xref: /openbmc/linux/drivers/input/misc/hp_sdc_rtc.c (revision 63dc02bd)
1 /*
2  * HP i8042 SDC + MSM-58321 BBRTC driver.
3  *
4  * Copyright (c) 2001 Brian S. Julin
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions, and the following disclaimer,
12  *    without modification.
13  * 2. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * Alternatively, this software may be distributed under the terms of the
17  * GNU General Public License ("GPL").
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
23  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  *
29  * References:
30  * System Device Controller Microprocessor Firmware Theory of Operation
31  *      for Part Number 1820-4784 Revision B.  Dwg No. A-1820-4784-2
32  * efirtc.c by Stephane Eranian/Hewlett Packard
33  *
34  */
35 
36 #include <linux/hp_sdc.h>
37 #include <linux/errno.h>
38 #include <linux/types.h>
39 #include <linux/init.h>
40 #include <linux/module.h>
41 #include <linux/time.h>
42 #include <linux/miscdevice.h>
43 #include <linux/proc_fs.h>
44 #include <linux/poll.h>
45 #include <linux/rtc.h>
46 #include <linux/mutex.h>
47 #include <linux/semaphore.h>
48 
49 MODULE_AUTHOR("Brian S. Julin <bri@calyx.com>");
50 MODULE_DESCRIPTION("HP i8042 SDC + MSM-58321 RTC Driver");
51 MODULE_LICENSE("Dual BSD/GPL");
52 
53 #define RTC_VERSION "1.10d"
54 
55 static DEFINE_MUTEX(hp_sdc_rtc_mutex);
56 static unsigned long epoch = 2000;
57 
58 static struct semaphore i8042tregs;
59 
60 static hp_sdc_irqhook hp_sdc_rtc_isr;
61 
62 static struct fasync_struct *hp_sdc_rtc_async_queue;
63 
64 static DECLARE_WAIT_QUEUE_HEAD(hp_sdc_rtc_wait);
65 
66 static ssize_t hp_sdc_rtc_read(struct file *file, char __user *buf,
67 			       size_t count, loff_t *ppos);
68 
69 static long hp_sdc_rtc_unlocked_ioctl(struct file *file,
70 				      unsigned int cmd, unsigned long arg);
71 
72 static unsigned int hp_sdc_rtc_poll(struct file *file, poll_table *wait);
73 
74 static int hp_sdc_rtc_open(struct inode *inode, struct file *file);
75 static int hp_sdc_rtc_fasync (int fd, struct file *filp, int on);
76 
77 static int hp_sdc_rtc_read_proc(char *page, char **start, off_t off,
78 				int count, int *eof, void *data);
79 
80 static void hp_sdc_rtc_isr (int irq, void *dev_id,
81 			    uint8_t status, uint8_t data)
82 {
83 	return;
84 }
85 
86 static int hp_sdc_rtc_do_read_bbrtc (struct rtc_time *rtctm)
87 {
88 	struct semaphore tsem;
89 	hp_sdc_transaction t;
90 	uint8_t tseq[91];
91 	int i;
92 
93 	i = 0;
94 	while (i < 91) {
95 		tseq[i++] = HP_SDC_ACT_DATAREG |
96 			HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN;
97 		tseq[i++] = 0x01;			/* write i8042[0x70] */
98 	  	tseq[i]   = i / 7;			/* BBRTC reg address */
99 		i++;
100 		tseq[i++] = HP_SDC_CMD_DO_RTCR;		/* Trigger command   */
101 		tseq[i++] = 2;		/* expect 1 stat/dat pair back.   */
102 		i++; i++;               /* buffer for stat/dat pair       */
103 	}
104 	tseq[84] |= HP_SDC_ACT_SEMAPHORE;
105 	t.endidx =		91;
106 	t.seq =			tseq;
107 	t.act.semaphore =	&tsem;
108 	sema_init(&tsem, 0);
109 
110 	if (hp_sdc_enqueue_transaction(&t)) return -1;
111 
112 	down_interruptible(&tsem);  /* Put ourselves to sleep for results. */
113 
114 	/* Check for nonpresence of BBRTC */
115 	if (!((tseq[83] | tseq[90] | tseq[69] | tseq[76] |
116 	       tseq[55] | tseq[62] | tseq[34] | tseq[41] |
117 	       tseq[20] | tseq[27] | tseq[6]  | tseq[13]) & 0x0f))
118 		return -1;
119 
120 	memset(rtctm, 0, sizeof(struct rtc_time));
121 	rtctm->tm_year = (tseq[83] & 0x0f) + (tseq[90] & 0x0f) * 10;
122 	rtctm->tm_mon  = (tseq[69] & 0x0f) + (tseq[76] & 0x0f) * 10;
123 	rtctm->tm_mday = (tseq[55] & 0x0f) + (tseq[62] & 0x0f) * 10;
124 	rtctm->tm_wday = (tseq[48] & 0x0f);
125 	rtctm->tm_hour = (tseq[34] & 0x0f) + (tseq[41] & 0x0f) * 10;
126 	rtctm->tm_min  = (tseq[20] & 0x0f) + (tseq[27] & 0x0f) * 10;
127 	rtctm->tm_sec  = (tseq[6]  & 0x0f) + (tseq[13] & 0x0f) * 10;
128 
129 	return 0;
130 }
131 
132 static int hp_sdc_rtc_read_bbrtc (struct rtc_time *rtctm)
133 {
134 	struct rtc_time tm, tm_last;
135 	int i = 0;
136 
137 	/* MSM-58321 has no read latch, so must read twice and compare. */
138 
139 	if (hp_sdc_rtc_do_read_bbrtc(&tm_last)) return -1;
140 	if (hp_sdc_rtc_do_read_bbrtc(&tm)) return -1;
141 
142 	while (memcmp(&tm, &tm_last, sizeof(struct rtc_time))) {
143 		if (i++ > 4) return -1;
144 		memcpy(&tm_last, &tm, sizeof(struct rtc_time));
145 		if (hp_sdc_rtc_do_read_bbrtc(&tm)) return -1;
146 	}
147 
148 	memcpy(rtctm, &tm, sizeof(struct rtc_time));
149 
150 	return 0;
151 }
152 
153 
154 static int64_t hp_sdc_rtc_read_i8042timer (uint8_t loadcmd, int numreg)
155 {
156 	hp_sdc_transaction t;
157 	uint8_t tseq[26] = {
158 		HP_SDC_ACT_PRECMD | HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
159 		0,
160 		HP_SDC_CMD_READ_T1, 2, 0, 0,
161 		HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
162 		HP_SDC_CMD_READ_T2, 2, 0, 0,
163 		HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
164 		HP_SDC_CMD_READ_T3, 2, 0, 0,
165 		HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
166 		HP_SDC_CMD_READ_T4, 2, 0, 0,
167 		HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
168 		HP_SDC_CMD_READ_T5, 2, 0, 0
169 	};
170 
171 	t.endidx = numreg * 5;
172 
173 	tseq[1] = loadcmd;
174 	tseq[t.endidx - 4] |= HP_SDC_ACT_SEMAPHORE; /* numreg assumed > 1 */
175 
176 	t.seq =			tseq;
177 	t.act.semaphore =	&i8042tregs;
178 
179 	down_interruptible(&i8042tregs);  /* Sleep if output regs in use. */
180 
181 	if (hp_sdc_enqueue_transaction(&t)) return -1;
182 
183 	down_interruptible(&i8042tregs);  /* Sleep until results come back. */
184 	up(&i8042tregs);
185 
186 	return (tseq[5] |
187 		((uint64_t)(tseq[10]) << 8)  | ((uint64_t)(tseq[15]) << 16) |
188 		((uint64_t)(tseq[20]) << 24) | ((uint64_t)(tseq[25]) << 32));
189 }
190 
191 
192 /* Read the i8042 real-time clock */
193 static inline int hp_sdc_rtc_read_rt(struct timeval *res) {
194 	int64_t raw;
195 	uint32_t tenms;
196 	unsigned int days;
197 
198 	raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_RT, 5);
199 	if (raw < 0) return -1;
200 
201 	tenms = (uint32_t)raw & 0xffffff;
202 	days  = (unsigned int)(raw >> 24) & 0xffff;
203 
204 	res->tv_usec = (suseconds_t)(tenms % 100) * 10000;
205 	res->tv_sec =  (time_t)(tenms / 100) + days * 86400;
206 
207 	return 0;
208 }
209 
210 
211 /* Read the i8042 fast handshake timer */
212 static inline int hp_sdc_rtc_read_fhs(struct timeval *res) {
213 	int64_t raw;
214 	unsigned int tenms;
215 
216 	raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_FHS, 2);
217 	if (raw < 0) return -1;
218 
219 	tenms = (unsigned int)raw & 0xffff;
220 
221 	res->tv_usec = (suseconds_t)(tenms % 100) * 10000;
222 	res->tv_sec  = (time_t)(tenms / 100);
223 
224 	return 0;
225 }
226 
227 
228 /* Read the i8042 match timer (a.k.a. alarm) */
229 static inline int hp_sdc_rtc_read_mt(struct timeval *res) {
230 	int64_t raw;
231 	uint32_t tenms;
232 
233 	raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_MT, 3);
234 	if (raw < 0) return -1;
235 
236 	tenms = (uint32_t)raw & 0xffffff;
237 
238 	res->tv_usec = (suseconds_t)(tenms % 100) * 10000;
239 	res->tv_sec  = (time_t)(tenms / 100);
240 
241 	return 0;
242 }
243 
244 
245 /* Read the i8042 delay timer */
246 static inline int hp_sdc_rtc_read_dt(struct timeval *res) {
247 	int64_t raw;
248 	uint32_t tenms;
249 
250 	raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_DT, 3);
251 	if (raw < 0) return -1;
252 
253 	tenms = (uint32_t)raw & 0xffffff;
254 
255 	res->tv_usec = (suseconds_t)(tenms % 100) * 10000;
256 	res->tv_sec  = (time_t)(tenms / 100);
257 
258 	return 0;
259 }
260 
261 
262 /* Read the i8042 cycle timer (a.k.a. periodic) */
263 static inline int hp_sdc_rtc_read_ct(struct timeval *res) {
264 	int64_t raw;
265 	uint32_t tenms;
266 
267 	raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_CT, 3);
268 	if (raw < 0) return -1;
269 
270 	tenms = (uint32_t)raw & 0xffffff;
271 
272 	res->tv_usec = (suseconds_t)(tenms % 100) * 10000;
273 	res->tv_sec  = (time_t)(tenms / 100);
274 
275 	return 0;
276 }
277 
278 
279 /* Set the i8042 real-time clock */
280 static int hp_sdc_rtc_set_rt (struct timeval *setto)
281 {
282 	uint32_t tenms;
283 	unsigned int days;
284 	hp_sdc_transaction t;
285 	uint8_t tseq[11] = {
286 		HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT,
287 		HP_SDC_CMD_SET_RTMS, 3, 0, 0, 0,
288 		HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT,
289 		HP_SDC_CMD_SET_RTD, 2, 0, 0
290 	};
291 
292 	t.endidx = 10;
293 
294 	if (0xffff < setto->tv_sec / 86400) return -1;
295 	days = setto->tv_sec / 86400;
296 	if (0xffff < setto->tv_usec / 1000000 / 86400) return -1;
297 	days += ((setto->tv_sec % 86400) + setto->tv_usec / 1000000) / 86400;
298 	if (days > 0xffff) return -1;
299 
300 	if (0xffffff < setto->tv_sec) return -1;
301 	tenms  = setto->tv_sec * 100;
302 	if (0xffffff < setto->tv_usec / 10000) return -1;
303 	tenms += setto->tv_usec / 10000;
304 	if (tenms > 0xffffff) return -1;
305 
306 	tseq[3] = (uint8_t)(tenms & 0xff);
307 	tseq[4] = (uint8_t)((tenms >> 8)  & 0xff);
308 	tseq[5] = (uint8_t)((tenms >> 16) & 0xff);
309 
310 	tseq[9] = (uint8_t)(days & 0xff);
311 	tseq[10] = (uint8_t)((days >> 8) & 0xff);
312 
313 	t.seq =	tseq;
314 
315 	if (hp_sdc_enqueue_transaction(&t)) return -1;
316 	return 0;
317 }
318 
319 /* Set the i8042 fast handshake timer */
320 static int hp_sdc_rtc_set_fhs (struct timeval *setto)
321 {
322 	uint32_t tenms;
323 	hp_sdc_transaction t;
324 	uint8_t tseq[5] = {
325 		HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT,
326 		HP_SDC_CMD_SET_FHS, 2, 0, 0
327 	};
328 
329 	t.endidx = 4;
330 
331 	if (0xffff < setto->tv_sec) return -1;
332 	tenms  = setto->tv_sec * 100;
333 	if (0xffff < setto->tv_usec / 10000) return -1;
334 	tenms += setto->tv_usec / 10000;
335 	if (tenms > 0xffff) return -1;
336 
337 	tseq[3] = (uint8_t)(tenms & 0xff);
338 	tseq[4] = (uint8_t)((tenms >> 8)  & 0xff);
339 
340 	t.seq =	tseq;
341 
342 	if (hp_sdc_enqueue_transaction(&t)) return -1;
343 	return 0;
344 }
345 
346 
347 /* Set the i8042 match timer (a.k.a. alarm) */
348 #define hp_sdc_rtc_set_mt (setto) \
349 	hp_sdc_rtc_set_i8042timer(setto, HP_SDC_CMD_SET_MT)
350 
351 /* Set the i8042 delay timer */
352 #define hp_sdc_rtc_set_dt (setto) \
353 	hp_sdc_rtc_set_i8042timer(setto, HP_SDC_CMD_SET_DT)
354 
355 /* Set the i8042 cycle timer (a.k.a. periodic) */
356 #define hp_sdc_rtc_set_ct (setto) \
357 	hp_sdc_rtc_set_i8042timer(setto, HP_SDC_CMD_SET_CT)
358 
359 /* Set one of the i8042 3-byte wide timers */
360 static int hp_sdc_rtc_set_i8042timer (struct timeval *setto, uint8_t setcmd)
361 {
362 	uint32_t tenms;
363 	hp_sdc_transaction t;
364 	uint8_t tseq[6] = {
365 		HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT,
366 		0, 3, 0, 0, 0
367 	};
368 
369 	t.endidx = 6;
370 
371 	if (0xffffff < setto->tv_sec) return -1;
372 	tenms  = setto->tv_sec * 100;
373 	if (0xffffff < setto->tv_usec / 10000) return -1;
374 	tenms += setto->tv_usec / 10000;
375 	if (tenms > 0xffffff) return -1;
376 
377 	tseq[1] = setcmd;
378 	tseq[3] = (uint8_t)(tenms & 0xff);
379 	tseq[4] = (uint8_t)((tenms >> 8)  & 0xff);
380 	tseq[5] = (uint8_t)((tenms >> 16)  & 0xff);
381 
382 	t.seq =			tseq;
383 
384 	if (hp_sdc_enqueue_transaction(&t)) {
385 		return -1;
386 	}
387 	return 0;
388 }
389 
390 static ssize_t hp_sdc_rtc_read(struct file *file, char __user *buf,
391 			       size_t count, loff_t *ppos) {
392 	ssize_t retval;
393 
394         if (count < sizeof(unsigned long))
395                 return -EINVAL;
396 
397 	retval = put_user(68, (unsigned long __user *)buf);
398 	return retval;
399 }
400 
401 static unsigned int hp_sdc_rtc_poll(struct file *file, poll_table *wait)
402 {
403         unsigned long l;
404 
405 	l = 0;
406         if (l != 0)
407                 return POLLIN | POLLRDNORM;
408         return 0;
409 }
410 
411 static int hp_sdc_rtc_open(struct inode *inode, struct file *file)
412 {
413         return 0;
414 }
415 
416 static int hp_sdc_rtc_fasync (int fd, struct file *filp, int on)
417 {
418         return fasync_helper (fd, filp, on, &hp_sdc_rtc_async_queue);
419 }
420 
421 static int hp_sdc_rtc_proc_output (char *buf)
422 {
423 #define YN(bit) ("no")
424 #define NY(bit) ("yes")
425         char *p;
426         struct rtc_time tm;
427 	struct timeval tv;
428 
429 	memset(&tm, 0, sizeof(struct rtc_time));
430 
431 	p = buf;
432 
433 	if (hp_sdc_rtc_read_bbrtc(&tm)) {
434 		p += sprintf(p, "BBRTC\t\t: READ FAILED!\n");
435 	} else {
436 		p += sprintf(p,
437 			     "rtc_time\t: %02d:%02d:%02d\n"
438 			     "rtc_date\t: %04d-%02d-%02d\n"
439 			     "rtc_epoch\t: %04lu\n",
440 			     tm.tm_hour, tm.tm_min, tm.tm_sec,
441 			     tm.tm_year + 1900, tm.tm_mon + 1,
442 			     tm.tm_mday, epoch);
443 	}
444 
445 	if (hp_sdc_rtc_read_rt(&tv)) {
446 		p += sprintf(p, "i8042 rtc\t: READ FAILED!\n");
447 	} else {
448 		p += sprintf(p, "i8042 rtc\t: %ld.%02d seconds\n",
449 			     tv.tv_sec, (int)tv.tv_usec/1000);
450 	}
451 
452 	if (hp_sdc_rtc_read_fhs(&tv)) {
453 		p += sprintf(p, "handshake\t: READ FAILED!\n");
454 	} else {
455         	p += sprintf(p, "handshake\t: %ld.%02d seconds\n",
456 			     tv.tv_sec, (int)tv.tv_usec/1000);
457 	}
458 
459 	if (hp_sdc_rtc_read_mt(&tv)) {
460 		p += sprintf(p, "alarm\t\t: READ FAILED!\n");
461 	} else {
462 		p += sprintf(p, "alarm\t\t: %ld.%02d seconds\n",
463 			     tv.tv_sec, (int)tv.tv_usec/1000);
464 	}
465 
466 	if (hp_sdc_rtc_read_dt(&tv)) {
467 		p += sprintf(p, "delay\t\t: READ FAILED!\n");
468 	} else {
469 		p += sprintf(p, "delay\t\t: %ld.%02d seconds\n",
470 			     tv.tv_sec, (int)tv.tv_usec/1000);
471 	}
472 
473 	if (hp_sdc_rtc_read_ct(&tv)) {
474 		p += sprintf(p, "periodic\t: READ FAILED!\n");
475 	} else {
476 		p += sprintf(p, "periodic\t: %ld.%02d seconds\n",
477 			     tv.tv_sec, (int)tv.tv_usec/1000);
478 	}
479 
480         p += sprintf(p,
481                      "DST_enable\t: %s\n"
482                      "BCD\t\t: %s\n"
483                      "24hr\t\t: %s\n"
484                      "square_wave\t: %s\n"
485                      "alarm_IRQ\t: %s\n"
486                      "update_IRQ\t: %s\n"
487                      "periodic_IRQ\t: %s\n"
488 		     "periodic_freq\t: %ld\n"
489                      "batt_status\t: %s\n",
490                      YN(RTC_DST_EN),
491                      NY(RTC_DM_BINARY),
492                      YN(RTC_24H),
493                      YN(RTC_SQWE),
494                      YN(RTC_AIE),
495                      YN(RTC_UIE),
496                      YN(RTC_PIE),
497                      1UL,
498                      1 ? "okay" : "dead");
499 
500         return  p - buf;
501 #undef YN
502 #undef NY
503 }
504 
505 static int hp_sdc_rtc_read_proc(char *page, char **start, off_t off,
506                          int count, int *eof, void *data)
507 {
508 	int len = hp_sdc_rtc_proc_output (page);
509         if (len <= off+count) *eof = 1;
510         *start = page + off;
511         len -= off;
512         if (len>count) len = count;
513         if (len<0) len = 0;
514         return len;
515 }
516 
517 static int hp_sdc_rtc_ioctl(struct file *file,
518 			    unsigned int cmd, unsigned long arg)
519 {
520 #if 1
521 	return -EINVAL;
522 #else
523 
524         struct rtc_time wtime;
525 	struct timeval ttime;
526 	int use_wtime = 0;
527 
528 	/* This needs major work. */
529 
530         switch (cmd) {
531 
532         case RTC_AIE_OFF:       /* Mask alarm int. enab. bit    */
533         case RTC_AIE_ON:        /* Allow alarm interrupts.      */
534 	case RTC_PIE_OFF:       /* Mask periodic int. enab. bit */
535         case RTC_PIE_ON:        /* Allow periodic ints          */
536         case RTC_UIE_ON:        /* Allow ints for RTC updates.  */
537         case RTC_UIE_OFF:       /* Allow ints for RTC updates.  */
538         {
539 		/* We cannot mask individual user timers and we
540 		   cannot tell them apart when they occur, so it
541 		   would be disingenuous to succeed these IOCTLs */
542 		return -EINVAL;
543         }
544         case RTC_ALM_READ:      /* Read the present alarm time */
545         {
546 		if (hp_sdc_rtc_read_mt(&ttime)) return -EFAULT;
547 		if (hp_sdc_rtc_read_bbrtc(&wtime)) return -EFAULT;
548 
549 		wtime.tm_hour = ttime.tv_sec / 3600;  ttime.tv_sec %= 3600;
550 		wtime.tm_min  = ttime.tv_sec / 60;    ttime.tv_sec %= 60;
551 		wtime.tm_sec  = ttime.tv_sec;
552 
553 		break;
554         }
555         case RTC_IRQP_READ:     /* Read the periodic IRQ rate.  */
556         {
557                 return put_user(hp_sdc_rtc_freq, (unsigned long *)arg);
558         }
559         case RTC_IRQP_SET:      /* Set periodic IRQ rate.       */
560         {
561                 /*
562                  * The max we can do is 100Hz.
563 		 */
564 
565                 if ((arg < 1) || (arg > 100)) return -EINVAL;
566 		ttime.tv_sec = 0;
567 		ttime.tv_usec = 1000000 / arg;
568 		if (hp_sdc_rtc_set_ct(&ttime)) return -EFAULT;
569 		hp_sdc_rtc_freq = arg;
570                 return 0;
571         }
572         case RTC_ALM_SET:       /* Store a time into the alarm */
573         {
574                 /*
575                  * This expects a struct hp_sdc_rtc_time. Writing 0xff means
576                  * "don't care" or "match all" for PC timers.  The HP SDC
577 		 * does not support that perk, but it could be emulated fairly
578 		 * easily.  Only the tm_hour, tm_min and tm_sec are used.
579 		 * We could do it with 10ms accuracy with the HP SDC, if the
580 		 * rtc interface left us a way to do that.
581                  */
582                 struct hp_sdc_rtc_time alm_tm;
583 
584                 if (copy_from_user(&alm_tm, (struct hp_sdc_rtc_time*)arg,
585                                    sizeof(struct hp_sdc_rtc_time)))
586                        return -EFAULT;
587 
588                 if (alm_tm.tm_hour > 23) return -EINVAL;
589 		if (alm_tm.tm_min  > 59) return -EINVAL;
590 		if (alm_tm.tm_sec  > 59) return -EINVAL;
591 
592 		ttime.sec = alm_tm.tm_hour * 3600 +
593 		  alm_tm.tm_min * 60 + alm_tm.tm_sec;
594 		ttime.usec = 0;
595 		if (hp_sdc_rtc_set_mt(&ttime)) return -EFAULT;
596                 return 0;
597         }
598         case RTC_RD_TIME:       /* Read the time/date from RTC  */
599         {
600 		if (hp_sdc_rtc_read_bbrtc(&wtime)) return -EFAULT;
601                 break;
602         }
603         case RTC_SET_TIME:      /* Set the RTC */
604         {
605                 struct rtc_time hp_sdc_rtc_tm;
606                 unsigned char mon, day, hrs, min, sec, leap_yr;
607                 unsigned int yrs;
608 
609                 if (!capable(CAP_SYS_TIME))
610                         return -EACCES;
611 		if (copy_from_user(&hp_sdc_rtc_tm, (struct rtc_time *)arg,
612                                    sizeof(struct rtc_time)))
613                         return -EFAULT;
614 
615                 yrs = hp_sdc_rtc_tm.tm_year + 1900;
616                 mon = hp_sdc_rtc_tm.tm_mon + 1;   /* tm_mon starts at zero */
617                 day = hp_sdc_rtc_tm.tm_mday;
618                 hrs = hp_sdc_rtc_tm.tm_hour;
619                 min = hp_sdc_rtc_tm.tm_min;
620                 sec = hp_sdc_rtc_tm.tm_sec;
621 
622                 if (yrs < 1970)
623                         return -EINVAL;
624 
625                 leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
626 
627                 if ((mon > 12) || (day == 0))
628                         return -EINVAL;
629                 if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
630                         return -EINVAL;
631 		if ((hrs >= 24) || (min >= 60) || (sec >= 60))
632                         return -EINVAL;
633 
634                 if ((yrs -= eH) > 255)    /* They are unsigned */
635                         return -EINVAL;
636 
637 
638                 return 0;
639         }
640         case RTC_EPOCH_READ:    /* Read the epoch.      */
641         {
642                 return put_user (epoch, (unsigned long *)arg);
643         }
644         case RTC_EPOCH_SET:     /* Set the epoch.       */
645         {
646                 /*
647                  * There were no RTC clocks before 1900.
648                  */
649                 if (arg < 1900)
650 		  return -EINVAL;
651 		if (!capable(CAP_SYS_TIME))
652 		  return -EACCES;
653 
654                 epoch = arg;
655                 return 0;
656         }
657         default:
658                 return -EINVAL;
659         }
660         return copy_to_user((void *)arg, &wtime, sizeof wtime) ? -EFAULT : 0;
661 #endif
662 }
663 
664 static long hp_sdc_rtc_unlocked_ioctl(struct file *file,
665 				      unsigned int cmd, unsigned long arg)
666 {
667 	int ret;
668 
669 	mutex_lock(&hp_sdc_rtc_mutex);
670 	ret = hp_sdc_rtc_ioctl(file, cmd, arg);
671 	mutex_unlock(&hp_sdc_rtc_mutex);
672 
673 	return ret;
674 }
675 
676 
677 static const struct file_operations hp_sdc_rtc_fops = {
678         .owner =		THIS_MODULE,
679         .llseek =		no_llseek,
680         .read =			hp_sdc_rtc_read,
681         .poll =			hp_sdc_rtc_poll,
682         .unlocked_ioctl =	hp_sdc_rtc_unlocked_ioctl,
683         .open =			hp_sdc_rtc_open,
684         .fasync =		hp_sdc_rtc_fasync,
685 };
686 
687 static struct miscdevice hp_sdc_rtc_dev = {
688         .minor =	RTC_MINOR,
689         .name =		"rtc_HIL",
690         .fops =		&hp_sdc_rtc_fops
691 };
692 
693 static int __init hp_sdc_rtc_init(void)
694 {
695 	int ret;
696 
697 #ifdef __mc68000__
698 	if (!MACH_IS_HP300)
699 		return -ENODEV;
700 #endif
701 
702 	sema_init(&i8042tregs, 1);
703 
704 	if ((ret = hp_sdc_request_timer_irq(&hp_sdc_rtc_isr)))
705 		return ret;
706 	if (misc_register(&hp_sdc_rtc_dev) != 0)
707 		printk(KERN_INFO "Could not register misc. dev for i8042 rtc\n");
708 
709         create_proc_read_entry ("driver/rtc", 0, NULL,
710 				hp_sdc_rtc_read_proc, NULL);
711 
712 	printk(KERN_INFO "HP i8042 SDC + MSM-58321 RTC support loaded "
713 			 "(RTC v " RTC_VERSION ")\n");
714 
715 	return 0;
716 }
717 
718 static void __exit hp_sdc_rtc_exit(void)
719 {
720 	remove_proc_entry ("driver/rtc", NULL);
721         misc_deregister(&hp_sdc_rtc_dev);
722 	hp_sdc_release_timer_irq(hp_sdc_rtc_isr);
723         printk(KERN_INFO "HP i8042 SDC + MSM-58321 RTC support unloaded\n");
724 }
725 
726 module_init(hp_sdc_rtc_init);
727 module_exit(hp_sdc_rtc_exit);
728