Re: [PATCH] ASoC: es8316: limit headphone mixer volume

From: Katsuhiro Suzuki
Date: Mon Aug 26 2019 - 05:01:16 EST


Oops... I got mistake,

> SOC_DOUBLE_TLV("Headphone Mixer Volume", ES8316_HPMIX_VOL,
> 0, 4, 15, 0, hpmixer_gain_tlv),

is wrong,

> SOC_DOUBLE_TLV("Headphone Mixer Volume", ES8316_HPMIX_VOL,
> 0, 4, 11, 0, hpmixer_gain_tlv),

is correct.

Best Regards,
Katsuhiro Suzuki

On 2019/08/26 17:41, Katsuhiro Suzuki wrote:
Hello Daniel,

On 2019/08/26 11:53, Daniel Drake wrote:
On Mon, Aug 26, 2019 at 1:38 AM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
On 24-08-19 23:04, Katsuhiro Suzuki wrote:
This patch limits Headphone mixer volume to 4 from 7.
Because output sound suddenly becomes very loudly with many noise if
set volume over 4.

That sounds like something that should be limited in UCM.

Higher then 4 not working matches my experience, see this comment from
the UCM file: alsa-lib/src/conf/ucm/codecs/es8316/EnableSeq.conf :

# Set HP mixer vol to -6 dB (4/7) louder does not work
cset "name='Headphone Mixer Volume' 4"

What does "does not work" mean more precisely?

I checked the spec, there is indeed something wrong in the kernel driver here.
The db scale is not a simple scale as the kernel source suggests.

Instead it is:
0000 â -12dB
0001 â -10.5dB
0010 â -9dB
0011 â -7.5dB
0100 â -6dB
1000 â -4.5dB
1001 â -3dB
1010 â -1.5dB
1011 â 0dB

> So perhaps we can fix the kernel to follow this table and then use UCM
> to limit the volume if its too high on a given platform?

Thank you very important information. So you mean value 5, 6, 7 are
illegal settings for ES8316. Correct codes are

static const SNDRV_CTL_TLVD_DECLARE_DB_RANGE(hpmixer_gain_tlv,
ÂÂÂÂ0, 4, TLV_DB_SCALE_ITEM(-1200, 150, 0),
ÂÂÂÂ8, 11, TLV_DB_SCALE_ITEM(-450, 150, 0),


ÂÂÂÂSOC_DOUBLE_TLV("Headphone Mixer Volume", ES8316_HPMIX_VOL,
ÂÂÂÂÂÂÂÂÂÂÂÂÂÂ 0, 4, 15, 0, hpmixer_gain_tlv),

Is my understanding correct? If so I'll test it on my board
(RockPro64) and re-send patch.

BTW, do you know how to get ES8316 I2C registers spec?
I want to see it for understanding current code, but I cannot find...


Best Regards,
Katsuhiro Suzuki