RE: usb: gadget: dwc2: not getting audio data

Minas Harutyunyan
2022-12-16T07:03:28Z

Hi Palak,

On 12/16/2022 1:16 AM, Palak SHAH wrote:
>From: Palak SHAH <palak.shah@raritan.com>
>Sent: Friday, December 16, 2022 1:16 AM
>To: Minas Harutyunyan <hminas@synopsys.com>; Maynard CABIENTE
><maynard.cabiente@raritan.com>
>Cc: linux-usb@vger.kernel.org
>Subject: RE: usb: gadget: dwc2: not getting audio data
>
>Hi Minas,
>Please find attached the logs I got after I applied your latest patch.
>
>Thanks,
>Palak
>

In last log I don't see any obvious issue besides suspicious 6 second time gap after
last ep1out transfer complete and control requests from host on getting string device
descriptors. Could you please explain why this time gap happen? Do you stop playing
from host side? If no, then it's looks like your platform issue - interrupts from
core doesn't achieve driver.
Driver is interrupt driven SW and can't work correctly if interrupts not asserted or
not passed to driver.

Same type of time gaps (not asserted interrupts) seen in previous logs too:
1. KX4-101_2022-12-06T16_00_38.039Z.txt, 2 seconds:

[ 182.154799] dwc2 ffb40000.usb: ureq->length:6 ureq->actual:0
[ 184.940357] dwc2 ffb40000.usb: dwc2_hsotg_irq: daint=00020000

2. KX4-101_2022-12-09T16_41_45.579Z.txt, 3 seconds:

[ 2847.681630] dwc2 ffb40000.usb: ep1out: req 307d375f: 200@3a5638aa, noi=0, zero=0, snok=0
[ 2850.442440] dwc2 ffb40000.usb: dwc2_hsotg_irq: 0428c0b8 00080000 (d08c3c44) retry 8

3. KX4-101_2022-12-12T16_46_16.365Z.txt, 7 seconds:

[ 504.335408] dwc2 ffb40000.usb: dwc2_gadget_complete_isoc_request_ddma: compl_desc # 18
[ 511.068368] dwc2 ffb40000.usb: dwc2_hsotg_irq: 0428c038 00080000 (d08c3cc4) retry 8

4. KX4-101_2022-12-15T21_14_35.964Z.txt, 6 seconds:

[ 83.796195] dwc2 ffb40000.usb: dwc2_gadget_complete_isoc_request_ddma: compl_desc # 12
[ 89.817700] dwc2 ffb40000.usb: dwc2_hsotg_start_req: 0ed84000 pad => 0x00000b14

I would recommend you to investigate your platform to find out reason of these
time gaps.

Thanks,
Minas