On Fri, Aug 08, 2014 at 09:55:43AM +0000, Peter Chan wrote: > I have a question about the wm8962 mono speaker mode. In SPK_MONO description > at table 73, it says "When SPK_MONO is enabled, both speakers output the > signal from the left channel". Does it mean only the left channel control the > output in mono speaker mode? > > Thanks, > Peter > > -----Original Message----- > From: Nicolin Chen [mailto:guangyu.c...@freescale.com] > Sent: Friday, August 08, 2014 4:21 PM > To: Mark Brown > Cc: Nicolin Chen; alsa-de...@alsa-project.org; ti...@suse.de; > patc...@opensource.wolfsonmicro.com; Wang Shengjiu-B02247; > lgirdw...@gmail.com; linux-kernel@vger.kernel.org; CHAN Peter-B18700; > ckee...@opensource.wolfsonmicro.com; r...@opensource.wolfsonmicro.com > Subject: Re: [alsa-devel] [PATCH] ASoC: wm8962: Correct the bit offset to > enable mono speaker output > > On Thu, Aug 07, 2014 at 05:58:36PM +0100, Mark Brown wrote: > > On Thu, Aug 07, 2014 at 07:55:49PM +0800, Nicolin Chen wrote: > > > As WM8962 datasheet describes for SPK_MONO bit of R51: When SPK_MONO > > > is set to '1', both speakers output the signal from the left channel. > > > > > So for mono speaker widget, we shall enable Left Channel whose > > > enable bit is 6 instead of 7 (Right Channel). > > > > > > This patches just simply corrects the bit offset. > > > > > spkmixl, ARRAY_SIZE(spkmixl)), SND_SOC_DAPM_MUX_E("Speaker > > > PGA", WM8962_PWR_MGMT_2, 4, 0, &spkoutl_mux, > > > out_pga_event, SND_SOC_DAPM_POST_PMU), > > > -SND_SOC_DAPM_PGA("Speaker Output", WM8962_CLASS_D_CONTROL_1, 7, 0, > > > NULL, 0), > > > +SND_SOC_DAPM_PGA("Speaker Output", WM8962_CLASS_D_CONTROL_1, 6, 0, > > > +NULL, 0), > > > SND_SOC_DAPM_OUTPUT("SPKOUT"), > > > }; > > > > Someone who's name I'd need to look up submitted an identical fix off > > list recently - I checked the datasheet and it seems that in mono mode > > the speaker output actually wants both left and right channels active > > so there is a bug here but this isn't the fix. > > I rechecked the datasheet and found that the hardware needs to tie both > outputs and enable both bits. So the patch should be invalid. > > But our customer reported that they did try to set both SPKOUTR_ENA and > SPKOUTL_ENA bits in mono mode but the sound is lousy. If setting SPKOUTR_ENA > alone, the speaker has no sound. Only setting SPKOUTL_ENA bit get the correct > speaker output in mono mode.
>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. Thanks, Charles -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
