diff options
Diffstat (limited to 'drivers/media/video/v4l2-dev.c')
| -rw-r--r-- | drivers/media/video/v4l2-dev.c | 653 |
1 files changed, 0 insertions, 653 deletions
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c deleted file mode 100644 index 70906991606..00000000000 --- a/drivers/media/video/v4l2-dev.c +++ /dev/null @@ -1,653 +0,0 @@ -/* - * Video capture interface for Linux version 2 - * - * A generic video device interface for the LINUX operating system - * using a set of device structures/vectors for low level operations. - * - * 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. - * - * Authors: Alan Cox, <alan@lxorguk.ukuu.org.uk> (version 1) - * Mauro Carvalho Chehab <mchehab@infradead.org> (version 2) - * - * Fixes: 20000516 Claudio Matsuoka <claudio@conectiva.com> - * - Added procfs support - */ - -#include <linux/module.h> -#include <linux/types.h> -#include <linux/kernel.h> -#include <linux/mm.h> -#include <linux/string.h> -#include <linux/errno.h> -#include <linux/init.h> -#include <linux/kmod.h> -#include <linux/slab.h> -#include <asm/uaccess.h> -#include <asm/system.h> - -#include <media/v4l2-common.h> -#include <media/v4l2-device.h> -#include <media/v4l2-ioctl.h> - -#define VIDEO_NUM_DEVICES 256 -#define VIDEO_NAME "video4linux" - -/* - * sysfs stuff - */ - -static ssize_t show_index(struct device *cd, - struct device_attribute *attr, char *buf) -{ - struct video_device *vdev = to_video_device(cd); - - return sprintf(buf, "%i\n", vdev->index); -} - -static ssize_t show_name(struct device *cd, - struct device_attribute *attr, char *buf) -{ - struct video_device *vdev = to_video_device(cd); - - return sprintf(buf, "%.*s\n", (int)sizeof(vdev->name), vdev->name); -} - -static struct device_attribute video_device_attrs[] = { - __ATTR(name, S_IRUGO, show_name, NULL), - __ATTR(index, S_IRUGO, show_index, NULL), - __ATTR_NULL -}; - -/* - * Active devices - */ -static struct video_device *video_device[VIDEO_NUM_DEVICES]; -static DEFINE_MUTEX(videodev_lock); -static DECLARE_BITMAP(devnode_nums[VFL_TYPE_MAX], VIDEO_NUM_DEVICES); - -/* Device node utility functions */ - -/* Note: these utility functions all assume that vfl_type is in the range - [0, VFL_TYPE_MAX-1]. */ - -#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES -/* Return the bitmap corresponding to vfl_type. */ -static inline unsigned long *devnode_bits(int vfl_type) -{ - /* Any types not assigned to fixed minor ranges must be mapped to - one single bitmap for the purposes of finding a free node number - since all those unassigned types use the same minor range. */ - int idx = (vfl_type > VFL_TYPE_VTX) ? VFL_TYPE_MAX - 1 : vfl_type; - - return devnode_nums[idx]; -} -#else -/* Return the bitmap corresponding to vfl_type. */ -static inline unsigned long *devnode_bits(int vfl_type) -{ - return devnode_nums[vfl_type]; -} -#endif - -/* Mark device node number vdev->num as used */ -static inline void devnode_set(struct video_device *vdev) -{ - set_bit(vdev->num, devnode_bits(vdev->vfl_type)); -} - -/* Mark device node number vdev->num as unused */ -static inline void devnode_clear(struct video_device *vdev) -{ - clear_bit(vdev->num, devnode_bits(vdev->vfl_type)); -} - -/* Try to find a free device node number in the range [from, to> */ -static inline int devnode_find(struct video_device *vdev, int from, int to) -{ - return find_next_zero_bit(devnode_bits(vdev->vfl_type), to, from); -} - -struct video_device *video_device_alloc(void) -{ - return kzalloc(sizeof(struct video_device), GFP_KERNEL); -} -EXPORT_SYMBOL(video_device_alloc); - -void video_device_release(struct video_device *vdev) -{ - kfree(vdev); -} -EXPORT_SYMBOL(video_device_release); - -void video_device_release_empty(struct video_device *vdev) -{ - /* Do nothing */ - /* Only valid when the video_device struct is a static. */ -} -EXPORT_SYMBOL(video_device_release_empty); - -static inline void video_get(struct video_device *vdev) -{ - get_device(&vdev->dev); -} - -static inline void video_put(struct video_device *vdev) -{ - put_device(&vdev->dev); -} - -/* Called when the last user of the video device exits. */ -static void v4l2_device_release(struct device *cd) -{ - struct video_device *vdev = to_video_device(cd); - - mutex_lock(&videodev_lock); - if (video_device[vdev->minor] != vdev) { - mutex_unlock(&videodev_lock); - /* should not happen */ - WARN_ON(1); - return; - } - - /* Free up this device for reuse */ - video_device[vdev->minor] = NULL; - - /* Delete the cdev on this minor as well */ - cdev_del(vdev->cdev); - /* Just in case some driver tries to access this from - the release() callback. */ - vdev->cdev = NULL; - - /* Mark device node number as free */ - devnode_clear(vdev); - - mutex_unlock(&videodev_lock); - - /* Release video_device and perform other - cleanups as needed. */ - vdev->release(vdev); -} - -static struct class video_class = { - .name = VIDEO_NAME, - .dev_attrs = video_device_attrs, -}; - -struct video_device *video_devdata(struct file *file) -{ - return video_device[iminor(file->f_path.dentry->d_inode)]; -} -EXPORT_SYMBOL(video_devdata); - -static ssize_t v4l2_read(struct file *filp, char __user *buf, - size_t sz, loff_t *off) -{ - struct video_device *vdev = video_devdata(filp); - - if (!vdev->fops->read) - return -EINVAL; - if (!video_is_registered(vdev)) - return -EIO; - return vdev->fops->read(filp, buf, sz, off); -} - -static ssize_t v4l2_write(struct file *filp, const char __user *buf, - size_t sz, loff_t *off) -{ - struct video_device *vdev = video_devdata(filp); - - if (!vdev->fops->write) - return -EINVAL; - if (!video_is_registered(vdev)) - return -EIO; - return vdev->fops->write(filp, buf, sz, off); -} - -static unsigned int v4l2_poll(struct file *filp, struct poll_table_struct *poll) -{ - struct video_device *vdev = video_devdata(filp); - - if (!vdev->fops->poll || !video_is_registered(vdev)) - return DEFAULT_POLLMASK; - return vdev->fops->poll(filp, poll); -} - -static int v4l2_ioctl(struct inode *inode, struct file *filp, - unsigned int cmd, unsigned long arg) -{ - struct video_device *vdev = video_devdata(filp); - - if (!vdev->fops->ioctl) - return -ENOTTY; - /* Allow ioctl to continue even if the device was unregistered. - Things like dequeueing buffers might still be useful. */ - return vdev->fops->ioctl(filp, cmd, arg); -} - -static long v4l2_unlocked_ioctl(struct file *filp, - unsigned int cmd, unsigned long arg) -{ - struct video_device *vdev = video_devdata(filp); - - if (!vdev->fops->unlocked_ioctl) - return -ENOTTY; - /* Allow ioctl to continue even if the device was unregistered. - Things like dequeueing buffers might still be useful. */ - return vdev->fops->unlocked_ioctl(filp, cmd, arg); -} - -#ifdef CONFIG_MMU -#define v4l2_get_unmapped_area NULL -#else -static unsigned long v4l2_get_unmapped_area(struct file *filp, - unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags) -{ - struct video_device *vdev = video_devdata(filp); - - if (!vdev->fops->get_unmapped_area) - return -ENOSYS; - if (!video_is_registered(vdev)) - return -ENODEV; - return vdev->fops->get_unmapped_area(filp, addr, len, pgoff, flags); -} -#endif - -static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm) -{ - struct video_device *vdev = video_devdata(filp); - - if (!vdev->fops->mmap || !video_is_registered(vdev)) - return -ENODEV; - return vdev->fops->mmap(filp, vm); -} - -/* Override for the open function */ -static int v4l2_open(struct inode *inode, struct file *filp) -{ - struct video_device *vdev; - int ret = 0; - - /* Check if the video device is available */ - mutex_lock(&videodev_lock); - vdev = video_devdata(filp); - /* return ENODEV if the video device has been removed - already or if it is not registered anymore. */ - if (vdev == NULL || !video_is_registered(vdev)) { - mutex_unlock(&videodev_lock); - return -ENODEV; - } - /* and increase the device refcount */ - video_get(vdev); - mutex_unlock(&videodev_lock); - if (vdev->fops->open) - ret = vdev->fops->open(filp); - - /* decrease the refcount in case of an error */ - if (ret) - video_put(vdev); - return ret; -} - -/* Override for the release function */ -static int v4l2_release(struct inode *inode, struct file *filp) -{ - struct video_device *vdev = video_devdata(filp); - int ret = 0; - - if (vdev->fops->release) - vdev->fops->release(filp); - - /* decrease the refcount unconditionally since the release() - return value is ignored. */ - video_put(vdev); - return ret; -} - -static const struct file_operations v4l2_unlocked_fops = { - .owner = THIS_MODULE, - .read = v4l2_read, - .write = v4l2_write, - .open = v4l2_open, - .get_unmapped_area = v4l2_get_unmapped_area, - .mmap = v4l2_mmap, - .unlocked_ioctl = v4l2_unlocked_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = v4l2_compat_ioctl32, -#endif - .release = v4l2_release, - .poll = v4l2_poll, - .llseek = no_llseek, -}; - -static const struct file_operations v4l2_fops = { - .owner = THIS_MODULE, - .read = v4l2_read, - .write = v4l2_write, - .open = v4l2_open, - .get_unmapped_area = v4l2_get_unmapped_area, - .mmap = v4l2_mmap, - .ioctl = v4l2_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = v4l2_compat_ioctl32, -#endif - .release = v4l2_release, - .poll = v4l2_poll, - .llseek = no_llseek, -}; - -/** - * get_index - assign stream index number based on parent device - * @vdev: video_device to assign index number to, vdev->parent should be assigned - * - * Note that when this is called the new device has not yet been registered - * in the video_device array, but it was able to obtain a minor number. - * - * This means that we can always obtain a free stream index number since - * the worst case scenario is that there are VIDEO_NUM_DEVICES - 1 slots in - * use of the video_device array. - * - * Returns a free index number. - */ -static int get_index(struct video_device *vdev) -{ - /* This can be static since this function is called with the global - videodev_lock held. */ - static DECLARE_BITMAP(used, VIDEO_NUM_DEVICES); - int i; - - /* Some drivers do not set the parent. In that case always return 0. */ - if (vdev->parent == NULL) - return 0; - - bitmap_zero(used, VIDEO_NUM_DEVICES); - - for (i = 0; i < VIDEO_NUM_DEVICES; i++) { - if (video_device[i] != NULL && - video_device[i]->parent == vdev->parent) { - set_bit(video_device[i]->index, used); - } - } - - return find_first_zero_bit(used, VIDEO_NUM_DEVICES); -} - -/** - * video_register_device - register video4linux devices - * @vdev: video device structure we want to register - * @type: type of device to register - * @nr: which device node number (0 == /dev/video0, 1 == /dev/video1, ... - * -1 == first free) - * @warn_if_nr_in_use: warn if the desired device node number - * was already in use and another number was chosen instead. - * - * The registration code assigns minor numbers and device node numbers - * based on the requested type and registers the new device node with - * the kernel. - * An error is returned if no free minor or device node number could be - * found, or if the registration of the device node failed. - * - * Zero is returned on success. - * - * Valid types are - * - * %VFL_TYPE_GRABBER - A frame grabber - * - * %VFL_TYPE_VTX - A teletext device - * - * %VFL_TYPE_VBI - Vertical blank data (undecoded) - * - * %VFL_TYPE_RADIO - A radio card - */ -static int __video_register_device(struct video_device *vdev, int type, int nr, - int warn_if_nr_in_use) -{ - int i = 0; - int ret; - int minor_offset = 0; - int minor_cnt = VIDEO_NUM_DEVICES; - const char *name_base; - void *priv = video_get_drvdata(vdev); - - /* A minor value of -1 marks this video device as never - having been registered */ - vdev->minor = -1; - - /* the release callback MUST be present */ - WARN_ON(!vdev->release); - if (!vdev->release) - return -EINVAL; - - /* Part 1: check device type */ - switch (type) { - case VFL_TYPE_GRABBER: - name_base = "video"; - break; - case VFL_TYPE_VTX: - name_base = "vtx"; - break; - case VFL_TYPE_VBI: - name_base = "vbi"; - break; - case VFL_TYPE_RADIO: - name_base = "radio"; - break; - default: - printk(KERN_ERR "%s called with unknown type: %d\n", - __func__, type); - return -EINVAL; - } - - vdev->vfl_type = type; - vdev->cdev = NULL; - if (vdev->v4l2_dev && vdev->v4l2_dev->dev) - vdev->parent = vdev->v4l2_dev->dev; - - /* Part 2: find a free minor, device node number and device index. */ -#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES - /* Keep the ranges for the first four types for historical - * reasons. - * Newer devices (not yet in place) should use the range - * of 128-191 and just pick the first free minor there - * (new style). */ - switch (type) { - case VFL_TYPE_GRABBER: - minor_offset = 0; - minor_cnt = 64; - break; - case VFL_TYPE_RADIO: - minor_offset = 64; - minor_cnt = 64; - break; - case VFL_TYPE_VTX: - minor_offset = 192; - minor_cnt = 32; - break; - case VFL_TYPE_VBI: - minor_offset = 224; - minor_cnt = 32; - break; - default: - minor_offset = 128; - minor_cnt = 64; - break; - } -#endif - - /* Pick a device node number */ - mutex_lock(&videodev_lock); - nr = devnode_find(vdev, nr == -1 ? 0 : nr, minor_cnt); - if (nr == minor_cnt) - nr = devnode_find(vdev, 0, minor_cnt); - if (nr == minor_cnt) { - printk(KERN_ERR "could not get a free device node number\n"); - mutex_unlock(&videodev_lock); - return -ENFILE; - } -#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES - /* 1-on-1 mapping of device node number to minor number */ - i = nr; -#else - /* The device node number and minor numbers are independent, so - we just find the first free minor number. */ - for (i = 0; i < VIDEO_NUM_DEVICES; i++) - if (video_device[i] == NULL) - break; - if (i == VIDEO_NUM_DEVICES) { - mutex_unlock(&videodev_lock); - printk(KERN_ERR "could not get a free minor\n"); - return -ENFILE; - } -#endif - vdev->minor = i + minor_offset; - vdev->num = nr; - devnode_set(vdev); - - /* Should not happen since we thought this minor was free */ - WARN_ON(video_device[vdev->minor] != NULL); - vdev->index = get_index(vdev); - mutex_unlock(&videodev_lock); - - /* Part 3: Initialize the character device */ - vdev->cdev = cdev_alloc(); - if (vdev->cdev == NULL) { - ret = -ENOMEM; - goto cleanup; - } - if (vdev->fops->unlocked_ioctl) - vdev->cdev->ops = &v4l2_unlocked_fops; - else - vdev->cdev->ops = &v4l2_fops; - vdev->cdev->owner = vdev->fops->owner; - ret = cdev_add(vdev->cdev, MKDEV(VIDEO_MAJOR, vdev->minor), 1); - if (ret < 0) { - printk(KERN_ERR "%s: cdev_add failed\n", __func__); - kfree(vdev->cdev); - vdev->cdev = NULL; - goto cleanup; - } - - /* Part 4: register the device with sysfs */ - memset(&vdev->dev, 0, sizeof(vdev->dev)); - /* The memset above cleared the device's drvdata, so - put back the copy we made earlier. */ - video_set_drvdata(vdev, priv); - vdev->dev.class = &video_class; - vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor); - if (vdev->parent) - vdev->dev.parent = vdev->parent; - dev_set_name(&vdev->dev, "%s%d", name_base, vdev->num); - ret = device_register(&vdev->dev); - if (ret < 0) { - printk(KERN_ERR "%s: device_register failed\n", __func__); - goto cleanup; - } - /* Register the release callback that will be called when the last - reference to the device goes away. */ - vdev->dev.release = v4l2_device_release; - - if (nr != -1 && nr != vdev->num && warn_if_nr_in_use) - printk(KERN_WARNING "%s: requested %s%d, got %s\n", __func__, - name_base, nr, video_device_node_name(vdev)); - - /* Part 5: Activate this minor. The char device can now be used. */ - set_bit(V4L2_FL_REGISTERED, &vdev->flags); - mutex_lock(&videodev_lock); - video_device[vdev->minor] = vdev; - mutex_unlock(&videodev_lock); - return 0; - -cleanup: - mutex_lock(&videodev_lock); - if (vdev->cdev) - cdev_del(vdev->cdev); - devnode_clear(vdev); - mutex_unlock(&videodev_lock); - /* Mark this video device as never having been registered. */ - vdev->minor = -1; - return ret; -} - -int video_register_device(struct video_device *vdev, int type, int nr) -{ - return __video_register_device(vdev, type, nr, 1); -} -EXPORT_SYMBOL(video_register_device); - -int video_register_device_no_warn(struct video_device *vdev, int type, int nr) -{ - return __video_register_device(vdev, type, nr, 0); -} -EXPORT_SYMBOL(video_register_device_no_warn); - -/** - * video_unregister_device - unregister a video4linux device - * @vdev: the device to unregister - * - * This unregisters the passed device. Future open calls will - * be met with errors. - */ -void video_unregister_device(struct video_device *vdev) -{ - /* Check if vdev was ever registered at all */ - if (!vdev || !video_is_registered(vdev)) - return; - - mutex_lock(&videodev_lock); - clear_bit(V4L2_FL_REGISTERED, &vdev->flags); - mutex_unlock(&videodev_lock); - device_unregister(&vdev->dev); -} -EXPORT_SYMBOL(video_unregister_device); - -/* - * Initialise video for linux - */ -static int __init videodev_init(void) -{ - dev_t dev = MKDEV(VIDEO_MAJOR, 0); - int ret; - - printk(KERN_INFO "Linux video capture interface: v2.00\n"); - ret = register_chrdev_region(dev, VIDEO_NUM_DEVICES, VIDEO_NAME); - if (ret < 0) { - printk(KERN_WARNING "videodev: unable to get major %d\n", - VIDEO_MAJOR); - return ret; - } - - ret = class_register(&video_class); - if (ret < 0) { - unregister_chrdev_region(dev, VIDEO_NUM_DEVICES); - printk(KERN_WARNING "video_dev: class_register failed\n"); - return -EIO; - } - - return 0; -} - -static void __exit videodev_exit(void) -{ - dev_t dev = MKDEV(VIDEO_MAJOR, 0); - - class_unregister(&video_class); - unregister_chrdev_region(dev, VIDEO_NUM_DEVICES); -} - -module_init(videodev_init) -module_exit(videodev_exit) - -MODULE_AUTHOR("Alan Cox, Mauro Carvalho Chehab <mchehab@infradead.org>"); -MODULE_DESCRIPTION("Device registrar for Video4Linux drivers v2"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS_CHARDEV_MAJOR(VIDEO_MAJOR); - - -/* - * Local variables: - * c-basic-offset: 8 - * End: - */ |