1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2000 Sascha Schumann. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY SASCHA SCHUMANN ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
17 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
18 * EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
20 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
21 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
22 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
23 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
24 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 *
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
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/kernel.h>
40 #include <sys/module.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
48 #include <dev/ppbus/ppbconf.h>
49 #include <dev/ppbus/ppb_msq.h>
50 #include <dev/ppbus/ppbio.h>
51
52 #include "ppbus_if.h"
53
54 #define PCFCLOCK_NAME "pcfclock"
55
56 struct pcfclock_data {
57 device_t dev;
58 struct cdev *cdev;
59 };
60
61 static devclass_t pcfclock_devclass;
62
63 static d_open_t pcfclock_open;
64 static d_close_t pcfclock_close;
65 static d_read_t pcfclock_read;
66
67 static struct cdevsw pcfclock_cdevsw = {
68 .d_version = D_VERSION,
69 .d_open = pcfclock_open,
70 .d_close = pcfclock_close,
71 .d_read = pcfclock_read,
72 .d_name = PCFCLOCK_NAME,
73 };
74
75 #ifndef PCFCLOCK_MAX_RETRIES
76 #define PCFCLOCK_MAX_RETRIES 10
77 #endif
78
79 #define AFC_HI 0
80 #define AFC_LO AUTOFEED
81
82 /* AUTO FEED is used as clock */
83 #define AUTOFEED_CLOCK(val) \
84 ctr = (ctr & ~(AUTOFEED)) ^ (val); ppb_wctr(ppbus, ctr)
85
86 /* SLCT is used as clock */
87 #define CLOCK_OK \
88 ((ppb_rstr(ppbus) & SELECT) == (i & 1 ? SELECT : 0))
89
90 /* PE is used as data */
91 #define BIT_SET (ppb_rstr(ppbus)&PERROR)
92
93 /* the first byte sent as reply must be 00001001b */
94 #define PCFCLOCK_CORRECT_SYNC(buf) (buf[0] == 9)
95
96 #define NR(buf, off) (buf[off+1]*10+buf[off])
97
98 /* check for correct input values */
99 #define PCFCLOCK_CORRECT_FORMAT(buf) (\
100 NR(buf, 14) <= 99 && \
101 NR(buf, 12) <= 12 && \
102 NR(buf, 10) <= 31 && \
103 NR(buf, 6) <= 23 && \
104 NR(buf, 4) <= 59 && \
105 NR(buf, 2) <= 59)
106
107 #define PCFCLOCK_BATTERY_STATUS_LOW(buf) (buf[8] & 4)
108
109 #define PCFCLOCK_CMD_TIME 0 /* send current time */
110 #define PCFCLOCK_CMD_COPY 7 /* copy received signal to PC */
111
112 static void
pcfclock_identify(driver_t * driver,device_t parent)113 pcfclock_identify(driver_t *driver, device_t parent)
114 {
115
116 device_t dev;
117
118 dev = device_find_child(parent, PCFCLOCK_NAME, -1);
119 if (!dev)
120 BUS_ADD_CHILD(parent, 0, PCFCLOCK_NAME, -1);
121 }
122
123 static int
pcfclock_probe(device_t dev)124 pcfclock_probe(device_t dev)
125 {
126
127 device_set_desc(dev, "PCF-1.0");
128 return (0);
129 }
130
131 static int
pcfclock_attach(device_t dev)132 pcfclock_attach(device_t dev)
133 {
134 struct pcfclock_data *sc = device_get_softc(dev);
135 int unit;
136
137 unit = device_get_unit(dev);
138
139 sc->dev = dev;
140 sc->cdev = make_dev(&pcfclock_cdevsw, unit,
141 UID_ROOT, GID_WHEEL, 0400, PCFCLOCK_NAME "%d", unit);
142 if (sc->cdev == NULL) {
143 device_printf(dev, "Failed to create character device\n");
144 return (ENXIO);
145 }
146 sc->cdev->si_drv1 = sc;
147
148 return (0);
149 }
150
151 static int
pcfclock_open(struct cdev * dev,int flag,int fms,struct thread * td)152 pcfclock_open(struct cdev *dev, int flag, int fms, struct thread *td)
153 {
154 struct pcfclock_data *sc = dev->si_drv1;
155 device_t pcfclockdev;
156 device_t ppbus;
157 int res;
158
159 if (!sc)
160 return (ENXIO);
161 pcfclockdev = sc->dev;
162 ppbus = device_get_parent(pcfclockdev);
163
164 ppb_lock(ppbus);
165 res = ppb_request_bus(ppbus, pcfclockdev,
166 (flag & O_NONBLOCK) ? PPB_DONTWAIT : PPB_WAIT);
167 ppb_unlock(ppbus);
168 return (res);
169 }
170
171 static int
pcfclock_close(struct cdev * dev,int flags,int fmt,struct thread * td)172 pcfclock_close(struct cdev *dev, int flags, int fmt, struct thread *td)
173 {
174 struct pcfclock_data *sc = dev->si_drv1;
175 device_t pcfclockdev = sc->dev;
176 device_t ppbus = device_get_parent(pcfclockdev);
177
178 ppb_lock(ppbus);
179 ppb_release_bus(ppbus, pcfclockdev);
180 ppb_unlock(ppbus);
181
182 return (0);
183 }
184
185 static void
pcfclock_write_cmd(struct cdev * dev,unsigned char command)186 pcfclock_write_cmd(struct cdev *dev, unsigned char command)
187 {
188 struct pcfclock_data *sc = dev->si_drv1;
189 device_t pcfclockdev = sc->dev;
190 device_t ppbus = device_get_parent(pcfclockdev);
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
205 static void
pcfclock_display_data(struct cdev * dev,char buf[18])206 pcfclock_display_data(struct cdev *dev, char buf[18])
207 {
208 struct pcfclock_data *sc = dev->si_drv1;
209 #ifdef PCFCLOCK_VERBOSE
210 int year;
211
212 year = NR(buf, 14);
213 if (year < 70)
214 year += 100;
215
216 device_printf(sc->dev, "%02d.%02d.%4d %02d:%02d:%02d, "
217 "battery status: %s\n",
218 NR(buf, 10), NR(buf, 12), 1900 + year,
219 NR(buf, 6), NR(buf, 4), NR(buf, 2),
220 PCFCLOCK_BATTERY_STATUS_LOW(buf) ? "LOW" : "ok");
221 #else
222 if (PCFCLOCK_BATTERY_STATUS_LOW(buf))
223 device_printf(sc->dev, "BATTERY STATUS LOW ON\n");
224 #endif
225 }
226
227 static int
pcfclock_read_data(struct cdev * dev,char * buf,ssize_t bits)228 pcfclock_read_data(struct cdev *dev, char *buf, ssize_t bits)
229 {
230 struct pcfclock_data *sc = dev->si_drv1;
231 device_t pcfclockdev = sc->dev;
232 device_t ppbus = device_get_parent(pcfclockdev);
233 int i;
234 char waitfor;
235 int offset;
236
237 /* one byte per four bits */
238 bzero(buf, ((bits + 3) >> 2) + 1);
239
240 waitfor = 100;
241 for (i = 0; i <= bits; i++) {
242 /* wait for clock, maximum (waitfor*100) usec */
243 while (!CLOCK_OK && --waitfor > 0)
244 DELAY(100);
245
246 /* timed out? */
247 if (!waitfor)
248 return (EIO);
249
250 waitfor = 100; /* reload */
251
252 /* give it some time */
253 DELAY(500);
254
255 /* calculate offset into buffer */
256 offset = i >> 2;
257 buf[offset] <<= 1;
258
259 if (BIT_SET)
260 buf[offset] |= 1;
261 }
262
263 return (0);
264 }
265
266 static int
pcfclock_read_dev(struct cdev * dev,char * buf,int maxretries)267 pcfclock_read_dev(struct cdev *dev, char *buf, int maxretries)
268 {
269 struct pcfclock_data *sc = dev->si_drv1;
270 device_t pcfclockdev = sc->dev;
271 device_t ppbus = device_get_parent(pcfclockdev);
272 int error = 0;
273
274 ppb_set_mode(ppbus, PPB_COMPATIBLE);
275
276 while (--maxretries > 0) {
277 pcfclock_write_cmd(dev, PCFCLOCK_CMD_TIME);
278 if (pcfclock_read_data(dev, buf, 68))
279 continue;
280
281 if (!PCFCLOCK_CORRECT_SYNC(buf))
282 continue;
283
284 if (!PCFCLOCK_CORRECT_FORMAT(buf))
285 continue;
286
287 break;
288 }
289
290 if (!maxretries)
291 error = EIO;
292
293 return (error);
294 }
295
296 static int
pcfclock_read(struct cdev * dev,struct uio * uio,int ioflag)297 pcfclock_read(struct cdev *dev, struct uio *uio, int ioflag)
298 {
299 struct pcfclock_data *sc = dev->si_drv1;
300 device_t ppbus;
301 char buf[18];
302 int error = 0;
303
304 if (uio->uio_resid < 18)
305 return (ERANGE);
306
307 ppbus = device_get_parent(sc->dev);
308 ppb_lock(ppbus);
309 error = pcfclock_read_dev(dev, buf, PCFCLOCK_MAX_RETRIES);
310 ppb_unlock(ppbus);
311
312 if (error) {
313 device_printf(sc->dev, "no PCF found\n");
314 } else {
315 pcfclock_display_data(dev, buf);
316
317 uiomove(buf, 18, uio);
318 }
319
320 return (error);
321 }
322
323 static device_method_t pcfclock_methods[] = {
324 /* device interface */
325 DEVMETHOD(device_identify, pcfclock_identify),
326 DEVMETHOD(device_probe, pcfclock_probe),
327 DEVMETHOD(device_attach, pcfclock_attach),
328
329 { 0, 0 }
330 };
331
332 static driver_t pcfclock_driver = {
333 PCFCLOCK_NAME,
334 pcfclock_methods,
335 sizeof(struct pcfclock_data),
336 };
337
338 DRIVER_MODULE(pcfclock, ppbus, pcfclock_driver, pcfclock_devclass, 0, 0);
339