74 2014-11-16 下午8:31 於 "Peter Meerwald" <<a href="mailto:pmeerw@pmeerw.net">pmeerw@pmeerw.net</a>> 寫道： > > > > > as suggested by > > ><a href="https://bugs.freedesktop.org/show_bug.cgi?id=84804">https://bugs.freedesktop.org/show_bug.cgi?id=84804</a> > > > > > > Signed-off-by: Peter Meerwald <<a href="mailto:pmeerw@pmeerw.net">pmeerw@pmeerw.net</a>> > > > --- > > > src/modules/alsa/alsa-util.c | 15 +++++++++++++++ > > > 1 file changed, 15 insertions(+) > > > > > > diff --git a/src/modules/alsa/alsa-util.c b/src/modules/alsa/alsa-util.c > > > index 4131cff..e382d4f 100644 > > > --- a/src/modules/alsa/alsa-util.c > > > +++ b/src/modules/alsa/alsa-util.c > > > @@ -183,6 +183,19 @@ static int set_buffer_size(snd_pcm_t *pcm_handle, > > snd_pcm_hw_params_t *hwparams, > > > return 0; > > > } > > > > > > +static void check_access(snd_pcm_t *pcm_handle, snd_pcm_hw_params_t > > *hwparams, bool use_mmap) { > > > + if ((use_mmap && !snd_pcm_hw_params_test_access(pcm_handle, > > hwparams, SND_PCM_ACCESS_MMAP_INTERLEAVED)) || > > > + !snd_pcm_hw_params_test_access(pcm_handle, hwparams, > > SND_PCM_ACCESS_RW_INTERLEAVED)) > > > + pa_log_error("Weird, PCM claims to support interleaved access, > > but snd_pcm_hw_params_set_access() failed."); > > > > HW Params of device "hw:0,0": > > -------------------- > > ACCESS: MMAP_NONINTERLEAVED RW_NONINTERLEAVED > > FORMAT: S32_LE > > SUBFORMAT: STD > > SAMPLE_BITS: 32 > > FRAME_BITS: [448 832] > > CHANNELS: [14 26] > > RATE: [32000 96000] > > PERIOD_TIME: (666 256000] > > PERIOD_SIZE: [64 8192] > > PERIOD_BYTES: [3584 851968] > > PERIODS: 2 > > BUFFER_TIME: (1333 512000] > > BUFFER_SIZE: [128 16384] > > BUFFER_BYTES: [7168 1703936] > > TICK_TIME: ALL > > > > if use of test_access is to prevent set_access corrupt the configuration > > space of hw_param when access is not supported, > > I am not sure if I understand your comment correctly > > the idea of the patch is to improve the logging in case _INTERLEAVED is > not supported (but NONINTERLEAVED is) > > I don't want to change the current behaviour in the normal case, hence > check_access() is called after trying to set the access method > > what do you means with corruption of config space? > If the application did not explicilty set_access snd_pcm_hw_params() choose the first supported access from the configuration space created by snd_pcm_hw_params_any() this mean that if pulseaudio use test_access to find the access is supported and set_access for those two non interleaved access types( i.e. not set_access for any unsupported access type) the configuration space is left with mmap non interleaved, non interleaved or complex which are not supported by pulseaudio snd_pcm_hw_params() will select first supported access from configuration space mmap non interleaved for rme9652 for example, snd_output_stdio_attach(&log, stderr, 0); snd_pcm_hw_params_any(pars); snd_pcm_hw_params_dump(pars, log); snd_pcm_hw_params(pcm,pars); snd_pcm_dump(pcm, log) the first supported access for snd-hda-intel which is mmap interleaved will be selected when the application did not explicitly set the access type