xref: /dragonfly/sys/dev/misc/pcfclock/pcfclock.c (revision 685c703c)
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: src/sys/dev/ppbus/pcfclock.c,v 1.3.2.1 2000/05/24 00:20:57 n_hibma Exp $
25  * $DragonFly: src/sys/dev/misc/pcfclock/pcfclock.c,v 1.9 2006/07/28 02:17:36 dillon Exp $
26  *
27  */
28 
29 #include "opt_pcfclock.h"
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/bus.h>
34 #include <sys/conf.h>
35 #include <sys/device.h>
36 #include <sys/sockio.h>
37 #include <sys/mbuf.h>
38 #include <sys/kernel.h>
39 #include <sys/fcntl.h>
40 #include <sys/uio.h>
41 
42 #include <machine/bus.h>
43 #include <machine/resource.h>
44 #include <machine/clock.h>      /* for DELAY */
45 
46 #include <bus/ppbus/ppbconf.h>
47 #include <bus/ppbus/ppb_msq.h>
48 #include <bus/ppbus/ppbio.h>
49 
50 #include "ppbus_if.h"
51 
52 #define PCFCLOCK_NAME "pcfclock"
53 
54 struct pcfclock_data {
55 	int	count;
56 	struct	ppb_device pcfclock_dev;
57 };
58 
59 #define DEVTOSOFTC(dev) \
60 	((struct pcfclock_data *)device_get_softc(dev))
61 #define UNITOSOFTC(unit) \
62 	((struct pcfclock_data *)devclass_get_softc(pcfclock_devclass, (unit)))
63 #define UNITODEVICE(unit) \
64 	(devclass_get_device(pcfclock_devclass, (unit)))
65 
66 static devclass_t pcfclock_devclass;
67 
68 static	d_open_t		pcfclock_open;
69 static	d_close_t		pcfclock_close;
70 static	d_read_t		pcfclock_read;
71 
72 #define CDEV_MAJOR 140
73 static struct dev_ops pcfclock_ops = {
74 	{ PCFCLOCK_NAME, CDEV_MAJOR, 0 },
75 	.d_open =	pcfclock_open,
76 	.d_close =	pcfclock_close,
77 	.d_read =	pcfclock_read,
78 };
79 
80 #ifndef PCFCLOCK_MAX_RETRIES
81 #define PCFCLOCK_MAX_RETRIES 10
82 #endif
83 
84 #define AFC_HI 0
85 #define AFC_LO AUTOFEED
86 
87 /* AUTO FEED is used as clock */
88 #define AUTOFEED_CLOCK(val) \
89 	ctr = (ctr & ~(AUTOFEED)) ^ (val); ppb_wctr(ppbus, ctr)
90 
91 /* SLCT is used as clock */
92 #define CLOCK_OK \
93 	((ppb_rstr(ppbus) & SELECT) == (i & 1 ? SELECT : 0))
94 
95 /* PE is used as data */
96 #define BIT_SET (ppb_rstr(ppbus)&PERROR)
97 
98 /* the first byte sent as reply must be 00001001b */
99 #define PCFCLOCK_CORRECT_SYNC(buf) (buf[0] == 9)
100 
101 #define NR(buf, off) (buf[off+1]*10+buf[off])
102 
103 /* check for correct input values */
104 #define PCFCLOCK_CORRECT_FORMAT(buf) (\
105 	NR(buf, 14) <= 99 && \
106 	NR(buf, 12) <= 12 && \
107 	NR(buf, 10) <= 31 && \
108 	NR(buf,  6) <= 23 && \
109 	NR(buf,  4) <= 59 && \
110 	NR(buf,  2) <= 59)
111 
112 #define PCFCLOCK_BATTERY_STATUS_LOW(buf) (buf[8] & 4)
113 
114 #define PCFCLOCK_CMD_TIME 0		/* send current time */
115 #define PCFCLOCK_CMD_COPY 7 	/* copy received signal to PC */
116 
117 static int
118 pcfclock_probe(device_t dev)
119 {
120 	struct pcfclock_data *sc;
121 
122 	device_set_desc(dev, "PCF-1.0");
123 
124 	sc = DEVTOSOFTC(dev);
125 	bzero(sc, sizeof(struct pcfclock_data));
126 
127 	return (0);
128 }
129 
130 static int
131 pcfclock_attach(device_t dev)
132 {
133 	int unit;
134 
135 	unit = device_get_unit(dev);
136 
137 	dev_ops_add(&pcfclock_ops, -1, unit);
138 	make_dev(&pcfclock_ops, unit,
139 			UID_ROOT, GID_WHEEL, 0444, PCFCLOCK_NAME "%d", unit);
140 
141 	return (0);
142 }
143 
144 static int
145 pcfclock_open(struct dev_open_args *ap)
146 {
147 	dev_t dev = ap->a_head.a_dev;
148 	u_int unit = minor(dev);
149 	struct pcfclock_data *sc = UNITOSOFTC(unit);
150 	device_t pcfclockdev = UNITODEVICE(unit);
151 	device_t ppbus = device_get_parent(pcfclockdev);
152 	int res;
153 
154 	if (!sc)
155 		return (ENXIO);
156 
157 	if ((res = ppb_request_bus(ppbus, pcfclockdev,
158 		(ap->a_oflags & O_NONBLOCK) ? PPB_DONTWAIT : PPB_WAIT)))
159 		return (res);
160 
161 	sc->count++;
162 
163 	return (0);
164 }
165 
166 static int
167 pcfclock_close(struct dev_close_args *ap)
168 {
169 	dev_t dev = ap->a_head.a_dev;
170 	u_int unit = minor(dev);
171 	struct pcfclock_data *sc = UNITOSOFTC(unit);
172 	device_t pcfclockdev = UNITODEVICE(unit);
173 	device_t ppbus = device_get_parent(pcfclockdev);
174 
175 	sc->count--;
176 	if (sc->count == 0) {
177 		ppb_release_bus(ppbus, pcfclockdev);
178 	}
179 
180 	return (0);
181 }
182 
183 static void
184 pcfclock_write_cmd(dev_t dev, unsigned char command)
185 {
186 	u_int unit = minor(dev);
187 	device_t ppidev = UNITODEVICE(unit);
188         device_t ppbus = device_get_parent(ppidev);
189 	unsigned char ctr = 14;
190 	char i;
191 
192 	for (i = 0; i <= 7; i++) {
193 		ppb_wdtr(ppbus, i);
194 		AUTOFEED_CLOCK(i & 1 ? AFC_HI : AFC_LO);
195 		DELAY(3000);
196 	}
197 	ppb_wdtr(ppbus, command);
198 	AUTOFEED_CLOCK(AFC_LO);
199 	DELAY(3000);
200 	AUTOFEED_CLOCK(AFC_HI);
201 }
202 
203 static void
204 pcfclock_display_data(dev_t dev, char buf[18])
205 {
206 	u_int unit = minor(dev);
207 #ifdef PCFCLOCK_VERBOSE
208 	int year;
209 
210 	year = NR(buf, 14);
211 	if (year < 70)
212 		year += 100;
213 	printf(PCFCLOCK_NAME "%d: %02d.%02d.%4d %02d:%02d:%02d, "
214 			"battery status: %s\n",
215 			unit,
216 			NR(buf, 10), NR(buf, 12), 1900 + year,
217 			NR(buf, 6), NR(buf, 4), NR(buf, 2),
218 			PCFCLOCK_BATTERY_STATUS_LOW(buf) ? "LOW" : "ok");
219 #else
220 	if (PCFCLOCK_BATTERY_STATUS_LOW(buf))
221 		printf(PCFCLOCK_NAME "%d: BATTERY STATUS LOW ON\n",
222 				unit);
223 #endif
224 }
225 
226 static int
227 pcfclock_read_data(dev_t dev, char *buf, ssize_t bits)
228 {
229 	u_int unit = minor(dev);
230 	device_t ppidev = UNITODEVICE(unit);
231         device_t ppbus = device_get_parent(ppidev);
232 	int i;
233 	char waitfor;
234 	int offset;
235 
236 	/* one byte per four bits */
237 	bzero(buf, ((bits + 3) >> 2) + 1);
238 
239 	waitfor = 100;
240 	for (i = 0; i <= bits; i++) {
241 		/* wait for clock, maximum (waitfor*100) usec */
242 		while(!CLOCK_OK && --waitfor > 0)
243 			DELAY(100);
244 
245 		/* timed out? */
246 		if (!waitfor)
247 			return (EIO);
248 
249 		waitfor = 100; /* reload */
250 
251 		/* give it some time */
252 		DELAY(500);
253 
254 		/* calculate offset into buffer */
255 		offset = i >> 2;
256 		buf[offset] <<= 1;
257 
258 		if (BIT_SET)
259 			buf[offset] |= 1;
260 	}
261 
262 	return (0);
263 }
264 
265 static int
266 pcfclock_read_dev(dev_t dev, char *buf, int maxretries)
267 {
268 	u_int unit = minor(dev);
269 	device_t ppidev = UNITODEVICE(unit);
270         device_t ppbus = device_get_parent(ppidev);
271 	int error = 0;
272 
273 	ppb_set_mode(ppbus, PPB_COMPATIBLE);
274 
275 	while (--maxretries > 0) {
276 		pcfclock_write_cmd(dev, PCFCLOCK_CMD_TIME);
277 		if (pcfclock_read_data(dev, buf, 68))
278 			continue;
279 
280 		if (!PCFCLOCK_CORRECT_SYNC(buf))
281 			continue;
282 
283 		if (!PCFCLOCK_CORRECT_FORMAT(buf))
284 			continue;
285 
286 		break;
287 	}
288 
289 	if (!maxretries)
290 		error = EIO;
291 
292 	return (error);
293 }
294 
295 static int
296 pcfclock_read(struct dev_read_args *ap)
297 {
298 	dev_t dev = ap->a_head.a_dev;
299 	u_int unit = minor(dev);
300 	char buf[18];
301 	int error = 0;
302 
303 	if (ap->a_uio->uio_resid < 18)
304 		return (ERANGE);
305 
306 	error = pcfclock_read_dev(dev, buf, PCFCLOCK_MAX_RETRIES);
307 
308 	if (error) {
309 		printf(PCFCLOCK_NAME "%d: no PCF found\n", unit);
310 	} else {
311 		pcfclock_display_data(dev, buf);
312 
313 		uiomove(buf, 18, ap->a_uio);
314 	}
315 
316 	return (error);
317 }
318 
319 /*
320  * Because pcfclock is a static device that always exists under any
321  * attached ppbus, and not scanned by the ppbus, we need an identify function
322  * to create the device.
323  */
324 static device_method_t pcfclock_methods[] = {
325 	/* device interface */
326 	DEVMETHOD(device_identify,	bus_generic_identify),
327 	DEVMETHOD(device_probe,		pcfclock_probe),
328 	DEVMETHOD(device_attach,	pcfclock_attach),
329 
330 	{ 0, 0 }
331 };
332 
333 static driver_t pcfclock_driver = {
334 	PCFCLOCK_NAME,
335 	pcfclock_methods,
336 	sizeof(struct pcfclock_data),
337 };
338 
339 DRIVER_MODULE(pcfclock, ppbus, pcfclock_driver, pcfclock_devclass, 0, 0);
340 
341