Re: [PATCH 3/3] ASoC: omap-mcbsp: Add period size protection mode

[Mark Brown <broonie@opensource.wolfsonmicro.com>]

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On Tue, Mar 20, 2012 at 07:27:02PM +0200, Grazvydas Ignotas wrote:
> On Tue, Mar 20, 2012 at 7:04 PM, Mark Brown
> > On Tue, Mar 20, 2012 at 06:15:34PM +0200, Grazvydas Ignotas wrote:

> >> I wouldn't really call them broken, it's enough to set period size to
> >> 512 with smaller start_threshold (something like 50ms) to have
> >> problems, those parameters are perfectly valid for a program trying to
> >> achieve low latency.

> > If they can't cope with the parameters they've set I'd call them broken,
> > they should've asked for more sensible parameters.

> How is the program supposed to know those parameters are invalid for
> this hardware? It could maybe detect underflows and increase period
> until underflows stop, but there might be other reasons for underflows
> like high system load. Or do you mean setting up some period size and
> doing writes of that period size is not valid thing to do? Currently,
> no matter how fast the writes come, there is an underflow after first
> write in these conditions.

In that case why is the fix specific to this application and not a
generic one?  If we're going to underflow no matter what then why make
the workaround custom?

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