Received-SPF: pass (google.com: domain of linux-kernel+bounces-156518-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99;
Message-ID: <7122785c-d6cf-4425-82a5-2f65e0a523d9@quicinc.com>
Date: Wed, 24 Apr 2024 13:29:21 +0530
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH v1] arm64: dts: qcom: sc7280: Remove CTS/RTS configuration
Content-Language: en-US
To: Luca Weiss <luca.weiss@fairphone.com>,
        <cros-qcom-dts-watchers@chromium.org>, <andersson@kernel.org>,
        <konrad.dybcio@linaro.org>, <swboyd@chromium.org>, <robh@kernel.org>,
        <krzk+dt@kernel.org>, <linux-arm-msm@vger.kernel.org>,
        <conor+dt@kernel.org>, <devicetree@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <rajpat@codeaurora.org>,
        <mka@chromium.org>, <rojay@codeaurora.org>
CC: <quic_msavaliy@quicinc.com>, <quic_anupkulk@quicinc.com>
References: <20240416105650.2626-1-quic_vdadhani@quicinc.com>
 <D0LINETM8WNA.27BORT75W1N0C@fairphone.com>
From: Viken Dadhaniya <quic_vdadhani@quicinc.com>
In-Reply-To: <D0LINETM8WNA.27BORT75W1N0C@fairphone.com>
Content-Type: text/plain; charset="UTF-8"; format=flowed
Content-Transfer-Encoding: 7bit


On 4/16/2024 5:08 PM, Luca Weiss wrote:
> On Tue Apr 16, 2024 at 12:56 PM CEST, Viken Dadhaniya wrote:
>> Remove CTS and RTS pinctrl configuration for UART5 node as
>> it's designed for debug UART for all the board variants of the
>> sc7280 chipset.
>>
>> Also change compatible string to debug UART.
> 
> This change has little to do with the SoC design though and is dependent
> on the usage on a given board, right? Also the QCM6490 datasheet
> mentions gpio21 & gpio22 can be used for UART_CTS and UART_RFR.
> 
> But at least consistency-wise this change makes sense, in practically
> all other SoCs one UART is marked as geni-debug-uart.
> 
> But with this patch you should then also remove some overrides that are
> placed in various boards already?
> 
> arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts:     compatible = "qcom,geni-debug-uart";
> arch/arm64/boot/dts/qcom/qcm6490-idp.dts:       compatible = "qcom,geni-debug-uart";
> arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts:   compatible = "qcom,geni-debug-uart";
> arch/arm64/boot/dts/qcom/sc7280-idp.dtsi:       compatible = "qcom,geni-debug-uart";
> arch/arm64/boot/dts/qcom/sc7280-qcard.dtsi:     compatible = "qcom,geni-debug-uart";
> 
> Regards
> Luca
> 

Updated in V2.

>>
>> Fixes: 38cd93f413fd ("arm64: dts: qcom: sc7280: Update QUPv3 UART5 DT node")
>> Signed-off-by: Viken Dadhaniya <quic_vdadhani@quicinc.com>
>> ---
>>   arch/arm64/boot/dts/qcom/sc7280.dtsi | 14 ++------------
>>   1 file changed, 2 insertions(+), 12 deletions(-)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/sc7280.dtsi b/arch/arm64/boot/dts/qcom/sc7280.dtsi
>> index 38c183b2bb26..2a6b4c4639d1 100644
>> --- a/arch/arm64/boot/dts/qcom/sc7280.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/sc7280.dtsi
>> @@ -1440,12 +1440,12 @@
>>   			};
>>   
>>   			uart5: serial@994000 {
>> -				compatible = "qcom,geni-uart";
>> +				compatible = "qcom,geni-debug-uart";
>>   				reg = <0 0x00994000 0 0x4000>;
>>   				clocks = <&gcc GCC_QUPV3_WRAP0_S5_CLK>;
>>   				clock-names = "se";
>>   				pinctrl-names = "default";
>> -				pinctrl-0 = <&qup_uart5_cts>, <&qup_uart5_rts>, <&qup_uart5_tx>, <&qup_uart5_rx>;
>> +				pinctrl-0 = <&qup_uart5_tx>, <&qup_uart5_rx>;
>>   				interrupts = <GIC_SPI 606 IRQ_TYPE_LEVEL_HIGH>;
>>   				power-domains = <&rpmhpd SC7280_CX>;
>>   				operating-points-v2 = <&qup_opp_table>;
>> @@ -5397,16 +5397,6 @@
>>   				function = "qup04";
>>   			};
>>   
>> -			qup_uart5_cts: qup-uart5-cts-state {
>> -				pins = "gpio20";
>> -				function = "qup05";
>> -			};
>> -
>> -			qup_uart5_rts: qup-uart5-rts-state {
>> -				pins = "gpio21";
>> -				function = "qup05";
>> -			};
>> -
>>   			qup_uart5_tx: qup-uart5-tx-state {
>>   				pins = "gpio22";
>>   				function = "qup05";
>