From patchwork Wed Apr 21 23:37:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kuogee Hsieh X-Patchwork-Id: 12217171 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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 26A25C433B4 for ; Wed, 21 Apr 2021 23:38:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 038F861428 for ; Wed, 21 Apr 2021 23:38:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234916AbhDUXjN (ORCPT ); Wed, 21 Apr 2021 19:39:13 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:25277 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343732AbhDUXjK (ORCPT ); Wed, 21 Apr 2021 19:39:10 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1619048316; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=8BP+eMH3HNp0YASI+KjmXU1rq+O86jtgvX5SsgJB5bE=; b=YS3fecGrDD4BMODohKVLuUuLrzxzUo2mUrt9BxODA/n4U3LKg5sC4R5EzILNzO3Um6oqVcd1 haBJsLdop8W5+PM4fntSbUz3QNcg5YGQC1qhB97F5B48p5MRBE8lFKL50/i59DtqmYcbcEiW MYBRuabpW+V2cEeCl4OnmVArZdM= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n01.prod.us-west-2.postgun.com with SMTP id 6080b75ff34440a9d4c308c2 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 21 Apr 2021 23:38:07 GMT Sender: khsieh=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id BCDBAC43146; Wed, 21 Apr 2021 23:38:07 +0000 (UTC) Received: from khsieh-linux1.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: khsieh) by smtp.codeaurora.org (Postfix) with ESMTPSA id 78946C4338A; Wed, 21 Apr 2021 23:38:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 78946C4338A Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=khsieh@codeaurora.org From: Kuogee Hsieh To: robdclark@gmail.com, sean@poorly.run, swboyd@chromium.org Cc: Kuogee Hsieh , abhinavk@codeaurora.org, aravindh@codeaurora.org, airlied@linux.ie, daniel@ffwll.ch, linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 3/4] drm/msm/dp: check main link status before start aux read Date: Wed, 21 Apr 2021 16:37:37 -0700 Message-Id: <1619048258-8717-4-git-send-email-khsieh@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1619048258-8717-1-git-send-email-khsieh@codeaurora.org> References: <1619048258-8717-1-git-send-email-khsieh@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Maybe when the cable is disconnected the DP phy should be shutdown and some bit in the phy could effectively "cut off" the aux channel and then NAKs would start coming through here in the DP controller I/O register space. This patch have DP aux channel read/write to return NAK immediately if DP controller connection status is in unplugged state. Changes in V4: -- split this patch as stand alone patch Signed-off-by: Kuogee Hsieh --- drivers/gpu/drm/msm/dp/dp_aux.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/msm/dp/dp_aux.c b/drivers/gpu/drm/msm/dp/dp_aux.c index 7c22bfe..fae3806 100644 --- a/drivers/gpu/drm/msm/dp/dp_aux.c +++ b/drivers/gpu/drm/msm/dp/dp_aux.c @@ -343,6 +343,11 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux, mutex_lock(&aux->mutex); + if (!dp_catalog_link_is_connected(aux->catalog)) { + ret = -ETIMEDOUT; + goto unlock_exit; + } + aux->native = msg->request & (DP_AUX_NATIVE_WRITE & DP_AUX_NATIVE_READ); /* Ignore address only message */