[PATCH AUTOSEL 6.19-5.15] HID: elecom: Add support for ELECOM HUGE Plus M-HT1MRBK

[PATCH AUTOSEL 6.19-5.15] HID: elecom: Add support for ELECOM HUGE Plus M-HT1MRBK

[Sasha Levin]

From: David Phillips <david@profile.sh>

[ Upstream commit b8e5fdf0bd022cd5493a5987ef66f5a24f8352d8 ]

New model in the ELECOM HUGE trackball line that has 8 buttons but the
report descriptor specifies only 5. The HUGE Plus supports connecting via
Bluetooth, 2.4GHz wireless USB dongle, and directly via a USB-C cable.
Each connection type reports a different device id, 01AA for cable,
01AB for USB dongle, and 01AC for Bluetooth.

This patch adds these device IDs and applies the fixups similar to the
other ELECOM devices to get all 8 buttons working for all 3 connection
types.

For reference, the usbhid-dump output:
001:013:001:DESCRIPTOR         1769085639.598405
 05 01 09 02 A1 01 85 01 09 01 A1 00 05 09 19 01
 29 05 15 00 25 01 75 01 95 05 81 02 75 03 95 01
 81 01 05 01 09 30 09 31 16 01 80 26 FF 7F 75 10
 95 02 81 06 09 38 15 81 25 7F 75 08 95 01 81 06
 05 0C 0A 38 02 15 81 25 7F 75 08 95 01 81 06 C0
 C0 05 0C 09 01 A1 01 85 02 15 01 26 8C 02 19 01
 2A 8C 02 75 10 95 01 81 00 C0 05 01 09 80 A1 01
 85 03 09 82 09 81 09 83 15 00 25 01 19 01 29 03
 75 01 95 03 81 02 95 05 81 01 C0 06 01 FF 09 00
 A1 01 85 08 09 00 15 00 26 FF 00 75 08 95 07 81
 02 C0 06 02 FF 09 02 A1 01 85 06 09 02 15 00 26
 FF 00 75 08 95 07 B1 02 C0

Signed-off-by: David Phillips <david@profile.sh>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:

## Analysis

### Commit Message Analysis

This commit adds support for the ELECOM HUGE Plus trackball (M-HT1MRBK)
across three connection types (USB-C cable, 2.4GHz USB dongle,
Bluetooth). The device has 8 buttons but the HID report descriptor only
reports 5, so the driver applies a report descriptor fixup to expose all
8 buttons — the same pattern used for other ELECOM devices already
supported by this driver.

### Code Change Analysis

The changes span 4 files:

1. **`drivers/hid/hid-ids.h`**: Adds 3 new device ID defines (0x01aa,
   0x01ab, 0x01ac) for the three connection types.

2. **`drivers/hid/hid-elecom.c`**:
   - Adds a new case block in `elecom_report_fixup()` for the three new
     device IDs, calling `mouse_button_fixup()` with appropriate offsets
     (24, 28, 22, 16, 8). Note the offsets differ slightly from the
     existing HUGE (M-HT1DRBK) which uses (22, 30, 24, 16, 8) — this is
     because the HUGE Plus has a different report descriptor format as
     shown in the commit message.
   - Adds the three device IDs to `elecom_devices[]` table (USB for 01AA
     and 01AB, Bluetooth for 01AC).

3. **`drivers/hid/hid-quirks.c`**: Adds the three device IDs to
   `hid_have_special_driver[]` so the HID core knows to route these
   devices to the elecom driver.

4. **`drivers/hid/Kconfig`**: Updates help text to mention the new
   device.

### Classification

This is a **new device ID addition with report descriptor fixup** — one
of the explicitly allowed exception categories for stable backports. The
ELECOM HID driver already exists in stable trees, and this commit adds
IDs for a new variant of an existing product line (HUGE Plus vs HUGE),
applying the same `mouse_button_fixup()` mechanism already used by other
ELECOM devices.

### Scope and Risk Assessment

- **Lines changed**: Small — ~30 lines of meaningful additions across 4
  files.
- **Risk**: Very low. The changes are purely additive (new device IDs +
  new case in switch statement). They cannot affect any existing device
  since they only trigger for the new device IDs. The
  `mouse_button_fixup()` function is already well-tested with other
  ELECOM devices.
- **Pattern**: Follows the exact same pattern as previous ELECOM device
  additions (e.g., the HUGE M-HT1DRBK, DEFT M-DT2DRBK, etc.).

### User Impact

Without this patch, users of the ELECOM HUGE Plus trackball can only use
5 of 8 buttons. This is a real hardware functionality issue — the
device's report descriptor is broken (reports 5 buttons when 8 exist),
and the driver fixup is needed to make all buttons work. This affects
real users who purchased this trackball.

### Stability and Dependencies

- No dependencies on other commits.
- The `mouse_button_fixup()` function and the entire ELECOM driver
  infrastructure exist in stable trees already.
- The patch is self-contained and applies cleanly.
- The different report descriptor offsets (24, 28, 22, 16 vs 22, 30, 24,
  16 for older HUGE) are correctly derived from the actual descriptor
  dump provided in the commit message.

### Conclusion

This is a textbook device ID addition to an existing driver with a
hardware quirk/fixup. It follows the same pattern as all other ELECOM
devices in the driver, is small and self-contained, fixes a real
hardware issue (only 5 of 8 buttons work), and carries essentially zero
risk of regression to existing devices. This falls squarely into the
"new device IDs / hardware quirks" exception category that is explicitly
allowed in stable.

**YES**

 drivers/hid/Kconfig      |  1 +
 drivers/hid/hid-elecom.c | 16 ++++++++++++++++
 drivers/hid/hid-ids.h    |  3 +++
 drivers/hid/hid-quirks.c |  3 +++
 4 files changed, 23 insertions(+)

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 920a64b66b25b..6ff4a3ad34cbf 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -369,6 +369,7 @@ config HID_ELECOM
 	  - EX-G Trackballs (M-XT3DRBK, M-XT3URBK)
 	  - DEFT Trackballs (M-DT1DRBK, M-DT1URBK, M-DT2DRBK, M-DT2URBK)
 	  - HUGE Trackballs (M-HT1DRBK, M-HT1URBK)
+	  - HUGE Plus Trackball (M-HT1MRBK)
 
 config HID_ELO
 	tristate "ELO USB 4000/4500 touchscreen"
diff --git a/drivers/hid/hid-elecom.c b/drivers/hid/hid-elecom.c
index 2003d2dcda7cc..37d88ce57f671 100644
--- a/drivers/hid/hid-elecom.c
+++ b/drivers/hid/hid-elecom.c
@@ -5,6 +5,7 @@
  *  - EX-G Trackballs (M-XT3DRBK, M-XT3URBK, M-XT4DRBK)
  *  - DEFT Trackballs (M-DT1DRBK, M-DT1URBK, M-DT2DRBK, M-DT2URBK)
  *  - HUGE Trackballs (M-HT1DRBK, M-HT1URBK)
+ *  - HUGE Plus Trackball (M-HT1MRBK)
  *
  *  Copyright (c) 2010 Richard Nauber <Richard.Nauber@gmail.com>
  *  Copyright (c) 2016 Yuxuan Shui <yshuiv7@gmail.com>
@@ -123,12 +124,25 @@ static const __u8 *elecom_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 		 */
 		mouse_button_fixup(hdev, rdesc, *rsize, 22, 30, 24, 16, 8);
 		break;
+	case USB_DEVICE_ID_ELECOM_M_HT1MRBK:
+	case USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AB:
+	case USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AC:
+		/*
+		 * Report descriptor format:
+		 * 24: button bit count
+		 * 28: padding bit count
+		 * 22: button report size
+		 * 16: button usage maximum
+		 */
+		mouse_button_fixup(hdev, rdesc, *rsize, 24, 28, 22, 16, 8);
+		break;
 	}
 	return rdesc;
 }
 
 static const struct hid_device_id elecom_devices[] = {
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084) },
+	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AC) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XGL20DLBK) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3URBK_00FB) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3URBK_018F) },
@@ -142,6 +156,8 @@ static const struct hid_device_id elecom_devices[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1URBK_019B) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1DRBK_010D) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1DRBK_011C) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1MRBK) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AB) },
 	{ }
 };
 MODULE_DEVICE_TABLE(hid, elecom_devices);
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 6d8b64872cefe..85ab1ac511096 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -466,6 +466,9 @@
 #define USB_DEVICE_ID_ELECOM_M_HT1URBK_019B	0x019b
 #define USB_DEVICE_ID_ELECOM_M_HT1DRBK_010D	0x010d
 #define USB_DEVICE_ID_ELECOM_M_HT1DRBK_011C	0x011c
+#define USB_DEVICE_ID_ELECOM_M_HT1MRBK	0x01aa
+#define USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AB	0x01ab
+#define USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AC	0x01ac
 
 #define USB_VENDOR_ID_DREAM_CHEEKY	0x1d34
 #define USB_DEVICE_ID_DREAM_CHEEKY_WN	0x0004
diff --git a/drivers/hid/hid-quirks.c b/drivers/hid/hid-quirks.c
index 11438039cdb7f..3217e436c052c 100644
--- a/drivers/hid/hid-quirks.c
+++ b/drivers/hid/hid-quirks.c
@@ -420,6 +420,7 @@ static const struct hid_device_id hid_have_special_driver[] = {
 #if IS_ENABLED(CONFIG_HID_ELECOM)
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084) },
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XGL20DLBK) },
+	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AC) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3URBK_00FB) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3URBK_018F) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3DRBK_00FC) },
@@ -432,6 +433,8 @@ static const struct hid_device_id hid_have_special_driver[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1URBK_019B) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1DRBK_010D) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1DRBK_011C) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1MRBK) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AB) },
 #endif
 #if IS_ENABLED(CONFIG_HID_ELO)
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELO, 0x0009) },
-- 
2.51.0

[PATCH AUTOSEL 6.19-5.10] HID: multitouch: add eGalaxTouch EXC3188 support

[Sasha Levin]

From: Thorsten Schmelzer <tschmelzer@topcon.com>

[ Upstream commit 8e4ac86b2ddd36fe501e20ecfcc080e536df1f48 ]

Add support for the for the EXC3188 touchscreen from eGalaxy.

Signed-off-by: Thorsten Schmelzer <tschmelzer@topcon.com>
Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:

## Analysis

### Commit Message Analysis

The commit adds support for the eGalaxTouch EXC3188 touchscreen device
by adding a new USB device ID (0xC000) to the existing HID multitouch
driver. The commit message is straightforward: "Add support for the
EXC3188 touchscreen from eGalaxy."

### Code Change Analysis

The changes are minimal and confined to two files:

1. **`drivers/hid/hid-ids.h`**: Adds a single `#define` for the new
   device ID:
  ```c
  #define USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_C000  0xc000
  ```

2. **`drivers/hid/hid-multitouch.c`**: Adds a 3-line entry to the
   `mt_devices[]` device ID table:
  ```c
  { .driver_data = MT_CLS_EGALAX_SERIAL,
  MT_USB_DEVICE(USB_VENDOR_ID_DWAV,
  USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_C000) },
  ```

The new device uses `MT_CLS_EGALAX_SERIAL`, which is an existing device
class already used by several other eGalax devices (A001, 73F7, 7349).
No new code paths, no new driver logic, no behavioral changes.

### Classification: New Device ID Addition

This falls squarely into the **"New Device IDs"** exception category for
stable backports:
- The driver (`hid-multitouch`) already exists in stable trees
- Only the device ID is new
- It uses an existing device class (`MT_CLS_EGALAX_SERIAL`)
- The pattern is identical to many other eGalax entries already in the
  table

### Risk Assessment

- **Risk: Extremely low** — This is a pure device ID addition to an
  existing table. It cannot affect any existing device. The new entry
  only matches the specific USB vendor/product ID pair (0x0aec/0xc000).
- **Scope: Minimal** — 4 lines added across 2 files (1 define + 3 lines
  in device table)
- **Dependencies: None** — Completely self-contained, no other commits
  needed

### User Impact

Without this patch, users with the eGalaxTouch EXC3188 touchscreen have
a non-functional device. With this patch, the touchscreen works using
the existing, well-tested eGalax serial multitouch driver class. This is
exactly the kind of hardware enablement that stable users need — their
hardware simply doesn't work without it.

### Stability Indicators

- Uses existing driver infrastructure (no new code paths)
- Follows the exact same pattern as ~20 other eGalax device entries
- Signed off by the HID subsystem maintainer (Jiri Kosina)
- Has been reviewed and accepted through the normal HID subsystem
  process

### Conclusion

This is a textbook example of a device ID addition that should be
backported to stable. It enables real hardware for real users, has zero
risk of regression, requires no dependencies, and follows established
patterns in the driver. These types of commits are explicitly called out
in stable kernel rules as appropriate for backporting.

**YES**

 drivers/hid/hid-ids.h        | 1 +
 drivers/hid/hid-multitouch.c | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 5a18cb41e6d79..6d8b64872cefe 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -437,6 +437,7 @@
 #define USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_7349	0x7349
 #define USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_73F7	0x73f7
 #define USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_A001	0xa001
+#define USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_C000	0xc000
 #define USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_C002	0xc002
 
 #define USB_VENDOR_ID_EDIFIER		0x2d99
diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index f21850f7d89e4..7daa8f6d81870 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -2212,6 +2212,9 @@ static const struct hid_device_id mt_devices[] = {
 	{ .driver_data = MT_CLS_EGALAX_SERIAL,
 		MT_USB_DEVICE(USB_VENDOR_ID_DWAV,
 			USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_A001) },
+	{ .driver_data = MT_CLS_EGALAX_SERIAL,
+		MT_USB_DEVICE(USB_VENDOR_ID_DWAV,
+			USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_C000) },
 	{ .driver_data = MT_CLS_EGALAX,
 		MT_USB_DEVICE(USB_VENDOR_ID_DWAV,
 			USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_C002) },
-- 
2.51.0

[PATCH AUTOSEL 6.19-6.12] HID: logitech-hidpp: Add support for Logitech K980

[Sasha Levin]

From: Bastien Nocera <hadess@hadess.net>

[ Upstream commit af4fe07a9d963a72438ade96cf090e84b3399d0c ]

Add support for the solar-charging Logitech K980 keyboard, over
Bluetooth. Bolt traffic doesn't get routed through logitech-dj, so
this code isn't triggered when Bolt is used.

Signed-off-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:

## Analysis of HID: logitech-hidpp: Add support for Logitech K980

### Commit Message Analysis
The commit adds support for the Logitech K980 (Slim Solar+ keyboard)
over Bluetooth by adding its device ID to the `hidpp_devices` table in
the logitech-hidpp HID driver.

### Code Change Analysis
The change is a **two-line addition** of a new `HID_BLUETOOTH_DEVICE`
entry to the existing `hidpp_devices[]` table:
```c
{ /* Slim Solar+ K980 Keyboard over Bluetooth */
  HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_LOGITECH, 0xb391) },
```

This is the textbook definition of a **new device ID addition** to an
existing driver. The driver (`hid-logitech-hidpp`) already exists in all
stable trees, and this just adds a Bluetooth product ID (0xb391) so the
kernel recognizes and properly handles this keyboard.

### Exception Category: New Device ID
This falls squarely into the "NEW DEVICE IDs" exception category for
stable backports:
- The driver already exists in stable trees
- Only a device ID is being added (no new code paths, no new functions)
- It's a trivial two-line addition to an ID table
- It enables an existing, well-tested driver to work with a specific
  piece of hardware

### Risk Assessment
- **Risk: Extremely low.** Adding an entry to a device ID table cannot
  break any existing functionality. The new entry only matches a
  specific Logitech Bluetooth device (vendor 0x046d, product 0xb391). No
  existing device matching is affected.
- **Scope: Minimal.** Two lines added, one file changed.
- **Dependencies: None.** This is completely self-contained.

### User Impact
Without this patch, users of the Logitech K980 keyboard over Bluetooth
won't get the hidpp driver's features (which for a solar keyboard
includes battery/charging status reporting). With this patch, the
keyboard is properly recognized and handled by the specialized Logitech
HID++ driver.

### Stability Considerations
- The commit was reviewed and applied by the HID subsystem maintainer
  (Jiri Kosina)
- The pattern is identical to dozens of other device ID entries in the
  same table
- Zero chance of regression for existing users

### Conclusion
This is a classic device ID addition — one of the most common and safest
types of stable backports. It enables hardware support for a specific
Logitech keyboard with zero risk to existing functionality. It meets all
stable criteria: obviously correct, small, tested, and fixes a real
issue (device not working with the appropriate driver).

**YES**

 drivers/hid/hid-logitech-hidpp.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index e871f1729d4b3..ca96102121b85 100644
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -4666,6 +4666,8 @@ static const struct hid_device_id hidpp_devices[] = {
 	  HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_LOGITECH, 0xb037) },
 	{ /* MX Anywhere 3SB mouse over Bluetooth */
 	  HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_LOGITECH, 0xb038) },
+	{ /* Slim Solar+ K980 Keyboard over Bluetooth */
+	  HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_LOGITECH, 0xb391) },
 	{}
 };
 
-- 
2.51.0

[PATCH AUTOSEL 6.19-6.18] HID: multitouch: add quirks for Lenovo Yoga Book 9i

[Sasha Levin]

From: Brian Howard <blhoward2@gmail.com>

[ Upstream commit 822bc5b3744b0b2c2c9678aa1d80b2cf04fdfabf ]

The Lenovo Yoga Book 9i is a dual-screen laptop, with a single composite
USB device providing both touch and tablet interfaces for both screens.
All inputs report through a single device, differentiated solely by report
numbers. As there is no way for udev to differentiate the inputs based on
USB vendor/product ID or interface numbers, custom naming is required to
match against for downstream configuration. A firmware bug also results
in an erroneous InRange message report being received after the stylus
leaves proximity, blocking later touch events. Add required quirks for
Gen 8 to Gen 10 models, including a new quirk providing for custom input
device naming and dropping erroneous InRange reports.

Signed-off-by: Brian Howard <blhoward2@gmail.com>
Tested-by: Brian Howard <blhoward2@gmail.com>
Tested-by: Kris Fredrick <linux.baguette800@slmail.me>
Reported-by: Andrei Shumailov <gentoo1993@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220386
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:

Here is my complete analysis:

---

## Commit Analysis: HID: multitouch: add quirks for Lenovo Yoga Book 9i

### 1. COMMIT MESSAGE ANALYSIS

The commit message is clear and well-structured. Key signals:
- **"firmware bug"** explicitly mentioned — erroneous InRange reports
  block touch events
- **Closes: bugzilla.kernel.org/show_bug.cgi?id=220386** — tracked
  kernel bug
- **Reported-by: Andrei Shumailov** — user-reported real-world issue
- **Tested-by** from both the author (Brian Howard) and another user
  (Kris Fredrick) — multiple testers
- **Signed-off-by: Jiri Kosina** — accepted by HID subsystem maintainer

The Lenovo Yoga Book 9i is a dual-screen laptop shipping to consumers.
All touch/stylus inputs are multiplexed through a single USB composite
device.

### 2. CODE CHANGE ANALYSIS

The commit makes changes in **two files** with **73 lines added**:

**a) `drivers/hid/hid-ids.h` — 1 line:**
Adds `USB_DEVICE_ID_LENOVO_YOGABOOK9I 0x6161`. Standard device ID
addition.

**b) `drivers/hid/hid-multitouch.c` — 72 lines across 5 insertion
points:**

1. **New quirk flag** (`MT_QUIRK_YOGABOOK9I BIT(24)`) — follows the
   existing pattern (BIT(23) is `MT_QUIRK_APPLE_TOUCHBAR`).

2. **New device class** (`MT_CLS_YOGABOOK9I 0x0115`) — standard pattern,
   same as `MT_CLS_APPLE_TOUCHBAR 0x0114`, `MT_CLS_SIS 0x0457`, etc.

3. **Class definition in `mt_classes[]`** (~8 lines) — combines existing
   quirk flags (`MT_QUIRK_ALWAYS_VALID`, `MT_QUIRK_FORCE_MULTI_INPUT`,
   `MT_QUIRK_SEPARATE_APP_REPORT`, `MT_QUIRK_HOVERING`) plus the device-
   specific `MT_QUIRK_YOGABOOK9I`. Sets `export_all_inputs = true`. This
   is the exact same pattern used by many existing classes (e.g.,
   `MT_CLS_WIN_8_FORCE_MULTI_INPUT`).

4. **Firmware bug workaround in `mt_report()`** (~30 lines) — **THE
   CRITICAL FIX**: After the stylus leaves proximity, the device
   firmware erroneously sends an all-zero report with InRange set. This
   report is consumed by the multitouch stack and blocks subsequent
   touch events. The fix detects these bogus reports (all relevant
   digitizer fields — InRange, TipSwitch, BarrelSwitch, BarrelSwitch2,
   ContactID, TiltX, TiltY — are zero) and drops them by returning
   early. Without this fix, **touch input becomes non-functional** after
   stylus use.

5. **Custom naming in `mt_input_configured()`** (~20 lines) — Maps
   report IDs to human-readable names (e.g., report 48→"Touchscreen
   Top", 56→"Touchscreen Bottom", 20→"Stylus Top", 40→"Stylus Bottom",
   80→"Emulated Touchpad"). Since all inputs come through a single USB
   device with no interface differentiation, udev has **no other way**
   to distinguish which input corresponds to which physical screen.
   Without this, the dual-screen touchscreen/stylus configuration is
   effectively impossible.

6. **Device ID table entry** (~6 lines) — Standard `HID_DEVICE()` entry
   mapping `USB_VENDOR_ID_LENOVO` + `USB_DEVICE_ID_LENOVO_YOGABOOK9I` to
   `MT_CLS_YOGABOOK9I`.

### 3. CLASSIFICATION

This is a **hardware quirk/workaround**, which falls squarely under the
"QUIRKS and WORKAROUNDS" stable exception:
- Fixes firmware-induced bug that blocks touch events (bug fix)
- Adds device-specific naming for a multiplexed USB device (hardware
  workaround for udev differentiation)
- Uses the well-established `hid-multitouch` quirk framework
- Pattern is identical to Apple Touch Bar, ASUS, SIS, Razer Blade
  Stealth, Smart Tech, and many other device-specific quirk additions

### 4. SCOPE AND RISK ASSESSMENT

**Scope**: 73 lines added across 2 files. All changes are behind a
**device-specific quirk flag** (`MT_QUIRK_YOGABOOK9I`) that is **only
activated** for USB VID:PID `0x17ef:0x6161` (Lenovo Yoga Book 9i).

**Risk**: **EXTREMELY LOW**. The changes:
- Are only triggered for one specific USB device ID
- Do not modify any common code paths
- Do not change behavior for any other hardware
- Use only existing framework constructs (`mt_classes[]` entries, quirk
  flags, `mt_report()` filtering, `mt_input_configured()` naming)
- Are well-tested by multiple users

**Dependencies**: The commit is self-contained. It uses standard HID
definitions (`HID_DG_INRANGE`, `HID_DG_TIPSWITCH`, etc.) and `hid-
multitouch` structures that exist in all current stable trees (v6.1,
v6.6, v6.12). The `for (int ...)` C11 syntax is valid in all stable
trees (kernel uses `-std=gnu11` since v5.18+). The only backport
adjustment needed is the context around BIT(23)/BIT(24) numbering — in
stable trees without `MT_QUIRK_APPLE_TOUCHBAR` (v6.12 and earlier), the
BIT number would need adjustment from 24 to 23. This is a trivial
context fixup.

### 5. USER IMPACT

**HIGH for affected users**: The Lenovo Yoga Book 9i (Gen 8-10) is a
commercially available dual-screen laptop. Without this fix:
- Touch input **stops working** after stylus use (firmware InRange bug)
- Both screens cannot be independently configured (no input
  differentiation)

The bugzilla (#220386) and multiple Reported-by/Tested-by tags confirm
this affects real users.

### 6. STABILITY INDICATORS

- Tested-by from author (Brian Howard) and second tester (Kris Fredrick)
- Signed-off by HID subsystem maintainer (Jiri Kosina)
- Kernel bugzilla with tracking
- Follows well-established pattern in hid-multitouch with many precedent
  quirk additions

### 7. DEPENDENCY CHECK

No dependencies on other patches. The commit is completely self-
contained. All referenced symbols (`HID_DG_INRANGE`, `HID_DG_TIPSWITCH`,
`mt_find_report_data`, `rdata->application->quirks`, `hi->report->id`,
etc.) exist in all current stable kernel trees. Minor context adjustment
may be needed for older stable trees lacking the Apple Touch Bar quirk.

### Verdict

This commit fixes a real firmware bug that **blocks touch events** on
the Lenovo Yoga Book 9i, making the device partially non-functional. It
also provides necessary input naming for the dual-screen device to be
properly configurable. All changes are device-specific hardware quirks
behind a USB VID:PID-gated quirk flag with zero risk to other devices.
The commit follows the well-established hid-multitouch quirk pattern, is
tested by multiple users, and is accepted by the subsystem maintainer.
This is textbook "hardware quirk for a broken device" — exactly the type
of change stable trees are designed to accept.

**YES**

 drivers/hid/hid-ids.h        |  1 +
 drivers/hid/hid-multitouch.c | 72 ++++++++++++++++++++++++++++++++++++
 2 files changed, 73 insertions(+)

diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 9c2bf584d9f6f..5a18cb41e6d79 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -841,6 +841,7 @@
 #define USB_DEVICE_ID_LENOVO_X1_TAB3	0x60b5
 #define USB_DEVICE_ID_LENOVO_X12_TAB	0x60fe
 #define USB_DEVICE_ID_LENOVO_X12_TAB2	0x61ae
+#define USB_DEVICE_ID_LENOVO_YOGABOOK9I	0x6161
 #define USB_DEVICE_ID_LENOVO_OPTICAL_USB_MOUSE_600E	0x600e
 #define USB_DEVICE_ID_LENOVO_PIXART_USB_MOUSE_608D	0x608d
 #define USB_DEVICE_ID_LENOVO_PIXART_USB_MOUSE_6019	0x6019
diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index b1c3ef1290587..f21850f7d89e4 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -76,6 +76,7 @@ MODULE_LICENSE("GPL");
 #define MT_QUIRK_DISABLE_WAKEUP		BIT(21)
 #define MT_QUIRK_ORIENTATION_INVERT	BIT(22)
 #define MT_QUIRK_APPLE_TOUCHBAR		BIT(23)
+#define MT_QUIRK_YOGABOOK9I		BIT(24)
 
 #define MT_INPUTMODE_TOUCHSCREEN	0x02
 #define MT_INPUTMODE_TOUCHPAD		0x03
@@ -231,6 +232,7 @@ static void mt_post_parse(struct mt_device *td, struct mt_application *app);
 #define MT_CLS_RAZER_BLADE_STEALTH		0x0112
 #define MT_CLS_SMART_TECH			0x0113
 #define MT_CLS_APPLE_TOUCHBAR			0x0114
+#define MT_CLS_YOGABOOK9I			0x0115
 #define MT_CLS_SIS				0x0457
 
 #define MT_DEFAULT_MAXCONTACT	10
@@ -427,6 +429,14 @@ static const struct mt_class mt_classes[] = {
 		.quirks = MT_QUIRK_NOT_SEEN_MEANS_UP |
 			MT_QUIRK_ALWAYS_VALID |
 			MT_QUIRK_CONTACT_CNT_ACCURATE,
+	},
+		{ .name = MT_CLS_YOGABOOK9I,
+		.quirks = MT_QUIRK_ALWAYS_VALID |
+			MT_QUIRK_FORCE_MULTI_INPUT |
+			MT_QUIRK_SEPARATE_APP_REPORT |
+			MT_QUIRK_HOVERING |
+			MT_QUIRK_YOGABOOK9I,
+		.export_all_inputs = true
 	},
 	{ }
 };
@@ -1576,6 +1586,38 @@ static void mt_report(struct hid_device *hid, struct hid_report *report)
 	if (rdata && rdata->is_mt_collection)
 		return mt_touch_report(hid, rdata);
 
+	/* Lenovo Yoga Book 9i requires consuming and dropping certain bogus reports */
+	if (rdata && rdata->application &&
+		(rdata->application->quirks & MT_QUIRK_YOGABOOK9I)) {
+
+		bool all_zero_report = true;
+
+		for (int f = 0; f < report->maxfield && all_zero_report; f++) {
+			struct hid_field *fld = report->field[f];
+
+			for (int i = 0; i < fld->report_count; i++) {
+				unsigned int usage = fld->usage[i].hid;
+
+				if (usage == HID_DG_INRANGE ||
+					usage == HID_DG_TIPSWITCH ||
+					usage == HID_DG_BARRELSWITCH ||
+					usage == HID_DG_BARRELSWITCH2 ||
+					usage == HID_DG_CONTACTID ||
+					usage == HID_DG_TILT_X ||
+					usage == HID_DG_TILT_Y) {
+
+					if (fld->value[i] != 0) {
+						all_zero_report = false;
+						break;
+					}
+				}
+			}
+		}
+
+		if (all_zero_report)
+			return;
+	}
+
 	if (field && field->hidinput && field->hidinput->input)
 		input_sync(field->hidinput->input);
 }
@@ -1772,6 +1814,30 @@ static int mt_input_configured(struct hid_device *hdev, struct hid_input *hi)
 		break;
 	}
 
+	/* Lenovo Yoga Book 9i requires custom naming to allow differentiation in udev */
+	if (hi->report && td->mtclass.quirks & MT_QUIRK_YOGABOOK9I) {
+		switch (hi->report->id) {
+		case 48:
+			suffix = "Touchscreen Top";
+			break;
+		case 56:
+			suffix = "Touchscreen Bottom";
+			break;
+		case 20:
+			suffix = "Stylus Top";
+			break;
+		case 40:
+			suffix = "Stylus Bottom";
+			break;
+		case 80:
+			suffix = "Emulated Touchpad";
+			break;
+		default:
+			suffix = "";
+			break;
+		}
+	}
+
 	if (suffix) {
 		hi->input->name = devm_kasprintf(&hdev->dev, GFP_KERNEL,
 						 "%s %s", hdev->name, suffix);
@@ -2277,6 +2343,12 @@ static const struct hid_device_id mt_devices[] = {
 			   USB_VENDOR_ID_LENOVO,
 			   USB_DEVICE_ID_LENOVO_X12_TAB2) },
 
+	/* Lenovo Yoga Book 9i */
+	{ .driver_data = MT_CLS_YOGABOOK9I,
+		HID_DEVICE(BUS_USB, HID_GROUP_MULTITOUCH_WIN_8,
+			   USB_VENDOR_ID_LENOVO,
+			   USB_DEVICE_ID_LENOVO_YOGABOOK9I) },
+
 	/* Logitech devices */
 	{ .driver_data = MT_CLS_NSMU,
 		HID_DEVICE(BUS_BLUETOOTH, HID_GROUP_MULTITOUCH_WIN_8,
-- 
2.51.0

[PATCH AUTOSEL 6.19-6.1] HID: apple: Add "SONiX KN85 Keyboard" to the list of non-apple keyboards

[Sasha Levin]

From: Joey Bednar <linux@joeybednar.com>

[ Upstream commit 7273acfd0aef106093a8ffa3b4973eb70e5a3799 ]

The SoNiX KN85 keyboard identifies as the "Apple, Inc. Aluminium
Keyboard" and is not recognized as a non-apple keyboard. Adding "SoNiX
KN85 Keyboard" to the list of non-apple keyboards fixes the function
keys.

Signed-off-by: Joey Bednar <linux@joeybednar.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:

This confirms the exact same pattern. The "SONiX KN85 Keyboard"
identifies itself as an Apple keyboard (via vendor/product IDs matching
Apple's Aluminium Keyboard) but has a different HID name string than
"SONiX USB DEVICE", so the existing entry doesn't match it. The
`strncmp` prefix match means "SONiX USB DEVICE" would only match devices
whose name starts with exactly that string — "SONiX KN85 Keyboard"
starts with "SONiX KN" which doesn't match "SONiX USB".

---

## Complete Analysis

### 1. COMMIT MESSAGE ANALYSIS

The commit message is clear and concise:
- **Problem**: The SoNiX KN85 keyboard identifies itself (via USB
  VID:PID) as the "Apple, Inc. Aluminium Keyboard" but is not an Apple
  keyboard.
- **Consequence**: Without the fix, the HID apple driver applies Apple-
  specific function key mapping (`fnmode=1`, fkeyslast), making the
  function keys behave as media keys by default. This is wrong for a
  non-Apple keyboard.
- **Fix**: Adding the keyboard's name string to the
  `non_apple_keyboards[]` list so it gets properly detected and uses
  `fnmode=2` (fkeysfirst) by default.
- The commit was signed off by the HID subsystem maintainer Jiri Kosina,
  confirming it was accepted through the proper review process.

### 2. CODE CHANGE ANALYSIS

The change is a **single line addition** to a static constant array:

```356:367:drivers/hid/hid-apple.c
static const struct apple_non_apple_keyboard non_apple_keyboards[] = {
        { "SONiX USB DEVICE" },
        { "SONiX AK870 PRO" },
        // ... rest of array
};
```

The new entry `{ "SONiX KN85 Keyboard" }` is added at the top. The
matching mechanism (`apple_is_non_apple_keyboard()` at line 369) does a
`strncmp` prefix comparison, so the full name "SONiX KN85 Keyboard"
would need to start with "SONiX KN85 Keyboard" to match (which it does
exactly). The existing "SONiX USB DEVICE" entry does NOT match because
the KN85 keyboard reports its name starting with "SONiX KN85", not
"SONiX USB".

### 3. CLASSIFICATION

This is a **hardware quirk/workaround**. The SoNiX KN85 keyboard is a
non-Apple keyboard that falsely presents Apple USB vendor/product IDs (a
common practice for cheap third-party keyboards), causing it to be
handled by the `hid-apple` driver. The driver then applies Apple-
specific key translation logic to a keyboard that doesn't need or want
it, breaking the function keys for the user.

This falls squarely into the "QUIRKS and WORKAROUNDS" exception category
for stable backporting:
- It's a hardware-specific fix for a real device with broken behavior
- It uses an existing mechanism (the `non_apple_keyboards` array)
- It fixes a real user-facing issue (broken function keys)

### 4. SCOPE AND RISK ASSESSMENT

- **Size**: 1 line added to a data array. Cannot be smaller.
- **Files touched**: 1 (`drivers/hid/hid-apple.c`)
- **Complexity**: Zero — it's a string literal added to an array
- **Risk of regression**: Effectively zero. The string match only
  triggers for devices reporting "SONiX KN85 Keyboard" as their name. No
  other devices are affected. The matching is by HID device name, not
  vendor/product ID, so it's extremely targeted.
- **Dependencies**: None. The `non_apple_keyboards[]` mechanism exists
  in all relevant stable trees (introduced in v6.0-rc1).

### 5. USER IMPACT

- **Who is affected**: Users of the SoNiX KN85 keyboard running Linux.
  These are real-world hardware owners.
- **Severity**: Without this fix, the function keys (F1-F12) on the KN85
  keyboard are mapped to media keys by default (brightness, volume,
  etc.), which is wrong for this keyboard. This makes the keyboard
  effectively unusable for standard function key operations unless the
  user manually overrides `fnmode` via a module parameter.
- **Workaround exists**: Users can set `fnmode=2` manually, but this is
  not discoverable and should not be needed.

### 6. STABILITY INDICATORS

- The commit follows the exact same pattern as **5+ previous similar
  commits** (SONiX AK870 PRO, hfd.cn/WKB603, Jamesdonkey/A3R, Hailuck,
  the original non-apple keyboards mechanism).
- Signed off by the HID subsystem maintainer (Jiri Kosina).
- The pattern has been in the kernel since v6.0 and is well understood.

### 7. DEPENDENCY CHECK

- **No dependencies**. The `non_apple_keyboards[]` array and
  `apple_is_non_apple_keyboard()` function exist in all relevant stable
  trees.
- The patch applies cleanly to any tree that already has the "SONiX
  AK870 PRO" entry (or can trivially be adjusted if that entry isn't
  present — it's just adding a line to an array).

### 8. PRECEDENT

This is identical in nature to the "SONiX AK870 PRO" (743c81cdc98fd),
"hfd.cn/WKB603" (df83a0df820b9), "Hailuck" (c4444d8749f69), and
"Jamesdonkey/A3R" (113f736655e4f) commits. All follow the same one-line-
addition pattern to the same array.

### Summary

This is a textbook hardware quirk addition — a single line of data added
to an existing mechanism that fixes broken function keys for a specific
keyboard model. It has zero risk of regression, zero dependencies beyond
existing infrastructure, fixes a real user-facing problem, and follows a
well-established pattern with multiple precedents. This is exactly the
kind of commit that stable trees exist to carry.

**YES**

 drivers/hid/hid-apple.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/hid/hid-apple.c b/drivers/hid/hid-apple.c
index 57da4f86a9fa7..233e367cce1d1 100644
--- a/drivers/hid/hid-apple.c
+++ b/drivers/hid/hid-apple.c
@@ -354,6 +354,7 @@ static const struct apple_key_translation swapped_fn_leftctrl_keys[] = {
 };
 
 static const struct apple_non_apple_keyboard non_apple_keyboards[] = {
+	{ "SONiX KN85 Keyboard" },
 	{ "SONiX USB DEVICE" },
 	{ "SONiX AK870 PRO" },
 	{ "Keychron" },
-- 
2.51.0