[Raspberry Pi Original Development] coffeemoney:
Hi maxwen,

first of all, I would love to thank you for this awesome omnirom which works wonderfully on my rPi 4.

I am in a project of my own car which turns the rPi 4 running your version of omni rom and doing mirroring to my car headunit via usb connection so that I can unlock more potential instead of the built in headunit which is locked.

I did some reverse engineer on my headunit console and found out that they are using Google USB accessory protocol (https://developer.android.com/guide/topics/connectivity/usb/accessory) to talk to an Android APP which then triggers the mirroring through USB (ffmpeg).

The usb-c port from rPi can be successfully detected in the headunit console but when the headunit initiate the connection and turn the rPi to usb accessory mode, the rPi restarted. I would like to go into deeper but I am unable to capture any logs from the adb logcat. I am here to seek for your advice or recommendation on getting the logs and to debug on this setup.

Truly appreciate for any input or help given.

p/s : manage to get my log from UART.

[ 48.128250] nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead.
[ 56.921739] Unable to handle kernel write to read-only memory at virtual address 0000000000000700
[ 56.930747] Mem abort info:
[ 56.933578] ESR = 0x96000045
[ 56.936674] EC = 0x25: DABT (current EL), IL = 32 bits
[ 56.942060] SET = 0, FnV = 0
[ 56.945154] EA = 0, S1PTW = 0
[ 56.948334] Data abort info:
[ 56.951251] ISV = 0, ISS = 0x00000045
[ 56.955138] CM = 0, WnR = 1
[ 56.958147] user pgtable: 4k pages, 39-bit VAs, pgdp=00000000f5d02000
[ 56.964680] [0000000000000700] pgd=0000000000000000, pud=0000000000000000
[ 56.971573] Internal error: Oops: 96000045 [#1] PREEMPT SMP
[ 56.977223] Modules linked in:
[ 56.980326] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.85-v8+ #1
[ 56.986682] Hardware name: Raspberry Pi 4 Model B Rev 1.2 (DT)
[ 56.992600] pstate: 60400085 (nZCv daIf +PAN -UAO)
[ 56.997467] pc : acc_ctrlrequest+0xd0/0x4c8
[ 57.001712] lr : android_setup+0xc8/0x13c
[ 57.005775] sp : ffffffc010003be0
[ 57.009133] x29: ffffffc010003be0 x28: 0000000000000000
[ 57.014523] x27: 0000000000000000 x26: 0000000000000000
[ 57.019913] x25: ffffff80f084e2f0 x24: ffffff80f084e2f0
[ 57.025301] x23: 00000000ffffffa1 x22: 0000000000000002
[ 57.030690] x21: ffffff80f5b99480 x20: ffffff80f084e460
[ 57.036078] x19: ffffff80f084e460 x18: 0000000000000000
[ 57.041467] x17: 00000000000257a9 x16: 0000000000000001
[ 57.046854] x15: 0000000000000810 x14: 0000000000000000
[ 57.052243] x13: ffffffffffffffff x12: 00000000ffffa480
[ 57.057631] x11: 0000000000000000 x10: 0000000000000000
[ 57.063019] x9 : ffffffec315020f4 x8 : ffffff80eb4f1c80
[ 57.068408] x7 : 0000000000000000 x6 : ffffff80f5b99488
[ 57.073797] x5 : 0000000000000000 x4 : 0000000000000002
[ 57.079184] x3 : 00020000000033c0 x2 : 0000000000000600
[ 57.084573] x1 : 0000000000000000 x0 : 00000000000000f9
[ 57.089961] Call trace:
[ 57.092441] acc_ctrlrequest+0xd0/0x4c8
[ 57.096330] android_setup+0xc8/0x13c
[ 57.100044] dwc2_hsotg_complete_setup+0xb4/0x7bc
[ 57.104817] usb_gadget_giveback_request+0xb8/0xd0
[ 57.109675] dwc2_hsotg_complete_request+0xdc/0x1b0
[ 57.114623] dwc2_hsotg_handle_outdone+0x374/0x394
[ 57.119481] dwc2_hsotg_epint+0xb20/0xc8c
[ 57.123545] dwc2_hsotg_irq+0x284/0xd80
[ 57.127440] __handle_irq_event_percpu+0xfc/0x274
[ 57.132213] handle_irq_event+0x60/0x124
[ 57.136192] handle_fasteoi_irq+0x128/0x224
[ 57.140434] __handle_domain_irq+0xa0/0xf8
[ 57.144589] gic_handle_irq+0x4c/0xb0
[ 57.148301] el1_irq+0xf4/0x1c0
[ 57.151487] arch_cpu_idle+0x30/0x4c
[ 57.155113] do_idle+0x10c/0x2d0
[ 57.158384] cpu_startup_entry+0x24/0x28
[ 57.162363] rest_init+0xcc/0xd8
[ 57.165637] arch_call_rest_init+0x10/0x18
[ 57.169791] start_kernel+0x328/0x39c
[ 57.173515] Code: 2a1f03e1 79000116 f9400668 f9001909 (f903835f)
[ 57.179697] ---[ end trace fb93814e9420f57a ]---
[ 57.184378] Kernel panic - not syncing: Fatal exception in interrupt
[ 57.190828] SMP: stopping secondary CPUs
[ 57.194813] Kernel Offset: 0x2c20c00000 from 0xffffffc010000000
[ 57.200816] PHYS_OFFSET: 0xffffffde40000000
[ 57.205057] CPU features: 0x00000002,20806000
[ 57.209473] Memory Limit: none
[ 57.212577] Rebooting in 5 seconds..

Thank you. :)