From patchwork Tue Sep 12 16:56:18 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 9949665 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 D287B60360 for ; Tue, 12 Sep 2017 16:57:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A6947209CD for ; Tue, 12 Sep 2017 16:57:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9AAEA27F8E; Tue, 12 Sep 2017 16:57:17 +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=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED 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 EAD5828068 for ; Tue, 12 Sep 2017 16:57:16 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 239F26E6C2; Tue, 12 Sep 2017 16:57:16 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) by gabe.freedesktop.org (Postfix) with ESMTPS id 521F48995F for ; Tue, 12 Sep 2017 16:57:14 +0000 (UTC) Received: from localhost (unknown [12.145.98.253]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id D4F6C9EE; Tue, 12 Sep 2017 16:57:13 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Subject: [PATCH 4.4 23/31] drm/bridge: adv7511: Use work_struct to defer hotplug handing to out of irq context Date: Tue, 12 Sep 2017 09:56:18 -0700 Message-Id: <20170912165248.541459149@linuxfoundation.org> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20170912165247.436880944@linuxfoundation.org> References: <20170912165247.436880944@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Cc: Nhan Nguyen , Greg Kroah-Hartman , dri-devel@lists.freedesktop.org, stable@vger.kernel.org, Wolfram Sang , Laurent Pinchart , Thong Ho 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: John Stultz commit 518cb7057a59b9441336d2e88a396d52b6ab0cce upstream. 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 Tested-by: Laurent Pinchart Signed-off-by: John Stultz Signed-off-by: Archit Taneja Link: http://patchwork.freedesktop.org/patch/msgid/1484614372-15342-2-git-send-email-john.stultz@linaro.org Signed-off-by: Thong Ho Signed-off-by: Nhan Nguyen Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i2c/adv7511.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/i2c/adv7511.c +++ b/drivers/gpu/drm/i2c/adv7511.c @@ -36,7 +36,10 @@ struct adv7511 { bool edid_read; wait_queue_head_t wq; + struct work_struct hpd_work; + struct drm_encoder *encoder; + struct drm_connector connector; bool embedded_sync; enum adv7511_sync_polarity vsync_polarity; @@ -429,6 +432,13 @@ static bool adv7511_hpd(struct 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; @@ -446,7 +456,7 @@ static int adv7511_irq_process(struct ad regmap_write(adv7511->regmap, ADV7511_REG_INT(1), irq1); if (process_hpd && irq0 & ADV7511_INT0_HDP && adv7511->encoder) - drm_helper_hpd_irq_event(adv7511->encoder->dev); + schedule_work(&adv7511->hpd_work); if (irq0 & ADV7511_INT0_EDID_READY || irq1 & ADV7511_INT1_DDC_ERROR) { adv7511->edid_read = true; @@ -922,6 +932,8 @@ static int adv7511_probe(struct i2c_clie if (!adv7511->i2c_edid) return -ENOMEM; + INIT_WORK(&adv7511->hpd_work, adv7511_hpd_work); + if (i2c->irq) { init_waitqueue_head(&adv7511->wq);