From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: ALSA Control Questions (atomicity, error handling)
Date: Fri, 04 Dec 2009 13:33:17 +0100
Message-ID: <4B19018D.4040000@ladisch.de>
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To: Tobias Schneider <tobsnyder@gmx.de>
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Tobias Schneider wrote:
> Another point: I figured out that the "ALSA middlelayer" seems to filter
> the given values of a control. So if the user sets value=1000 where
> maximum is 10, I will get 10 instead of 1000 in the put callback...so
> it's not necessary to check values in those callbacks,

It is, because it is possible to use low-level ALSA functions or to call
the IOCTLs directly, and in this way arbitrary values can reach your
driver's put callback.


Best regards,
Clemens