Add Bluetooth USB ID 0489:e156 (HP EliteMini, MT6639/MT7902)

[majkm4]

Add Bluetooth USB ID 0489:e156 (HP EliteMini, MT6639/MT7902)

Hardware

• Device: HP EliteMini (system-product-name reports "EliteMini Series")
• Bluetooth USB ID: 0489:e156 (Foxconn/Hon Hai), iManufacturer reports "MediaTek Inc.", iProduct "Wireless_Device"
• WiFi: MT7902 (PCI side), working out of the box with this package
• Kernel: 7.0.0-14-generic (Ubuntu 26.04)

Problem

With the stock device table, btusb enumerates the device but the controller
never responds to the initial HCI Reset command:

Bluetooth: hci0: Opcode 0x0c03 failed: -110

No firmware download is attempted (no btmtk/patch/firmware lines in dmesg),
and hciconfig shows BD Address: 00:00:00:00:00:00, DOWN.

lsusb -v confirms a standard 3-interface BT layout (ACL/SCO/ISO,
class 224/1/1, Wireless/RF/Bluetooth) — same shape as the other
supported boards, just a different PID.

Fix

Adding 0xe156 to the device tables in btmtk.c and btusb.c (same pattern
as the existing entries for 0xe13a, 0xe0fa, 0xe10f, 0xe110, 0xe116) resolves
it completely. After rebuilding with DKMS:

Bluetooth: hci0: HW/SW Version: 0x008a008a, Build Time: 20250826211444
Bluetooth: hci0: Device setup in 235725 usecs
Bluetooth: hci0: AOSP extensions version v0.96

hciconfig -a now shows a valid BD Address, UP RUNNING, Manufacturer:
MediaTek, Inc. (70). Bluetooth scanning/pairing works normally afterward.

btmtk.c — btmtk_mt6639_devs[]

	{ 0x0489, 0xe156 },	/* HP EliteMini */

btusb.c — device ID table

	{ USB_DEVICE(0x0489, 0xe156), .driver_info = BTUSB_MEDIATEK |
						     BTUSB_WIDEBAND_SPEECH },

[jetm]

Done, 0489:e156 ships in v2.12-1. It's in the btusb quirks table now (so it's handled as MediaTek rather than the generic Broadcom match) and in the MT6639 device list. Update from the AUR or install the v2.12-1 RPM/DEB. Thanks for the complete report and the tested diff, it made this trivial.