[alsa-devel] Cherry Trail + RT5645 devices with a mono speaker ?

[Bard Liao]

> -----Original Message-----
> From: Hans de Goede [mailto:hdegoede at redhat.com]
> Sent: Friday, October 27, 2017 6:18 PM
> To: Bard Liao; Pierre-Louis Bossart
> Cc: alsa-devel at alsa-project.org; Oder Chiou; Shuming [范書銘]; Albert Chen
> Subject: Re: Cherry Trail + RT5645 devices with a mono speaker ?
> 
> >>
> >> On 16-10-17 13:31, Bard Liao wrote:
> >>>> -----Original Message-----
> >>>> From: Hans de Goede [mailto:hdegoede at redhat.com]
> >>>> Sent: Sunday, October 15, 2017 2:12 AM
> >>>> To: Pierre-Louis Bossart; Bard Liao
> >>>> Cc: alsa-devel at alsa-project.org
> >>>> Subject: Cherry Trail + RT5645 devices with a mono speaker ?
> >>>>
> >>>> Hi Pierre-Louis, Bard,
> >>>>
> >>>> I've been looking into getting some Cherry Trail + RT5645
> >>>> devices with a mono speaker I have to work properly.
> >>>>
> >>>> Specifically the goal is to mix the right channel into
> >>>> the left output, so that sounds which are only played
> >>>> over the right channel do not get lost.
> >>>>
> >>>> I'm using this UCM file:
> >>>> https://github.com/plbossart/UCM/blob/master/byt-rt5640/HiFi
> >>>>
> >>>> Looking at the rtl5640 UCM file, getting the mono speaker
> >>>> to work (in a first simple attempt) should be as simple
> >>>> as replacing:
> >>>>
> >>>>                    cset "name='SPOR MIX SPKVOL R Switch' on"
> >>>>
> >>>> With
> >>>>
> >>>>                    cset "name='SPOL MIX SPKVOL R Switch' on"
> >>>>
> >>>> But this does not work, the speaker test sound for the
> >>>> right speaker is still silent (works with headphones).
> >>>>
> >>>> I've also looked into directly poking the
> >>>> RT5645_SPO_MIXER i2c register for testing, but when
> >>>> checking its value with the original unmodified UCM
> >>>> file:
> >>>>
> >>>> [root at localhost ~]# i2cget -y -f 1 0x1a 0x48  w
> >>>> 0x06c8
> >>>>
> >>>> That is: 0xc806 as the output of i2cget "w" mode
> >>>> needs byteswapping. Note that both the
> >>>> RT5645_M_SV_L_SPM_L and RT5645_M_SV_R_SPM_L bits
> >>>> are already cleared, which is weird as this is
> >>>> before I've modified anything. Also the
> >>>> RT5645_M_SV_R_SPM_R bit is cleared, but that is
> >>>> expected.
> >>>>
> >>>> Even if I manually set reg 0x48 to 0x07c8 which AFAIK
> >>>> should enable output of both left and right channels
> >>>> on the left speaker I still only get sounds played
> >>>> on the left channel.
> >>>>
> >>>> Any insights / help with this would be very much
> >>>> welcome.
> >>>

Unfortunately, "SPOL MIX DAC R1 Switch" and "SPOL MIX SPKVOL R Switch"
are no longer valid. I will send a patch for that. Please use
"Stereo DAC MIXL DAC R1 Switch" to do L/R channel mix.

> 
> Regards,
> 
> Hans
> 
> ------Please consider the environment before printing this e-mail.