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b=FeVUCQuoAJzqley7wA7CxjwDJvMnr8XnIf61RSUbXvYFOPI4e/7Eh4I+EMOvSmoqVoH3LVyS98vc3sfbk57bNbw+QNfFOFXUewV946+pUEyaWGPtJp9z4KaCegHGEUa9TrVA3VOEEVJR/f1LgbiaDeOG2rUIxjYRLUrQuE0qo4M= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nxp.com; Received: from AM7PR04MB7046.eurprd04.prod.outlook.com (2603:10a6:20b:113::22) by DB9PR04MB9404.eurprd04.prod.outlook.com (2603:10a6:10:368::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6002.33; Thu, 26 Jan 2023 02:11:12 +0000 Received: from AM7PR04MB7046.eurprd04.prod.outlook.com ([fe80::5725:92ec:f43e:f5fc]) by AM7PR04MB7046.eurprd04.prod.outlook.com ([fe80::5725:92ec:f43e:f5fc%7]) with mapi id 15.20.6002.028; Thu, 26 Jan 2023 02:11:12 +0000 Message-ID: <4ec549dcec8686b9d1eed619965fde0b17736f17.camel@nxp.com> Subject: Re: [PATCH v2 2/6] drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge From: Liu Ying To: Marek Vasut , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: stefan@agner.ch, airlied@gmail.com, daniel@ffwll.ch, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com, krzysztof.kozlowski@linaro.org, LW@KARO-electronics.de, alexander.stein@ew.tq-group.com Date: Thu, 26 Jan 2023 10:10:38 +0800 In-Reply-To: References: <20230125064030.1222121-1-victor.liu@nxp.com> <20230125064030.1222121-3-victor.liu@nxp.com> Content-Type: text/plain; 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Drop > > the unnecessary NULL pointer check in KMS stage. > > Is it possible that a panel (instead of a bridge) be attached to > LCDIFv3 > e.g. in case of iMXRT ? According to IMXRT1160 and IMXRT1170 reference manuals, it looks like LCDIFv2(similar to LCDIFv3, but not the same) may connect to a parallel display panel through a mux(either eLCDIF or LCDIFv2). That mux could be a bridge. But, it doesn't matter, because devm_drm_of_get_bridge() may create a panel bridge if a panel is connected directly(See kerneldoc of devm_drm_of_get_bridge()). Regards, Liu Ying > > > Signed-off-by: Liu Ying > > --- > > v1->v2: > > * Split from patch 2/2 in v1. (Marek, Alexander) > > Much appreciated, thanks. > > [...]