[alsa-devel] [PATCH 1/3] add API to allow disabling period interrupts

pl bossart bossart.nospam at gmail.com
Mon May 17 18:05:15 CEST 2010

> 2) The avail_min parameter in sw_params was overlooked. The lowlevel
>   drivers can use this value to compute the wake-up point and set hw
>   appropriately, to do wake-up at requested time. We can add a support
>   functions like "return how many samples are expected to be transferred
>   for next wake-up point" to linux/sound/pcm.h. In case when this value
>   is high, no interrupts (wake ups) will be processed in the driver. If
>   hardware cannot do the precise transfers, we can program a system
>   timer as the wake-up source.

Isn't the interrupt-related behavior defined when you setup the DMA
linked list. i.e when hw_params are frozen? The problem with sw_params
is that they can change at any time, and the hardware may not support
this. I have no idea how you would modify the HDAudio controller
behavior dynamically for example.

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