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From:   Adam Ford <aford173@gmail.com>
Date:   Sat, 13 May 2023 23:23:04 -0500
Message-ID: <CAHCN7x+evo1mJaBUdx5pe5rnG2A8dkmf4myXJcK7mas7nZMwxg@mail.gmail.com>
Subject: Re: [PATCH V2] arm64: dts: imx8mn: Fix video clock parents
To:     Shawn Guo <shawnguo@kernel.org>
Cc:     linux-arm-kernel@lists.infradead.org, aford@beaconembedded.com,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        Marek Vasut <marex@denx.de>, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
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On Sat, May 13, 2023 at 10:58=E2=80=AFPM Shawn Guo <shawnguo@kernel.org> wr=
ote:
>
> On Sun, Apr 23, 2023 at 07:35:13AM -0500, Adam Ford wrote:
> > There are a few clocks whose parents are set in mipi_dsi
> > and mxsfb nodes, but these clocks are used by the disp_blk_ctrl
> > power domain which may cause an issue when re-parenting, resuling
> > in a disp_pixel clock having the wrong parent and wrong rate.
> >
> > Fix this by moving the assigned-clock-parents as associate clock
> > assignments to the power-domain node to setup these clocks before
> > they are enabled.
> >
> > Fixes: d825fb6455d5 ("arm64: dts: imx8mn: Add display pipeline componen=
ts")
> > Signed-off-by: Adam Ford <aford173@gmail.com>
>
> Is it a fix for v6.4-rc or material for -next?

The Samsung DSI driver for Nano is in 6.4, and an attempt was made to
setup the device tree in 6.4.  While I don't think there are users of
this yet, if people try to add DT entries in their boards, they might
struggle getting the video working if this isn't applied since the
disp1_pix clock may be stuck at 24MHz which likely won't sync much if
any displays.

adam
>
> Shawn