ref: e81c54ba2ecc673a4d5f8aed0e9b52841fe07b0d
dir: /os/pc/devkbd.c/
/*
* keyboard input
*/
#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "../port/error.h"
enum {
Data= 0x60, /* data port */
Status= 0x64, /* status port */
Inready= 0x01, /* input character ready */
Outbusy= 0x02, /* output busy */
Sysflag= 0x04, /* system flag */
Cmddata= 0x08, /* cmd==0, data==1 */
Inhibit= 0x10, /* keyboard/mouse inhibited */
Minready= 0x20, /* mouse character ready */
Rtimeout= 0x40, /* general timeout */
Parity= 0x80,
Cmd= 0x64, /* command port (write only) */
};
enum
{
/* controller command byte */
Cscs1= (1<<6), /* scan code set 1 */
Cauxdis= (1<<5), /* mouse disable */
Ckbddis= (1<<4), /* kbd disable */
Csf= (1<<2), /* system flag */
Cauxint= (1<<1), /* mouse interrupt enable */
Ckbdint= (1<<0), /* kbd interrupt enable */
};
enum {
Qdir,
Qscancode,
Qleds,
};
static Dirtab kbdtab[] = {
".", {Qdir, 0, QTDIR}, 0, 0555,
"scancode", {Qscancode, 0}, 0, 0440,
"leds", {Qleds, 0}, 0, 0220,
};
static Lock i8042lock;
static uchar ccc;
static void (*auxputc)(int, int);
static int nokbd = 1; /* flag: no PS/2 keyboard */
static struct {
Ref ref;
Queue *q;
} kbd;
/*
* wait for output no longer busy
*/
static int
outready(void)
{
int tries;
for(tries = 0; (inb(Status) & Outbusy); tries++){
if(tries > 500)
return -1;
delay(2);
}
return 0;
}
/*
* wait for input
*/
static int
inready(void)
{
int tries;
for(tries = 0; !(inb(Status) & Inready); tries++){
if(tries > 500)
return -1;
delay(2);
}
return 0;
}
/*
* ask 8042 to reset the machine
*/
void
i8042reset(void)
{
int i, x;
if(nokbd)
return;
*((ushort*)KADDR(0x472)) = 0x1234; /* BIOS warm-boot flag */
/*
* newer reset the machine command
*/
outready();
outb(Cmd, 0xFE);
outready();
/*
* Pulse it by hand (old somewhat reliable)
*/
x = 0xDF;
for(i = 0; i < 5; i++){
x ^= 1;
outready();
outb(Cmd, 0xD1);
outready();
outb(Data, x); /* toggle reset */
delay(100);
}
}
int
i8042auxcmd(int cmd)
{
unsigned int c;
int tries;
c = 0;
tries = 0;
ilock(&i8042lock);
do{
if(tries++ > 2)
break;
if(outready() < 0)
break;
outb(Cmd, 0xD4);
if(outready() < 0)
break;
outb(Data, cmd);
if(outready() < 0)
break;
if(inready() < 0)
break;
c = inb(Data);
} while(c == 0xFE || c == 0);
iunlock(&i8042lock);
if(c != 0xFA){
print("i8042: %2.2ux returned to the %2.2ux command (pc=%#p)\n",
c, cmd, getcallerpc(&cmd));
return -1;
}
return 0;
}
/*
* set keyboard's leds for lock states (scroll, numeric, caps).
*
* at least one keyboard (from Qtronics) also sets its numeric-lock
* behaviour to match the led state, though it has no numeric keypad,
* and some BIOSes bring the system up with numeric-lock set and no
* setting to change that. this combination steals the keys for these
* characters and makes it impossible to generate them: uiolkjm&*().
* thus we'd like to be able to force the numeric-lock led (and behaviour) off.
*/
static void
setleds(int leds)
{
static int old = -1;
if(nokbd || leds == old)
return;
leds &= 7;
ilock(&i8042lock);
for(;;){
if(outready() < 0)
break;
outb(Data, 0xed); /* `reset keyboard lock states' */
if(outready() < 0)
break;
outb(Data, leds);
if(outready() < 0)
break;
old = leds;
break;
}
iunlock(&i8042lock);
}
/*
* keyboard interrupt
*/
char kickpanic[3] = {0};
static void
i8042intr(Ureg*, void*)
{
int s, c;
uchar b;
/*
* get status
*/
ilock(&i8042lock);
s = inb(Status);
if(!(s&Inready)){
iunlock(&i8042lock);
return;
}
/*
* get the character
*/
c = inb(Data);
iunlock(&i8042lock);
/*
* if it's the aux port...
*/
if(s & Minready){
if(auxputc != nil)
auxputc(c, 0);
return;
}
b = c & 0xff;
qproduce(kbd.q, &b, 1);
/* iprint("i8042intr b %d %c 0x%x\n", b, b, b); */
kbdprocesschar(b); /* hack until kbdfs is built */
}
void
i8042auxenable(void (*putc)(int, int))
{
static char err[] = "i8042: aux init failed\n";
ilock(&i8042lock);
/* enable kbd/aux xfers and interrupts */
ccc &= ~Cauxdis;
ccc |= Cauxint;
if(outready() < 0)
print(err);
outb(Cmd, 0x60); /* write control register */
if(outready() < 0)
print(err);
outb(Data, ccc);
if(outready() < 0)
print(err);
outb(Cmd, 0xA8); /* auxiliary device enable */
if(outready() < 0){
print(err);
iunlock(&i8042lock);
return;
}
auxputc = putc;
intrenable(IrqAUX, i8042intr, 0, BUSUNKNOWN, "kbdaux");
iunlock(&i8042lock);
}
static void
kbdpoll(void)
{
if(nokbd || qlen(kbd.q) > 0)
return;
i8042intr(0, 0);
}
static void
kbdshutdown(void)
{
if(nokbd)
return;
/* disable kbd and aux xfers and interrupts */
ccc &= ~(Ckbdint|Cauxint);
ccc |= (Cauxdis|Ckbddis);
outready();
outb(Cmd, 0x60);
outready();
outb(Data, ccc);
outready();
}
static Chan *
kbdattach(char *spec)
{
return devattach(L'b', spec);
}
static Walkqid*
kbdwalk(Chan *c, Chan *nc, char **name, int nname)
{
return devwalk(c, nc, name, nname, kbdtab, nelem(kbdtab), devgen);
}
static int
kbdstat(Chan *c, uchar *dp, int n)
{
return devstat(c, dp, n, kbdtab, nelem(kbdtab), devgen);
}
static Chan*
kbdopen(Chan *c, u32 omode)
{
if(!iseve())
error(Eperm);
if(c->qid.path == Qscancode){
if(waserror()){
decref(&kbd.ref);
nexterror();
}
if(incref(&kbd.ref) != 1)
error(Einuse);
c = devopen(c, omode, kbdtab, nelem(kbdtab), devgen);
poperror();
return c;
}
return devopen(c, omode, kbdtab, nelem(kbdtab), devgen);
}
static void
kbdclose(Chan *c)
{
if((c->flag & COPEN) && c->qid.path == Qscancode)
decref(&kbd.ref);
}
static Block*
kbdbread(Chan *c, s32 n, u32 off)
{
if(c->qid.path == Qscancode){
kbdpoll();
return qbread(kbd.q, n);
}
return devbread(c, n, off);
}
static s32
kbdread(Chan *c, void *a, s32 n, s64)
{
if(c->qid.path == Qscancode){
kbdpoll();
return qread(kbd.q, a, n);
}
if(c->qid.path == Qdir)
return devdirread(c, a, n, kbdtab, nelem(kbdtab), devgen);
error(Egreg);
return 0;
}
static s32
kbdwrite(Chan *c, void *a, s32 n, s64)
{
char tmp[8+1], *p;
if(c->qid.path != Qleds)
error(Egreg);
p = tmp + n;
if(n >= sizeof(tmp))
p = tmp + sizeof(tmp)-1;
memmove(tmp, a, p - tmp);
*p = 0;
setleds(atoi(tmp));
return n;
}
static void
kbdreset(void)
{
static char initfailed[] = "i8042: kbd init failed\n";
int c, try;
kbd.q = qopen(1024, Qcoalesce, 0, 0);
if(kbd.q == nil)
panic("kbdreset");
qnoblock(kbd.q, 1);
/* wait for a quiescent controller */
try = 1000;
while(try-- > 0 && (c = inb(Status)) & (Outbusy | Inready)) {
if(c & Inready)
inb(Data);
delay(1);
}
if (try <= 0) {
print(initfailed);
return;
}
/* get current controller command byte */
outb(Cmd, 0x20);
if(inready() < 0){
print("i8042: can't read ccc\n");
ccc = 0;
} else
ccc = inb(Data);
/* enable kbd xfers and interrupts */
ccc &= ~Ckbddis;
ccc |= Csf | Ckbdint | Cscs1;
/* disable ps2 mouse */
ccc &= ~Cauxint;
ccc |= Cauxdis;
if(outready() < 0) {
print(initfailed);
return;
}
outb(Cmd, 0x60);
outready();
outb(Data, ccc);
outready();
nokbd = 0;
ioalloc(Cmd, 1, 0, "i8042.cs");
ioalloc(Data, 1, 0, "i8042.data");
intrenable(IrqKBD, i8042intr, 0, BUSUNKNOWN, "kbd");
}
Dev kbddevtab = {
L'b',
"kbd",
kbdreset,
devinit,
kbdshutdown,
kbdattach,
kbdwalk,
kbdstat,
kbdopen,
devcreate,
kbdclose,
kbdread,
kbdbread,
kbdwrite,
devbwrite,
devremove,
devwstat,
};