blob: 87aa02ee11dbbf97534e512a2908dc3c97827c99 [file] [log] [blame]
// Support for handling the PS/2 mouse/keyboard ports.
//
// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
// Several ideas taken from code Copyright (c) 1999-2004 Vojtech Pavlik
//
// This file may be distributed under the terms of the GNU LGPLv3 license.
#include "ioport.h" // inb
#include "util.h" // dprintf
#include "biosvar.h" // GET_EBDA
#include "ps2port.h" // kbd_command
/****************************************************************
* Low level i8042 commands.
****************************************************************/
// Timeout value.
#define I8042_CTL_TIMEOUT 10000
#define I8042_BUFFER_SIZE 16
static int
i8042_wait_read(void)
{
dprintf(7, "i8042_wait_read\n");
int i;
for (i=0; i<I8042_CTL_TIMEOUT; i++) {
u8 status = inb(PORT_PS2_STATUS);
if (status & I8042_STR_OBF)
return 0;
udelay(50);
}
dprintf(1, "i8042 timeout on wait read\n");
return -1;
}
static int
i8042_wait_write(void)
{
dprintf(7, "i8042_wait_write\n");
int i;
for (i=0; i<I8042_CTL_TIMEOUT; i++) {
u8 status = inb(PORT_PS2_STATUS);
if (! (status & I8042_STR_IBF))
return 0;
udelay(50);
}
dprintf(1, "i8042 timeout on wait write\n");
return -1;
}
int
i8042_flush(void)
{
dprintf(7, "i8042_flush\n");
int i;
for (i=0; i<I8042_BUFFER_SIZE; i++) {
u8 status = inb(PORT_PS2_STATUS);
if (! (status & I8042_STR_OBF))
return 0;
udelay(50);
u8 data = inb(PORT_PS2_DATA);
dprintf(7, "i8042 flushed %x (status=%x)\n", data, status);
}
dprintf(1, "i8042 timeout on flush\n");
return -1;
}
static int
__i8042_command(int command, u8 *param)
{
int receive = (command >> 8) & 0xf;
int send = (command >> 12) & 0xf;
// Send the command.
int ret = i8042_wait_write();
if (ret)
return ret;
outb(command, PORT_PS2_STATUS);
// Send parameters (if any).
int i;
for (i = 0; i < send; i++) {
ret = i8042_wait_write();
if (ret)
return ret;
outb(param[i], PORT_PS2_DATA);
}
// Receive parameters (if any).
for (i = 0; i < receive; i++) {
ret = i8042_wait_read();
if (ret)
return ret;
param[i] = inb(PORT_PS2_DATA);
dprintf(7, "i8042 param=%x\n", param[i]);
}
return 0;
}
int
i8042_command(int command, u8 *param)
{
dprintf(7, "i8042_command cmd=%x\n", command);
int ret = __i8042_command(command, param);
if (ret)
dprintf(2, "i8042 command %x failed\n", command);
return ret;
}
static int
i8042_kbd_write(u8 c)
{
dprintf(7, "i8042_kbd_write c=%d\n", c);
int ret = i8042_wait_write();
if (! ret)
outb(c, PORT_PS2_DATA);
return ret;
}
static int
i8042_aux_write(u8 c)
{
return i8042_command(I8042_CMD_AUX_SEND, &c);
}
/****************************************************************
* Device commands.
****************************************************************/
#define PS2_RET_ACK 0xfa
#define PS2_RET_NAK 0xfe
static int
ps2_recvbyte(int aux, int needack, int timeout)
{
u64 end = calc_future_tsc(timeout);
for (;;) {
u8 status = inb(PORT_PS2_STATUS);
if (status & I8042_STR_OBF) {
u8 data = inb(PORT_PS2_DATA);
dprintf(7, "ps2 read %x\n", data);
if (!!(status & I8042_STR_AUXDATA) == aux) {
if (!needack)
return data;
if (data == PS2_RET_ACK)
return data;
if (data == PS2_RET_NAK) {
dprintf(1, "Got ps2 nak (status=%x); continuing\n", status);
return data;
}
}
// This data not for us - XXX - just discard it for now.
dprintf(1, "Discarding ps2 data %x (status=%x)\n", data, status);
}
if (check_time(end)) {
dprintf(1, "ps2_recvbyte timeout\n");
return -1;
}
yield();
}
}
static int
ps2_sendbyte(int aux, u8 command, int timeout)
{
dprintf(7, "ps2_sendbyte aux=%d cmd=%x\n", aux, command);
int ret;
if (aux)
ret = i8042_aux_write(command);
else
ret = i8042_kbd_write(command);
if (ret)
return ret;
// Read ack.
ret = ps2_recvbyte(aux, 1, timeout);
if (ret < 0)
return ret;
return 0;
}
static int
ps2_command(int aux, int command, u8 *param)
{
int ret2;
int receive = (command >> 8) & 0xf;
int send = (command >> 12) & 0xf;
// Disable interrupts and keyboard/mouse.
u8 ps2ctr = GET_EBDA(ps2ctr);
u8 newctr = ps2ctr;
if (aux)
newctr |= I8042_CTR_KBDDIS;
else
newctr |= I8042_CTR_AUXDIS;
newctr &= ~(I8042_CTR_KBDINT|I8042_CTR_AUXINT);
dprintf(6, "i8042 ctr old=%x new=%x\n", ps2ctr, newctr);
int ret = i8042_command(I8042_CMD_CTL_WCTR, &newctr);
if (ret)
return ret;
if (command == ATKBD_CMD_RESET_BAT) {
// Reset is special wrt timeouts.
// Send command.
ret = ps2_sendbyte(aux, command, 1000);
if (ret)
goto fail;
// Receive parameters.
ret = ps2_recvbyte(aux, 0, 4000);
if (ret < 0)
goto fail;
param[0] = ret;
ret = ps2_recvbyte(aux, 0, 100);
if (ret < 0)
// Some devices only respond with one byte on reset.
ret = 0;
param[1] = ret;
} else {
// Send command.
ret = ps2_sendbyte(aux, command, 200);
if (ret)
goto fail;
// Send parameters (if any).
int i;
for (i = 0; i < send; i++) {
ret = ps2_sendbyte(aux, param[i], 200);
if (ret)
goto fail;
}
// Receive parameters (if any).
for (i = 0; i < receive; i++) {
ret = ps2_recvbyte(aux, 0, 500);
if (ret < 0)
goto fail;
param[i] = ret;
}
}
ret = 0;
fail:
// Restore interrupts and keyboard/mouse.
ret2 = i8042_command(I8042_CMD_CTL_WCTR, &ps2ctr);
if (ret2)
return ret2;
return ret;
}
int
kbd_command(int command, u8 *param)
{
dprintf(7, "kbd_command cmd=%x\n", command);
int ret = ps2_command(0, command, param);
if (ret)
dprintf(2, "keyboard command %x failed\n", command);
return ret;
}
int
aux_command(int command, u8 *param)
{
dprintf(7, "aux_command cmd=%x\n", command);
int ret = ps2_command(1, command, param);
if (ret)
dprintf(2, "mouse command %x failed\n", command);
return ret;
}