diff options
| author | Roland Stoll <roland@xindex.de> | 2008-02-11 19:00:34 +0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@infradead.org> | 2008-02-18 17:15:19 +0300 |
| commit | 27d0fe189437803d5ad146d508ec2fd77252c73f (patch) | |
| tree | 848a078d589dfe3abc969a4fd75859812242d0b6 /drivers/media/video/cx88/cx88-mpeg.c | |
| parent | 968fb08912880e34a05a0cca7907392bac920aa2 (diff) | |
| download | linux-27d0fe189437803d5ad146d508ec2fd77252c73f.tar.xz | |
V4L/DVB (7194): cx88-mpeg: Allow concurrent access to cx88-mpeg devices
It currently isn't possible to open the frontend device of cx88-mpeg devices
(DVB or Blackbird) multiple times concurrently. (for instance, to attach a
signal monitoring tool while reading a stream, or to send a frequency change
ioctl) This patch fixes that condition.
Signed-off-by: Roland Stoll <roland@xindex.de>
Signed-off-by: Ricardo Cerqueira <v4l@cerqueira.org>
Reviewed-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Diffstat (limited to 'drivers/media/video/cx88/cx88-mpeg.c')
| -rw-r--r-- | drivers/media/video/cx88/cx88-mpeg.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/drivers/media/video/cx88/cx88-mpeg.c b/drivers/media/video/cx88/cx88-mpeg.c index 0aedbeaf94cd..f12733d6bf72 100644 --- a/drivers/media/video/cx88/cx88-mpeg.c +++ b/drivers/media/video/cx88/cx88-mpeg.c @@ -609,13 +609,19 @@ static int cx8802_request_acquire(struct cx8802_driver *drv) struct cx88_core *core = drv->core; /* Fail a request for hardware if the device is busy. */ - if (core->active_type_id != CX88_BOARD_NONE) + if (core->active_type_id != CX88_BOARD_NONE && + core->active_type_id != drv->type_id) return -EBUSY; if (drv->advise_acquire) { - core->active_type_id = drv->type_id; - drv->advise_acquire(drv); + core->active_ref++; + mutex_lock(&drv->core->lock); + if (core->active_type_id == CX88_BOARD_NONE) { + core->active_type_id = drv->type_id; + drv->advise_acquire(drv); + } + mutex_unlock(&drv->core->lock); mpeg_dbg(1,"%s() Post acquire GPIO=%x\n", __FUNCTION__, cx_read(MO_GP0_IO)); } @@ -628,10 +634,12 @@ static int cx8802_request_release(struct cx8802_driver *drv) { struct cx88_core *core = drv->core; - if (drv->advise_release) + if (drv->advise_release && --core->active_ref == 0) { + mutex_lock(&drv->core->lock); drv->advise_release(drv); core->active_type_id = CX88_BOARD_NONE; + mutex_unlock(&drv->core->lock); mpeg_dbg(1,"%s() Post release GPIO=%x\n", __FUNCTION__, cx_read(MO_GP0_IO)); } |