Add touchpad feature

builddefs/common_features.mk

@@ -855,6 +855,14 @@ ifeq ($(strip $(JOYSTICK_ENABLE)), yes)
     endif
 endif
 
+FRAMEWORK_TOUCHPAD_ENABLE ?= no
+ifeq ($(strip $(FRAMEWORK_TOUCHPAD_ENABLE)), yes)
+    OPT_DEFS += -DFRAMEWORK_TOUCHPAD_ENABLE
+    SRC += $(QUANTUM_DIR)/framework_touchpad.c
+
+    I2C_DRIVER_REQUIRED = yes
+endif
+
 USBPD_ENABLE ?= no
 VALID_USBPD_DRIVER_TYPES = custom vendor
 USBPD_DRIVER ?= vendor

quantum/framework_touchpad.c

@@ -0,0 +1,48 @@
+/* Copyright 2025
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "framework_touchpad.h"
+#include "i2c_master.h"
+#include "print.h"
+
+#define FRAMEWORK_TOUCHPAD_I2C_ADDRESS (0x2c << 1)
+
+void framework_touchpad_init(void) {
+    i2c_init();
+}
+
+void framework_touchpad_task(void) {
+    int     length     = 0;
+    int     status     = I2C_STATUS_SUCCESS;
+    uint8_t buffer[37] = {0};
+    uint8_t report[34] = {0};
+
+    status = i2c_receive(FRAMEWORK_TOUCHPAD_I2C_ADDRESS, buffer, 1, 100);
+    length = buffer[0];
+    if (status != I2C_STATUS_SUCCESS || buffer[0] <= 0) {
+        return;
+    }
+
+    status = i2c_receive(FRAMEWORK_TOUCHPAD_I2C_ADDRESS, buffer, length, 100);
+    if (status != I2C_STATUS_SUCCESS || buffer[2] != 0x01) {
+        return;
+    }
+
+    memcpy(report, buffer + 3, 34);
+
+    void host_framework_touchpad_send(uint8_t(*report)[34]);
+    host_framework_touchpad_send(&report);
+}

quantum/framework_touchpad.h

@@ -0,0 +1,27 @@
+/* Copyright 2025
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+/**
+ * \brief Handle the initialization of the subsystem.
+ */
+void framework_touchpad_init(void);
+
+/**
+ * \brief Handle various subsystem background tasks.
+ */
+void framework_touchpad_task(void);

quantum/keyboard.c

@@ -92,6 +92,9 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #ifdef JOYSTICK_ENABLE
 #    include "joystick.h"
 #endif
+#ifdef FRAMEWORK_TOUCHPAD_ENABLE
+#    include "framework_touchpad.h"
+#endif
 #ifdef HD44780_ENABLE
 #    include "hd44780.h"
 #endif
@@ -469,6 +472,9 @@ void keyboard_init(void) {
 #ifdef JOYSTICK_ENABLE
     joystick_init();
 #endif
+#ifdef FRAMEWORK_TOUCHPAD_ENABLE
+    framework_touchpad_init();
+#endif
 #ifdef SLEEP_LED_ENABLE
     sleep_led_init();
 #endif
@@ -742,6 +748,10 @@ void keyboard_task(void) {
     joystick_task();
 #endif
 
+#ifdef FRAMEWORK_TOUCHPAD_ENABLE
+    framework_touchpad_task();
+#endif
+
 #ifdef BLUETOOTH_ENABLE
     bluetooth_task();
 #endif

quantum/quantum.h

@@ -194,6 +194,10 @@ extern layer_state_t layer_state;
 #    include "digitizer.h"
 #endif
 
+#ifdef FRAMEWORK_TOUCHPAD_ENABLE
+#    include "framework_touchpad.h"
+#endif
+
 #ifdef VIA_ENABLE
 #    include "via.h"
 #endif

tmk_core/protocol.mk

@@ -92,6 +92,14 @@ ifeq ($(strip $(DIGITIZER_ENABLE)), yes)
     endif
 endif
 
+ifeq ($(strip $(FRAMEWORK_TOUCHPAD_ENABLE)), yes)
+    OPT_DEFS += -DFRAMEWORK_TOUCHPAD_ENABLE
+    ifeq ($(strip $(SHARED_EP_ENABLE)), yes)
+        OPT_DEFS += -DFRAMEWORK_TOUCHPAD_SHARED_EP
+        SHARED_EP_ENABLE = yes
+    endif
+endif
+
 ifeq ($(strip $(SHARED_EP_ENABLE)), yes)
     OPT_DEFS += -DSHARED_EP_ENABLE
 endif

tmk_core/protocol/chibios/usb_endpoints.c

@@ -64,6 +64,10 @@ usb_endpoint_in_t usb_endpoints_in[USB_ENDPOINT_IN_COUNT] = {
     [USB_ENDPOINT_IN_DIGITIZER] = QMK_USB_ENDPOINT_IN(USB_EP_MODE_TYPE_INTR, DIGITIZER_EPSIZE, DIGITIZER_IN_EPNUM, DIGITIZER_IN_CAPACITY, NULL, QMK_USB_REPORT_STORAGE_DEFAULT(sizeof(report_digitizer_t))),
 #endif
 
+#if defined(FRAMEWORK_TOUCHPAD_ENABLE) && !defined(FRAMEWORK_TOUCHPAD_SHARED_EP)
+    [USB_ENDPOINT_IN_FRAMEWORK_TOUCHPAD] = QMK_USB_ENDPOINT_IN(USB_EP_MODE_TYPE_INTR, DIGITIZER_EPSIZE, DIGITIZER_IN_EPNUM, DIGITIZER_IN_CAPACITY, NULL, QMK_USB_REPORT_STORAGE_DEFAULT(sizeof(report_digitizer_t))),
+#endif
+
 #if defined(CONSOLE_ENABLE)
 #    if defined(USB_ENDPOINTS_ARE_REORDERABLE)
     [USB_ENDPOINT_IN_CONSOLE] = QMK_USB_ENDPOINT_IN_SHARED(USB_EP_MODE_TYPE_INTR, CONSOLE_EPSIZE, CONSOLE_IN_EPNUM, CONSOLE_IN_CAPACITY, NULL, QMK_USB_REPORT_STORAGE_DEFAULT(CONSOLE_EPSIZE)),
@@ -135,6 +139,10 @@ usb_endpoint_in_lut_t usb_endpoint_interface_lut[TOTAL_INTERFACES] = {
 #if defined(DIGITIZER_ENABLE) && !defined(DIGITIZER_SHARED_EP)
     [DIGITIZER_INTERFACE] = USB_ENDPOINT_IN_DIGITIZER,
 #endif
+
+#if defined(FRAMEWORK_TOUCHPAD_ENABLE) && !defined(FRAMEWORK_TOUCHPAD_SHARED_EP)
+    [FRAMEWORK_TOUCHPAD_INTERFACE] = USB_ENDPOINT_IN_FRAMEWORK_TOUCHPAD,
+#endif
 };
 
 usb_endpoint_out_t usb_endpoints_out[USB_ENDPOINT_OUT_COUNT] = {

tmk_core/protocol/chibios/usb_endpoints.h

@@ -82,6 +82,10 @@ typedef enum {
     USB_ENDPOINT_IN_DIGITIZER,
 #endif
 
+#if defined(FRAMEWORK_TOUCHPAD_ENABLE) && !defined(FRAMEWORK_TOUCHPAD_SHARED_EP)
+    USB_ENDPOINT_IN_FRAMEWORK_TOUCHPAD,
+#endif
+
 #if defined(CONSOLE_ENABLE)
     USB_ENDPOINT_IN_CONSOLE,
 #endif
@@ -116,6 +120,9 @@ typedef enum {
 #    if defined(DIGITIZER_SHARED_EP)
     USB_ENDPOINT_IN_DIGITIZER = USB_ENDPOINT_IN_SHARED,
 #    endif
+#    if defined(FRAMEWORK_TOUCHPAD_SHARED_EP)
+    USB_ENDPOINT_IN_FRAMEWORK_TOUCHPAD = USB_ENDPOINT_IN_SHARED,
+#    endif
 #endif
 } usb_endpoint_in_lut_t;
 

tmk_core/protocol/chibios/usb_main.c

@@ -497,6 +497,12 @@ void send_digitizer(report_digitizer_t *report) {
 #endif
 }
 
+void send_framework_touchpad(report_framework_touchpad_t *report) {
+#ifdef FRAMEWORK_TOUCHPAD_ENABLE
+    send_report(USB_ENDPOINT_IN_FRAMEWORK_TOUCHPAD, report, sizeof(report_framework_touchpad_t));
+#endif
+}
+
 /* ---------------------------------------------------------
  *                   Console functions
  * ---------------------------------------------------------

tmk_core/protocol/host.c

@@ -26,6 +26,10 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #    include "digitizer.h"
 #endif
 
+#ifdef FRAMEWORK_TOUCHPAD_ENABLE
+#    include "framework_touchpad.h"
+#endif
+
 #ifdef JOYSTICK_ENABLE
 #    include "joystick.h"
 #endif
@@ -240,6 +244,23 @@ void host_digitizer_send(digitizer_t *digitizer) {
 
 __attribute__((weak)) void send_digitizer(report_digitizer_t *report) {}
 
+#ifdef FRAMEWORK_TOUCHPAD_ENABLE
+void host_framework_touchpad_send(uint8_t (*data)[34]) {
+    report_framework_touchpad_t report = {
+#    ifdef FRAMEWORK_TOUCHPAD_SHARED_EP
+        .report_id = REPORT_ID_FRAMEWORK_TOUCHPAD,
+#    endif
+        .report = {0},
+    };
+
+    memcpy(report.report, data, 34);
+
+    send_framework_touchpad(&report);
+}
+#endif
+
+__attribute__((weak)) void send_framework_touchpad(report_framework_touchpad_t *report) {}
+
 #ifdef PROGRAMMABLE_BUTTON_ENABLE
 void host_programmable_button_send(uint32_t data) {
     report_programmable_button_t report = {

tmk_core/protocol/host_driver.h

@@ -33,4 +33,5 @@ typedef struct {
 
 void send_joystick(report_joystick_t *report);
 void send_digitizer(report_digitizer_t *report);
+void send_framework_touchpad(report_framework_touchpad_t *report);
 void send_programmable_button(report_programmable_button_t *report);

tmk_core/protocol/lufa/lufa.c

@@ -385,6 +385,11 @@ void EVENT_USB_Device_ConfigurationChanged(void) {
     ConfigSuccess &= Endpoint_ConfigureEndpoint((DIGITIZER_IN_EPNUM | ENDPOINT_DIR_IN), EP_TYPE_INTERRUPT, DIGITIZER_EPSIZE, 1);
 #endif
 
+#if defined(FRAMEWORK_TOUCHPAD_ENABLE) && !defined(FRAMEWORK_TOUCHPAD_SHARED_EP)
+    /* Setup digitizer endpoint */
+    ConfigSuccess &= Endpoint_ConfigureEndpoint((DIGITIZER_IN_EPNUM | ENDPOINT_DIR_IN), EP_TYPE_INTERRUPT, DIGITIZER_EPSIZE, 1);
+#endif
+
     usb_device_state_set_configuration(USB_DeviceState == DEVICE_STATE_Configured, USB_Device_ConfigurationNumber);
 }
 

tmk_core/protocol/report.h

@@ -39,6 +39,7 @@ enum hid_report_ids {
     REPORT_ID_NKRO,
     REPORT_ID_JOYSTICK,
     REPORT_ID_DIGITIZER,
+    REPORT_ID_FRAMEWORK_TOUCHPAD,
     REPORT_ID_COUNT = REPORT_ID_DIGITIZER
 };
 
@@ -232,6 +233,13 @@ typedef struct {
     uint16_t y;
 } PACKED report_digitizer_t;
 
+typedef struct {
+#ifdef FRAMEWORK_TOUCHPAD_SHARED_EP
+    uint8_t report_id;
+#endif
+    uint8_t report[34];
+} PACKED report_framework_touchpad_t;
+
 #if JOYSTICK_AXIS_RESOLUTION > 8
 typedef int16_t joystick_axis_t;
 #else