From nobody Tue Apr 7 08:10:18 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 133FDC4332F for ; Wed, 12 Oct 2022 16:29:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230072AbiJLQ3q (ORCPT ); Wed, 12 Oct 2022 12:29:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41482 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230094AbiJLQ3b (ORCPT ); Wed, 12 Oct 2022 12:29:31 -0400 Received: from mail-pg1-x52f.google.com (mail-pg1-x52f.google.com [IPv6:2607:f8b0:4864:20::52f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8F1EFFC1E2 for ; Wed, 12 Oct 2022 09:29:18 -0700 (PDT) Received: by mail-pg1-x52f.google.com with SMTP id f193so16016846pgc.0 for ; Wed, 12 Oct 2022 09:29:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=2YtuM603E+k6aqfoZ0FWElqsR6+Ku8jsdYOTJIWy3xg=; b=JJVRnC0QblF7NOzu5SIQUJXUdGu4jFeHBztSiP6B0Hk5imlX8l5zmBJWT76HdJEPEV TRkk4ztAQ7AiB3Uv5CWTnWVhliNgd/e3mdY0OuykXX5b6Y0gwK5gBC2zNHtt1cQ/NigM aHA7wABZ2CzyXwzkx/l2K6TCJjq1djZWp7XGU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=2YtuM603E+k6aqfoZ0FWElqsR6+Ku8jsdYOTJIWy3xg=; b=HKAXFTFCHc0l8Sp53T8/aYVLjsPvUXUiH3Cuqn1HHVA73rraDw+po8ErbHEeQLZYrA 0iTb8EypI0BYZdTO1VdGdbUkB21pbk1Z40ZQgvfh/ak9klXhs2rvvjaUO4ZzIkjZWhrX RSKhFmvrXj2CT3dEB1iUc44hgQOc3DLN8+LL/Frm+e3AaEW2fyulJkQhjLreh98Q8HDk uLj44eRDLS4vKx/2UBXXw3FKiGil5dcNUOmbAmeZ07o3xW7BmLyFy/YSqy6MmbIvt3FI OHMvbllywoZ7F3ECQb74v1XYYR/oFD7AQARQkKHiQ9NzO0wWfixTpEAVZq0JMqwXnMyC HOhw== X-Gm-Message-State: ACrzQf1G0WL/EMxJdiVscE6tcJYtlDna+dCiO4/l5emwgLpkh+mtPi4Z ESfweYbdCgbEK/TC8D6n0kXo5w== X-Google-Smtp-Source: AMsMyM72DawyO7B4FUZI7F8l22On/SCorvViNiLwZ6BHyI4yq5QUrHG1RLmH8urxD793dTuMqmVQ1Q== X-Received: by 2002:a63:b12:0:b0:44a:d193:6b16 with SMTP id 18-20020a630b12000000b0044ad1936b16mr26631125pgl.604.1665592157605; Wed, 12 Oct 2022 09:29:17 -0700 (PDT) Received: from treapking.tpe.corp.google.com ([2401:fa00:1:10:2921:f6a9:5848:18e1]) by smtp.gmail.com with ESMTPSA id l4-20020a635704000000b0045dc85c4a5fsm9722163pgb.44.2022.10.12.09.29.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Oct 2022 09:29:17 -0700 (PDT) From: Pin-yen Lin To: Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , David Airlie , Daniel Vetter Cc: Pin-yen Lin , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/3] drm/bridge: it6505: Improve synchronization between extcon subsystem Date: Thu, 13 Oct 2022 00:28:59 +0800 Message-Id: <20221012162900.2876686-4-treapking@chromium.org> X-Mailer: git-send-email 2.38.0.rc1.362.ged0d419d3c-goog In-Reply-To: <20221012162900.2876686-1-treapking@chromium.org> References: <20221012162900.2876686-1-treapking@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Originally, the it6505 relies on a short sleep in the IRQ handler and a long sleep to make sure it6505->lane_swap and it6505->lane_count is configured in it6505_extcon_work and it6505_detect, respectively. Use completion and additional DPCD read to remove the unnecessary waits, and use a different lock for it6505_extcon_work and the threaded IRQ handler because they no longer need to run exclusively. The wait time of the completion is usually less than 10ms in local experiments, but leave it larger here just in case. Signed-off-by: Pin-yen Lin --- drivers/gpu/drm/bridge/ite-it6505.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/i= te-it6505.c index cf94e44ec73a..52515b43171c 100644 --- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -412,6 +412,7 @@ struct it6505 { * Mutex protects extcon and interrupt functions from interfering * each other. */ + struct mutex irq_lock; struct mutex extcon_lock; struct mutex mode_lock; /* used to bridge_detect */ struct mutex aux_lock; /* used to aux data transfers */ @@ -440,7 +441,7 @@ struct it6505 { enum hdcp_state hdcp_status; struct delayed_work hdcp_work; struct work_struct hdcp_wait_ksv_list; - struct completion wait_edid_complete; + struct completion extcon_completion; u8 auto_train_retry; bool hdcp_desired; bool is_repeater; @@ -2315,8 +2316,8 @@ static void it6505_irq_hpd(struct it6505 *it6505) it6505->hpd_state ? "high" : "low"); =20 if (it6505->hpd_state) { - wait_for_completion_timeout(&it6505->wait_edid_complete, - msecs_to_jiffies(6000)); + wait_for_completion_timeout(&it6505->extcon_completion, + msecs_to_jiffies(1000)); it6505_aux_on(it6505); if (it6505->dpcd[0] =3D=3D 0) { it6505_get_dpcd(it6505, DP_DPCD_REV, it6505->dpcd, @@ -2328,7 +2329,6 @@ static void it6505_irq_hpd(struct it6505 *it6505) =20 DRM_DEV_DEBUG_DRIVER(dev, "it6505->sink_count: %d", it6505->sink_count); - it6505_lane_termination_on(it6505); it6505_lane_power_on(it6505); =20 @@ -2487,8 +2487,7 @@ static irqreturn_t it6505_int_threaded_handler(int un= used, void *data) }; int int_status[3], i; =20 - msleep(100); - mutex_lock(&it6505->extcon_lock); + mutex_lock(&it6505->irq_lock); =20 if (it6505->enable_drv_hold || !it6505->powered) goto unlock; @@ -2518,7 +2517,7 @@ static irqreturn_t it6505_int_threaded_handler(int un= used, void *data) } =20 unlock: - mutex_unlock(&it6505->extcon_lock); + mutex_unlock(&it6505->irq_lock); =20 return IRQ_HANDLED; } @@ -2695,9 +2694,12 @@ static void it6505_extcon_work(struct work_struct *w= ork) */ if (ret) it6505_poweron(it6505); + + complete_all(&it6505->extcon_completion); } else { DRM_DEV_DEBUG_DRIVER(dev, "start to power off"); pm_runtime_put_sync(dev); + reinit_completion(&it6505->extcon_completion); =20 drm_helper_hpd_irq_event(it6505->bridge.dev); memset(it6505->dpcd, 0, sizeof(it6505->dpcd)); @@ -3268,6 +3270,7 @@ static int it6505_i2c_probe(struct i2c_client *client, if (!it6505) return -ENOMEM; =20 + mutex_init(&it6505->irq_lock); mutex_init(&it6505->extcon_lock); mutex_init(&it6505->mode_lock); mutex_init(&it6505->aux_lock); @@ -3323,7 +3326,7 @@ static int it6505_i2c_probe(struct i2c_client *client, INIT_WORK(&it6505->link_works, it6505_link_training_work); INIT_WORK(&it6505->hdcp_wait_ksv_list, it6505_hdcp_wait_ksv_list); INIT_DELAYED_WORK(&it6505->hdcp_work, it6505_hdcp_work); - init_completion(&it6505->wait_edid_complete); + init_completion(&it6505->extcon_completion); memset(it6505->dpcd, 0, sizeof(it6505->dpcd)); it6505->powered =3D false; it6505->enable_drv_hold =3D DEFAULT_DRV_HOLD; --=20 2.38.0.rc1.362.ged0d419d3c-goog