From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CCA7C2D0A3 for ; Fri, 30 Oct 2020 01:18:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C3FB220739 for ; Fri, 30 Oct 2020 01:18:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="QamlEIUF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726238AbgJ3BSG (ORCPT ); Thu, 29 Oct 2020 21:18:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726156AbgJ3BSD (ORCPT ); Thu, 29 Oct 2020 21:18:03 -0400 Received: from mail-pl1-x641.google.com (mail-pl1-x641.google.com [IPv6:2607:f8b0:4864:20::641]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20FF9C0613CF for ; Thu, 29 Oct 2020 18:18:03 -0700 (PDT) Received: by mail-pl1-x641.google.com with SMTP id t22so2162162plr.9 for ; Thu, 29 Oct 2020 18:18:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:content-transfer-encoding:in-reply-to:references :subject:from:cc:to:date:message-id:user-agent; bh=6/T1bgNMX0hc7obLwVMGSAc+uvcAnq6mB6Znj0RpZj4=; b=QamlEIUF04NHqrdOLu3HlEqGIxbCZMTeDWZLaOyYYaIwjgG8bPGY97mDz5SRffykgk 2LM0B+k0EopunO8G3uCNnT2utfRb2DJLAu5QC2Rr5GXAS4KCAIj2l99cM+qo0uSjUUyW pSDHp/0eK9Ihzh/cFLxsrz3uNL+EFPjLYL9fw= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:content-transfer-encoding :in-reply-to:references:subject:from:cc:to:date:message-id :user-agent; bh=6/T1bgNMX0hc7obLwVMGSAc+uvcAnq6mB6Znj0RpZj4=; b=mQB/UDOBUbaBxtqpXy9sBOKaDyLn2+3QhdWYXeis1KrHt6GqoqNu39eJriiwOoVb7S vXYR/DGHr+8dPVjr6ftfvX/YBOO0Q6kosNy4LWdF6Kloe40LtVknwgcF3rW8HYZp0fhp m6cKFcrfSXjV2qK6JpA6MsYNSECZbWV8/BJOzu7SMtUkD4rt5ucl/kR2kZQpP2MEf5FZ dkHEWzghtkfZItWhF2ONukaSfd/2bevgR1NAcAFQsPk4TqHYUKj9sbNjB4ym3tP2o0pR CIvwa0vrhbnOJi3EYnUfro8I/570akd+3v2JGHxe5PqBNI0GDwtdGKu1P/sNjYEGeyt3 ctrw== X-Gm-Message-State: AOAM532t8mhDrOFtL1WiID47M3N1njzoW0722/NEGAtsqdfoNYxw8v4G JzXBxZrTekGTvQhVUYVKQCEK+yftxt/ZYg== X-Google-Smtp-Source: ABdhPJzZFC3ctMbDZuoSYzO/annVO2MRDdW3xmvpRDz3KMTE+zxuQLBGDVnn8zI8L/vzvVOAlnwIYg== X-Received: by 2002:a17:902:780f:b029:d6:3413:9fe8 with SMTP id p15-20020a170902780fb02900d634139fe8mr6827287pll.46.1604020682572; Thu, 29 Oct 2020 18:18:02 -0700 (PDT) Received: from chromium.org ([2620:15c:202:201:3e52:82ff:fe6c:83ab]) by smtp.gmail.com with ESMTPSA id a10sm1061409pjq.17.2020.10.29.18.18.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 29 Oct 2020 18:18:01 -0700 (PDT) Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable In-Reply-To: <20201029011154.1515687-2-swboyd@chromium.org> References: <20201029011154.1515687-1-swboyd@chromium.org> <20201029011154.1515687-2-swboyd@chromium.org> Subject: Re: [PATCH 1/4] drm/bridge: ti-sn65dsi86: Combine register accesses in ti_sn_aux_transfer() From: Stephen Boyd Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Douglas Anderson , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Sean Paul To: Andrzej Hajda , Neil Armstrong Date: Thu, 29 Oct 2020 18:18:00 -0700 Message-ID: <160402068056.884498.17274332256355831549@swboyd.mtv.corp.google.com> User-Agent: alot/0.9.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Quoting Stephen Boyd (2020-10-28 18:11:51) > @@ -72,6 +74,7 @@ > #define SN_AUX_ADDR_19_16_REG 0x74 > #define SN_AUX_ADDR_15_8_REG 0x75 > #define SN_AUX_ADDR_7_0_REG 0x76 > +#define SN_AUX_ADDR_MASK GENMASK(19, 0) > #define SN_AUX_LENGTH_REG 0x77 > #define SN_AUX_CMD_REG 0x78 > #define AUX_CMD_SEND BIT(0) > @@ -841,11 +844,13 @@ static ssize_t ti_sn_aux_transfer(struct drm_dp_aux= *aux, > struct ti_sn_bridge *pdata =3D aux_to_ti_sn_bridge(aux); > u32 request =3D msg->request & ~DP_AUX_I2C_MOT; > u32 request_val =3D AUX_CMD_REQ(msg->request); > - u8 *buf =3D (u8 *)msg->buffer; > + u8 *buf =3D msg->buffer; > + unsigned int len =3D msg->size; > unsigned int val; > - int ret, i; > + int ret; > + u8 addr_len[SN_AUX_LENGTH_REG + 1 - SN_AUX_ADDR_19_16_REG]; I realize now that the SN_AUX_CMD_REG is also here and it has a "go bit" in it. We can combine another register write here by writing out the address, length, and request in one go. I rolled that into v2.