From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E829C1991D2; Fri, 16 Aug 2024 12:24:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723811079; cv=none; b=Z95qJFx4yBf5hEgGxFyByuTWfvTVsen0x0STNbcwcLRWIOJZQEiip4KZZGP3Wym8FwalP6D10JsKjY69IOXMGaL7+IppneoNoRBCNfUT+Ako9YBRkKdK5ZXeGIp1NANYhCoNZ0OnK1ACP8WdHW6+i6HjKUCa3l8uFDQn7T+AHzQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723811079; c=relaxed/simple; bh=BHvv3tQ/qH7itDrWANJ9OnwJU3uS5u76IJ2JNjIhTqM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=UGCIqot+ixAgCYiOa7rUpnPqrmEP4O8spyEVCd3n3QXX94diWEHZDb3VzlTEjQ4HFPlJnrcNBgxkcTcU/cpFilv4p0gqOmFG4K2NaOw39eNXKm4+PbG64Vhl/woJcZ5EkG3cCmbIiUydpKet1xBNbZPCw5UrCuWCy4QSFC4behI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=u4K44YJF; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="u4K44YJF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0982BC32782; Fri, 16 Aug 2024 12:24:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1723811078; bh=BHvv3tQ/qH7itDrWANJ9OnwJU3uS5u76IJ2JNjIhTqM=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=u4K44YJF2Qc1nQLB8q3V8ADeGVb2TyoGJv2zIL7cfKS3KqZJ0zkIdMFSYyla2KOmL hzw162U3RzlB5v4XhilnoFD4feol2Vic/anaTfK7+qHF+2iYG1SjPioz87hgHdRgaZ aBQC1jy693cWkpivc9o0Nwu0+/jJn5LajFiUd8QeqB/HMYOZTDAjyZjle8boa2Ln7w pzBF9FfH9LdV2giP2tWEPu5EHGM/tVFegQoRTjaBHDjO588tsEQoCwVCKoklWUwUxc oM2SvxwuU2r6un731UcP3m+vUF3bqpLjoPATnxZHFKIk0uuNbHT4vNlRfc8OurOf6T o0yapb+Z50NHQ== Message-ID: Date: Fri, 16 Aug 2024 14:24:28 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 RESEND 2/2] drm/bridge: imx: Add i.MX93 parallel display format configuration support To: Liu Ying , devicetree@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Cc: robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, daniel@ffwll.ch, peng.fan@nxp.com References: <20240816080933.440594-1-victor.liu@nxp.com> <20240816080933.440594-3-victor.liu@nxp.com> <613b4eb4-dbac-48a9-bcdd-79b4e94a7b66@nxp.com> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 16/08/2024 11:44, Liu Ying wrote: > On 08/16/2024, Krzysztof Kozlowski wrote: >> On 16/08/2024 10:09, Liu Ying wrote: >>> NXP i.MX93 mediamix blk-ctrl contains one DISPLAY_MUX register which >>> configures parallel display format by using the "PARALLEL_DISP_FORMAT" >>> field. Add a DRM bridge driver to support the display format configuration. >>> >>> Signed-off-by: Liu Ying >>> --- >> >> ... >> >>> + >>> +static int imx93_pdfc_bridge_probe(struct platform_device *pdev) >>> +{ >>> + struct device *dev = &pdev->dev; >>> + struct imx93_pdfc *pdfc; >>> + int ret; >>> + >>> + pdfc = devm_kzalloc(dev, sizeof(*pdfc), GFP_KERNEL); >>> + if (!pdfc) >>> + return -ENOMEM; >>> + >>> + pdfc->regmap = syscon_node_to_regmap(dev->of_node->parent); >>> + if (IS_ERR(pdfc->regmap)) { >>> + ret = PTR_ERR(pdfc->regmap); >>> + if (ret != -EPROBE_DEFER) >>> + DRM_DEV_ERROR(dev, "failed to get regmap: %d\n", ret); >>> + return ret; >> >> Nope, you just open-coded dev_err_probe. Syntax is - return >> dev_err_probe(). if you need wrapper for DRM, add such. > > Will use dev_err_probe(). > >> >>> + } >>> + >>> + pdfc->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0); >>> + if (IS_ERR(pdfc->next_bridge)) { >>> + ret = PTR_ERR(pdfc->next_bridge); >>> + if (ret != -EPROBE_DEFER) >>> + DRM_DEV_ERROR(dev, "failed to get next bridge: %d\n", ret); >>> + return ret; >> >> Ditto > > Will use dev_err_probe(). > >> >> >>> + } >>> + >> >> ... >> >>> +MODULE_DESCRIPTION("NXP i.MX93 parallel display format configuration driver"); >>> +MODULE_AUTHOR("Liu Ying "); >>> +MODULE_LICENSE("GPL v2"); >>> +MODULE_ALIAS("platform:" DRIVER_NAME); >> >> Which other driver needs this platform alias? > > Quote include/linux/module.h: > > " > /* For userspace: you can also call me... */ > #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias) > " > > Anything wrong with using MODULE_ALIAS() here? Yes, it redundant. Do not answer with question to the question. Are you adding random code that you cannot justify? It looks like this if you cannot answer why do you need it. Form letter: You should not need MODULE_ALIAS() in normal cases. If you need it, usually it means your device ID table is wrong (e.g. misses either entries or MODULE_DEVICE_TABLE()). MODULE_ALIAS() is not a substitute for incomplete ID table. Best regards, Krzysztof