static ssize_t cx18_read(struct cx18_stream *s, char __user *ubuf,
size_t tot_count, int non_block)
{
struct cx18 *cx = s->cx;
size_t tot_written = 0;
int single_frame = 0;
if (atomic_read(&cx->ana_capturing) == 0 && s->id == -1) {
/* shouldn't happen */
CX18_DEBUG_WARN("Stream %s not initialized before read\n",
s->name);
return -EIO;
}
/* Each VBI buffer is one frame, the v4l2 API says that for VBI the
frames should arrive one-by-one, so make sure we never output more
than one VBI frame at a time */
if (s->type == CX18_ENC_STREAM_TYPE_VBI && !cx18_raw_vbi(cx))
single_frame = 1;
for (;;) {
struct cx18_buffer *buf;
int rc;
buf = cx18_get_buffer(s, non_block, &rc);
/* if there is no data available... */
if (buf == NULL) {
/* if we got data, then return that regardless */
if (tot_written)
break;
/* EOS condition */
if (rc == 0) {
clear_bit(CX18_F_S_STREAMOFF, &s->s_flags);
clear_bit(CX18_F_S_APPL_IO, &s->s_flags);
cx18_release_stream(s);
}
/* set errno */
return rc;
}
rc = cx18_copy_buf_to_user(s, buf, ubuf + tot_written,
tot_count - tot_written);
if (buf != &cx->vbi.sliced_mpeg_buf) {
if (buf->readpos == buf->bytesused)
cx18_stream_put_buf_fw(s, buf);
else
cx18_push(s, buf, &s->q_full);
} else if (buf->readpos == buf->bytesused) {
int idx = cx->vbi.inserted_frame % CX18_VBI_FRAMES;
cx->vbi.sliced_mpeg_size[idx] = 0;
cx->vbi.inserted_frame++;
cx->vbi_data_inserted += buf->bytesused;
}
if (rc < 0)
return rc;
tot_written += rc;
if (tot_written == tot_count || single_frame)
break;
}
return tot_written;
}
static void epu_dma_done(struct cx18 *cx, struct cx18_epu_work_order *order)
{
u32 handle, mdl_ack_count, id;
struct cx18_mailbox *mb;
struct cx18_mdl_ack *mdl_ack;
struct cx18_stream *s;
struct cx18_buffer *buf;
int i;
mb = &order->mb;
handle = mb->args[0];
s = cx18_handle_to_stream(cx, handle);
if (s == NULL) {
CX18_WARN("Got DMA done notification for unknown/inactive"
" handle %d, %s mailbox seq no %d\n", handle,
(order->flags & CX18_F_EWO_MB_STALE_UPON_RECEIPT) ?
"stale" : "good", mb->request);
return;
}
mdl_ack_count = mb->args[2];
mdl_ack = order->mdl_ack;
for (i = 0; i < mdl_ack_count; i++, mdl_ack++) {
id = mdl_ack->id;
/*
* Simple integrity check for processing a stale (and possibly
* inconsistent mailbox): make sure the buffer id is in the
* valid range for the stream.
*
* We go through the trouble of dealing with stale mailboxes
* because most of the time, the mailbox data is still valid and
* unchanged (and in practice the firmware ping-pongs the
* two mdl_ack buffers so mdl_acks are not stale).
*
* There are occasions when we get a half changed mailbox,
* which this check catches for a handle & id mismatch. If the
* handle and id do correspond, the worst case is that we
* completely lost the old buffer, but pick up the new buffer
* early (but the new mdl_ack is guaranteed to be good in this
* case as the firmware wouldn't point us to a new mdl_ack until
* it's filled in).
*
* cx18_queue_get buf() will detect the lost buffers
* and send them back to q_free for fw rotation eventually.
*/
if ((order->flags & CX18_F_EWO_MB_STALE_UPON_RECEIPT) &&
!(id >= s->mdl_offset &&
id < (s->mdl_offset + s->buffers))) {
CX18_WARN("Fell behind! Ignoring stale mailbox with "
" inconsistent data. Lost buffer for mailbox "
"seq no %d\n", mb->request);
break;
}
buf = cx18_queue_get_buf(s, id, mdl_ack->data_used);
CX18_DEBUG_HI_DMA("DMA DONE for %s (buffer %d)\n", s->name, id);
if (buf == NULL) {
CX18_WARN("Could not find buf %d for stream %s\n",
id, s->name);
/* Put as many buffers as possible back into fw use */
cx18_stream_load_fw_queue(s);
continue;
}
if (s->type == CX18_ENC_STREAM_TYPE_TS && s->dvb.enabled) {
CX18_DEBUG_HI_DMA("TS recv bytesused = %d\n",
buf->bytesused);
dvb_dmx_swfilter(&s->dvb.demux, buf->buf,
buf->bytesused);
}
/* Put as many buffers as possible back into fw use */
cx18_stream_load_fw_queue(s);
/* Put back TS buffer, since it was removed from all queues */
if (s->type == CX18_ENC_STREAM_TYPE_TS)
cx18_stream_put_buf_fw(s, buf);
}
wake_up(&cx->dma_waitq);
if (s->id != -1)
wake_up(&s->waitq);
}
static struct cx18_buffer *cx18_get_buffer(struct cx18_stream *s, int non_block, int *err)
{
struct cx18 *cx = s->cx;
struct cx18_stream *s_vbi = &cx->streams[CX18_ENC_STREAM_TYPE_VBI];
struct cx18_buffer *buf;
DEFINE_WAIT(wait);
*err = 0;
while (1) {
if (s->type == CX18_ENC_STREAM_TYPE_MPG) {
if (time_after(jiffies, cx->dualwatch_jiffies + msecs_to_jiffies(1000))) {
cx->dualwatch_jiffies = jiffies;
cx18_dualwatch(cx);
}
if (test_bit(CX18_F_S_INTERNAL_USE, &s_vbi->s_flags) &&
!test_bit(CX18_F_S_APPL_IO, &s_vbi->s_flags)) {
while ((buf = cx18_dequeue(s_vbi, &s_vbi->q_full))) {
/* byteswap and process VBI data */
cx18_process_vbi_data(cx, buf,
s_vbi->dma_pts,
s_vbi->type);
cx18_stream_put_buf_fw(s_vbi, buf);
}
}
buf = &cx->vbi.sliced_mpeg_buf;
if (buf->readpos != buf->bytesused)
return buf;
}
/* do we have new data? */
buf = cx18_dequeue(s, &s->q_full);
if (buf) {
if (!test_and_clear_bit(CX18_F_B_NEED_BUF_SWAP,
&buf->b_flags))
return buf;
if (s->type == CX18_ENC_STREAM_TYPE_MPG)
/* byteswap MPG data */
cx18_buf_swap(buf);
else {
/* byteswap and process VBI data */
cx18_process_vbi_data(cx, buf,
s->dma_pts, s->type);
}
return buf;
}
/* return if end of stream */
if (!test_bit(CX18_F_S_STREAMING, &s->s_flags)) {
CX18_DEBUG_INFO("EOS %s\n", s->name);
return NULL;
}
/* return if file was opened with O_NONBLOCK */
if (non_block) {
*err = -EAGAIN;
return NULL;
}
/* wait for more data to arrive */
prepare_to_wait(&s->waitq, &wait, TASK_INTERRUPTIBLE);
/* New buffers might have become available before we were added
to the waitqueue */
if (!atomic_read(&s->q_full.buffers))
schedule();
finish_wait(&s->waitq, &wait);
if (signal_pending(current)) {
/* return if a signal was received */
CX18_DEBUG_INFO("User stopped %s\n", s->name);
*err = -EINTR;
return NULL;
}
}
}
