ps2_mouse.c

   1 #include <stdbool.h>
   2 #include<avr/io.h>
   3 #include<util/delay.h>
   4 #include "ps2.h"
   5 #include "ps2_mouse.h"
   6 #include "usb_mouse.h"
   7
   8 #define PS2_MOUSE_DEBUG
   9 #ifdef PS2_MOUSE_DEBUG
  10 #   include "print.h"
  11 #   include "debug.h"
  12 #else
  13 #   define print(s)
  14 #   define phex(h)
  15 #   define phex16(h)
  16 #endif
  17
  18 /*
  19 TODO
  20 ----
  21 - Error handling
  22 - Stream mode
  23 - Tracpoint command support: needed
  24 - Middle button + move = Wheel traslation
  25 */
  26 uint8_t ps2_mouse_x = 0;
  27 uint8_t ps2_mouse_y = 0;
  28 uint8_t ps2_mouse_btn = 0;
  29 uint8_t ps2_mouse_error_count = 0;
  30 static uint8_t ps2_mouse_btn_prev = 0;
  31
  32 void ps2_mouse_init(void) {
  33     uint8_t rcv;
  34
  35     // Reset
  36     rcv = ps2_host_send(0xFF);
  37     print("ps2_mouse_init: send 0xFF: ");
  38     phex(ps2_error); print("\n");
  39
  40     // ACK
  41     rcv = ps2_host_recv();
  42     print("ps2_mouse_init: read ACK: ");
  43     phex(rcv); phex(ps2_error); print("\n");
  44
  45     // BAT takes some time
  46     _delay_ms(100);
  47     rcv = ps2_host_recv();
  48     print("ps2_mouse_init: read BAT: ");
  49     phex(rcv); phex(ps2_error); print("\n");
  50
  51     // Device ID
  52     rcv = ps2_host_recv();
  53     print("ps2_mouse_init: read DevID: ");
  54     phex(rcv); phex(ps2_error); print("\n");
  55
  56     // Enable data reporting
  57     ps2_host_send(0xF4);
  58     print("ps2_mouse_init: send 0xF4: ");
  59     phex(ps2_error); print("\n");
  60
  61     // ACK
  62     rcv = ps2_host_recv();
  63     print("ps2_mouse_init: read ACK: ");
  64     phex(rcv); phex(ps2_error); print("\n");
  65
  66     // Set Remote mode
  67     ps2_host_send(0xF0);
  68     print("ps2_mouse_init: send 0xF0: ");
  69     phex(ps2_error); print("\n");
  70
  71     // ACK
  72     rcv = ps2_host_recv();
  73     print("ps2_mouse_init: read ACK: ");
  74     phex(rcv); phex(ps2_error); print("\n");
  75
  76     if (ps2_error) ps2_mouse_error_count++;
  77 }
  78
  79 /*
  80 Data format:
  81     bit: 7       6       5       4       3       2       1       0
  82 -----------------------------------------------------------------------
  83 0   btn: Yovflw  Xovflw  Ysign   Xsign   1       Middle  Right   Left
  84 1   x:   X movement(0-255)
  85 2   y:   Y movement(0-255)
  86 */
  87 void ps2_mouse_read(void)
  88 {
  89     uint8_t rcv;
  90
  91     ps2_host_send(0xEB);
  92     rcv=ps2_host_recv();
  93     if(rcv==0xFA) {
  94         ps2_mouse_btn = ps2_host_recv();
  95         ps2_mouse_x = ps2_host_recv();
  96         ps2_mouse_y = ps2_host_recv();
  97     }
  98     if (ps2_error) ps2_mouse_error_count++;
  99 }
 100
 101 bool ps2_mouse_changed(void)
 102 {
 103     return (ps2_mouse_x || ps2_mouse_y || (ps2_mouse_btn & PS2_MOUSE_BTN_MASK) != ps2_mouse_btn_prev);
 104 }
 105
 106 #define PS2_MOUSE_SCROLL_BUTTON 0x04
 107 void ps2_mouse_usb_send(void)
 108 {
 109     static bool scrolled = false;
 110     if (ps2_mouse_changed()) {
 111         int8_t x, y, v, h;
 112         x = y = v = h = 0;
 113
 114         // convert scale of X, Y: PS/2(-256/255) -> USB(-127/127)
 115         if (ps2_mouse_btn & (1<<PS2_MOUSE_X_SIGN))
 116             x = ps2_mouse_x > 128 ? (int8_t)ps2_mouse_x : -127;
 117         else
 118             x = ps2_mouse_x < 128 ? (int8_t)ps2_mouse_x : 127;
 119
 120         if (ps2_mouse_btn & (1<<PS2_MOUSE_Y_SIGN))
 121             y = ps2_mouse_y > 128 ? (int8_t)ps2_mouse_y : -127;
 122         else
 123             y = ps2_mouse_y < 128 ? (int8_t)ps2_mouse_y : 127;
 124
 125         // Y is needed to reverse
 126         y = -y;
 127
 128         if (ps2_mouse_btn & PS2_MOUSE_SCROLL_BUTTON) {
 129             // scroll
 130             if (x > 0 || x < 0) h = (x > 64 ? 64 : (x < -64 ? -64 :x));
 131             if (y > 0 || y < 0) v = (y > 64 ? 64 : (y < -64 ? -64 :y));
 132             if (h || v) {
 133                 scrolled = true;
 134                 usb_mouse_send(0,0, -v/16, h/16, 0);
 135                 _delay_ms(100);
 136             }
 137         } else if (!scrolled && (ps2_mouse_btn_prev & PS2_MOUSE_SCROLL_BUTTON)) {
 138             usb_mouse_send(0,0,0,0, PS2_MOUSE_SCROLL_BUTTON);
 139             _delay_ms(100);
 140             usb_mouse_send(0,0,0,0, 0);
 141         } else {
 142             scrolled = false;
 143             usb_mouse_send(x, y, 0, 0, ps2_mouse_btn & PS2_MOUSE_BTN_MASK);
 144         }
 145
 146         ps2_mouse_btn_prev = (ps2_mouse_btn & PS2_MOUSE_BTN_MASK);
 147         ps2_mouse_print();
 148     }
 149     ps2_mouse_x = 0;
 150     ps2_mouse_y = 0;
 151     ps2_mouse_btn = 0;
 152 }
 153
 154 void ps2_mouse_print(void)
 155 {
 156     if (!debug_mouse) return;
 157     print("ps2_mouse[btn|x y]: ");
 158     phex(ps2_mouse_btn); print("|");
 159     phex(ps2_mouse_x); print(" ");
 160     phex(ps2_mouse_y); print("\n");
 161 }