From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) (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 06E4A4BD366; Mon, 21 Sep 2026 15:53:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.112 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790005998; cv=pass; b=oeCuUM7Vs+QwaV3oD/1+hq+ZJjUB2qp3Iq662QNaQcaQ9qZTY8E94/ZYWif7FS3caHgilcWtCl1S4KWW9/qSdEUZ+2MJWgMj2kYpIygjskFojqDfuxJF1nvZdpZ2zOWyYxwRIerfGxY634cqmqQMw32LLmTnBMh19he6pGXinuk= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790005998; c=relaxed/simple; bh=PVwmAzt9UOSomrJzODsMy/tXZYNwc2/OR/5WOAK5PIs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=OZyXJcdiS/3psfYuG+bWHPumO1/S1i4yRWqz9maFccs6GzJ0a6LWSfVCd34WMJg5PYk8+LDzIpFym6Rk7VCWoqg1QIKlvUxD9MuGAgZb7gQgMBZm7U8cmfSbmNQdik4vUNirK2oY4YdiykunNDo+LSX4jTNxGI+BQej8GvKFNFw= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=nicolas.frattaroli@collabora.com header.b=GB3YC3I9; arc=pass smtp.client-ip=136.143.188.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=nicolas.frattaroli@collabora.com header.b="GB3YC3I9" ARC-Seal: i=1; a=rsa-sha256; t=1790005951; cv=none; d=zohomail.com; s=zohoarc; b=hJuEk/WXya3YSJ7LhRNDAFC1MHk9GtJeimnQ9ZLklDsPCi5INcsGyqoU7YgcuhI7RBUxaXaqlJ3LHlPHmnGCWeM2uwgW/mECm/ln4HEUwduM+kC1fbuy3Pgn+oLskBhtNTPSeuARsQ4ndvdFDYRHoaTWOPPgYBNmob8yO5dSGt0= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1790005951; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=CnFGpLHNPi3LH+koDqB85QbgcIXof8AnqDGa7CUOj4Y=; b=XRyI1gaI3qZ5mlYUnApgcWa77UECg29xCk/fMKtOFf6Rhhb/vnzuer+HUkTMk/PBB8cKMd6bKYvZ61ymabJ6HDBQ6XP9XiuTEhHUDkkfAvxgll9m1KxpH8Nm4TNRAiKCU2MjH9KDlinUTxB0Wp9QJJz6Z6le5U3fpUz3uiFuZxk= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=nicolas.frattaroli@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1790005951; s=zohomail; d=collabora.com; i=nicolas.frattaroli@collabora.com; h=From:From:Date:Date:Subject:Subject:MIME-Version:Content-Type:Content-Transfer-Encoding:Message-Id:Message-Id:In-Reply-To:To:To:Cc:Cc:Reply-To; bh=CnFGpLHNPi3LH+koDqB85QbgcIXof8AnqDGa7CUOj4Y=; b=GB3YC3I9oUKWLc+A3JSbQ48WwIo5d3RbvksvfstgfXM1HSWAKqCwNK0rCMBOL4Gw TsY1K2CHvLXJ3mb9hg3MUwGK9dxRvZDh630zLevo5MT5M2VAWLhqC7YpdNH3V4G/5GJ 0DwfxoFydSyH/9Jwtr5kFfxj/gSbxl5zTPT1LNqA= Received: by smtp.zohomail.com with SMTPS id 1790005949614805.1464665003713; Mon, 21 Sep 2026 08:52:29 -0700 (PDT) From: Nicolas Frattaroli Date: Mon, 21 Sep 2026 17:51:31 +0200 Subject: [PATCH RFC 05/25] drm/bridge: Add VTEM EMP support 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: <20260921-vrr-limiter-uapi-v1-5-2fcd7d011646@collabora.com> References: <20260921-vrr-limiter-uapi-v1-0-2fcd7d011646@collabora.com> In-Reply-To: <20260921-vrr-limiter-uapi-v1-0-2fcd7d011646@collabora.com> To: "Borah, Chaitanya Kumar" , Leo Li , Daniel Stone , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Helge Deller , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Luca Ceresoli , Sandy Huang , =?utf-8?q?Heiko_St=C3=BCbner?= , Andy Yan Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, kernel@collabora.com, Derek Foreman , wayland-devel@lists.freedesktop.org, Nicolas Frattaroli X-Mailer: b4 0.15.2 From: Derek Foreman Add setters and support bit for VTEM emp to the bridge. Signed-off-by: Derek Foreman --- drivers/gpu/drm/display/drm_bridge_connector.c | 41 ++++++++++++++++++++++++++ include/drm/drm_bridge.h | 29 ++++++++++++++++++ include/drm/drm_connector.h | 8 +++++ 3 files changed, 78 insertions(+) diff --git a/drivers/gpu/drm/display/drm_bridge_connector.c b/drivers/gpu/drm/display/drm_bridge_connector.c index 707d7143e475..dc814dbb5120 100644 --- a/drivers/gpu/drm/display/drm_bridge_connector.c +++ b/drivers/gpu/drm/display/drm_bridge_connector.c @@ -610,6 +610,33 @@ static int drm_bridge_connector_scrambler_disable(struct drm_connector *connecto return bridge->funcs->hdmi_scrambler_disable(bridge); } +static int drm_bridge_connector_clear_vtem_emp(struct drm_connector *connector) +{ + struct drm_bridge_connector *bridge_connector = + to_drm_bridge_connector(connector); + struct drm_bridge *bridge; + + bridge = bridge_connector->bridge_hdmi; + if (!bridge) + return -EINVAL; + + return bridge->funcs->hdmi_clear_vtem_emp(bridge); +} + +static int drm_bridge_connector_write_vtem_emp(struct drm_connector *connector, + const u8 *buffer, size_t len) +{ + struct drm_bridge_connector *bridge_connector = + to_drm_bridge_connector(connector); + struct drm_bridge *bridge; + + bridge = bridge_connector->bridge_hdmi; + if (!bridge) + return -EINVAL; + + return bridge->funcs->hdmi_write_vtem_emp(bridge, buffer, len); +} + static const struct drm_edid * drm_bridge_connector_read_edid(struct drm_connector *connector) { @@ -655,6 +682,11 @@ static const struct drm_connector_infoframe_funcs drm_bridge_connector_hdmi_spd_ .write_infoframe = drm_bridge_connector_write_spd_infoframe, }; +static const struct drm_connector_infoframe_funcs drm_bridge_connector_hdmi_vtem_emp = { + .clear_infoframe = drm_bridge_connector_clear_vtem_emp, + .write_infoframe = drm_bridge_connector_write_vtem_emp, +}; + static int drm_bridge_connector_audio_startup(struct drm_connector *connector) { struct drm_bridge_connector *bridge_connector = @@ -946,6 +978,11 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm, !bridge->funcs->hdmi_scrambler_disable)) return ERR_PTR(-EINVAL); + if (bridge->ops & DRM_BRIDGE_OP_HDMI_VTEM_EMP && + (!bridge->funcs->hdmi_write_vtem_emp || + !bridge->funcs->hdmi_clear_vtem_emp)) + return ERR_PTR(-EINVAL); + bridge_connector->bridge_hdmi = drm_bridge_get(bridge); } @@ -1072,6 +1109,10 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm, drm_bridge_connector_scrambler_disable; } + if (bridge_connector->bridge_hdmi->ops & DRM_BRIDGE_OP_HDMI_VTEM_EMP) + bridge_connector->hdmi_funcs.vtem = + drm_bridge_connector_hdmi_vtem_emp; + ret = drmm_connector_hdmi_init(drm, connector, &drm_bridge_connector_funcs, &bridge_connector->hdmi_funcs, diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index 77b3ffe69230..9dbd1bfa39af 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -684,6 +684,29 @@ struct drm_bridge_funcs { int (*hdmi_write_spd_infoframe)(struct drm_bridge *bridge, const u8 *buffer, size_t len); + /** + * @hdmi_clear_vtem_emp: + * + * This callback clears the emp in the hardware during commit. + * + * This callback is optional but it must be implemented by bridges that + * set the DRM_BRIDGE_OP_HDMI_VTEM_EMP flag in their + * &drm_bridge->ops. + */ + int (*hdmi_clear_vtem_emp)(struct drm_bridge *bridge); + + /** + * @hdmi_write_spd_infoframe: + * + * Program the emp into the hardware. + * + * This callback is optional but it must be implemented by bridges that + * set the DRM_BRIDGE_OP_HDMI_VTEM_EMP flag in their + * &drm_bridge->ops. + */ + int (*hdmi_write_vtem_emp)(struct drm_bridge *bridge, + const u8 *buffer, size_t len); + /** * @hdmi_clear_audio_infoframe: * @@ -1021,6 +1044,12 @@ enum drm_bridge_ops { * &drm_bridge_funcs->hdmi_clear_spd_infoframe callbacks. */ DRM_BRIDGE_OP_HDMI_SPD_INFOFRAME = BIT(10), + /** + * @DRM_BRIDGE_OP_HDMI_VTEM_EMP: The bridge supports + * &drm_bridge_funcs->hdmi_write_vtem_emp and + * &drm_bridge_funcs->hdmi_clear_vtem_emp callbacks. + */ + DRM_BRIDGE_OP_HDMI_VTEM_EMP = BIT(11), }; /** diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h index 593fbeaffa16..e561a444515f 100644 --- a/include/drm/drm_connector.h +++ b/include/drm/drm_connector.h @@ -1633,6 +1633,14 @@ struct drm_connector_hdmi_funcs { * optional. */ struct drm_connector_infoframe_funcs spd; + + /** + * @vtem: + * + * Set of callbacks for handling the VTEM EMP. These callbacks are + * optional. + */ + struct drm_connector_infoframe_funcs vtem; }; /** -- 2.55.0