linux/drivers/media/media-device.c
Paul Gortmaker 35a246363e drivers/media: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required
These two macros were in module.h but now module.h is no longer
sprayed across every source file imaginable, so the users need
to expicitly call out their use of them.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:51 -04:00

383 lines
9.5 KiB
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;
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);