Hello,
Attached to this message is a patch against 2.4.0-test8 with my
video4linux loopback driver.
I makes two video devices for each pipe created, one for input using
write and one for output using read or mmap.
Jeroen
diff -ruN linux/CREDITS linux-2.4.0-test8/CREDITS
--- linux/CREDITS Fri Sep 8 21:38:00 2000
+++ linux-2.4.0-test8/CREDITS Mon Sep 11 17:10:51 2000
@@ -2734,6 +2734,14 @@
S: 1098 VA Amsterdam
S: The Netherlands
+N: Jeroen Vreeken
+E: pe1rxq@xxxxxxxxx
+W: http://www.chello.nl/~j.vreeken/
+D: Video4linux loopback driver
+S: Maastrichterweg 63
+S: 5554 GG Valkenswaard
+S: The Netherlands
+
N: Peter Shaobo Wang
E: pwang@xxxxxxxxxxx
W: http://www.mmdcorp.com/pw/linux
diff -ruN linux/drivers/media/video/Config.in linux-2.4.0-test8/drivers/media/video/Config.in
--- linux/drivers/media/video/Config.in Wed Aug 23 23:59:55 2000
+++ linux-2.4.0-test8/drivers/media/video/Config.in Mon Sep 11 17:10:51 2000
@@ -38,6 +38,7 @@
fi
dep_tristate ' Stradis 4:2:2 MPEG-2 video driver (EXPERIMENTAL)' CONFIG_VIDEO_STRADIS $CONFIG_VIDEO_DEV $CONFIG_PCI
fi
+dep_tristate ' Video For Linux loopback' CONFIG_VIDEO_VLOOPBACK $CONFIG_VIDEO_DEV
dep_tristate ' Zoran ZR36057/36060 Video For Linux' CONFIG_VIDEO_ZORAN $CONFIG_VIDEO_DEV $CONFIG_PCI $CONFIG_I2C
dep_tristate ' Include support for Iomega Buz' CONFIG_VIDEO_BUZ $CONFIG_VIDEO_ZORAN
dep_tristate ' Zoran ZR36120/36125 Video For Linux' CONFIG_VIDEO_ZR36120 $CONFIG_VIDEO_DEV $CONFIG_PCI $CONFIG_I2C
diff -ruN linux/drivers/media/video/Makefile linux-2.4.0-test8/drivers/media/video/Makefile
--- linux/drivers/media/video/Makefile Tue Aug 22 20:29:02 2000
+++ linux-2.4.0-test8/drivers/media/video/Makefile Mon Sep 11 17:10:51 2000
@@ -57,6 +57,7 @@
obj-$(CONFIG_VIDEO_CPIA) += cpia.o
obj-$(CONFIG_VIDEO_CPIA_PP) += cpia_pp.o
obj-$(CONFIG_VIDEO_CPIA_USB) += cpia_usb.o
+obj-$(CONFIG_VIDEO_VLOOPBACK) += vloopback.o
obj-$(CONFIG_TUNER_3036) += tuner-3036.o
# Extract lists of the multi-part drivers.
diff -ruN linux/drivers/media/video/vloopback.c linux-2.4.0-test8/drivers/media/video/vloopback.c
--- linux/drivers/media/video/vloopback.c Thu Jan 1 01:00:00 1970
+++ linux-2.4.0-test8/drivers/media/video/vloopback.c Mon Sep 11 17:11:12 2000
@@ -0,0 +1,816 @@
+/*
+ * vloopback.c
+ *
+ * Copyright Jeroen Vreeken (pe1rxq@xxxxxxxxx), 2000
+ *
+ * Published under the GNU Public License.
+ *
+ *
+ * UPDATED: Jeroen Vreeken.
+ * Added locks for smp machines. UNTESTED!
+ * Made the driver much more cpu friendly by using
+ * a wait queue.
+ * Went from vmalloc to rvmalloc (yes, I stole the code
+ * like everybody else) and implemented mmap.
+ * Implemented VIDIOCGUNIT and removed size/palette checks
+ * in VIDIOCSYNC.
+ * Cleaned up a lot of code.
+ * Changed locks to semaphores.
+ * Disabled changing size while somebody is using mmap
+ * Changed mapped check to open check, also don't allow
+ * a open for write while somebody is reading.
+ * Added /proc support
+ */
+#define VLNAME "vloopback: "
+#define VLVER "0.7"
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/malloc.h>
+#include <linux/vmalloc.h>
+#include <linux/wrapper.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/videodev.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+
+struct vloopback_device {
+ struct video_device viddev;
+ int pipenr;
+ int in;
+};
+
+struct vloopback_pipe {
+ struct vloopback_device *vloopin;
+ struct vloopback_device *vloopout;
+ char *buffer;
+ unsigned long buflength;
+ unsigned int width, height;
+ unsigned int palette;
+ unsigned long frameswrite;
+ unsigned long framesread;
+ unsigned long framesdumped;
+ unsigned int wopen;
+ unsigned int ropen;
+ struct proc_dir_entry *proc_entry;
+ struct semaphore lock;
+ wait_queue_head_t wait;
+};
+
+#define MAX_PIPES 16
+static struct vloopback_pipe *loops[MAX_PIPES];
+static int nr_o_pipes=0;
+static int pipes=-1;
+
+
+/**********************************************************************
+ *
+ * Memory management
+ *
+ * This is a shameless copy from the USB-cpia driver (linux kernel
+ * version 2.3.29 or so, I have no idea what this code actually does ;).
+ * Actually it seems to be a copy of a shameless copy of the bttv-driver.
+ * Or that is a copy of a shameless copy of ... (To the powers: is there
+ * no generic kernel-function to do this sort of stuff?)
+ *
+ * Yes, it was a shameless copy from the bttv-driver. IIRC, Alan says
+ * there will be one, but apparentely not yet -jerdfelt
+ *
+ * So I copied it again for the OV511 driver -claudio
+ *
+ * And it gets copied and copied and copied..... -Jeroen
+ *
+ **********************************************************************/
+
+/* Given PGD from the address space's page table, return the kernel
+ * virtual mapping of the physical memory mapped at ADR.
+ */
+static inline unsigned long uvirt_to_kva(pgd_t *pgd, unsigned long adr)
+{
+ unsigned long ret = 0UL;
+ pmd_t *pmd;
+ pte_t *ptep, pte;
+
+ if (!pgd_none(*pgd)) {
+ pmd = pmd_offset(pgd, adr);
+ if (!pmd_none(*pmd)) {
+ ptep = pte_offset(pmd, adr);
+ pte = *ptep;
+ if (pte_present(pte)) {
+ ret = (unsigned long) page_address(pte_page(pte));
+ ret |= (adr & (PAGE_SIZE - 1));
+ }
+ }
+ }
+
+ return ret;
+}
+
+/* Here we want the physical address of the memory.
+ * This is used when initializing the contents of the
+ * area and marking the pages as reserved.
+ */
+static inline unsigned long kvirt_to_pa(unsigned long adr)
+{
+ unsigned long va, kva, ret;
+
+ va = VMALLOC_VMADDR(adr);
+ kva = uvirt_to_kva(pgd_offset_k(va), va);
+ ret = __pa(kva);
+ return ret;
+}
+
+static void *rvmalloc(unsigned long size)
+{
+ void *mem;
+ unsigned long adr, page;
+
+ /* Round it off to PAGE_SIZE */
+ size += (PAGE_SIZE - 1);
+ size &= ~(PAGE_SIZE - 1);
+
+ mem = vmalloc_32(size);
+ if (!mem)
+ return NULL;
+
+ memset(mem, 0, size); /* Clear the ram out, no junk to the user */
+ adr = (unsigned long) mem;
+ while (size > 0) {
+ page = kvirt_to_pa(adr);
+ mem_map_reserve(virt_to_page(__va(page)));
+ adr += PAGE_SIZE;
+ if (size > PAGE_SIZE)
+ size -= PAGE_SIZE;
+ else
+ size = 0;
+ }
+
+ return mem;
+}
+
+static void rvfree(void *mem, unsigned long size)
+{
+ unsigned long adr, page;
+
+ if (!mem)
+ return;
+
+ size += (PAGE_SIZE - 1);
+ size &= ~(PAGE_SIZE - 1);
+
+ adr=(unsigned long) mem;
+ while (size > 0) {
+ page = kvirt_to_pa(adr);
+ mem_map_unreserve(virt_to_page(__va(page)));
+ adr += PAGE_SIZE;
+ if (size > PAGE_SIZE)
+ size -= PAGE_SIZE;
+ else
+ size = 0;
+ }
+ vfree(mem);
+}
+
+/**********************************************************************
+ *
+ * End of memory stuff, the rest is mine :)
+ *
+ **********************************************************************/
+
+
+static int vloopback_open(struct video_device *dev, int flags)
+{
+ struct vloopback_device *loopdev=(struct vloopback_device *)dev;
+ int nr=loopdev->pipenr;
+
+ /* Only allow a output to be opened if there is someone feeding
+ * the pipe.
+ */
+ if (!loopdev->in) {
+ if (loops[nr]->buffer==NULL) {
+ return -EINVAL;
+ }
+ loops[nr]->framesread=0;
+ loops[nr]->ropen=1;
+ } else {
+ if (loops[nr]->ropen)
+ return -EBUSY;
+ loops[nr]->frameswrite=0;
+ loops[nr]->wopen=1;
+ }
+
+ MOD_INC_USE_COUNT;
+ return 0;
+}
+
+static void vloopback_close(struct video_device *dev)
+{
+ struct vloopback_device *loopdev=(struct vloopback_device *)dev;
+ int nr=loopdev->pipenr;
+
+ if (loopdev->in) {
+ down(&loops[nr]->lock);
+ if (loops[nr]->buffer) {
+ rvfree(loops[nr]->buffer,
+ loops[nr]->buflength);
+ loops[nr]->buffer=NULL;
+ }
+ up(&loops[nr]->lock);
+ if (waitqueue_active(&loops[nr]->wait))
+ wake_up(&loops[nr]->wait);
+
+ loops[nr]->width=0;
+ loops[nr]->height=0;
+ loops[nr]->palette=0;
+ printk (VLNAME "frames written: %ld, frames dumped: %ld\n",
+ loops[nr]->frameswrite,
+ loops[nr]->framesdumped);
+ loops[nr]->wopen=0;
+ } else {
+ loops[nr]->ropen=0;
+ printk (VLNAME "frames read: %ld\n",
+ loops[nr]->framesread);
+ }
+
+ MOD_DEC_USE_COUNT;
+}
+
+static int vloopback_init_done(struct video_device *dev)
+{
+ return 0;
+}
+
+static long vloopback_write(struct video_device *v, const char *buf, unsigned long count, int noblock)
+{
+ struct vloopback_device *loopdev=(struct vloopback_device *)v;
+ int nr=loopdev->pipenr;
+ unsigned long realcount=count;
+
+ if (!loopdev->in) return -EINVAL;
+
+ if (loops[nr]->buffer==NULL) {
+ return -EINVAL;
+ }
+
+ /* Anybody want some pictures??? */
+ if (!waitqueue_active(&loops[nr]->wait)) {
+ loops[nr]->framesdumped++;
+ return realcount;
+ }
+
+ down(&loops[nr]->lock);
+ if (!loops[nr]->buffer) {
+ up(&loops[nr]->lock);
+ return -EINVAL;
+ }
+ if (realcount > loops[nr]->buflength) {
+ realcount = loops[nr]->buflength;
+ printk( VLNAME "To much data! Only %ld bytes used.\n", realcount);
+ }
+
+ copy_from_user(loops[nr]->buffer, buf, realcount);
+ up(&loops[nr]->lock);
+
+ wake_up(&loops[nr]->wait);
+ loops[nr]->frameswrite++;
+
+ return realcount;
+}
+
+static long vloopback_read(struct video_device *v, char *buf, unsigned long count, int noblock)
+{
+ struct vloopback_device *loopdev=(struct vloopback_device *)v;
+ int nr=loopdev->pipenr;
+ unsigned long realcount=count;
+
+ if (loopdev->in) return -EINVAL;
+
+ if (realcount > loops[nr]->buflength) {
+ realcount = loops[nr]->buflength;
+ printk( VLNAME "Not so much data in buffer!\n");
+ }
+
+ interruptible_sleep_on(&loops[nr]->wait);
+
+ down(&loops[nr]->lock);
+ if (!loops[nr]->buffer) {
+ up(&loops[nr]->lock);
+ return 0;
+ }
+ copy_to_user(buf, loops[nr]->buffer, realcount);
+ up(&loops[nr]->lock);
+
+ loops[nr]->framesread++;
+ return realcount;
+}
+
+static int vloopback_mmap(struct video_device *dev, const char *adr, unsigned long size)
+{
+ struct vloopback_device *loopdev=(struct vloopback_device *)dev;
+ int nr=loopdev->pipenr;
+ unsigned long start = (unsigned long)adr;
+ unsigned long page, pos;
+
+ down(&loops[nr]->lock);
+ if (loops[nr]->buffer == NULL) {
+ up(&loops[nr]->lock);
+ return -EINVAL;
+ }
+
+ printk(VLNAME "mmap: %ld (%lX) bytes\n", size, size);
+
+ if (size > (((2 * loops[nr]->buflength) + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1))) {
+ up(&loops[nr]->lock);
+ return -EINVAL;
+ }
+
+ pos = (unsigned long)loops[nr]->buffer;
+ while (size > 0) {
+ page = kvirt_to_pa(pos);
+ if (remap_page_range(start, page, PAGE_SIZE, PAGE_SHARED)) {
+ up(&loops[nr]->lock);
+ return -EAGAIN;
+ }
+ start += PAGE_SIZE;
+ pos += PAGE_SIZE;
+ if (size > PAGE_SIZE)
+ size -= PAGE_SIZE;
+ else
+ size = 0;
+ }
+ up(&loops[nr]->lock);
+
+ return 0;
+}
+
+static int vloopback_ioctl(struct video_device *dev, unsigned int cmd, void *arg)
+{
+ struct vloopback_device *loopdev=(struct vloopback_device *)dev;
+ int nr=loopdev->pipenr;
+
+ switch(cmd)
+ {
+ case VIDIOCGCAP:
+ {
+ struct video_capability b;
+ if (loopdev->in) {
+ sprintf(b.name, "Video loopback %d input",
+ loopdev->pipenr);
+ b.type = 0;
+ } else {
+ sprintf(b.name, "Video loopback %d output",
+ loopdev->pipenr);
+ b.type = VID_TYPE_CAPTURE;
+ }
+ b.channels=1;
+ b.audios=0;
+ b.maxwidth=loops[nr]->width;
+ b.maxheight=loops[nr]->height;
+ b.minwidth=loops[nr]->width;
+ b.minheight=loops[nr]->height;
+ if(copy_to_user(arg, &b, sizeof(b)))
+ return -EFAULT;
+ return 0;
+ }
+ case VIDIOCGCHAN:
+ {
+ struct video_channel v;
+ if(copy_from_user(&v, arg, sizeof(v)))
+ return -EFAULT;
+ if(v.channel!=0)
+ return -EINVAL;
+ v.flags=0;
+ v.tuners=0;
+ v.type = VIDEO_TYPE_CAMERA;
+ strcpy(v.name, "Loopback");
+ if(copy_to_user(arg, &v, sizeof(v)))
+ return -EFAULT;
+ return 0;
+ }
+ case VIDIOCSCHAN:
+ {
+ int v;
+ if(copy_from_user(&v, arg, sizeof(v)))
+ return -EFAULT;
+ if(v!=0)
+ return -EINVAL;
+ return 0;
+ }
+ case VIDIOCGTUNER:
+ {
+ struct video_tuner v;
+ if(copy_from_user(&v, arg, sizeof(v))!=0)
+ return -EFAULT;
+ if(v.tuner)
+ return -EINVAL;
+ strcpy(v.name, "Format");
+ v.rangelow=0;
+ v.rangehigh=0;
+ v.flags=0;
+ v.mode=VIDEO_MODE_AUTO;
+ if(copy_to_user(arg,&v, sizeof(v))!=0)
+ return -EFAULT;
+ return 0;
+ }
+ case VIDIOCGPICT:
+ {
+ struct video_picture p;
+ p.colour=0x8000;
+ p.hue=0x8000;
+ p.brightness=0x8000;
+ p.contrast=0x8000;
+ p.whiteness=0x8000;
+ p.depth=0x8000;
+ p.palette=loops[nr]->palette;
+ if(copy_to_user(arg, &p, sizeof(p)))
+ return -EFAULT;
+ return 0;
+
+ }
+ case VIDIOCSPICT:
+ {
+ struct video_picture p;
+ if(copy_from_user(&p, arg, sizeof(p)))
+ return -EFAULT;
+ if (!loopdev->in) {
+ if (p.palette!=loops[nr]->palette)
+ return -EINVAL;
+ } else
+ loops[nr]->palette=p.palette;
+ return 0;
+ }
+ case VIDIOCSWIN:
+ {
+ struct video_window vw;
+
+ if(copy_from_user(&vw, arg, sizeof(vw)))
+ return -EFAULT;
+ if(vw.flags)
+ return -EINVAL;
+ if(vw.clipcount)
+ return -EINVAL;
+ if (loops[nr]->height==vw.height &&
+ loops[nr]->width==vw.width)
+ return 0;
+ if(!loopdev->in) {
+ return -EINVAL;
+ } else {
+ loops[nr]->height=vw.height;
+ loops[nr]->width=vw.width;
+ /* Make sure nobody is using the buffer while we
+ fool around with it.
+ We are also not allowing changes while
+ somebody using mmap has the output open.
+ */
+ down(&loops[nr]->lock);
+ if (loops[nr]->ropen) {
+ printk(VLNAME "Can't change size while opened for read\n");
+ up(&loops[nr]->lock);
+ return -EINVAL;
+ }
+ if (loops[nr]->buffer)
+ rvfree(loops[nr]->buffer, loops[nr]->buflength);
+ loops[nr]->buflength=vw.width*vw.height*4;
+ loops[nr]->buffer=rvmalloc(loops[nr]->buflength);
+ up(&loops[nr]->lock);
+ }
+ return 0;
+ }
+ case VIDIOCGWIN:
+ {
+ struct video_window vw;
+ vw.x=0;
+ vw.y=0;
+ vw.width=loops[nr]->width;
+ vw.height=loops[nr]->height;
+ vw.chromakey=0;
+ vw.flags=0;
+ vw.clipcount=0;
+ if(copy_to_user(arg, &vw, sizeof(vw)))
+ return -EFAULT;
+ return 0;
+ }
+ case VIDIOCGMBUF:
+ {
+ struct video_mbuf vm;
+
+ if (loopdev->in)
+ return -EINVAL;
+ vm.size=loops[nr]->buflength;
+ vm.frames=1;
+ vm.offsets[0]=0;
+ if(copy_to_user(arg, &vm, sizeof(vm)))
+ return -EFAULT;
+ return 0;
+ }
+ case VIDIOCMCAPTURE:
+ {
+ struct video_mmap vm;
+
+ if (loopdev->in)
+ return -EINVAL;
+ if (!loops[nr]->buffer)
+ return -EINVAL;
+ if (copy_from_user(&vm, arg, sizeof(vm)))
+ return -EFAULT;
+ if (vm.height!=loops[nr]->height ||
+ vm.width!=loops[nr]->width ||
+ vm.format!=loops[nr]->palette) {
+ printk (VLNAME "heigth: %d ioctl: %d\n"
+ VLNAME "width: %d ioctl: %d\n"
+ VLNAME "palette:%d ioctl: %d\n",
+ loops[nr]->height, vm.height,
+ loops[nr]->width, vm.width,
+ loops[nr]->palette, vm.format);
+
+ return -EINVAL;
+ }
+ return 0;
+ }
+ case VIDIOCSYNC:
+ {
+ if (loopdev->in)
+ return -EINVAL;
+ if (!loops[nr]->buffer)
+ return -EINVAL;
+ /* Ok, everything should be alright since the program
+ should have called VIDIOMCAPTURE and we are ready to
+ do the 'capturing' */
+ interruptible_sleep_on(&loops[nr]->wait);
+ loops[nr]->framesread++;
+
+ return 0;
+ }
+ case VIDIOCGUNIT:
+ {
+ struct video_unit vu;
+
+ if (loopdev->in)
+ vu.video=loops[nr]->vloopout->viddev.minor;
+ else
+ vu.video=loops[nr]->vloopin->viddev.minor;
+ vu.vbi=VIDEO_NO_UNIT;
+ vu.radio=VIDEO_NO_UNIT;
+ vu.audio=VIDEO_NO_UNIT;
+ vu.teletext=VIDEO_NO_UNIT;
+ if (copy_to_user(arg, &vu, sizeof(vu)))
+ return -EFAULT;
+ return 0;
+ }
+ case VIDIOCCAPTURE:
+ case VIDIOCGFBUF:
+ case VIDIOCGFREQ:
+ case VIDIOCSFREQ:
+ case VIDIOCGAUDIO:
+ case VIDIOCSAUDIO:
+ return -EINVAL;
+ case VIDIOCKEY:
+ return 0;
+ default:
+ return -ENOIOCTLCMD;
+ }
+ return 0;
+}
+
+static struct video_device vloopback_template=
+{
+ "Video Loopback",
+ VID_TYPE_CAPTURE,
+ 0,
+ vloopback_open,
+ vloopback_close,
+ vloopback_read,
+ vloopback_write,
+ NULL,
+ vloopback_ioctl,
+ vloopback_mmap,
+ vloopback_init_done,
+ NULL,
+ 0,
+ 0
+};
+
+/****************************************************************************
+ * /proc interface
+ * Based on the ov511 driver
+ ****************************************************************************/
+
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
+
+static struct proc_dir_entry *vloopback_proc_entry = NULL;
+extern struct proc_dir_entry *video_proc_entry;
+
+#define YES_NO(x) ((x) ? "yes" : "no")
+
+static int vloopback_read_proc(char *page, char **start, off_t off,
+ int count, int *eof, void *data)
+{
+ char *out=page;
+ int len;
+ struct vloopback_pipe *pipe=data;
+
+ out += sprintf (out, "driver : "VLVER"\n");
+ out += sprintf (out, "input : video%d\n", pipe->vloopin->viddev.minor);
+ out += sprintf (out, "output : video%d\n", pipe->vloopout->viddev.minor);
+ out += sprintf (out, "writing : %s\n", YES_NO (pipe->wopen));
+ if (pipe->wopen) {
+ out += sprintf (out, "written : %ld\n", pipe->frameswrite);
+ out += sprintf (out, "dumped : %ld\n", pipe->framesdumped);
+ out += sprintf (out, "reading : %s\n", YES_NO (pipe->ropen));
+ if (pipe->ropen)
+ out += sprintf (out, "read : %ld\n", pipe->framesread);
+ }
+
+ len = out - page;
+ len -= off;
+ if (len < count) {
+ *eof=1;
+ if (len <= 0) return 0;
+ } else
+ len = count;
+
+ *start = page + off;
+
+ return len;
+}
+
+static int vloopback_write_proc(struct file *file, const char *buffer,
+ unsigned long count, void *data)
+{
+ return -EINVAL;
+}
+
+static void create_proc_vloopback (int nr)
+{
+ char name[16];
+ struct proc_dir_entry *ent;
+
+ if (!vloopback_proc_entry)
+ return;
+
+ sprintf(name, "vloopback%d", nr);
+
+ ent=create_proc_entry(name, S_IFREG | S_IRUGO | S_IWUSR, vloopback_proc_entry);
+
+ if (!ent) {
+ loops[nr]->proc_entry=NULL;
+ return;
+ }
+
+ ent->data = loops[nr];
+ ent->read_proc = vloopback_read_proc;
+ ent->write_proc = vloopback_write_proc;
+ loops[nr]->proc_entry = ent;
+}
+
+static void destroy_proc_vloopback (int nr)
+{
+ char name[16];
+
+ if (!loops[nr]->proc_entry)
+ return;
+
+ sprintf(name, "vloopback%d", nr);
+ remove_proc_entry(name, vloopback_proc_entry);
+ loops[nr]->proc_entry=NULL;
+}
+
+static void proc_vloopback_create(void)
+{
+ if (video_proc_entry == NULL) {
+ printk(VLNAME "Unable to initialise /proc/video/vloopback");
+ return;
+ }
+
+ vloopback_proc_entry=create_proc_entry("vloopback", S_IFDIR, video_proc_entry);
+
+ if (vloopback_proc_entry)
+ vloopback_proc_entry->owner = THIS_MODULE;
+ else
+ printk(VLNAME "Unable to initialise /proc/video/vloopback");
+}
+
+static void proc_vloopback_destroy(void)
+{
+ if (vloopback_proc_entry == NULL)
+ return;
+
+ remove_proc_entry("vloopback", video_proc_entry);
+}
+#endif /* CONFIG_PROC_FS && CONFIG_VIDEO_PROC_FS */
+
+
+/****************************************************************************
+ * init stuff
+ ****************************************************************************/
+
+static int create_pipe(int nr)
+{
+ loops[nr]= kmalloc(sizeof(struct vloopback_pipe), GFP_KERNEL);
+ loops[nr]->vloopin= kmalloc(sizeof(struct vloopback_device), GFP_KERNEL);
+ loops[nr]->vloopout= kmalloc(sizeof(struct vloopback_device), GFP_KERNEL);
+ loops[nr]->vloopin->pipenr=nr;
+ loops[nr]->vloopout->pipenr=nr;
+ loops[nr]->buffer=NULL;
+ loops[nr]->width=0;
+ loops[nr]->height=0;
+ loops[nr]->palette=0;
+ loops[nr]->frameswrite=0;
+ loops[nr]->framesread=0;
+ loops[nr]->framesdumped=0;
+ loops[nr]->wopen=0;
+ loops[nr]->ropen=0;
+ memcpy(loops[nr]->vloopin, &vloopback_template, sizeof(vloopback_template));
+ memcpy(loops[nr]->vloopout, &vloopback_template, sizeof(vloopback_template));
+ loops[nr]->vloopin->in=1;
+ loops[nr]->vloopout->in=0;
+ ((struct video_device *)loops[nr]->vloopin)->type=0;
+ sprintf(((struct video_device *)loops[nr]->vloopin)->name, "Video loopback %d input", nr);
+ ((struct video_device *)loops[nr]->vloopout)->type=VID_TYPE_CAPTURE;
+ sprintf(((struct video_device *)loops[nr]->vloopout)->name, "Video loopback %d output", nr);
+ init_waitqueue_head(&loops[nr]->wait);
+ init_MUTEX(&loops[nr]->lock);
+ if (video_register_device(&loops[nr]->vloopin->viddev, VFL_TYPE_GRABBER)==-1) {
+ kfree(loops[nr]->vloopin);
+ kfree(loops[nr]->vloopout);
+ kfree(loops[nr]);
+ loops[nr]=NULL;
+ printk(VLNAME "error registering device\n");
+ return -ENODEV;
+ }
+ if (video_register_device(&loops[nr]->vloopout->viddev, VFL_TYPE_GRABBER)==-1) {
+ video_unregister_device(&loops[nr]->vloopin->viddev);
+ kfree(loops[nr]->vloopin);
+ kfree(loops[nr]->vloopout);
+ kfree(loops[nr]);
+ loops[nr]=NULL;
+ printk(VLNAME "error registering device\n");
+ return -ENODEV;
+ }
+#if defined(CONFIG_PROC_FS) && defined (CONFIG_VIDEO_PROC_FS)
+ create_proc_vloopback(nr);
+#endif
+ return 0;
+}
+
+MODULE_AUTHOR("J.B. Vreeken (pe1rxq@xxxxxxxxx)");
+MODULE_DESCRIPTION("Video4linux loopback device.");
+MODULE_PARM(pipes, "i");
+MODULE_PARM_DESC(pipes, "Nr of pipes to create (each pipe uses two video devices)");
+
+EXPORT_NO_SYMBOLS;
+
+static int __init vloopback_init(void)
+{
+ int i;
+
+ printk(VLNAME "Video4linux loopback driver v"VLVER"\n");
+ printk(VLNAME "Written by Jeroen Vreeken, 2000 (pe1rxq@xxxxxxxxx)\n");
+
+ if (pipes==-1) pipes=1;
+ if (pipes > MAX_PIPES) {
+ pipes=MAX_PIPES;
+ printk(VLNAME "Nr of pipes is limited to: %d\n", MAX_PIPES);
+ }
+
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
+ proc_vloopback_create();
+#endif
+
+ printk(VLNAME "Registering devices\n");
+ for (i=0; i<pipes; i++) {
+ if (!create_pipe(i)) {
+ printk(VLNAME "Loopback %d registered, input: video%d, output: video%d\n",
+ i, loops[i]->vloopin->viddev.minor, loops[i]->vloopout->viddev.minor);
+ nr_o_pipes=i+1;
+ }
+ }
+ return 0;
+}
+
+static void __exit cleanup_vloopback_module(void)
+{
+ int i;
+
+ printk(VLNAME "Unregistering video4linux loopback devices\n");
+ for (i=0; i<nr_o_pipes; i++) if (loops[i]) {
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
+ destroy_proc_vloopback(i);
+#endif
+ video_unregister_device(&loops[i]->vloopin->viddev);
+ kfree(loops[i]->vloopin);
+ video_unregister_device(&loops[i]->vloopout->viddev);
+ kfree(loops[i]->vloopout);
+ if (loops[i]->buffer) rvfree(loops[i]->buffer, loops[i]->buflength);
+ kfree(loops[i]);
+ }
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS)
+ proc_vloopback_destroy();
+#endif
+ printk(VLNAME "devices unregistered\n");
+}
+
+module_init(vloopback_init);
+module_exit(cleanup_vloopback_module);
