From mboxrd@z Thu Jan  1 00:00:00 1970
From: pl bossart <bossart.nospam@gmail.com>
Subject: Re: [PATCH] ALSA: add support for disabling period irq
Date: Mon, 8 Nov 2010 15:43:15 -0600
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To: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>, alsa-devel@alsa-project.org
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done from the avail_update call invoked from an application.
>>
>> ok, so I re-implemented all the points found in the reviews except for
>> this thread. There's already some code to see if we go beyond the
>> buffer boundaries, so I am not sure what the 'linear position' means.
>
> Linear means that new hw_ptr must be always behind the previous hw_ptr.

I got that. But there are already some checks in pcm_lib.c,

	/* new_hw_ptr might be lower than old_hw_ptr in case when */
	/* pointer crosses the end of the ring buffer */
	if (new_hw_ptr < old_hw_ptr) {
		hw_base += runtime->buffer_size;
		if (hw_base >= runtime->boundary)
			hw_base = 0;
		new_hw_ptr = hw_base + pos;
	}

So do I need to add any additional checks? Or did I miss something in
your discussion with Takashi?
-Pierre