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 // disable when errors occur 255 times.
  19 #define ERROR_RETURN() do { \
  20     if (ps2_error) { \
  21         if (ps2_mouse_error_count < 255) { \
  22             ps2_mouse_error_count++; \
  23         } else { \
  24             ps2_mouse_error_count = 0; \
  25             ps2_mouse_enable = false; \
  26         } \
  27         return ps2_error; \
  28     } \
  29 } while (0)
  30
  31
  32 /*
  33 TODO
  34 ----
  35 - Stream mode
  36 - Tracpoint command support: needed
  37 - Middle button + move = Wheel traslation
  38 */
  39 bool ps2_mouse_enable = true;
  40 uint8_t ps2_mouse_x = 0;
  41 uint8_t ps2_mouse_y = 0;
  42 uint8_t ps2_mouse_btn = 0;
  43 uint8_t ps2_mouse_error_count = 0;
  44
  45 static uint8_t ps2_mouse_btn_prev = 0;
  46
  47
  48 uint8_t ps2_mouse_init(void) {
  49     uint8_t rcv;
  50
  51     if (!ps2_mouse_enable) return 1;
  52
  53     // Reset
  54     rcv = ps2_host_send(0xFF);
  55     print("ps2_mouse_init: send 0xFF: ");
  56     phex(ps2_error); print("\n");
  57     ERROR_RETURN();
  58
  59     // ACK
  60     rcv = ps2_host_recv();
  61     print("ps2_mouse_init: read ACK: ");
  62     phex(rcv); phex(ps2_error); print("\n");
  63     ERROR_RETURN();
  64
  65     // BAT takes some time
  66     _delay_ms(100);
  67     rcv = ps2_host_recv();
  68     print("ps2_mouse_init: read BAT: ");
  69     phex(rcv); phex(ps2_error); print("\n");
  70     ERROR_RETURN();
  71
  72     // Device ID
  73     rcv = ps2_host_recv();
  74     print("ps2_mouse_init: read DevID: ");
  75     phex(rcv); phex(ps2_error); print("\n");
  76     ERROR_RETURN();
  77
  78     // Enable data reporting
  79     ps2_host_send(0xF4);
  80     print("ps2_mouse_init: send 0xF4: ");
  81     phex(ps2_error); print("\n");
  82     ERROR_RETURN();
  83
  84     // ACK
  85     rcv = ps2_host_recv();
  86     print("ps2_mouse_init: read ACK: ");
  87     phex(rcv); phex(ps2_error); print("\n");
  88     ERROR_RETURN();
  89
  90     // Set Remote mode
  91     ps2_host_send(0xF0);
  92     print("ps2_mouse_init: send 0xF0: ");
  93     phex(ps2_error); print("\n");
  94     ERROR_RETURN();
  95
  96     // ACK
  97     rcv = ps2_host_recv();
  98     print("ps2_mouse_init: read ACK: ");
  99     phex(rcv); phex(ps2_error); print("\n");
 100     ERROR_RETURN();
 101
 102     return 0;
 103 }
 104
 105 /*
 106 Data format:
 107     bit: 7       6       5       4       3       2       1       0
 108 -----------------------------------------------------------------------
 109 0   btn: Yovflw  Xovflw  Ysign   Xsign   1       Middle  Right   Left
 110 1   x:   X movement(0-255)
 111 2   y:   Y movement(0-255)
 112 */
 113 uint8_t ps2_mouse_read(void)
 114 {
 115     uint8_t rcv;
 116
 117     if (!ps2_mouse_enable) return 1;
 118
 119     ps2_host_send(0xEB);
 120     ERROR_RETURN();
 121
 122     rcv=ps2_host_recv();
 123     ERROR_RETURN();
 124
 125     if(rcv==0xFA) {
 126         ps2_mouse_btn = ps2_host_recv();
 127         ERROR_RETURN();
 128         ps2_mouse_x = ps2_host_recv();
 129         ERROR_RETURN();
 130         ps2_mouse_y = ps2_host_recv();
 131         ERROR_RETURN();
 132     }
 133     return 0;
 134 }
 135
 136 bool ps2_mouse_changed(void)
 137 {
 138     return (ps2_mouse_x || ps2_mouse_y || (ps2_mouse_btn & PS2_MOUSE_BTN_MASK) != ps2_mouse_btn_prev);
 139 }
 140
 141 #define PS2_MOUSE_SCROLL_BUTTON 0x04
 142 void ps2_mouse_usb_send(void)
 143 {
 144     static bool scrolled = false;
 145
 146     if (!ps2_mouse_enable) return;
 147
 148     if (ps2_mouse_changed()) {
 149         int8_t x, y, v, h;
 150         x = y = v = h = 0;
 151
 152         // convert scale of X, Y: PS/2(-256/255) -> USB(-127/127)
 153         if (ps2_mouse_btn & (1<<PS2_MOUSE_X_SIGN))
 154             x = ps2_mouse_x > 128 ? (int8_t)ps2_mouse_x : -127;
 155         else
 156             x = ps2_mouse_x < 128 ? (int8_t)ps2_mouse_x : 127;
 157
 158         if (ps2_mouse_btn & (1<<PS2_MOUSE_Y_SIGN))
 159             y = ps2_mouse_y > 128 ? (int8_t)ps2_mouse_y : -127;
 160         else
 161             y = ps2_mouse_y < 128 ? (int8_t)ps2_mouse_y : 127;
 162
 163         // Y is needed to reverse
 164         y = -y;
 165
 166         if (ps2_mouse_btn & PS2_MOUSE_SCROLL_BUTTON) {
 167             // scroll
 168             if (x > 0 || x < 0) h = (x > 64 ? 64 : (x < -64 ? -64 :x));
 169             if (y > 0 || y < 0) v = (y > 64 ? 64 : (y < -64 ? -64 :y));
 170             if (h || v) {
 171                 scrolled = true;
 172                 usb_mouse_send(0,0, -v/16, h/16, 0);
 173                 _delay_ms(100);
 174             }
 175         } else if (!scrolled && (ps2_mouse_btn_prev & PS2_MOUSE_SCROLL_BUTTON)) {
 176             usb_mouse_send(0,0,0,0, PS2_MOUSE_SCROLL_BUTTON);
 177             _delay_ms(100);
 178             usb_mouse_send(0,0,0,0, 0);
 179         } else {
 180             scrolled = false;
 181             usb_mouse_send(x, y, 0, 0, ps2_mouse_btn & PS2_MOUSE_BTN_MASK);
 182         }
 183
 184         ps2_mouse_btn_prev = (ps2_mouse_btn & PS2_MOUSE_BTN_MASK);
 185         ps2_mouse_print();
 186     }
 187     ps2_mouse_x = 0;
 188     ps2_mouse_y = 0;
 189     ps2_mouse_btn = 0;
 190 }
 191
 192 void ps2_mouse_print(void)
 193 {
 194     if (!debug_mouse) return;
 195     print("ps2_mouse[btn|x y]: ");
 196     phex(ps2_mouse_btn); print("|");
 197     phex(ps2_mouse_x); print(" ");
 198     phex(ps2_mouse_y); print("\n");
 199 }