From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933476Ab3B0Az5 (ORCPT ); Tue, 26 Feb 2013 19:55:57 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:42098 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932146Ab3BZX6H (ORCPT ); Tue, 26 Feb 2013 18:58:07 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ryo Tsutsui , Charles Keepax , Mark Brown Subject: [ 100/150] ASoC: arizona: Fixed a bug in FLL fractional calculation Date: Tue, 26 Feb 2013 15:55:57 -0800 Message-Id: <20130226235534.430497486@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130226235523.930663721@linuxfoundation.org> References: <20130226235523.930663721@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ryo Tsutsui commit 01f58153aefc158fd690b337d29ad140e963959d upstream. Previously arizona_calc_fll() was checking if the target frequency is exactly divisible by reference frequency, but should have been product of the ratio and the reference frequency. Also scale down the Lamba and Theta coefficients be under 16-bits in order to match the registers. Signed-off-by: Ryo Tsutsui Signed-off-by: Charles Keepax Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- sound/soc/codecs/arizona.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) --- a/sound/soc/codecs/arizona.c +++ b/sound/soc/codecs/arizona.c @@ -910,7 +910,7 @@ static int arizona_calc_fll(struct arizo cfg->n = target / (ratio * Fref); - if (target % Fref) { + if (target % (ratio * Fref)) { gcd_fll = gcd(target, ratio * Fref); arizona_fll_dbg(fll, "GCD=%u\n", gcd_fll); @@ -922,6 +922,15 @@ static int arizona_calc_fll(struct arizo cfg->lambda = 0; } + /* Round down to 16bit range with cost of accuracy lost. + * Denominator must be bigger than numerator so we only + * take care of it. + */ + while (cfg->lambda >= (1 << 16)) { + cfg->theta >>= 1; + cfg->lambda >>= 1; + } + arizona_fll_dbg(fll, "N=%x THETA=%x LAMBDA=%x\n", cfg->n, cfg->theta, cfg->lambda); arizona_fll_dbg(fll, "FRATIO=%x(%d) OUTDIV=%x REFCLK_DIV=%x\n",