pcfclock.c revision 56293 
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 REGENTS 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 * $FreeBSD: head/sys/dev/ppbus/pcfclock.c 56293 2000-01-19 18:19:16Z jkh $
25 *
26 */
27
28#include "pcfclock.h"
29
30#if NPCFCLOCK > 0
31
32#include "opt_pcfclock.h"
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/bus.h>
37#include <sys/sockio.h>
38#include <sys/mbuf.h>
39#include <sys/malloc.h>
40#include <sys/kernel.h>
41#include <sys/conf.h>
42#include <sys/fcntl.h>
43#include <sys/uio.h>
44
45#include <machine/bus.h>
46#include <machine/resource.h>
47#include <machine/clock.h>      /* for DELAY */
48
49#include <dev/ppbus/ppbconf.h>
50#include <dev/ppbus/ppb_msq.h>
51#include <dev/ppbus/ppbio.h>
52
53#include "ppbus_if.h"
54
55#define PCFCLOCK_NAME "pcfclock"
56
57struct pcfclock_data {
58	int	count;
59	struct	ppb_device pcfclock_dev;
60};
61
62#define DEVTOSOFTC(dev) \
63	((struct pcfclock_data *)device_get_softc(dev))
64#define UNITOSOFTC(unit) \
65	((struct pcfclock_data *)devclass_get_softc(pcfclock_devclass, (unit)))
66#define UNITODEVICE(unit) \
67	(devclass_get_device(pcfclock_devclass, (unit)))
68
69static devclass_t pcfclock_devclass;
70
71static int pcfclock_probe(device_t);
72static int pcfclock_attach(device_t);
73
74static device_method_t pcfclock_methods[] = {
75	/* device interface */
76	DEVMETHOD(device_probe,		pcfclock_probe),
77	DEVMETHOD(device_attach,	pcfclock_attach),
78
79	{ 0, 0 }
80};
81
82static driver_t pcfclock_driver = {
83	PCFCLOCK_NAME,
84	pcfclock_methods,
85	sizeof(struct pcfclock_data),
86};
87
88static	d_open_t		pcfclock_open;
89static	d_close_t		pcfclock_close;
90static	d_read_t		pcfclock_read;
91
92#define CDEV_MAJOR 140
93static struct cdevsw pcfclock_cdevsw = {
94	/* open */	pcfclock_open,
95	/* close */	pcfclock_close,
96	/* read */	pcfclock_read,
97	/* write */	nowrite,
98	/* ioctl */	noioctl,
99	/* poll */	nopoll,
100	/* mmap */	nommap,
101	/* strategy */	nostrategy,
102	/* name */	PCFCLOCK_NAME,
103	/* maj */	CDEV_MAJOR,
104	/* dump */	nodump,
105	/* psize */	nopsize,
106	/* flags */	0,
107	/* bmaj */	-1
108};
109
110#ifndef PCFCLOCK_MAX_RETRIES
111#define PCFCLOCK_MAX_RETRIES 10
112#endif
113
114#define AFC_HI 0
115#define AFC_LO AUTOFEED
116
117/* AUTO FEED is used as clock */
118#define AUTOFEED_CLOCK(val) \
119	ctr = (ctr & ~(AUTOFEED)) ^ (val); ppb_wctr(ppbus, ctr)
120
121/* SLCT is used as clock */
122#define CLOCK_OK \
123	((ppb_rstr(ppbus) & SELECT) == (i & 1 ? SELECT : 0))
124
125/* PE is used as data */
126#define BIT_SET (ppb_rstr(ppbus)&PERROR)
127
128/* the first byte sent as reply must be 00001001b */
129#define PCFCLOCK_CORRECT_SYNC(buf) (buf[0] == 9)
130
131#define NR(buf, off) (buf[off+1]*10+buf[off])
132
133/* check for correct input values */
134#define PCFCLOCK_CORRECT_FORMAT(buf) (\
135	NR(buf, 14) <= 99 && \
136	NR(buf, 12) <= 12 && \
137	NR(buf, 10) <= 31 && \
138	NR(buf,  6) <= 23 && \
139	NR(buf,  4) <= 59 && \
140	NR(buf,  2) <= 59)
141
142#define PCFCLOCK_BATTERY_STATUS_LOW(buf) (buf[8] & 4)
143
144#define PCFCLOCK_CMD_TIME 0		/* send current time */
145#define PCFCLOCK_CMD_COPY 7 	/* copy received signal to PC */
146
147static int
148pcfclock_probe(device_t dev)
149{
150	struct pcfclock_data *sc;
151	static int once;
152
153	device_set_desc(dev, "PCF-1.0");
154
155	if (!once++)
156		cdevsw_add(&pcfclock_cdevsw);
157
158	sc = DEVTOSOFTC(dev);
159	bzero(sc, sizeof(struct pcfclock_data));
160
161	return (0);
162}
163
164static int
165pcfclock_attach(device_t dev)
166{
167	int unit;
168
169	unit = device_get_unit(dev);
170
171	make_dev(&pcfclock_cdevsw, unit,
172			UID_ROOT, GID_WHEEL, 0444, PCFCLOCK_NAME "%d", unit);
173
174	return (0);
175}
176
177static int
178pcfclock_open(dev_t dev, int flag, int fms, struct proc *p)
179{
180	u_int unit = minor(dev);
181	struct pcfclock_data *sc = UNITOSOFTC(unit);
182	device_t pcfclockdev = UNITODEVICE(unit);
183	device_t ppbus = device_get_parent(pcfclockdev);
184	int res;
185
186	if (!sc)
187		return (ENXIO);
188
189	if ((res = ppb_request_bus(ppbus, pcfclockdev,
190		(flag & O_NONBLOCK) ? PPB_DONTWAIT : PPB_WAIT)))
191		return (res);
192
193	sc->count++;
194
195	return (0);
196}
197
198static int
199pcfclock_close(dev_t dev, int flags, int fmt, struct proc *p)
200{
201	u_int unit = minor(dev);
202	struct pcfclock_data *sc = UNITOSOFTC(unit);
203	device_t pcfclockdev = UNITODEVICE(unit);
204	device_t ppbus = device_get_parent(pcfclockdev);
205
206	sc->count--;
207	if (sc->count == 0) {
208		ppb_release_bus(ppbus, pcfclockdev);
209	}
210
211	return (0);
212}
213
214static void
215pcfclock_write_cmd(dev_t dev, unsigned char command)
216{
217	u_int unit = minor(dev);
218	device_t ppidev = UNITODEVICE(unit);
219        device_t ppbus = device_get_parent(ppidev);
220	unsigned char ctr = 14;
221	char i;
222
223	for (i = 0; i <= 7; i++) {
224		ppb_wdtr(ppbus, i);
225		AUTOFEED_CLOCK(i & 1 ? AFC_HI : AFC_LO);
226		DELAY(3000);
227	}
228	ppb_wdtr(ppbus, command);
229	AUTOFEED_CLOCK(AFC_LO);
230	DELAY(3000);
231	AUTOFEED_CLOCK(AFC_HI);
232}
233
234static void
235pcfclock_display_data(dev_t dev, char buf[18])
236{
237	u_int unit = minor(dev);
238#ifdef PCFCLOCK_VERBOSE
239	int year;
240
241	year = NR(buf, 14);
242	if (year < 70)
243		year += 100;
244	printf(PCFCLOCK_NAME "%d: %02d.%02d.%4d %02d:%02d:%02d, "
245			"battery status: %s\n",
246			unit,
247			NR(buf, 10), NR(buf, 12), 1900 + year,
248			NR(buf, 6), NR(buf, 4), NR(buf, 2),
249			PCFCLOCK_BATTERY_STATUS_LOW(buf) ? "LOW" : "ok");
250#else
251	if (PCFCLOCK_BATTERY_STATUS_LOW(buf))
252		printf(PCFCLOCK_NAME "%d: BATTERY STATUS LOW ON\n",
253				unit);
254#endif
255}
256
257static int
258pcfclock_read_data(dev_t dev, char *buf, ssize_t bits)
259{
260	u_int unit = minor(dev);
261	device_t ppidev = UNITODEVICE(unit);
262        device_t ppbus = device_get_parent(ppidev);
263	int i;
264	char waitfor;
265	int offset;
266
267	/* one byte per four bits */
268	bzero(buf, ((bits + 3) >> 2) + 1);
269
270	waitfor = 100;
271	for (i = 0; i <= bits; i++) {
272		/* wait for clock, maximum (waitfor*100) usec */
273		while(!CLOCK_OK && --waitfor > 0)
274			DELAY(100);
275
276		/* timed out? */
277		if (!waitfor)
278			return (EIO);
279
280		waitfor = 100; /* reload */
281
282		/* give it some time */
283		DELAY(500);
284
285		/* calculate offset into buffer */
286		offset = i >> 2;
287		buf[offset] <<= 1;
288
289		if (BIT_SET)
290			buf[offset] |= 1;
291	}
292
293	return (0);
294}
295
296static int
297pcfclock_read_dev(dev_t dev, char *buf, int maxretries)
298{
299	u_int unit = minor(dev);
300	device_t ppidev = UNITODEVICE(unit);
301        device_t ppbus = device_get_parent(ppidev);
302	int error = 0;
303
304	ppb_set_mode(ppbus, PPB_COMPATIBLE);
305
306	while (--maxretries > 0) {
307		pcfclock_write_cmd(dev, PCFCLOCK_CMD_TIME);
308		if (pcfclock_read_data(dev, buf, 68))
309			continue;
310
311		if (!PCFCLOCK_CORRECT_SYNC(buf))
312			continue;
313
314		if (!PCFCLOCK_CORRECT_FORMAT(buf))
315			continue;
316
317		break;
318	}
319
320	if (!maxretries)
321		error = EIO;
322
323	return (error);
324}
325
326static ssize_t
327pcfclock_read(dev_t dev, struct uio *uio, int ioflag)
328{
329	u_int unit = minor(dev);
330	char buf[18];
331	int error = 0;
332
333	error = pcfclock_read_dev(dev, buf, PCFCLOCK_MAX_RETRIES);
334
335	if (error) {
336		printf(PCFCLOCK_NAME "%d: no PCF found\n", unit);
337	} else {
338		pcfclock_display_data(dev, buf);
339
340		uiomove(buf, 18, uio);
341	}
342
343	return (error);
344}
345
346DRIVER_MODULE(pcfclock, ppbus, pcfclock_driver, pcfclock_devclass, 0, 0);
347
348#endif /* NPCFCLOCK */
349