xref: /dragonfly/sys/dev/misc/pcfclock/pcfclock.c (revision 6b5c5d0d)
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 1.12 2006/12/22 23:26:18 swildner 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/clock.h>      /* for DELAY */
43 
44 #include <bus/ppbus/ppbconf.h>
45 #include <bus/ppbus/ppb_msq.h>
46 #include <bus/ppbus/ppbio.h>
47 
48 #include "ppbus_if.h"
49 
50 #define PCFCLOCK_NAME "pcfclock"
51 
52 struct pcfclock_data {
53 	int	count;
54 	struct	ppb_device pcfclock_dev;
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 
64 static devclass_t pcfclock_devclass;
65 
66 static	d_open_t		pcfclock_open;
67 static	d_close_t		pcfclock_close;
68 static	d_read_t		pcfclock_read;
69 
70 #define CDEV_MAJOR 140
71 static struct dev_ops pcfclock_ops = {
72 	{ PCFCLOCK_NAME, CDEV_MAJOR, 0 },
73 	.d_open =	pcfclock_open,
74 	.d_close =	pcfclock_close,
75 	.d_read =	pcfclock_read,
76 };
77 
78 #ifndef PCFCLOCK_MAX_RETRIES
79 #define PCFCLOCK_MAX_RETRIES 10
80 #endif
81 
82 #define AFC_HI 0
83 #define AFC_LO AUTOFEED
84 
85 /* AUTO FEED is used as clock */
86 #define AUTOFEED_CLOCK(val) \
87 	ctr = (ctr & ~(AUTOFEED)) ^ (val); ppb_wctr(ppbus, ctr)
88 
89 /* SLCT is used as clock */
90 #define CLOCK_OK \
91 	((ppb_rstr(ppbus) & SELECT) == (i & 1 ? SELECT : 0))
92 
93 /* PE is used as data */
94 #define BIT_SET (ppb_rstr(ppbus)&PERROR)
95 
96 /* the first byte sent as reply must be 00001001b */
97 #define PCFCLOCK_CORRECT_SYNC(buf) (buf[0] == 9)
98 
99 #define NR(buf, off) (buf[off+1]*10+buf[off])
100 
101 /* check for correct input values */
102 #define PCFCLOCK_CORRECT_FORMAT(buf) (\
103 	NR(buf, 14) <= 99 && \
104 	NR(buf, 12) <= 12 && \
105 	NR(buf, 10) <= 31 && \
106 	NR(buf,  6) <= 23 && \
107 	NR(buf,  4) <= 59 && \
108 	NR(buf,  2) <= 59)
109 
110 #define PCFCLOCK_BATTERY_STATUS_LOW(buf) (buf[8] & 4)
111 
112 #define PCFCLOCK_CMD_TIME 0		/* send current time */
113 #define PCFCLOCK_CMD_COPY 7 	/* copy received signal to PC */
114 
115 static int
116 pcfclock_probe(device_t dev)
117 {
118 	struct pcfclock_data *sc;
119 
120 	device_set_desc(dev, "PCF-1.0");
121 
122 	sc = DEVTOSOFTC(dev);
123 	bzero(sc, sizeof(struct pcfclock_data));
124 
125 	return (0);
126 }
127 
128 static int
129 pcfclock_attach(device_t dev)
130 {
131 	int unit;
132 
133 	unit = device_get_unit(dev);
134 
135 	dev_ops_add(&pcfclock_ops, -1, unit);
136 	make_dev(&pcfclock_ops, unit,
137 			UID_ROOT, GID_WHEEL, 0444, PCFCLOCK_NAME "%d", unit);
138 
139 	return (0);
140 }
141 
142 static int
143 pcfclock_open(struct dev_open_args *ap)
144 {
145 	cdev_t dev = ap->a_head.a_dev;
146 	u_int unit = minor(dev);
147 	struct pcfclock_data *sc = UNITOSOFTC(unit);
148 	device_t pcfclockdev = UNITODEVICE(unit);
149 	device_t ppbus = device_get_parent(pcfclockdev);
150 	int res;
151 
152 	if (!sc)
153 		return (ENXIO);
154 
155 	if ((res = ppb_request_bus(ppbus, pcfclockdev,
156 		(ap->a_oflags & O_NONBLOCK) ? PPB_DONTWAIT : PPB_WAIT)))
157 		return (res);
158 
159 	sc->count++;
160 
161 	return (0);
162 }
163 
164 static int
165 pcfclock_close(struct dev_close_args *ap)
166 {
167 	cdev_t dev = ap->a_head.a_dev;
168 	u_int unit = minor(dev);
169 	struct pcfclock_data *sc = UNITOSOFTC(unit);
170 	device_t pcfclockdev = UNITODEVICE(unit);
171 	device_t ppbus = device_get_parent(pcfclockdev);
172 
173 	sc->count--;
174 	if (sc->count == 0) {
175 		ppb_release_bus(ppbus, pcfclockdev);
176 	}
177 
178 	return (0);
179 }
180 
181 static void
182 pcfclock_write_cmd(cdev_t dev, unsigned char command)
183 {
184 	u_int unit = minor(dev);
185 	device_t ppidev = UNITODEVICE(unit);
186         device_t ppbus = device_get_parent(ppidev);
187 	unsigned char ctr = 14;
188 	char i;
189 
190 	for (i = 0; i <= 7; i++) {
191 		ppb_wdtr(ppbus, i);
192 		AUTOFEED_CLOCK(i & 1 ? AFC_HI : AFC_LO);
193 		DELAY(3000);
194 	}
195 	ppb_wdtr(ppbus, command);
196 	AUTOFEED_CLOCK(AFC_LO);
197 	DELAY(3000);
198 	AUTOFEED_CLOCK(AFC_HI);
199 }
200 
201 static void
202 pcfclock_display_data(cdev_t dev, char buf[18])
203 {
204 	u_int unit = minor(dev);
205 #ifdef PCFCLOCK_VERBOSE
206 	int year;
207 
208 	year = NR(buf, 14);
209 	if (year < 70)
210 		year += 100;
211 	kprintf(PCFCLOCK_NAME "%d: %02d.%02d.%4d %02d:%02d:%02d, "
212 			"battery status: %s\n",
213 			unit,
214 			NR(buf, 10), NR(buf, 12), 1900 + year,
215 			NR(buf, 6), NR(buf, 4), NR(buf, 2),
216 			PCFCLOCK_BATTERY_STATUS_LOW(buf) ? "LOW" : "ok");
217 #else
218 	if (PCFCLOCK_BATTERY_STATUS_LOW(buf))
219 		kprintf(PCFCLOCK_NAME "%d: BATTERY STATUS LOW ON\n",
220 				unit);
221 #endif
222 }
223 
224 static int
225 pcfclock_read_data(cdev_t dev, char *buf, ssize_t bits)
226 {
227 	u_int unit = minor(dev);
228 	device_t ppidev = UNITODEVICE(unit);
229         device_t ppbus = device_get_parent(ppidev);
230 	int i;
231 	char waitfor;
232 	int offset;
233 
234 	/* one byte per four bits */
235 	bzero(buf, ((bits + 3) >> 2) + 1);
236 
237 	waitfor = 100;
238 	for (i = 0; i <= bits; i++) {
239 		/* wait for clock, maximum (waitfor*100) usec */
240 		while(!CLOCK_OK && --waitfor > 0)
241 			DELAY(100);
242 
243 		/* timed out? */
244 		if (!waitfor)
245 			return (EIO);
246 
247 		waitfor = 100; /* reload */
248 
249 		/* give it some time */
250 		DELAY(500);
251 
252 		/* calculate offset into buffer */
253 		offset = i >> 2;
254 		buf[offset] <<= 1;
255 
256 		if (BIT_SET)
257 			buf[offset] |= 1;
258 	}
259 
260 	return (0);
261 }
262 
263 static int
264 pcfclock_read_dev(cdev_t dev, char *buf, int maxretries)
265 {
266 	u_int unit = minor(dev);
267 	device_t ppidev = UNITODEVICE(unit);
268         device_t ppbus = device_get_parent(ppidev);
269 	int error = 0;
270 
271 	ppb_set_mode(ppbus, PPB_COMPATIBLE);
272 
273 	while (--maxretries > 0) {
274 		pcfclock_write_cmd(dev, PCFCLOCK_CMD_TIME);
275 		if (pcfclock_read_data(dev, buf, 68))
276 			continue;
277 
278 		if (!PCFCLOCK_CORRECT_SYNC(buf))
279 			continue;
280 
281 		if (!PCFCLOCK_CORRECT_FORMAT(buf))
282 			continue;
283 
284 		break;
285 	}
286 
287 	if (!maxretries)
288 		error = EIO;
289 
290 	return (error);
291 }
292 
293 static int
294 pcfclock_read(struct dev_read_args *ap)
295 {
296 	cdev_t dev = ap->a_head.a_dev;
297 	u_int unit = minor(dev);
298 	char buf[18];
299 	int error = 0;
300 
301 	if (ap->a_uio->uio_resid < 18)
302 		return (ERANGE);
303 
304 	error = pcfclock_read_dev(dev, buf, PCFCLOCK_MAX_RETRIES);
305 
306 	if (error) {
307 		kprintf(PCFCLOCK_NAME "%d: no PCF found\n", unit);
308 	} else {
309 		pcfclock_display_data(dev, buf);
310 
311 		uiomove(buf, 18, ap->a_uio);
312 	}
313 
314 	return (error);
315 }
316 
317 /*
318  * Because pcfclock is a static device that always exists under any
319  * attached ppbus, and not scanned by the ppbus, we need an identify function
320  * to create the device.
321  */
322 static device_method_t pcfclock_methods[] = {
323 	/* device interface */
324 	DEVMETHOD(device_identify,	bus_generic_identify),
325 	DEVMETHOD(device_probe,		pcfclock_probe),
326 	DEVMETHOD(device_attach,	pcfclock_attach),
327 
328 	{ 0, 0 }
329 };
330 
331 static driver_t pcfclock_driver = {
332 	PCFCLOCK_NAME,
333 	pcfclock_methods,
334 	sizeof(struct pcfclock_data),
335 };
336 
337 DRIVER_MODULE(pcfclock, ppbus, pcfclock_driver, pcfclock_devclass, 0, 0);
338 
339