diff options
Diffstat (limited to 'kernel/arch/x86/ps2_controller.cpp')
| -rw-r--r-- | kernel/arch/x86/ps2_controller.cpp | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/kernel/arch/x86/ps2_controller.cpp b/kernel/arch/x86/ps2_controller.cpp new file mode 100644 index 0000000..9424233 --- /dev/null +++ b/kernel/arch/x86/ps2_controller.cpp @@ -0,0 +1,191 @@ +#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
+ }
+}
\ No newline at end of file |