[{"id":3683989,"web_url":"http://patchwork.ozlabs.org/comment/3683989/","msgid":"","list_archive_url":null,"date":"2026-04-29T10:49:55","subject":"Re: [PATCH] staging: tegra-video: replace bit shifts with BIT()\n macro","submitter":{"id":83908,"url":"http://patchwork.ozlabs.org/api/people/83908/","name":"Luca Ceresoli","email":"luca.ceresoli@bootlin.com"},"content":"On Tue Apr 28, 2026 at 6:33 PM CEST, Mhanna112-code wrote:\n> Replace manual bit shifts with the BIT() macro to follow kernel\n> coding style and improve readability.\n>\n> Fixes the following checkpatch warning:\n>\n> CHECK: Prefer using the BIT macro\n>\n> Signed-off-by: Marc Hanna \n> ---\n> drivers/staging/media/tegra-video/tegra20.c | 6 +++---\n> 1 file changed, 3 insertions(+), 3 deletions(-)\n>\n> diff --git a/drivers/staging/media/tegra-video/tegra20.c b/drivers/staging/media/tegra-video/tegra20.c\n> index eb1fc5b7e2cd..f3edca909684 100644\n> --- a/drivers/staging/media/tegra-video/tegra20.c\n> +++ b/drivers/staging/media/tegra-video/tegra20.c\n> @@ -177,15 +177,15 @@ enum tegra_vi_out {\n> #define CSI_SKIP_PACKET_THRESHOLD(n)\t\t(((n) & 0xff) << 16)\n> #define TEGRA_CSI_PIXEL_STREAM_CONTROL0(n)\t\t(0x0018 + (n) * 0x2c)\n> #define CSI_PP_PAD_FRAME_PAD0S\t\t\t(0 << 28)\n> -#define CSI_PP_PAD_FRAME_PAD1S\t\t\t(1 << 28)\n> +#define CSI_PP_PAD_FRAME_PAD1S\t\t\tBIT(28)\n> #define CSI_PP_PAD_FRAME_NOPAD\t\t\t(2 << 28)\n> #define CSI_PP_HEADER_EC_ENABLE\t\t\tBIT(27)\n> #define CSI_PP_PAD_SHORT_LINE_PAD0S\t\t(0 << 24)\n> -#define CSI_PP_PAD_SHORT_LINE_PAD1S\t\t(1 << 24)\n> +#define CSI_PP_PAD_SHORT_LINE_PAD1S\t\tBIT(24)\n> #define CSI_PP_PAD_SHORT_LINE_NOPAD\t\t(2 << 24)\n> #define CSI_PP_EMBEDDED_DATA_EMBEDDED\t\tBIT(20)\n> #define CSI_PP_OUTPUT_FORMAT_ARBITRARY\t\t(0 << 16)\n> -#define CSI_PP_OUTPUT_FORMAT_PIXEL\t\t(1 << 16)\n> +#define CSI_PP_OUTPUT_FORMAT_PIXEL\t\tBIT(16)\n> #define CSI_PP_OUTPUT_FORMAT_PIXEL_REP\t\t(2 << 16)\n> #define CSI_PP_OUTPUT_FORMAT_STORE\t\t(3 << 16)\n> #define CSI_PP_VIRTUAL_CHANNEL_ID(n)\t\t(((n) - 1) << 14)\n\nI think this change would make code worse, not better. These look like\nenum-like values for 2-bit register fields, and as such should be described\nthe same way for readability.\n\nIf we want to change them they should perhaps use a GENMASK or similar, but\nit probably makes sense to just leave them as is. They are mostly unused\nanyway.\n\nLuca\n\n--\nLuca Ceresoli, Bootlin\nEmbedded Linux and Kernel engineering\nhttps://bootlin.com","headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linux-tegra@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=bootlin.com header.i=@bootlin.com header.a=rsa-sha256\n header.s=dkim header.b=bqtEgdOR;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c09:e001:a7::12fc:5321; helo=sto.lore.kernel.org;\n envelope-from=linux-tegra+bounces-14058-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)","smtp.subspace.kernel.org;\n\tdkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com\n header.b=\"bqtEgdOR\"","smtp.subspace.kernel.org;\n arc=none smtp.client-ip=185.246.85.4","smtp.subspace.kernel.org;\n dmarc=pass (p=reject dis=none) header.from=bootlin.com","smtp.subspace.kernel.org;\n spf=pass smtp.mailfrom=bootlin.com"],"Received":["from sto.lore.kernel.org (sto.lore.kernel.org\n [IPv6:2600:3c09:e001:a7::12fc:5321])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4g5DbL4Wg9z1yHX\n\tfor ; Wed, 29 Apr 2026 20:50:06 +1000 (AEST)","from smtp.subspace.kernel.org (conduit.subspace.kernel.org\n [100.90.174.1])\n\tby sto.lore.kernel.org (Postfix) with ESMTP id B9EFC30059AB\n\tfor ; Wed, 29 Apr 2026 10:50:02 +0000 (UTC)","from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id 6CCD63EF0C4;\n\tWed, 29 Apr 2026 10:50:02 +0000 (UTC)","from smtpout-03.galae.net (smtpout-03.galae.net [185.246.85.4])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby smtp.subspace.kernel.org (Postfix) with ESMTPS id 12BBC3EB7F0\n\tfor ; Wed, 29 Apr 2026 10:49:59 +0000 (UTC)","from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233])\n\tby smtpout-03.galae.net (Postfix) with ESMTPS id 8B1454E42AED;\n\tWed, 29 Apr 2026 10:49:58 +0000 (UTC)","from mail.galae.net (mail.galae.net [212.83.136.155])\n\tby smtpout-01.galae.net (Postfix) with ESMTPS id 577EC601DF;\n\tWed, 29 Apr 2026 10:49:58 +0000 (UTC)","from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon)\n with ESMTPSA id 1178910729835;\n\tWed, 29 Apr 2026 12:49:55 +0200 (CEST)"],"ARC-Seal":"i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1777459802; cv=none;\n b=c+n1/ySQ+Zvevvcu8BYa/leVdZLSWRbATALF4zLjxA0VaO/was9mPFxBTca1Z4FaN/Qb8q0u/+E88QjLjfUyrAF2nn45bET44iX5oFKodT+Z90Su6xuy/HJEXoUQaPts2UZN+ObtEx7KO3e07o6aMOEAW5wFW+hl0hRCfDei6y0=","ARC-Message-Signature":"i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1777459802; c=relaxed/simple;\n\tbh=Oh/Ob5Y/L8o14cR6ZoVlhC9Kq0oV/DMTyaQSm/rDuWU=;\n\th=Mime-Version:Content-Type:Date:Message-Id:Subject:Cc:To:From:\n\t References:In-Reply-To;\n b=YMdsuXlYr9ma+4YulyDaBJXahpVecXPclvoGRzn5K9DuuNBVmTaRoHzVON+jo8HqZqnYrhmmZRiVxvM3scNhnHFzJzUtmsh3Yd9fYm49SxXMwWc04ZVQnR5LvrTG4tcrTZ1AoCjdM3igBwd653g3+P+3Ade2cRNoUBzMmIpGxaM=","ARC-Authentication-Results":"i=1; smtp.subspace.kernel.org;\n dmarc=pass (p=reject dis=none) header.from=bootlin.com;\n spf=pass smtp.mailfrom=bootlin.com;\n dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com\n header.b=bqtEgdOR; arc=none smtp.client-ip=185.246.85.4","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim;\n\tt=1777459797; h=from:subject:date:message-id:to:cc:mime-version:content-type:\n\t content-transfer-encoding:in-reply-to:references;\n\tbh=WXbajj9BBIsUoAggvYIZsmgmbeeRvJ4lzJfq8wHWrnM=;\n\tb=bqtEgdORUNeErEiYzN2IAtMlvp2mklDRGorR7bsrVZWoGfMhzWvPDoa3ciPplfC9n7DJdJ\n\tzbaOQtR3qe7R0gd5VVcBiV/5clg7uC/XNCWCdY0ve9NqYjPc4tavSHsJh+KjkkSmurlPQh\n\tdz8Rz3ZYiX38Qm+0fAyh1XuxOn+Jq0Hct8Nse1AqIrrK68f9uZX1sq9HZxS/u9AgRReVZP\n\te3Lk7rELors7g6uTYydPl0noWzJD3enkS/SA/CVgNdunCA04/JVL/CO6qWhd9PJ/C/U6I3\n\tAoZeQ76EGV2j+Q6AIBr9cqUHoUglsAASMt2Ulo+Qkug4MEjp8OzYhkvGooB8oA==","Precedence":"bulk","X-Mailing-List":"linux-tegra@vger.kernel.org","List-Id":"","List-Subscribe":"","List-Unsubscribe":"","Mime-Version":"1.0","Content-Transfer-Encoding":"quoted-printable","Content-Type":"text/plain; charset=UTF-8","Date":"Wed, 29 Apr 2026 12:49:55 +0200","Message-Id":"","Subject":"Re: [PATCH] staging: tegra-video: replace bit shifts with BIT()\n macro","Cc":", ,\n , ,\n , ,\n , ","To":"\"Mhanna112-code\" ,\n ","From":"\"Luca Ceresoli\" ","X-Mailer":"aerc 0.20.1","References":"<20260428163312.7374-1-marchanna111@gmail.com>","In-Reply-To":"<20260428163312.7374-1-marchanna111@gmail.com>","X-Last-TLS-Session-Version":"TLSv1.3"}}]