USB doesn't revert after unpairing BLE

[mondalaci]

1. I pair my Android phone via BLE. The UHK works fine via BLE.
2. I unpair my phone.
3. The UHK doesn't work via USB, so I must reboot the right half. In the Zephyr console, I can see that the HID app has been stopped. This used to work.

A bisect revealed that the offending commit is 48c69e0.

[kareltucek]

. In the Zephyr console, I can see that the HID app has been stopped.

Eh? What or how can you see that?

[mondalaci]

Reading hardware config
Reading user config
Applying user config
User config applied
I: 3 Sectors of 4096 bytes
I: alloc wra: 0, f40
I: data wra: 0, 210
I: SoftDevice Controller build revision: 
I: 36 f0 e5 0e 87 68 48 fb |6....hH.
I: 02 fd 9f 82 cc 32 e5 7b |.....2.{
I: 91 b1 5c ed             |..\.    
I: HW Platform: Nordic Semiconductor (0x0002)
I: HW Variant: nRF52x (0x0002)
I: Firmware: Standard Bluetooth controller (0x00) Version 54.58864 Build 1214809870
I: No ID address. App must call settings_load()
Settings: Found peer 'left' with address 22ef8a977df4
I: Identity: EA:5C:DD:BC:10:F4 (random)
I: HCI: version 5.4 (0x0d) revision 0x118f, manufacturer 0x0059
I: LMP: version 5.4 (0x0d) subver 0x118f
NUS and HID advertising successfully started
Scan module initialized
NUS Client module initialized
Scanning successfully started
Filters matched: left (f4:7d:97:8a:ef:22), connectable:1
Scan connecting: left (f4:7d:97:8a:ef:22)
Filters matched: left (f4:7d:97:8a:ef:22), connectable:0
Connecting failed: left (f4:7d:97:8a:ef:22)
uhk80:right$ Connected to left (f4:7d:97:8a:ef:22)
MTU exchange done with left (f4:7d:97:8a:ef:22)
Security changed: left (f4:7d:97:8a:ef:22), level 4
Resetting left right link! Bidirectional
Service discovery completed
Connected to unknown (ac:d6:18:1b:3d:b5)
Passkey for unknown (ac:d6:18:1b:3d:b5): 794533
Type `uhk btacc 1/0` to accept/reject
BLE HID conn params: interval=11 ms, latency=10, timeout=1000 ms
Numeric Match, conn 0x2000ce08
Security changed: unknown (ac:d6:18:1b:3d:b5), level 4
Pairing completed: unknown (ac:d6:18:1b:3d:b5), bonded 1
BLE HID conn params: interval=7 ms, latency=0, timeout=5000 ms
BLE HID conn params: interval=11 ms, latency=10, timeout=1000 ms
I: starting HID app 1: 1
I: input report sent (size 10)
I: input report sent (size 10)
I: input report sent (size 10)
I: input report sent (size 10)
I: input report sent (size 10)
Disconnected from unknown (ac:d6:18:1b:3d:b5), reason 19
NUS and HID advertising successfully started
I: stopping HID app 1

It's worth mentioning that Zephyr crashes at the first BLE connection attempt and it only works afterward. I can do another bisect regarding the initial crash if justified.

[kareltucek]

Well, I am getting that "stopping HID" log even with the "good" commits, and UHK continues to work just fine. I suspect it refers to bluetooth hid or something.

Given the indicated commit, it seems to be just a minor problem, as in that particular commit, usb state is initialized to "disconnected", but the power-delegate is not yet implemented, so upon disconnecting HID, uhk enters sleep mode in the old locking variant.

---

I didn't manage to reproduce this on master just now (4fb3c97).

Also, I am not experiencing any Zephyr crash on a BLE connection attempt.

[mondalaci]

As it turns out, this issue is not always reproducible. The relevant Zephyr log:

I: input report sent (size 10)
Disconnected from unknown (ac:d6:18:1b:3d:b5), reason 19
NUS and HID advertising successfully started
I: stopping HID app 1
L2 Suspend
L0 ON

Sometimes, the keyboard and mouse interface keep working despite the stopping HID app 1 message, but usually, the mouse interface doesn't work anymore when switching from my Android phone (BLE) to USB.

Closing this issue in favor of UltimateHackingKeyboard/firmware80#310.