From patchwork Fri Apr 4 19:58:38 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Alex Deucher X-Patchwork-Id: 3940641 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id E0F989F370 for ; Fri, 4 Apr 2014 19:58:53 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1972D203E3 for ; Fri, 4 Apr 2014 19:58:53 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 045A2203E1 for ; Fri, 4 Apr 2014 19:58:51 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 818F26EDF5; Fri, 4 Apr 2014 12:58:49 -0700 (PDT) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-qc0-f169.google.com (mail-qc0-f169.google.com [209.85.216.169]) by gabe.freedesktop.org (Postfix) with ESMTP id 302326EDF0 for ; Fri, 4 Apr 2014 12:58:46 -0700 (PDT) Received: by mail-qc0-f169.google.com with SMTP id i17so4078043qcy.0 for ; Fri, 04 Apr 2014 12:58:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-type:content-transfer-encoding; bh=v5Fpq/6TkvAxtnjDoGwloZmVi0vx8QiJm2dncH2JTGA=; b=b0Ci1JyG1ud8vVx2J8L03y/ZdsyTt1WKfc9R5Xl0OX1Pptzfl5G0ty6jWpZhCJgnei OOk1ATs14aHAk8yrcr0OYbAr7VBmQmU3Q9gJOIGkkq0mBTO1MN1sP75TsoKSwVTFRsOs aWaqp+1uu8nyPloH2HMJP89ynJ8S2VbsdmdNe1ERyJrNzwy5TG4lTizUOht8fqlBoOS9 oIx3qN6WGb9btTrF9eqa2YYk9Hd1juG5YKl9PWP3loswEinlG+3BYYZvRx/itRwa3c71 azVcuDGosOkt4GnAJbXq7+7AmoZcXFy2Ja8MK+xM5VvBDXWjIT7MhjRG6YrHiuHQsed4 42iA== X-Received: by 10.140.97.8 with SMTP id l8mr16216488qge.19.1396641525695; Fri, 04 Apr 2014 12:58:45 -0700 (PDT) Received: from localhost.localdomain (static-74-96-105-49.washdc.fios.verizon.net. [74.96.105.49]) by mx.google.com with ESMTPSA id z8sm18106968qaw.17.2014.04.04.12.58.45 for (version=TLSv1.2 cipher=AES128-GCM-SHA256 bits=128/128); Fri, 04 Apr 2014 12:58:45 -0700 (PDT) From: Alex Deucher To: dri-devel@lists.freedesktop.org, jani.nikula@linux.intel.com, ville.syrjala@linux.intel.com, treding@nvidia.com Subject: [PATCH 3/4] drm/dp/i2c: Update comments about common i2c over dp assumptions Date: Fri, 4 Apr 2014 15:58:38 -0400 Message-Id: <1396641519-18529-4-git-send-email-alexander.deucher@amd.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1396641519-18529-1-git-send-email-alexander.deucher@amd.com> References: <1396641519-18529-1-git-send-email-alexander.deucher@amd.com> MIME-Version: 1.0 Cc: Alex Deucher , Jani Nikula X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Spam-Status: No, score=-4.7 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If you are using the common dp over i2c functionality, it is asumed that the aux transfer function does not modify the any of the msg structure other than the reply field. Doing so breaks the logic in the common code. Signed-off-by: Alex Deucher Cc: Ville Syrjälä Cc: Jani Nikula Cc: Thierry Reding Reviewed-by: Ville Syrjälä --- drivers/gpu/drm/drm_dp_helper.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index dfe4cf4..948de4f 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -577,7 +577,9 @@ static u32 drm_dp_i2c_functionality(struct i2c_adapter *adapter) /* * Transfer a single I2C-over-AUX message and handle various error conditions, - * retrying the transaction as appropriate. + * retrying the transaction as appropriate. It is assumed that the + * aux->transfer function does not modify anything in the msg other than the + * reply field. */ static int drm_dp_i2c_do_msg(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) {