static void ivtv_stream_init(struct ivtv *itv, int type)
{
struct ivtv_stream *s = &itv->streams[type];
struct video_device *vdev = s->vdev;
/* we need to keep vdev, so restore it afterwards */
memset(s, 0, sizeof(*s));
s->vdev = vdev;
/* initialize ivtv_stream fields */
s->itv = itv;
s->type = type;
s->name = ivtv_stream_info[type].name;
s->caps = ivtv_stream_info[type].v4l2_caps;
if (ivtv_stream_info[type].pio)
s->dma = PCI_DMA_NONE;
else
s->dma = ivtv_stream_info[type].dma;
s->buf_size = itv->stream_buf_size[type];
if (s->buf_size)
s->buffers = (itv->options.kilobytes[type] * 1024 + s->buf_size - 1) / s->buf_size;
spin_lock_init(&s->qlock);
init_waitqueue_head(&s->waitq);
s->sg_handle = IVTV_DMA_UNMAPPED;
ivtv_queue_init(&s->q_free);
ivtv_queue_init(&s->q_full);
ivtv_queue_init(&s->q_dma);
ivtv_queue_init(&s->q_predma);
ivtv_queue_init(&s->q_io);
}
static ssize_t ivtv_write(struct file *filp, const char __user *user_buf, size_t count, loff_t *pos)
{
struct ivtv_open_id *id = fh2id(filp->private_data);
struct ivtv *itv = id->itv;
struct ivtv_stream *s = &itv->streams[id->type];
struct yuv_playback_info *yi = &itv->yuv_info;
struct ivtv_buffer *buf;
struct ivtv_queue q;
int bytes_written = 0;
int mode;
int rc;
DEFINE_WAIT(wait);
IVTV_DEBUG_HI_FILE("write %zd bytes to %s\n", count, s->name);
if (s->type != IVTV_DEC_STREAM_TYPE_MPG &&
s->type != IVTV_DEC_STREAM_TYPE_YUV &&
s->type != IVTV_DEC_STREAM_TYPE_VOUT)
/* not decoder streams */
return -EINVAL;
/* Try to claim this stream */
if (ivtv_claim_stream(id, s->type))
return -EBUSY;
/* This stream does not need to start any decoding */
if (s->type == IVTV_DEC_STREAM_TYPE_VOUT) {
int elems = count / sizeof(struct v4l2_sliced_vbi_data);
set_bit(IVTV_F_S_APPL_IO, &s->s_flags);
return ivtv_write_vbi_from_user(itv,
(const struct v4l2_sliced_vbi_data __user *)user_buf, elems);
}
mode = s->type == IVTV_DEC_STREAM_TYPE_MPG ? OUT_MPG : OUT_YUV;
if (ivtv_set_output_mode(itv, mode) != mode) {
ivtv_release_stream(s);
return -EBUSY;
}
ivtv_queue_init(&q);
set_bit(IVTV_F_S_APPL_IO, &s->s_flags);
/* Start decoder (returns 0 if already started) */
rc = ivtv_start_decoding(id, itv->speed);
if (rc) {
IVTV_DEBUG_WARN("Failed start decode stream %s\n", s->name);
/* failure, clean up */
clear_bit(IVTV_F_S_STREAMING, &s->s_flags);
clear_bit(IVTV_F_S_APPL_IO, &s->s_flags);
return rc;
}
retry:
/* If possible, just DMA the entire frame - Check the data transfer size
since we may get here before the stream has been fully set-up */
if (mode == OUT_YUV && s->q_full.length == 0 && itv->dma_data_req_size) {
while (count >= itv->dma_data_req_size) {
rc = ivtv_yuv_udma_stream_frame(itv, (void __user *)user_buf);
if (rc < 0)
return rc;
bytes_written += itv->dma_data_req_size;
user_buf += itv->dma_data_req_size;
count -= itv->dma_data_req_size;
}
if (count == 0) {
IVTV_DEBUG_HI_FILE("Wrote %d bytes to %s (%d)\n", bytes_written, s->name, s->q_full.bytesused);
return bytes_written;
}
}
for (;;) {
/* Gather buffers */
while (q.length - q.bytesused < count && (buf = ivtv_dequeue(s, &s->q_io)))
ivtv_enqueue(s, buf, &q);
while (q.length - q.bytesused < count && (buf = ivtv_dequeue(s, &s->q_free))) {
ivtv_enqueue(s, buf, &q);
}
if (q.buffers)
break;
if (filp->f_flags & O_NONBLOCK)
return -EAGAIN;
mutex_unlock(&itv->serialize_lock);
prepare_to_wait(&s->waitq, &wait, TASK_INTERRUPTIBLE);
/* New buffers might have become free before we were added to the waitqueue */
if (!s->q_free.buffers)
schedule();
finish_wait(&s->waitq, &wait);
mutex_lock(&itv->serialize_lock);
if (signal_pending(current)) {
IVTV_DEBUG_INFO("User stopped %s\n", s->name);
return -EINTR;
}
}
/* copy user data into buffers */
while ((buf = ivtv_dequeue(s, &q))) {
/* yuv is a pain. Don't copy more data than needed for a single
frame, otherwise we lose sync with the incoming stream */
if (s->type == IVTV_DEC_STREAM_TYPE_YUV &&
yi->stream_size + count > itv->dma_data_req_size)
rc = ivtv_buf_copy_from_user(s, buf, user_buf,
itv->dma_data_req_size - yi->stream_size);
else
rc = ivtv_buf_copy_from_user(s, buf, user_buf, count);
/* Make sure we really got all the user data */
if (rc < 0) {
ivtv_queue_move(s, &q, NULL, &s->q_free, 0);
return rc;
}
user_buf += rc;
count -= rc;
bytes_written += rc;
if (s->type == IVTV_DEC_STREAM_TYPE_YUV) {
yi->stream_size += rc;
/* If we have a complete yuv frame, break loop now */
if (yi->stream_size == itv->dma_data_req_size) {
ivtv_enqueue(s, buf, &s->q_full);
yi->stream_size = 0;
break;
}
}
if (buf->bytesused != s->buf_size) {
/* incomplete, leave in q_io for next time */
ivtv_enqueue(s, buf, &s->q_io);
break;
}
/* Byteswap MPEG buffer */
if (s->type == IVTV_DEC_STREAM_TYPE_MPG)
ivtv_buf_swap(buf);
ivtv_enqueue(s, buf, &s->q_full);
}
if (test_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags)) {
if (s->q_full.length >= itv->dma_data_req_size) {
int got_sig;
if (mode == OUT_YUV)
ivtv_yuv_setup_stream_frame(itv);
mutex_unlock(&itv->serialize_lock);
prepare_to_wait(&itv->dma_waitq, &wait, TASK_INTERRUPTIBLE);
while (!(got_sig = signal_pending(current)) &&
test_bit(IVTV_F_S_DMA_PENDING, &s->s_flags)) {
schedule();
}
finish_wait(&itv->dma_waitq, &wait);
mutex_lock(&itv->serialize_lock);
if (got_sig) {
IVTV_DEBUG_INFO("User interrupted %s\n", s->name);
return -EINTR;
}
clear_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags);
ivtv_queue_move(s, &s->q_full, NULL, &s->q_predma, itv->dma_data_req_size);
ivtv_dma_stream_dec_prepare(s, itv->dma_data_req_offset + IVTV_DECODER_OFFSET, 1);
}
}
/* more user data is available, wait until buffers become free
to transfer the rest. */
if (count && !(filp->f_flags & O_NONBLOCK))
goto retry;
IVTV_DEBUG_HI_FILE("Wrote %d bytes to %s (%d)\n", bytes_written, s->name, s->q_full.bytesused);
return bytes_written;
}