Re: safe support for rewind in ALSA

[Raymond Yau <superquad.vortex2@gmail.com>]

2010/2/10 Kai Vehmanen <kvehmanen@eca.cx>

> Hi,
>
>
> On Tue, 9 Feb 2010, Raymond Yau wrote:
>
>
>  why do PA insist to use one period per buffer when only those ISA drivers
>> and intel8x0 have periods_min =1 , the most common HDA driver and most
>> sound
>> cards have periods_min =2 ?
>>
>
> That is discussed at length here:
> http://0pointer.de/blog/projects/pulse-glitch-free.html
>


most of the motherboard which have ISA bus for the ISA sound card did not
have high resolution timer ( PA glitch free mode require high resolution
timer )

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 ?

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
?