src/main/io/usb_cdc_hid.c

   1 /*
   2  * This file is part of Cleanflight and Betaflight.
   3  *
   4  * Cleanflight and Betaflight are free software. You can redistribute
   5  * this software and/or modify this software under the terms of the
   6  * GNU General Public License as published by the Free Software
   7  * Foundation, either version 3 of the License, or (at your option)
   8  * any later version.
   9  *
  10  * Cleanflight and Betaflight are distributed in the hope that they
  11  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  12  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  13  * See the GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this software.
  17  *
  18  * If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <stdbool.h>
  22
  23 #include "platform.h"
  24
  25 #ifdef USE_USB_CDC_HID
  26
  27 #include "common/maths.h"
  28 #include "fc/rc_controls.h"
  29 #include "rx/rx.h"
  30 #include "pg/usb.h"
  31 #include "sensors/battery.h"
  32 #include "usb_cdc_hid.h"
  33
  34 #define USB_CDC_HID_NUM_AXES 8
  35 #define USB_CDC_HID_NUM_BUTTONS 8
  36
  37 #define USB_CDC_HID_RANGE_MIN -127
  38 #define USB_CDC_HID_RANGE_MAX 127
  39
  40 // In the windows joystick driver, the axes are defined as shown in the second column.
  41
  42 const uint8_t hidChannelMapping[] = {
  43     ROLL,     // X
  44     PITCH,    // Y
  45     AUX3,     // Z
  46     YAW,      // X Rotation
  47     AUX1,     // Z Rotation
  48     THROTTLE, // Y Rotation
  49     AUX4,     // Slider
  50     AUX2,     // Dial
  51     AUX5,     // Button 1
  52     AUX6,     // Button 2
  53     AUX7,     // Button 3
  54     AUX8,     // Button 4
  55     AUX9,     // Button 5
  56     AUX10,    // Button 6
  57     AUX11,    // Button 7
  58     AUX12     // Button 8
  59 };
  60
  61 void sendRcDataToHid(void)
  62 {
  63     int8_t report[9];
  64      // Axes
  65     for (unsigned i = 0; i < USB_CDC_HID_NUM_AXES; i++) {
  66         const uint8_t channel = hidChannelMapping[i];
  67         report[i] = scaleRange(constrain(rcData[channel], PWM_RANGE_MIN, PWM_RANGE_MAX), PWM_RANGE_MIN, PWM_RANGE_MAX, USB_CDC_HID_RANGE_MIN, USB_CDC_HID_RANGE_MAX);
  68         if (channel == PITCH) {
  69             // PITCH is inverted in Windows
  70             report[i] = -report[i];
  71         }
  72     }
  73
  74     // Buttons
  75     // Each bit in one byte represents one button so we have 8 buttons in one-byte-data
  76     report[8] = 0;
  77     for (unsigned i = 0; i < USB_CDC_HID_NUM_BUTTONS; i++) {
  78         const uint8_t channel = hidChannelMapping[i + USB_CDC_HID_NUM_AXES];
  79         if (scaleRange(constrain(rcData[channel], PWM_RANGE_MIN, PWM_RANGE_MAX), PWM_RANGE_MIN, PWM_RANGE_MAX, USB_CDC_HID_RANGE_MIN, USB_CDC_HID_RANGE_MAX) > 0) {
  80             report[8] |= (1 << i);
  81         }
  82     }
  83
  84     sendReport((uint8_t*)report, sizeof(report));
  85 }
  86
  87 bool cdcDeviceIsMayBeActive(void)
  88 {
  89     return usbDevConfig()->type == COMPOSITE && usbIsConnected() && (getBatteryState() == BATTERY_NOT_PRESENT || batteryConfig()->voltageMeterSource == VOLTAGE_METER_NONE);
  90 }
  91 #endif