Orion

/*
 * This file contains the mouse driver.  It generates the /dev/mouse device
 * file, which can be read and returns a structure of the mouse data.
 */

#include <sys/mouse.h>
#include "../drivers.h"
#include "../../proc/proc.h"
#include "../../io.h"

size_t mouse_read(File *file, char *buf, size_t size, off_t offset);

FileOps mouseFileOps = {
	.read = mouse_read,
};

Driver mouseDriver = {
	.major = 11,
	.ops = &mouseFileOps,
	.next = NULL,
};

unsigned char mouseCycle = 0;
char mouseByte[3], mouseX = 0, mouseY = 0;

/* Handle the mouse interrupt */
static void
mouse_handler(InterruptFrame *frame)
{
	mouseByte[mouseCycle++] = inb(0x60);
	if (mouseCycle < 3)
		return;
	mouseCycle = 0;
	mouseX = mouseByte[1];
	mouseY = mouseByte[2];

//	kprintf("Mouse at [%d,%d]", mouseX, mouseY);
}

/* Wait on the mouse */
static inline void
mouse_io_wait(int type)
{
	int time = 100000;
	if (!type) {
		while (time--)
			if ((inb(0x64) & 1) == 1)
				return;
	} else {
		while (time--)
			if ((inb(0x64) & 2) == 0)
				return;
	}
}

/* Write to the mouse */
static inline void
mouse_io_write(char byte)
{
	mouse_io_wait(1);
	outb(0x64, 0xD4);
	mouse_io_wait(1);
	outb(0x60, byte);
}

/* Read from the mouse */
static inline char
mouse_io_read(void)
{
	mouse_io_wait(0);
	return inb(0x60);
}

/* Initialise the mouse */
void
init_mouse(void)
{
	register_driver(&mouseDriver);
	mknod("/dev/mouse", S_IFCHR | 0666, MKDEV(mouseDriver.major, 0));
	register_interrupt(12, mouse_handler);

	char status;
	mouse_io_wait(1);
	outb(0x64, 0xA8);

	/* Enable interrupts */
	mouse_io_wait(1);
	outb(0x64, 0x20);
	mouse_io_wait(0);
	status = inb(0x60) | 2;
	mouse_io_wait(1);
	outb(0x64, 0x60);
	mouse_io_wait(1);
	outb(0x60, status);

	/* Use default settings */
	mouse_io_write(0xF6);
	mouse_io_read();

	/* Enable the mouse */
	mouse_io_write(0xF4);
	mouse_io_read();
}

/* Read the mouse device */
size_t
mouse_read(File *file, char *buf, size_t size, off_t offset)
{
	size_t count = 0;
	while (count < size) {
		*(buf + count++) = mouseByte[0];
		*(buf + count++) = mouseX;
		*(buf + count++) = mouseY;
	}
	return count;
}