Inital commit

2026-06-14 19:18:06 +02:00
commit 4d15897b87
21 changed files with 1450 additions and 0 deletions
@@ -0,0 +1,4 @@
+add_library(stkshid STATIC platform/win/stk_win.c)
+target_include_directories(stkshid PUBLIC "${CMAKE_SOURCE_DIR}")
+target_compile_features(stkshid PRIVATE c_std_23)
+target_link_libraries(stkshid PRIVATE setupapi hid)
@@ -0,0 +1,124 @@
+#include "stk/stk.h"
+
+#include <windows.h>
+#include <setupapi.h>
+#include <hidsdi.h>
+#include <stdint.h>
+
+#include <stdio.h>
+
+// GUID_DEVINTERFACE_HID from devguid.h
+static const GUID GUID_DEVINTERFACE_HID = {
+    0x4d1e55b2, 0xf16f, 0x11cf,
+    { 0x88, 0xcb, 0x00, 0x11, 0x11, 0x00, 0x00, 0x30 }
+};
+
+// ---------------------------------------------------------------------------
+// Internal state
+// ---------------------------------------------------------------------------
+
+static HANDLE g_handle = INVALID_HANDLE_VALUE;
+
+// ---------------------------------------------------------------------------
+// Platform backend
+// ---------------------------------------------------------------------------
+
+int stk_open(stk_config_t const* config) {
+    if (!config)
+        return -1;
+
+    HDEVINFO info = SetupDiGetClassDevsW(&GUID_DEVINTERFACE_HID, NULL,
+                                          NULL, DIGCF_PRESENT | DIGCF_DEVICEINTERFACE);
+    if (info == INVALID_HANDLE_VALUE)
+        return -1;
+
+    for (DWORD i = 0; ; i++) {
+        SP_DEVICE_INTERFACE_DATA iface = { .cbSize = sizeof(iface) };
+        if (!SetupDiEnumDeviceInterfaces(info, NULL,
+                                         &GUID_DEVINTERFACE_HID, i, &iface))
+            break;
+
+        DWORD buflen = 0;
+        SetupDiGetDeviceInterfaceDetailW(info, &iface, NULL, 0, &buflen, NULL);
+        if (buflen == 0)
+            continue;
+
+        PSP_DEVICE_INTERFACE_DETAIL_DATA_W detail =
+            (PSP_DEVICE_INTERFACE_DETAIL_DATA_W)HeapAlloc(GetProcessHeap(),
+                                                           0, buflen);
+        detail->cbSize = sizeof(SP_DEVICE_INTERFACE_DETAIL_DATA_W);
+
+        if (!SetupDiGetDeviceInterfaceDetailW(info, &iface, detail, buflen,
+                                              &buflen, NULL)) {
+            HeapFree(GetProcessHeap(), 0, detail);
+            continue;
+        }
+
+        HANDLE handle = CreateFileW(detail->DevicePath,
+                                     GENERIC_READ | GENERIC_WRITE,
+                                     FILE_SHARE_READ | FILE_SHARE_WRITE,
+                                     NULL, OPEN_EXISTING, 0,
+                                     NULL);
+
+        HeapFree(GetProcessHeap(), 0, detail);
+
+        if (handle == INVALID_HANDLE_VALUE)
+            continue;
+
+        HIDD_ATTRIBUTES attrs = { .Size = sizeof(attrs) };
+        if (!HidD_GetAttributes(handle, &attrs)) {
+            CloseHandle(handle);
+            continue;
+        }
+
+        if (attrs.VendorID == config->vendor_id &&
+            attrs.ProductID == config->product_id) {
+            g_handle = handle;
+            SetupDiDestroyDeviceInfoList(info);
+            return 0;
+        }
+
+        CloseHandle(handle);
+    }
+
+    SetupDiDestroyDeviceInfoList(info);
+    fprintf(stderr, "stk: device 0x%04X:0x%04X not found\n",
+            config->vendor_id, config->product_id);
+    return -1;
+}
+
+int stk_read(stk_state_t* state) {
+    if (g_handle == INVALID_HANDLE_VALUE)
+        return -1;
+
+    uint8_t buf[64];
+    DWORD bytes = 0;
+
+    if (!ReadFile(g_handle, buf, sizeof(buf), &bytes, NULL))
+        return -1;
+
+    if (bytes < 20)
+        return -1;
+
+    // Parse axes (little-endian 16-bit values, offset by 2 bytes)
+    for (int i = 0; i < STK_NUM_AXES; i++) {
+        size_t off = 2 + (size_t)i * 2;
+        uint16_t val = (uint16_t)buf[off] |
+                       ((uint16_t)buf[off + 1] << 8);
+        state->axes[i] = (int16_t)val;
+    }
+
+    // Parse buttons (byte 1 + bytes 18-19 = 24 bits)
+    state->buttons = (uint32_t)buf[1] |
+                     ((uint32_t)buf[18] << 8) |
+                     ((uint32_t)buf[19] << 16);
+
+    return 0;
+}
+
+void stk_close(void) {
+    if (g_handle != INVALID_HANDLE_VALUE) {
+        CloseHandle(g_handle);
+        g_handle = INVALID_HANDLE_VALUE;
+    }
+}
@@ -0,0 +1,124 @@
+/**
+ * @file stk.h
+ * @brief EdgeTX RC library interface for HID joystick mode.
+ *
+ * Reads raw HID input reports from the EdgeTX radio and exposes
+ * 4 analog axes (sticks + throttle) and 24 digital buttons
+ * (switches, rockers, paddles).
+ *
+ * @par Report layout (20 bytes):
+ * @code
+ *   byte  0      : report ID (0x00)
+ *   byte  1      : buttons bits 0..7
+ *   bytes 2..17  : 8 axes x 16-bit LE (HID usage 0x30..0x37)
+ *   bytes 18..19 : buttons bits 8..23
+ * @endcode
+ *
+ * @par Active axes:
+ * | Index | Usage | Physical control | Rest value |
+ * |-------|-------|-----------------|------------|
+ * | 0     | —     | unused          | always 0   |
+ * | 1     | RX    | right stick X   | ~1024      |
+ * | 2     | RY    | right stick Y   | ~1024      |
+ * | 3     | —     | unused          | always 0   |
+ * | 4     | Z     | left stick Y    | 0..2047    |
+ * | 5     | VR    | left stick X    | ~1024      |
+ * | 6..7  | —     | unused          | always 0   |
+ */
+#pragma once
+
+#include <stdint.h>
+
+// ---------------------------------------------------------------------------
+// Axis range (10-bit ADC on the radio)
+// ---------------------------------------------------------------------------
+
+#define STK_AXIS_MIN   0
+#define STK_AXIS_MAX   2047
+#define STK_AXIS_MID   1024
+
+// ---------------------------------------------------------------------------
+// Default device IDs (EdgeTX radio in HID joystick mode)
+// ---------------------------------------------------------------------------
+
+#define STK_DEFAULT_VID  0x1209
+#define STK_DEFAULT_PID  0x4F54
+
+// ---------------------------------------------------------------------------
+// Configuration
+// ---------------------------------------------------------------------------
+
+typedef struct {
+    uint16_t vendor_id;
+    uint16_t product_id;
+} stk_config_t;
+
+// ---------------------------------------------------------------------------
+// Radio state
+//
+// axes[] holds all 8 HID axes (indices 0-7). Only indices 1, 2, 4, 5
+// are wired to physical controls. The rest stay at 0.
+//
+// buttons is a 24-bit bitmask: bit N set = switch/button N+1 pressed.
+// ---------------------------------------------------------------------------
+
+#define STK_NUM_AXES    8
+#define STK_NUM_BUTTONS 24
+
+typedef struct {
+    int16_t axes[STK_NUM_AXES];
+    uint32_t buttons;
+} stk_state_t;
+
+// ---------------------------------------------------------------------------
+// Convenience accessors for the 4 active axes
+// ---------------------------------------------------------------------------
+
+static inline int16_t stk_right_x(stk_state_t const* s) {
+    return s->axes[1];
+}
+
+static inline int16_t stk_right_y(stk_state_t const* s) {
+    return s->axes[2];
+}
+
+static inline int16_t stk_throttle(stk_state_t const* s) {
+    return s->axes[4];
+}
+
+static inline int16_t stk_left_x(stk_state_t const* s) {
+    return s->axes[5];
+}
+
+// ---------------------------------------------------------------------------
+// Button bitmask helpers (bit 0 = first switch, bit 23 = last)
+// ---------------------------------------------------------------------------
+
+static inline bool stk_button_pressed(stk_state_t const* s,
+                                      uint8_t index) {
+    if (index >= STK_NUM_BUTTONS)
+        return false;
+    return (s->buttons >> index) & 1;
+}
+
+// ---------------------------------------------------------------------------
+// API
+// ---------------------------------------------------------------------------
+
+/**
+ * Open the HID radio device.
+ * config must remain valid for the lifetime of the open session.
+ * Returns 0 on success, -1 on failure.
+ */
+int stk_open(stk_config_t const* config);
+
+/**
+ * Read the current radio state (non-blocking).
+ * Returns 0 on success, -1 on failure or no new data.
+ */
+int stk_read(stk_state_t* state);
+
+/**
+ * Close the radio device. Safe to call multiple times.
+ */
+void stk_close(void);