ps2/ps2.cpp

   1 #include "ps2.hpp"
   2
   3 PS2Device::~PS2Device(void)
   4 {
   5 }
   6
   7 uint32_t PS2Device::read(void)
   8 {
   9     int val, index;
  10
  11     if (this->count == 0) {
  12         /* NOTE: if no data left, we return the last keyboard one
  13            (needed for EMM386) */
  14         /* XXX: need a timer to do things correctly */
  15         index = this->rptr - 1;
  16         if (index < 0) {
  17             index = PS2_QUEUE_SIZE - 1;
  18         }
  19         val = this->data[index];
  20     } else {
  21         val = this->data[this->rptr];
  22         if (++this->rptr == PS2_QUEUE_SIZE) {
  23             this->rptr = 0;
  24         }
  25         this->count--;
  26         /* reading deasserts IRQ */
  27         this->irq.lower();
  28         if (this->count != 0) {
  29             /* reassert IRQs if data left */
  30             this->irq.raise();
  31         }
  32     }
  33     return val;
  34 }
  35
  36 void PS2Device::queue(int b)
  37 {
  38     if (this->count >= PS2_QUEUE_SIZE) {
  39         return;
  40     }
  41     this->data[this->wptr] = b;
  42     if (++this->wptr == PS2_QUEUE_SIZE) {
  43         this->wptr = 0;
  44     }
  45     this->count++;
  46     this->irq.raise();
  47 }
  48
  49 void PS2Device::marshal(Marshaller *m, const char *name)
  50 {
  51     m->start_struct(name, "PS2Device");
  52     ::marshal(m, "irq", &this->irq);
  53     ::marshal(m, "write_cmd", &this->write_cmd);
  54     ::marshal_array(m, "data", this->data, PS2_QUEUE_SIZE);
  55     ::marshal(m, "rptr", &this->rptr);
  56     ::marshal(m, "wptr", &this->wptr);
  57     ::marshal(m, "count", &this->count);
  58     m->end_struct();
  59 }