[PATCH AUTOSEL 6.18-6.12] Bluetooth: btusb: MT7922: Add VID/PID 0489/e170

[PATCH AUTOSEL 6.18-6.12] Bluetooth: btusb: MT7922: Add VID/PID 0489/e170

[Sasha Levin]

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:



 drivers/bluetooth/btusb.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index c70e79e69be8d..36f18f2657ab8 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -685,6 +685,8 @@ 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 |
-- 
2.51.0

[PATCH AUTOSEL 6.18-5.10] Bluetooth: btusb: Add new VID/PID 13d3/3533 for RTL8821CE

[Sasha Levin]

From: Gongwei Li <ligongwei@kylinos.cn>

[ Upstream commit 525459da4bd62a81142fea3f3d52188ceb4d8907 ]

Add VID 13d3 & PID 3533 for Realtek RTL8821CE USB Bluetooth chip.

The information in /sys/kernel/debug/usb/devices about the Bluetooth
device is listed as the below.

T:  Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#=  2 Spd=12   MxCh= 0
D:  Ver= 1.10 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=13d3 ProdID=3533 Rev= 1.10
S:  Manufacturer=Realtek
S:  Product=Bluetooth Radio
S:  SerialNumber=00e04c000001
C:* #Ifs= 2 Cfg#= 1 Atr=e0 MxPwr=500mA
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=1ms
E:  Ad=02(O) Atr=02(Bulk) MxPS=  64 Ivl=0ms
E:  Ad=82(I) Atr=02(Bulk) MxPS=  64 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E:  Ad=03(O) Atr=01(Isoc) MxPS=   0 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=   9 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  17 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  25 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  33 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  49 Ivl=1ms
E:  Ad=83(I) Atr=01(Isoc) MxPS=  49 Ivl=1ms

Signed-off-by: Gongwei Li <ligongwei@kylinos.cn>
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:

## Commit Analysis: Bluetooth: btusb: Add new VID/PID 13d3/3533 for
RTL8821CE

### 1. COMMIT MESSAGE ANALYSIS

**Subject:** Adding a new USB Vendor ID (0x13d3) and Product ID (0x3533)
for a Realtek RTL8821CE Bluetooth chip.

**Tags present:**
- No "Fixes:" tag
- No "Cc: stable@vger.kernel.org" tag
- Signed-off-by from contributor and Bluetooth maintainer (Luiz Augusto
  von Dentz)

**Key content:** The commit includes detailed USB device information
showing this is a real, tested device from the
`/sys/kernel/debug/usb/devices` output.

### 2. CODE CHANGE ANALYSIS

The diff shows a simple 2-line addition:

```c
/* Realtek 8821CE Bluetooth devices */
{ USB_DEVICE(0x13d3, 0x3529), .driver_info = BTUSB_REALTEK |
                                             BTUSB_WIDEBAND_SPEECH },
+{ USB_DEVICE(0x13d3, 0x3533), .driver_info = BTUSB_REALTEK |
+                                            BTUSB_WIDEBAND_SPEECH },
```

- Adds USB device entry with VID 0x13d3, PID 0x3533
- Uses **identical** flags as the existing RTL8821CE entry (0x13d3,
  0x3529)
- Placed directly under the "Realtek 8821CE Bluetooth devices" comment
- Follows established table pattern exactly

### 3. CLASSIFICATION

This is a **NEW DEVICE ID** addition - one of the explicit exceptions
for stable backports:

> "Adding PCI IDs, USB IDs, ACPI IDs, etc. to existing drivers. These
are trivial one-line additions that enable hardware support."

The btusb driver already fully supports RTL8821CE devices; this just
adds a new variant's USB ID to the match table.

### 4. SCOPE AND RISK ASSESSMENT

| Metric | Assessment |
|--------|------------|
| Lines changed | 2 lines added |
| Files touched | 1 file (drivers/bluetooth/btusb.c) |
| Complexity | Trivial - table entry only |
| Risk | **Extremely low** - purely additive |

**Risk analysis:**
- Cannot break existing functionality (new table entry only)
- Uses same driver_info flags as sibling device
- Only affects users with this specific USB hardware
- If somehow wrong, worst case is Bluetooth doesn't work for this device
  (no worse than before)

### 5. USER IMPACT

- **Affected users:** Those with laptops/devices containing this
  Bluetooth chip variant
- **Current behavior:** Bluetooth device not recognized by btusb driver
- **Fixed behavior:** Bluetooth works normally
- **Severity:** Hardware enablement - critical for affected users
- **Evidence of real use:** Detailed USB device tree dump proves this is
  real, tested hardware

### 6. STABILITY INDICATORS

- Proper maintainer sign-off (Luiz Augusto von Dentz, Intel Bluetooth
  maintainer)
- Matches exact pattern of existing entries
- Same flags as the sibling 8821CE entry (0x13d3/0x3529)

### 7. DEPENDENCY CHECK

- **Dependencies:** None - completely standalone table entry
- **Prerequisite code:** RTL8821CE support (BTUSB_REALTEK,
  BTUSB_WIDEBAND_SPEECH) already exists in stable trees
- **Applies cleanly:** The quirks_table structure has been stable for a
  long time

## Summary

This commit is a textbook example of the "NEW DEVICE ID" exception for
stable backports:

**Reasons to backport:**
1. Trivial 2-line USB ID table addition
2. Zero risk of regression to existing functionality
3. Enables Bluetooth for users with this specific hardware variant
4. Follows established, well-tested patterns exactly
5. No dependencies on other commits
6. Driver already fully supports this chip family

**Minor consideration:**
- No explicit "Cc: stable" tag, but device ID additions are routinely
  backported without it

The fix is small, surgical, and follows an explicit exception in stable
kernel rules for device ID additions.

**YES**

 drivers/bluetooth/btusb.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 9a923918bf741..b92bfd131567e 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -504,6 +504,8 @@ static const struct usb_device_id quirks_table[] = {
 	/* Realtek 8821CE Bluetooth devices */
 	{ USB_DEVICE(0x13d3, 0x3529), .driver_info = BTUSB_REALTEK |
 						     BTUSB_WIDEBAND_SPEECH },
+	{ USB_DEVICE(0x13d3, 0x3533), .driver_info = BTUSB_REALTEK |
+						     BTUSB_WIDEBAND_SPEECH },
 
 	/* Realtek 8822CE Bluetooth devices */
 	{ USB_DEVICE(0x0bda, 0xb00c), .driver_info = BTUSB_REALTEK |
-- 
2.51.0

[PATCH AUTOSEL 6.18-6.12] Bluetooth: btusb: Add new VID/PID 0x0489/0xE12F for RTL8852BE-VT

[Sasha Levin]

From: Max Chou <max.chou@realtek.com>

[ Upstream commit 32caa197b9b603e20f49fd3a0dffecd0cd620499 ]

Add the support ID(0x0489, 0xE12F) to usb_device_id table for
Realtek RTL8852BE-VT.

The device info from /sys/kernel/debug/usb/devices as below.

T:  Bus=04 Lev=02 Prnt=02 Port=05 Cnt=01 Dev#= 86 Spd=12   MxCh= 0
D:  Ver= 1.00 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=0489 ProdID=e12f Rev= 0.00
S:  Manufacturer=Realtek
S:  Product=Bluetooth Radio
S:  SerialNumber=00e04c000001
C:* #Ifs= 2 Cfg#= 1 Atr=e0 MxPwr=500mA
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=1ms
E:  Ad=02(O) Atr=02(Bulk) MxPS=  64 Ivl=0ms
E:  Ad=82(I) Atr=02(Bulk) MxPS=  64 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E:  Ad=03(O) Atr=01(Isoc) MxPS=   0 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=   9 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  17 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  25 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  33 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  49 Ivl=1ms
E:  Ad=83(I) Atr=01(Isoc) MxPS=  49 Ivl=1ms

Signed-off-by: Max Chou <max.chou@realtek.com>
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:

## Commit Analysis: Bluetooth: btusb: Add new VID/PID 0x0489/0xE12F for
RTL8852BE-VT

### 1. COMMIT MESSAGE ANALYSIS

- **Subject**: Adding a new USB Vendor/Product ID for a Realtek
  Bluetooth chip variant
- **No "Cc: stable@vger.kernel.org"** tag present
- **No "Fixes:"** tag present
- Commit message includes detailed device info from
  `/sys/kernel/debug/usb/devices`, confirming this is real hardware
  that's been tested
- Signed off by Realtek engineer (the hardware vendor) and Bluetooth
  maintainer

### 2. CODE CHANGE ANALYSIS

The diff is extremely simple:
```c
+       { USB_DEVICE(0x0489, 0xe12f), .driver_info = BTUSB_REALTEK |
+
BTUSB_WIDEBAND_SPEECH },
```

- **2 lines added** to the `quirks_table[]` static array
- Uses identical `driver_info` flags as the existing RTL8852BE-VT entry
  (`0x0bda, 0x8520`)
- Placed in the appropriate "Realtek 8852BT/8852BE-VT Bluetooth devices"
  section
- No code logic changes whatsoever - just adding an entry to a USB
  device ID table

### 3. CLASSIFICATION

This falls squarely under the **NEW DEVICE IDs** exception, which is
explicitly allowed in stable:

> "Adding PCI IDs, USB IDs, ACPI IDs, etc. to existing drivers - These
are trivial one-line additions that enable hardware support"

This is **not** a new feature. The btusb driver already fully supports
RTL8852BE-VT devices. This simply registers another VID/PID combination
for the same chipset.

### 4. SCOPE AND RISK ASSESSMENT

| Factor | Assessment |
|--------|------------|
| Lines changed | 2 (minimal) |
| Files touched | 1 (`drivers/bluetooth/btusb.c`) |
| Complexity | Trivial - static table entry |
| Risk | **Extremely low** |

- Change only affects devices matching VID 0x0489 / PID 0xe12f
- Cannot regress any existing functionality
- No behavioral changes to the driver code itself

### 5. USER IMPACT

- **Without this patch**: Users with this Bluetooth adapter have non-
  functional hardware
- **With this patch**: The adapter is recognized and works with existing
  Realtek support
- **Severity for affected users**: High - complete loss of Bluetooth
  functionality
- This is a real Realtek product (vendor confirmed via signoff)

### 6. STABILITY INDICATORS

- Submitted by Realtek engineer (Max Chou) - hardware vendor
- Merged by Bluetooth maintainer (Luiz von Dentz)
- Device info in commit message demonstrates the device exists and was
  tested

### 7. DEPENDENCY CHECK

- No dependencies on other commits
- The btusb driver with Realtek support (`BTUSB_REALTEK`) exists in all
  stable trees
- `BTUSB_WIDEBAND_SPEECH` flag is also well-established

---

## Summary

This is a textbook example of a commit that should be backported to
stable:

**Benefits**:
- Enables real hardware for real users
- Zero risk of regression (only affects specific VID/PID)
- Trivial 2-line data table addition
- Obviously correct - follows exact same pattern as dozens of other
  entries
- Hardware vendor submitted the patch

**Concerns**:
- No explicit stable tags (common for device ID additions; maintainers
  often omit these for routine changes)

The absence of `Cc: stable` is not concerning for device ID additions -
they're so routine that many maintainers don't bother tagging them, yet
stable maintainers regularly pick them up. This enables users with this
Bluetooth adapter to have working hardware on stable kernels without
requiring a full kernel upgrade.

**YES**

 drivers/bluetooth/btusb.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index cc03c8c38b16f..a5b73e0d271f3 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -585,6 +585,8 @@ static const struct usb_device_id quirks_table[] = {
 	/* Realtek 8852BT/8852BE-VT Bluetooth devices */
 	{ USB_DEVICE(0x0bda, 0x8520), .driver_info = BTUSB_REALTEK |
 						     BTUSB_WIDEBAND_SPEECH },
+	{ USB_DEVICE(0x0489, 0xe12f), .driver_info = BTUSB_REALTEK |
+						     BTUSB_WIDEBAND_SPEECH },
 
 	/* Realtek 8922AE Bluetooth devices */
 	{ USB_DEVICE(0x0bda, 0x8922), .driver_info = BTUSB_REALTEK |
-- 
2.51.0

[PATCH AUTOSEL 6.18-6.12] Bluetooth: btusb: MT7920: Add VID/PID 0489/e135

[Sasha Levin]

From: Chris Lu <chris.lu@mediatek.com>

[ Upstream commit c126f98c011f5796ba118ef2093122d02809d30d ]

Add VID 0489 & PID e135 for MediaTek MT7920 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=e135 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=  64 Ivl=125us
E:  Ad=0a(O) Atr=03(Int.) MxPS=  64 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:

## Commit Analysis: Bluetooth btusb MT7920 VID/PID Addition

### 1. COMMIT MESSAGE ANALYSIS

**Subject:** Adding a new USB VID/PID (0489/e135) for MediaTek MT7920
Bluetooth chip

**Key observations:**
- No `Cc: stable@vger.kernel.org` tag (not unusual for device ID
  additions)
- No `Fixes:` tag (not applicable - this enables new hardware, doesn't
  fix a bug)
- Author is from MediaTek (hardware vendor)
- Has `Reviewed-by` from Paul Menzel
- Signed off by Bluetooth maintainer Luiz Augusto von Dentz

### 2. CODE CHANGE ANALYSIS

The change is minimal:
```c
+       { USB_DEVICE(0x0489, 0xe135), .driver_info = BTUSB_MEDIATEK |
+
BTUSB_WIDEBAND_SPEECH },
```

This adds a single USB device ID entry to the `quirks_table[]` in
`drivers/bluetooth/btusb.c`. The entry:
- Uses VID 0x0489, PID 0xe135
- Uses identical flags to the adjacent MT7920 entry (0x0489, 0xe134)
- Follows the exact pattern of all other MediaTek device entries

### 3. CLASSIFICATION

This falls squarely into the **"NEW DEVICE IDs"** exception category for
stable backports. Per the stable kernel rules:

> Adding PCI IDs, USB IDs, ACPI IDs, etc. to existing drivers - These
are trivial one-line additions that enable hardware support

The btusb driver already fully supports MediaTek MT7920 devices; this
just adds recognition for a new variant.

### 4. SCOPE AND RISK ASSESSMENT

| Factor | Assessment |
|--------|------------|
| Lines changed | 2 (effectively 1 entry) |
| Files touched | 1 |
| Complexity | Trivial |
| Risk | Essentially zero |

**Risk justification:** This only affects devices with exactly
VID=0x0489 and PID=0xe135. It cannot cause regressions for any other
hardware. The change is purely additive with no modification to existing
functionality.

### 5. USER IMPACT

**Without this patch:** Users with MT7920 Bluetooth USB adapters using
this VID/PID combination have no Bluetooth functionality - the kernel
doesn't recognize their device.

**With this patch:** Bluetooth works normally using the mature, existing
MediaTek btusb support.

The USB device information in the commit message confirms this is real
hardware that users possess.

### 6. STABILITY INDICATORS

- ✅ Reviewed by Paul Menzel
- ✅ Signed off by Bluetooth subsystem maintainer
- ✅ Author from hardware vendor (MediaTek)
- ✅ Identical pattern to many existing entries
- ✅ Same flags used as sister device (e134)

### 7. DEPENDENCY CHECK

- **No dependencies** on other commits
- Uses existing macros (`USB_DEVICE`) and flags (`BTUSB_MEDIATEK`,
  `BTUSB_WIDEBAND_SPEECH`)
- The btusb driver with MediaTek MT7920 support exists in stable kernels

### CONCLUSION

This is a textbook stable-appropriate device ID addition:

1. **Trivial 2-line change** - lowest possible complexity
2. **Zero regression risk** - only affects one specific hardware variant
3. **Real user impact** - enables Bluetooth for users with this hardware
4. **Well-reviewed** - proper sign-offs from maintainer and vendor
5. **No new code** - leverages existing, mature MediaTek btusb support
6. **No dependencies** - applies cleanly to any kernel with MT7920
   support

Device ID additions like this are routinely backported to stable trees
because they provide clear value (enabling hardware) with essentially no
risk. The pattern is identical to dozens of similar entries in the same
file.

**YES**

 drivers/bluetooth/btusb.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index fa683bb7f0b49..595afeff4afb5 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -621,6 +621,8 @@ static const struct usb_device_id quirks_table[] = {
 	/* Additional MediaTek MT7920 Bluetooth devices */
 	{ USB_DEVICE(0x0489, 0xe134), .driver_info = BTUSB_MEDIATEK |
 						     BTUSB_WIDEBAND_SPEECH },
+	{ USB_DEVICE(0x0489, 0xe135), .driver_info = BTUSB_MEDIATEK |
+						     BTUSB_WIDEBAND_SPEECH },
 	{ USB_DEVICE(0x13d3, 0x3620), .driver_info = BTUSB_MEDIATEK |
 						     BTUSB_WIDEBAND_SPEECH },
 	{ USB_DEVICE(0x13d3, 0x3621), .driver_info = BTUSB_MEDIATEK |
-- 
2.51.0

[PATCH AUTOSEL 6.18-6.12] Bluetooth: btusb: MT7922: Add VID/PID 0489/e170

[Sasha Levin]

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 |
-- 
2.51.0

[PATCH AUTOSEL 6.18-6.17] Bluetooth: btusb: add new custom firmwares

[Sasha Levin]

From: Shuai Zhang <quic_shuaz@quicinc.com>

[ Upstream commit a8b38d19857d42a1f2e90c9d9b0f74de2500acd7 ]

The new platform uses the QCA2066 chip along with a new board ID, which
requires a dedicated firmware file to ensure proper initialization.
Without this entry, the driver cannot locate and load the correct
firmware, resulting in Bluetooth bring-up failure.

This patch adds a new entry to the firmware table for QCA2066 so that
the driver can correctly identify the board ID and load the appropriate
firmware from 'qca/QCA2066/' in the linux-firmware repository.

Signed-off-by: Shuai Zhang <quic_shuaz@quicinc.com>
Acked-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
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:

### Backport Considerations

The prerequisite QCA2066 support was introduced in v6.17 (commit
a3f9f6dd047af). This means:
- Only 6.17.y stable tree would benefit from this backport
- Earlier LTS trees (6.12.y, 6.6.y, 6.1.y, 5.15.y) don't have the
  required infrastructure

## Summary

| Criterion | Assessment |
|-----------|------------|
| Bug fix? | ✅ Fixes Bluetooth bring-up failure |
| Obviously correct? | ✅ Single table entry matching existing pattern |
| Small and contained? | ✅ 1 line, 1 file |
| Tested? | ✅ Acked by Qualcomm developer, signed by maintainer |
| Risk? | ✅ Extremely low - isolated hardware variant |
| User impact? | ✅ Complete Bluetooth loss without fix |
| Exception category? | ✅ NEW DEVICE IDs (board_id addition) |

**Conclusion:**

This is a textbook example of the "NEW DEVICE IDs" stable exception. It
adds a single board_id entry to an existing firmware lookup table to
enable Bluetooth on a new hardware variant. The change:
- Fixes a real user problem (non-working Bluetooth)
- Is trivially small and obviously correct
- Has essentially zero regression risk
- Only affects new hardware that wouldn't work otherwise

While it lacks explicit stable tags, this type of hardware enablement is
routinely accepted for stable backporting because it matches the pattern
of USB/PCI ID additions. The only limitation is that backporting only
applies to 6.17.y since the QCA2066 infrastructure doesn't exist in
earlier kernels.

**YES**

 drivers/bluetooth/btusb.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index a5b73e0d271f3..9a923918bf741 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -3269,6 +3269,7 @@ static const struct qca_device_info qca_devices_table[] = {
 
 static const struct qca_custom_firmware qca_custom_btfws[] = {
 	{ 0x00130201, 0x030A, "QCA2066" },
+	{ 0x00130201, 0x030B, "QCA2066" },
 	{ },
 };
 
-- 
2.51.0

[PATCH AUTOSEL 6.18-6.6] Bluetooth: btusb: Add new VID/PID 2b89/6275 for RTL8761BUV

[Sasha Levin]

From: Chingbin Li <liqb365@163.com>

[ Upstream commit 8dbbb5423c0802ec21266765de80fd491868fab1 ]

Add VID 2b89 & PID 6275 for Realtek RTL8761BUV USB Bluetooth chip.

The information in /sys/kernel/debug/usb/devices about the Bluetooth
device is listed as the below.

T:  Bus=01 Lev=01 Prnt=01 Port=02 Cnt=01 Dev#=  6 Spd=12   MxCh= 0
D:  Ver= 1.10 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=2b89 ProdID=6275 Rev= 2.00
S:  Manufacturer=Realtek
S:  Product=Bluetooth Radio
S:  SerialNumber=00E04C239987
C:* #Ifs= 2 Cfg#= 1 Atr=e0 MxPwr=500mA
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=1ms
E:  Ad=02(O) Atr=02(Bulk) MxPS=  64 Ivl=0ms
E:  Ad=82(I) Atr=02(Bulk) MxPS=  64 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E:  Ad=03(O) Atr=01(Isoc) MxPS=   0 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=   9 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  17 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  25 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  33 Ivl=1ms
E:  Ad=83(I) 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=03(O) Atr=01(Isoc) MxPS=  49 Ivl=1ms
E:  Ad=83(I) Atr=01(Isoc) MxPS=  49 Ivl=1ms

Signed-off-by: Chingbin Li <liqb365@163.com>
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:

## Commit Analysis: Bluetooth: btusb: Add new VID/PID 2b89/6275 for
RTL8761BUV

### 1. COMMIT MESSAGE ANALYSIS

- **Subject:** Adding a USB VID (0x2b89) / PID (0x6275) for a Realtek
  RTL8761BUV Bluetooth chip
- **No "Fixes:" tag** - This is not fixing a code bug
- **No "Cc: stable@vger.kernel.org"** - Not explicitly tagged for stable
- **Evidence of real hardware:** The commit includes detailed USB device
  information from `/sys/kernel/debug/usb/devices`, showing the
  contributor has physical access to the device

### 2. CODE CHANGE ANALYSIS

The change is minimal - just 2 lines added to
`drivers/bluetooth/btusb.c`:

```c
{ USB_DEVICE(0x2b89, 0x6275), .driver_info = BTUSB_REALTEK |
                                             BTUSB_WIDEBAND_SPEECH },
```

This entry:
- Is added to the `quirks_table[]` array in the "Additional Realtek
  8761BUV Bluetooth devices" section
- Uses the exact same pattern and flags as other RTL8761BUV entries
- The same vendor ID (0x2b89) already exists with a different product ID
  (0x8761)

### 3. CLASSIFICATION

This is a **NEW DEVICE ID** addition - one of the explicitly allowed
exceptions for stable trees:
- Adds a USB ID to an existing, mature driver (btusb)
- The btusb driver already fully supports RTL8761BUV chips
- Only the device ID is new, not any driver functionality

### 4. SCOPE AND RISK ASSESSMENT

| Factor | Assessment |
|--------|------------|
| Lines changed | 2 |
| Files touched | 1 |
| Complexity | Trivial - mechanical ID table addition |
| Risk of regression | Essentially zero |
| Pattern precedent | Exact same pattern used by dozens of other entries
|

The risk is **extremely low** because:
- The new entry cannot affect any existing devices
- It only matches the specific VID/PID combination
- All the handling code (BTUSB_REALTEK, BTUSB_WIDEBAND_SPEECH) is
  already tested with similar hardware

### 5. USER IMPACT

- **Affected users:** Anyone with a Bluetooth USB adapter using VID
  0x2b89 and PID 0x6275
- **Without the patch:** The device is not recognized, Bluetooth does
  not work at all
- **With the patch:** Full Bluetooth functionality via the mature btusb
  driver

This is a complete enablement fix for affected hardware.

### 6. STABILITY INDICATORS

- Signed-off-by from the Bluetooth subsystem maintainer (Luiz Augusto
  von Dentz)
- Follows established patterns exactly
- USB device info in commit shows real-world testing on actual hardware

### 7. DEPENDENCY CHECK

- **No dependencies** on other commits
- The required flags (BTUSB_REALTEK, BTUSB_WIDEBAND_SPEECH) have existed
  for years
- Will apply cleanly to all stable trees with btusb support

---

## Summary

This commit is a textbook example of a stable-appropriate device ID
addition:

**Pros:**
- Trivial 2-line change adding a USB VID/PID
- Zero risk of regression - only affects the specific new device
- Enables real hardware for users who otherwise have no Bluetooth
- Follows exact pattern used by many other stable-backported device ID
  additions
- Already merged by subsystem maintainer

**Cons:**
- No explicit stable tag (but not required for device ID additions)
- No Fixes: tag (appropriate - this isn't fixing broken code)

**Risk vs Benefit:** Near-zero risk with clear benefit for hardware
owners.

Per the stable kernel rules, device ID additions to existing drivers are
explicitly appropriate for backporting. They are small, obviously
correct, fix a real user problem (hardware not working), and cannot
introduce regressions.

**YES**

 drivers/bluetooth/btusb.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 9b199da1c0d67..cc03c8c38b16f 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -785,6 +785,8 @@ static const struct usb_device_id quirks_table[] = {
 						     BTUSB_WIDEBAND_SPEECH },
 	{ USB_DEVICE(0x2b89, 0x8761), .driver_info = BTUSB_REALTEK |
 						     BTUSB_WIDEBAND_SPEECH },
+	{ USB_DEVICE(0x2b89, 0x6275), .driver_info = BTUSB_REALTEK |
+						     BTUSB_WIDEBAND_SPEECH },
 
 	/* Additional Realtek 8821AE Bluetooth devices */
 	{ USB_DEVICE(0x0b05, 0x17dc), .driver_info = BTUSB_REALTEK },
-- 
2.51.0