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@kernel.org] Sent: Wednesday, August 13, 2014 5:58 AM To: Charles Keepax Cc: CHAN Peter-B18700; alsa-devel@alsa-project.org; tiwai@suse.de; linux-kernel@vger.kernel.org; patches@opensource.wolfsonmicro.com; Wang Shengjiu-B02247; lgirdwood@gmail.com; Nicolin Chen; Chen Guangyu-B42378; rf@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?