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
References: <1606746513-30909-1-git-send-email-kevin3.tang@gmail.com> <1606746513-30909-2-git-send-email-kevin3.tang@gmail.com>
In-Reply-To: <1606746513-30909-2-git-send-email-kevin3.tang@gmail.com>
From:   Rob Herring <robh+dt@kernel.org>
Date:   Mon, 30 Nov 2020 13:29:06 -0700
Message-ID: <CAL_Jsq+fC1TzygUopiwVtwBN8JtwmnGy=VMTEvkudSQUdXiMqg@mail.gmail.com>
Subject: Re: [PATCH 1/6] dt-bindings: display: add Unisoc's drm master bindings
To:     Kevin Tang <kevin3.tang@gmail.com>
Cc:     Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Mark Rutland <mark.rutland@arm.com>,
        Orson Zhai <orsonzhai@gmail.com>,
        Lyra Zhang <zhang.lyra@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        dri-devel <dri-devel@lists.freedesktop.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Mon, Nov 30, 2020 at 7:28 AM Kevin Tang <kevin3.tang@gmail.com> wrote:
>
> From: Kevin Tang <kevin.tang@unisoc.com>

Once again, DT patches must Cc the DT list if you want them reviewed.

>
> The Unisoc DRM master device is a virtual device needed to list all
> DPU devices or other display interface nodes that comprise the
> graphics subsystem
>
> Cc: Orson Zhai <orsonzhai@gmail.com>
> Cc: Chunyan Zhang <zhang.lyra@gmail.com>
> Signed-off-by: Kevin Tang <kevin.tang@unisoc.com>
> ---
>  .../display/sprd/sprd,display-subsystem.yaml       | 39 ++++++++++++++++++++++
>  1 file changed, 39 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/sprd/sprd,display-subsystem.yaml
>
> diff --git a/Documentation/devicetree/bindings/display/sprd/sprd,display-subsystem.yaml b/Documentation/devicetree/bindings/display/sprd/sprd,display-subsystem.yaml
> new file mode 100644
> index 0000000..9487a39
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/sprd/sprd,display-subsystem.yaml
> @@ -0,0 +1,39 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/sprd/sprd,display-subsystem.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Unisoc DRM master device
> +
> +maintainers:
> +  - Kevin Tang <kevin.tang@unisoc.com>
> +
> +description: |
> +  The Unisoc DRM master device is a virtual device needed to list all
> +  DPU devices or other display interface nodes that comprise the
> +  graphics subsystem.
> +
> +properties:
> +  compatible:
> +    const: sprd,display-subsystem

As I said before, we try to avoid these virtual nodes. Make the DRM
driver bind to the DPU node.

The case where this might be needed is if you have h/w that's a
mixture of shared and discrete blocks. I don't see anything here
matching that.

Rob