From patchwork Tue Aug 20 01:16:35 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laurent Pinchart X-Patchwork-Id: 11102453 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1375A1813 for ; Tue, 20 Aug 2019 01:17:49 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F128F2070B for ; Tue, 20 Aug 2019 01:17:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F128F2070B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E81696E50D; Tue, 20 Aug 2019 01:17:41 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5F7276E4A0 for ; Tue, 20 Aug 2019 01:17:37 +0000 (UTC) Received: from pendragon.bb.dnainternet.fi (dfj612yhrgyx302h3jwwy-3.rev.dnainternet.fi [IPv6:2001:14ba:21f5:5b00:ce28:277f:58d7:3ca4]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 75BDCAF9; Tue, 20 Aug 2019 03:17:34 +0200 (CEST) From: Laurent Pinchart To: dri-devel@lists.freedesktop.org Subject: [PATCH v2 04/50] drm/bridge: Add connector-related bridge operations and data Date: Tue, 20 Aug 2019 04:16:35 +0300 Message-Id: <20190820011721.30136-5-laurent.pinchart@ideasonboard.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190820011721.30136-1-laurent.pinchart@ideasonboard.com> References: <20190820011721.30136-1-laurent.pinchart@ideasonboard.com> MIME-Version: 1.0 X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1566263854; bh=ODd7Sqe0XkMPxOiQ2ngOY2b4q15sBzlotZyZTnCUrI0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iM7tPbl1alEwtmuUyGYoqyPfPnLc8Bg55qnW259nRaphOCaMjnRhtfHIjdZmg0gg0 yD8MYHsw0XZ7giJNiRweShGinZhxWGmCXD+sq5GIcbxpQXQ2YPtIySAh8Bv2IyU3o7 cE8opblpsn0457a1sgAolEUruFXYX8uwewhopDEQ= X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Maxime Ripard , Tomi Valkeinen , Sean Paul , Sebastian Reichel Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To support implementation of DRM connectors on top of DRM bridges instead of by bridges, the drm_bridge needs to expose new operations and data: - Output detection, hot-plug notification, mode retrieval and EDID retrieval operations - Bitmask of supported operations - Bridge output type - I2C adapter for DDC access Add and document these. Three new bridge helper functions are also added to handle hot plug notification in a way that is as transparent as possible for the bridges. Signed-off-by: Laurent Pinchart Reviewed-by: Boris Brezillon --- Changes since v1: - Make .hpd_enable() and .hpd_disable() optional - Rename .lost_hotplug() to .hpd_notify() - Add ddc field to drm_bridge --- drivers/gpu/drm/drm_bridge.c | 94 +++++++++++++++++++ include/drm/drm_bridge.h | 177 ++++++++++++++++++++++++++++++++++- 2 files changed, 270 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index cba537c99e43..cf1fbed88410 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -70,6 +70,8 @@ static LIST_HEAD(bridge_list); */ void drm_bridge_add(struct drm_bridge *bridge) { + mutex_init(&bridge->hpd_mutex); + mutex_lock(&bridge_lock); list_add_tail(&bridge->list, &bridge_list); mutex_unlock(&bridge_lock); @@ -86,6 +88,8 @@ void drm_bridge_remove(struct drm_bridge *bridge) mutex_lock(&bridge_lock); list_del_init(&bridge->list); mutex_unlock(&bridge_lock); + + mutex_destroy(&bridge->hpd_mutex); } EXPORT_SYMBOL(drm_bridge_remove); @@ -462,6 +466,96 @@ void drm_atomic_bridge_enable(struct drm_bridge *bridge, } EXPORT_SYMBOL(drm_atomic_bridge_enable); +/** + * drm_bridge_hpd_enable - enable hot plug detection for the bridge + * @bridge: bridge control structure + * @cb: hot-plug detection callback + * @data: data to be passed to the hot-plug detection callback + * + * Call &drm_bridge_funcs.hpd_enable if implemented and register the given @cb + * and @data as hot plug notification callback. From now on the @cb will be + * called with @data when an output status change is detected by the bridge, + * until hot plug notification gets disabled with drm_bridge_hpd_disable(). + * + * Hot plug detection is supported only if the DRM_BRIDGE_OP_HPD flag is set in + * bridge->ops. This function shall not be called when the flag is not set. + * + * Only one hot plug detection callback can be registered at a time, it is an + * error to call this function when hot plug detection is already enabled for + * the bridge. + */ +void drm_bridge_hpd_enable(struct drm_bridge *bridge, + void (*cb)(void *data, + enum drm_connector_status status), + void *data) +{ + if (!bridge || !(bridge->ops & DRM_BRIDGE_OP_HPD)) + return; + + mutex_lock(&bridge->hpd_mutex); + + if (WARN(bridge->hpd_cb, "Hot plug detection already enabled\n")) + goto unlock; + + bridge->hpd_cb = cb; + bridge->hpd_data = data; + + if (bridge->funcs->hpd_enable) + bridge->funcs->hpd_enable(bridge); + +unlock: + mutex_unlock(&bridge->hpd_mutex); +} +EXPORT_SYMBOL_GPL(drm_bridge_hpd_enable); + +/** + * drm_bridge_hpd_disable - disable hot plug detection for the bridge + * @bridge: bridge control structure + * + * Call &drm_bridge_funcs.hpd_disable if implemented and unregister the hot + * plug detection callback previously registered with drm_bridge_hpd_enable(). + * Once this function returns the callback will not be called by the bridge + * when an output status change occurs. + * + * Hot plug detection is supported only if the DRM_BRIDGE_OP_HPD flag is set in + * bridge->ops. This function shall not be called when the flag is not set. + */ +void drm_bridge_hpd_disable(struct drm_bridge *bridge) +{ + if (!bridge || !(bridge->ops & DRM_BRIDGE_OP_HPD)) + return; + + mutex_lock(&bridge->hpd_mutex); + if (bridge->funcs->hpd_disable) + bridge->funcs->hpd_disable(bridge); + + bridge->hpd_cb = NULL; + bridge->hpd_data = NULL; + mutex_unlock(&bridge->hpd_mutex); +} +EXPORT_SYMBOL_GPL(drm_bridge_hpd_disable); + +/** + * drm_bridge_hpd_notify - notify hot plug detection events + * @bridge: bridge control structure + * @status: output connection status + * + * Bridge drivers shall call this function to report hot plug events when they + * detect a change in the output status, when hot plug detection has been + * enabled by drm_bridge_hpd_enable(). + * + * This function shall be called in a context that can sleep. + */ +void drm_bridge_hpd_notify(struct drm_bridge *bridge, + enum drm_connector_status status) +{ + mutex_lock(&bridge->hpd_mutex); + if (bridge->hpd_cb) + bridge->hpd_cb(bridge->hpd_data, status); + mutex_unlock(&bridge->hpd_mutex); +} +EXPORT_SYMBOL_GPL(drm_bridge_hpd_notify); + #ifdef CONFIG_OF /** * of_drm_find_bridge - find the bridge corresponding to the device node in diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index 7616f6562fe4..7db6ca0fd75d 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -23,14 +23,16 @@ #ifndef __DRM_BRIDGE_H__ #define __DRM_BRIDGE_H__ -#include #include +#include +#include #include #include struct drm_bridge; struct drm_bridge_timings; struct drm_panel; +struct i2c_adapter; /** * struct drm_bridge_funcs - drm_bridge control functions @@ -334,6 +336,111 @@ struct drm_bridge_funcs { */ void (*atomic_post_disable)(struct drm_bridge *bridge, struct drm_atomic_state *state); + + /** + * @detect: + * + * Check if anything is attached to the bridge output. + * + * This callback is optional, if not implemented the bridge will be + * considered as always having a component attached to its output. + * Bridges that implement this callback shall set the + * DRM_BRIDGE_OP_DETECT flag in their &drm_bridge->ops. + * + * RETURNS: + * + * drm_connector_status indicating the bridge output status. + */ + enum drm_connector_status (*detect)(struct drm_bridge *bridge); + + /** + * @get_modes: + * + * Fill all modes currently valid for the sink into the &drm_connector + * with drm_mode_probed_add(). + * + * The @get_modes callback is mostly intended to support non-probable + * displays such as many fixed panels. Bridges that support reading + * EDID shall leave @get_modes unimplemented and implement the + * &drm_bridge_funcs->get_edid callback instead. + * + * This callback is optional. Bridges that implement it shall set the + * DRM_BRIDGE_OP_MODES flag in their &drm_bridge->ops. + * + * RETURNS: + * + * The number of modes added by calling drm_mode_probed_add(). + */ + int (*get_modes)(struct drm_bridge *bridge, + struct drm_connector *connector); + + /** + * @get_edid: + * + * Read and parse the EDID data of the connected display. + * + * The @get_edid callback is the preferred way of reporting mode + * information for a display connected to the bridge output. Bridges + * that support readind EDID shall implement this callback and leave + * the @get_modes callback unimplemented. + * + * The caller of this operation shall first verify the output + * connection status and refrain from reading EDID from a disconnected + * output. + * + * This callback is optional. Bridges that implement it shall set the + * DRM_BRIDGE_OP_EDID flag in their &drm_bridge->ops. + * + * RETURNS: + * + * An edid structure newly allocated with kmalloc() (or similar) on + * success, or NULL otherwise. The caller is responsible for freeing + * the returned edid structure with kfree(). + */ + struct edid *(*get_edid)(struct drm_bridge *bridge, + struct drm_connector *connector); + + /** + * @hpd_notify: + * + * Notify the bridge of hot plug detection. + * + * This callback is optional, it may be implemented by bridges that + * need to be notified of display connection or disconnection for + * internal reasons. One use case is to reset the internal state of CEC + * controllers for HDMI bridges. + */ + void (*hpd_notify)(struct drm_bridge *bridge, + enum drm_connector_status status); + + /** + * @hpd_enable: + * + * Enable hot plug detection. From now on the bridge shall call + * drm_bridge_hpd_notify() each time a change is detected in the output + * connection status, until hot plug detection gets disabled with + * @hpd_disable. + * + * This callback is optional and shall only be implemented by bridges + * that support hot-plug notification without polling. Bridges that + * implement it shall also implement the @hpd_disable callback and set + * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops. + */ + void (*hpd_enable)(struct drm_bridge *bridge); + + /** + * @hpd_disable: + * + * Disable hot plug detection. Once this function returns the bridge + * shall not call drm_bridge_hpd_notify() when a change in the output + * connection status occurs. + * + * This callback is optional and shall only be implemented by bridges + * that support hot-plug notification without polling. Bridges that + * implement it shall also implement the @hpd_enable callback and set + * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops. + */ + void (*hpd_disable)(struct drm_bridge *bridge); }; /** @@ -372,6 +479,39 @@ struct drm_bridge_timings { bool dual_link; }; +/** + * enum drm_bridge_ops - Bitmask of operations supported by the bridge + */ +enum drm_bridge_ops { + /** + * @DRM_BRIDGE_OP_DETECT: The bridge can detect displays connected to + * its output. Bridges that set this flag shall implement the + * &drm_bridge_funcs->detect callback. + */ + DRM_BRIDGE_OP_DETECT = BIT(0), + /** + * @DRM_BRIDGE_OP_EDID: The bridge can retrieve the EDID of the display + * connected to its output. Bridges that set this flag shall implement + * the &drm_bridge_funcs->get_edid callback. + */ + DRM_BRIDGE_OP_EDID = BIT(1), + /** + * @DRM_BRIDGE_OP_HPD: The bridge can detect hot-plug and hot-unplug + * without requiring polling. Bridges that set this flag shall + * implement the &drm_bridge_funcs->hpd_enable and + * &drm_bridge_funcs->hpd_disable callbacks if they support enabling + * and disabling hot-plug detection dynamically. + */ + DRM_BRIDGE_OP_HPD = BIT(2), + /** + * @DRM_BRIDGE_OP_MODES: The bridge can retrieving the modes supported + * by the display at its output. This does not include readind EDID + * which is separately covered by @DRM_BRIDGE_OP_EDID. Bridges that set + * this flag shall implement the &drm_bridge_funcs->get_modes callback. + */ + DRM_BRIDGE_OP_MODES = BIT(3), +}; + /** * struct drm_bridge - central DRM bridge control structure */ @@ -398,6 +538,33 @@ struct drm_bridge { const struct drm_bridge_funcs *funcs; /** @driver_private: pointer to the bridge driver's internal context */ void *driver_private; + /** @ops: bitmask of operations supported by the bridge */ + enum drm_bridge_ops ops; + /** + * @type: Type of the connection at the bridge output + * (DRM_MODE_CONNECTOR_*). For bridges at the end of this chain this + * identifies the type of connected display. + */ + int type; + /** + * @ddc: Associated I2C adapter for DDC access, if any. + */ + struct i2c_adapter *ddc; + /** private: */ + /** + * @hpd_mutex: Protects the @hpd_cb and @hpd_data fields. + */ + struct mutex hpd_mutex; + /** + * @hpd_cb: Hot plug detection callback, registered with + * drm_bridge_hpd_enable(). + */ + void (*hpd_cb)(void *data, enum drm_connector_status status); + /** + * @hpd_data: Private data passed to the Hot plug detection callback + * @hpd_cb. + */ + void *hpd_data; }; void drm_bridge_add(struct drm_bridge *bridge); @@ -428,6 +595,14 @@ void drm_atomic_bridge_pre_enable(struct drm_bridge *bridge, void drm_atomic_bridge_enable(struct drm_bridge *bridge, struct drm_atomic_state *state); +void drm_bridge_hpd_enable(struct drm_bridge *bridge, + void (*cb)(void *data, + enum drm_connector_status status), + void *data); +void drm_bridge_hpd_disable(struct drm_bridge *bridge); +void drm_bridge_hpd_notify(struct drm_bridge *bridge, + enum drm_connector_status status); + #ifdef CONFIG_DRM_PANEL_BRIDGE struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel, u32 connector_type);