[alsa-devel] [PATCH] ASoC: wm8962: Correct the bit offset to enable mono speaker output

[Peter Chan]

I found that in mono speaker mode, only the left channel is enable. The SPKOUTR_PGA_ENA bit remains 0 in this case. Thus when SPKOUTR_ENA is set, poor sound quality results.

-----Original Message-----
From: Mark Brown [mailto:broonie at kernel.org] 
Sent: Wednesday, August 13, 2014 5:58 AM
To: Charles Keepax
Cc: CHAN Peter-B18700; alsa-devel at alsa-project.org; tiwai at suse.de; linux-kernel at vger.kernel.org; patches at opensource.wolfsonmicro.com; Wang Shengjiu-B02247; lgirdwood at gmail.com; Nicolin Chen; Chen Guangyu-B42378; rf at opensource.wolfsonmicro.com
Subject: Re: [alsa-devel] [PATCH] ASoC: wm8962: Correct the bit offset to enable mono speaker output

On Tue, Aug 12, 2014 at 09:24:16AM +0100, Charles Keepax wrote:
> On Mon, Aug 11, 2014 at 02:19:49PM +0100, Charles Keepax wrote:

> > From the wording of "tie both outputs together" in the datasheet I 
> > would assume that means both should be fed the same audio? Was this 
> > done? I will try to give the hardware guys here a shout and see if I 
> > can get some clarification on mono mode on this device.

> I have had a word with the hardware team here and both channels do 
> need to be enabled but audio should only be fed to the left channel. 
> So the driver definitely needs updated for the mono case, but I am 
> unclear as to what is causing your poor audio quality issue.

Overdriving the speaker perhaps?