From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Nelson Subject: Re: [PATCH 0/6] ASoC: sgtl5000: fix use of regulators and internal LDO Date: Tue, 7 Jun 2016 12:49:23 +0200 Message-ID: <5756A6B3.3030601@nelint.com> References: <20160606231453.19377-1-clemens.gruber@pqgruber.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160606231453.19377-1-clemens.gruber@pqgruber.com> Sender: linux-kernel-owner@vger.kernel.org To: Clemens Gruber , alsa-devel@alsa-project.org Cc: Mark Brown , Fabio Estevam , linux-kernel@vger.kernel.org List-Id: alsa-devel@alsa-project.org Thanks for taking this up Clemens. On 06/07/2016 01:14 AM, Clemens Gruber wrote: > This patch set addresses a structural problem in the handling of > regulators for VDDIO, VDDA, and VDDD in the SGTL5000 driver. > > The first two of these power rails must be powered on prior to any I2C > communication, and yet the regulators were tied to the codec, which is > instantiated only after a fair amount of I2C communication takes place. > > In other words, these regulators could never have function, and we can > surmise that no user of this driver has switched power supply rails > connected to them. > > The third power rail (VDDD) can be derived internally (by using I2C > registers) though the data sheet says that if an external VDDD is used, > it should be enabled before MCLK is started and I2C activity begins. > > [I rebased Eric's patches from Feb 2015, fixed a few warnings, URLs, > etc. and squashed two patches into one. - Clemens] > Thanks also for fixing up my e-mail address (since I'm no longer at Boundary Devices). > Clemens Gruber (1): > ASoC: sgtl5000: Remove misleading comment > > Eric Nelson (5): > ASoC: sgtl5000: Fix regulator support > ASoC: sgtl5000: Write all default registers > ASoC: sgtl5000: Initialize CHIP_ANA_POWER to power-on defaults > ASoC: sgtl5000: Disable internal PLL early > ASoC: sgtl5000: Do not disable regulators in SND_SOC_BIAS_OFF > > sound/soc/codecs/sgtl5000.c | 421 +++++++++++--------------------------------- > sound/soc/codecs/sgtl5000.h | 2 + > 2 files changed, 102 insertions(+), 321 deletions(-) >