Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
In-Reply-To: <5adf2ab2c2a162272509d253bd797721@codeaurora.org>
References: <1629282424-4070-1-git-send-email-mkrishn@codeaurora.org>
 <1629282424-4070-2-git-send-email-mkrishn@codeaurora.org> <CAE-0n50b=pX=1MFwGPDvDR=O03tUAkAgyMonGm2+SXBft=16KQ@mail.gmail.com>
 <5adf2ab2c2a162272509d253bd797721@codeaurora.org>
From:   Stephen Boyd <swboyd@chromium.org>
User-Agent: alot/0.9.1
Date:   Thu, 30 Sep 2021 10:58:26 -0700
Message-ID: <CAE-0n53kQU=8pdcWR0OZap1wDgxxwed0qvfaGruc71YT5Cj1iA@mail.gmail.com>
Subject: Re: [PATCH v1 2/4] arm64: dts: qcom: sc7280: add display dt nodes
To:     mkrishn@codeaurora.org
Cc:     devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        linux-kernel@vger.kernel.org, kalyan_t@codeaurora.org,
        sbillaka@codeaurora.org, abhinavk@codeaurora.org,
        robdclark@gmail.com, bjorn.andersson@linaro.org,
        khsieh@codeaurora.org, rajeevny@codeaurora.org,
        freedreno@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
        robh+dt@kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Quoting mkrishn@codeaurora.org (2021-09-30 04:56:59)
> On 2021-08-19 01:27, Stephen Boyd wrote:
> > Quoting Krishna Manikandan (2021-08-18 03:27:02)
> >> diff --git a/arch/arm64/boot/dts/qcom/sc7280.dtsi
> >> b/arch/arm64/boot/dts/qcom/sc7280.dtsi
> >> index 53a21d0..fd7ff1c 100644
> >> --- a/arch/arm64/boot/dts/qcom/sc7280.dtsi
> >> +++ b/arch/arm64/boot/dts/qcom/sc7280.dtsi
> >> +
> >> +                       status = "disabled";
> >> +
> >> +                       mdp: mdp@ae01000 {
> >
> > display-controller@ae01000
>
> Stephen,
>     In the current driver code, there is a substring comparison for "mdp"
> in device node name as part of probe sequence. If "mdp" is not present
> in the node name, it will
>     return an error resulting in probe failure. Can we continue using mdp
> as nodename instead of display controller?
>

Can we fix the driver to not look for node names and look for compatible
strings instead? It took me a minute to find compare_name_mdp() in
drivers/gpu/drm/msm/msm_drv.c to understand what you're talking about.
Perhaps looking for qcom,mdp5 in there will be sufficient instead of
looking at the node name.