diff options
Diffstat (limited to 'drivers/media/video/v4l2-dev.c')
| -rw-r--r-- | drivers/media/video/v4l2-dev.c | 54 |
1 files changed, 37 insertions, 17 deletions
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c index 13f87c22e78..91228b3df07 100644 --- a/drivers/media/video/v4l2-dev.c +++ b/drivers/media/video/v4l2-dev.c @@ -198,6 +198,23 @@ static long v4l2_unlocked_ioctl(struct file *filp, 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_unregistered(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); @@ -250,6 +267,7 @@ static const struct file_operations v4l2_unlocked_fops = { .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 @@ -265,6 +283,7 @@ static const struct file_operations v4l2_fops = { .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 @@ -288,37 +307,38 @@ static const struct file_operations v4l2_fops = { */ static int get_index(struct video_device *vdev, int num) { - u32 used = 0; - const int max_index = sizeof(used) * 8 - 1; + /* This can be static since this function is called with the global + videodev_lock held. */ + static DECLARE_BITMAP(used, VIDEO_NUM_DEVICES); int i; - /* Currently a single v4l driver instance cannot create more than - 32 devices. - Increase to u64 or an array of u32 if more are needed. */ - if (num > max_index) { + if (num >= VIDEO_NUM_DEVICES) { printk(KERN_ERR "videodev: %s num is too large\n", __func__); return -EINVAL; } - /* Some drivers do not set the parent. In that case always return 0. */ + /* Some drivers do not set the parent. In that case always return + num or 0. */ if (vdev->parent == NULL) - return 0; + return num >= 0 ? num : 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) { - used |= 1 << video_device[i]->index; + set_bit(video_device[i]->index, used); } } if (num >= 0) { - if (used & (1 << num)) + if (test_bit(num, used)) return -ENFILE; return num; } - i = ffz(used); - return i > max_index ? -ENFILE : i; + i = find_first_zero_bit(used, VIDEO_NUM_DEVICES); + return i == VIDEO_NUM_DEVICES ? -ENFILE : i; } int video_register_device(struct video_device *vdev, int type, int nr) @@ -365,12 +385,11 @@ int video_register_device_index(struct video_device *vdev, int type, int nr, /* A minor value of -1 marks this video device as never having been registered */ - if (vdev) - vdev->minor = -1; + vdev->minor = -1; /* the release callback MUST be present */ - WARN_ON(!vdev || !vdev->release); - if (!vdev || !vdev->release) + WARN_ON(!vdev->release); + if (!vdev->release) return -EINVAL; /* Part 1: check device type */ @@ -395,7 +414,7 @@ int video_register_device_index(struct video_device *vdev, int type, int nr, vdev->vfl_type = type; vdev->cdev = NULL; - if (vdev->v4l2_dev) + if (vdev->v4l2_dev && vdev->v4l2_dev->dev) vdev->parent = vdev->v4l2_dev->dev; /* Part 2: find a free minor, kernel number and device index. */ @@ -582,6 +601,7 @@ 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); /* |