V4L/DVB (8427): videodev: split off the ioctl handling into v4l2-ioctl.c
videodev.c became top-heavy so all the ioctl processing has been split off
into v4l2-ioctl.c. This means videodev.c is back to its original purpose:
creating and registering v4l devices.
Since videodev.c and v4l2-ioctl.c should still remain one module (as least
for now) I also had to rename videodev.c to v4l2-dev.c to prevent a
circular dependency when building a videodev.ko module. This is not a bad
thing, since the source and header now have the same name. And the v4l2-
prefix is useful to see which sources are generic v4l2 support code.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
new file mode 100644
index 0000000..2dd82b1
--- /dev/null
+++ b/drivers/media/video/v4l2-dev.c
@@ -0,0 +1,424 @@
+/*
+ * 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@redhat.com> (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 <linux/smp_lock.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+#include <media/v4l2-common.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 *vfd = container_of(cd, struct video_device,
+ class_dev);
+ return sprintf(buf, "%i\n", vfd->index);
+}
+
+static ssize_t show_name(struct device *cd,
+ struct device_attribute *attr, char *buf)
+{
+ struct video_device *vfd = container_of(cd, struct video_device,
+ class_dev);
+ return sprintf(buf, "%.*s\n", (int)sizeof(vfd->name), vfd->name);
+}
+
+static struct device_attribute video_device_attrs[] = {
+ __ATTR(name, S_IRUGO, show_name, NULL),
+ __ATTR(index, S_IRUGO, show_index, NULL),
+ __ATTR_NULL
+};
+
+struct video_device *video_device_alloc(void)
+{
+ struct video_device *vfd;
+
+ vfd = kzalloc(sizeof(*vfd), GFP_KERNEL);
+ return vfd;
+}
+EXPORT_SYMBOL(video_device_alloc);
+
+void video_device_release(struct video_device *vfd)
+{
+ kfree(vfd);
+}
+EXPORT_SYMBOL(video_device_release);
+
+static void video_release(struct device *cd)
+{
+ struct video_device *vfd = container_of(cd, struct video_device,
+ class_dev);
+
+#if 1
+ /* needed until all drivers are fixed */
+ if (!vfd->release)
+ return;
+#endif
+ vfd->release(vfd);
+}
+
+static struct class video_class = {
+ .name = VIDEO_NAME,
+ .dev_attrs = video_device_attrs,
+ .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
+ * @num: -1 if auto assign, requested number otherwise
+ *
+ *
+ * returns -ENFILE if num is already in use, a free index number if
+ * successful.
+ */
+static int get_index(struct video_device *vdev, int num)
+{
+ u32 used = 0;
+ const int max_index = sizeof(used) * 8 - 1;
+ 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) {
+ printk(KERN_ERR "videodev: %s num is too large\n", __func__);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < VIDEO_NUM_DEVICES; i++) {
+ if (video_device[i] != NULL &&
+ video_device[i] != vdev &&
+ video_device[i]->dev == vdev->dev) {
+ used |= 1 << video_device[i]->index;
+ }
+ }
+
+ if (num >= 0) {
+ if (used & (1 << num))
+ return -ENFILE;
+ return num;
+ }
+
+ i = ffz(used);
+ return i > max_index ? -ENFILE : i;
+}
+
+static const struct file_operations video_fops;
+
+int video_register_device(struct video_device *vfd, int type, int nr)
+{
+ return video_register_device_index(vfd, type, nr, -1);
+}
+EXPORT_SYMBOL(video_register_device);
+
+/**
+ * video_register_device - register video4linux devices
+ * @vfd: video device structure we want to register
+ * @type: type of device to register
+ * @nr: which device number (0 == /dev/video0, 1 == /dev/video1, ...
+ * -1 == first free)
+ *
+ * The registration code assigns minor numbers based on the type
+ * requested. -ENFILE is returned in all the device slots for this
+ * category are full. If not then the minor field is set and the
+ * driver initialize function is called (if non %NULL).
+ *
+ * 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
+ */
+
+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;
+
+ 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:
+ printk(KERN_ERR "%s called with unknown type: %d\n",
+ __func__, type);
+ return -1;
+ }
+
+ /* 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;
+ }
+ }
+ video_device[i] = vfd;
+ vfd->minor = i;
+
+ ret = get_index(vfd, index);
+ vfd->index = ret;
+
+ mutex_unlock(&videodev_lock);
+
+ if (ret < 0) {
+ printk(KERN_ERR "%s: get_index failed\n", __func__);
+ goto fail_minor;
+ }
+
+ mutex_init(&vfd->lock);
+
+ /* sysfs class */
+ memset(&vfd->class_dev, 0x00, sizeof(vfd->class_dev));
+ vfd->class_dev.class = &video_class;
+ vfd->class_dev.devt = MKDEV(VIDEO_MAJOR, vfd->minor);
+ if (vfd->dev)
+ vfd->class_dev.parent = vfd->dev;
+ sprintf(vfd->class_dev.bus_id, "%s%d", name_base, i - base);
+ ret = device_register(&vfd->class_dev);
+ if (ret < 0) {
+ printk(KERN_ERR "%s: device_register failed\n", __func__);
+ goto fail_minor;
+ }
+
+#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
+ return 0;
+
+fail_minor:
+ mutex_lock(&videodev_lock);
+ video_device[vfd->minor] = NULL;
+ vfd->minor = -1;
+ mutex_unlock(&videodev_lock);
+ return ret;
+}
+EXPORT_SYMBOL(video_register_device_index);
+
+/**
+ * video_unregister_device - unregister a video4linux device
+ * @vfd: the device to unregister
+ *
+ * This unregisters the passed device and deassigns the minor
+ * number. Future open calls will be met with errors.
+ */
+
+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->class_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)
+{
+ 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 = class_register(&video_class);
+ if (ret < 0) {
+ unregister_chrdev(VIDEO_MAJOR, VIDEO_NAME);
+ printk(KERN_WARNING "video_dev: class_register failed\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static void __exit videodev_exit(void)
+{
+ class_unregister(&video_class);
+ unregister_chrdev(VIDEO_MAJOR, VIDEO_NAME);
+}
+
+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");
+
+
+/*
+ * Local variables:
+ * c-basic-offset: 8
+ * End:
+ */