diff mbox series

[RFCv3,2/3] media controller: add properties support

Message ID 20180928100745.4946-3-hverkuil@xs4all.nl (mailing list archive)
State New, archived
Headers show
Series Media Controller Properties | expand

Commit Message

Hans Verkuil Sept. 28, 2018, 10:07 a.m. UTC
From: Hans Verkuil <hans.verkuil@cisco.com>

Add support for properties. In this initial implementation properties
can be added to entities and pads. In addition, properties can be
nested.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
---
 drivers/media/media-device.c | 324 +++++++++++++++++++++++++++--------
 drivers/media/media-entity.c | 107 +++++++++++-
 include/media/media-device.h |   6 +
 include/media/media-entity.h | 315 ++++++++++++++++++++++++++++++++++
 4 files changed, 672 insertions(+), 80 deletions(-)
diff mbox series

Patch

diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c
index 4c7190db420e..0eb0f0b4b72e 100644
--- a/drivers/media/media-device.c
+++ b/drivers/media/media-device.c
@@ -234,6 +234,21 @@  static long media_device_setup_link(struct media_device *mdev, void *arg)
 	return __media_entity_setup_link(link, linkd->flags);
 }
 
+static void walk_props(struct list_head *head, u32 *prop_idx, u32 *payload_size)
+{
+	struct media_prop *prop;
+
+	if (list_empty(head))
+		return;
+
+	list_for_each_entry(prop, head, list) {
+		prop->graph_obj.topology_idx = (*prop_idx)++;
+		*payload_size += prop->payload_size;
+	}
+	list_for_each_entry(prop, head, list)
+		walk_props(&prop->props, prop_idx, payload_size);
+}
+
 static long media_device_get_topology(struct media_device *mdev, void *arg)
 {
 	struct media_v2_topology *topo = arg;
@@ -241,27 +256,95 @@  static long media_device_get_topology(struct media_device *mdev, void *arg)
 	struct media_interface *intf;
 	struct media_pad *pad;
 	struct media_link *link;
+	struct media_prop *prop, *subprop;
 	struct media_v2_entity kentity, __user *uentity;
 	struct media_v2_interface kintf, __user *uintf;
 	struct media_v2_pad kpad, __user *upad;
 	struct media_v2_link klink, __user *ulink;
+	struct media_v2_prop kprop, __user *uprop;
+	u32 payload_size = 0;
+	u32 payload_offset = 0;
+	u32 entity_idx = 0;
+	u32 interface_idx = 0;
+	u32 pad_idx = 0;
+	u32 link_idx = 0;
+	u32 prop_idx = 0;
 	unsigned int i;
 	int ret = 0;
 
 	topo->topology_version = mdev->topology_version;
 
+	/* Set entity/pad/link indices and number of entities */
+	media_device_for_each_entity(entity, mdev) {
+		entity->graph_obj.topology_idx = entity_idx++;
+		walk_props(&entity->props, &prop_idx, &payload_size);
+		for (i = 0; i < entity->num_pads; i++) {
+			pad = entity->pads + i;
+			pad->graph_obj.topology_idx = pad_idx++;
+			walk_props(&pad->props, &prop_idx, &payload_size);
+		}
+		/* Note: links are ordered by source pad index */
+		list_for_each_entry(link, &entity->links, list)
+			link->graph_obj.topology_idx = link_idx++;
+	}
+	if (topo->ptr_entities && entity_idx > topo->num_entities)
+		ret = -ENOSPC;
+	topo->num_entities = entity_idx;
+	topo->reserved1 = 0;
+
+	/* Set interface/link indices and number of interfaces */
+	media_device_for_each_intf(intf, mdev) {
+		intf->graph_obj.topology_idx = interface_idx++;
+		list_for_each_entry(link, &intf->links, list)
+			link->graph_obj.topology_idx = link_idx++;
+	}
+
+	if (topo->ptr_interfaces && interface_idx > topo->num_interfaces)
+		ret = -ENOSPC;
+	topo->num_interfaces = interface_idx;
+	topo->reserved2 = 0;
+
+	/* Set number of pads */
+	if (topo->ptr_pads && pad_idx > topo->num_pads)
+		ret = -ENOSPC;
+	topo->num_pads = pad_idx;
+	topo->reserved3 = 0;
+
+	/* Set number of links */
+	if (topo->ptr_links && link_idx > topo->num_links)
+		ret = -ENOSPC;
+	topo->num_links = link_idx;
+	topo->reserved4 = 0;
+
+	/* Set number of properties */
+	if (topo->ptr_props &&
+	    (prop_idx > topo->num_props ||
+	     payload_size > topo->props_payload_size))
+		ret = -ENOSPC;
+	topo->num_props = prop_idx;
+	topo->props_payload_size = payload_size;
+
+	if (ret)
+		return ret;
+
+	/*
+	 * We use u16 for the graph object indices,
+	 * so check that it will fit in 16 bits.
+	 */
+	if (WARN_ON(entity_idx >= 0x10000 ||
+		    interface_idx >= 0x10000 ||
+		    pad_idx >= 0x10000 ||
+		    link_idx >= 0x10000 ||
+		    prop_idx >= 0x10000))
+		return -EINVAL;
+
 	/* Get entities and number of entities */
-	i = 0;
 	uentity = media_get_uptr(topo->ptr_entities);
-	media_device_for_each_entity(entity, mdev) {
-		i++;
-		if (ret || !uentity)
-			continue;
+	if (!uentity)
+		goto skip_entities;
 
-		if (i > topo->num_entities) {
-			ret = -ENOSPC;
-			continue;
-		}
+	media_device_for_each_entity(entity, mdev) {
+		u16 idx = entity->graph_obj.topology_idx;
 
 		/* Copy fields to userspace struct if not error */
 		memset(&kentity, 0, sizeof(kentity));
@@ -269,27 +352,30 @@  static long media_device_get_topology(struct media_device *mdev, void *arg)
 		kentity.function = entity->function;
 		kentity.flags = entity->flags;
 		strscpy(kentity.name, entity->name,
-			sizeof(kentity.name));
+				sizeof(kentity.name));
+		if (entity->num_pads) {
+			kentity.pad_idx = entity->pads[0].graph_obj.topology_idx;
+			kentity.flags |= MEDIA_ENT_FL_PAD_IDX;
+		}
+		if (!list_empty(&entity->props)) {
+			prop = list_first_entry(&entity->props,
+						struct media_prop, list);
+			kentity.prop_idx = prop->graph_obj.topology_idx;
+			kentity.flags |= MEDIA_ENT_FL_PROP_IDX;
+		}
 
-		if (copy_to_user(uentity, &kentity, sizeof(kentity)))
-			ret = -EFAULT;
-		uentity++;
+		if (copy_to_user(uentity + idx, &kentity, sizeof(kentity)))
+			return -EFAULT;
 	}
-	topo->num_entities = i;
-	topo->reserved1 = 0;
+skip_entities:
 
 	/* Get interfaces and number of interfaces */
-	i = 0;
 	uintf = media_get_uptr(topo->ptr_interfaces);
-	media_device_for_each_intf(intf, mdev) {
-		i++;
-		if (ret || !uintf)
-			continue;
+	if (!uintf)
+		goto skip_interfaces;
 
-		if (i > topo->num_interfaces) {
-			ret = -ENOSPC;
-			continue;
-		}
+	media_device_for_each_intf(intf, mdev) {
+		u16 idx = intf->graph_obj.topology_idx;
 
 		memset(&kintf, 0, sizeof(kintf));
 
@@ -297,6 +383,12 @@  static long media_device_get_topology(struct media_device *mdev, void *arg)
 		kintf.id = intf->graph_obj.id;
 		kintf.intf_type = intf->type;
 		kintf.flags = intf->flags;
+		if (!list_empty(&intf->links)) {
+			link = list_first_entry(&intf->links,
+						struct media_link, list);
+			kintf.link_idx = link->graph_obj.topology_idx;
+			kintf.flags |= MEDIA_INTF_FL_LINK_IDX;
+		}
 
 		if (media_type(&intf->graph_obj) == MEDIA_GRAPH_INTF_DEVNODE) {
 			struct media_intf_devnode *devnode;
@@ -307,25 +399,18 @@  static long media_device_get_topology(struct media_device *mdev, void *arg)
 			kintf.devnode.minor = devnode->minor;
 		}
 
-		if (copy_to_user(uintf, &kintf, sizeof(kintf)))
-			ret = -EFAULT;
-		uintf++;
+		if (copy_to_user(uintf + idx, &kintf, sizeof(kintf)))
+			return -EFAULT;
 	}
-	topo->num_interfaces = i;
-	topo->reserved2 = 0;
+skip_interfaces:
 
 	/* Get pads and number of pads */
-	i = 0;
 	upad = media_get_uptr(topo->ptr_pads);
-	media_device_for_each_pad(pad, mdev) {
-		i++;
-		if (ret || !upad)
-			continue;
+	if (!upad)
+		goto skip_pads;
 
-		if (i > topo->num_pads) {
-			ret = -ENOSPC;
-			continue;
-		}
+	media_device_for_each_pad(pad, mdev) {
+		u16 idx = pad->graph_obj.topology_idx;
 
 		memset(&kpad, 0, sizeof(kpad));
 
@@ -335,29 +420,37 @@  static long media_device_get_topology(struct media_device *mdev, void *arg)
 		kpad.flags = pad->flags;
 		kpad.index = pad->index;
 
-		if (copy_to_user(upad, &kpad, sizeof(kpad)))
-			ret = -EFAULT;
-		upad++;
+		entity = pad->entity;
+		list_for_each_entry(link, &entity->links, list) {
+			if (link->source == pad) {
+				kpad.link_idx = link->graph_obj.topology_idx;
+				kpad.flags |= MEDIA_PAD_FL_LINK_IDX;
+				break;
+			}
+		}
+		if (!list_empty(&pad->props)) {
+			prop = list_first_entry(&pad->props,
+						struct media_prop, list);
+			kpad.prop_idx = prop->graph_obj.topology_idx;
+			kpad.flags |= MEDIA_PAD_FL_PROP_IDX;
+		}
+
+		if (copy_to_user(upad + idx, &kpad, sizeof(kpad)))
+			return -EFAULT;
 	}
-	topo->num_pads = i;
-	topo->reserved3 = 0;
+skip_pads:
 
 	/* Get links and number of links */
-	i = 0;
 	ulink = media_get_uptr(topo->ptr_links);
-	media_device_for_each_link(link, mdev) {
-		if (link->is_backlink)
-			continue;
-
-		i++;
+	if (!ulink)
+		goto skip_links;
 
-		if (ret || !ulink)
-			continue;
+	media_device_for_each_link(link, mdev) {
+		u16 idx;
 
-		if (i > topo->num_links) {
-			ret = -ENOSPC;
+		if (link->is_backlink)
 			continue;
-		}
+		idx = link->graph_obj.topology_idx;
 
 		memset(&klink, 0, sizeof(klink));
 
@@ -367,14 +460,47 @@  static long media_device_get_topology(struct media_device *mdev, void *arg)
 		klink.sink_id = link->gobj1->id;
 		klink.flags = link->flags;
 
-		if (copy_to_user(ulink, &klink, sizeof(klink)))
-			ret = -EFAULT;
-		ulink++;
+		if (copy_to_user(ulink + idx, &klink, sizeof(klink)))
+			return -EFAULT;
 	}
-	topo->num_links = i;
-	topo->reserved4 = 0;
+skip_links:
+
+	/* Get properties and number of properties */
+	uprop = media_get_uptr(topo->ptr_props);
+	if (!uprop)
+		goto skip_props;
+
+	payload_offset = topo->num_props * sizeof(*uprop);
+	media_device_for_each_prop(prop, mdev) {
+		u16 idx = prop->graph_obj.topology_idx;
+
+		memset(&kprop, 0, sizeof(kprop));
+
+		/* Copy prop fields to userspace struct */
+		kprop.id = prop->graph_obj.id;
+		kprop.owner_id = prop->owner->id;
+		kprop.type = prop->type;
+		kprop.flags = 0;
+		kprop.payload_size = prop->payload_size;
+		kprop.payload_offset = payload_offset - idx * sizeof(*uprop);
+		memcpy(kprop.name, prop->name, sizeof(kprop.name));
+		if (!list_empty(&prop->props)) {
+			subprop = list_first_entry(&prop->props,
+						   struct media_prop, list);
+			kprop.prop_idx = subprop->graph_obj.topology_idx;
+			kprop.flags |= MEDIA_PROP_FL_PROP_IDX;
+		}
 
-	return ret;
+		if (copy_to_user(uprop + idx, &kprop, sizeof(kprop)))
+			return -EFAULT;
+		if (copy_to_user((u8 __user *)uprop + payload_offset,
+				 prop->payload, prop->payload_size))
+			return -EFAULT;
+		payload_offset += prop->payload_size;
+	}
+skip_props:
+
+	return 0;
 }
 
 static long copy_arg_from_user(void *karg, void __user *uarg, unsigned int cmd)
@@ -398,9 +524,10 @@  static long copy_arg_to_user(void __user *uarg, void *karg, unsigned int cmd)
 /* Do acquire the graph mutex */
 #define MEDIA_IOC_FL_GRAPH_MUTEX	BIT(0)
 
-#define MEDIA_IOC_ARG(__cmd, func, fl, from_user, to_user)		\
+#define MEDIA_IOC_ARG(__cmd, alts, func, fl, from_user, to_user)	\
 	[_IOC_NR(MEDIA_IOC_##__cmd)] = {				\
 		.cmd = MEDIA_IOC_##__cmd,				\
+		.alternatives = (alts),					\
 		.fn = (long (*)(struct media_device *, void *))func,	\
 		.flags = fl,						\
 		.arg_from_user = from_user,				\
@@ -408,23 +535,32 @@  static long copy_arg_to_user(void __user *uarg, void *karg, unsigned int cmd)
 	}
 
 #define MEDIA_IOC(__cmd, func, fl)					\
-	MEDIA_IOC_ARG(__cmd, func, fl, copy_arg_from_user, copy_arg_to_user)
+	MEDIA_IOC_ARG(__cmd, NULL, func, fl, copy_arg_from_user, copy_arg_to_user)
+#define MEDIA_IOC_ALTS(__cmd, alts, func, fl)				\
+	MEDIA_IOC_ARG(__cmd, alts, func, fl, copy_arg_from_user, copy_arg_to_user)
 
 /* the table is indexed by _IOC_NR(cmd) */
 struct media_ioctl_info {
 	unsigned int cmd;
+	const unsigned int *alternatives;
 	unsigned short flags;
 	long (*fn)(struct media_device *dev, void *arg);
 	long (*arg_from_user)(void *karg, void __user *uarg, unsigned int cmd);
 	long (*arg_to_user)(void __user *uarg, void *karg, unsigned int cmd);
 };
 
+static const unsigned int topo_alts[] = {
+	/* Old MEDIA_IOC_G_TOPOLOGY without props support */
+	MEDIA_IOC_G_TOPOLOGY_OLD,
+	0
+};
+
 static const struct media_ioctl_info ioctl_info[] = {
 	MEDIA_IOC(DEVICE_INFO, media_device_get_info, MEDIA_IOC_FL_GRAPH_MUTEX),
 	MEDIA_IOC(ENUM_ENTITIES, media_device_enum_entities, MEDIA_IOC_FL_GRAPH_MUTEX),
 	MEDIA_IOC(ENUM_LINKS, media_device_enum_links, MEDIA_IOC_FL_GRAPH_MUTEX),
 	MEDIA_IOC(SETUP_LINK, media_device_setup_link, MEDIA_IOC_FL_GRAPH_MUTEX),
-	MEDIA_IOC(G_TOPOLOGY, media_device_get_topology, MEDIA_IOC_FL_GRAPH_MUTEX),
+	MEDIA_IOC_ALTS(G_TOPOLOGY, topo_alts, media_device_get_topology, MEDIA_IOC_FL_GRAPH_MUTEX),
 };
 
 static long media_device_ioctl(struct file *filp, unsigned int cmd,
@@ -437,17 +573,29 @@  static long media_device_ioctl(struct file *filp, unsigned int cmd,
 	char __karg[256], *karg = __karg;
 	long ret;
 
-	if (_IOC_NR(cmd) >= ARRAY_SIZE(ioctl_info)
-	    || ioctl_info[_IOC_NR(cmd)].cmd != cmd)
+	if (_IOC_NR(cmd) >= ARRAY_SIZE(ioctl_info))
 		return -ENOIOCTLCMD;
 
 	info = &ioctl_info[_IOC_NR(cmd)];
 
+	if (info->cmd != cmd) {
+		const unsigned int *p;
+
+		for (p = info->alternatives; p && *p; p++)
+			if (*p == cmd)
+				break;
+		if (!p || !*p)
+			return -ENOIOCTLCMD;
+	}
+
 	if (_IOC_SIZE(info->cmd) > sizeof(__karg)) {
 		karg = kmalloc(_IOC_SIZE(info->cmd), GFP_KERNEL);
 		if (!karg)
 			return -ENOMEM;
 	}
+	if (_IOC_SIZE(info->cmd) > _IOC_SIZE(cmd))
+		memset(karg + _IOC_SIZE(cmd), 0,
+		       _IOC_SIZE(info->cmd) - _IOC_SIZE(cmd));
 
 	if (info->arg_from_user) {
 		ret = info->arg_from_user(karg, arg, cmd);
@@ -560,6 +708,16 @@  static void media_device_release(struct media_devnode *devnode)
 	dev_dbg(devnode->parent, "Media device released\n");
 }
 
+static void init_prop_list(struct media_device *mdev, struct list_head *list)
+{
+	struct media_prop *prop;
+
+	list_for_each_entry(prop, list, list) {
+		media_gobj_create(mdev, MEDIA_GRAPH_PROP, &prop->graph_obj);
+		init_prop_list(mdev, &prop->props);
+	}
+}
+
 /**
  * media_device_register_entity - Register an entity with a media device
  * @mdev:	The media device
@@ -581,9 +739,8 @@  int __must_check media_device_register_entity(struct media_device *mdev,
 	/* Warn if we apparently re-register an entity */
 	WARN_ON(entity->graph_obj.mdev != NULL);
 	entity->graph_obj.mdev = mdev;
-	INIT_LIST_HEAD(&entity->links);
-	entity->num_links = 0;
-	entity->num_backlinks = 0;
+	if (!entity->inited)
+		media_entity_init(entity);
 
 	ret = ida_alloc_min(&mdev->entity_internal_idx, 1, GFP_KERNEL);
 	if (ret < 0)
@@ -597,10 +754,17 @@  int __must_check media_device_register_entity(struct media_device *mdev,
 	/* Initialize media_gobj embedded at the entity */
 	media_gobj_create(mdev, MEDIA_GRAPH_ENTITY, &entity->graph_obj);
 
+	/* Initialize objects at the props */
+	init_prop_list(mdev, &entity->props);
+
 	/* Initialize objects at the pads */
-	for (i = 0; i < entity->num_pads; i++)
+	for (i = 0; i < entity->num_pads; i++) {
 		media_gobj_create(mdev, MEDIA_GRAPH_PAD,
-			       &entity->pads[i].graph_obj);
+				  &entity->pads[i].graph_obj);
+
+		/* Initialize objects at the pad props */
+		init_prop_list(mdev, &entity->pads[i].props);
+	}
 
 	/* invoke entity_notify callbacks */
 	list_for_each_entry_safe(notify, next, &mdev->entity_notify, list)
@@ -629,6 +793,18 @@  int __must_check media_device_register_entity(struct media_device *mdev,
 }
 EXPORT_SYMBOL_GPL(media_device_register_entity);
 
+static void media_device_free_props(struct list_head *list)
+{
+	while (!list_empty(list)) {
+		struct media_prop *prop;
+
+		prop = list_first_entry(list, struct media_prop, list);
+		list_del(&prop->list);
+		media_gobj_destroy(&prop->graph_obj);
+		kfree(prop);
+	}
+}
+
 static void __media_device_unregister_entity(struct media_entity *entity)
 {
 	struct media_device *mdev = entity->graph_obj.mdev;
@@ -650,8 +826,13 @@  static void __media_device_unregister_entity(struct media_entity *entity)
 	__media_entity_remove_links(entity);
 
 	/* Remove all pads that belong to this entity */
-	for (i = 0; i < entity->num_pads; i++)
+	for (i = 0; i < entity->num_pads; i++) {
+		media_device_free_props(&entity->pads[i].props);
 		media_gobj_destroy(&entity->pads[i].graph_obj);
+	}
+
+	/* Remove all props that belong to this entity */
+	media_device_free_props(&entity->props);
 
 	/* Remove the entity */
 	media_gobj_destroy(&entity->graph_obj);
@@ -690,6 +871,7 @@  void media_device_init(struct media_device *mdev)
 	INIT_LIST_HEAD(&mdev->interfaces);
 	INIT_LIST_HEAD(&mdev->pads);
 	INIT_LIST_HEAD(&mdev->links);
+	INIT_LIST_HEAD(&mdev->props);
 	INIT_LIST_HEAD(&mdev->entity_notify);
 	mutex_init(&mdev->graph_mutex);
 	ida_init(&mdev->entity_internal_idx);
diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c
index 0b1cb3559140..dfd0073eae31 100644
--- a/drivers/media/media-entity.c
+++ b/drivers/media/media-entity.c
@@ -34,6 +34,8 @@  static inline const char *gobj_type(enum media_gobj_type type)
 		return "link";
 	case MEDIA_GRAPH_INTF_DEVNODE:
 		return "intf-devnode";
+	case MEDIA_GRAPH_PROP:
+		return "prop";
 	default:
 		return "unknown";
 	}
@@ -106,7 +108,7 @@  static void dev_dbg_obj(const char *event_name,  struct media_gobj *gobj)
 	switch (media_type(gobj)) {
 	case MEDIA_GRAPH_ENTITY:
 		dev_dbg(gobj->mdev->dev,
-			"%s id %u: entity '%s'\n",
+			"%s id 0x%08x: entity '%s'\n",
 			event_name, media_id(gobj),
 			gobj_to_entity(gobj)->name);
 		break;
@@ -115,7 +117,7 @@  static void dev_dbg_obj(const char *event_name,  struct media_gobj *gobj)
 		struct media_link *link = gobj_to_link(gobj);
 
 		dev_dbg(gobj->mdev->dev,
-			"%s id %u: %s link id %u ==> id %u\n",
+			"%s id 0x%08x: %s link id 0x%08x ==> id 0x%08x\n",
 			event_name, media_id(gobj),
 			media_type(link->gobj0) == MEDIA_GRAPH_PAD ?
 				"data" : "interface",
@@ -128,7 +130,7 @@  static void dev_dbg_obj(const char *event_name,  struct media_gobj *gobj)
 		struct media_pad *pad = gobj_to_pad(gobj);
 
 		dev_dbg(gobj->mdev->dev,
-			"%s id %u: %s%spad '%s':%d\n",
+			"%s id 0x%08x: %s%spad '%s':%d\n",
 			event_name, media_id(gobj),
 			pad->flags & MEDIA_PAD_FL_SINK   ? "sink " : "",
 			pad->flags & MEDIA_PAD_FL_SOURCE ? "source " : "",
@@ -141,12 +143,22 @@  static void dev_dbg_obj(const char *event_name,  struct media_gobj *gobj)
 		struct media_intf_devnode *devnode = intf_to_devnode(intf);
 
 		dev_dbg(gobj->mdev->dev,
-			"%s id %u: intf_devnode %s - major: %d, minor: %d\n",
+			"%s id 0x%08x: intf_devnode %s - major: %d, minor: %d\n",
 			event_name, media_id(gobj),
 			intf_type(intf),
 			devnode->major, devnode->minor);
 		break;
 	}
+	case MEDIA_GRAPH_PROP:
+	{
+		struct media_prop *prop = gobj_to_prop(gobj);
+
+		dev_dbg(gobj->mdev->dev,
+			"%s id 0x%08x: prop '%s':0x%08x\n",
+			event_name, media_id(gobj),
+			prop->name, media_id(prop->owner));
+		break;
+	}
 	}
 #endif
 }
@@ -175,6 +187,9 @@  void media_gobj_create(struct media_device *mdev,
 	case MEDIA_GRAPH_INTF_DEVNODE:
 		list_add_tail(&gobj->list, &mdev->interfaces);
 		break;
+	case MEDIA_GRAPH_PROP:
+		list_add_tail(&gobj->list, &mdev->props);
+		break;
 	}
 
 	mdev->topology_version++;
@@ -212,6 +227,8 @@  int media_entity_pads_init(struct media_entity *entity, u16 num_pads,
 	if (num_pads >= MEDIA_ENTITY_MAX_PADS)
 		return -E2BIG;
 
+	if (!entity->inited)
+		media_entity_init(entity);
 	entity->num_pads = num_pads;
 	entity->pads = pads;
 
@@ -221,6 +238,7 @@  int media_entity_pads_init(struct media_entity *entity, u16 num_pads,
 	for (i = 0; i < num_pads; i++) {
 		pads[i].entity = entity;
 		pads[i].index = i;
+		INIT_LIST_HEAD(&pads[i].props);
 		if (mdev)
 			media_gobj_create(mdev, MEDIA_GRAPH_PAD,
 					&entity->pads[i].graph_obj);
@@ -233,6 +251,66 @@  int media_entity_pads_init(struct media_entity *entity, u16 num_pads,
 }
 EXPORT_SYMBOL_GPL(media_entity_pads_init);
 
+static struct media_prop *media_create_prop(struct media_gobj *owner, u32 type,
+		const char *name, const void *ptr, u32 payload_size)
+{
+	struct media_prop *prop = kzalloc(sizeof(*prop) + payload_size,
+					  GFP_KERNEL);
+
+	if (!prop)
+		return ERR_PTR(-ENOMEM);
+	prop->type = type;
+	strscpy(prop->name, name, sizeof(prop->name));
+	if (owner->mdev)
+		media_gobj_create(owner->mdev, MEDIA_GRAPH_PROP,
+				  &prop->graph_obj);
+	prop->owner = owner;
+	prop->payload_size = payload_size;
+	if (payload_size && ptr)
+		memcpy(prop->payload, ptr, payload_size);
+	INIT_LIST_HEAD(&prop->props);
+	return prop;
+}
+
+struct media_prop *media_entity_add_prop(struct media_entity *ent, u32 type,
+		const char *name, const void *ptr, u32 payload_size)
+{
+	struct media_prop *prop;
+
+	if (!ent->inited)
+		media_entity_init(ent);
+	prop = media_create_prop(&ent->graph_obj, type,
+				 name, ptr, payload_size);
+	if (!IS_ERR(prop))
+		list_add_tail(&prop->list, &ent->props);
+	return prop;
+}
+EXPORT_SYMBOL_GPL(media_entity_add_prop);
+
+struct media_prop *media_pad_add_prop(struct media_pad *pad, u32 type,
+		const char *name, const void *ptr, u32 payload_size)
+{
+	struct media_prop *prop = media_create_prop(&pad->graph_obj, type,
+						name, ptr, payload_size);
+
+	if (!IS_ERR(prop))
+		list_add_tail(&prop->list, &pad->props);
+	return prop;
+}
+EXPORT_SYMBOL_GPL(media_pad_add_prop);
+
+struct media_prop *media_prop_add_prop(struct media_prop *prop, u32 type,
+		const char *name, const void *ptr, u32 payload_size)
+{
+	struct media_prop *subprop = media_create_prop(&prop->graph_obj, type,
+						name, ptr, payload_size);
+
+	if (!IS_ERR(subprop))
+		list_add_tail(&subprop->list, &prop->props);
+	return subprop;
+}
+EXPORT_SYMBOL_GPL(media_prop_add_prop);
+
 /* -----------------------------------------------------------------------------
  * Graph traversal
  */
@@ -618,14 +696,25 @@  EXPORT_SYMBOL_GPL(media_entity_put);
  * Links management
  */
 
-static struct media_link *media_add_link(struct list_head *head)
+static struct media_link *media_add_link(struct list_head *head,
+					 u16 pad, bool add_tail)
 {
-	struct media_link *link;
+	struct media_link *link, *tmp;
 
 	link = kzalloc(sizeof(*link), GFP_KERNEL);
 	if (link == NULL)
 		return NULL;
 
+	if (add_tail) {
+		list_add_tail(&link->list, head);
+		return link;
+	}
+	list_for_each_entry(tmp, head, list) {
+		if (tmp->source->index == pad) {
+			list_add(&link->list, &tmp->list);
+			return link;
+		}
+	}
 	list_add_tail(&link->list, head);
 
 	return link;
@@ -699,7 +788,7 @@  media_create_pad_link(struct media_entity *source, u16 source_pad,
 	BUG_ON(source_pad >= source->num_pads);
 	BUG_ON(sink_pad >= sink->num_pads);
 
-	link = media_add_link(&source->links);
+	link = media_add_link(&source->links, source_pad, false);
 	if (link == NULL)
 		return -ENOMEM;
 
@@ -714,7 +803,7 @@  media_create_pad_link(struct media_entity *source, u16 source_pad,
 	/* Create the backlink. Backlinks are used to help graph traversal and
 	 * are not reported to userspace.
 	 */
-	backlink = media_add_link(&sink->links);
+	backlink = media_add_link(&sink->links, 0, true);
 	if (backlink == NULL) {
 		__media_entity_remove_link(source, link);
 		return -ENOMEM;
@@ -998,7 +1087,7 @@  struct media_link *media_create_intf_link(struct media_entity *entity,
 {
 	struct media_link *link;
 
-	link = media_add_link(&intf->links);
+	link = media_add_link(&intf->links, 0, true);
 	if (link == NULL)
 		return NULL;
 
diff --git a/include/media/media-device.h b/include/media/media-device.h
index bcc6ec434f1f..a30a931df00b 100644
--- a/include/media/media-device.h
+++ b/include/media/media-device.h
@@ -78,6 +78,7 @@  struct media_device_ops {
  * @interfaces:	List of registered interfaces
  * @pads:	List of registered pads
  * @links:	List of registered links
+ * @props:	List of registered properties
  * @entity_notify: List of registered entity_notify callbacks
  * @graph_mutex: Protects access to struct media_device data
  * @pm_count_walk: Graph walk for power state walk. Access serialised using
@@ -144,6 +145,7 @@  struct media_device {
 	struct list_head interfaces;
 	struct list_head pads;
 	struct list_head links;
+	struct list_head props;
 
 	/* notify callback list invoked when a new entity is registered */
 	struct list_head entity_notify;
@@ -382,6 +384,10 @@  void media_device_unregister_entity_notify(struct media_device *mdev,
 #define media_device_for_each_link(link, mdev)			\
 	list_for_each_entry(link, &(mdev)->links, graph_obj.list)
 
+/* Iterate over all props. */
+#define media_device_for_each_prop(prop, mdev)			\
+	list_for_each_entry(prop, &(mdev)->props, graph_obj.list)
+
 /**
  * media_device_pci_init() - create and initialize a
  *	struct &media_device from a PCI device.
diff --git a/include/media/media-entity.h b/include/media/media-entity.h
index e5f6960d92f6..937b1bddeef9 100644
--- a/include/media/media-entity.h
+++ b/include/media/media-entity.h
@@ -21,6 +21,7 @@ 
 
 #include <linux/bitmap.h>
 #include <linux/bug.h>
+#include <linux/err.h>
 #include <linux/fwnode.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
@@ -36,12 +37,14 @@ 
  * @MEDIA_GRAPH_LINK:		Identify a media link
  * @MEDIA_GRAPH_INTF_DEVNODE:	Identify a media Kernel API interface via
  *				a device node
+ * @MEDIA_GRAPH_PROP:		Identify a media property
  */
 enum media_gobj_type {
 	MEDIA_GRAPH_ENTITY,
 	MEDIA_GRAPH_PAD,
 	MEDIA_GRAPH_LINK,
 	MEDIA_GRAPH_INTF_DEVNODE,
+	MEDIA_GRAPH_PROP,
 };
 
 #define MEDIA_BITS_PER_TYPE		8
@@ -65,6 +68,7 @@  enum media_gobj_type {
 struct media_gobj {
 	struct media_device	*mdev;
 	u32			id;
+	u16			topology_idx;
 	struct list_head	list;
 };
 
@@ -193,6 +197,7 @@  enum media_pad_signal_type {
  * @flags:	Pad flags, as defined in
  *		:ref:`include/uapi/linux/media.h <media_header>`
  *		(seek for ``MEDIA_PAD_FL_*``)
+ * @props:	The list pad properties
  */
 struct media_pad {
 	struct media_gobj graph_obj;	/* must be first field in struct */
@@ -200,6 +205,31 @@  struct media_pad {
 	u16 index;
 	enum media_pad_signal_type sig_type;
 	unsigned long flags;
+	struct list_head props;
+};
+
+/**
+ * struct media_prop - A media property graph object.
+ *
+ * @graph_obj:	Embedded structure containing the media object common data
+ * @list:	Linked list associated with the object that owns the link.
+ * @owner:	Graph object this property belongs to
+ * @index:	Property index for the owner property array, numbered from 0 to n
+ * @type:	Property type
+ * @payload_size: Property payload size (i.e. additional bytes beyond this struct)
+ * @props:	The list of sub-properties
+ * @name:	Property name
+ * @payload:	Property payload starts here
+ */
+struct media_prop {
+	struct media_gobj graph_obj;	/* must be first field in struct */
+	struct list_head list;
+	struct media_gobj *owner;
+	u32 type;
+	u32 payload_size;
+	struct list_head props;
+	char name[32];
+	u8 payload[];
 };
 
 /**
@@ -266,6 +296,7 @@  enum media_entity_type {
  * @flags:	Entity flags, as defined in
  *		:ref:`include/uapi/linux/media.h <media_header>`
  *		(seek for ``MEDIA_ENT_FL_*``)
+ * @inited:	This struct was initialized.
  * @num_pads:	Number of sink and source pads.
  * @num_links:	Total number of links, forward and back, enabled and disabled.
  * @num_backlinks: Number of backlinks
@@ -273,6 +304,7 @@  enum media_entity_type {
  *		re-used if entities are unregistered or registered again.
  * @pads:	Pads array with the size defined by @num_pads.
  * @links:	List of data links.
+ * @props:	List of entity properties.
  * @ops:	Entity operations.
  * @stream_count: Stream count for the entity.
  * @use_count:	Use count for the entity.
@@ -300,6 +332,7 @@  struct media_entity {
 	enum media_entity_type obj_type;
 	u32 function;
 	unsigned long flags;
+	bool inited;
 
 	u16 num_pads;
 	u16 num_links;
@@ -308,6 +341,7 @@  struct media_entity {
 
 	struct media_pad *pads;
 	struct list_head links;
+	struct list_head props;
 
 	const struct media_entity_operations *ops;
 
@@ -362,6 +396,20 @@  struct media_intf_devnode {
 	u32				minor;
 };
 
+/**
+ * media_entity_init() - initialize the media entity struct
+ *
+ * @entity:	pointer to &media_entity
+ */
+static inline void media_entity_init(struct media_entity *entity)
+{
+	INIT_LIST_HEAD(&entity->links);
+	INIT_LIST_HEAD(&entity->props);
+	entity->num_links = 0;
+	entity->num_backlinks = 0;
+	entity->inited = true;
+}
+
 /**
  * media_entity_id() - return the media entity graph object id
  *
@@ -595,6 +643,15 @@  static inline bool media_entity_enum_intersects(
 #define gobj_to_intf(gobj) \
 		container_of(gobj, struct media_interface, graph_obj)
 
+/**
+ * gobj_to_prop - returns the struct &media_prop pointer from the
+ *	@gobj contained on it.
+ *
+ * @gobj: Pointer to the struct &media_gobj graph object
+ */
+#define gobj_to_prop(gobj) \
+		container_of(gobj, struct media_prop, graph_obj)
+
 /**
  * intf_to_devnode - returns the struct media_intf_devnode pointer from the
  *	@intf contained on it.
@@ -775,6 +832,264 @@  int media_create_pad_links(const struct media_device *mdev,
 
 void __media_entity_remove_links(struct media_entity *entity);
 
+/**
+ * media_entity_add_prop() - Add property to entity
+ *
+ * @entity:	entity where to add the property
+ * @type:	property type
+ * @name:	property name
+ * @ptr:	property pointer to payload
+ * @payload_size: property payload size
+ *
+ * Returns the new property on success, or an error pointer on failure.
+ */
+struct media_prop *media_entity_add_prop(struct media_entity *ent, u32 type,
+		const char *name, const void *ptr, u32 payload_size);
+
+/**
+ * media_pad_add_prop() - Add property to pad
+ *
+ * @pad:	pad where to add the property
+ * @type:	property type
+ * @name:	property name
+ * @ptr:	property pointer to payload
+ * @payload_size: property payload size
+ *
+ * Returns the new property on success, or an error pointer on failure.
+ */
+struct media_prop *media_pad_add_prop(struct media_pad *pad, u32 type,
+		const char *name, const void *ptr, u32 payload_size);
+
+/**
+ * media_prop() - Add sub-property to property
+ *
+ * @prop:	property where to add the sub-property
+ * @type:	sub-property type
+ * @name:	sub-property name
+ * @ptr:	sub-property pointer to payload
+ * @payload_size: sub-property payload size
+ *
+ * Returns the new property on success, or an error pointer on failure.
+ */
+struct media_prop *media_prop_add_prop(struct media_prop *prop, u32 type,
+		const char *name, const void *ptr, u32 payload_size);
+
+/**
+ * media_entity_add_prop_group() - Add group property to entity
+ *
+ * @entity:	entity where to add the property
+ * @name:	property name
+ *
+ * Returns the new property on success, or an error pointer on failure.
+ */
+static inline struct media_prop *media_entity_add_prop_group(struct media_entity *entity,
+					      const char *name)
+{
+	return media_entity_add_prop(entity, MEDIA_PROP_TYPE_GROUP,
+				     name, NULL, 0);
+}
+
+/**
+ * media_entity_add_prop_u64() - Add u64 property to entity
+ *
+ * @entity:	entity where to add the property
+ * @name:	property name
+ * @val:	property value
+ *
+ * Returns 0 on success, or an error on failure.
+ */
+static inline int media_entity_add_prop_u64(struct media_entity *entity,
+					    const char *name, u64 val)
+{
+	struct media_prop *prop =
+		media_entity_add_prop(entity, MEDIA_PROP_TYPE_U64,
+				      name, &val, sizeof(val));
+
+	return PTR_ERR_OR_ZERO(prop);
+}
+
+/**
+ * media_entity_add_prop_s64() - Add s64 property to entity
+ *
+ * @entity:	entity where to add the property
+ * @name:	property name
+ * @val:	property value
+ *
+ * Returns 0 on success, or an error on failure.
+ */
+static inline int media_entity_add_prop_s64(struct media_entity *entity,
+					    const char *name, s64 val)
+{
+	struct media_prop *prop =
+		media_entity_add_prop(entity, MEDIA_PROP_TYPE_S64,
+				      name, &val, sizeof(val));
+
+	return PTR_ERR_OR_ZERO(prop);
+}
+
+/**
+ * media_entity_add_prop_string() - Add string property to entity
+ *
+ * @entity:	entity where to add the property
+ * @name:	property name
+ * @string:	property string value
+ *
+ * Returns 0 on success, or an error on failure.
+ */
+static inline int media_entity_add_prop_string(struct media_entity *entity,
+					const char *name, const char *string)
+{
+	struct media_prop *prop =
+		media_entity_add_prop(entity, MEDIA_PROP_TYPE_STRING,
+				      name, string, strlen(string) + 1);
+
+	return PTR_ERR_OR_ZERO(prop);
+}
+
+/**
+ * media_pad_add_prop_group() - Add group property to pad
+ *
+ * @pad:	pad where to add the property
+ * @name:	property name
+ *
+ * Returns the new property on success, or an error pointer on failure.
+ */
+static inline struct media_prop *media_pad_add_prop_group(struct media_pad *pad,
+					   const char *name)
+{
+	return media_pad_add_prop(pad, MEDIA_PROP_TYPE_GROUP,
+				  name, NULL, 0);
+}
+
+/**
+ * media_pad_add_prop_u64() - Add u64 property to pad
+ *
+ * @pad:	pad where to add the property
+ * @name:	property name
+ * @val:	property value
+ *
+ * Returns 0 on success, or an error on failure.
+ */
+static inline int media_pad_add_prop_u64(struct media_pad *pad,
+					 const char *name, u64 val)
+{
+	struct media_prop *prop =
+		media_pad_add_prop(pad, MEDIA_PROP_TYPE_U64,
+				   name, &val, sizeof(val));
+
+	return PTR_ERR_OR_ZERO(prop);
+}
+
+/**
+ * media_pad_add_prop_s64() - Add s64 property to pad
+ *
+ * @pad:	pad where to add the property
+ * @name:	property name
+ * @val:	property value
+ *
+ * Returns 0 on success, or an error on failure.
+ */
+static inline int media_pad_add_prop_s64(struct media_pad *pad,
+					 const char *name, s64 val)
+{
+	struct media_prop *prop =
+		media_pad_add_prop(pad, MEDIA_PROP_TYPE_S64,
+				   name, &val, sizeof(val));
+
+	return PTR_ERR_OR_ZERO(prop);
+}
+
+/**
+ * media_pad_add_prop_string() - Add string property to pad
+ *
+ * @pad:	pad where to add the property
+ * @name:	property name
+ * @string:	property string value
+ *
+ * Returns 0 on success, or an error on failure.
+ */
+static inline int media_pad_add_prop_string(struct media_pad *pad,
+					const char *name, const char *string)
+{
+	struct media_prop *prop =
+		media_pad_add_prop(pad, MEDIA_PROP_TYPE_STRING,
+				   name, string, strlen(string) + 1);
+
+	return PTR_ERR_OR_ZERO(prop);
+}
+
+/**
+ * media_prop_add_prop_group() - Add group sub-property to property
+ *
+ * @prop:	property where to add the sub-property
+ * @name:	sub-property name
+ *
+ * Returns the new property on success, or an error pointer on failure.
+ */
+static inline struct media_prop *media_prop_add_prop_group(struct media_prop *prop,
+					   const char *name)
+{
+	return media_prop_add_prop(prop, MEDIA_PROP_TYPE_GROUP,
+				  name, NULL, 0);
+}
+
+/**
+ * media_prop_add_prop_u64() - Add u64 property to property
+ *
+ * @prop:	property where to add the sub-property
+ * @name:	sub-property name
+ * @val:	sub-property value
+ *
+ * Returns 0 on success, or an error on failure.
+ */
+static inline int media_prop_add_prop_u64(struct media_prop *prop,
+					  const char *name, u64 val)
+{
+	struct media_prop *subprop =
+		media_prop_add_prop(prop, MEDIA_PROP_TYPE_U64,
+				    name, &val, sizeof(val));
+
+	return PTR_ERR_OR_ZERO(subprop);
+}
+
+/**
+ * media_prop_add_prop_s64() - Add s64 property to property
+ *
+ * @prop:	property where to add the sub-property
+ * @name:	sub-property name
+ * @val:	sub-property value
+ *
+ * Returns 0 on success, or an error on failure.
+ */
+static inline int media_prop_add_prop_s64(struct media_prop *prop,
+					  const char *name, s64 val)
+{
+	struct media_prop *subprop =
+		media_prop_add_prop(prop, MEDIA_PROP_TYPE_S64,
+				    name, &val, sizeof(val));
+
+	return PTR_ERR_OR_ZERO(subprop);
+}
+
+/**
+ * media_prop_add_prop_string() - Add string property to property
+ *
+ * @prop:	property where to add the sub-property
+ * @name:	sub-property name
+ * @string:	sub-property string value
+ *
+ * Returns 0 on success, or an error on failure.
+ */
+static inline int media_prop_add_prop_string(struct media_prop *prop,
+					     const char *name, const char *string)
+{
+	struct media_prop *subprop =
+		media_prop_add_prop(prop, MEDIA_PROP_TYPE_STRING,
+				    name, string, strlen(string) + 1);
+
+	return PTR_ERR_OR_ZERO(subprop);
+}
+
 /**
  * media_entity_remove_links() - remove all links associated with an entity
  *