1 /*-
2 * Copyright (c) 2015 Luiz Otavio O Souza <loos@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29
30 /*
31 * Driver for Maxim DS1307 I2C real-time clock/calendar.
32 */
33
34 #include "opt_platform.h"
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/bus.h>
39 #include <sys/clock.h>
40 #include <sys/kernel.h>
41 #include <sys/module.h>
42 #include <sys/sysctl.h>
43
44 #include <dev/iicbus/iicbus.h>
45 #include <dev/iicbus/iiconf.h>
46 #ifdef FDT
47 #include <dev/ofw/openfirm.h>
48 #include <dev/ofw/ofw_bus.h>
49 #include <dev/ofw/ofw_bus_subr.h>
50 #endif
51
52 #include <dev/iicbus/ds1307reg.h>
53
54 #include "clock_if.h"
55 #include "iicbus_if.h"
56
57 struct ds1307_softc {
58 device_t sc_dev;
59 struct intr_config_hook
60 enum_hook;
61 uint8_t sc_ctrl;
62 bool sc_mcp7941x;
63 bool sc_use_ampm;
64 };
65
66 static void ds1307_start(void *);
67
68 #ifdef FDT
69 static const struct ofw_compat_data ds1307_compat_data[] = {
70 {"dallas,ds1307", (uintptr_t)"Dallas DS1307 RTC"},
71 {"maxim,ds1307", (uintptr_t)"Maxim DS1307 RTC"},
72 {"microchip,mcp7941x", (uintptr_t)"Microchip MCP7941x RTC"},
73 { NULL, 0 }
74 };
75 #endif
76
77 static int
ds1307_read1(device_t dev,uint8_t reg,uint8_t * data)78 ds1307_read1(device_t dev, uint8_t reg, uint8_t *data)
79 {
80
81 return (iicdev_readfrom(dev, reg, data, 1, IIC_INTRWAIT));
82 }
83
84 static int
ds1307_write1(device_t dev,uint8_t reg,uint8_t data)85 ds1307_write1(device_t dev, uint8_t reg, uint8_t data)
86 {
87
88 return (iicdev_writeto(dev, reg, &data, 1, IIC_INTRWAIT));
89 }
90
91 static int
ds1307_ctrl_read(struct ds1307_softc * sc)92 ds1307_ctrl_read(struct ds1307_softc *sc)
93 {
94 int error;
95
96 sc->sc_ctrl = 0;
97 error = ds1307_read1(sc->sc_dev, DS1307_CONTROL, &sc->sc_ctrl);
98 if (error) {
99 device_printf(sc->sc_dev, "cannot read from RTC.\n");
100 return (error);
101 }
102
103 return (0);
104 }
105
106 static int
ds1307_ctrl_write(struct ds1307_softc * sc)107 ds1307_ctrl_write(struct ds1307_softc *sc)
108 {
109 int error;
110 uint8_t ctrl;
111
112 ctrl = sc->sc_ctrl & DS1307_CTRL_MASK;
113 error = ds1307_write1(sc->sc_dev, DS1307_CONTROL, ctrl);
114 if (error != 0)
115 device_printf(sc->sc_dev, "cannot write to RTC.\n");
116
117 return (error);
118 }
119
120 static int
ds1307_sqwe_sysctl(SYSCTL_HANDLER_ARGS)121 ds1307_sqwe_sysctl(SYSCTL_HANDLER_ARGS)
122 {
123 int sqwe, error, newv, sqwe_bit;
124 struct ds1307_softc *sc;
125
126 sc = (struct ds1307_softc *)arg1;
127 error = ds1307_ctrl_read(sc);
128 if (error != 0)
129 return (error);
130 if (sc->sc_mcp7941x)
131 sqwe_bit = MCP7941X_CTRL_SQWE;
132 else
133 sqwe_bit = DS1307_CTRL_SQWE;
134 sqwe = newv = (sc->sc_ctrl & sqwe_bit) ? 1 : 0;
135 error = sysctl_handle_int(oidp, &newv, 0, req);
136 if (error != 0 || req->newptr == NULL)
137 return (error);
138 if (sqwe != newv) {
139 sc->sc_ctrl &= ~sqwe_bit;
140 if (newv)
141 sc->sc_ctrl |= sqwe_bit;
142 error = ds1307_ctrl_write(sc);
143 if (error != 0)
144 return (error);
145 }
146
147 return (error);
148 }
149
150 static int
ds1307_sqw_freq_sysctl(SYSCTL_HANDLER_ARGS)151 ds1307_sqw_freq_sysctl(SYSCTL_HANDLER_ARGS)
152 {
153 int ds1307_sqw_freq[] = { 1, 4096, 8192, 32768 };
154 int error, freq, i, newf, tmp;
155 struct ds1307_softc *sc;
156
157 sc = (struct ds1307_softc *)arg1;
158 error = ds1307_ctrl_read(sc);
159 if (error != 0)
160 return (error);
161 tmp = (sc->sc_ctrl & DS1307_CTRL_RS_MASK);
162 if (tmp >= nitems(ds1307_sqw_freq))
163 tmp = nitems(ds1307_sqw_freq) - 1;
164 freq = ds1307_sqw_freq[tmp];
165 error = sysctl_handle_int(oidp, &freq, 0, req);
166 if (error != 0 || req->newptr == NULL)
167 return (error);
168 if (freq != ds1307_sqw_freq[tmp]) {
169 newf = 0;
170 for (i = 0; i < nitems(ds1307_sqw_freq); i++)
171 if (freq >= ds1307_sqw_freq[i])
172 newf = i;
173 sc->sc_ctrl &= ~DS1307_CTRL_RS_MASK;
174 sc->sc_ctrl |= newf;
175 error = ds1307_ctrl_write(sc);
176 if (error != 0)
177 return (error);
178 }
179
180 return (error);
181 }
182
183 static int
ds1307_sqw_out_sysctl(SYSCTL_HANDLER_ARGS)184 ds1307_sqw_out_sysctl(SYSCTL_HANDLER_ARGS)
185 {
186 int sqwe, error, newv;
187 struct ds1307_softc *sc;
188
189 sc = (struct ds1307_softc *)arg1;
190 error = ds1307_ctrl_read(sc);
191 if (error != 0)
192 return (error);
193 sqwe = newv = (sc->sc_ctrl & DS1307_CTRL_OUT) ? 1 : 0;
194 error = sysctl_handle_int(oidp, &newv, 0, req);
195 if (error != 0 || req->newptr == NULL)
196 return (error);
197 if (sqwe != newv) {
198 sc->sc_ctrl &= ~DS1307_CTRL_OUT;
199 if (newv)
200 sc->sc_ctrl |= DS1307_CTRL_OUT;
201 error = ds1307_ctrl_write(sc);
202 if (error != 0)
203 return (error);
204 }
205
206 return (error);
207 }
208
209 static int
ds1307_probe(device_t dev)210 ds1307_probe(device_t dev)
211 {
212 #ifdef FDT
213 const struct ofw_compat_data *compat;
214
215 if (!ofw_bus_status_okay(dev))
216 return (ENXIO);
217
218 compat = ofw_bus_search_compatible(dev, ds1307_compat_data);
219
220 if (compat->ocd_str == NULL)
221 return (ENXIO);
222
223 device_set_desc(dev, (const char *)compat->ocd_data);
224
225 return (BUS_PROBE_DEFAULT);
226 #else
227 device_set_desc(dev, "Maxim DS1307 RTC");
228
229 return (BUS_PROBE_NOWILDCARD);
230 #endif
231 }
232
233 static int
ds1307_attach(device_t dev)234 ds1307_attach(device_t dev)
235 {
236 struct ds1307_softc *sc;
237
238 sc = device_get_softc(dev);
239 sc->sc_dev = dev;
240 sc->enum_hook.ich_func = ds1307_start;
241 sc->enum_hook.ich_arg = dev;
242
243 #ifdef FDT
244 if (ofw_bus_is_compatible(dev, "microchip,mcp7941x"))
245 sc->sc_mcp7941x = 1;
246 #endif
247
248 /*
249 * We have to wait until interrupts are enabled. Usually I2C read
250 * and write only works when the interrupts are available.
251 */
252 if (config_intrhook_establish(&sc->enum_hook) != 0)
253 return (ENOMEM);
254
255 return (0);
256 }
257
258 static int
ds1307_detach(device_t dev)259 ds1307_detach(device_t dev)
260 {
261
262 clock_unregister(dev);
263 return (0);
264 }
265
266 static void
ds1307_start(void * xdev)267 ds1307_start(void *xdev)
268 {
269 device_t dev;
270 struct ds1307_softc *sc;
271 struct sysctl_ctx_list *ctx;
272 struct sysctl_oid *tree_node;
273 struct sysctl_oid_list *tree;
274 uint8_t secs;
275 uint8_t osc_en;
276
277 dev = (device_t)xdev;
278 sc = device_get_softc(dev);
279 ctx = device_get_sysctl_ctx(dev);
280 tree_node = device_get_sysctl_tree(dev);
281 tree = SYSCTL_CHILDREN(tree_node);
282
283 config_intrhook_disestablish(&sc->enum_hook);
284
285 /* Check if the oscillator is disabled. */
286 if (ds1307_read1(sc->sc_dev, DS1307_SECS, &secs) != 0) {
287 device_printf(sc->sc_dev, "cannot read from RTC.\n");
288 return;
289 }
290 if (sc->sc_mcp7941x)
291 osc_en = 0x80;
292 else
293 osc_en = 0x00;
294
295 if (((secs & DS1307_SECS_CH) ^ osc_en) != 0) {
296 device_printf(sc->sc_dev,
297 "WARNING: RTC clock stopped, check the battery.\n");
298 }
299
300 /* Configuration parameters. */
301 SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "sqwe",
302 CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_MPSAFE, sc, 0,
303 ds1307_sqwe_sysctl, "IU", "DS1307 square-wave enable");
304 SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "sqw_freq",
305 CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_MPSAFE, sc, 0,
306 ds1307_sqw_freq_sysctl, "IU",
307 "DS1307 square-wave output frequency");
308 SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "sqw_out",
309 CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_MPSAFE, sc, 0,
310 ds1307_sqw_out_sysctl, "IU", "DS1307 square-wave output state");
311
312 /*
313 * Register as a clock with 1 second resolution. Schedule the
314 * clock_settime() method to be called just after top-of-second;
315 * resetting the time resets top-of-second in the hardware.
316 */
317 clock_register_flags(dev, 1000000, CLOCKF_SETTIME_NO_ADJ);
318 clock_schedule(dev, 1);
319 }
320
321 static int
ds1307_gettime(device_t dev,struct timespec * ts)322 ds1307_gettime(device_t dev, struct timespec *ts)
323 {
324 int error;
325 struct bcd_clocktime bct;
326 struct ds1307_softc *sc;
327 uint8_t data[7], hourmask, st_mask;
328
329 sc = device_get_softc(dev);
330 error = iicdev_readfrom(sc->sc_dev, DS1307_SECS, data, sizeof(data),
331 IIC_INTRWAIT);
332 if (error != 0) {
333 device_printf(dev, "cannot read from RTC.\n");
334 return (error);
335 }
336
337 /* If the clock halted, we don't have good data. */
338 if (sc->sc_mcp7941x)
339 st_mask = 0x80;
340 else
341 st_mask = 0x00;
342
343 if (((data[DS1307_SECS] & DS1307_SECS_CH) ^ st_mask) != 0)
344 return (EINVAL);
345
346 /* If chip is in AM/PM mode remember that. */
347 if (data[DS1307_HOUR] & DS1307_HOUR_USE_AMPM) {
348 sc->sc_use_ampm = true;
349 hourmask = DS1307_HOUR_MASK_12HR;
350 } else
351 hourmask = DS1307_HOUR_MASK_24HR;
352
353 bct.nsec = 0;
354 bct.ispm = (data[DS1307_HOUR] & DS1307_HOUR_IS_PM) != 0;
355 bct.sec = data[DS1307_SECS] & DS1307_SECS_MASK;
356 bct.min = data[DS1307_MINS] & DS1307_MINS_MASK;
357 bct.hour = data[DS1307_HOUR] & hourmask;
358 bct.day = data[DS1307_DATE] & DS1307_DATE_MASK;
359 bct.mon = data[DS1307_MONTH] & DS1307_MONTH_MASK;
360 bct.year = data[DS1307_YEAR] & DS1307_YEAR_MASK;
361
362 clock_dbgprint_bcd(sc->sc_dev, CLOCK_DBG_READ, &bct);
363 return (clock_bcd_to_ts(&bct, ts, sc->sc_use_ampm));
364 }
365
366 static int
ds1307_settime(device_t dev,struct timespec * ts)367 ds1307_settime(device_t dev, struct timespec *ts)
368 {
369 struct bcd_clocktime bct;
370 struct ds1307_softc *sc;
371 int error, year;
372 uint8_t data[7];
373 uint8_t pmflags;
374
375 sc = device_get_softc(dev);
376
377 /*
378 * We request a timespec with no resolution-adjustment. That also
379 * disables utc adjustment, so apply that ourselves.
380 */
381 ts->tv_sec -= utc_offset();
382 clock_ts_to_bcd(ts, &bct, sc->sc_use_ampm);
383 clock_dbgprint_bcd(sc->sc_dev, CLOCK_DBG_WRITE, &bct);
384
385 /* If the chip is in AM/PM mode, adjust hour and set flags as needed. */
386 if (sc->sc_use_ampm) {
387 pmflags = DS1307_HOUR_USE_AMPM;
388 if (bct.ispm)
389 pmflags |= DS1307_HOUR_IS_PM;
390 } else
391 pmflags = 0;
392
393 data[DS1307_SECS] = bct.sec;
394 data[DS1307_MINS] = bct.min;
395 data[DS1307_HOUR] = bct.hour | pmflags;
396 data[DS1307_DATE] = bct.day;
397 data[DS1307_WEEKDAY] = bct.dow;
398 data[DS1307_MONTH] = bct.mon;
399 data[DS1307_YEAR] = bct.year & 0xff;
400 if (sc->sc_mcp7941x) {
401 data[DS1307_SECS] |= MCP7941X_SECS_ST;
402 data[DS1307_WEEKDAY] |= MCP7941X_WEEKDAY_VBATEN;
403 year = bcd2bin(bct.year >> 8) * 100 + bcd2bin(bct.year & 0xff);
404 if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0)
405 data[DS1307_MONTH] |= MCP7941X_MONTH_LPYR;
406 }
407 /* Write the time back to RTC. */
408 error = iicdev_writeto(sc->sc_dev, DS1307_SECS, data, sizeof(data),
409 IIC_INTRWAIT);
410 if (error != 0)
411 device_printf(dev, "cannot write to RTC.\n");
412
413 return (error);
414 }
415
416 static device_method_t ds1307_methods[] = {
417 DEVMETHOD(device_probe, ds1307_probe),
418 DEVMETHOD(device_attach, ds1307_attach),
419 DEVMETHOD(device_detach, ds1307_detach),
420
421 DEVMETHOD(clock_gettime, ds1307_gettime),
422 DEVMETHOD(clock_settime, ds1307_settime),
423
424 DEVMETHOD_END
425 };
426
427 static driver_t ds1307_driver = {
428 "ds1307",
429 ds1307_methods,
430 sizeof(struct ds1307_softc),
431 };
432
433 static devclass_t ds1307_devclass;
434
435 DRIVER_MODULE(ds1307, iicbus, ds1307_driver, ds1307_devclass, NULL, NULL);
436 MODULE_VERSION(ds1307, 1);
437 MODULE_DEPEND(ds1307, iicbus, 1, 1, 1);
438