Backends don't necessarily allow for opening the same device multiple
times, and it shouldn't be necessary.
Since source and sink are not necessarily both running at the same time,
refcount the transport acquire/release so that it knows to close the fd
only when no source/sink is running.
Let the transport manage the fd lifecycle, also closing it once it is
not needed.
Don't return the fd from acquire(), since each transport is associated
with a single socket fd.
Wrap read() with the CHECK() used elsewhre in the test program, in order
to render out the compiler warning represented by this transcript:
➜ pipewire (af38edea) ✔ make
ninja -C /home/jarkko/Projects/pipewire/build
ninja: Entering directory `/home/jarkko/Projects/pipewire/build'
[6/397] Compiling C object spa/plugins/alsa/test-timer.p/test-timer.c.o
../spa/plugins/alsa/test-timer.c: In function ‘main’:
../spa/plugins/alsa/test-timer.c:195:3: warning: ignoring return value of ‘read’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
195 | read(state.timerfd, &expirations, sizeof(expirations));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@iki.fi>
Use a different way to generate the upper bits of the ASYNC mask
instead of undefined shift as warned by sanitizer
Add some unit test for this
See #497
Instead of using a hardcoded value for the minimum delay between writes,
select it according to the mtu/packet size that is currently used.
This is necessary for correct playback with lower mtu values.
Kernel should provide the correct mtu/packet size to use for SCO socket
I/O, but it does not currently appear to (as of linux 5.9), see
https://lore.kernel.org/linux-bluetooth/20201210003528.3pmaxvubiwegxmhl@pali/T/
When using mSBC, instead of using the (incorrect) kernel-provided value,
hardcode mtu to 24, corresponding to ALT1 mode. BT-UART adapters should
not require specific mtu, and it appears most BT-USB adapters only
support ALT1, see
https://lore.kernel.org/linux-bluetooth/20201210012003.133000-1-tpiepho@gmail.com/
This code needs to be revised when the issue is sorted out on the kernel
side.
Add setting bluez5.msbc-force-mtu for easier debugging in special cases.
Leave read_mtu as the detected value --- it does not seem to affect
whether BT-USB can record, but Raspberry Pi BT-UART fails to record if a
different value is used.
Currently alsa_read and alsa_write assumes that all the frames committed
using snd_pcm_mmap_commit are read or written, which is probably true.
However, as it could be some corner cases add a warning to notice this
fact.
Signed-off-by: Walter Lozano <walter.lozano@collabora.com>
