From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-03.galae.net (smtpout-03.galae.net [185.246.85.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 471BD49B45D for ; Mon, 12 Oct 2026 15:12:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.246.85.4 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791817940; cv=none; b=Z/MW+D5hZilPBHtqpZ1f9NRyNZl/d/oNZ3jpHzmv5C/rog3v5+/5DUc/q2wiCCvUOOde05voOJQQKuhnzfbmrkrHgd+5Tp1+YHo2FTSuqPrjbk66yttBm5yaL7MsUjmWjQQxxPckc5QhUY4//EradmBkQj7R5KrTUJWu/nexZ58= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791817940; c=relaxed/simple; bh=B6NHRXPrUrRowHMKwGnNjBxaLCD9lUFYYYPqcfEwvHI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=nkRphAOBVHTkTkWsjp7PmIJbWxbdSlZr8dhdSyptdYeqYtEdi+rLKUpc3jeMsYpXHtCHgcpRQssqr+vskgBk33udBiToxrEYH1JKbFiGBiyUb6hmzo6Wz3oyCodvSFmlXWpwYwl+29+8Z2n8DExlQYjsKO1h9LuJxyLqIjNpTzQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=QEw4ceLz; arc=none smtp.client-ip=185.246.85.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="QEw4ceLz" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-03.galae.net (Postfix) with ESMTPS id 9F6634E411F7; Mon, 12 Oct 2026 15:12:17 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 71B30601A6; Mon, 12 Oct 2026 15:12:17 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id AFF8411D70CD6; Mon, 12 Oct 2026 17:12:11 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1791817935; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=P/Q4nFBYsii5RLmePNAPJ+fdVFCY7TJHBVJr5R7oOUU=; b=QEw4ceLzWeB8qinUu3mC0wNsLS4KwoVzdMeNR1LuDZOqpeG4PwWut/oihiBkHGQnbMZxhl OZp32Dlsdo/K2c61sEs2QPrVvPALXX8V2EcPeErhamuicCpfdVR20vOzkjxnlgKCaJU0Yr exCKtpfmW3UbWGlASwH576cy09yT7rUudgRtXAeGCZNYkyHiGgHQwOTi9/PvsrPO8E6Lls N2qpi/NxPYL9Cm/9PeF0JNTF7bdFq7AaEr90/6sAOncIfSe0wPcROPU/Prd7nCb56dQ7c9 rdyz+0CVJcpxqT964ronT75nEzdCaq9aXxGrcGzf01uBswPl3tFKxLGSMOIsqA== From: Kory Maincent Date: Mon, 12 Oct 2026 17:11:03 +0200 Subject: [PATCH RFC v3 8/8] drm/mediatek: Use dp_connector helpers to expose link training state Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261012-feat_link_cap-v3-8-7517f4aba0f3@bootlin.com> References: <20261012-feat_link_cap-v3-0-7517f4aba0f3@bootlin.com> In-Reply-To: <20261012-feat_link_cap-v3-0-7517f4aba0f3@bootlin.com> To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Rodrigo Vivi , Joonas Lahtinen , Tvrtko Ursulin , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Luca Ceresoli , Chun-Kuang Hu , Philipp Zabel , Matthias Brugger , AngeloGioacchino Del Regno , Dmitry Baryshkov , Daniel Stone Cc: Thomas Petazzoni , Mark Yacoub , Sean Paul , Manasi Navare , Drew Davenport , Louis Chauvet , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Kory Maincent X-Mailer: b4 0.16.1-dev-17221 X-Last-TLS-Session-Version: TLSv1.3 Adopt the DRM core DisplayPort helpers by setting DRM_BRIDGE_OP_DP and populating the bridge dp_link_caps at probe time. Report the sink capabilities on hotplug, reset them on disconnect, and report the link parameters once link training succeeds. Signed-off-by: Kory Maincent --- Not tested. I believed I had a board with this device, but it actually uses an anx7625 bridge. I'm unable to test it; it would be appreciated if someone else could, so the change isn't dropped. Changes in v3: - Sync and report sink capabilities from the HPD thread for DisplayPort, or in atomic_enable for eDP. Reset them on unplug, or atomic disable and only report link parameters after successful training. - Add connection_mutex lock for DisplayPort in the IRQ thread. Changes in v2: - Remove voltage swing and pre emphasis properties. --- drivers/gpu/drm/mediatek/mtk_dp.c | 79 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 75 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c index f656b85b84212..2e2596eaa342e 100644 --- a/drivers/gpu/drm/mediatek/mtk_dp.c +++ b/drivers/gpu/drm/mediatek/mtk_dp.c @@ -1812,6 +1812,35 @@ static void mtk_dp_train_change_mode(struct mtk_dp *mtk_dp) mtk_dp_reset_swing_pre_emphasis(mtk_dp); } +static void _mtk_dp_report_link_train(struct mtk_dp *mtk_dp) +{ + u32 rate, nlanes; + bool dsc = false; + + rate = drm_dp_bw_code_to_link_rate(mtk_dp->train_info.link_rate); + nlanes = mtk_dp->train_info.lane_count; + + drm_dp_set_cur_link_params(mtk_dp->conn, rate, nlanes, dsc); +} + +static void mtk_dp_report_link_train(struct mtk_dp *mtk_dp) +{ + struct drm_modeset_lock *lock; + int ret; + + if (!mtk_dp->conn) + return; + + lock = &mtk_dp->conn->dev->mode_config.connection_mutex; + ret = drm_modeset_lock_single_interruptible(lock); + if (ret) + return; + + _mtk_dp_report_link_train(mtk_dp); + + drm_modeset_unlock(lock); +} + static int mtk_dp_training(struct mtk_dp *mtk_dp) { int ret; @@ -2015,6 +2044,8 @@ static irqreturn_t mtk_dp_hpd_event_thread(int hpd, void *dev) ret = mtk_dp_training(mtk_dp); if (ret) drm_err(mtk_dp->drm_dev, "Training failed, %d\n", ret); + else + mtk_dp_report_link_train(mtk_dp); mtk_dp->enabled = true; } @@ -2145,9 +2176,12 @@ mtk_dp_bdg_detect(struct drm_bridge *bridge, struct drm_connector *connector) struct mtk_dp *mtk_dp = mtk_dp_from_bridge(bridge); enum drm_connector_status ret = connector_status_disconnected; bool enabled = mtk_dp->enabled; + int err; - if (!mtk_dp->train_info.cable_plugged_in) + if (!mtk_dp->train_info.cable_plugged_in) { + drm_dp_sink_reset_caps(connector); return ret; + } if (!enabled) mtk_dp_aux_panel_poweron(mtk_dp, true); @@ -2160,9 +2194,18 @@ mtk_dp_bdg_detect(struct drm_bridge *bridge, struct drm_connector *connector) * whether we connect to a sink device. */ - if (drm_dp_read_sink_count(&mtk_dp->aux) > 0) + if (drm_dp_read_sink_count(&mtk_dp->aux) > 0) { ret = connector_status_connected; + err = drm_dp_sink_sync_caps(connector, &mtk_dp->aux, NULL); + if (err) + drm_dbg_kms(mtk_dp->aux.drm_dev, + "%s: error sink caps synchronisation (%d)\n", + mtk_dp->aux.name, err); + } else { + drm_dp_sink_reset_caps(connector); + } + if (!enabled) mtk_dp_aux_panel_poweron(mtk_dp, false); @@ -2390,12 +2433,20 @@ static void mtk_dp_bridge_atomic_enable(struct drm_bridge *bridge, if (mtk_dp->data->bridge_type == DRM_MODE_CONNECTOR_eDP) { mtk_dp_aux_panel_poweron(mtk_dp, true); + ret = drm_dp_sink_sync_caps(mtk_dp->conn, &mtk_dp->aux, NULL); + if (ret) + drm_dbg_kms(mtk_dp->aux.drm_dev, + "%s: error sink caps synchronisation (%d)\n", + mtk_dp->aux.name, ret); + /* Training */ ret = mtk_dp_training(mtk_dp); if (ret) { drm_err(mtk_dp->drm_dev, "Training failed, %d\n", ret); goto power_off_aux; } + + _mtk_dp_report_link_train(mtk_dp); } ret = mtk_dp_video_config(mtk_dp); @@ -2435,6 +2486,7 @@ static void mtk_dp_bridge_atomic_disable(struct drm_bridge *bridge, if (mtk_dp->data->bridge_type == DRM_MODE_CONNECTOR_eDP) { mtk_dp->enabled = false; mtk_dp_aux_panel_poweron(mtk_dp, false); + drm_dp_sink_reset_caps(mtk_dp->conn); } mtk_dp_update_plugged_status(mtk_dp); @@ -2740,11 +2792,14 @@ static int mtk_dp_edp_link_panel(struct drm_dp_aux *mtk_aux) return 0; } +static int mtk_dp_rates[] = {162000, 270000, 540000, 810000}; + static int mtk_dp_probe(struct platform_device *pdev) { + struct drm_connector_dp_link_caps *source_caps; struct mtk_dp *mtk_dp; struct device *dev = &pdev->dev; - int ret; + int ret, i, max_rate; mtk_dp = devm_drm_bridge_alloc(dev, struct mtk_dp, bridge, &mtk_dp_bridge_funcs); @@ -2758,6 +2813,20 @@ static int mtk_dp_probe(struct platform_device *pdev) if (ret) return dev_err_probe(dev, ret, "Failed to parse dt\n"); + source_caps = devm_kzalloc(dev, sizeof(*source_caps), GFP_KERNEL); + if (!source_caps) + return -ENOMEM; + + source_caps->nlanes = mtk_dp->max_lanes; + source_caps->link_rates = mtk_dp_rates; + + max_rate = drm_dp_bw_code_to_link_rate(mtk_dp->max_linkrate); + for (i = 0; i < ARRAY_SIZE(mtk_dp_rates); i++) + if (mtk_dp_rates[i] > max_rate) + break; + + source_caps->nlink_rates = i; + /* * Request the interrupt and install service routine only if we are * on full DisplayPort. @@ -2809,6 +2878,8 @@ static int mtk_dp_probe(struct platform_device *pdev) mtk_dp->bridge.of_node = dev->of_node; mtk_dp->bridge.type = mtk_dp->data->bridge_type; + mtk_dp->bridge.dp_link_caps = source_caps; + mtk_dp->bridge.ops = DRM_BRIDGE_OP_DP; if (mtk_dp->bridge.type == DRM_MODE_CONNECTOR_eDP) { /* @@ -2849,7 +2920,7 @@ static int mtk_dp_probe(struct platform_device *pdev) } } } else { - mtk_dp->bridge.ops = DRM_BRIDGE_OP_DETECT | + mtk_dp->bridge.ops |= DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_HPD; ret = devm_drm_bridge_add(dev, &mtk_dp->bridge); if (ret) -- 2.43.0