1 files changed, 150 insertions, 150 deletions

diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
index 155fdec9ac7d..ccd6566a515e 100644
--- a/drivers/media/video/v4l2-dev.c
+++ b/drivers/media/video/v4l2-dev.c
@@ -42,6 +42,7 @@ static ssize_t show_index(struct device *cd,
                          struct device_attribute *attr, char *buf)
 {
         struct video_device *vfd = container_of(cd, struct video_device, dev);
+
         return sprintf(buf, "%i\n", vfd->index);
 }
 
@@ -49,6 +50,7 @@ static ssize_t show_name(struct device *cd,
                          struct device_attribute *attr, char *buf)
 {
         struct video_device *vfd = container_of(cd, struct video_device, dev);
+
         return sprintf(buf, "%.*s\n", (int)sizeof(vfd->name), vfd->name);
 }
 
@@ -58,12 +60,16 @@ static struct device_attribute video_device_attrs[] = {
         __ATTR_NULL
 };
 
+/*
+ *      Active devices
+ */
+static struct video_device *video_device[VIDEO_NUM_DEVICES];
+static DEFINE_MUTEX(videodev_lock);
+static DECLARE_BITMAP(video_nums[VFL_TYPE_MAX], VIDEO_NUM_DEVICES);
+
 struct video_device *video_device_alloc(void)
 {
-        struct video_device *vfd;
-
-        vfd = kzalloc(sizeof(*vfd), GFP_KERNEL);
-        return vfd;
+        return kzalloc(sizeof(struct video_device), GFP_KERNEL);
 }
 EXPORT_SYMBOL(video_device_alloc);
 
@@ -73,16 +79,52 @@ void video_device_release(struct video_device *vfd)
 }
 EXPORT_SYMBOL(video_device_release);
 
+void video_device_release_empty(struct video_device *vfd)
+{
+        /* Do nothing */
+        /* Only valid when the video_device struct is a static. */
+}
+EXPORT_SYMBOL(video_device_release_empty);
+
+/* Called when the last user of the character device is gone. */
+static void v4l2_chardev_release(struct kobject *kobj)
+{
+        struct video_device *vfd = container_of(kobj, struct video_device, cdev.kobj);
+
+        mutex_lock(&videodev_lock);
+        if (video_device[vfd->minor] != vfd) {
+                mutex_unlock(&videodev_lock);
+                BUG();
+                return;
+        }
+
+        /* Free up this device for reuse */
+        video_device[vfd->minor] = NULL;
+        clear_bit(vfd->num, video_nums[vfd->vfl_type]);
+        mutex_unlock(&videodev_lock);
+
+        /* Release the character device */
+        vfd->cdev_release(kobj);
+        /* Release video_device and perform other
+           cleanups as needed. */
+        if (vfd->release)
+                vfd->release(vfd);
+}
+
+/* The new kobj_type for the character device */
+static struct kobj_type v4l2_ktype_cdev_default = {
+        .release = v4l2_chardev_release,
+};
+
 static void video_release(struct device *cd)
 {
         struct video_device *vfd = container_of(cd, struct video_device, dev);
 
-#if 1
-        /* needed until all drivers are fixed */
-        if (!vfd->release)
-                return;
-#endif
-        vfd->release(vfd);
+        /* It's now safe to delete the char device.
+           This will either trigger the v4l2_chardev_release immediately (if
+           the refcount goes to 0) or later when the last user of the
+           character device closes it. */
+        cdev_del(&vfd->cdev);
 }
 
 static struct class video_class = {
@@ -91,87 +133,12 @@ static struct class video_class = {
         .dev_release = video_release,
 };
 
-/*
- *      Active devices
- */
-
-static struct video_device *video_device[VIDEO_NUM_DEVICES];
-static DEFINE_MUTEX(videodev_lock);
-
 struct video_device *video_devdata(struct file *file)
 {
         return video_device[iminor(file->f_path.dentry->d_inode)];
 }
 EXPORT_SYMBOL(video_devdata);
 
-/*
- *      Open a video device - FIXME: Obsoleted
- */
-static int video_open(struct inode *inode, struct file *file)
-{
-        unsigned int minor = iminor(inode);
-        int err = 0;
-        struct video_device *vfl;
-        const struct file_operations *old_fops;
-
-        if (minor >= VIDEO_NUM_DEVICES)
-                return -ENODEV;
-        lock_kernel();
-        mutex_lock(&videodev_lock);
-        vfl = video_device[minor];
-        if (vfl == NULL) {
-                mutex_unlock(&videodev_lock);
-                request_module("char-major-%d-%d", VIDEO_MAJOR, minor);
-                mutex_lock(&videodev_lock);
-                vfl = video_device[minor];
-                if (vfl == NULL) {
-                        mutex_unlock(&videodev_lock);
-                        unlock_kernel();
-                        return -ENODEV;
-                }
-        }
-        old_fops = file->f_op;
-        file->f_op = fops_get(vfl->fops);
-        if (file->f_op->open)
-                err = file->f_op->open(inode, file);
-        if (err) {
-                fops_put(file->f_op);
-                file->f_op = fops_get(old_fops);
-        }
-        fops_put(old_fops);
-        mutex_unlock(&videodev_lock);
-        unlock_kernel();
-        return err;
-}
-
-/*
- * open/release helper functions -- handle exclusive opens
- * Should be removed soon
- */
-int video_exclusive_open(struct inode *inode, struct file *file)
-{
-        struct video_device *vfl = video_devdata(file);
-        int retval = 0;
-
-        mutex_lock(&vfl->lock);
-        if (vfl->users)
-                retval = -EBUSY;
-        else
-                vfl->users++;
-        mutex_unlock(&vfl->lock);
-        return retval;
-}
-EXPORT_SYMBOL(video_exclusive_open);
-
-int video_exclusive_release(struct inode *inode, struct file *file)
-{
-        struct video_device *vfl = video_devdata(file);
-
-        vfl->users--;
-        return 0;
-}
-EXPORT_SYMBOL(video_exclusive_release);
-
 /**
  * get_index - assign stream number based on parent device
  * @vdev: video_device to assign index number to, vdev->dev should be assigned
@@ -252,33 +219,29 @@ int video_register_device_index(struct video_device *vfd, int type, int nr,
                                         int index)
 {
         int i = 0;
-        int base;
-        int end;
         int ret;
-        char *name_base;
+        int minor_offset = 0;
+        int minor_cnt = VIDEO_NUM_DEVICES;
+        const char *name_base;
+        void *priv = video_get_drvdata(vfd);
+
+        /* the release callback MUST be present */
+        BUG_ON(!vfd->release);
 
         if (vfd == NULL)
                 return -EINVAL;
 
         switch (type) {
         case VFL_TYPE_GRABBER:
-                base = MINOR_VFL_TYPE_GRABBER_MIN;
-                end = MINOR_VFL_TYPE_GRABBER_MAX+1;
                 name_base = "video";
                 break;
         case VFL_TYPE_VTX:
-                base = MINOR_VFL_TYPE_VTX_MIN;
-                end = MINOR_VFL_TYPE_VTX_MAX+1;
                 name_base = "vtx";
                 break;
         case VFL_TYPE_VBI:
-                base = MINOR_VFL_TYPE_VBI_MIN;
-                end = MINOR_VFL_TYPE_VBI_MAX+1;
                 name_base = "vbi";
                 break;
         case VFL_TYPE_RADIO:
-                base = MINOR_VFL_TYPE_RADIO_MIN;
-                end = MINOR_VFL_TYPE_RADIO_MAX+1;
                 name_base = "radio";
                 break;
         default:
@@ -287,28 +250,70 @@ int video_register_device_index(struct video_device *vfd, int type, int nr,
                 return -EINVAL;
         }
 
+        vfd->vfl_type = type;
+
+#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
+
+        /* Initialize the character device */
+        cdev_init(&vfd->cdev, vfd->fops);
+        vfd->cdev.owner = vfd->fops->owner;
         /* pick a minor number */
         mutex_lock(&videodev_lock);
-        if (nr >= 0  &&  nr < end-base) {
-                /* use the one the driver asked for */
-                i = base + nr;
-                if (NULL != video_device[i]) {
-                        mutex_unlock(&videodev_lock);
-                        return -ENFILE;
-                }
-        } else {
-                /* use first free */
-                for (i = base; i < end; i++)
-                        if (NULL == video_device[i])
-                                break;
-                if (i == end) {
-                        mutex_unlock(&videodev_lock);
-                        return -ENFILE;
-                }
+        nr = find_next_zero_bit(video_nums[type], minor_cnt, nr == -1 ? 0 : nr);
+        if (nr == minor_cnt)
+                nr = find_first_zero_bit(video_nums[type], minor_cnt);
+        if (nr == minor_cnt) {
+                printk(KERN_ERR "could not get a free kernel number\n");
+                mutex_unlock(&videodev_lock);
+                return -ENFILE;
         }
-        video_device[i] = vfd;
-        vfd->vfl_type = type;
-        vfd->minor = i;
+#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
+        /* 1-on-1 mapping of kernel number to minor number */
+        i = nr;
+#else
+        /* The kernel number and minor numbers are independent */
+        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
+        vfd->minor = i + minor_offset;
+        vfd->num = nr;
+        set_bit(nr, video_nums[type]);
+        BUG_ON(video_device[vfd->minor]);
+        video_device[vfd->minor] = vfd;
 
         ret = get_index(vfd, index);
         vfd->index = ret;
@@ -320,35 +325,41 @@ int video_register_device_index(struct video_device *vfd, int type, int nr,
                 goto fail_minor;
         }
 
-        mutex_init(&vfd->lock);
-
+        ret = cdev_add(&vfd->cdev, MKDEV(VIDEO_MAJOR, vfd->minor), 1);
+        if (ret < 0) {
+                printk(KERN_ERR "%s: cdev_add failed\n", __func__);
+                goto fail_minor;
+        }
         /* sysfs class */
-        memset(&vfd->dev, 0x00, sizeof(vfd->dev));
+        memset(&vfd->dev, 0, sizeof(vfd->dev));
+        /* The memset above cleared the device's drvdata, so
+           put back the copy we made earlier. */
+        video_set_drvdata(vfd, priv);
         vfd->dev.class = &video_class;
         vfd->dev.devt = MKDEV(VIDEO_MAJOR, vfd->minor);
         if (vfd->parent)
                 vfd->dev.parent = vfd->parent;
-        sprintf(vfd->dev.bus_id, "%s%d", name_base, i - base);
+        sprintf(vfd->dev.bus_id, "%s%d", name_base, nr);
         ret = device_register(&vfd->dev);
         if (ret < 0) {
                 printk(KERN_ERR "%s: device_register failed\n", __func__);
-                goto fail_minor;
+                goto del_cdev;
         }
-
-#if 1
-        /* needed until all drivers are fixed */
-        if (!vfd->release)
-                printk(KERN_WARNING "videodev: \"%s\" has no release callback. "
-                       "Please fix your driver for proper sysfs support, see "
-                       "http://lwn.net/Articles/36850/\n", vfd->name);
-#endif
+        /* Remember the cdev's release function */
+        vfd->cdev_release = vfd->cdev.kobj.ktype->release;
+        /* Install our own */
+        vfd->cdev.kobj.ktype = &v4l2_ktype_cdev_default;
         return 0;
 
+del_cdev:
+        cdev_del(&vfd->cdev);
+
 fail_minor:
         mutex_lock(&videodev_lock);
         video_device[vfd->minor] = NULL;
-        vfd->minor = -1;
+        clear_bit(vfd->num, video_nums[type]);
         mutex_unlock(&videodev_lock);
+        vfd->minor = -1;
         return ret;
 }
 EXPORT_SYMBOL(video_register_device_index);
@@ -363,42 +374,29 @@ EXPORT_SYMBOL(video_register_device_index);
 
 void video_unregister_device(struct video_device *vfd)
 {
-        mutex_lock(&videodev_lock);
-        if (video_device[vfd->minor] != vfd)
-                panic("videodev: bad unregister");
-
-        video_device[vfd->minor] = NULL;
         device_unregister(&vfd->dev);
-        mutex_unlock(&videodev_lock);
 }
 EXPORT_SYMBOL(video_unregister_device);
 
 /*
- * Video fs operations
- */
-static const struct file_operations video_fops = {
-        .owner          = THIS_MODULE,
-        .llseek         = no_llseek,
-        .open           = video_open,
-};
-
-/*
  *      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");
-        if (register_chrdev(VIDEO_MAJOR, VIDEO_NAME, &video_fops)) {
-                printk(KERN_WARNING "video_dev: unable to get major %d\n", VIDEO_MAJOR);
-                return -EIO;
+        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(VIDEO_MAJOR, VIDEO_NAME);
+                unregister_chrdev_region(dev, VIDEO_NUM_DEVICES);
                 printk(KERN_WARNING "video_dev: class_register failed\n");
                 return -EIO;
         }
@@ -408,8 +406,10 @@ static int __init videodev_init(void)
 
 static void __exit videodev_exit(void)
 {
+        dev_t dev = MKDEV(VIDEO_MAJOR, 0);
+
         class_unregister(&video_class);
-        unregister_chrdev(VIDEO_MAJOR, VIDEO_NAME);
+        unregister_chrdev_region(dev, VIDEO_NUM_DEVICES);
 }
 
 module_init(videodev_init)