Re: [PATCH v4] HID: multitouch: add support for Goodix GXTP7863 touchpad
From: Ruzal <hidden>
Date: 2026-09-19 09:23:53
Also in:
lkml
Subsystem:
hid core layer, the rest · Maintainers:
Jiri Kosina, Benjamin Tissoires, Linus Torvalds
On 9/18/26 9:01 PM, Ruzal wrote:
Both descriptor-level approaches confirm what you suspected: modifying the descriptor still leaves the application collection instantiated as an empty/ broken input node, which trips up libinput and blocks the compositor event loop for ~15 seconds.
Hi Benjamin, Quick update on the stall and a tested quirk fix: The userspace stall happens because unrecognized vendor pages hit `unknown:` in hid-input.c:1420 (`map_abs(ABS_MISC)`). This sets EV_ABS, causing hidinput_has_been_populated() to return true and register an anomalous node with only ABS_MISC, which trips up libinput. Instead of touching the descriptor, we can handle this via hid-multitouch: - Add MT_QUIRK_IGNORE_VENDOR_TELEMETRY to drop HID_UP_HPVENDOR2 in mt_input_mapping(). - Add MT_CLS_GOODIX (mirroring MT_CLS_WIN_8 quirks). - Bind with HID_GROUP_MULTITOUCH_WIN_8 in mt_devices[] (preserving INPUT_PER_APP). This drops the phantom input node while leaving raw reports on /dev/hidraw intact. I built the module and tested loading it: /proc/bus/input/devices no longer creates the UNKNOWN node, and /dev/hidraw0 remains available. Diff: --- drivers/hid/hid-ids.h | 1 + drivers/hid/hid-multitouch.c | 27 +++++++++++++++++++++++++++ 2 files changed, 28 insertions(+)
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index b3aca5aa9176..d0850a98c9f8 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h@@ -567,6 +567,7 @@ #define USB_DEVICE_ID_GENERAL_TOUCH_WIN8_PIT_E100 0xe100 #define I2C_VENDOR_ID_GOODIX 0x27c6 +#define I2C_DEVICE_ID_GOODIX_01E0 0x01e0 #define I2C_DEVICE_ID_GOODIX_01E8 0x01e8 #define I2C_DEVICE_ID_GOODIX_01E9 0x01e9 #define I2C_DEVICE_ID_GOODIX_01F0 0x01f0
diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 451c7324e6a0..2e973a3b652b 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c@@ -79,6 +79,7 @@ MODULE_LICENSE("GPL"); #define MT_QUIRK_APPLE_TOUCHBAR BIT(23) #define MT_QUIRK_YOGABOOK9I BIT(24) #define MT_QUIRK_KEEP_LATENCY_ON_CLOSE BIT(25) +#define MT_QUIRK_IGNORE_VENDOR_TELEMETRY BIT(26) #define MT_INPUTMODE_TOUCHSCREEN 0x02 #define MT_INPUTMODE_TOUCHPAD 0x03
@@ -235,6 +236,7 @@ static void mt_post_parse(struct mt_device *td, struct mt_application *app); #define MT_CLS_APPLE_TOUCHBAR 0x0114 #define MT_CLS_YOGABOOK9I 0x0115 #define MT_CLS_EGALAX_P80H84 0x0116 +#define MT_CLS_GOODIX 0x0117 #define MT_CLS_SIS 0x0457 #define MT_DEFAULT_MAXCONTACT 10
@@ -457,6 +459,15 @@ static const struct mt_class mt_classes[] = { MT_QUIRK_IGNORE_DUPLICATES | MT_QUIRK_CONTACT_CNT_ACCURATE, }, + { .name = MT_CLS_GOODIX, + .quirks = MT_QUIRK_ALWAYS_VALID | + MT_QUIRK_IGNORE_DUPLICATES | + MT_QUIRK_HOVERING | + MT_QUIRK_CONTACT_CNT_ACCURATE | + MT_QUIRK_STICKY_FINGERS | + MT_QUIRK_WIN8_PTP_BUTTONS | + MT_QUIRK_IGNORE_VENDOR_TELEMETRY, + .export_all_inputs = true }, { } };
@@ -1524,6 +1535,17 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi, return 1; } + /* + * Goodix FreeTouch devices emit a periodic heartbeat on vendor + * page 0xFF01 which hid-input would otherwise map to + * KEY_MICMUTE / KEY_BRIGHTNESS*, creating a phantom keyboard. + * Drop it here so no input node is exported; the report remains + * available through hidraw. + */ + if ((application->quirks & MT_QUIRK_IGNORE_VENDOR_TELEMETRY) && + (usage->hid & HID_USAGE_PAGE) == HID_UP_HPVENDOR2) + return -1; + if (rdata->is_mt_collection) return mt_touch_input_mapping(hdev, hi, field, usage, bit, max, application);
@@ -2457,6 +2479,11 @@ static const struct hid_device_id mt_devices[] = { HID_DEVICE(BUS_I2C, HID_GROUP_ANY, I2C_VENDOR_ID_GOODIX, I2C_DEVICE_ID_GOODIX_01E9) }, + /* Goodix GXTP7863 device with FreeTouch heartbeat on page 0xFF01 */ + { .driver_data = MT_CLS_GOODIX, + HID_DEVICE(BUS_I2C, HID_GROUP_MULTITOUCH_WIN_8, I2C_VENDOR_ID_GOODIX, + I2C_DEVICE_ID_GOODIX_01E0) }, + /* GoodTouch panels */ { .driver_data = MT_CLS_NSMU, MT_USB_DEVICE(USB_VENDOR_ID_GOODTOUCH,
If this approach looks good to you, I can formally submit it as [PATCH v5]. Cheers, Ruzal