From patchwork Mon Dec 12 21:00:37 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Stultz X-Patchwork-Id: 9471365 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id CA32460573 for ; Mon, 12 Dec 2016 21:01:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BF3B2284CA for ; Mon, 12 Dec 2016 21:01:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B418B2851D; Mon, 12 Dec 2016 21:01:17 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 3C7C5284CA for ; Mon, 12 Dec 2016 21:01:17 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C69D66E415; Mon, 12 Dec 2016 21:01:14 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-pg0-x22b.google.com (mail-pg0-x22b.google.com [IPv6:2607:f8b0:400e:c05::22b]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1BAC76E35D for ; Mon, 12 Dec 2016 21:00:47 +0000 (UTC) Received: by mail-pg0-x22b.google.com with SMTP id p66so39082389pga.2 for ; Mon, 12 Dec 2016 13:00:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=pnGcfhMmpWOXvYo10vJgDqvVFYt7wrezhVHUdsCMebA=; b=eeJK1mZ7QNleLlpN0xmsg1k8sNohO/gPLaSWmfJ5s5eZj90TcNOofyiN2g8rux+8lU zevamSOKNDGFXIIoNZjBoTBIMBPsN9thIhI8OvOQFBYSczH9yzZ/SSVmbmRIN0N8CrMN AdsXcYEyn/qydAKGnE0nWBI1JyTQ1W3+gFqKY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=pnGcfhMmpWOXvYo10vJgDqvVFYt7wrezhVHUdsCMebA=; b=hpjDlPPYc0AYBYCRYvY9IMUziutlXFDavIJFzq+cOMABn7LlvheKOLQOxQWfq9hFqm 5ms2Ji6e4YbqaBKywb0RLLz4XWr0IWReaIhBwcCBCz+8m5+XAnzzGuiUB20ZSWg8sQcV 5MC94LgVi/GMkes7lxfl0SIGQSW/dIiwqCAsuouMVW3yJSwE6073tg1i7dGqMkj7qFRm Gb24Wy2u5v/r0tSrtNsQa7AJfRDnrT1yb4gDyfXw31tRRv8/KbQ207KLfV5AUfgdqQEI WgQC8O8nc7EXqheiRMNn7oS5arTWqjeZguYyg+oz/JMVF/rge6qePQYTI4po06+ERAM/ 1edg== X-Gm-Message-State: AKaTC03JDogMjB3RBjfFRgXEUvDbRd7w/jIFESqqLMLYIYmKbGWa4yKV9qkqo5/eAxvjjy5j X-Received: by 10.99.251.69 with SMTP id w5mr33468670pgj.124.1481576446476; Mon, 12 Dec 2016 13:00:46 -0800 (PST) Received: from localhost.localdomain ([2601:1c2:1002:83f0:4e72:b9ff:fe99:466a]) by smtp.gmail.com with ESMTPSA id f3sm41074078pga.45.2016.12.12.13.00.45 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 12 Dec 2016 13:00:45 -0800 (PST) From: John Stultz To: lkml Subject: [RFC][PATCH 1/5 v3] drm/bridge: adv7511: Use work_struct to defer hotplug handing to out of irq context Date: Mon, 12 Dec 2016 13:00:37 -0800 Message-Id: <1481576441-23529-2-git-send-email-john.stultz@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1481576441-23529-1-git-send-email-john.stultz@linaro.org> References: <1481576441-23529-1-git-send-email-john.stultz@linaro.org> Cc: dri-devel@lists.freedesktop.org, Wolfram Sang , Laurent Pinchart X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP I was recently seeing issues with EDID probing, where the logic to wait for the EDID read bit to be set by the IRQ wasn't happening and the code would time out and fail. Digging deeper, I found this was due to the fact that IRQs were disabled as we were running in IRQ context from the HPD signal. Thus this patch changes the logic to handle the HPD signal via a work_struct so we can be out of irq context. With this patch, the EDID probing on hotplug does not time out. Cc: David Airlie Cc: Archit Taneja Cc: Wolfram Sang Cc: Lars-Peter Clausen Cc: Laurent Pinchart Cc: dri-devel@lists.freedesktop.org Reviewed-by: Laurent Pinchart Signed-off-by: John Stultz --- v3: Rename irq_work to hpd_work and remove extra whitespace, as suggested by Laurent --- drivers/gpu/drm/bridge/adv7511/adv7511.h | 2 ++ drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 11 ++++++++++- 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511.h b/drivers/gpu/drm/bridge/adv7511/adv7511.h index 992d76c..0396791 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511.h +++ b/drivers/gpu/drm/bridge/adv7511/adv7511.h @@ -317,6 +317,8 @@ struct adv7511 { bool edid_read; wait_queue_head_t wq; + struct work_struct hpd_work; + struct drm_bridge bridge; struct drm_connector connector; diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c index 8dba729..4fcea44 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c @@ -402,6 +402,13 @@ static bool adv7511_hpd(struct adv7511 *adv7511) return false; } +static void adv7511_hpd_work(struct work_struct *work) +{ + struct adv7511 *adv7511 = container_of(work, struct adv7511, hpd_work); + + drm_helper_hpd_irq_event(adv7511->connector.dev); +} + static int adv7511_irq_process(struct adv7511 *adv7511, bool process_hpd) { unsigned int irq0, irq1; @@ -419,7 +426,7 @@ static int adv7511_irq_process(struct adv7511 *adv7511, bool process_hpd) regmap_write(adv7511->regmap, ADV7511_REG_INT(1), irq1); if (process_hpd && irq0 & ADV7511_INT0_HPD && adv7511->bridge.encoder) - drm_helper_hpd_irq_event(adv7511->connector.dev); + schedule_work(&adv7511->hpd_work); if (irq0 & ADV7511_INT0_EDID_READY || irq1 & ADV7511_INT1_DDC_ERROR) { adv7511->edid_read = true; @@ -1006,6 +1013,8 @@ static int adv7511_probe(struct i2c_client *i2c, const struct i2c_device_id *id) goto err_i2c_unregister_edid; } + INIT_WORK(&adv7511->hpd_work, adv7511_hpd_work); + if (i2c->irq) { init_waitqueue_head(&adv7511->wq);