https://github.com/torvalds/linux
Tip revision: dcd6c92267155e70a94b3927bce681ce74b80d1f authored by Linus Torvalds on 19 January 2012, 23:04:48 UTC
Linux 3.3-rc1
Linux 3.3-rc1
Tip revision: dcd6c92
media-device.c
/*
* 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 <linux/export.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;
memcpy(&u_ent.raw, &ent->info, sizeof(ent->info));
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);