From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932435Ab1HFAMQ (ORCPT ); Fri, 5 Aug 2011 20:12:16 -0400 Received: from cantor2.suse.de ([195.135.220.15]:39706 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964777Ab1HFAML (ORCPT ); Fri, 5 Aug 2011 20:12:11 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Fri Aug 5 17:04:11 2011 Message-Id: <20110806000411.628894019@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Fri, 05 Aug 2011 17:03:19 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Liam Girdwood , Mark Brown Subject: [01/50] ASoC: Fix Blackfin I2S _pointer() implementation return in bounds values In-Reply-To: <20110806000419.GA28392@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.33-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Mark Brown commit e999dc50404d401150a5429b6459473a691fd1a0 upstream. The Blackfin DMA controller can report one frame beyond the end of the buffer in the wraparound case but ALSA requires that the pointer always be in the buffer. Do the wraparound to handle this. A similar bug is likely to apply to the other Blackfin PCM drivers but the code is less obvious to inspection and I don't have a user to test. Reported-by: Kieran O'Leary Acked-by: Liam Girdwood Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- sound/soc/blackfin/bf5xx-i2s-pcm.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) --- a/sound/soc/blackfin/bf5xx-i2s-pcm.c +++ b/sound/soc/blackfin/bf5xx-i2s-pcm.c @@ -139,11 +139,20 @@ static snd_pcm_uframes_t bf5xx_pcm_point pr_debug("%s enter\n", __func__); if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { diff = sport_curr_offset_tx(sport); - frames = bytes_to_frames(substream->runtime, diff); } else { diff = sport_curr_offset_rx(sport); - frames = bytes_to_frames(substream->runtime, diff); } + + /* + * TX at least can report one frame beyond the end of the + * buffer if we hit the wraparound case - clamp to within the + * buffer as the ALSA APIs require. + */ + if (diff == snd_pcm_lib_buffer_bytes(substream)) + diff = 0; + + frames = bytes_to_frames(substream->runtime, diff); + return frames; }