dts b/arch/arm64/boot/dts/exynos/exynosautov9-sadk.dts
> index 2b30a7458297..eec3192c0631 100644
> --- a/arch/arm64/boot/dts/exynos/exynosautov9-sadk.dts
> +++ b/arch/arm64/boot/dts/exynos/exynosautov9-sadk.dts
> @@ -50,6 +50,7 @@ ufs_1_fixed_vcc_reg: regulator-1 {
>  };
>  
>  &serial_0 {
> +	pinctrl-0 = <&uart0_bus_dual>;
>  	status = "okay";
>  };
>  
> @@ -74,6 +75,7 @@ &ufs_1 {
>  };
>  
>  &usi_0 {
> +	samsung,clkreq-on; /* needed for UART mode */
>  	status = "okay";
>  };
>  
> diff --git a/arch/arm64/boot/dts/exynos/exynosautov9.dtsi b/arch/arm64/boot/dts/exynos/exynosautov9.dtsi
> index c4cfa93e4c2e..2013718532f3 100644
> --- a/arch/arm64/boot/dts/exynos/exynosautov9.dtsi
> +++ b/arch/arm64/boot/dts/exynos/exynosautov9.dtsi
> @@ -351,12 +351,17 @@ syscon_peric0: syscon@10220000 {
>  			reg = <0x10220000 0x2000>;
>  		};
>  
> +		syscon_peric1: syscon@10820000 {
> +			compatible = "samsung,exynosautov9-sysreg", "syscon";
> +			reg = <0x10820000 0x2000>;
> +		};
> +
>  		usi_0: usi@103000c0 {
> -			compatible = "samsung,exynos850-usi";
> +			compatible = "samsung,exynosautov9-usi",
> +				     "samsung,exynos850-usi";

This change should be separate.

>  			reg = <0x103000c0 0x20>;
>  			samsung,sysreg = <&syscon_peric0 0x1000>;
>  			samsung,mode = <USI_V2_UART>;
> -			samsung,clkreq-on; /* needed for UART mode */
>  			#address-cells = <1>;
>  			#size-cells = <1>;
>  			ranges;
> @@ -365,16 +370,1078 @@ usi_0: usi@103000c0 {
>  			clock-names = "pclk", "ipclk";
>  			status = "disabled";
>  
> -			/* USI: UART */
>  			serial_0: serial@10300000 {
> -				compatible = "samsung,exynos850-uart";
> +				compatible = "samsung,exynosautov9-uart",
> +					     "samsung,exynos850-uart";
>  				reg = <0x10300000 0xc0>;

As well.

Best regards,
Krzysztof