From patchwork Tue Jan 3 19:41:38 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Stultz X-Patchwork-Id: 89721 Delivered-To: patches@linaro.org Received: by 10.140.20.101 with SMTP id 92csp8166374qgi; Tue, 3 Jan 2017 11:41:51 -0800 (PST) X-Received: by 10.84.232.135 with SMTP id i7mr105270672plk.12.1483472511725; Tue, 03 Jan 2017 11:41:51 -0800 (PST) Return-Path: Received: from mail-pg0-x233.google.com (mail-pg0-x233.google.com. [2607:f8b0:400e:c05::233]) by mx.google.com with ESMTPS id s11si69886494pgc.259.2017.01.03.11.41.51 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 03 Jan 2017 11:41:51 -0800 (PST) Received-SPF: pass (google.com: domain of john.stultz@linaro.org designates 2607:f8b0:400e:c05::233 as permitted sender) client-ip=2607:f8b0:400e:c05::233; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org; spf=pass (google.com: domain of john.stultz@linaro.org designates 2607:f8b0:400e:c05::233 as permitted sender) smtp.mailfrom=john.stultz@linaro.org; dmarc=pass (p=NONE dis=NONE) header.from=linaro.org Received: by mail-pg0-x233.google.com with SMTP id g1so178781057pgn.0 for ; Tue, 03 Jan 2017 11:41:51 -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=WFlauWJNusZDpjIq7m5koeo7DbVEiEDdOE/51ddjuBE=; b=Cj4PbOFXbYPpj1VI8of/PEmQDeTJ6YWOy5umZtwETVjDaWdte5/rdOeR0SXQdMnE4v VEN3Cid0rPXF+vIoOOAiM6azDiIMEsEv7mRcIFN62sjYbllH1sMNLTCGc1ZsfiOW/HW5 5KhxSENF9tIbEBhZ9PGu42vkczVdgEES4KyUA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=WFlauWJNusZDpjIq7m5koeo7DbVEiEDdOE/51ddjuBE=; b=o4UftJHXdEHeM3xuUBeIFTjDHV9blLoSM0De2IrPvA30aYrjD7niEzc3tQxONP5fZB XzwY81WaBQwKHCCwjkaWlIsVDiONYzxhqXg5Qpe3epqxdd36KRHxsXe3p/X+eLseYt6z v0D3G3Axqt1rJeGz0HGmcinODYbb1JeMNgPOpX3TRB4TRaeUjPuOzApSkSNHr8075Iyt XjI8PBzMz8G9oL8pwQc2J628zc0RchYT5e88rPJzADqz6z6xRn1b+SEuVyJLDnLL0YzD 2LmlkTpg487Woq8/nS8rTUPaMWbamQ3EDNZJbg81Ixjled8VJdRvxEP6FK31Kk4goZNe VxKg== X-Gm-Message-State: AIkVDXJWNytdQMQbWwIDxehnjXMWs7+gCkbWlKtg+l+iQQzEO34lVTN6aN4txXNP33HKRpOXZxc= X-Received: by 10.98.138.72 with SMTP id y69mr59805712pfd.52.1483472511422; Tue, 03 Jan 2017 11:41:51 -0800 (PST) Return-Path: Received: from localhost.localdomain ([2601:1c2:1002:83f0:4e72:b9ff:fe99:466a]) by smtp.gmail.com with ESMTPSA id y62sm77865957pfk.52.2017.01.03.11.41.50 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 03 Jan 2017 11:41:50 -0800 (PST) From: John Stultz To: lkml Cc: John Stultz , David Airlie , Archit Taneja , Wolfram Sang , Lars-Peter Clausen , Laurent Pinchart , dri-devel@lists.freedesktop.org Subject: [PATCH 1/5 v3] drm/bridge: adv7511: Use work_struct to defer hotplug handing to out of irq context Date: Tue, 3 Jan 2017 11:41:38 -0800 Message-Id: <1483472502-16403-2-git-send-email-john.stultz@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1483472502-16403-1-git-send-email-john.stultz@linaro.org> References: <1483472502-16403-1-git-send-email-john.stultz@linaro.org> 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(-) -- 2.7.4 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);