From: Chris Lu chris.lu@mediatek.com
[ Upstream commit 5a6700a31c953af9a17a7e2681335f31d922614d ]
Add VID 0489 & PID e170 for MediaTek MT7922 USB Bluetooth chip.
The information in /sys/kernel/debug/usb/devices about the Bluetooth device is listed as the below.
T: Bus=06 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=480 MxCh= 0 D: Ver= 2.10 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs= 1 P: Vendor=0489 ProdID=e170 Rev= 1.00 S: Manufacturer=MediaTek Inc. S: Product=Wireless_Device S: SerialNumber=000000000 C:* #Ifs= 3 Cfg#= 1 Atr=e0 MxPwr=100mA A: FirstIf#= 0 IfCount= 3 Cls=e0(wlcon) Sub=01 Prot=01 I:* If#= 0 Alt= 0 #EPs= 3 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb E: Ad=81(I) Atr=03(Int.) MxPS= 16 Ivl=125us E: Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms I:* If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 0 Ivl=1ms I: If#= 1 Alt= 1 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 9 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 9 Ivl=1ms I: If#= 1 Alt= 2 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 17 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 17 Ivl=1ms I: If#= 1 Alt= 3 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 25 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 25 Ivl=1ms I: If#= 1 Alt= 4 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 33 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 33 Ivl=1ms I: If#= 1 Alt= 5 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 49 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 49 Ivl=1ms I: If#= 1 Alt= 6 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 63 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 63 Ivl=1ms I:* If#= 2 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=(none) E: Ad=8a(I) Atr=03(Int.) MxPS= 64 Ivl=125us E: Ad=0a(O) Atr=03(Int.) MxPS= 64 Ivl=125us I: If#= 2 Alt= 1 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=(none) E: Ad=8a(I) Atr=03(Int.) MxPS= 512 Ivl=125us E: Ad=0a(O) Atr=03(Int.) MxPS= 512 Ivl=125us
Signed-off-by: Chris Lu chris.lu@mediatek.com Reviewed-by: Paul Menzel pmenzel@molgen.mpg.de Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Signed-off-by: Sasha Levin sashal@kernel.org ---
LLM Generated explanations, may be completely bogus:
## Analysis: Bluetooth: btusb: MT7922: Add VID/PID 0489/e170
### 1. COMMIT MESSAGE ANALYSIS
**Subject**: Adding a new USB Vendor ID (VID) 0x0489 and Product ID (PID) 0xe170 for a MediaTek MT7922 Bluetooth chip.
**Key Tags**: - Signed-off-by: Chris Lu from MediaTek (the chip vendor) - Reviewed-by: Paul Menzel - Signed-off-by: Luiz Augusto von Dentz (Bluetooth maintainer)
No explicit `Cc: stable@vger.kernel.org` tag, but this is common for device ID additions which are often handled implicitly.
### 2. CODE CHANGE ANALYSIS
The change is a 2-line addition to the `quirks_table[]` array: ```c { USB_DEVICE(0x0489, 0xe170), .driver_info = BTUSB_MEDIATEK | BTUSB_WIDEBAND_SPEECH }, ```
This simply registers a new USB device ID with existing driver flags (`BTUSB_MEDIATEK` and `BTUSB_WIDEBAND_SPEECH`) that are already fully supported. The btusb driver already contains full MT7922 support - this just adds another VID/PID variant to the recognition table.
### 3. CLASSIFICATION
This is a **NEW DEVICE ID** addition - one of the explicitly allowed exception categories for stable backports: - Adding a USB VID/PID to an existing, well-tested driver - Trivial one-entry addition to a device table - The driver code for MT7922 already exists; only recognition is missing
### 4. SCOPE AND RISK ASSESSMENT
| Metric | Assessment | |--------|------------| | Lines changed | 2 | | Files touched | 1 | | Complexity | Minimal - static table entry | | Risk | **Extremely low** |
The change can only affect USB devices with VID=0x0489 and PID=0xe170. Users without this specific hardware are completely unaffected. This is about as low-risk as a kernel patch can be.
### 5. USER IMPACT
- **Affected users**: Those with this specific MediaTek MT7922 Bluetooth variant - **Severity without fix**: Bluetooth hardware is completely non- functional (driver doesn't recognize the device) - **Impact**: HIGH for affected users - their Bluetooth doesn't work at all
The commit includes detailed `/sys/kernel/debug/usb/devices` output showing real hardware, indicating this comes from actual user/vendor testing.
### 6. STABILITY INDICATORS
- Authored by MediaTek (chip vendor) with direct hardware knowledge - Reviewed by community member - Signed off by the Bluetooth subsystem maintainer - Follows established pattern of many similar MT7922 device ID entries visible in the diff context
### 7. DEPENDENCY CHECK
- **No dependencies**: This is a self-contained table entry addition - **Existing support**: The BTUSB_MEDIATEK and BTUSB_WIDEBAND_SPEECH flags and MT7922 support code exist in all recent stable trees - **Clean application**: Should apply cleanly to any stable tree that has MT7922 support
### CONCLUSION
This commit is a textbook example of what SHOULD be backported to stable:
1. **Falls under Device ID Exception**: Explicitly allowed category for stable 2. **Fixes Real User Problem**: Enables Bluetooth hardware that would otherwise be completely non-functional 3. **Minimal Risk**: 2-line table entry addition, cannot break anything else 4. **No New Features**: Just enables existing driver for new hardware variant 5. **Well-Reviewed**: Proper sign-offs from vendor and maintainer 6. **Clear Benefit**: Users with this hardware get working Bluetooth
The lack of explicit stable tag is typical for device ID additions - stable maintainers routinely accept these. The benefit (enabling hardware) far outweighs the near-zero risk.
**YES**
drivers/bluetooth/btusb.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c index 595afeff4afb5..9b199da1c0d67 100644 --- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -687,6 +687,8 @@ static const struct usb_device_id quirks_table[] = { BTUSB_WIDEBAND_SPEECH }, { USB_DEVICE(0x0489, 0xe153), .driver_info = BTUSB_MEDIATEK | BTUSB_WIDEBAND_SPEECH }, + { USB_DEVICE(0x0489, 0xe170), .driver_info = BTUSB_MEDIATEK | + BTUSB_WIDEBAND_SPEECH }, { USB_DEVICE(0x04ca, 0x3804), .driver_info = BTUSB_MEDIATEK | BTUSB_WIDEBAND_SPEECH }, { USB_DEVICE(0x04ca, 0x38e4), .driver_info = BTUSB_MEDIATEK |