1
linux/drivers/media/video/videobuf-core.c
Mauro Carvalho Chehab e2c77314c9 V4L/DVB (6759): CodingStyle fixes
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-01-25 19:03:22 -02:00

1088 lines
24 KiB
C

/*
* generic helper functions for handling video4linux capture buffers
*
* (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org>
*
* Highly based on video-buf written originally by:
* (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
* (c) 2006 Mauro Carvalho Chehab, <mchehab@infradead.org>
* (c) 2006 Ted Walther and John Sokol
*
* 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
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <media/videobuf-core.h>
#define MAGIC_BUFFER 0x20070728
#define MAGIC_CHECK(is, should) do { \
if (unlikely((is) != (should))) { \
printk(KERN_ERR "magic mismatch: %x (expected %x)\n", is, should); \
BUG(); } } while (0)
static int debug;
module_param(debug, int, 0644);
MODULE_DESCRIPTION("helper module to manage video4linux buffers");
MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>");
MODULE_LICENSE("GPL");
#define dprintk(level, fmt, arg...) do { \
if (debug >= level) \
printk(KERN_DEBUG "vbuf: " fmt , ## arg); } while (0)
/* --------------------------------------------------------------------- */
#define CALL(q, f, arg...) \
((q->int_ops->f) ? q->int_ops->f(arg) : 0)
void *videobuf_alloc(struct videobuf_queue *q)
{
struct videobuf_buffer *vb;
BUG_ON(q->msize < sizeof(*vb));
if (!q->int_ops || !q->int_ops->alloc) {
printk(KERN_ERR "No specific ops defined!\n");
BUG();
}
vb = q->int_ops->alloc(q->msize);
if (NULL != vb) {
init_waitqueue_head(&vb->done);
vb->magic = MAGIC_BUFFER;
}
return vb;
}
int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
{
int retval = 0;
DECLARE_WAITQUEUE(wait, current);
MAGIC_CHECK(vb->magic, MAGIC_BUFFER);
add_wait_queue(&vb->done, &wait);
while (vb->state == VIDEOBUF_ACTIVE || vb->state == VIDEOBUF_QUEUED) {
if (non_blocking) {
retval = -EAGAIN;
break;
}
set_current_state(intr ? TASK_INTERRUPTIBLE
: TASK_UNINTERRUPTIBLE);
if (vb->state == VIDEOBUF_ACTIVE ||
vb->state == VIDEOBUF_QUEUED)
schedule();
set_current_state(TASK_RUNNING);
if (intr && signal_pending(current)) {
dprintk(1, "buffer waiton: -EINTR\n");
retval = -EINTR;
break;
}
}
remove_wait_queue(&vb->done, &wait);
return retval;
}
int videobuf_iolock(struct videobuf_queue *q, struct videobuf_buffer *vb,
struct v4l2_framebuffer *fbuf)
{
MAGIC_CHECK(vb->magic, MAGIC_BUFFER);
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
/* FIXME: This is required to avoid OOPS on some cases,
since mmap_mapper() method should be called before _iolock.
On some cases, the mmap_mapper() is called only after scheduling.
However, this way is just too dirty! Better to wait for some event.
*/
schedule_timeout(HZ);
return CALL(q, iolock, q, vb, fbuf);
}
/* --------------------------------------------------------------------- */
void videobuf_queue_core_init(struct videobuf_queue *q,
struct videobuf_queue_ops *ops,
void *dev,
spinlock_t *irqlock,
enum v4l2_buf_type type,
enum v4l2_field field,
unsigned int msize,
void *priv,
struct videobuf_qtype_ops *int_ops)
{
memset(q, 0, sizeof(*q));
q->irqlock = irqlock;
q->dev = dev;
q->type = type;
q->field = field;
q->msize = msize;
q->ops = ops;
q->priv_data = priv;
q->int_ops = int_ops;
/* All buffer operations are mandatory */
BUG_ON(!q->ops->buf_setup);
BUG_ON(!q->ops->buf_prepare);
BUG_ON(!q->ops->buf_queue);
BUG_ON(!q->ops->buf_release);
/* Having implementations for abstract methods are mandatory */
BUG_ON(!q->int_ops);
mutex_init(&q->lock);
INIT_LIST_HEAD(&q->stream);
}
/* Locking: Only usage in bttv unsafe find way to remove */
int videobuf_queue_is_busy(struct videobuf_queue *q)
{
int i;
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
if (q->streaming) {
dprintk(1, "busy: streaming active\n");
return 1;
}
if (q->reading) {
dprintk(1, "busy: pending read #1\n");
return 1;
}
if (q->read_buf) {
dprintk(1, "busy: pending read #2\n");
return 1;
}
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
if (q->bufs[i]->map) {
dprintk(1, "busy: buffer #%d mapped\n", i);
return 1;
}
if (q->bufs[i]->state == VIDEOBUF_QUEUED) {
dprintk(1, "busy: buffer #%d queued\n", i);
return 1;
}
if (q->bufs[i]->state == VIDEOBUF_ACTIVE) {
dprintk(1, "busy: buffer #%d avtive\n", i);
return 1;
}
}
return 0;
}
/* Locking: Caller holds q->lock */
void videobuf_queue_cancel(struct videobuf_queue *q)
{
unsigned long flags = 0;
int i;
/* remove queued buffers from list */
if (q->irqlock)
spin_lock_irqsave(q->irqlock, flags);
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
if (q->bufs[i]->state == VIDEOBUF_QUEUED) {
list_del(&q->bufs[i]->queue);
q->bufs[i]->state = VIDEOBUF_ERROR;
}
}
if (q->irqlock)
spin_unlock_irqrestore(q->irqlock, flags);
/* free all buffers + clear queue */
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
q->ops->buf_release(q, q->bufs[i]);
}
INIT_LIST_HEAD(&q->stream);
}
/* --------------------------------------------------------------------- */
/* Locking: Caller holds q->lock */
enum v4l2_field videobuf_next_field(struct videobuf_queue *q)
{
enum v4l2_field field = q->field;
BUG_ON(V4L2_FIELD_ANY == field);
if (V4L2_FIELD_ALTERNATE == field) {
if (V4L2_FIELD_TOP == q->last) {
field = V4L2_FIELD_BOTTOM;
q->last = V4L2_FIELD_BOTTOM;
} else {
field = V4L2_FIELD_TOP;
q->last = V4L2_FIELD_TOP;
}
}
return field;
}
/* Locking: Caller holds q->lock */
static void videobuf_status(struct videobuf_queue *q, struct v4l2_buffer *b,
struct videobuf_buffer *vb, enum v4l2_buf_type type)
{
MAGIC_CHECK(vb->magic, MAGIC_BUFFER);
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
b->index = vb->i;
b->type = type;
b->memory = vb->memory;
switch (b->memory) {
case V4L2_MEMORY_MMAP:
b->m.offset = vb->boff;
b->length = vb->bsize;
break;
case V4L2_MEMORY_USERPTR:
b->m.userptr = vb->baddr;
b->length = vb->bsize;
break;
case V4L2_MEMORY_OVERLAY:
b->m.offset = vb->boff;
break;
}
b->flags = 0;
if (vb->map)
b->flags |= V4L2_BUF_FLAG_MAPPED;
switch (vb->state) {
case VIDEOBUF_PREPARED:
case VIDEOBUF_QUEUED:
case VIDEOBUF_ACTIVE:
b->flags |= V4L2_BUF_FLAG_QUEUED;
break;
case VIDEOBUF_DONE:
case VIDEOBUF_ERROR:
b->flags |= V4L2_BUF_FLAG_DONE;
break;
case VIDEOBUF_NEEDS_INIT:
case VIDEOBUF_IDLE:
/* nothing */
break;
}
if (vb->input != UNSET) {
b->flags |= V4L2_BUF_FLAG_INPUT;
b->input = vb->input;
}
b->field = vb->field;
b->timestamp = vb->ts;
b->bytesused = vb->size;
b->sequence = vb->field_count >> 1;
}
/* Locking: Caller holds q->lock */
static int __videobuf_mmap_free(struct videobuf_queue *q)
{
int i;
int rc;
if (!q)
return 0;
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
rc = CALL(q, mmap_free, q);
if (rc < 0)
return rc;
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
q->ops->buf_release(q, q->bufs[i]);
kfree(q->bufs[i]);
q->bufs[i] = NULL;
}
return rc;
}
int videobuf_mmap_free(struct videobuf_queue *q)
{
int ret;
mutex_lock(&q->lock);
ret = __videobuf_mmap_free(q);
mutex_unlock(&q->lock);
return ret;
}
/* Locking: Caller holds q->lock */
static int __videobuf_mmap_setup(struct videobuf_queue *q,
unsigned int bcount, unsigned int bsize,
enum v4l2_memory memory)
{
unsigned int i;
int err;
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
err = __videobuf_mmap_free(q);
if (0 != err)
return err;
/* Allocate and initialize buffers */
for (i = 0; i < bcount; i++) {
q->bufs[i] = videobuf_alloc(q);
if (q->bufs[i] == NULL)
break;
q->bufs[i]->i = i;
q->bufs[i]->input = UNSET;
q->bufs[i]->memory = memory;
q->bufs[i]->bsize = bsize;
switch (memory) {
case V4L2_MEMORY_MMAP:
q->bufs[i]->boff = bsize * i;
break;
case V4L2_MEMORY_USERPTR:
case V4L2_MEMORY_OVERLAY:
/* nothing */
break;
}
}
if (!i)
return -ENOMEM;
dprintk(1, "mmap setup: %d buffers, %d bytes each\n",
i, bsize);
return i;
}
int videobuf_mmap_setup(struct videobuf_queue *q,
unsigned int bcount, unsigned int bsize,
enum v4l2_memory memory)
{
int ret;
mutex_lock(&q->lock);
ret = __videobuf_mmap_setup(q, bcount, bsize, memory);
mutex_unlock(&q->lock);
return ret;
}
int videobuf_reqbufs(struct videobuf_queue *q,
struct v4l2_requestbuffers *req)
{
unsigned int size, count;
int retval;
if (req->count < 1) {
dprintk(1, "reqbufs: count invalid (%d)\n", req->count);
return -EINVAL;
}
if (req->memory != V4L2_MEMORY_MMAP &&
req->memory != V4L2_MEMORY_USERPTR &&
req->memory != V4L2_MEMORY_OVERLAY) {
dprintk(1, "reqbufs: memory type invalid\n");
return -EINVAL;
}
mutex_lock(&q->lock);
if (req->type != q->type) {
dprintk(1, "reqbufs: queue type invalid\n");
retval = -EINVAL;
goto done;
}
if (q->streaming) {
dprintk(1, "reqbufs: streaming already exists\n");
retval = -EBUSY;
goto done;
}
if (!list_empty(&q->stream)) {
dprintk(1, "reqbufs: stream running\n");
retval = -EBUSY;
goto done;
}
count = req->count;
if (count > VIDEO_MAX_FRAME)
count = VIDEO_MAX_FRAME;
size = 0;
q->ops->buf_setup(q, &count, &size);
size = PAGE_ALIGN(size);
dprintk(1, "reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
count, size, (count*size)>>PAGE_SHIFT);
retval = __videobuf_mmap_setup(q, count, size, req->memory);
if (retval < 0) {
dprintk(1, "reqbufs: mmap setup returned %d\n", retval);
goto done;
}
req->count = retval;
done:
mutex_unlock(&q->lock);
return retval;
}
int videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
{
int ret = -EINVAL;
mutex_lock(&q->lock);
if (unlikely(b->type != q->type)) {
dprintk(1, "querybuf: Wrong type.\n");
goto done;
}
if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME)) {
dprintk(1, "querybuf: index out of range.\n");
goto done;
}
if (unlikely(NULL == q->bufs[b->index])) {
dprintk(1, "querybuf: buffer is null.\n");
goto done;
}
videobuf_status(q, b, q->bufs[b->index], q->type);
ret = 0;
done:
mutex_unlock(&q->lock);
return ret;
}
int videobuf_qbuf(struct videobuf_queue *q,
struct v4l2_buffer *b)
{
struct videobuf_buffer *buf;
enum v4l2_field field;
unsigned long flags = 0;
int retval;
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
if (b->memory == V4L2_MEMORY_MMAP)
down_read(&current->mm->mmap_sem);
mutex_lock(&q->lock);
retval = -EBUSY;
if (q->reading) {
dprintk(1, "qbuf: Reading running...\n");
goto done;
}
retval = -EINVAL;
if (b->type != q->type) {
dprintk(1, "qbuf: Wrong type.\n");
goto done;
}
if (b->index < 0 || b->index >= VIDEO_MAX_FRAME) {
dprintk(1, "qbuf: index out of range.\n");
goto done;
}
buf = q->bufs[b->index];
if (NULL == buf) {
dprintk(1, "qbuf: buffer is null.\n");
goto done;
}
MAGIC_CHECK(buf->magic, MAGIC_BUFFER);
if (buf->memory != b->memory) {
dprintk(1, "qbuf: memory type is wrong.\n");
goto done;
}
if (buf->state != VIDEOBUF_NEEDS_INIT && buf->state != VIDEOBUF_IDLE) {
dprintk(1, "qbuf: buffer is already queued or active.\n");
goto done;
}
if (b->flags & V4L2_BUF_FLAG_INPUT) {
if (b->input >= q->inputs) {
dprintk(1, "qbuf: wrong input.\n");
goto done;
}
buf->input = b->input;
} else {
buf->input = UNSET;
}
switch (b->memory) {
case V4L2_MEMORY_MMAP:
if (0 == buf->baddr) {
dprintk(1, "qbuf: mmap requested "
"but buffer addr is zero!\n");
goto done;
}
break;
case V4L2_MEMORY_USERPTR:
if (b->length < buf->bsize) {
dprintk(1, "qbuf: buffer length is not enough\n");
goto done;
}
if (VIDEOBUF_NEEDS_INIT != buf->state &&
buf->baddr != b->m.userptr)
q->ops->buf_release(q, buf);
buf->baddr = b->m.userptr;
break;
case V4L2_MEMORY_OVERLAY:
buf->boff = b->m.offset;
break;
default:
dprintk(1, "qbuf: wrong memory type\n");
goto done;
}
dprintk(1, "qbuf: requesting next field\n");
field = videobuf_next_field(q);
retval = q->ops->buf_prepare(q, buf, field);
if (0 != retval) {
dprintk(1, "qbuf: buffer_prepare returned %d\n", retval);
goto done;
}
list_add_tail(&buf->stream, &q->stream);
if (q->streaming) {
if (q->irqlock)
spin_lock_irqsave(q->irqlock, flags);
q->ops->buf_queue(q, buf);
if (q->irqlock)
spin_unlock_irqrestore(q->irqlock, flags);
}
dprintk(1, "qbuf: succeded\n");
retval = 0;
done:
mutex_unlock(&q->lock);
if (b->memory == V4L2_MEMORY_MMAP)
up_read(&current->mm->mmap_sem);
return retval;
}
int videobuf_dqbuf(struct videobuf_queue *q,
struct v4l2_buffer *b, int nonblocking)
{
struct videobuf_buffer *buf;
int retval;
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
mutex_lock(&q->lock);
retval = -EBUSY;
if (q->reading) {
dprintk(1, "dqbuf: Reading running...\n");
goto done;
}
retval = -EINVAL;
if (b->type != q->type) {
dprintk(1, "dqbuf: Wrong type.\n");
goto done;
}
if (list_empty(&q->stream)) {
dprintk(1, "dqbuf: stream running\n");
goto done;
}
buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
retval = videobuf_waiton(buf, nonblocking, 1);
if (retval < 0) {
dprintk(1, "dqbuf: waiton returned %d\n", retval);
goto done;
}
switch (buf->state) {
case VIDEOBUF_ERROR:
dprintk(1, "dqbuf: state is error\n");
retval = -EIO;
CALL(q, sync, q, buf);
buf->state = VIDEOBUF_IDLE;
break;
case VIDEOBUF_DONE:
dprintk(1, "dqbuf: state is done\n");
CALL(q, sync, q, buf);
buf->state = VIDEOBUF_IDLE;
break;
default:
dprintk(1, "dqbuf: state invalid\n");
retval = -EINVAL;
goto done;
}
list_del(&buf->stream);
memset(b, 0, sizeof(*b));
videobuf_status(q, b, buf, q->type);
done:
mutex_unlock(&q->lock);
return retval;
}
int videobuf_streamon(struct videobuf_queue *q)
{
struct videobuf_buffer *buf;
unsigned long flags = 0;
int retval;
mutex_lock(&q->lock);
retval = -EBUSY;
if (q->reading)
goto done;
retval = 0;
if (q->streaming)
goto done;
q->streaming = 1;
if (q->irqlock)
spin_lock_irqsave(q->irqlock, flags);
list_for_each_entry(buf, &q->stream, stream)
if (buf->state == VIDEOBUF_PREPARED)
q->ops->buf_queue(q, buf);
if (q->irqlock)
spin_unlock_irqrestore(q->irqlock, flags);
done:
mutex_unlock(&q->lock);
return retval;
}
/* Locking: Caller holds q->lock */
static int __videobuf_streamoff(struct videobuf_queue *q)
{
if (!q->streaming)
return -EINVAL;
videobuf_queue_cancel(q);
q->streaming = 0;
return 0;
}
int videobuf_streamoff(struct videobuf_queue *q)
{
int retval;
mutex_lock(&q->lock);
retval = __videobuf_streamoff(q);
mutex_unlock(&q->lock);
return retval;
}
/* Locking: Caller holds q->lock */
static ssize_t videobuf_read_zerocopy(struct videobuf_queue *q,
char __user *data,
size_t count, loff_t *ppos)
{
enum v4l2_field field;
unsigned long flags = 0;
int retval;
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
/* setup stuff */
q->read_buf = videobuf_alloc(q);
if (NULL == q->read_buf)
return -ENOMEM;
q->read_buf->memory = V4L2_MEMORY_USERPTR;
q->read_buf->baddr = (unsigned long)data;
q->read_buf->bsize = count;
field = videobuf_next_field(q);
retval = q->ops->buf_prepare(q, q->read_buf, field);
if (0 != retval)
goto done;
/* start capture & wait */
if (q->irqlock)
spin_lock_irqsave(q->irqlock, flags);
q->ops->buf_queue(q, q->read_buf);
if (q->irqlock)
spin_unlock_irqrestore(q->irqlock, flags);
retval = videobuf_waiton(q->read_buf, 0, 0);
if (0 == retval) {
CALL(q, sync, q, q->read_buf);
if (VIDEOBUF_ERROR == q->read_buf->state)
retval = -EIO;
else
retval = q->read_buf->size;
}
done:
/* cleanup */
q->ops->buf_release(q, q->read_buf);
kfree(q->read_buf);
q->read_buf = NULL;
return retval;
}
ssize_t videobuf_read_one(struct videobuf_queue *q,
char __user *data, size_t count, loff_t *ppos,
int nonblocking)
{
enum v4l2_field field;
unsigned long flags = 0;
unsigned size, nbufs;
int retval;
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
mutex_lock(&q->lock);
nbufs = 1; size = 0;
q->ops->buf_setup(q, &nbufs, &size);
if (NULL == q->read_buf &&
count >= size &&
!nonblocking) {
retval = videobuf_read_zerocopy(q, data, count, ppos);
if (retval >= 0 || retval == -EIO)
/* ok, all done */
goto done;
/* fallback to kernel bounce buffer on failures */
}
if (NULL == q->read_buf) {
/* need to capture a new frame */
retval = -ENOMEM;
q->read_buf = videobuf_alloc(q);
dprintk(1, "video alloc=0x%p\n", q->read_buf);
if (NULL == q->read_buf)
goto done;
q->read_buf->memory = V4L2_MEMORY_USERPTR;
q->read_buf->bsize = count; /* preferred size */
field = videobuf_next_field(q);
retval = q->ops->buf_prepare(q, q->read_buf, field);
if (0 != retval) {
kfree(q->read_buf);
q->read_buf = NULL;
goto done;
}
if (q->irqlock)
spin_lock_irqsave(q->irqlock, flags);
q->ops->buf_queue(q, q->read_buf);
if (q->irqlock)
spin_unlock_irqrestore(q->irqlock, flags);
q->read_off = 0;
}
/* wait until capture is done */
retval = videobuf_waiton(q->read_buf, nonblocking, 1);
if (0 != retval)
goto done;
CALL(q, sync, q, q->read_buf);
if (VIDEOBUF_ERROR == q->read_buf->state) {
/* catch I/O errors */
q->ops->buf_release(q, q->read_buf);
kfree(q->read_buf);
q->read_buf = NULL;
retval = -EIO;
goto done;
}
/* Copy to userspace */
retval = CALL(q, video_copy_to_user, q, data, count, nonblocking);
if (retval < 0)
goto done;
q->read_off += retval;
if (q->read_off == q->read_buf->size) {
/* all data copied, cleanup */
q->ops->buf_release(q, q->read_buf);
kfree(q->read_buf);
q->read_buf = NULL;
}
done:
mutex_unlock(&q->lock);
return retval;
}
/* Locking: Caller holds q->lock */
int __videobuf_read_start(struct videobuf_queue *q)
{
enum v4l2_field field;
unsigned long flags = 0;
unsigned int count = 0, size = 0;
int err, i;
q->ops->buf_setup(q, &count, &size);
if (count < 2)
count = 2;
if (count > VIDEO_MAX_FRAME)
count = VIDEO_MAX_FRAME;
size = PAGE_ALIGN(size);
err = __videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
if (err < 0)
return err;
count = err;
for (i = 0; i < count; i++) {
field = videobuf_next_field(q);
err = q->ops->buf_prepare(q, q->bufs[i], field);
if (err)
return err;
list_add_tail(&q->bufs[i]->stream, &q->stream);
}
if (q->irqlock)
spin_lock_irqsave(q->irqlock, flags);
for (i = 0; i < count; i++)
q->ops->buf_queue(q, q->bufs[i]);
if (q->irqlock)
spin_unlock_irqrestore(q->irqlock, flags);
q->reading = 1;
return 0;
}
static void __videobuf_read_stop(struct videobuf_queue *q)
{
int i;
videobuf_queue_cancel(q);
__videobuf_mmap_free(q);
INIT_LIST_HEAD(&q->stream);
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
kfree(q->bufs[i]);
q->bufs[i] = NULL;
}
q->read_buf = NULL;
q->reading = 0;
}
int videobuf_read_start(struct videobuf_queue *q)
{
int rc;
mutex_lock(&q->lock);
rc = __videobuf_read_start(q);
mutex_unlock(&q->lock);
return rc;
}
void videobuf_read_stop(struct videobuf_queue *q)
{
mutex_lock(&q->lock);
__videobuf_read_stop(q);
mutex_unlock(&q->lock);
}
void videobuf_stop(struct videobuf_queue *q)
{
mutex_lock(&q->lock);
if (q->streaming)
__videobuf_streamoff(q);
if (q->reading)
__videobuf_read_stop(q);
mutex_unlock(&q->lock);
}
ssize_t videobuf_read_stream(struct videobuf_queue *q,
char __user *data, size_t count, loff_t *ppos,
int vbihack, int nonblocking)
{
int rc, retval;
unsigned long flags = 0;
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
dprintk(2, "%s\n", __FUNCTION__);
mutex_lock(&q->lock);
retval = -EBUSY;
if (q->streaming)
goto done;
if (!q->reading) {
retval = __videobuf_read_start(q);
if (retval < 0)
goto done;
}
retval = 0;
while (count > 0) {
/* get / wait for data */
if (NULL == q->read_buf) {
q->read_buf = list_entry(q->stream.next,
struct videobuf_buffer,
stream);
list_del(&q->read_buf->stream);
q->read_off = 0;
}
rc = videobuf_waiton(q->read_buf, nonblocking, 1);
if (rc < 0) {
if (0 == retval)
retval = rc;
break;
}
if (q->read_buf->state == VIDEOBUF_DONE) {
rc = CALL(q, copy_stream, q, data + retval, count,
retval, vbihack, nonblocking);
if (rc < 0) {
retval = rc;
break;
}
retval += rc;
count -= rc;
q->read_off += rc;
} else {
/* some error */
q->read_off = q->read_buf->size;
if (0 == retval)
retval = -EIO;
}
/* requeue buffer when done with copying */
if (q->read_off == q->read_buf->size) {
list_add_tail(&q->read_buf->stream,
&q->stream);
if (q->irqlock)
spin_lock_irqsave(q->irqlock, flags);
q->ops->buf_queue(q, q->read_buf);
if (q->irqlock)
spin_unlock_irqrestore(q->irqlock, flags);
q->read_buf = NULL;
}
if (retval < 0)
break;
}
done:
mutex_unlock(&q->lock);
return retval;
}
unsigned int videobuf_poll_stream(struct file *file,
struct videobuf_queue *q,
poll_table *wait)
{
struct videobuf_buffer *buf = NULL;
unsigned int rc = 0;
mutex_lock(&q->lock);
if (q->streaming) {
if (!list_empty(&q->stream))
buf = list_entry(q->stream.next,
struct videobuf_buffer, stream);
} else {
if (!q->reading)
__videobuf_read_start(q);
if (!q->reading) {
rc = POLLERR;
} else if (NULL == q->read_buf) {
q->read_buf = list_entry(q->stream.next,
struct videobuf_buffer,
stream);
list_del(&q->read_buf->stream);
q->read_off = 0;
}
buf = q->read_buf;
}
if (!buf)
rc = POLLERR;
if (0 == rc) {
poll_wait(file, &buf->done, wait);
if (buf->state == VIDEOBUF_DONE ||
buf->state == VIDEOBUF_ERROR)
rc = POLLIN|POLLRDNORM;
}
mutex_unlock(&q->lock);
return rc;
}
int videobuf_mmap_mapper(struct videobuf_queue *q,
struct vm_area_struct *vma)
{
int retval;
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
mutex_lock(&q->lock);
retval = CALL(q, mmap_mapper, q, vma);
mutex_unlock(&q->lock);
return retval;
}
#ifdef CONFIG_VIDEO_V4L1_COMPAT
int videobuf_cgmbuf(struct videobuf_queue *q,
struct video_mbuf *mbuf, int count)
{
struct v4l2_requestbuffers req;
int rc, i;
MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
memset(&req, 0, sizeof(req));
req.type = q->type;
req.count = count;
req.memory = V4L2_MEMORY_MMAP;
rc = videobuf_reqbufs(q, &req);
if (rc < 0)
return rc;
mbuf->frames = req.count;
mbuf->size = 0;
for (i = 0; i < mbuf->frames; i++) {
mbuf->offsets[i] = q->bufs[i]->boff;
mbuf->size += q->bufs[i]->bsize;
}
return 0;
}
EXPORT_SYMBOL_GPL(videobuf_cgmbuf);
#endif
/* --------------------------------------------------------------------- */
EXPORT_SYMBOL_GPL(videobuf_waiton);
EXPORT_SYMBOL_GPL(videobuf_iolock);
EXPORT_SYMBOL_GPL(videobuf_alloc);
EXPORT_SYMBOL_GPL(videobuf_queue_core_init);
EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
EXPORT_SYMBOL_GPL(videobuf_next_field);
EXPORT_SYMBOL_GPL(videobuf_reqbufs);
EXPORT_SYMBOL_GPL(videobuf_querybuf);
EXPORT_SYMBOL_GPL(videobuf_qbuf);
EXPORT_SYMBOL_GPL(videobuf_dqbuf);
EXPORT_SYMBOL_GPL(videobuf_streamon);
EXPORT_SYMBOL_GPL(videobuf_streamoff);
EXPORT_SYMBOL_GPL(videobuf_read_start);
EXPORT_SYMBOL_GPL(videobuf_read_stop);
EXPORT_SYMBOL_GPL(videobuf_stop);
EXPORT_SYMBOL_GPL(videobuf_read_stream);
EXPORT_SYMBOL_GPL(videobuf_read_one);
EXPORT_SYMBOL_GPL(videobuf_poll_stream);
EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
EXPORT_SYMBOL_GPL(videobuf_mmap_free);
EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);