freebsd-dev/sys/dev/ppbus/pcfclock.c
2020-09-01 21:59:11 +00:00

338 lines
7.6 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2000 Sascha Schumann. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY SASCHA SCHUMANN ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_pcfclock.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/uio.h>
#include <machine/bus.h>
#include <machine/resource.h>
#include <dev/ppbus/ppbconf.h>
#include <dev/ppbus/ppb_msq.h>
#include <dev/ppbus/ppbio.h>
#include "ppbus_if.h"
#define PCFCLOCK_NAME "pcfclock"
struct pcfclock_data {
device_t dev;
struct cdev *cdev;
};
static devclass_t pcfclock_devclass;
static d_open_t pcfclock_open;
static d_close_t pcfclock_close;
static d_read_t pcfclock_read;
static struct cdevsw pcfclock_cdevsw = {
.d_version = D_VERSION,
.d_open = pcfclock_open,
.d_close = pcfclock_close,
.d_read = pcfclock_read,
.d_name = PCFCLOCK_NAME,
};
#ifndef PCFCLOCK_MAX_RETRIES
#define PCFCLOCK_MAX_RETRIES 10
#endif
#define AFC_HI 0
#define AFC_LO AUTOFEED
/* AUTO FEED is used as clock */
#define AUTOFEED_CLOCK(val) \
ctr = (ctr & ~(AUTOFEED)) ^ (val); ppb_wctr(ppbus, ctr)
/* SLCT is used as clock */
#define CLOCK_OK \
((ppb_rstr(ppbus) & SELECT) == (i & 1 ? SELECT : 0))
/* PE is used as data */
#define BIT_SET (ppb_rstr(ppbus)&PERROR)
/* the first byte sent as reply must be 00001001b */
#define PCFCLOCK_CORRECT_SYNC(buf) (buf[0] == 9)
#define NR(buf, off) (buf[off+1]*10+buf[off])
/* check for correct input values */
#define PCFCLOCK_CORRECT_FORMAT(buf) (\
NR(buf, 14) <= 99 && \
NR(buf, 12) <= 12 && \
NR(buf, 10) <= 31 && \
NR(buf, 6) <= 23 && \
NR(buf, 4) <= 59 && \
NR(buf, 2) <= 59)
#define PCFCLOCK_BATTERY_STATUS_LOW(buf) (buf[8] & 4)
#define PCFCLOCK_CMD_TIME 0 /* send current time */
#define PCFCLOCK_CMD_COPY 7 /* copy received signal to PC */
static void
pcfclock_identify(driver_t *driver, device_t parent)
{
device_t dev;
dev = device_find_child(parent, PCFCLOCK_NAME, -1);
if (!dev)
BUS_ADD_CHILD(parent, 0, PCFCLOCK_NAME, -1);
}
static int
pcfclock_probe(device_t dev)
{
device_set_desc(dev, "PCF-1.0");
return (0);
}
static int
pcfclock_attach(device_t dev)
{
struct pcfclock_data *sc = device_get_softc(dev);
int unit;
unit = device_get_unit(dev);
sc->dev = dev;
sc->cdev = make_dev(&pcfclock_cdevsw, unit,
UID_ROOT, GID_WHEEL, 0400, PCFCLOCK_NAME "%d", unit);
if (sc->cdev == NULL) {
device_printf(dev, "Failed to create character device\n");
return (ENXIO);
}
sc->cdev->si_drv1 = sc;
return (0);
}
static int
pcfclock_open(struct cdev *dev, int flag, int fms, struct thread *td)
{
struct pcfclock_data *sc = dev->si_drv1;
device_t pcfclockdev;
device_t ppbus;
int res;
if (!sc)
return (ENXIO);
pcfclockdev = sc->dev;
ppbus = device_get_parent(pcfclockdev);
ppb_lock(ppbus);
res = ppb_request_bus(ppbus, pcfclockdev,
(flag & O_NONBLOCK) ? PPB_DONTWAIT : PPB_WAIT);
ppb_unlock(ppbus);
return (res);
}
static int
pcfclock_close(struct cdev *dev, int flags, int fmt, struct thread *td)
{
struct pcfclock_data *sc = dev->si_drv1;
device_t pcfclockdev = sc->dev;
device_t ppbus = device_get_parent(pcfclockdev);
ppb_lock(ppbus);
ppb_release_bus(ppbus, pcfclockdev);
ppb_unlock(ppbus);
return (0);
}
static void
pcfclock_write_cmd(struct cdev *dev, unsigned char command)
{
struct pcfclock_data *sc = dev->si_drv1;
device_t pcfclockdev = sc->dev;
device_t ppbus = device_get_parent(pcfclockdev);
unsigned char ctr = 14;
char i;
for (i = 0; i <= 7; i++) {
ppb_wdtr(ppbus, i);
AUTOFEED_CLOCK(i & 1 ? AFC_HI : AFC_LO);
DELAY(3000);
}
ppb_wdtr(ppbus, command);
AUTOFEED_CLOCK(AFC_LO);
DELAY(3000);
AUTOFEED_CLOCK(AFC_HI);
}
static void
pcfclock_display_data(struct cdev *dev, char buf[18])
{
struct pcfclock_data *sc = dev->si_drv1;
#ifdef PCFCLOCK_VERBOSE
int year;
year = NR(buf, 14);
if (year < 70)
year += 100;
device_printf(sc->dev, "%02d.%02d.%4d %02d:%02d:%02d, "
"battery status: %s\n",
NR(buf, 10), NR(buf, 12), 1900 + year,
NR(buf, 6), NR(buf, 4), NR(buf, 2),
PCFCLOCK_BATTERY_STATUS_LOW(buf) ? "LOW" : "ok");
#else
if (PCFCLOCK_BATTERY_STATUS_LOW(buf))
device_printf(sc->dev, "BATTERY STATUS LOW ON\n");
#endif
}
static int
pcfclock_read_data(struct cdev *dev, char *buf, ssize_t bits)
{
struct pcfclock_data *sc = dev->si_drv1;
device_t pcfclockdev = sc->dev;
device_t ppbus = device_get_parent(pcfclockdev);
int i;
char waitfor;
int offset;
/* one byte per four bits */
bzero(buf, ((bits + 3) >> 2) + 1);
waitfor = 100;
for (i = 0; i <= bits; i++) {
/* wait for clock, maximum (waitfor*100) usec */
while (!CLOCK_OK && --waitfor > 0)
DELAY(100);
/* timed out? */
if (!waitfor)
return (EIO);
waitfor = 100; /* reload */
/* give it some time */
DELAY(500);
/* calculate offset into buffer */
offset = i >> 2;
buf[offset] <<= 1;
if (BIT_SET)
buf[offset] |= 1;
}
return (0);
}
static int
pcfclock_read_dev(struct cdev *dev, char *buf, int maxretries)
{
struct pcfclock_data *sc = dev->si_drv1;
device_t pcfclockdev = sc->dev;
device_t ppbus = device_get_parent(pcfclockdev);
int error = 0;
ppb_set_mode(ppbus, PPB_COMPATIBLE);
while (--maxretries > 0) {
pcfclock_write_cmd(dev, PCFCLOCK_CMD_TIME);
if (pcfclock_read_data(dev, buf, 68))
continue;
if (!PCFCLOCK_CORRECT_SYNC(buf))
continue;
if (!PCFCLOCK_CORRECT_FORMAT(buf))
continue;
break;
}
if (!maxretries)
error = EIO;
return (error);
}
static int
pcfclock_read(struct cdev *dev, struct uio *uio, int ioflag)
{
struct pcfclock_data *sc = dev->si_drv1;
device_t ppbus;
char buf[18];
int error = 0;
if (uio->uio_resid < 18)
return (ERANGE);
ppbus = device_get_parent(sc->dev);
ppb_lock(ppbus);
error = pcfclock_read_dev(dev, buf, PCFCLOCK_MAX_RETRIES);
ppb_unlock(ppbus);
if (error) {
device_printf(sc->dev, "no PCF found\n");
} else {
pcfclock_display_data(dev, buf);
uiomove(buf, 18, uio);
}
return (error);
}
static device_method_t pcfclock_methods[] = {
/* device interface */
DEVMETHOD(device_identify, pcfclock_identify),
DEVMETHOD(device_probe, pcfclock_probe),
DEVMETHOD(device_attach, pcfclock_attach),
{ 0, 0 }
};
static driver_t pcfclock_driver = {
PCFCLOCK_NAME,
pcfclock_methods,
sizeof(struct pcfclock_data),
};
DRIVER_MODULE(pcfclock, ppbus, pcfclock_driver, pcfclock_devclass, 0, 0);