[PATCH] ALSA: pcm: fix incorrect hw_base increase

[Lu, Brent]

> 
> Is this a bugfix needed for older kernels as well?  When did this issue show
> up?
> 
> thanks,
> 
> greg k-h

It happens when DMA stop moving data from host to DSP/DAI for a long time
(> half of buffer time). I know host driver should do something about it. But if
not, the HWSYNC will keep increasing the hw_base and hw_ptr and confuses
user space program.

Regards,
Brent