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Message-ID: <5b6d4cfd-dedb-3123-9db4-28e202da11b2@denx.de>
Date:   Mon, 17 Apr 2023 00:12:29 +0200
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Subject: Re: [PATCH 4/6] drm: bridge: samsung-dsim: Dynamically configure DPHY
 timing
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To:     Adam Ford <aford173@gmail.com>, dri-devel@lists.freedesktop.org
Cc:     m.szyprowski@samsung.com, aford@beaconembedded.com,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Shawn Guo <shawnguo@kernel.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>,
        Inki Dae <inki.dae@samsung.com>,
        Jagan Teki <jagan@amarulasolutions.com>,
        Andrzej Hajda <andrzej.hajda@intel.com>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Robert Foss <rfoss@kernel.org>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        Jonas Karlman <jonas@kwiboo.se>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Frieder Schrempf <frieder.schrempf@kontron.de>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
References: <20230415104104.5537-1-aford173@gmail.com>
 <20230415104104.5537-4-aford173@gmail.com>
From:   Marek Vasut <marex@denx.de>
In-Reply-To: <20230415104104.5537-4-aford173@gmail.com>
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On 4/15/23 12:41, Adam Ford wrote:
> NXP uses a lookup table to determine the various values for
> the PHY Timing based on the clock rate in their downstream
> kernel.  Since the input clock can be variable, the phy
> settings need to be variable too.  Add an additional variable
> to the driver data to enable this feature to prevent breaking
> boards that don't support it.

Isn't there already a generic LP2HS transition time calculation in the 
kernel ?

This looks like a generic calculation which should be done by all the 
DSI hosts, so why not introduce a generic helper to do such a 
calculation (and not a table please) ?