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gerrit-public.fairphone.software / kernel / msm-4.9 / 8c9d26fd55ac7378ad0e2afd2bd122fa060bdaee / . / drivers / staging / tm6000 / tm6000-video.c
blob: 41073ed2cb594f44ad79ef5dab85f93ced7b44dd [file] [log] [blame]
/*
tm6000-video.c - driver for TM5600/TM6000 USB video capture devices
Copyright (C) 2006-2007 Mauro Carvalho Chehab <mchehab@infradead.org>
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 version 2
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/random.h>
#include <linux/version.h>
#include <linux/usb.h>
#include <linux/videodev2.h>
#ifdef CONFIG_VIDEO_V4L1_COMPAT
#include <linux/videodev.h>
#endif
#include <linux/interrupt.h>
#include <linux/kthread.h>
#include <linux/highmem.h>
#include <linux/freezer.h>
#include "tm6000-regs.h"
#include "tm6000.h"
#define BUFFER_TIMEOUT msecs_to_jiffies(2000) /* 2 seconds */
/* Declare static vars that will be used as parameters */
static unsigned int vid_limit = 16; /* Video memory limit, in Mb */
static int video_nr = -1; /* /dev/videoN, -1 for autodetect */
unsigned long tm6000_devused;
/* Debug level */
int tm6000_debug;
/* supported controls */
static struct v4l2_queryctrl tm6000_qctrl[] = {
{
.id = V4L2_CID_BRIGHTNESS,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Brightness",
.minimum = 0,
.maximum = 255,
.step = 1,
.default_value = 54,
.flags = 0,
}, {
.id = V4L2_CID_CONTRAST,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Contrast",
.minimum = 0,
.maximum = 255,
.step = 0x1,
.default_value = 119,
.flags = 0,
}, {
.id = V4L2_CID_SATURATION,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Saturation",
.minimum = 0,
.maximum = 255,
.step = 0x1,
.default_value = 112,
.flags = 0,
}, {
.id = V4L2_CID_HUE,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Hue",
.minimum = -128,
.maximum = 127,
.step = 0x1,
.default_value = 0, //4 ?
.flags = 0,
}
};
static int qctl_regs[ARRAY_SIZE(tm6000_qctrl)];
static struct tm6000_fmt format[] = {
{
.name = "4:2:2, packed, YVY2",
.fourcc = V4L2_PIX_FMT_YUYV,
.depth = 16,
},{
.name = "4:2:2, packed, UYVY",
.fourcc = V4L2_PIX_FMT_UYVY,
.depth = 16,
},{
.name = "A/V + VBI mux packet",
.fourcc = V4L2_PIX_FMT_TM6000,
.depth = 16,
}
};
static LIST_HEAD(tm6000_corelist);
/* ------------------------------------------------------------------
DMA and thread functions
------------------------------------------------------------------*/
#define norm_maxw(a) 720
#define norm_maxh(a) 480
//#define norm_minw(a) norm_maxw(a)
#define norm_minw(a) norm_maxw(a)
#define norm_minh(a) norm_maxh(a)
/*
* video-buf generic routine to get the next available buffer
*/
static int inline get_next_buf (struct tm6000_dmaqueue *dma_q,
struct tm6000_buffer **buf)
{
struct tm6000_core *dev= container_of(dma_q,struct tm6000_core,vidq);
if (list_empty(&dma_q->active)) {
dprintk(dev, V4L2_DEBUG_QUEUE,"No active queue to serve\n");
return 0;
}
*buf = list_entry(dma_q->active.next,
struct tm6000_buffer, vb.queue);
/* Nobody is waiting something to be done, just return */
if (!waitqueue_active(&(*buf)->vb.done)) {
mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
return -1;
}
return 1;
}
/*
* Announces that a buffer were filled and request the next
*/
static void inline buffer_filled (struct tm6000_core *dev,
struct tm6000_buffer *buf)
{
/* Advice that buffer was filled */
dprintk(dev, V4L2_DEBUG_QUEUE, "[%p/%d] wakeup\n",buf,buf->vb.i);
buf->vb.state = STATE_DONE;
buf->vb.field_count++;
do_gettimeofday(&buf->vb.ts);
list_del(&buf->vb.queue);
wake_up(&buf->vb.done);
}
/*
* Macro to allow copying data into the proper memory type
*/
#define bufcpy(buf,out_ptr,in_ptr,size) \
{ \
if (__copy_to_user(out_ptr,in_ptr,size)!=0) \
tm6000_err("copy_to_user failed.\n"); \
}
/*
* Identify the tm5600/6000 buffer header type and properly handles
*/
static int copy_streams(u8 *data, u8 *out_p, unsigned long len,
struct urb *urb, struct tm6000_buffer **buf)
{
struct tm6000_dmaqueue *dma_q = urb->context;
struct tm6000_core *dev= container_of(dma_q,struct tm6000_core,vidq);
u8 *ptr=data, *endp=data+len;
u8 c;
unsigned int cmd, cpysize, pktsize, size, field, block, line, pos=0;
unsigned long header;
int rc=0;
/* FIXME: this is the hardcoded window size
*/
unsigned int linesize=720*2;
//static int last_line=-2;
for (ptr=data; ptr<endp;) {
if (!dev->isoc_ctl.cmd) {
/* Seek for sync */
for (ptr+=3;ptr<endp;ptr++) {
if (*ptr==0x47) {
ptr-=3;
break;
}
}
if (ptr>=endp)
return rc;
/* Get message header */
header=*(unsigned long *)ptr;
ptr+=4;
c=(header>>24) & 0xff;
/* split the header fields */
size = (((header & 0x7e)<<1) -1) *4;
block = (header>>7) & 0xf;
field = (header>>11) & 0x1;
line = (header>>12) & 0x1ff;
cmd = (header>>21) & 0x7;
/* FIXME: Maximum possible line is 511.
* This doesn't seem to be enough for PAL standards
*/
/* Validates header fields */
if(size>TM6000_URB_MSG_LEN)
size=TM6000_URB_MSG_LEN;
if(block>=8)
cmd = TM6000_URB_MSG_ERR;
/* FIXME: Mounts the image as field0+field1
* It should, instead, check if the user selected
* entrelaced or non-entrelaced mode
*/
pos=((line<<1)+field)*linesize+
block*TM6000_URB_MSG_LEN;
/* Don't allow to write out of the buffer */
if (pos+TM6000_URB_MSG_LEN > (*buf)->vb.size)
cmd = TM6000_URB_MSG_ERR;
/* Prints debug info */
dprintk(dev, V4L2_DEBUG_ISOC, "size=%d, num=%d, "
" line=%d, field=%d\n",
size, block, line, field);
dev->isoc_ctl.cmd = cmd;
dev->isoc_ctl.size = size;
dev->isoc_ctl.pos = pos;
dev->isoc_ctl.pktsize = pktsize = TM6000_URB_MSG_LEN;
} else {
cmd = dev->isoc_ctl.cmd;
size= dev->isoc_ctl.size;
pos = dev->isoc_ctl.pos;
pktsize = dev->isoc_ctl.pktsize;
}
cpysize=(endp-ptr>size)?size:endp-ptr;
if (cpysize) {
/* handles each different URB message */
switch(cmd) {
case TM6000_URB_MSG_VIDEO:
/* Fills video buffer */
bufcpy(*buf,&out_p[pos],ptr,cpysize);
break;
}
}
if (cpysize<size) {
/* End of URB packet, but cmd processing is not
* complete. Preserve the state for a next packet
*/
dev->isoc_ctl.pos = pos+cpysize;
dev->isoc_ctl.size= size-cpysize;
dev->isoc_ctl.cmd = cmd;
dev->isoc_ctl.pktsize = pktsize-cpysize;
ptr+=cpysize;
} else {
dev->isoc_ctl.cmd = 0;
ptr+=pktsize;
}
}
return rc;
}
/*
* Identify the tm5600/6000 buffer header type and properly handles
*/
static int copy_multiplexed(u8 *ptr, u8 *out_p, unsigned long len,
struct urb *urb, struct tm6000_buffer **buf)
{
struct tm6000_dmaqueue *dma_q = urb->context;
struct tm6000_core *dev= container_of(dma_q,struct tm6000_core,vidq);
unsigned int pos=dev->isoc_ctl.pos,cpysize;
int rc=1;
while (len>0) {
cpysize=min(len,(*buf)->vb.size-pos);
//printk("Copying %d bytes (max=%lu) from %p to %p[%u]\n",cpysize,(*buf)->vb.size,ptr,out_p,pos);
bufcpy(*buf,&out_p[pos],ptr,cpysize);
pos+=cpysize;
ptr+=cpysize;
len-=cpysize;
if (pos >= (*buf)->vb.size) {
pos=0;
/* Announces that a new buffer were filled */
buffer_filled (dev, *buf);
dprintk(dev, V4L2_DEBUG_QUEUE, "new buffer filled\n");
rc=get_next_buf (dma_q, buf);
if (rc<=0) {
*buf=NULL;
printk(KERN_ERR "tm6000: buffer underrun\n");
break;
}
}
}
dev->isoc_ctl.pos=pos;
return rc;
}
/*
* Controls the isoc copy of each urb packet
*/
static inline int tm6000_isoc_copy(struct urb *urb, struct tm6000_buffer **buf)
{
struct tm6000_dmaqueue *dma_q = urb->context;
struct tm6000_core *dev= container_of(dma_q,struct tm6000_core,vidq);
void *outp=videobuf_to_vmalloc (&((*buf)->vb));
int i, len=0, rc=1;
int size=(*buf)->vb.size;
char *p;
unsigned long copied;
copied=0;
for (i = 0; i < urb->number_of_packets; i++) {
int status = urb->iso_frame_desc[i].status;
char *errmsg = "Unknown";
switch(status) {
case -ENOENT:
errmsg = "unlinked synchronuously";
break;
case -ECONNRESET:
errmsg = "unlinked asynchronuously";
break;
case -ENOSR:
errmsg = "Buffer error (overrun)";
break;
case -EPIPE:
errmsg = "Stalled (device not responding)";
break;
case -EOVERFLOW:
errmsg = "Babble (bad cable?)";
break;
case -EPROTO:
errmsg = "Bit-stuff error (bad cable?)";
break;
case -EILSEQ:
errmsg = "CRC/Timeout (could be anything)";
break;
case -ETIME:
errmsg = "Device does not respond";
break;
}
dprintk(dev, V4L2_DEBUG_QUEUE, "URB status %d [%s].\n",
status, errmsg);
if (status<0)
continue;
len=urb->iso_frame_desc[i].actual_length;
if (len>=TM6000_URB_MSG_LEN) {
p=urb->transfer_buffer + urb->iso_frame_desc[i].offset;
if (!urb->iso_frame_desc[i].status) {
if (((*buf)->fmt->fourcc)==V4L2_PIX_FMT_TM6000) {
rc=copy_multiplexed(p,outp,len,urb,buf);
if (rc<=0)
return rc;
} else {
rc=copy_streams(p,outp,len,urb,buf);
}
}
copied += len;
if (copied>=size)
break;
}
}
if (((*buf)->fmt->fourcc)!=V4L2_PIX_FMT_TM6000) {
buffer_filled (dev, *buf);
dprintk(dev, V4L2_DEBUG_QUEUE, "new buffer filled\n");
}
return rc;
}
/* ------------------------------------------------------------------
URB control
------------------------------------------------------------------*/
/*
* IRQ callback, called by URB callback
*/
static void tm6000_irq_callback(struct urb *urb)
{
struct tm6000_buffer *buf;
struct tm6000_dmaqueue *dma_q = urb->context;
struct tm6000_core *dev= container_of(dma_q,struct tm6000_core,vidq);
int rc,i;
unsigned long flags;
spin_lock_irqsave(&dev->slock,flags);
rc=get_next_buf (dma_q, &buf);
if (rc<=0)
goto ret;
/* Copy data from URB */
rc=tm6000_isoc_copy(urb, &buf);
ret:
/* Reset urb buffers */
for (i = 0; i < urb->number_of_packets; i++) {
urb->iso_frame_desc[i].status = 0;
urb->iso_frame_desc[i].actual_length = 0;
}
urb->status = 0;
if ((urb->status = usb_submit_urb(urb, GFP_ATOMIC))) {
tm6000_err("urb resubmit failed (error=%i)\n",
urb->status);
}
if (rc>=0) {
if (!rc) {
dprintk(dev, V4L2_DEBUG_QUEUE, "No active queue to serve\n");
del_timer(&dma_q->timeout);
} else {
/* Data filled, reset watchdog */
mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
}
}
spin_unlock_irqrestore(&dev->slock,flags);
}
/*
* Stop and Deallocate URBs
*/
static void tm6000_uninit_isoc(struct tm6000_core *dev)
{
struct urb *urb;
int i;
for (i = 0; i < dev->isoc_ctl.num_bufs; i++) {
urb=dev->isoc_ctl.urb[i];
if (urb) {
usb_kill_urb(urb);
usb_unlink_urb(urb);
if (dev->isoc_ctl.transfer_buffer[i]) {
usb_buffer_free(dev->udev,
urb->transfer_buffer_length,
dev->isoc_ctl.transfer_buffer[i],
urb->transfer_dma);
}
usb_free_urb(urb);
dev->isoc_ctl.urb[i] = NULL;
}
dev->isoc_ctl.transfer_buffer[i] = NULL;
}
kfree (dev->isoc_ctl.urb);
kfree (dev->isoc_ctl.transfer_buffer);
dev->isoc_ctl.urb=NULL;
dev->isoc_ctl.transfer_buffer=NULL;
dev->isoc_ctl.num_bufs=0;
}
/*
* Stop video thread - FIXME: Can be easily removed
*/
static void tm6000_stop_thread(struct tm6000_dmaqueue *dma_q)
{
struct tm6000_core *dev= container_of(dma_q,struct tm6000_core,vidq);
tm6000_uninit_isoc(dev);
}
/*
* Allocate URBs and start IRQ
*/
static int tm6000_prepare_isoc(struct tm6000_core *dev,
int max_packets, int num_bufs)
{
struct tm6000_dmaqueue *dma_q = &dev->vidq;
int i;
int sb_size, pipe;
struct urb *urb;
int j, k;
/* De-allocates all pending stuff */
tm6000_uninit_isoc(dev);
dev->isoc_ctl.num_bufs=num_bufs;
dev->isoc_ctl.urb=kmalloc(sizeof(void *)*num_bufs,
GFP_KERNEL);
if (!dev->isoc_ctl.urb) {
tm6000_err("cannot alloc memory for usb buffers\n");
return -ENOMEM;
}
dev->isoc_ctl.transfer_buffer=kmalloc(sizeof(void *)*num_bufs,
GFP_KERNEL);
if (!dev->isoc_ctl.urb) {
tm6000_err("cannot allocate memory for usbtransfer\n");
kfree(dev->isoc_ctl.urb);
return -ENOMEM;
}
dev->isoc_ctl.max_pkt_size=dev->max_isoc_in;
sb_size = max_packets * dev->isoc_ctl.max_pkt_size;
/* allocate urbs and transfer buffers */
for (i = 0; i < dev->isoc_ctl.num_bufs; i++) {
urb = usb_alloc_urb(max_packets, GFP_KERNEL);
if (!urb) {
tm6000_err("cannot alloc isoc_ctl.urb %i\n", i);
tm6000_uninit_isoc(dev);
return -ENOMEM;
}
dev->isoc_ctl.urb[i] = urb;
dev->isoc_ctl.transfer_buffer[i] = usb_buffer_alloc(dev->udev,
sb_size, GFP_KERNEL,
&dev->isoc_ctl.urb[i]->transfer_dma);
if (!dev->isoc_ctl.transfer_buffer[i]) {
tm6000_err ("unable to allocate %i bytes for transfer"
" buffer %i\n", sb_size, i);
tm6000_uninit_isoc(dev);
return -ENOMEM;
}
memset(dev->isoc_ctl.transfer_buffer[i], 0, sb_size);
pipe=usb_rcvisocpipe(dev->udev,
dev->isoc_in->desc.bEndpointAddress &
USB_ENDPOINT_NUMBER_MASK);
usb_fill_int_urb(urb, dev->udev, pipe,
dev->isoc_ctl.transfer_buffer[i],sb_size,
tm6000_irq_callback, dma_q,
dev->isoc_in->desc.bInterval);
urb->number_of_packets = max_packets;
urb->transfer_flags = URB_ISO_ASAP;
k = 0;
for (j = 0; j < max_packets; j++) {
urb->iso_frame_desc[j].offset = k;
urb->iso_frame_desc[j].length =
dev->isoc_ctl.max_pkt_size;
k += dev->isoc_ctl.max_pkt_size;
}
}
return 0;
}
static int tm6000_start_thread( struct tm6000_dmaqueue *dma_q,
struct tm6000_buffer *buf)
{
struct tm6000_core *dev= container_of(dma_q,struct tm6000_core,vidq);
int i,rc;
dma_q->frame=0;
dma_q->ini_jiffies=jiffies;
init_waitqueue_head(&dma_q->wq);
/* submit urbs and enables IRQ */
for (i = 0; i < dev->isoc_ctl.num_bufs; i++) {
rc = usb_submit_urb(dev->isoc_ctl.urb[i], GFP_KERNEL);
if (rc) {
tm6000_err("submit of urb %i failed (error=%i)\n", i,
rc);
tm6000_uninit_isoc(dev);
return rc;
}
}
if (rc<0)
return rc;
return 0;
}
static int restart_video_queue(struct tm6000_dmaqueue *dma_q)
{
struct tm6000_core *dev= container_of(dma_q,struct tm6000_core,vidq);
struct tm6000_buffer *buf, *prev;
struct list_head *item;
dprintk(dev, V4L2_DEBUG_QUEUE, "%s dma_q=0x%08lx\n",
__FUNCTION__,(unsigned long)dma_q);
if (!list_empty(&dma_q->active)) {
buf = list_entry(dma_q->active.next, struct tm6000_buffer, vb.queue);
dprintk(dev, V4L2_DEBUG_QUEUE,
"restart_queue [%p/%d]: restart dma\n", buf, buf->vb.i);
dprintk(dev, V4L2_DEBUG_QUEUE, "Restarting video dma\n");
tm6000_stop_thread(dma_q);
tm6000_start_thread(dma_q, buf);
/* cancel all outstanding capture / vbi requests */
list_for_each(item,&dma_q->active) {
buf = list_entry(item, struct tm6000_buffer, vb.queue);
list_del(&buf->vb.queue);
buf->vb.state = STATE_ERROR;
wake_up(&buf->vb.done);
}
mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
return 0;
}
prev = NULL;
for (;;) {
if (list_empty(&dma_q->queued))
return 0;
buf = list_entry(dma_q->queued.next, struct tm6000_buffer, vb.queue);
if (NULL == prev) {
list_del(&buf->vb.queue);
list_add_tail(&buf->vb.queue,&dma_q->active);
dprintk(dev, V4L2_DEBUG_QUEUE, "Restarting video dma\n");
tm6000_stop_thread(dma_q);
tm6000_start_thread(dma_q, buf);
buf->vb.state = STATE_ACTIVE;
mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
dprintk(dev, V4L2_DEBUG_QUEUE, "[%p/%d] restart_queue -"
" first active\n", buf, buf->vb.i);
} else if (prev->vb.width == buf->vb.width &&
prev->vb.height == buf->vb.height &&
prev->fmt == buf->fmt) {
list_del(&buf->vb.queue);
list_add_tail(&buf->vb.queue,&dma_q->active);
buf->vb.state = STATE_ACTIVE;
dprintk(dev, V4L2_DEBUG_QUEUE, "[%p/%d] restart_queue -"
" move to active\n",buf,buf->vb.i);
} else {
return 0;
}
prev = buf;
}
}
static void tm6000_vid_timeout(unsigned long data)
{
struct tm6000_core *dev = (struct tm6000_core*)data;
struct tm6000_dmaqueue *vidq = &dev->vidq;
struct tm6000_buffer *buf;
unsigned long flags;
spin_lock_irqsave(&dev->slock,flags);
while (!list_empty(&vidq->active)) {
buf = list_entry(vidq->active.next, struct tm6000_buffer,
vb.queue);
list_del(&buf->vb.queue);
buf->vb.state = STATE_ERROR;
wake_up(&buf->vb.done);
dprintk(dev, V4L2_DEBUG_QUEUE, "tm6000/0: [%p/%d] timeout\n",
buf, buf->vb.i);
}
restart_video_queue(vidq);
spin_unlock_irqrestore(&dev->slock,flags);
}
/* ------------------------------------------------------------------
Videobuf operations
------------------------------------------------------------------*/
static int
buffer_setup(struct videobuf_queue *vq, unsigned int *count, unsigned int *size)
{
struct tm6000_fh *fh = vq->priv_data;
*size = fh->fmt->depth * fh->width * fh->height >> 3;
if (0 == *count)
*count = 32;
while (*size * *count > vid_limit * 1024 * 1024)
(*count)--;
return 0;
}
static void free_buffer(struct videobuf_queue *vq, struct tm6000_buffer *buf)
{
if (in_interrupt())
BUG();
videobuf_waiton(&buf->vb,0,0);
videobuf_vmalloc_free(&buf->vb);
buf->vb.state = STATE_NEEDS_INIT;
}
static int
buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
enum v4l2_field field)
{
struct tm6000_fh *fh = vq->priv_data;
struct tm6000_buffer *buf = container_of(vb,struct tm6000_buffer,vb);
struct tm6000_core *dev = fh->dev;
int rc=0, urbsize, urb_init=0;
BUG_ON(NULL == fh->fmt);
if (fh->width < norm_minw(core) || fh->width > norm_maxw(core) ||
fh->height < norm_minh(core) || fh->height > norm_maxh(core)) {
dprintk(dev, V4L2_DEBUG_QUEUE, "Window size (%dx%d) is out of "
"supported range\n", fh->width, fh->height);
dprintk(dev, V4L2_DEBUG_QUEUE, "Valid range is from (%dx%d) to "
"(%dx%d)\n", norm_minw(core), norm_minh(core),
norm_maxw(core),norm_maxh(core));
return -EINVAL;
}
/* FIXME: It assumes depth=2 */
/* The only currently supported format is 16 bits/pixel */
buf->vb.size = fh->fmt->depth*fh->width*fh->height >> 3;
if (0 != buf->vb.baddr && buf->vb.bsize < buf->vb.size)
return -EINVAL;
if (buf->fmt != fh->fmt ||
buf->vb.width != fh->width ||
buf->vb.height != fh->height ||
buf->vb.field != field) {
buf->fmt = fh->fmt;
buf->vb.width = fh->width;
buf->vb.height = fh->height;
buf->vb.field = field;
buf->vb.state = STATE_NEEDS_INIT;
}
if (STATE_NEEDS_INIT == buf->vb.state) {
if (0 != (rc = videobuf_iolock(vq,&buf->vb,NULL)))
goto fail;
urb_init=1;
}
if (!dev->isoc_ctl.num_bufs)
urb_init=1;
if (urb_init) {
/* Should allocate/request at least h
res x v res x 2 bytes/pixel */
urbsize=(buf->vb.size+dev->max_isoc_in-1)/dev->max_isoc_in;
/* Hack to allocate memory for Video + Audio */
/* FIXME: should also consider header ovehead of
4 bytes/180 bytes */
urbsize+=((48000*4+24)/25+dev->max_isoc_in-1)/dev->max_isoc_in;
dprintk(dev, V4L2_DEBUG_QUEUE, "Allocating %d packets to handle "
"%lu size\n", urbsize,buf->vb.size);
rc = tm6000_prepare_isoc(dev, urbsize, 2);
if (rc<0)
goto fail;
}
buf->vb.state = STATE_PREPARED;
return 0;
fail:
free_buffer(vq,buf);
return rc;
}
static void
buffer_queue(struct videobuf_queue *vq, struct videobuf_buffer *vb)
{
struct tm6000_buffer *buf = container_of(vb,struct tm6000_buffer,vb);
struct tm6000_fh *fh = vq->priv_data;
struct tm6000_core *dev = fh->dev;
struct tm6000_dmaqueue *vidq = &dev->vidq;
struct tm6000_buffer *prev;
if (!list_empty(&vidq->queued)) {
list_add_tail(&buf->vb.queue,&vidq->queued);
buf->vb.state = STATE_QUEUED;
dprintk(dev, V4L2_DEBUG_QUEUE, "[%p/%d] buffer_queue - "
"append to queued\n", buf, buf->vb.i);
} else if (list_empty(&vidq->active)) {
list_add_tail(&buf->vb.queue,&vidq->active);
buf->vb.state = STATE_ACTIVE;
mod_timer(&vidq->timeout, jiffies+BUFFER_TIMEOUT);
dprintk(dev, V4L2_DEBUG_QUEUE, "[%p/%d] buffer_queue - "
"first active\n", buf, buf->vb.i);
tm6000_start_thread(vidq, buf);
} else {
prev = list_entry(vidq->active.prev, struct tm6000_buffer, vb.queue);
if (prev->vb.width == buf->vb.width &&
prev->vb.height == buf->vb.height &&
prev->fmt == buf->fmt) {
list_add_tail(&buf->vb.queue,&vidq->active);
buf->vb.state = STATE_ACTIVE;
dprintk(dev, V4L2_DEBUG_QUEUE, "[%p/%d] buffer_queue -"
" append to active\n", buf, buf->vb.i);
} else {
list_add_tail(&buf->vb.queue,&vidq->queued);
buf->vb.state = STATE_QUEUED;
dprintk(dev, V4L2_DEBUG_QUEUE, "[%p/%d] buffer_queue -"
" first queued\n", buf, buf->vb.i);
}
}
}
static void buffer_release(struct videobuf_queue *vq, struct videobuf_buffer *vb)
{
struct tm6000_buffer *buf = container_of(vb,struct tm6000_buffer,vb);
struct tm6000_fh *fh = vq->priv_data;
struct tm6000_core *dev = (struct tm6000_core*)fh->dev;
struct tm6000_dmaqueue *vidq = &dev->vidq;
tm6000_stop_thread(vidq);
free_buffer(vq,buf);
}
static struct videobuf_queue_ops tm6000_video_qops = {
.buf_setup = buffer_setup,
.buf_prepare = buffer_prepare,
.buf_queue = buffer_queue,
.buf_release = buffer_release,
};
/* ------------------------------------------------------------------
IOCTL handling
------------------------------------------------------------------*/
static int res_get(struct tm6000_core *dev, struct tm6000_fh *fh)
{
/* is it free? */
mutex_lock(&dev->lock);
if (dev->resources) {
/* no, someone else uses it */
mutex_unlock(&dev->lock);
return 0;
}
/* it's free, grab it */
dev->resources =1;
dprintk(dev, V4L2_DEBUG_RES_LOCK, "res: get\n");
mutex_unlock(&dev->lock);
return 1;
}
static int res_locked(struct tm6000_core *dev)
{
return (dev->resources);
}
static void res_free(struct tm6000_core *dev, struct tm6000_fh *fh)
{
mutex_lock(&dev->lock);
dev->resources = 0;
dprintk(dev, V4L2_DEBUG_RES_LOCK, "res: put\n");
mutex_unlock(&dev->lock);
}
/* ------------------------------------------------------------------
IOCTL vidioc handling
------------------------------------------------------------------*/
static int vidioc_querycap (struct file *file, void *priv,
struct v4l2_capability *cap)
{
// struct tm6000_core *dev = ((struct tm6000_fh *)priv)->dev;
strlcpy(cap->driver, "tm6000", sizeof(cap->driver));
strlcpy(cap->card,"Trident TVMaster TM5600/6000", sizeof(cap->card));
// strlcpy(cap->bus_info, dev->udev->dev.bus_id, sizeof(cap->bus_info));
cap->version = TM6000_VERSION;
cap->capabilities = V4L2_CAP_VIDEO_CAPTURE |
V4L2_CAP_STREAMING |
V4L2_CAP_TUNER |
V4L2_CAP_READWRITE;
return 0;
}
static int vidioc_enum_fmt_cap (struct file *file, void *priv,
struct v4l2_fmtdesc *f)
{
if (unlikely(f->index >= ARRAY_SIZE(format)))
return -EINVAL;
strlcpy(f->description,format[f->index].name,sizeof(f->description));
f->pixelformat = format[f->index].fourcc;
return 0;
}
static int vidioc_g_fmt_cap (struct file *file, void *priv,
struct v4l2_format *f)
{
struct tm6000_fh *fh=priv;
f->fmt.pix.width = fh->width;
f->fmt.pix.height = fh->height;
f->fmt.pix.field = fh->vb_vidq.field;
f->fmt.pix.pixelformat = fh->fmt->fourcc;
f->fmt.pix.bytesperline =
(f->fmt.pix.width * fh->fmt->depth) >> 3;
f->fmt.pix.sizeimage =
f->fmt.pix.height * f->fmt.pix.bytesperline;
return (0);
}
static struct tm6000_fmt* format_by_fourcc(unsigned int fourcc)
{
unsigned int i;
for (i = 0; i < ARRAY_SIZE(format); i++)
if (format[i].fourcc == fourcc)
return format+i;
return NULL;
}
static int vidioc_try_fmt_cap (struct file *file, void *priv,
struct v4l2_format *f)
{
struct tm6000_core *dev = ((struct tm6000_fh *)priv)->dev;
struct tm6000_fmt *fmt;
enum v4l2_field field;
fmt = format_by_fourcc(f->fmt.pix.pixelformat);
if (NULL == fmt) {
dprintk(dev, V4L2_DEBUG_IOCTL_ARG, "Fourcc format (0x%08x)"
" invalid.\n", f->fmt.pix.pixelformat);
return -EINVAL;
}
field = f->fmt.pix.field;
if (field == V4L2_FIELD_ANY) {
// field=V4L2_FIELD_INTERLACED;
field=V4L2_FIELD_SEQ_TB;
} else if (V4L2_FIELD_INTERLACED != field) {
dprintk(dev, V4L2_DEBUG_IOCTL_ARG, "Field type invalid.\n");
return -EINVAL;
}
if (f->fmt.pix.width < norm_minw(core))
f->fmt.pix.width = norm_minw(core);
if (f->fmt.pix.width > norm_maxw(core))
f->fmt.pix.width = norm_maxw(core);
if (f->fmt.pix.height < norm_minh(core))
f->fmt.pix.height = norm_minh(core);
if (f->fmt.pix.height > norm_maxh(core))
f->fmt.pix.height = norm_maxh(core);
f->fmt.pix.width &= ~0x01;
f->fmt.pix.field = field;
f->fmt.pix.bytesperline =
(f->fmt.pix.width * fmt->depth) >> 3;
f->fmt.pix.sizeimage =
f->fmt.pix.height * f->fmt.pix.bytesperline;
return 0;
}
/*FIXME: This seems to be generic enough to be at videodev2 */
static int vidioc_s_fmt_cap (struct file *file, void *priv,
struct v4l2_format *f)
{
struct tm6000_fh *fh=priv;
struct tm6000_core *dev = fh->dev;
int ret = vidioc_try_fmt_cap(file,fh,f);
if (ret < 0)
return (ret);
fh->fmt = format_by_fourcc(f->fmt.pix.pixelformat);
fh->width = f->fmt.pix.width;
fh->height = f->fmt.pix.height;
fh->vb_vidq.field = f->fmt.pix.field;
fh->type = f->type;
dev->fourcc = f->fmt.pix.pixelformat;
tm6000_set_fourcc_format(dev);
return (0);
}
static int vidioc_reqbufs (struct file *file, void *priv,
struct v4l2_requestbuffers *p)
{
struct tm6000_fh *fh=priv;
return (videobuf_reqbufs(&fh->vb_vidq, p));
}
static int vidioc_querybuf (struct file *file, void *priv,
struct v4l2_buffer *p)
{
struct tm6000_fh *fh=priv;
return (videobuf_querybuf(&fh->vb_vidq, p));
}
static int vidioc_qbuf (struct file *file, void *priv, struct v4l2_buffer *p)
{
struct tm6000_fh *fh=priv;
return (videobuf_qbuf(&fh->vb_vidq, p));
}
static int vidioc_dqbuf (struct file *file, void *priv, struct v4l2_buffer *p)
{
struct tm6000_fh *fh=priv;
return (videobuf_dqbuf(&fh->vb_vidq, p,
file->f_flags & O_NONBLOCK));
}
#ifdef CONFIG_VIDEO_V4L1_COMPAT
static int vidiocgmbuf (struct file *file, void *priv, struct video_mbuf *mbuf)
{
struct tm6000_fh *fh=priv;
return videobuf_cgmbuf (&fh->vb_vidq, mbuf, 8);
}
#endif
static int vidioc_streamon(struct file *file, void *priv, enum v4l2_buf_type i)
{
struct tm6000_fh *fh=priv;
struct tm6000_core *dev = fh->dev;
if (fh->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
return -EINVAL;
if (i != fh->type)
return -EINVAL;
if (!res_get(dev,fh))
return -EBUSY;
return (videobuf_streamon(&fh->vb_vidq));
}
static int vidioc_streamoff(struct file *file, void *priv, enum v4l2_buf_type i)
{
struct tm6000_fh *fh=priv;
struct tm6000_core *dev = fh->dev;
if (fh->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
return -EINVAL;
if (i != fh->type)
return -EINVAL;
videobuf_streamoff(&fh->vb_vidq);
res_free(dev,fh);
return (0);
}
static int vidioc_s_std (struct file *file, void *priv, v4l2_std_id *norm)
{
int rc=0;
struct tm6000_fh *fh=priv;
struct tm6000_core *dev = fh->dev;
rc=tm6000_set_standard (dev, norm);
if (rc<0)
return rc;
tm6000_i2c_call_clients(dev, VIDIOC_S_STD, &dev->norm);
return 0;
}
static int vidioc_enum_input (struct file *file, void *priv,
struct v4l2_input *inp)
{
switch (inp->index) {
case TM6000_INPUT_TV:
inp->type = V4L2_INPUT_TYPE_TUNER;
strcpy(inp->name,"Television");
break;
case TM6000_INPUT_COMPOSITE:
inp->type = V4L2_INPUT_TYPE_CAMERA;
strcpy(inp->name,"Composite");
break;
case TM6000_INPUT_SVIDEO:
inp->type = V4L2_INPUT_TYPE_CAMERA;
strcpy(inp->name,"S-Video");
break;
default:
return -EINVAL;
}
inp->std = TM6000_STD;
return 0;
}
static int vidioc_g_input (struct file *file, void *priv, unsigned int *i)
{
struct tm6000_fh *fh=priv;
struct tm6000_core *dev = fh->dev;
*i=dev->input;
return 0;
}
static int vidioc_s_input (struct file *file, void *priv, unsigned int i)
{
struct tm6000_fh *fh=priv;
struct tm6000_core *dev = fh->dev;
int rc=0;
char buf[1];
switch (i) {
case TM6000_INPUT_TV:
dev->input=i;
*buf=0;
break;
case TM6000_INPUT_COMPOSITE:
case TM6000_INPUT_SVIDEO:
dev->input=i;
*buf=1;
break;
default:
return -EINVAL;
}
rc=tm6000_read_write_usb (dev, USB_DIR_OUT | USB_TYPE_VENDOR,
REQ_03_SET_GET_MCU_PIN, 0x03, 1, buf, 1);
if (!rc) {
dev->input=i;
rc=vidioc_s_std (file, priv, &dev->vfd.current_norm);
}
return (rc);
}
/* --- controls ---------------------------------------------- */
static int vidioc_queryctrl (struct file *file, void *priv,
struct v4l2_queryctrl *qc)
{
int i;
for (i = 0; i < ARRAY_SIZE(tm6000_qctrl); i++)
if (qc->id && qc->id == tm6000_qctrl[i].id) {
memcpy(qc, &(tm6000_qctrl[i]),
sizeof(*qc));
return (0);
}
return -EINVAL;
}
static int vidioc_g_ctrl (struct file *file, void *priv,
struct v4l2_control *ctrl)
{
struct tm6000_fh *fh=priv;
struct tm6000_core *dev = fh->dev;
int val;
/* FIXME: Probably, those won't work! Maybe we need shadow regs */
switch (ctrl->id) {
case V4L2_CID_CONTRAST:
val=tm6000_get_reg (dev, REQ_07_SET_GET_AVREG, 0x08, 0);
break;
case V4L2_CID_BRIGHTNESS:
val=tm6000_get_reg (dev, REQ_07_SET_GET_AVREG, 0x09, 0);
return 0;
case V4L2_CID_SATURATION:
val=tm6000_get_reg (dev, REQ_07_SET_GET_AVREG, 0x0a, 0);
return 0;
case V4L2_CID_HUE:
val=tm6000_get_reg (dev, REQ_07_SET_GET_AVREG, 0x0b, 0);
return 0;
default:
return -EINVAL;
}
if (val<0)
return val;
ctrl->value=val;
return 0;
}
static int vidioc_s_ctrl (struct file *file, void *priv,
struct v4l2_control *ctrl)
{
struct tm6000_fh *fh =priv;
struct tm6000_core *dev = fh->dev;
u8 val=ctrl->value;
switch (ctrl->id) {
case V4L2_CID_CONTRAST:
tm6000_set_reg (dev, REQ_07_SET_GET_AVREG, 0x08, val);
return 0;
case V4L2_CID_BRIGHTNESS:
tm6000_set_reg (dev, REQ_07_SET_GET_AVREG, 0x09, val);
return 0;
case V4L2_CID_SATURATION:
tm6000_set_reg (dev, REQ_07_SET_GET_AVREG, 0x0a, val);
return 0;
case V4L2_CID_HUE:
tm6000_set_reg (dev, REQ_07_SET_GET_AVREG, 0x0b, val);
return 0;
}
return -EINVAL;
}
static int vidioc_g_tuner (struct file *file, void *priv,
struct v4l2_tuner *t)
{
struct tm6000_fh *fh =priv;
struct tm6000_core *dev = fh->dev;
if (unlikely(UNSET == dev->tuner_type))
return -EINVAL;
if (0 != t->index)
return -EINVAL;
strcpy(t->name, "Television");
t->type = V4L2_TUNER_ANALOG_TV;
t->capability = V4L2_TUNER_CAP_NORM;
t->rangehigh = 0xffffffffUL;
t->rxsubchans = V4L2_TUNER_SUB_MONO;
return 0;
}
static int vidioc_s_tuner (struct file *file, void *priv,
struct v4l2_tuner *t)
{
struct tm6000_fh *fh =priv;
struct tm6000_core *dev = fh->dev;
if (UNSET == dev->tuner_type)
return -EINVAL;
if (0 != t->index)
return -EINVAL;
return 0;
}
static int vidioc_g_frequency (struct file *file, void *priv,
struct v4l2_frequency *f)
{
struct tm6000_fh *fh =priv;
struct tm6000_core *dev = fh->dev;
if (unlikely(UNSET == dev->tuner_type))
return -EINVAL;
f->type = V4L2_TUNER_ANALOG_TV;
f->frequency = dev->freq;
tm6000_i2c_call_clients(dev,VIDIOC_G_FREQUENCY,f);
return 0;
}
static int vidioc_s_frequency (struct file *file, void *priv,
struct v4l2_frequency *f)
{
struct tm6000_fh *fh =priv;
struct tm6000_core *dev = fh->dev;
if (unlikely(f->type != V4L2_TUNER_ANALOG_TV))
return -EINVAL;
if (unlikely(UNSET == dev->tuner_type))
return -EINVAL;
if (unlikely(f->tuner != 0))
return -EINVAL;
// mutex_lock(&dev->lock);
dev->freq = f->frequency;
tm6000_i2c_call_clients(dev,VIDIOC_S_FREQUENCY,f);
// mutex_unlock(&dev->lock);
return 0;
}
/* ------------------------------------------------------------------
File operations for the device
------------------------------------------------------------------*/
static int tm6000_open(struct inode *inode, struct file *file)
{
int minor = iminor(inode);
struct tm6000_core *h,*dev = NULL;
struct tm6000_fh *fh;
struct list_head *list;
enum v4l2_buf_type type = 0;
int i,rc;
dprintk(dev, V4L2_DEBUG_OPEN, "tm6000: open called "
"(minor=%d)\n",minor);
list_for_each(list,&tm6000_corelist) {
h = list_entry(list, struct tm6000_core, tm6000_corelist);
if (h->vfd.minor == minor) {
dev = h;
type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
}
}
if (NULL == dev)
return -ENODEV;
/* If more than one user, mutex should be added */
dev->users++;
dprintk(dev, V4L2_DEBUG_OPEN, "open minor=%d type=%s users=%d\n",
minor,v4l2_type_names[type],dev->users);
/* allocate + initialize per filehandle data */
fh = kzalloc(sizeof(*fh),GFP_KERNEL);
if (NULL == fh) {
dev->users--;
return -ENOMEM;
}
file->private_data = fh;
fh->dev = dev;
fh->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
dev->fourcc = format[0].fourcc;
fh->fmt = format_by_fourcc(dev->fourcc);
fh->width = norm_maxw();
fh->height = norm_maxh();
dprintk(dev, V4L2_DEBUG_OPEN, "Open: fh=0x%08lx, dev=0x%08lx, "
"dev->vidq=0x%08lx\n",
(unsigned long)fh,(unsigned long)dev,(unsigned long)&dev->vidq);
dprintk(dev, V4L2_DEBUG_OPEN, "Open: list_empty "
"queued=%d\n",list_empty(&dev->vidq.queued));
dprintk(dev, V4L2_DEBUG_OPEN, "Open: list_empty "
"active=%d\n",list_empty(&dev->vidq.active));
/* initialize hardware on analog mode */
if (dev->mode!=TM6000_MODE_ANALOG) {
rc=tm6000_init_analog_mode (dev);
if (rc<0)
return rc;
/* Put all controls at a sane state */
for (i = 0; i < ARRAY_SIZE(tm6000_qctrl); i++)
qctl_regs[i] =tm6000_qctrl[i].default_value;
dev->mode=TM6000_MODE_ANALOG;
}
videobuf_queue_vmalloc_init(&fh->vb_vidq, &tm6000_video_qops,
NULL, &dev->slock,
fh->type,
V4L2_FIELD_INTERLACED,
sizeof(struct tm6000_buffer),fh);
return 0;
}
static ssize_t
tm6000_read(struct file *file, char __user *data, size_t count, loff_t *pos)
{
struct tm6000_fh *fh = file->private_data;
if (fh->type==V4L2_BUF_TYPE_VIDEO_CAPTURE) {
if (res_locked(fh->dev))
return -EBUSY;
return videobuf_read_stream(&fh->vb_vidq, data, count, pos, 0,
file->f_flags & O_NONBLOCK);
}
return 0;
}
static unsigned int
tm6000_poll(struct file *file, struct poll_table_struct *wait)
{
struct tm6000_fh *fh = file->private_data;
struct tm6000_buffer *buf;
if (V4L2_BUF_TYPE_VIDEO_CAPTURE != fh->type)
return POLLERR;
if (res_get(fh->dev,fh)) {
/* streaming capture */
if (list_empty(&fh->vb_vidq.stream))
return POLLERR;
buf = list_entry(fh->vb_vidq.stream.next,struct tm6000_buffer,vb.stream);
} else {
/* read() capture */
buf = (struct tm6000_buffer*)fh->vb_vidq.read_buf;
if (NULL == buf)
return POLLERR;
}
poll_wait(file, &buf->vb.done, wait);
if (buf->vb.state == STATE_DONE ||
buf->vb.state == STATE_ERROR)
return POLLIN|POLLRDNORM;
return 0;
}
static int tm6000_release(struct inode *inode, struct file *file)
{
struct tm6000_fh *fh = file->private_data;
struct tm6000_core *dev = fh->dev;
struct tm6000_dmaqueue *vidq = &dev->vidq;
int minor = iminor(inode);
tm6000_stop_thread(vidq);
videobuf_mmap_free(&fh->vb_vidq);
kfree (fh);
dprintk(dev, V4L2_DEBUG_OPEN, "tm6000: close called (minor=%d, users=%d)\n",minor,dev->users);
return 0;
}
static int tm6000_mmap(struct file *file, struct vm_area_struct * vma)
{
struct tm6000_fh *fh = file->private_data;
int ret;
ret=videobuf_mmap_mapper(&fh->vb_vidq, vma);
return ret;
}
static struct file_operations tm6000_fops = {
.owner = THIS_MODULE,
.open = tm6000_open,
.release = tm6000_release,
.ioctl = video_ioctl2, /* V4L2 ioctl handler */
.read = tm6000_read,
.poll = tm6000_poll,
.mmap = tm6000_mmap,
.llseek = no_llseek,
};
static struct video_device tm6000_template = {
.name = "tm6000",
.type = VID_TYPE_CAPTURE,
.fops = &tm6000_fops,
.minor = -1,
.release = video_device_release,
.vidioc_querycap = vidioc_querycap,
.vidioc_enum_fmt_cap = vidioc_enum_fmt_cap,
.vidioc_g_fmt_cap = vidioc_g_fmt_cap,
.vidioc_try_fmt_cap = vidioc_try_fmt_cap,
.vidioc_s_fmt_cap = vidioc_s_fmt_cap,
.vidioc_s_std = vidioc_s_std,
.vidioc_enum_input = vidioc_enum_input,
.vidioc_g_input = vidioc_g_input,
.vidioc_s_input = vidioc_s_input,
.vidioc_queryctrl = vidioc_queryctrl,
.vidioc_g_ctrl = vidioc_g_ctrl,
.vidioc_s_ctrl = vidioc_s_ctrl,
.vidioc_g_tuner = vidioc_g_tuner,
.vidioc_s_tuner = vidioc_s_tuner,
.vidioc_g_frequency = vidioc_g_frequency,
.vidioc_s_frequency = vidioc_s_frequency,
.vidioc_streamon = vidioc_streamon,
.vidioc_streamoff = vidioc_streamoff,
.vidioc_reqbufs = vidioc_reqbufs,
.vidioc_querybuf = vidioc_querybuf,
.vidioc_qbuf = vidioc_qbuf,
.vidioc_dqbuf = vidioc_dqbuf,
#ifdef CONFIG_VIDEO_V4L1_COMPAT
.vidiocgmbuf = vidiocgmbuf,
#endif
.tvnorms = TM6000_STD,
.current_norm = V4L2_STD_NTSC_M,
};
/* -----------------------------------------------------------------
Initialization and module stuff
------------------------------------------------------------------*/
int tm6000_v4l2_register(struct tm6000_core *dev)
{
int ret;
list_add_tail(&dev->tm6000_corelist,&tm6000_corelist);
/* init video dma queues */
INIT_LIST_HEAD(&dev->vidq.active);
INIT_LIST_HEAD(&dev->vidq.queued);
dev->vidq.timeout.function = tm6000_vid_timeout;
dev->vidq.timeout.data = (unsigned long)dev;
init_timer(&dev->vidq.timeout);
memcpy (&dev->vfd, &tm6000_template, sizeof(dev->vfd));
dev->vfd.debug=tm6000_debug;
ret = video_register_device(&dev->vfd, VFL_TYPE_GRABBER, video_nr);
printk(KERN_INFO "Trident TVMaster TM5600/TM6000 USB2 board (Load status: %d)\n", ret);
return ret;
}
int tm6000_v4l2_unregister(struct tm6000_core *dev)
{
struct tm6000_core *h;
struct list_head *pos, *tmp;
video_unregister_device(&dev->vfd);
list_for_each_safe(pos, tmp, &tm6000_corelist) {
h = list_entry(pos, struct tm6000_core, tm6000_corelist);
if (h == dev) {
list_del(pos);
}
}
return 0;
}
int tm6000_v4l2_exit(void)
{
return 0;
}
module_param(video_nr, int, 0);
MODULE_PARM_DESC(video_nr,"Allow changing video device number");
module_param_named (debug, tm6000_debug, int, 0444);
MODULE_PARM_DESC(debug,"activates debug info");
module_param(vid_limit,int,0644);
MODULE_PARM_DESC(vid_limit,"capture memory limit in megabytes");