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[PATCH 0/6] ASoC: sgtl5000: fix use of regulators and internal LDO

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  [PATCH 0/6] ASoC: sgtl5000: fix use of regulators and internal LDO Clemens Gruber <clemens.gruber@pqgruber.com> - 2016-06-07 01:20 +0200
    Re: [PATCH 0/6] ASoC: sgtl5000: fix use of regulators and internal  LDO Eric Nelson <eric@nelint.com> - 2016-06-07 12:50 +0200

#1415570 — [PATCH 0/6] ASoC: sgtl5000: fix use of regulators and internal LDO

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]

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(-)

-- 
2.8.3

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#1415979 — Re: [PATCH 0/6] ASoC: sgtl5000: fix use of regulators and internal LDO

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(-)
> 

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