1 files changed, 382 insertions, 0 deletions

diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c
new file mode 100644
index 000000000000..16b70b4412f7
--- /dev/null
+++ b/drivers/media/media-device.c
@@ -0,0 +1,382 @@
+/*
+ * Media device
+ *
+ * Copyright (C) 2010 Nokia Corporation
+ *
+ * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ *           Sakari Ailus <sakari.ailus@iki.fi>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+#include <linux/media.h>
+
+#include <media/media-device.h>
+#include <media/media-devnode.h>
+#include <media/media-entity.h>
+
+/* -----------------------------------------------------------------------------
+ * Userspace API
+ */
+
+static int media_device_open(struct file *filp)
+{
+        return 0;
+}
+
+static int media_device_close(struct file *filp)
+{
+        return 0;
+}
+
+static int media_device_get_info(struct media_device *dev,
+                                 struct media_device_info __user *__info)
+{
+        struct media_device_info info;
+
+        memset(&info, 0, sizeof(info));
+
+        strlcpy(info.driver, dev->dev->driver->name, sizeof(info.driver));
+        strlcpy(info.model, dev->model, sizeof(info.model));
+        strlcpy(info.serial, dev->serial, sizeof(info.serial));
+        strlcpy(info.bus_info, dev->bus_info, sizeof(info.bus_info));
+
+        info.media_version = MEDIA_API_VERSION;
+        info.hw_revision = dev->hw_revision;
+        info.driver_version = dev->driver_version;
+
+        return copy_to_user(__info, &info, sizeof(*__info));
+}
+
+static struct media_entity *find_entity(struct media_device *mdev, u32 id)
+{
+        struct media_entity *entity;
+        int next = id & MEDIA_ENT_ID_FLAG_NEXT;
+
+        id &= ~MEDIA_ENT_ID_FLAG_NEXT;
+
+        spin_lock(&mdev->lock);
+
+        media_device_for_each_entity(entity, mdev) {
+                if ((entity->id == id && !next) ||
+                    (entity->id > id && next)) {
+                        spin_unlock(&mdev->lock);
+                        return entity;
+                }
+        }
+
+        spin_unlock(&mdev->lock);
+
+        return NULL;
+}
+
+static long media_device_enum_entities(struct media_device *mdev,
+                                       struct media_entity_desc __user *uent)
+{
+        struct media_entity *ent;
+        struct media_entity_desc u_ent;
+
+        if (copy_from_user(&u_ent.id, &uent->id, sizeof(u_ent.id)))
+                return -EFAULT;
+
+        ent = find_entity(mdev, u_ent.id);
+
+        if (ent == NULL)
+                return -EINVAL;
+
+        u_ent.id = ent->id;
+        u_ent.name[0] = '\0';
+        if (ent->name)
+                strlcpy(u_ent.name, ent->name, sizeof(u_ent.name));
+        u_ent.type = ent->type;
+        u_ent.revision = ent->revision;
+        u_ent.flags = ent->flags;
+        u_ent.group_id = ent->group_id;
+        u_ent.pads = ent->num_pads;
+        u_ent.links = ent->num_links - ent->num_backlinks;
+        u_ent.v4l.major = ent->v4l.major;
+        u_ent.v4l.minor = ent->v4l.minor;
+        if (copy_to_user(uent, &u_ent, sizeof(u_ent)))
+                return -EFAULT;
+        return 0;
+}
+
+static void media_device_kpad_to_upad(const struct media_pad *kpad,
+                                      struct media_pad_desc *upad)
+{
+        upad->entity = kpad->entity->id;
+        upad->index = kpad->index;
+        upad->flags = kpad->flags;
+}
+
+static long media_device_enum_links(struct media_device *mdev,
+                                    struct media_links_enum __user *ulinks)
+{
+        struct media_entity *entity;
+        struct media_links_enum links;
+
+        if (copy_from_user(&links, ulinks, sizeof(links)))
+                return -EFAULT;
+
+        entity = find_entity(mdev, links.entity);
+        if (entity == NULL)
+                return -EINVAL;
+
+        if (links.pads) {
+                unsigned int p;
+
+                for (p = 0; p < entity->num_pads; p++) {
+                        struct media_pad_desc pad;
+                        media_device_kpad_to_upad(&entity->pads[p], &pad);
+                        if (copy_to_user(&links.pads[p], &pad, sizeof(pad)))
+                                return -EFAULT;
+                }
+        }
+
+        if (links.links) {
+                struct media_link_desc __user *ulink;
+                unsigned int l;
+
+                for (l = 0, ulink = links.links; l < entity->num_links; l++) {
+                        struct media_link_desc link;
+
+                        /* Ignore backlinks. */
+                        if (entity->links[l].source->entity != entity)
+                                continue;
+
+                        media_device_kpad_to_upad(entity->links[l].source,
+                                                  &link.source);
+                        media_device_kpad_to_upad(entity->links[l].sink,
+                                                  &link.sink);
+                        link.flags = entity->links[l].flags;
+                        if (copy_to_user(ulink, &link, sizeof(*ulink)))
+                                return -EFAULT;
+                        ulink++;
+                }
+        }
+        if (copy_to_user(ulinks, &links, sizeof(*ulinks)))
+                return -EFAULT;
+        return 0;
+}
+
+static long media_device_setup_link(struct media_device *mdev,
+                                    struct media_link_desc __user *_ulink)
+{
+        struct media_link *link = NULL;
+        struct media_link_desc ulink;
+        struct media_entity *source;
+        struct media_entity *sink;
+        int ret;
+
+        if (copy_from_user(&ulink, _ulink, sizeof(ulink)))
+                return -EFAULT;
+
+        /* Find the source and sink entities and link.
+         */
+        source = find_entity(mdev, ulink.source.entity);
+        sink = find_entity(mdev, ulink.sink.entity);
+
+        if (source == NULL || sink == NULL)
+                return -EINVAL;
+
+        if (ulink.source.index >= source->num_pads ||
+            ulink.sink.index >= sink->num_pads)
+                return -EINVAL;
+
+        link = media_entity_find_link(&source->pads[ulink.source.index],
+                                      &sink->pads[ulink.sink.index]);
+        if (link == NULL)
+                return -EINVAL;
+
+        /* Setup the link on both entities. */
+        ret = __media_entity_setup_link(link, ulink.flags);
+
+        if (copy_to_user(_ulink, &ulink, sizeof(ulink)))
+                return -EFAULT;
+
+        return ret;
+}
+
+static long media_device_ioctl(struct file *filp, unsigned int cmd,
+                               unsigned long arg)
+{
+        struct media_devnode *devnode = media_devnode_data(filp);
+        struct media_device *dev = to_media_device(devnode);
+        long ret;
+
+        switch (cmd) {
+        case MEDIA_IOC_DEVICE_INFO:
+                ret = media_device_get_info(dev,
+                                (struct media_device_info __user *)arg);
+                break;
+
+        case MEDIA_IOC_ENUM_ENTITIES:
+                ret = media_device_enum_entities(dev,
+                                (struct media_entity_desc __user *)arg);
+                break;
+
+        case MEDIA_IOC_ENUM_LINKS:
+                mutex_lock(&dev->graph_mutex);
+                ret = media_device_enum_links(dev,
+                                (struct media_links_enum __user *)arg);
+                mutex_unlock(&dev->graph_mutex);
+                break;
+
+        case MEDIA_IOC_SETUP_LINK:
+                mutex_lock(&dev->graph_mutex);
+                ret = media_device_setup_link(dev,
+                                (struct media_link_desc __user *)arg);
+                mutex_unlock(&dev->graph_mutex);
+                break;
+
+        default:
+                ret = -ENOIOCTLCMD;
+        }
+
+        return ret;
+}
+
+static const struct media_file_operations media_device_fops = {
+        .owner = THIS_MODULE,
+        .open = media_device_open,
+        .ioctl = media_device_ioctl,
+        .release = media_device_close,
+};
+
+/* -----------------------------------------------------------------------------
+ * sysfs
+ */
+
+static ssize_t show_model(struct device *cd,
+                          struct device_attribute *attr, char *buf)
+{
+        struct media_device *mdev = to_media_device(to_media_devnode(cd));
+
+        return sprintf(buf, "%.*s\n", (int)sizeof(mdev->model), mdev->model);
+}
+
+static DEVICE_ATTR(model, S_IRUGO, show_model, NULL);
+
+/* -----------------------------------------------------------------------------
+ * Registration/unregistration
+ */
+
+static void media_device_release(struct media_devnode *mdev)
+{
+}
+
+/**
+ * media_device_register - register a media device
+ * @mdev:       The media device
+ *
+ * The caller is responsible for initializing the media device before
+ * registration. The following fields must be set:
+ *
+ * - dev must point to the parent device
+ * - model must be filled with the device model name
+ */
+int __must_check media_device_register(struct media_device *mdev)
+{
+        int ret;
+
+        if (WARN_ON(mdev->dev == NULL || mdev->model[0] == 0))
+                return -EINVAL;
+
+        mdev->entity_id = 1;
+        INIT_LIST_HEAD(&mdev->entities);
+        spin_lock_init(&mdev->lock);
+        mutex_init(&mdev->graph_mutex);
+
+        /* Register the device node. */
+        mdev->devnode.fops = &media_device_fops;
+        mdev->devnode.parent = mdev->dev;
+        mdev->devnode.release = media_device_release;
+        ret = media_devnode_register(&mdev->devnode);
+        if (ret < 0)
+                return ret;
+
+        ret = device_create_file(&mdev->devnode.dev, &dev_attr_model);
+        if (ret < 0) {
+                media_devnode_unregister(&mdev->devnode);
+                return ret;
+        }
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(media_device_register);
+
+/**
+ * media_device_unregister - unregister a media device
+ * @mdev:       The media device
+ *
+ */
+void media_device_unregister(struct media_device *mdev)
+{
+        struct media_entity *entity;
+        struct media_entity *next;
+
+        list_for_each_entry_safe(entity, next, &mdev->entities, list)
+                media_device_unregister_entity(entity);
+
+        device_remove_file(&mdev->devnode.dev, &dev_attr_model);
+        media_devnode_unregister(&mdev->devnode);
+}
+EXPORT_SYMBOL_GPL(media_device_unregister);
+
+/**
+ * media_device_register_entity - Register an entity with a media device
+ * @mdev:       The media device
+ * @entity:     The entity
+ */
+int __must_check media_device_register_entity(struct media_device *mdev,
+                                              struct media_entity *entity)
+{
+        /* Warn if we apparently re-register an entity */
+        WARN_ON(entity->parent != NULL);
+        entity->parent = mdev;
+
+        spin_lock(&mdev->lock);
+        if (entity->id == 0)
+                entity->id = mdev->entity_id++;
+        else
+                mdev->entity_id = max(entity->id + 1, mdev->entity_id);
+        list_add_tail(&entity->list, &mdev->entities);
+        spin_unlock(&mdev->lock);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(media_device_register_entity);
+
+/**
+ * media_device_unregister_entity - Unregister an entity
+ * @entity:     The entity
+ *
+ * If the entity has never been registered this function will return
+ * immediately.
+ */
+void media_device_unregister_entity(struct media_entity *entity)
+{
+        struct media_device *mdev = entity->parent;
+
+        if (mdev == NULL)
+                return;
+
+        spin_lock(&mdev->lock);
+        list_del(&entity->list);
+        spin_unlock(&mdev->lock);
+        entity->parent = NULL;
+}
+EXPORT_SYMBOL_GPL(media_device_unregister_entity);