From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pannaga Bhushan <bhushan@multitech.co.in>
Subject: pcm_lib.c . how does delta show wrong int. ack?
Date: Mon, 21 Oct 2002 09:21:16 +0530
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Hi all,
         In the file pcm_lib.c and in the funtion -
snd_pcm_hw_ptr_interrupt() ,  there are the following lines --

-----------------

delta = hw_ptr_interrupt - new_hw_ptr;
if(delta > 0) {
    if( delta < runtime->buffer_size / 2) {
        snd_printd("Unexpected hw_pointer value .... wrong interrupt
acknowledge?\n"...);
        return 0;
    }
    runtime->hw_ptr_base += runtime->buffer_size;
    -------
    ------
    -------
}

-----------------

Can you pls clarify what these lines are doing? what is the significance
of delta and the significance of delta > 0 but less than
runtime->buffer_size/2   being a case of wrong interrupt ack.

thanx in advance,
Pannaga Bhushan


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