Bug 218992

Summary:	Usb Type-C headset TX is noise
Product:	Drivers	Reporter:	Udipto (quic_ugoswami)
Component:	USB	Assignee:	Default virtual assignee for Drivers/USB (drivers_usb)
Status:	NEW ---
Severity:	normal
Priority:	P3
Hardware:	ARM
OS:	Linux
Kernel Version:		Subsystem:
Regression:	No	Bisected commit-id:

Description Udipto 2024-06-27 10:04:46 UTC

I'm encountering an issue where the USB audio is transmitted in noise instead of valid data. This was found on SM8650.

Steps to reproduce are as follows:
1. Start Connect USB type-c headset.
2. Start the Karaoke with USB-headset
Result:

Comment 1 Udipto 2024-06-27 10:11:41 UTC

The issue only happened one specific USB-headphone that it supports 44.1k to capture.  

The log:

<6>[316.777381] [pid:    22] usb 1-1: new high-speed USB device number 2 using xhci-hcd
<6>[316.918353] [pid:    22] usb 1-1: New USB device found, idVendor=0424, idProduct=2422, bcdDevice= 0.a0
<6>[316.918382] [pid:    22] usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
<6>[318.229277] [pid:  1921] usb 1-1.1: new high-speed USB device number 3 using xhci-hcd
<6>[318.326969] [pid:  1921] usb 1-1.1: New USB device found, idVendor=0499, idProduct=170d, bcdDevice= 1.10
<6>[318.327014] [pid:  1921] usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
<6>[318.327048] [pid:  1921] usb 1-1.1: Product: AG06/AG03
<6>[318.327079] [pid:  1921] usb 1-1.1: Manufacturer: Yamaha Corporation


05-13 19:43:47.220  root     8     8 E usb 1-1.1: Mismatched sample rate 48000 vs 44100 for EP 0x82

Is coming up on dmesg.


This is the audio card info of the headset:
USB audio card info:
proc/asound/card1 # cat stream0
Yamaha Corporation AG06/AG03 at usb-xhci-hcd.2.auto-1.1, high speed : USB Audio
 
Playback:
 Status: Stop
 Interface 1
  Altset 1
  Format: S32_LE
  Channels: 2
  Endpoint: 0x01 (1 OUT) (ASYNC)
  Rates: 44100, 48000, 88200, 96000, 176400, 192000
  Data packet interval: 125 us
  Bits: 24
  Channel map: FL FR
  Sync Endpoint: 0x81 (1 IN)
  Sync EP Interface: 1
  Sync EP Altset: 1
  Implicit Feedback Mode: No
 
Capture:
 Status: Stop
 Interface 2
  Altset 1
  Format: S32_LE
  Channels: 2
  Endpoint: 0x82 (2 IN) (ASYNC)
  Rates: 44100, 48000, 88200, 96000, 176400, 192000
  Data packet interval: 125 us
  Bits: 24
  Channel map: FL FR

Comment 2 Udipto 2024-06-27 10:24:48 UTC

One more info:

Looking at endpoint.c code I think the function snd_usb_endpoint_open extracts the ep->clock_ref using clock_ref_find(chip, fp->clock) and this remains same for all endpoints available.

In the issue case when the error mismatch sample rate comes up, looks like the ep->clock_ref->opened is 2, and it will not decrease to 0 when we close EP 0x82 because EP 0x1 is opened. Also the clock_ref->rate will not go to 0 when close EP 0x82.

Comment 3 Udipto 2024-06-27 10:25:14 UTC

One more info:

Looking at endpoint.c code I think the function snd_usb_endpoint_open extracts the ep->clock_ref using clock_ref_find(chip, fp->clock) and this remains same for all endpoints available.

In the issue case when the error mismatch sample rate comes up, looks like the ep->clock_ref->opened is 2, and it will not decrease to 0 when we close EP 0x82 because EP 0x1 is opened. Also the clock_ref->rate will not go to 0 when close EP 0x82.