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Brown" Subject: Re: [PATCH RESEND v4 4/4] drm/bridge: nwl-dsi: Correct MIPI DSI horizontal sync timing Message-ID: References: <20261014-nwl-dsi-fixes-v4-0-b9138ea5e12c@geanix.com> <20261014-nwl-dsi-fixes-v4-4-b9138ea5e12c@geanix.com> <179207245898.1117464.4430806907649454372.b4-review@b4> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <179207245898.1117464.4430806907649454372.b4-review@b4> X-ClientProxiedBy: BY3PR04CA0018.namprd04.prod.outlook.com (2603:10b6:a03:217::23) To GV2PR04MB11799.eurprd04.prod.outlook.com (2603:10a6:150:2cf::9) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: GV2PR04MB11799:EE_|MI9PR04MB991975:EE_ X-MS-Office365-Filtering-Correlation-Id: 75953015-7006-48ba-c87f-08df2acf923e X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; ARA:13230040|19092799006|1800799024|376014|366016|7416014|23010399003|56012099006|11063799006|4143699003|10067099003|22082099003|18002099003; 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The formula shown there does not take packet header size > > into account though. > > > > The formula implemented here converts the hfp, hsa, and hbp to DSI packet > > bytes and then subtracts the number of packet header bytes. > > > > It is worth noting that these values only needs to match approximately, > > according to the reference manual. > > > > Based on commit in NXP vendor tree > > commit f2a61699749d ("LF-7981-4: drm/bridge: nwl-dsi: Correct MIPI DSI horizontal sync timing") > > > > Signed-off-by: Esben Haabendal > > Cc: Robert Chiras > > Cc: Oliver F. Brown > > It would be great to have this reviewed by someone at NXP. > > @Frank, do you think you can help with this? Let me talk with oliver, I am not familar with this part. Frank > > On my side I don't know the hardware and didn't check the maths > implemented. Still LGTM: > Reviewed-by: Luca Ceresoli > > -- > Luca Ceresoli, Bootlin > Embedded Linux and Kernel engineering > https://bootlin.com >