pcfclock.c revision 119418 
1/*
2 * Copyright (c) 2000 Sascha Schumann. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY SASCHA SCHUMANN ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
15 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
16 * EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
18 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
19 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
20 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
21 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
22 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 *
24 *
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/dev/ppbus/pcfclock.c 119418 2003-08-24 17:55:58Z obrien $");
29
30#include "opt_pcfclock.h"
31
32#include <sys/param.h>
33#include <sys/systm.h>
34#include <sys/bus.h>
35#include <sys/sockio.h>
36#include <sys/mbuf.h>
37#include <sys/kernel.h>
38#include <sys/conf.h>
39#include <sys/fcntl.h>
40#include <sys/uio.h>
41
42#include <machine/bus.h>
43#include <machine/resource.h>
44
45#include <dev/ppbus/ppbconf.h>
46#include <dev/ppbus/ppb_msq.h>
47#include <dev/ppbus/ppbio.h>
48
49#include "ppbus_if.h"
50
51#define PCFCLOCK_NAME "pcfclock"
52
53struct pcfclock_data {
54	int	count;
55};
56
57#define DEVTOSOFTC(dev) \
58	((struct pcfclock_data *)device_get_softc(dev))
59#define UNITOSOFTC(unit) \
60	((struct pcfclock_data *)devclass_get_softc(pcfclock_devclass, (unit)))
61#define UNITODEVICE(unit) \
62	(devclass_get_device(pcfclock_devclass, (unit)))
63
64static devclass_t pcfclock_devclass;
65
66static	d_open_t		pcfclock_open;
67static	d_close_t		pcfclock_close;
68static	d_read_t		pcfclock_read;
69
70#define CDEV_MAJOR 140
71static struct cdevsw pcfclock_cdevsw = {
72	.d_open =	pcfclock_open,
73	.d_close =	pcfclock_close,
74	.d_read =	pcfclock_read,
75	.d_name =	PCFCLOCK_NAME,
76	.d_maj =	CDEV_MAJOR,
77};
78
79#ifndef PCFCLOCK_MAX_RETRIES
80#define PCFCLOCK_MAX_RETRIES 10
81#endif
82
83#define AFC_HI 0
84#define AFC_LO AUTOFEED
85
86/* AUTO FEED is used as clock */
87#define AUTOFEED_CLOCK(val) \
88	ctr = (ctr & ~(AUTOFEED)) ^ (val); ppb_wctr(ppbus, ctr)
89
90/* SLCT is used as clock */
91#define CLOCK_OK \
92	((ppb_rstr(ppbus) & SELECT) == (i & 1 ? SELECT : 0))
93
94/* PE is used as data */
95#define BIT_SET (ppb_rstr(ppbus)&PERROR)
96
97/* the first byte sent as reply must be 00001001b */
98#define PCFCLOCK_CORRECT_SYNC(buf) (buf[0] == 9)
99
100#define NR(buf, off) (buf[off+1]*10+buf[off])
101
102/* check for correct input values */
103#define PCFCLOCK_CORRECT_FORMAT(buf) (\
104	NR(buf, 14) <= 99 && \
105	NR(buf, 12) <= 12 && \
106	NR(buf, 10) <= 31 && \
107	NR(buf,  6) <= 23 && \
108	NR(buf,  4) <= 59 && \
109	NR(buf,  2) <= 59)
110
111#define PCFCLOCK_BATTERY_STATUS_LOW(buf) (buf[8] & 4)
112
113#define PCFCLOCK_CMD_TIME 0		/* send current time */
114#define PCFCLOCK_CMD_COPY 7 	/* copy received signal to PC */
115
116static void
117pcfclock_identify(driver_t *driver, device_t parent)
118{
119
120	BUS_ADD_CHILD(parent, 0, PCFCLOCK_NAME, -1);
121}
122
123static int
124pcfclock_probe(device_t dev)
125{
126	struct pcfclock_data *sc;
127
128	device_set_desc(dev, "PCF-1.0");
129
130	sc = DEVTOSOFTC(dev);
131	bzero(sc, sizeof(struct pcfclock_data));
132
133	return (0);
134}
135
136static int
137pcfclock_attach(device_t dev)
138{
139	int unit;
140
141	unit = device_get_unit(dev);
142
143	make_dev(&pcfclock_cdevsw, unit,
144			UID_ROOT, GID_WHEEL, 0400, PCFCLOCK_NAME "%d", unit);
145
146	return (0);
147}
148
149static int
150pcfclock_open(dev_t dev, int flag, int fms, struct thread *td)
151{
152	u_int unit = minor(dev);
153	struct pcfclock_data *sc = UNITOSOFTC(unit);
154	device_t pcfclockdev = UNITODEVICE(unit);
155	device_t ppbus = device_get_parent(pcfclockdev);
156	int res;
157
158	if (!sc)
159		return (ENXIO);
160
161	if ((res = ppb_request_bus(ppbus, pcfclockdev,
162		(flag & O_NONBLOCK) ? PPB_DONTWAIT : PPB_WAIT)))
163		return (res);
164
165	sc->count++;
166
167	return (0);
168}
169
170static int
171pcfclock_close(dev_t dev, int flags, int fmt, struct thread *td)
172{
173	u_int unit = minor(dev);
174	struct pcfclock_data *sc = UNITOSOFTC(unit);
175	device_t pcfclockdev = UNITODEVICE(unit);
176	device_t ppbus = device_get_parent(pcfclockdev);
177
178	sc->count--;
179	if (sc->count == 0)
180		ppb_release_bus(ppbus, pcfclockdev);
181
182	return (0);
183}
184
185static void
186pcfclock_write_cmd(dev_t dev, unsigned char command)
187{
188	u_int unit = minor(dev);
189	device_t ppidev = UNITODEVICE(unit);
190        device_t ppbus = device_get_parent(ppidev);
191	unsigned char ctr = 14;
192	char i;
193
194	for (i = 0; i <= 7; i++) {
195		ppb_wdtr(ppbus, i);
196		AUTOFEED_CLOCK(i & 1 ? AFC_HI : AFC_LO);
197		DELAY(3000);
198	}
199	ppb_wdtr(ppbus, command);
200	AUTOFEED_CLOCK(AFC_LO);
201	DELAY(3000);
202	AUTOFEED_CLOCK(AFC_HI);
203}
204
205static void
206pcfclock_display_data(dev_t dev, char buf[18])
207{
208	u_int unit = minor(dev);
209#ifdef PCFCLOCK_VERBOSE
210	int year;
211
212	year = NR(buf, 14);
213	if (year < 70)
214		year += 100;
215
216	printf(PCFCLOCK_NAME "%d: %02d.%02d.%4d %02d:%02d:%02d, "
217			"battery status: %s\n",
218			unit,
219			NR(buf, 10), NR(buf, 12), 1900 + year,
220			NR(buf, 6), NR(buf, 4), NR(buf, 2),
221			PCFCLOCK_BATTERY_STATUS_LOW(buf) ? "LOW" : "ok");
222#else
223	if (PCFCLOCK_BATTERY_STATUS_LOW(buf))
224		printf(PCFCLOCK_NAME "%d: BATTERY STATUS LOW ON\n",
225				unit);
226#endif
227}
228
229static int
230pcfclock_read_data(dev_t dev, char *buf, ssize_t bits)
231{
232	u_int unit = minor(dev);
233	device_t ppidev = UNITODEVICE(unit);
234        device_t ppbus = device_get_parent(ppidev);
235	int i;
236	char waitfor;
237	int offset;
238
239	/* one byte per four bits */
240	bzero(buf, ((bits + 3) >> 2) + 1);
241
242	waitfor = 100;
243	for (i = 0; i <= bits; i++) {
244		/* wait for clock, maximum (waitfor*100) usec */
245		while(!CLOCK_OK && --waitfor > 0)
246			DELAY(100);
247
248		/* timed out? */
249		if (!waitfor)
250			return (EIO);
251
252		waitfor = 100; /* reload */
253
254		/* give it some time */
255		DELAY(500);
256
257		/* calculate offset into buffer */
258		offset = i >> 2;
259		buf[offset] <<= 1;
260
261		if (BIT_SET)
262			buf[offset] |= 1;
263	}
264
265	return (0);
266}
267
268static int
269pcfclock_read_dev(dev_t dev, char *buf, int maxretries)
270{
271	u_int unit = minor(dev);
272	device_t ppidev = UNITODEVICE(unit);
273        device_t ppbus = device_get_parent(ppidev);
274	int error = 0;
275
276	ppb_set_mode(ppbus, PPB_COMPATIBLE);
277
278	while (--maxretries > 0) {
279		pcfclock_write_cmd(dev, PCFCLOCK_CMD_TIME);
280		if (pcfclock_read_data(dev, buf, 68))
281			continue;
282
283		if (!PCFCLOCK_CORRECT_SYNC(buf))
284			continue;
285
286		if (!PCFCLOCK_CORRECT_FORMAT(buf))
287			continue;
288
289		break;
290	}
291
292	if (!maxretries)
293		error = EIO;
294
295	return (error);
296}
297
298static int
299pcfclock_read(dev_t dev, struct uio *uio, int ioflag)
300{
301	u_int unit = minor(dev);
302	char buf[18];
303	int error = 0;
304
305	if (uio->uio_resid < 18)
306		return (ERANGE);
307
308	error = pcfclock_read_dev(dev, buf, PCFCLOCK_MAX_RETRIES);
309
310	if (error) {
311		printf(PCFCLOCK_NAME "%d: no PCF found\n", unit);
312	} else {
313		pcfclock_display_data(dev, buf);
314
315		uiomove(buf, 18, uio);
316	}
317
318	return (error);
319}
320
321static device_method_t pcfclock_methods[] = {
322	/* device interface */
323	DEVMETHOD(device_identify,	pcfclock_identify),
324	DEVMETHOD(device_probe,		pcfclock_probe),
325	DEVMETHOD(device_attach,	pcfclock_attach),
326
327	{ 0, 0 }
328};
329
330static driver_t pcfclock_driver = {
331	PCFCLOCK_NAME,
332	pcfclock_methods,
333	sizeof(struct pcfclock_data),
334};
335
336DRIVER_MODULE(pcfclock, ppbus, pcfclock_driver, pcfclock_devclass, 0, 0);
337