UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

V4L/DVB (8088): ivtv: yuv decoder lock fix 

write() operations to the yuv device may not always 'start' the decoder.
Although yuv output will be correct, some functions which should be disabled
while the decoder is in use remain enabled. This can result in hardware
registers being corrupted, causing problems with the mpeg decoder. This patch
simply moves the existing decoder 'start' sequence to earlier in the write()
handler.

Signed-off-by: Ian Armstrong <ian@iarmst.demon.co.uk>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Ian Armstrong 2008-06-21 09:25:23 -03:00 committed by Mauro Carvalho Chehab
parent 0b5a30e90d
commit 464e9f3a0c
1 changed files with 13 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
drivers/media/video/ivtv/ivtv-fileops.c
View File

@ -582,6 +582,19 @@ ssize_t ivtv_v4l2_write(struct file *filp, const char __user *user_buf, size_t c
ivtv_queue_init(&q);
set_bit(IVTV_F_S_APPL_IO, &s->s_flags);
/* Start decoder (returns 0 if already started) */
mutex_lock(&itv->serialize_lock);
rc = ivtv_start_decoding(id, itv->speed);
mutex_unlock(&itv->serialize_lock);
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 */
@ -664,18 +677,6 @@ retry:
ivtv_enqueue(s, buf, &s->q_full);
}
/* Start decoder (returns 0 if already started) */
mutex_lock(&itv->serialize_lock);
rc = ivtv_start_decoding(id, itv->speed);
mutex_unlock(&itv->serialize_lock);
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;
}
if (test_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags)) {
if (s->q_full.length >= itv->dma_data_req_size) {
int got_sig;