From mboxrd@z Thu Jan  1 00:00:00 1970
From: Timur Tabi <timur@tabi.org>
Subject: Re: [PATCH v2] ASoC: fsl_ssi: Fix channel swap on
	playback start
Date: Mon, 3 Apr 2017 19:07:42 -0500
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To: Nicolin Chen <nicoleotsuka@gmail.com>, Caleb Crome <caleb@crome.org>
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Nicolin Chen wrote:
> So your test case involve both TX and RX. That's why this change
> would impact it. My understanding is: because you can not enable
> TX and RX in the same time from user space but only through two
> separate back-to-back system calls. So when the 2nd system call
> happens (RX for example), the RE bit, supposed to be enabled by
> this 2nd system call, has already been set by the 1st TX system
> call -- there's some random data in the RX FIFO already.

This makes sense to me.  I don't have the bandwidth to test it just yet, but I 
suspect that this patch will break PowerPC systems as well.