From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755279AbdARLTy (ORCPT ); Wed, 18 Jan 2017 06:19:54 -0500 Received: from mga06.intel.com ([134.134.136.31]:37832 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753262AbdARLTw (ORCPT ); Wed, 18 Jan 2017 06:19:52 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,249,1477983600"; d="scan'208";a="810311971" Date: Wed, 18 Jan 2017 13:09:48 +0200 From: Mika Westerberg To: Thierry Reding Cc: Clemens Gruber , linux-pwm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-stable@vger.kernel.org, Florian Vaussard , Andy Shevchenko Subject: Re: [PATCH 1/2] pwm: pca9685: fix period change with same duty cycle Message-ID: <20170118110948.GN2023@lahna.fi.intel.com> References: <20161213155251.28684-1-clemens.gruber@pqgruber.com> <20170118105650.GL18989@ulmo.ba.sec> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170118105650.GL18989@ulmo.ba.sec> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 18, 2017 at 11:56:50AM +0100, Thierry Reding wrote: > On Tue, Dec 13, 2016 at 04:52:50PM +0100, Clemens Gruber wrote: > > When first implementing support for changing the output frequency, an > > optimization was added to continue the PWM after changing the prescaler > > without having to reprogram the ON and OFF registers for the duty cycle, > > in case the duty cycle stayed the same. > > This was flawed, because we compared the absolute value of the duty > > cycle in nanoseconds instead of the ratio to the period. > > > > Fix the problem by removing the shortcut. > > > > Fixes: 01ec8472009c9 ("pwm-pca9685: Support changing the output frequency") > > Cc: # v4.3+ > > Signed-off-by: Clemens Gruber > > --- > > drivers/pwm/pwm-pca9685.c | 11 ----------- > > 1 file changed, 11 deletions(-) > > Mika, Andy, can you guys help review this and 2/2? Looks good to me. Reviewed-by: Mika Westerberg