From: Akira Inoue niyarium@gmail.com
[ Upstream commit a8905238c3bbe13db90065ed74682418f23830c3 ]
Add "Thinkpad X1 Tablet Gen 2 Keyboard" PID to hid-lenovo driver to fix trackpoint not working issue.
Signed-off-by: Akira Inoue niyarium@gmail.com Signed-off-by: Jiri Kosina jkosina@suse.com Signed-off-by: Sasha Levin sashal@kernel.org ---
**YES**
This commit should be backported to stable kernel trees. Here's my extensive analysis:
## Commit Analysis
This commit adds support for the ThinkPad X1 Tablet Thin Keyboard Gen2 by adding its USB device ID (0x60a4) to the hid-lenovo driver. The primary issue being fixed is that the trackpoint (pointing stick) is non-functional without this patch.
## Code Changes Examination
1. **drivers/hid/hid-ids.h**: Adds `USB_DEVICE_ID_LENOVO_X1_TAB2` with value 0x60a4. This follows the existing pattern where X1_TAB is 0x60a3 and X1_TAB3 is 0x60b5.
2. **drivers/hid/hid-lenovo.c**: The device ID is added to 7 locations: - `lenovo_input_mapping()`: Enables X1 tablet keyboard-specific input mappings - `attr_fn_lock_store()`: Enables FnLock LED control functionality - `lenovo_event()`: Handles special key events - `lenovo_led_brightness_set()`: Controls mute/micmute LED indicators - `lenovo_probe()`: Initializes device with tp10ubkbd infrastructure - `lenovo_remove()`: Cleanup handling - `lenovo_devices[]`: Device table entry with HID_GROUP_GENERIC
3. **drivers/hid/hid-multitouch.c**: Adds multitouch support with `MT_CLS_WIN_8_FORCE_MULTI_INPUT` class, consistent with other X1 Tablet devices.
## Stable Backport Criteria
This commit meets all the stable kernel backporting criteria:
1. **Fixes a real bug**: The trackpoint is completely non-functional without this patch, affecting users who own this hardware.
2. **Small and contained**: The changes are minimal - just adding a device ID to existing code paths. No new functionality or architectural changes.
3. **Obviously correct**: The pattern is identical to existing X1 Tablet support (Gen1 and Gen3). The commit follows established conventions.
4. **Low risk**: Cannot affect any other hardware since it's guarded by specific device ID checks.
5. **Hardware enablement**: This is pure hardware enablement for a specific device that doesn't work at all without this patch.
## Comparison with Similar Commits
Looking at the provided similar commits: - Commits adding X1 Tablet Gen3 support (Similar #2) and X12 Tab Gen2 support (Similar #4) were marked YES for backporting - Both fixed similar issues (non-working buttons, trackpoint, FnLock) - This commit follows the exact same pattern
The commit marked NO (Similar #1) only added partial multitouch support without the full hid-lenovo driver integration, which is why it wasn't suitable for stable.
## Conclusion
This is a textbook example of a commit that should be backported to stable kernels. It enables basic functionality (trackpoint) for specific hardware that is completely broken without it, using minimal, well- tested code patterns that cannot regress other devices.
drivers/hid/hid-ids.h | 1 + drivers/hid/hid-lenovo.c | 8 ++++++++ drivers/hid/hid-multitouch.c | 8 +++++++- 3 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h index a8665d57094b2..c0ce11393f0fb 100644 --- a/drivers/hid/hid-ids.h +++ b/drivers/hid/hid-ids.h @@ -807,6 +807,7 @@ #define USB_DEVICE_ID_LENOVO_TPPRODOCK 0x6067 #define USB_DEVICE_ID_LENOVO_X1_COVER 0x6085 #define USB_DEVICE_ID_LENOVO_X1_TAB 0x60a3 +#define USB_DEVICE_ID_LENOVO_X1_TAB2 0x60a4 #define USB_DEVICE_ID_LENOVO_X1_TAB3 0x60b5 #define USB_DEVICE_ID_LENOVO_X12_TAB 0x60fe #define USB_DEVICE_ID_LENOVO_X12_TAB2 0x61ae diff --git a/drivers/hid/hid-lenovo.c b/drivers/hid/hid-lenovo.c index a4062f617ba20..90e8b6a0a873d 100644 --- a/drivers/hid/hid-lenovo.c +++ b/drivers/hid/hid-lenovo.c @@ -473,6 +473,7 @@ static int lenovo_input_mapping(struct hid_device *hdev, return lenovo_input_mapping_tp10_ultrabook_kbd(hdev, hi, field, usage, bit, max); case USB_DEVICE_ID_LENOVO_X1_TAB: + case USB_DEVICE_ID_LENOVO_X1_TAB2: case USB_DEVICE_ID_LENOVO_X1_TAB3: return lenovo_input_mapping_x1_tab_kbd(hdev, hi, field, usage, bit, max); default: @@ -584,6 +585,7 @@ static ssize_t attr_fn_lock_store(struct device *dev, break; case USB_DEVICE_ID_LENOVO_TP10UBKBD: case USB_DEVICE_ID_LENOVO_X1_TAB: + case USB_DEVICE_ID_LENOVO_X1_TAB2: case USB_DEVICE_ID_LENOVO_X1_TAB3: ret = lenovo_led_set_tp10ubkbd(hdev, TP10UBKBD_FN_LOCK_LED, value); if (ret) @@ -779,6 +781,7 @@ static int lenovo_event(struct hid_device *hdev, struct hid_field *field, return lenovo_event_cptkbd(hdev, field, usage, value); case USB_DEVICE_ID_LENOVO_TP10UBKBD: case USB_DEVICE_ID_LENOVO_X1_TAB: + case USB_DEVICE_ID_LENOVO_X1_TAB2: case USB_DEVICE_ID_LENOVO_X1_TAB3: return lenovo_event_tp10ubkbd(hdev, field, usage, value); default: @@ -1062,6 +1065,7 @@ static int lenovo_led_brightness_set(struct led_classdev *led_cdev, break; case USB_DEVICE_ID_LENOVO_TP10UBKBD: case USB_DEVICE_ID_LENOVO_X1_TAB: + case USB_DEVICE_ID_LENOVO_X1_TAB2: case USB_DEVICE_ID_LENOVO_X1_TAB3: ret = lenovo_led_set_tp10ubkbd(hdev, tp10ubkbd_led[led_nr], value); break; @@ -1293,6 +1297,7 @@ static int lenovo_probe(struct hid_device *hdev, break; case USB_DEVICE_ID_LENOVO_TP10UBKBD: case USB_DEVICE_ID_LENOVO_X1_TAB: + case USB_DEVICE_ID_LENOVO_X1_TAB2: case USB_DEVICE_ID_LENOVO_X1_TAB3: ret = lenovo_probe_tp10ubkbd(hdev); break; @@ -1380,6 +1385,7 @@ static void lenovo_remove(struct hid_device *hdev) break; case USB_DEVICE_ID_LENOVO_TP10UBKBD: case USB_DEVICE_ID_LENOVO_X1_TAB: + case USB_DEVICE_ID_LENOVO_X1_TAB2: case USB_DEVICE_ID_LENOVO_X1_TAB3: lenovo_remove_tp10ubkbd(hdev); break; @@ -1430,6 +1436,8 @@ static const struct hid_device_id lenovo_devices[] = { */ { HID_DEVICE(BUS_USB, HID_GROUP_GENERIC, USB_VENDOR_ID_LENOVO, USB_DEVICE_ID_LENOVO_X1_TAB) }, + { HID_DEVICE(BUS_USB, HID_GROUP_GENERIC, + USB_VENDOR_ID_LENOVO, USB_DEVICE_ID_LENOVO_X1_TAB2) }, { HID_DEVICE(BUS_USB, HID_GROUP_GENERIC, USB_VENDOR_ID_LENOVO, USB_DEVICE_ID_LENOVO_X1_TAB3) }, { } diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index 6386043aab0bb..becd4c1ccf93c 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -2110,12 +2110,18 @@ static const struct hid_device_id mt_devices[] = { HID_DEVICE(BUS_I2C, HID_GROUP_GENERIC, USB_VENDOR_ID_LG, I2C_DEVICE_ID_LG_7010) },
- /* Lenovo X1 TAB Gen 2 */ + /* Lenovo X1 TAB Gen 1 */ { .driver_data = MT_CLS_WIN_8_FORCE_MULTI_INPUT, HID_DEVICE(BUS_USB, HID_GROUP_MULTITOUCH_WIN_8, USB_VENDOR_ID_LENOVO, USB_DEVICE_ID_LENOVO_X1_TAB) },
+ /* Lenovo X1 TAB Gen 2 */ + { .driver_data = MT_CLS_WIN_8_FORCE_MULTI_INPUT, + HID_DEVICE(BUS_USB, HID_GROUP_MULTITOUCH_WIN_8, + USB_VENDOR_ID_LENOVO, + USB_DEVICE_ID_LENOVO_X1_TAB2) }, + /* Lenovo X1 TAB Gen 3 */ { .driver_data = MT_CLS_WIN_8_FORCE_MULTI_INPUT, HID_DEVICE(BUS_USB, HID_GROUP_MULTITOUCH_WIN_8,