[BUG] rtw89: RTL8852CE RX_DCK timeout + Bluetooth A2DP coexistence failures (fw-2.bin 0.27.129.4)

[or1k <tixzit@gmail.com>]

Hi,

Reporting a Wi-Fi/Bluetooth coexistence issue on RTL8852CE that also has an
open Fedora/Red Hat tracker (bugzilla.redhat.com #2349675), but that report
was filed against an older firmware (rtw8852c_fw-1.bin, 0.27.97.0). I'm
seeing what looks like the same class of failure on the newer
rtw8852c_fw-2.bin, firmware version 0.27.129.4 (3f1a5302), so it may not be
fully fixed by whatever changed between those firmware revisions.

Hardware:
  Wi-Fi:      Realtek RTL8852CE [10ec:c852] rev 01, Lenovo subsystem 
[17aa:5852]
              PCI 0000:02:00.0, driver rtw89_8852ce
  Bluetooth:  same combo chip, USB 0bda:5852 "Realtek Bluetooth Radio",
              driver btusb/btrtl, BT firmware rtl8852cu_fw_v2.bin (0x040d7225)
  Platform:   Lenovo laptop, AMD Ryzen APU (unrelated to this bug, just for
              context — ruled out as a factor)

Software:
  Kernel 7.1.3-200.fc44.x86_64 (Fedora 44), linux-firmware-20260622-1.fc44

Symptom: intermittent Wi-Fi disconnects/reauth together with Bluetooth A2DP
audio transport failures, both traced to the same physical combo chip.

dmesg (Wi-Fi side), recurring several times/day in short clusters:

  rtw89_8852ce 0000:02:00.0: [RX_DCK] S1 RXDCK timeout
  rtw89_8852ce 0000:02:00.0: timed out to flush queues

journalctl (Bluetooth side), same time frame, device 85:42:36:51:B1:D1
(Bluetooth headphones, A2DP sink):

  wireplumber: spa.bluez5.sink.media: Misscket
    (0 suppressed): Bluetooth adapter firm
  bluetoothd: src/profile.c:ext_io_disconn for
    Hands-Free Voice gateway: getpeername:
    connected (107)
  wireplumber: spa.bluez5: Failure in Bluetooth audio transport
    /org/bluez/hci0/dev_85_42_36_51_B1_D1/

Direct correlation captured with mtr: a WireGuard-tunneled ping test
(ultimately routed over wlp2s0) showed 5.9 the
same ~60s window as 8 consecutive "Missingines
for the same device (00:12:51) and an HFP 1).
Both radios degraded together, which pointmware
fault rather than two unrelated bugs.

Workarounds tried, partial effect only:
  - USB autosuspend disabled for the BT ad
  - rtw89_core.disable_ps_mode=1, rtw89_pc
  - A2DP codec forced to SBC instead of AA

Is this expected to be covered by the same fix path as RH#2349675, or is it
worth tracking separately since it reprodu?
Happy to test candidate firmware/patches o

Thanks,
Oleh