1 files changed, 403 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/v4l2-mc.c b/drivers/media/v4l2-core/v4l2-mc.c
new file mode 100644
index 000000000000..2a7b79bc90fd
--- /dev/null
+++ b/drivers/media/v4l2-core/v4l2-mc.c
@@ -0,0 +1,403 @@
+/*
+ * Media Controller ancillary functions
+ *
+ * Copyright (c) 2016 Mauro Carvalho Chehab <mchehab@osg.samsung.com>
+ * Copyright (C) 2016 Shuah Khan <shuahkh@osg.samsung.com>
+ * Copyright (C) 2006-2010 Nokia Corporation
+ * Copyright (c) 2016 Intel Corporation.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/usb.h>
+#include <media/media-device.h>
+#include <media/media-entity.h>
+#include <media/v4l2-fh.h>
+#include <media/v4l2-mc.h>
+#include <media/v4l2-subdev.h>
+#include <media/media-device.h>
+#include <media/v4l2-mc.h>
+#include <media/videobuf2-core.h>
+
+int v4l2_mc_create_media_graph(struct media_device *mdev)
+
+{
+	struct media_entity *entity;
+	struct media_entity *if_vid = NULL, *if_aud = NULL;
+	struct media_entity *tuner = NULL, *decoder = NULL, *dtv_demod = NULL;
+	struct media_entity *io_v4l = NULL, *io_vbi = NULL, *io_swradio = NULL;
+	bool is_webcam = false;
+	u32 flags;
+	int ret;
+
+	if (!mdev)
+		return 0;
+
+	media_device_for_each_entity(entity, mdev) {
+		switch (entity->function) {
+		case MEDIA_ENT_F_IF_VID_DECODER:
+			if_vid = entity;
+			break;
+		case MEDIA_ENT_F_IF_AUD_DECODER:
+			if_aud = entity;
+			break;
+		case MEDIA_ENT_F_TUNER:
+			tuner = entity;
+			break;
+		case MEDIA_ENT_F_ATV_DECODER:
+			decoder = entity;
+			break;
+		case MEDIA_ENT_F_IO_V4L:
+			io_v4l = entity;
+			break;
+		case MEDIA_ENT_F_IO_VBI:
+			io_vbi = entity;
+			break;
+		case MEDIA_ENT_F_IO_SWRADIO:
+			io_swradio = entity;
+			break;
+		case MEDIA_ENT_F_CAM_SENSOR:
+			is_webcam = true;
+			break;
+		}
+	}
+
+	/* It should have at least one I/O entity */
+	if (!io_v4l && !io_vbi && !io_swradio)
+		return -EINVAL;
+
+	/*
+	 * Here, webcams are modelled on a very simple way: the sensor is
+	 * connected directly to the I/O entity. All dirty details, like
+	 * scaler and crop HW are hidden. While such mapping is not enough
+	 * for mc-centric hardware, it is enough for v4l2 interface centric
+	 * PC-consumer's hardware.
+	 */
+	if (is_webcam) {
+		if (!io_v4l)
+			return -EINVAL;
+
+		media_device_for_each_entity(entity, mdev) {
+			if (entity->function != MEDIA_ENT_F_CAM_SENSOR)
+				continue;
+			ret = media_create_pad_link(entity, 0,
+						    io_v4l, 0,
+						    MEDIA_LNK_FL_ENABLED);
+			if (ret)
+				return ret;
+		}
+		if (!decoder)
+			return 0;
+	}
+
+	/* The device isn't a webcam. So, it should have a decoder */
+	if (!decoder)
+		return -EINVAL;
+
+	/* Link the tuner and IF video output pads */
+	if (tuner) {
+		if (if_vid) {
+			ret = media_create_pad_link(tuner, TUNER_PAD_OUTPUT,
+						    if_vid,
+						    IF_VID_DEC_PAD_IF_INPUT,
+						    MEDIA_LNK_FL_ENABLED);
+			if (ret)
+				return ret;
+			ret = media_create_pad_link(if_vid, IF_VID_DEC_PAD_OUT,
+						decoder, DEMOD_PAD_IF_INPUT,
+						MEDIA_LNK_FL_ENABLED);
+			if (ret)
+				return ret;
+		} else {
+			ret = media_create_pad_link(tuner, TUNER_PAD_OUTPUT,
+						decoder, DEMOD_PAD_IF_INPUT,
+						MEDIA_LNK_FL_ENABLED);
+			if (ret)
+				return ret;
+		}
+
+		if (if_aud) {
+			ret = media_create_pad_link(tuner, TUNER_PAD_AUD_OUT,
+						    if_aud,
+						    IF_AUD_DEC_PAD_IF_INPUT,
+						    MEDIA_LNK_FL_ENABLED);
+			if (ret)
+				return ret;
+		} else {
+			if_aud = tuner;
+		}
+
+	}
+
+	/* Create demod to V4L, VBI and SDR radio links */
+	if (io_v4l) {
+		ret = media_create_pad_link(decoder, DEMOD_PAD_VID_OUT,
+					io_v4l, 0,
+					MEDIA_LNK_FL_ENABLED);
+		if (ret)
+			return ret;
+	}
+
+	if (io_swradio) {
+		ret = media_create_pad_link(decoder, DEMOD_PAD_VID_OUT,
+					io_swradio, 0,
+					MEDIA_LNK_FL_ENABLED);
+		if (ret)
+			return ret;
+	}
+
+	if (io_vbi) {
+		ret = media_create_pad_link(decoder, DEMOD_PAD_VBI_OUT,
+					    io_vbi, 0,
+					    MEDIA_LNK_FL_ENABLED);
+		if (ret)
+			return ret;
+	}
+
+	/* Create links for the media connectors */
+	flags = MEDIA_LNK_FL_ENABLED;
+	media_device_for_each_entity(entity, mdev) {
+		switch (entity->function) {
+		case MEDIA_ENT_F_CONN_RF:
+			if (!tuner)
+				continue;
+
+			ret = media_create_pad_link(entity, 0, tuner,
+						    TUNER_PAD_RF_INPUT,
+						    flags);
+			break;
+		case MEDIA_ENT_F_CONN_SVIDEO:
+		case MEDIA_ENT_F_CONN_COMPOSITE:
+			ret = media_create_pad_link(entity, 0, decoder,
+						    DEMOD_PAD_IF_INPUT,
+						    flags);
+			break;
+		default:
+			continue;
+		}
+		if (ret)
+			return ret;
+
+		flags = 0;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_mc_create_media_graph);
+
+int v4l_enable_media_source(struct video_device *vdev)
+{
+	struct media_device *mdev = vdev->entity.graph_obj.mdev;
+	int ret;
+
+	if (!mdev || !mdev->enable_source)
+		return 0;
+	ret = mdev->enable_source(&vdev->entity, &vdev->pipe);
+	if (ret)
+		return -EBUSY;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(v4l_enable_media_source);
+
+void v4l_disable_media_source(struct video_device *vdev)
+{
+	struct media_device *mdev = vdev->entity.graph_obj.mdev;
+
+	if (mdev && mdev->disable_source)
+		mdev->disable_source(&vdev->entity);
+}
+EXPORT_SYMBOL_GPL(v4l_disable_media_source);
+
+int v4l_vb2q_enable_media_source(struct vb2_queue *q)
+{
+	struct v4l2_fh *fh = q->owner;
+
+	if (fh && fh->vdev)
+		return v4l_enable_media_source(fh->vdev);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(v4l_vb2q_enable_media_source);
+
+/* -----------------------------------------------------------------------------
+ * Pipeline power management
+ *
+ * Entities must be powered up when part of a pipeline that contains at least
+ * one open video device node.
+ *
+ * To achieve this use the entity use_count field to track the number of users.
+ * For entities corresponding to video device nodes the use_count field stores
+ * the users count of the node. For entities corresponding to subdevs the
+ * use_count field stores the total number of users of all video device nodes
+ * in the pipeline.
+ *
+ * The v4l2_pipeline_pm_use() function must be called in the open() and
+ * close() handlers of video device nodes. It increments or decrements the use
+ * count of all subdev entities in the pipeline.
+ *
+ * To react to link management on powered pipelines, the link setup notification
+ * callback updates the use count of all entities in the source and sink sides
+ * of the link.
+ */
+
+/*
+ * pipeline_pm_use_count - Count the number of users of a pipeline
+ * @entity: The entity
+ *
+ * Return the total number of users of all video device nodes in the pipeline.
+ */
+static int pipeline_pm_use_count(struct media_entity *entity,
+	struct media_entity_graph *graph)
+{
+	int use = 0;
+
+	media_entity_graph_walk_start(graph, entity);
+
+	while ((entity = media_entity_graph_walk_next(graph))) {
+		if (is_media_entity_v4l2_io(entity))
+			use += entity->use_count;
+	}
+
+	return use;
+}
+
+/*
+ * pipeline_pm_power_one - Apply power change to an entity
+ * @entity: The entity
+ * @change: Use count change
+ *
+ * Change the entity use count by @change. If the entity is a subdev update its
+ * power state by calling the core::s_power operation when the use count goes
+ * from 0 to != 0 or from != 0 to 0.
+ *
+ * Return 0 on success or a negative error code on failure.
+ */
+static int pipeline_pm_power_one(struct media_entity *entity, int change)
+{
+	struct v4l2_subdev *subdev;
+	int ret;
+
+	subdev = is_media_entity_v4l2_subdev(entity)
+	       ? media_entity_to_v4l2_subdev(entity) : NULL;
+
+	if (entity->use_count == 0 && change > 0 && subdev != NULL) {
+		ret = v4l2_subdev_call(subdev, core, s_power, 1);
+		if (ret < 0 && ret != -ENOIOCTLCMD)
+			return ret;
+	}
+
+	entity->use_count += change;
+	WARN_ON(entity->use_count < 0);
+
+	if (entity->use_count == 0 && change < 0 && subdev != NULL)
+		v4l2_subdev_call(subdev, core, s_power, 0);
+
+	return 0;
+}
+
+/*
+ * pipeline_pm_power - Apply power change to all entities in a pipeline
+ * @entity: The entity
+ * @change: Use count change
+ *
+ * Walk the pipeline to update the use count and the power state of all non-node
+ * entities.
+ *
+ * Return 0 on success or a negative error code on failure.
+ */
+static int pipeline_pm_power(struct media_entity *entity, int change,
+	struct media_entity_graph *graph)
+{
+	struct media_entity *first = entity;
+	int ret = 0;
+
+	if (!change)
+		return 0;
+
+	media_entity_graph_walk_start(graph, entity);
+
+	while (!ret && (entity = media_entity_graph_walk_next(graph)))
+		if (is_media_entity_v4l2_subdev(entity))
+			ret = pipeline_pm_power_one(entity, change);
+
+	if (!ret)
+		return ret;
+
+	media_entity_graph_walk_start(graph, first);
+
+	while ((first = media_entity_graph_walk_next(graph))
+	       && first != entity)
+		if (is_media_entity_v4l2_subdev(first))
+			pipeline_pm_power_one(first, -change);
+
+	return ret;
+}
+
+int v4l2_pipeline_pm_use(struct media_entity *entity, int use)
+{
+	struct media_device *mdev = entity->graph_obj.mdev;
+	int change = use ? 1 : -1;
+	int ret;
+
+	mutex_lock(&mdev->graph_mutex);
+
+	/* Apply use count to node. */
+	entity->use_count += change;
+	WARN_ON(entity->use_count < 0);
+
+	/* Apply power change to connected non-nodes. */
+	ret = pipeline_pm_power(entity, change, &mdev->pm_count_walk);
+	if (ret < 0)
+		entity->use_count -= change;
+
+	mutex_unlock(&mdev->graph_mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(v4l2_pipeline_pm_use);
+
+int v4l2_pipeline_link_notify(struct media_link *link, u32 flags,
+			      unsigned int notification)
+{
+	struct media_entity_graph *graph = &link->graph_obj.mdev->pm_count_walk;
+	struct media_entity *source = link->source->entity;
+	struct media_entity *sink = link->sink->entity;
+	int source_use;
+	int sink_use;
+	int ret = 0;
+
+	source_use = pipeline_pm_use_count(source, graph);
+	sink_use = pipeline_pm_use_count(sink, graph);
+
+	if (notification == MEDIA_DEV_NOTIFY_POST_LINK_CH &&
+	    !(flags & MEDIA_LNK_FL_ENABLED)) {
+		/* Powering off entities is assumed to never fail. */
+		pipeline_pm_power(source, -sink_use, graph);
+		pipeline_pm_power(sink, -source_use, graph);
+		return 0;
+	}
+
+	if (notification == MEDIA_DEV_NOTIFY_PRE_LINK_CH &&
+		(flags & MEDIA_LNK_FL_ENABLED)) {
+
+		ret = pipeline_pm_power(source, sink_use, graph);
+		if (ret < 0)
+			return ret;
+
+		ret = pipeline_pm_power(sink, source_use, graph);
+		if (ret < 0)
+			pipeline_pm_power(source, -sink_use, graph);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(v4l2_pipeline_link_notify);