[alsa-devel] [PATCH 1/5] ASoC: rt5645: Prevent the pop sound of the headphone while rebooting or shutdowning

[Oder Chiou]

> -----Original Message-----
> From: Mark Brown [mailto:broonie at kernel.org]
> Sent: Wednesday, August 26, 2015 1:57 AM
> To: Oder Chiou
> Cc: lgirdwood at gmail.com; alsa-devel at alsa-project.org; Flove; Bard Liao; John Lin;
> woojoo.lee at samsung.com
> Subject: Re: [PATCH 1/5] ASoC: rt5645: Prevent the pop sound of the headphone
> while rebooting or shutdowning
> 
> On Mon, Aug 24, 2015 at 08:32:55PM +0800, Oder Chiou wrote:
> > Add i2c shutdown function to prevent the pop sound of the headphone
> > while the system is rebooting or shutdowning
> 
> > +	regmap_update_bits(rt5645->regmap, RT5645_GEN_CTRL3, 0x0020, 0x0020);
> > +	regmap_update_bits(rt5645->regmap, RT5645_IN1_CTRL2, 0x1000, 0x1000);
> > +	regmap_update_bits(rt5645->regmap, RT5645_IN1_CTRL1, 0x0004,
> > +0x0000);
> 
> Yay, magic numbers!  What is the issue this is fixing?  The core is supposed to
> power everything down to _BIAS_OFF before exiting, are we missing something
> here?
> 
It de-initialed our jack detection function, and it cannot be turned off in
_BIAS_OFF. If we didn't de-initial it, we will hear the pop sound in the
situation of powering off, thanks.