Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / media / v4l2-core / v4l2-dev.c
diff --git a/kernel/drivers/media/v4l2-core/v4l2-dev.c b/kernel/drivers/media/v4l2-core/v4l2-dev.c
new file mode 100644 (file)
index 0000000..71a1b93
--- /dev/null
@@ -0,0 +1,1008 @@
+/*
+ * 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 <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 index_show(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 DEVICE_ATTR_RO(index);
+
+static ssize_t dev_debug_show(struct device *cd,
+                         struct device_attribute *attr, char *buf)
+{
+       struct video_device *vdev = to_video_device(cd);
+
+       return sprintf(buf, "%i\n", vdev->dev_debug);
+}
+
+static ssize_t dev_debug_store(struct device *cd, struct device_attribute *attr,
+                         const char *buf, size_t len)
+{
+       struct video_device *vdev = to_video_device(cd);
+       int res = 0;
+       u16 value;
+
+       res = kstrtou16(buf, 0, &value);
+       if (res)
+               return res;
+
+       vdev->dev_debug = value;
+       return len;
+}
+static DEVICE_ATTR_RW(dev_debug);
+
+static ssize_t name_show(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 DEVICE_ATTR_RO(name);
+
+static struct attribute *video_device_attrs[] = {
+       &dev_attr_name.attr,
+       &dev_attr_dev_debug.attr,
+       &dev_attr_index.attr,
+       NULL,
+};
+ATTRIBUTE_GROUPS(video_device);
+
+/*
+ *     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_RADIO) ? 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);
+       struct v4l2_device *v4l2_dev = vdev->v4l2_dev;
+
+       mutex_lock(&videodev_lock);
+       if (WARN_ON(video_device[vdev->minor] != vdev)) {
+               /* should not happen */
+               mutex_unlock(&videodev_lock);
+               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);
+
+#if defined(CONFIG_MEDIA_CONTROLLER)
+       if (v4l2_dev->mdev &&
+           vdev->vfl_type != VFL_TYPE_SUBDEV)
+               media_device_unregister_entity(&vdev->entity);
+#endif
+
+       /* Do not call v4l2_device_put if there is no release callback set.
+        * Drivers that have no v4l2_device release callback might free the
+        * v4l2_dev instance in the video_device release callback below, so we
+        * must perform this check here.
+        *
+        * TODO: In the long run all drivers that use v4l2_device should use the
+        * v4l2_device release callback. This check will then be unnecessary.
+        */
+       if (v4l2_dev->release == NULL)
+               v4l2_dev = NULL;
+
+       /* Release video_device and perform other
+          cleanups as needed. */
+       vdev->release(vdev);
+
+       /* Decrease v4l2_device refcount */
+       if (v4l2_dev)
+               v4l2_device_put(v4l2_dev);
+}
+
+static struct class video_class = {
+       .name = VIDEO_NAME,
+       .dev_groups = video_device_groups,
+};
+
+struct video_device *video_devdata(struct file *file)
+{
+       return video_device[iminor(file_inode(file))];
+}
+EXPORT_SYMBOL(video_devdata);
+
+
+/* Priority handling */
+
+static inline bool prio_is_valid(enum v4l2_priority prio)
+{
+       return prio == V4L2_PRIORITY_BACKGROUND ||
+              prio == V4L2_PRIORITY_INTERACTIVE ||
+              prio == V4L2_PRIORITY_RECORD;
+}
+
+void v4l2_prio_init(struct v4l2_prio_state *global)
+{
+       memset(global, 0, sizeof(*global));
+}
+EXPORT_SYMBOL(v4l2_prio_init);
+
+int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
+                    enum v4l2_priority new)
+{
+       if (!prio_is_valid(new))
+               return -EINVAL;
+       if (*local == new)
+               return 0;
+
+       atomic_inc(&global->prios[new]);
+       if (prio_is_valid(*local))
+               atomic_dec(&global->prios[*local]);
+       *local = new;
+       return 0;
+}
+EXPORT_SYMBOL(v4l2_prio_change);
+
+void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local)
+{
+       v4l2_prio_change(global, local, V4L2_PRIORITY_DEFAULT);
+}
+EXPORT_SYMBOL(v4l2_prio_open);
+
+void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local)
+{
+       if (prio_is_valid(local))
+               atomic_dec(&global->prios[local]);
+}
+EXPORT_SYMBOL(v4l2_prio_close);
+
+enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global)
+{
+       if (atomic_read(&global->prios[V4L2_PRIORITY_RECORD]) > 0)
+               return V4L2_PRIORITY_RECORD;
+       if (atomic_read(&global->prios[V4L2_PRIORITY_INTERACTIVE]) > 0)
+               return V4L2_PRIORITY_INTERACTIVE;
+       if (atomic_read(&global->prios[V4L2_PRIORITY_BACKGROUND]) > 0)
+               return V4L2_PRIORITY_BACKGROUND;
+       return V4L2_PRIORITY_UNSET;
+}
+EXPORT_SYMBOL(v4l2_prio_max);
+
+int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local)
+{
+       return (local < v4l2_prio_max(global)) ? -EBUSY : 0;
+}
+EXPORT_SYMBOL(v4l2_prio_check);
+
+
+static ssize_t v4l2_read(struct file *filp, char __user *buf,
+               size_t sz, loff_t *off)
+{
+       struct video_device *vdev = video_devdata(filp);
+       int ret = -ENODEV;
+
+       if (!vdev->fops->read)
+               return -EINVAL;
+       if (video_is_registered(vdev))
+               ret = vdev->fops->read(filp, buf, sz, off);
+       if ((vdev->dev_debug & V4L2_DEV_DEBUG_FOP) &&
+           (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING))
+               printk(KERN_DEBUG "%s: read: %zd (%d)\n",
+                       video_device_node_name(vdev), sz, ret);
+       return ret;
+}
+
+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);
+       int ret = -ENODEV;
+
+       if (!vdev->fops->write)
+               return -EINVAL;
+       if (video_is_registered(vdev))
+               ret = vdev->fops->write(filp, buf, sz, off);
+       if ((vdev->dev_debug & V4L2_DEV_DEBUG_FOP) &&
+           (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING))
+               printk(KERN_DEBUG "%s: write: %zd (%d)\n",
+                       video_device_node_name(vdev), sz, ret);
+       return ret;
+}
+
+static unsigned int v4l2_poll(struct file *filp, struct poll_table_struct *poll)
+{
+       struct video_device *vdev = video_devdata(filp);
+       unsigned int res = POLLERR | POLLHUP;
+
+       if (!vdev->fops->poll)
+               return DEFAULT_POLLMASK;
+       if (video_is_registered(vdev))
+               res = vdev->fops->poll(filp, poll);
+       if (vdev->dev_debug & V4L2_DEV_DEBUG_POLL)
+               printk(KERN_DEBUG "%s: poll: %08x\n",
+                       video_device_node_name(vdev), res);
+       return res;
+}
+
+static long v4l2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+       struct video_device *vdev = video_devdata(filp);
+       int ret = -ENODEV;
+
+       if (vdev->fops->unlocked_ioctl) {
+               struct mutex *lock = v4l2_ioctl_get_lock(vdev, cmd);
+
+               if (lock && mutex_lock_interruptible(lock))
+                       return -ERESTARTSYS;
+               if (video_is_registered(vdev))
+                       ret = vdev->fops->unlocked_ioctl(filp, cmd, arg);
+               if (lock)
+                       mutex_unlock(lock);
+       } else
+               ret = -ENOTTY;
+
+       return ret;
+}
+
+#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);
+       int ret;
+
+       if (!vdev->fops->get_unmapped_area)
+               return -ENOSYS;
+       if (!video_is_registered(vdev))
+               return -ENODEV;
+       ret = vdev->fops->get_unmapped_area(filp, addr, len, pgoff, flags);
+       if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
+               printk(KERN_DEBUG "%s: get_unmapped_area (%d)\n",
+                       video_device_node_name(vdev), ret);
+       return ret;
+}
+#endif
+
+static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm)
+{
+       struct video_device *vdev = video_devdata(filp);
+       int ret = -ENODEV;
+
+       if (!vdev->fops->mmap)
+               return -ENODEV;
+       if (video_is_registered(vdev))
+               ret = vdev->fops->mmap(filp, vm);
+       if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
+               printk(KERN_DEBUG "%s: mmap (%d)\n",
+                       video_device_node_name(vdev), ret);
+       return ret;
+}
+
+/* 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 already been removed. */
+       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) {
+               if (video_is_registered(vdev))
+                       ret = vdev->fops->open(filp);
+               else
+                       ret = -ENODEV;
+       }
+
+       if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
+               printk(KERN_DEBUG "%s: open (%d)\n",
+                       video_device_node_name(vdev), ret);
+       /* 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)
+               ret = vdev->fops->release(filp);
+       if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
+               printk(KERN_DEBUG "%s: release\n",
+                       video_device_node_name(vdev));
+
+       /* decrease the refcount unconditionally since the release()
+          return value is ignored. */
+       video_put(vdev);
+       return ret;
+}
+
+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,
+       .unlocked_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 v4l2_dev
+ * @vdev: video_device to assign index number to, vdev->v4l2_dev 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;
+
+       bitmap_zero(used, VIDEO_NUM_DEVICES);
+
+       for (i = 0; i < VIDEO_NUM_DEVICES; i++) {
+               if (video_device[i] != NULL &&
+                   video_device[i]->v4l2_dev == vdev->v4l2_dev) {
+                       set_bit(video_device[i]->index, used);
+               }
+       }
+
+       return find_first_zero_bit(used, VIDEO_NUM_DEVICES);
+}
+
+#define SET_VALID_IOCTL(ops, cmd, op)                  \
+       if (ops->op)                                    \
+               set_bit(_IOC_NR(cmd), valid_ioctls)
+
+/* This determines which ioctls are actually implemented in the driver.
+   It's a one-time thing which simplifies video_ioctl2 as it can just do
+   a bit test.
+
+   Note that drivers can override this by setting bits to 1 in
+   vdev->valid_ioctls. If an ioctl is marked as 1 when this function is
+   called, then that ioctl will actually be marked as unimplemented.
+
+   It does that by first setting up the local valid_ioctls bitmap, and
+   at the end do a:
+
+   vdev->valid_ioctls = valid_ioctls & ~(vdev->valid_ioctls)
+ */
+static void determine_valid_ioctls(struct video_device *vdev)
+{
+       DECLARE_BITMAP(valid_ioctls, BASE_VIDIOC_PRIVATE);
+       const struct v4l2_ioctl_ops *ops = vdev->ioctl_ops;
+       bool is_vid = vdev->vfl_type == VFL_TYPE_GRABBER;
+       bool is_vbi = vdev->vfl_type == VFL_TYPE_VBI;
+       bool is_radio = vdev->vfl_type == VFL_TYPE_RADIO;
+       bool is_sdr = vdev->vfl_type == VFL_TYPE_SDR;
+       bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
+       bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
+
+       bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);
+
+       /* vfl_type and vfl_dir independent ioctls */
+
+       SET_VALID_IOCTL(ops, VIDIOC_QUERYCAP, vidioc_querycap);
+       set_bit(_IOC_NR(VIDIOC_G_PRIORITY), valid_ioctls);
+       set_bit(_IOC_NR(VIDIOC_S_PRIORITY), valid_ioctls);
+
+       /* Note: the control handler can also be passed through the filehandle,
+          and that can't be tested here. If the bit for these control ioctls
+          is set, then the ioctl is valid. But if it is 0, then it can still
+          be valid if the filehandle passed the control handler. */
+       if (vdev->ctrl_handler || ops->vidioc_queryctrl)
+               set_bit(_IOC_NR(VIDIOC_QUERYCTRL), valid_ioctls);
+       if (vdev->ctrl_handler || ops->vidioc_query_ext_ctrl)
+               set_bit(_IOC_NR(VIDIOC_QUERY_EXT_CTRL), valid_ioctls);
+       if (vdev->ctrl_handler || ops->vidioc_g_ctrl || ops->vidioc_g_ext_ctrls)
+               set_bit(_IOC_NR(VIDIOC_G_CTRL), valid_ioctls);
+       if (vdev->ctrl_handler || ops->vidioc_s_ctrl || ops->vidioc_s_ext_ctrls)
+               set_bit(_IOC_NR(VIDIOC_S_CTRL), valid_ioctls);
+       if (vdev->ctrl_handler || ops->vidioc_g_ext_ctrls)
+               set_bit(_IOC_NR(VIDIOC_G_EXT_CTRLS), valid_ioctls);
+       if (vdev->ctrl_handler || ops->vidioc_s_ext_ctrls)
+               set_bit(_IOC_NR(VIDIOC_S_EXT_CTRLS), valid_ioctls);
+       if (vdev->ctrl_handler || ops->vidioc_try_ext_ctrls)
+               set_bit(_IOC_NR(VIDIOC_TRY_EXT_CTRLS), valid_ioctls);
+       if (vdev->ctrl_handler || ops->vidioc_querymenu)
+               set_bit(_IOC_NR(VIDIOC_QUERYMENU), valid_ioctls);
+       SET_VALID_IOCTL(ops, VIDIOC_G_FREQUENCY, vidioc_g_frequency);
+       SET_VALID_IOCTL(ops, VIDIOC_S_FREQUENCY, vidioc_s_frequency);
+       SET_VALID_IOCTL(ops, VIDIOC_LOG_STATUS, vidioc_log_status);
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+       set_bit(_IOC_NR(VIDIOC_DBG_G_CHIP_INFO), valid_ioctls);
+       set_bit(_IOC_NR(VIDIOC_DBG_G_REGISTER), valid_ioctls);
+       set_bit(_IOC_NR(VIDIOC_DBG_S_REGISTER), valid_ioctls);
+#endif
+       /* yes, really vidioc_subscribe_event */
+       SET_VALID_IOCTL(ops, VIDIOC_DQEVENT, vidioc_subscribe_event);
+       SET_VALID_IOCTL(ops, VIDIOC_SUBSCRIBE_EVENT, vidioc_subscribe_event);
+       SET_VALID_IOCTL(ops, VIDIOC_UNSUBSCRIBE_EVENT, vidioc_unsubscribe_event);
+       if (ops->vidioc_enum_freq_bands || ops->vidioc_g_tuner || ops->vidioc_g_modulator)
+               set_bit(_IOC_NR(VIDIOC_ENUM_FREQ_BANDS), valid_ioctls);
+
+       if (is_vid) {
+               /* video specific ioctls */
+               if ((is_rx && (ops->vidioc_enum_fmt_vid_cap ||
+                              ops->vidioc_enum_fmt_vid_cap_mplane ||
+                              ops->vidioc_enum_fmt_vid_overlay)) ||
+                   (is_tx && (ops->vidioc_enum_fmt_vid_out ||
+                              ops->vidioc_enum_fmt_vid_out_mplane)))
+                       set_bit(_IOC_NR(VIDIOC_ENUM_FMT), valid_ioctls);
+               if ((is_rx && (ops->vidioc_g_fmt_vid_cap ||
+                              ops->vidioc_g_fmt_vid_cap_mplane ||
+                              ops->vidioc_g_fmt_vid_overlay)) ||
+                   (is_tx && (ops->vidioc_g_fmt_vid_out ||
+                              ops->vidioc_g_fmt_vid_out_mplane ||
+                              ops->vidioc_g_fmt_vid_out_overlay)))
+                        set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
+               if ((is_rx && (ops->vidioc_s_fmt_vid_cap ||
+                              ops->vidioc_s_fmt_vid_cap_mplane ||
+                              ops->vidioc_s_fmt_vid_overlay)) ||
+                   (is_tx && (ops->vidioc_s_fmt_vid_out ||
+                              ops->vidioc_s_fmt_vid_out_mplane ||
+                              ops->vidioc_s_fmt_vid_out_overlay)))
+                        set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
+               if ((is_rx && (ops->vidioc_try_fmt_vid_cap ||
+                              ops->vidioc_try_fmt_vid_cap_mplane ||
+                              ops->vidioc_try_fmt_vid_overlay)) ||
+                   (is_tx && (ops->vidioc_try_fmt_vid_out ||
+                              ops->vidioc_try_fmt_vid_out_mplane ||
+                              ops->vidioc_try_fmt_vid_out_overlay)))
+                        set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
+               SET_VALID_IOCTL(ops, VIDIOC_OVERLAY, vidioc_overlay);
+               SET_VALID_IOCTL(ops, VIDIOC_G_FBUF, vidioc_g_fbuf);
+               SET_VALID_IOCTL(ops, VIDIOC_S_FBUF, vidioc_s_fbuf);
+               SET_VALID_IOCTL(ops, VIDIOC_G_JPEGCOMP, vidioc_g_jpegcomp);
+               SET_VALID_IOCTL(ops, VIDIOC_S_JPEGCOMP, vidioc_s_jpegcomp);
+               SET_VALID_IOCTL(ops, VIDIOC_G_ENC_INDEX, vidioc_g_enc_index);
+               SET_VALID_IOCTL(ops, VIDIOC_ENCODER_CMD, vidioc_encoder_cmd);
+               SET_VALID_IOCTL(ops, VIDIOC_TRY_ENCODER_CMD, vidioc_try_encoder_cmd);
+               SET_VALID_IOCTL(ops, VIDIOC_DECODER_CMD, vidioc_decoder_cmd);
+               SET_VALID_IOCTL(ops, VIDIOC_TRY_DECODER_CMD, vidioc_try_decoder_cmd);
+               SET_VALID_IOCTL(ops, VIDIOC_ENUM_FRAMESIZES, vidioc_enum_framesizes);
+               SET_VALID_IOCTL(ops, VIDIOC_ENUM_FRAMEINTERVALS, vidioc_enum_frameintervals);
+               if (ops->vidioc_g_crop || ops->vidioc_g_selection)
+                       set_bit(_IOC_NR(VIDIOC_G_CROP), valid_ioctls);
+               if (ops->vidioc_s_crop || ops->vidioc_s_selection)
+                       set_bit(_IOC_NR(VIDIOC_S_CROP), valid_ioctls);
+               SET_VALID_IOCTL(ops, VIDIOC_G_SELECTION, vidioc_g_selection);
+               SET_VALID_IOCTL(ops, VIDIOC_S_SELECTION, vidioc_s_selection);
+               if (ops->vidioc_cropcap || ops->vidioc_g_selection)
+                       set_bit(_IOC_NR(VIDIOC_CROPCAP), valid_ioctls);
+       } else if (is_vbi) {
+               /* vbi specific ioctls */
+               if ((is_rx && (ops->vidioc_g_fmt_vbi_cap ||
+                              ops->vidioc_g_fmt_sliced_vbi_cap)) ||
+                   (is_tx && (ops->vidioc_g_fmt_vbi_out ||
+                              ops->vidioc_g_fmt_sliced_vbi_out)))
+                       set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
+               if ((is_rx && (ops->vidioc_s_fmt_vbi_cap ||
+                              ops->vidioc_s_fmt_sliced_vbi_cap)) ||
+                   (is_tx && (ops->vidioc_s_fmt_vbi_out ||
+                              ops->vidioc_s_fmt_sliced_vbi_out)))
+                       set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
+               if ((is_rx && (ops->vidioc_try_fmt_vbi_cap ||
+                              ops->vidioc_try_fmt_sliced_vbi_cap)) ||
+                   (is_tx && (ops->vidioc_try_fmt_vbi_out ||
+                              ops->vidioc_try_fmt_sliced_vbi_out)))
+                       set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
+               SET_VALID_IOCTL(ops, VIDIOC_G_SLICED_VBI_CAP, vidioc_g_sliced_vbi_cap);
+       } else if (is_sdr) {
+               /* SDR specific ioctls */
+               if (ops->vidioc_enum_fmt_sdr_cap)
+                       set_bit(_IOC_NR(VIDIOC_ENUM_FMT), valid_ioctls);
+               if (ops->vidioc_g_fmt_sdr_cap)
+                       set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
+               if (ops->vidioc_s_fmt_sdr_cap)
+                       set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
+               if (ops->vidioc_try_fmt_sdr_cap)
+                       set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
+       }
+
+       if (is_vid || is_vbi || is_sdr) {
+               /* ioctls valid for video, vbi or sdr */
+               SET_VALID_IOCTL(ops, VIDIOC_REQBUFS, vidioc_reqbufs);
+               SET_VALID_IOCTL(ops, VIDIOC_QUERYBUF, vidioc_querybuf);
+               SET_VALID_IOCTL(ops, VIDIOC_QBUF, vidioc_qbuf);
+               SET_VALID_IOCTL(ops, VIDIOC_EXPBUF, vidioc_expbuf);
+               SET_VALID_IOCTL(ops, VIDIOC_DQBUF, vidioc_dqbuf);
+               SET_VALID_IOCTL(ops, VIDIOC_CREATE_BUFS, vidioc_create_bufs);
+               SET_VALID_IOCTL(ops, VIDIOC_PREPARE_BUF, vidioc_prepare_buf);
+               SET_VALID_IOCTL(ops, VIDIOC_STREAMON, vidioc_streamon);
+               SET_VALID_IOCTL(ops, VIDIOC_STREAMOFF, vidioc_streamoff);
+       }
+
+       if (is_vid || is_vbi) {
+               /* ioctls valid for video or vbi */
+               if (ops->vidioc_s_std)
+                       set_bit(_IOC_NR(VIDIOC_ENUMSTD), valid_ioctls);
+               SET_VALID_IOCTL(ops, VIDIOC_S_STD, vidioc_s_std);
+               SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
+               if (is_rx) {
+                       SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
+                       SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
+                       SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
+                       SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
+                       SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
+                       SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
+                       SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
+                       SET_VALID_IOCTL(ops, VIDIOC_QUERY_DV_TIMINGS, vidioc_query_dv_timings);
+                       SET_VALID_IOCTL(ops, VIDIOC_S_EDID, vidioc_s_edid);
+               }
+               if (is_tx) {
+                       SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
+                       SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
+                       SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
+                       SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDOUT, vidioc_enumaudout);
+                       SET_VALID_IOCTL(ops, VIDIOC_G_AUDOUT, vidioc_g_audout);
+                       SET_VALID_IOCTL(ops, VIDIOC_S_AUDOUT, vidioc_s_audout);
+               }
+               if (ops->vidioc_g_parm || (vdev->vfl_type == VFL_TYPE_GRABBER &&
+                                       ops->vidioc_g_std))
+                       set_bit(_IOC_NR(VIDIOC_G_PARM), valid_ioctls);
+               SET_VALID_IOCTL(ops, VIDIOC_S_PARM, vidioc_s_parm);
+               SET_VALID_IOCTL(ops, VIDIOC_S_DV_TIMINGS, vidioc_s_dv_timings);
+               SET_VALID_IOCTL(ops, VIDIOC_G_DV_TIMINGS, vidioc_g_dv_timings);
+               SET_VALID_IOCTL(ops, VIDIOC_ENUM_DV_TIMINGS, vidioc_enum_dv_timings);
+               SET_VALID_IOCTL(ops, VIDIOC_DV_TIMINGS_CAP, vidioc_dv_timings_cap);
+               SET_VALID_IOCTL(ops, VIDIOC_G_EDID, vidioc_g_edid);
+       }
+       if (is_tx && (is_radio || is_sdr)) {
+               /* radio transmitter only ioctls */
+               SET_VALID_IOCTL(ops, VIDIOC_G_MODULATOR, vidioc_g_modulator);
+               SET_VALID_IOCTL(ops, VIDIOC_S_MODULATOR, vidioc_s_modulator);
+       }
+       if (is_rx) {
+               /* receiver only ioctls */
+               SET_VALID_IOCTL(ops, VIDIOC_G_TUNER, vidioc_g_tuner);
+               SET_VALID_IOCTL(ops, VIDIOC_S_TUNER, vidioc_s_tuner);
+               SET_VALID_IOCTL(ops, VIDIOC_S_HW_FREQ_SEEK, vidioc_s_hw_freq_seek);
+       }
+
+       bitmap_andnot(vdev->valid_ioctls, valid_ioctls, vdev->valid_ioctls,
+                       BASE_VIDIOC_PRIVATE);
+}
+
+/**
+ *     __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.
+ *     @owner: module that owns the video device node
+ *
+ *     The registration code assigns minor numbers and device node numbers
+ *     based on the requested type and registers the new device node with
+ *     the kernel.
+ *
+ *     This function assumes that struct video_device was zeroed when it
+ *     was allocated and does not contain any stale date.
+ *
+ *     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_VBI - Vertical blank data (undecoded)
+ *
+ *     %VFL_TYPE_RADIO - A radio card
+ *
+ *     %VFL_TYPE_SUBDEV - A subdevice
+ *
+ *     %VFL_TYPE_SDR - Software Defined Radio
+ */
+int __video_register_device(struct video_device *vdev, int type, int nr,
+               int warn_if_nr_in_use, struct module *owner)
+{
+       int i = 0;
+       int ret;
+       int minor_offset = 0;
+       int minor_cnt = VIDEO_NUM_DEVICES;
+       const char *name_base;
+
+       /* A minor value of -1 marks this video device as never
+          having been registered */
+       vdev->minor = -1;
+
+       /* the release callback MUST be present */
+       if (WARN_ON(!vdev->release))
+               return -EINVAL;
+       /* the v4l2_dev pointer MUST be present */
+       if (WARN_ON(!vdev->v4l2_dev))
+               return -EINVAL;
+
+       /* v4l2_fh support */
+       spin_lock_init(&vdev->fh_lock);
+       INIT_LIST_HEAD(&vdev->fh_list);
+
+       /* Part 1: check device type */
+       switch (type) {
+       case VFL_TYPE_GRABBER:
+               name_base = "video";
+               break;
+       case VFL_TYPE_VBI:
+               name_base = "vbi";
+               break;
+       case VFL_TYPE_RADIO:
+               name_base = "radio";
+               break;
+       case VFL_TYPE_SUBDEV:
+               name_base = "v4l-subdev";
+               break;
+       case VFL_TYPE_SDR:
+               /* Use device name 'swradio' because 'sdr' was already taken. */
+               name_base = "swradio";
+               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->dev_parent == NULL)
+               vdev->dev_parent = vdev->v4l2_dev->dev;
+       if (vdev->ctrl_handler == NULL)
+               vdev->ctrl_handler = vdev->v4l2_dev->ctrl_handler;
+       /* If the prio state pointer is NULL, then use the v4l2_device
+          prio state. */
+       if (vdev->prio == NULL)
+               vdev->prio = &vdev->v4l2_dev->prio;
+
+       /* 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_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);
+       video_device[vdev->minor] = vdev;
+       mutex_unlock(&videodev_lock);
+
+       if (vdev->ioctl_ops)
+               determine_valid_ioctls(vdev);
+
+       /* Part 3: Initialize the character device */
+       vdev->cdev = cdev_alloc();
+       if (vdev->cdev == NULL) {
+               ret = -ENOMEM;
+               goto cleanup;
+       }
+       vdev->cdev->ops = &v4l2_fops;
+       vdev->cdev->owner = 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 */
+       vdev->dev.class = &video_class;
+       vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor);
+       vdev->dev.parent = vdev->dev_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));
+
+       /* Increase v4l2_device refcount */
+       v4l2_device_get(vdev->v4l2_dev);
+
+#if defined(CONFIG_MEDIA_CONTROLLER)
+       /* Part 5: Register the entity. */
+       if (vdev->v4l2_dev->mdev &&
+           vdev->vfl_type != VFL_TYPE_SUBDEV) {
+               vdev->entity.type = MEDIA_ENT_T_DEVNODE_V4L;
+               vdev->entity.name = vdev->name;
+               vdev->entity.info.dev.major = VIDEO_MAJOR;
+               vdev->entity.info.dev.minor = vdev->minor;
+               ret = media_device_register_entity(vdev->v4l2_dev->mdev,
+                       &vdev->entity);
+               if (ret < 0)
+                       printk(KERN_WARNING
+                              "%s: media_device_register_entity failed\n",
+                              __func__);
+       }
+#endif
+       /* Part 6: Activate this minor. The char device can now be used. */
+       set_bit(V4L2_FL_REGISTERED, &vdev->flags);
+
+       return 0;
+
+cleanup:
+       mutex_lock(&videodev_lock);
+       if (vdev->cdev)
+               cdev_del(vdev->cdev);
+       video_device[vdev->minor] = NULL;
+       devnode_clear(vdev);
+       mutex_unlock(&videodev_lock);
+       /* Mark this video device as never having been registered. */
+       vdev->minor = -1;
+       return ret;
+}
+EXPORT_SYMBOL(__video_register_device);
+
+/**
+ *     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);
+       /* This must be in a critical section to prevent a race with v4l2_open.
+        * Once this bit has been cleared video_get may never be called again.
+        */
+       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);
+}
+
+subsys_initcall(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);