freebsd-skq/sys/dev/led/led.c
Alexander Motin 92b7c16c73 MFgraid/head r218174:
Add simple in-kernel API for controlling leds.
2011-03-24 08:56:12 +00:00

333 lines
6.8 KiB
C

/*-
* ----------------------------------------------------------------------------
* "THE BEER-WARE LICENSE" (Revision 42):
* <phk@FreeBSD.org> wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
* ----------------------------------------------------------------------------
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/limits.h>
#include <sys/malloc.h>
#include <sys/ctype.h>
#include <sys/sbuf.h>
#include <sys/queue.h>
#include <dev/led/led.h>
#include <sys/uio.h>
#include <sys/sx.h>
struct ledsc {
LIST_ENTRY(ledsc) list;
char *name;
void *private;
int unit;
led_t *func;
struct cdev *dev;
struct sbuf *spec;
char *str;
char *ptr;
int count;
time_t last_second;
};
static struct unrhdr *led_unit;
static struct mtx led_mtx;
static struct sx led_sx;
static LIST_HEAD(, ledsc) led_list = LIST_HEAD_INITIALIZER(led_list);
static struct callout led_ch;
static MALLOC_DEFINE(M_LED, "LED", "LED driver");
static void
led_timeout(void *p)
{
struct ledsc *sc;
mtx_lock(&led_mtx);
LIST_FOREACH(sc, &led_list, list) {
if (sc->ptr == NULL)
continue;
if (sc->count > 0) {
sc->count--;
continue;
}
if (*sc->ptr == '.') {
sc->ptr = NULL;
continue;
} else if (*sc->ptr == 'U' || *sc->ptr == 'u') {
if (sc->last_second == time_second)
continue;
sc->last_second = time_second;
sc->func(sc->private, *sc->ptr == 'U');
} else if (*sc->ptr >= 'a' && *sc->ptr <= 'j') {
sc->func(sc->private, 0);
sc->count = (*sc->ptr & 0xf) - 1;
} else if (*sc->ptr >= 'A' && *sc->ptr <= 'J') {
sc->func(sc->private, 1);
sc->count = (*sc->ptr & 0xf) - 1;
}
sc->ptr++;
if (*sc->ptr == '\0')
sc->ptr = sc->str;
}
mtx_unlock(&led_mtx);
callout_reset(&led_ch, hz / 10, led_timeout, p);
return;
}
static int
led_state(struct ledsc *sc, struct sbuf **sb, int state)
{
struct sbuf *sb2 = NULL;
sb2 = sc->spec;
sc->spec = *sb;
if (*sb != NULL) {
sc->str = sbuf_data(*sb);
sc->ptr = sc->str;
} else {
sc->str = NULL;
sc->ptr = NULL;
sc->func(sc->private, state);
}
sc->count = 0;
*sb = sb2;
return(0);
}
static int
led_parse(const char *s, struct sbuf **sb, int *state)
{
int i, error;
/*
* Handle "on" and "off" immediately so people can flash really
* fast from userland if they want to
*/
if (*s == '0' || *s == '1') {
*state = *s & 1;
return (0);
}
*state = 0;
*sb = sbuf_new_auto();
if (*sb == NULL)
return (ENOMEM);
switch(s[0]) {
/*
* Flash, default is 100msec/100msec.
* 'f2' sets 200msec/200msec etc.
*/
case 'f':
if (s[1] >= '1' && s[1] <= '9')
i = s[1] - '1';
else
i = 0;
sbuf_printf(*sb, "%c%c", 'A' + i, 'a' + i);
break;
/*
* Digits, flashes out numbers.
* 'd12' becomes -__________-_-______________________________
*/
case 'd':
for(s++; *s; s++) {
if (!isdigit(*s))
continue;
i = *s - '0';
if (i == 0)
i = 10;
for (; i > 1; i--)
sbuf_cat(*sb, "Aa");
sbuf_cat(*sb, "Aj");
}
sbuf_cat(*sb, "jj");
break;
/*
* String, roll your own.
* 'a-j' gives "off" for n/10 sec.
* 'A-J' gives "on" for n/10 sec.
* no delay before repeat
* 'sAaAbBa' becomes _-_--__-
*/
case 's':
for(s++; *s; s++) {
if ((*s >= 'a' && *s <= 'j') ||
(*s >= 'A' && *s <= 'J') ||
*s == 'U' || *s <= 'u' ||
*s == '.')
sbuf_bcat(*sb, s, 1);
}
break;
/*
* Morse.
* '.' becomes _-
* '-' becomes _---
* ' ' becomes __
* '\n' becomes ____
* 1sec pause between repeats
* '... --- ...' -> _-_-_-___---_---_---___-_-_-__________
*/
case 'm':
for(s++; *s; s++) {
if (*s == '.')
sbuf_cat(*sb, "aA");
else if (*s == '-')
sbuf_cat(*sb, "aC");
else if (*s == ' ')
sbuf_cat(*sb, "b");
else if (*s == '\n')
sbuf_cat(*sb, "d");
}
sbuf_cat(*sb, "j");
break;
default:
sbuf_delete(*sb);
return (EINVAL);
}
error = sbuf_finish(*sb);
if (error != 0 || sbuf_len(*sb) == 0) {
*sb = NULL;
return (error);
}
return (0);
}
static int
led_write(struct cdev *dev, struct uio *uio, int ioflag)
{
struct ledsc *sc;
char *s;
struct sbuf *sb = NULL;
int error, state = 0;
if (uio->uio_resid > 512)
return (EINVAL);
s = malloc(uio->uio_resid + 1, M_DEVBUF, M_WAITOK);
s[uio->uio_resid] = '\0';
error = uiomove(s, uio->uio_resid, uio);
if (error) {
free(s, M_DEVBUF);
return (error);
}
error = led_parse(s, &sb, &state);
free(s, M_DEVBUF);
if (error)
return (error);
mtx_lock(&led_mtx);
sc = dev->si_drv1;
if (sc != NULL)
error = led_state(sc, &sb, state);
mtx_unlock(&led_mtx);
if (sb != NULL)
sbuf_delete(sb);
return (error);
}
int
led_set(char const *name, char const *cmd)
{
struct ledsc *sc;
struct sbuf *sb = NULL;
int error, state = 0;
error = led_parse(cmd, &sb, &state);
if (error)
return (error);
mtx_lock(&led_mtx);
LIST_FOREACH(sc, &led_list, list) {
if (strcmp(sc->name, name) == 0)
break;
}
if (sc != NULL)
error = led_state(sc, &sb, state);
else
error = ENOENT;
mtx_unlock(&led_mtx);
if (sb != NULL)
sbuf_delete(sb);
return (0);
}
static struct cdevsw led_cdevsw = {
.d_version = D_VERSION,
.d_write = led_write,
.d_name = "LED",
};
struct cdev *
led_create(led_t *func, void *priv, char const *name)
{
return (led_create_state(func, priv, name, 0));
}
struct cdev *
led_create_state(led_t *func, void *priv, char const *name, int state)
{
struct ledsc *sc;
sc = malloc(sizeof *sc, M_LED, M_WAITOK | M_ZERO);
sx_xlock(&led_sx);
sc->name = strdup(name, M_LED);
sc->unit = alloc_unr(led_unit);
sc->private = priv;
sc->func = func;
sc->dev = make_dev(&led_cdevsw, sc->unit,
UID_ROOT, GID_WHEEL, 0600, "led/%s", name);
sx_xunlock(&led_sx);
mtx_lock(&led_mtx);
sc->dev->si_drv1 = sc;
if (LIST_EMPTY(&led_list))
callout_reset(&led_ch, hz / 10, led_timeout, NULL);
LIST_INSERT_HEAD(&led_list, sc, list);
sc->func(sc->private, state != 0);
mtx_unlock(&led_mtx);
return (sc->dev);
}
void
led_destroy(struct cdev *dev)
{
struct ledsc *sc;
mtx_lock(&led_mtx);
sc = dev->si_drv1;
dev->si_drv1 = NULL;
LIST_REMOVE(sc, list);
if (LIST_EMPTY(&led_list))
callout_stop(&led_ch);
mtx_unlock(&led_mtx);
sx_xlock(&led_sx);
free_unr(led_unit, sc->unit);
destroy_dev(dev);
if (sc->spec != NULL)
sbuf_delete(sc->spec);
free(sc->name, M_LED);
free(sc, M_LED);
sx_xunlock(&led_sx);
}
static void
led_drvinit(void *unused)
{
led_unit = new_unrhdr(0, INT_MAX, NULL);
mtx_init(&led_mtx, "LED mtx", NULL, MTX_DEF);
sx_init(&led_sx, "LED sx");
callout_init(&led_ch, CALLOUT_MPSAFE);
}
SYSINIT(leddev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, led_drvinit, NULL);