2010/2/10 Clemens Ladisch clemens@ladisch.de
Raymond Yau wrote:
... The rest of those sound cards which have period_mins = 1 are regarded as broken by PA developer (e.g. intel8x0 ,emu10k1 , ens1371 , ... ) and
aplay
did not work with one period per buffer too.
what is the hardware requirement for the driver to support one period per buffer ?
That the hardware can be programmed to generate only one interrupt per buffer.
if none of the those driver can be fixed why don't we change the period_min of all those broken drivers from 1 to
2
?
Because period_min has nothing to do with the brokenness. PA wants to use as few periods as possible because it does not use period interrupts but the DMA pointer, and it's the latter that is broken.
Regards, Clemens
Are the one period per buffer designed for specific purpose such as playing/looping the pre-loaded soundfont ?
Other than pulseaudio , are there any application use this mode properly without glitch ?
Do you mean that PA only wake up once when configure sound card to use two periods per buffer ?
if sound card only support non-interleaved mode and exactly two periods , even if you limit the rewind of application pointer to the period boundary is not 100% safe if the sound card pre-fetch audio using DMA
Most sound cards hardware register only provide the number of sample processed