WL1837 PCM Kernel/DTS configuration for i.MX board and HSP/HFP over HCI

Brandon Schaefer

Other Parts Discussed in Thread: WL1837

I have bluetooth functioning with bluez 5.40, pulseaudio 6.0, and TIInit_11.8.32 as BTS. A2DP profile works fine and can send audio to an a2dp sink. My issue arises when I try to use HSP/HFP profiles. I followed recommendations from here to have HSP/HFP communicate over HCI, but it sounds terrible (slower frequency/metallic.. almost like slow-mo)

question 1) Proper way to get PCM lines working on an i.MX7 board, any other helpful hints or someone who's already done this?

I'm currently attempting to follow the patch for EVM to enable PCM wiki,..

This is my main goal since its the recommended way to use HSP/HFP.

question 2 ) Is there anything that I can do to fix HSP/HFP over HCI? I imagine its something to do with the sampling rate.

NOTE: The second command from the link I posted causes kernel print statements Bluetooth: Unknown type 2 conn a8c72800

Have yet to attempt the solutions here as I'm working on PCM.. also no resolution besides ask bluez why it fails to recognize eSCO packets.

Thanks you very much!

over 8 years ago

0 Eyal Reizer over 8 years ago

TI__Mastermind 20285 points

Hello,

your question has been assigned to the relevant POC.

BR,
Eyal

0 Brandon Schaefer over 8 years ago in reply to Eyal Reizer

Intellectual 290 points

Thanks, also I never clarified that the processor is specifically the i.MX7 Dual.

0 Brandon Schaefer over 8 years ago in reply to Eyal Reizer

Intellectual 290 points

Hello Eyal,

Any updates from the relevant POC for this question?

Thanks,

Brandon

0 Vihang Parmar over 8 years ago in reply to Brandon Schaefer

TI__Mastermind 29301 points

Hi Brandon,

Sorry for the delay.

1) You can use AM335x-EVM and AM437x-EVM dts configuration for PCM as example. processors.wiki.ti.com/index.php

2) The SCO connection data over HCI for the HSP/HFP is not expected to be as good as the PCM. Moreover, the SCO data over HCI is not supported and not a recommended way to implement HSP/HFP.

Hope this helps with your main goal.

Best regards,
Vihang

0 Brandon Schaefer over 8 years ago in reply to Vihang Parmar

Intellectual 290 points

I noticed this patch has the wl1837 as the slave device. Default BTS codec config sets up wl1837 as the master device.
Were there other changes via HCI VS commands that go along with this patch I should be made aware of?

EDIT: By changes, I mean compared to TIInit_11.8.32.bts script. I have audio over PCM semi-working, sample rates seem off. Looking into codec config vs. driver config to see if there's anything...

Thanks,

Brandon

Wi-Fi

Wi-Fi forum

WL1837 PCM Kernel/DTS configuration for i.MX board and HSP/HFP over HCI