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#include <io.h>
#include <stdint.h>
#include <stdio.h>
#include <arch/i386/ps2_controller.h>
#define PS2_DATA 0x60 // data port
#define PS2_STATUS 0x64 // status register
#define PS2_COMMAND 0x64 // command register
// set to true if 2nd ps2 port is available
bool ps2SecondaryEnabled = false;
void initialize_ps2_controller() {
inputbuffer_wait();
outb(PS2_COMMAND, 0xAD); // disable devices
inputbuffer_wait();
outb(PS2_COMMAND, 0xA7);
outputbuffer_wait();
inb(PS2_DATA); // flush output buffer
inb(PS2_DATA);
inb(PS2_DATA);
inb(PS2_DATA);
inb(PS2_DATA);
inb(PS2_DATA);
inb(PS2_DATA);
inb(PS2_DATA);
inb(PS2_DATA);
inb(PS2_DATA);
inputbuffer_wait();
outb(PS2_COMMAND, 0x20); // set controller configuration byte
outputbuffer_wait();
uint8_t conconfig = inb(PS2_DATA);
conconfig &= 0b00110100;
inputbuffer_wait();
outb(PS2_COMMAND, 0x60);
inputbuffer_wait();
outb(PS2_DATA, conconfig);
inputbuffer_wait();
outb(PS2_COMMAND, 0xAA); // performs controller self test
outputbuffer_wait();
if (inb(PS2_DATA) == 0xFC) {
printf("PS/2 controller failed self test\n");
}
inputbuffer_wait();
outb(PS2_COMMAND, 0x60); // in case the controller resets from the test
inputbuffer_wait();
outb(PS2_DATA, conconfig);
int portcount = 1;
inputbuffer_wait();
outb(PS2_COMMAND, 0xA8); // check if ps2 controller is dual channel
inputbuffer_wait();
outb(PS2_COMMAND, 0x20);
outputbuffer_wait();
conconfig = inb(PS2_DATA);
if ((conconfig & 0b00100000) == 0b00000000) { // checks if bit 5 is cleared
ps2SecondaryEnabled = true;
//printf("Dual channel PS/2\n");
portcount = 2;
} else {
//printf("Single channel PS/2\n");
}
inputbuffer_wait();
outb(PS2_COMMAND, 0xAB); // tests ps2 ports
outputbuffer_wait();
if (inb(PS2_DATA) != 0x00) {
printf("PS/2 port 1 failed self test\n");
--portcount;
}
if (ps2SecondaryEnabled) {
inputbuffer_wait();
outb(PS2_COMMAND, 0xA9);
outputbuffer_wait();
if (inb(PS2_DATA) != 0x00) {
printf("PS/2 port 2 failed self test\n");
--portcount;
}
}
if (!portcount) {
printf("PS/2 initialization failed\n");
return;
}
conconfig |= 0b00000011;
inputbuffer_wait();
outb(PS2_COMMAND, 0xAE); // enable ps2 ports
conconfig |= 0b00000001;
if (ps2SecondaryEnabled) {
inputbuffer_wait();
outb(PS2_COMMAND, 0xA8);
outb(PS2_COMMAND, 0x60);
conconfig |= 0b00000011;
outb(PS2_DATA, conconfig);
} else {
inputbuffer_wait();
outb(PS2_COMMAND, 0x60);
conconfig |= 0b00000001;
outb(PS2_DATA, conconfig);
}
//ps2_dev_send_command(0, 0xFF); // reset devices
//inb(PS2_DATA);
//io_wait();
if (ps2SecondaryEnabled) {
//ps2_dev_send_command(1, 0xFF);
//inb(PS2_DATA);
//io_wait();
}
//printf("PS/2 controller initialized\n");
}
// waits for input buffer (write) to be filled
void inputbuffer_wait() {
for (int i = 0; i < 15; i++) {
uint8_t status_reg = inb(PS2_STATUS);
if ((status_reg & 0b00000010)) {
return;
}
io_wait();
}
}
// waits for outbut buffer (read) to be filled
void outputbuffer_wait() {
for (int i = 0; i < 15; i++) {
uint8_t status_reg = inb(PS2_STATUS);
if ((status_reg & 0b00000001)) {
return;
}
io_wait();
}
}
// checks if inpbut buffer is set
bool inputbuffer_check() {
uint8_t status_reg = inb(PS2_STATUS);
if ((status_reg & 0b00000010)) {
return true;
} else {
return false;
}
}
bool outputbuffer_check() {
uint8_t status_reg = inb(PS2_STATUS);
if ((status_reg & 0b00000001)) {
return true;
} else {
return false;
}
}
/* Sends a command byte to a ps2 device
Port numbers start from 0 */
int ps2_dev_send_command(int port, unsigned char command) {
//bool commandRecieved = false;
switch (port)
{
case 0:
for (int i = 0; i < 5; i++) {
uint8_t status_reg = inb(PS2_STATUS);
if ((status_reg & 0b00000010) == 0b00000000) {
outb(PS2_DATA, command);
return 0;
}
inb(PS2_DATA);
io_wait();
}
return 1; // error returned if timeout expires
case 1:
outb(PS2_COMMAND, 0xD4);
for (int i = 0; i < 5; i++) {
uint8_t status_reg = inb(PS2_STATUS);
if ((status_reg & 0b00000010) == 0b00000000) {
outb(PS2_DATA, command);
return 0;
}
inb(PS2_DATA);
io_wait();
}
return 1;
default:
return 2; // out of port range
}
}
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