From patchwork Tue Nov 29 05:04:40 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Stultz X-Patchwork-Id: 9450941 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 697196074E for ; Tue, 29 Nov 2016 05:05:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5D2F827D64 for ; Tue, 29 Nov 2016 05:05:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4DCCA27F89; Tue, 29 Nov 2016 05:05:06 +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 E55DB27D64 for ; Tue, 29 Nov 2016 05:05:00 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 06F2B6E3C0; Tue, 29 Nov 2016 05:04:55 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-pg0-x236.google.com (mail-pg0-x236.google.com [IPv6:2607:f8b0:400e:c05::236]) by gabe.freedesktop.org (Postfix) with ESMTPS id 52C6F6E359 for ; Tue, 29 Nov 2016 05:04:53 +0000 (UTC) Received: by mail-pg0-x236.google.com with SMTP id 3so65153189pgd.0 for ; Mon, 28 Nov 2016 21:04:53 -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=j6S/3acIyxRQeYjc51RBt6E42wGAXFnhjEmUtr6FoVU=; b=JHciRd0Lvc22DyTqW+ZVQ0B3g8byRnFcwlngk31yCnYNl9qgzwZKDw2wVXLfL9yOL8 aN43ArGrYa/EqpOUYVrqICzaRB5ALJIrYXUEcoIf9UWt6fay2Z/PeDDifUVko1eavI7O nDLTqPQ9sHRUaK/soSgKiOtxr14tGmwKIGeFY= 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=j6S/3acIyxRQeYjc51RBt6E42wGAXFnhjEmUtr6FoVU=; b=BSbwWf/murF8DhZES8FKu8rKsQMDtnCHy0ZxLE6618NkVsOSetB5rIoIB/PzxW5v7S Qn/9wuwxEL89x8EfHXZIZRrnWAxbrZJ1/yOGGQ5UtHcYRjnEqorQ5+kU1mF2HOy2Qv9u 6sldc+27ykYNzEpSS6x8LvQ4H3bXX44ce6Wl7UY7kJZYE6cEkGuf0IBYw1KpQQzDkOys mGfyzOMG038qM1S+PqAIA+jkpT5m+EX70L8MWOAe9yKVkMyfLiSHyk0AEl2yW1+lfFX4 Rn2igxK3FKhgL+mPdDZS802+AZVVGh8MFfYL8Bi0KPjbTuI7TfWgPrVWwSevyha53mRC azug== X-Gm-Message-State: AKaTC01gz1Mh7ZXA/oVIK/86M+/PlqUA4R1+D9EpuBBG4O6GpqQBG1MK+ijcS9S7HXiTLb0w X-Received: by 10.98.103.84 with SMTP id b81mr25719417pfc.6.1480395892806; Mon, 28 Nov 2016 21:04:52 -0800 (PST) Received: from localhost.localdomain ([2601:1c2:1002:83f0:4e72:b9ff:fe99:466a]) by smtp.gmail.com with ESMTPSA id b29sm73191498pgn.48.2016.11.28.21.04.51 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 28 Nov 2016 21:04:52 -0800 (PST) From: John Stultz To: lkml Subject: [RFC][PATCH 1/5 v2] drm/bridge: adv7511: Use work_struct to defer hotplug handing to out of irq context Date: Mon, 28 Nov 2016 21:04:40 -0800 Message-Id: <1480395884-5471-2-git-send-email-john.stultz@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1480395884-5471-1-git-send-email-john.stultz@linaro.org> References: <1480395884-5471-1-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 Signed-off-by: John Stultz Reviewed-by: Laurent Pinchart --- v2: Reworked to properly fix the issue rather then just delaying for 200ms drivers/gpu/drm/bridge/adv7511/adv7511.h | 2 ++ drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 12 +++++++++++- 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511.h b/drivers/gpu/drm/bridge/adv7511/adv7511.h index 992d76c..2a1e722 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 irq_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..b38e743 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c @@ -402,6 +402,14 @@ static bool adv7511_hpd(struct adv7511 *adv7511) return false; } +static void adv7511_irq_work(struct work_struct *work) +{ + struct adv7511 *adv7511 = container_of(work, struct adv7511, irq_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 +427,7 @@ 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->irq_work); if (irq0 & ADV7511_INT0_EDID_READY || irq1 & ADV7511_INT1_DDC_ERROR) { adv7511->edid_read = true; @@ -1006,6 +1014,8 @@ static int adv7511_probe(struct i2c_client *i2c, const struct i2c_device_id *id) goto err_i2c_unregister_edid; } + INIT_WORK(&adv7511->irq_work, adv7511_irq_work); + if (i2c->irq) { init_waitqueue_head(&adv7511->wq);