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RTC: Cleanup rtc_class_ops->irq_set_freq()
[android-x86/kernel.git] / drivers / rtc / rtc-sh.c
1 /*
2  * SuperH On-Chip RTC Support
3  *
4  * Copyright (C) 2006 - 2009  Paul Mundt
5  * Copyright (C) 2006  Jamie Lenehan
6  * Copyright (C) 2008  Angelo Castello
7  *
8  * Based on the old arch/sh/kernel/cpu/rtc.c by:
9  *
10  *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
11  *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
12  *
13  * This file is subject to the terms and conditions of the GNU General Public
14  * License.  See the file "COPYING" in the main directory of this archive
15  * for more details.
16  */
17 #include <linux/module.h>
18 #include <linux/kernel.h>
19 #include <linux/bcd.h>
20 #include <linux/rtc.h>
21 #include <linux/init.h>
22 #include <linux/platform_device.h>
23 #include <linux/seq_file.h>
24 #include <linux/interrupt.h>
25 #include <linux/spinlock.h>
26 #include <linux/io.h>
27 #include <linux/log2.h>
28 #include <linux/clk.h>
29 #include <linux/slab.h>
30 #include <asm/rtc.h>
31
32 #define DRV_NAME        "sh-rtc"
33 #define DRV_VERSION     "0.2.3"
34
35 #define RTC_REG(r)      ((r) * rtc_reg_size)
36
37 #define R64CNT          RTC_REG(0)
38
39 #define RSECCNT         RTC_REG(1)      /* RTC sec */
40 #define RMINCNT         RTC_REG(2)      /* RTC min */
41 #define RHRCNT          RTC_REG(3)      /* RTC hour */
42 #define RWKCNT          RTC_REG(4)      /* RTC week */
43 #define RDAYCNT         RTC_REG(5)      /* RTC day */
44 #define RMONCNT         RTC_REG(6)      /* RTC month */
45 #define RYRCNT          RTC_REG(7)      /* RTC year */
46 #define RSECAR          RTC_REG(8)      /* ALARM sec */
47 #define RMINAR          RTC_REG(9)      /* ALARM min */
48 #define RHRAR           RTC_REG(10)     /* ALARM hour */
49 #define RWKAR           RTC_REG(11)     /* ALARM week */
50 #define RDAYAR          RTC_REG(12)     /* ALARM day */
51 #define RMONAR          RTC_REG(13)     /* ALARM month */
52 #define RCR1            RTC_REG(14)     /* Control */
53 #define RCR2            RTC_REG(15)     /* Control */
54
55 /*
56  * Note on RYRAR and RCR3: Up until this point most of the register
57  * definitions are consistent across all of the available parts. However,
58  * the placement of the optional RYRAR and RCR3 (the RYRAR control
59  * register used to control RYRCNT/RYRAR compare) varies considerably
60  * across various parts, occasionally being mapped in to a completely
61  * unrelated address space. For proper RYRAR support a separate resource
62  * would have to be handed off, but as this is purely optional in
63  * practice, we simply opt not to support it, thereby keeping the code
64  * quite a bit more simplified.
65  */
66
67 /* ALARM Bits - or with BCD encoded value */
68 #define AR_ENB          0x80    /* Enable for alarm cmp   */
69
70 /* Period Bits */
71 #define PF_HP           0x100   /* Enable Half Period to support 8,32,128Hz */
72 #define PF_COUNT        0x200   /* Half periodic counter */
73 #define PF_OXS          0x400   /* Periodic One x Second */
74 #define PF_KOU          0x800   /* Kernel or User periodic request 1=kernel */
75 #define PF_MASK         0xf00
76
77 /* RCR1 Bits */
78 #define RCR1_CF         0x80    /* Carry Flag             */
79 #define RCR1_CIE        0x10    /* Carry Interrupt Enable */
80 #define RCR1_AIE        0x08    /* Alarm Interrupt Enable */
81 #define RCR1_AF         0x01    /* Alarm Flag             */
82
83 /* RCR2 Bits */
84 #define RCR2_PEF        0x80    /* PEriodic interrupt Flag */
85 #define RCR2_PESMASK    0x70    /* Periodic interrupt Set  */
86 #define RCR2_RTCEN      0x08    /* ENable RTC              */
87 #define RCR2_ADJ        0x04    /* ADJustment (30-second)  */
88 #define RCR2_RESET      0x02    /* Reset bit               */
89 #define RCR2_START      0x01    /* Start bit               */
90
91 struct sh_rtc {
92         void __iomem            *regbase;
93         unsigned long           regsize;
94         struct resource         *res;
95         int                     alarm_irq;
96         int                     periodic_irq;
97         int                     carry_irq;
98         struct clk              *clk;
99         struct rtc_device       *rtc_dev;
100         spinlock_t              lock;
101         unsigned long           capabilities;   /* See asm/rtc.h for cap bits */
102         unsigned short          periodic_freq;
103 };
104
105 static int __sh_rtc_interrupt(struct sh_rtc *rtc)
106 {
107         unsigned int tmp, pending;
108
109         tmp = readb(rtc->regbase + RCR1);
110         pending = tmp & RCR1_CF;
111         tmp &= ~RCR1_CF;
112         writeb(tmp, rtc->regbase + RCR1);
113
114         /* Users have requested One x Second IRQ */
115         if (pending && rtc->periodic_freq & PF_OXS)
116                 rtc_update_irq(rtc->rtc_dev, 1, RTC_UF | RTC_IRQF);
117
118         return pending;
119 }
120
121 static int __sh_rtc_alarm(struct sh_rtc *rtc)
122 {
123         unsigned int tmp, pending;
124
125         tmp = readb(rtc->regbase + RCR1);
126         pending = tmp & RCR1_AF;
127         tmp &= ~(RCR1_AF | RCR1_AIE);
128         writeb(tmp, rtc->regbase + RCR1);
129
130         if (pending)
131                 rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
132
133         return pending;
134 }
135
136 static int __sh_rtc_periodic(struct sh_rtc *rtc)
137 {
138         struct rtc_device *rtc_dev = rtc->rtc_dev;
139         struct rtc_task *irq_task;
140         unsigned int tmp, pending;
141
142         tmp = readb(rtc->regbase + RCR2);
143         pending = tmp & RCR2_PEF;
144         tmp &= ~RCR2_PEF;
145         writeb(tmp, rtc->regbase + RCR2);
146
147         if (!pending)
148                 return 0;
149
150         /* Half period enabled than one skipped and the next notified */
151         if ((rtc->periodic_freq & PF_HP) && (rtc->periodic_freq & PF_COUNT))
152                 rtc->periodic_freq &= ~PF_COUNT;
153         else {
154                 if (rtc->periodic_freq & PF_HP)
155                         rtc->periodic_freq |= PF_COUNT;
156                 if (rtc->periodic_freq & PF_KOU) {
157                         spin_lock(&rtc_dev->irq_task_lock);
158                         irq_task = rtc_dev->irq_task;
159                         if (irq_task)
160                                 irq_task->func(irq_task->private_data);
161                         spin_unlock(&rtc_dev->irq_task_lock);
162                 } else
163                         rtc_update_irq(rtc->rtc_dev, 1, RTC_PF | RTC_IRQF);
164         }
165
166         return pending;
167 }
168
169 static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id)
170 {
171         struct sh_rtc *rtc = dev_id;
172         int ret;
173
174         spin_lock(&rtc->lock);
175         ret = __sh_rtc_interrupt(rtc);
176         spin_unlock(&rtc->lock);
177
178         return IRQ_RETVAL(ret);
179 }
180
181 static irqreturn_t sh_rtc_alarm(int irq, void *dev_id)
182 {
183         struct sh_rtc *rtc = dev_id;
184         int ret;
185
186         spin_lock(&rtc->lock);
187         ret = __sh_rtc_alarm(rtc);
188         spin_unlock(&rtc->lock);
189
190         return IRQ_RETVAL(ret);
191 }
192
193 static irqreturn_t sh_rtc_periodic(int irq, void *dev_id)
194 {
195         struct sh_rtc *rtc = dev_id;
196         int ret;
197
198         spin_lock(&rtc->lock);
199         ret = __sh_rtc_periodic(rtc);
200         spin_unlock(&rtc->lock);
201
202         return IRQ_RETVAL(ret);
203 }
204
205 static irqreturn_t sh_rtc_shared(int irq, void *dev_id)
206 {
207         struct sh_rtc *rtc = dev_id;
208         int ret;
209
210         spin_lock(&rtc->lock);
211         ret = __sh_rtc_interrupt(rtc);
212         ret |= __sh_rtc_alarm(rtc);
213         ret |= __sh_rtc_periodic(rtc);
214         spin_unlock(&rtc->lock);
215
216         return IRQ_RETVAL(ret);
217 }
218
219 static int sh_rtc_irq_set_state(struct device *dev, int enable)
220 {
221         struct sh_rtc *rtc = dev_get_drvdata(dev);
222         unsigned int tmp;
223
224         spin_lock_irq(&rtc->lock);
225
226         tmp = readb(rtc->regbase + RCR2);
227
228         if (enable) {
229                 rtc->periodic_freq |= PF_KOU;
230                 tmp &= ~RCR2_PEF;       /* Clear PES bit */
231                 tmp |= (rtc->periodic_freq & ~PF_HP);   /* Set PES2-0 */
232         } else {
233                 rtc->periodic_freq &= ~PF_KOU;
234                 tmp &= ~(RCR2_PESMASK | RCR2_PEF);
235         }
236
237         writeb(tmp, rtc->regbase + RCR2);
238
239         spin_unlock_irq(&rtc->lock);
240
241         return 0;
242 }
243
244 static int sh_rtc_irq_set_freq(struct device *dev, int freq)
245 {
246         struct sh_rtc *rtc = dev_get_drvdata(dev);
247         int tmp, ret = 0;
248
249         spin_lock_irq(&rtc->lock);
250         tmp = rtc->periodic_freq & PF_MASK;
251
252         switch (freq) {
253         case 0:
254                 rtc->periodic_freq = 0x00;
255                 break;
256         case 1:
257                 rtc->periodic_freq = 0x60;
258                 break;
259         case 2:
260                 rtc->periodic_freq = 0x50;
261                 break;
262         case 4:
263                 rtc->periodic_freq = 0x40;
264                 break;
265         case 8:
266                 rtc->periodic_freq = 0x30 | PF_HP;
267                 break;
268         case 16:
269                 rtc->periodic_freq = 0x30;
270                 break;
271         case 32:
272                 rtc->periodic_freq = 0x20 | PF_HP;
273                 break;
274         case 64:
275                 rtc->periodic_freq = 0x20;
276                 break;
277         case 128:
278                 rtc->periodic_freq = 0x10 | PF_HP;
279                 break;
280         case 256:
281                 rtc->periodic_freq = 0x10;
282                 break;
283         default:
284                 ret = -ENOTSUPP;
285         }
286
287         if (ret == 0)
288                 rtc->periodic_freq |= tmp;
289
290         spin_unlock_irq(&rtc->lock);
291         return ret;
292 }
293
294 static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
295 {
296         struct sh_rtc *rtc = dev_get_drvdata(dev);
297         unsigned int tmp;
298
299         spin_lock_irq(&rtc->lock);
300
301         tmp = readb(rtc->regbase + RCR1);
302
303         if (enable)
304                 tmp |= RCR1_AIE;
305         else
306                 tmp &= ~RCR1_AIE;
307
308         writeb(tmp, rtc->regbase + RCR1);
309
310         spin_unlock_irq(&rtc->lock);
311 }
312
313 static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
314 {
315         struct sh_rtc *rtc = dev_get_drvdata(dev);
316         unsigned int tmp;
317
318         tmp = readb(rtc->regbase + RCR1);
319         seq_printf(seq, "carry_IRQ\t: %s\n", (tmp & RCR1_CIE) ? "yes" : "no");
320
321         tmp = readb(rtc->regbase + RCR2);
322         seq_printf(seq, "periodic_IRQ\t: %s\n",
323                    (tmp & RCR2_PESMASK) ? "yes" : "no");
324
325         return 0;
326 }
327
328 static inline void sh_rtc_setcie(struct device *dev, unsigned int enable)
329 {
330         struct sh_rtc *rtc = dev_get_drvdata(dev);
331         unsigned int tmp;
332
333         spin_lock_irq(&rtc->lock);
334
335         tmp = readb(rtc->regbase + RCR1);
336
337         if (!enable)
338                 tmp &= ~RCR1_CIE;
339         else
340                 tmp |= RCR1_CIE;
341
342         writeb(tmp, rtc->regbase + RCR1);
343
344         spin_unlock_irq(&rtc->lock);
345 }
346
347 static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
348 {
349         struct sh_rtc *rtc = dev_get_drvdata(dev);
350         unsigned int ret = 0;
351
352         switch (cmd) {
353         case RTC_UIE_OFF:
354                 rtc->periodic_freq &= ~PF_OXS;
355                 sh_rtc_setcie(dev, 0);
356                 break;
357         case RTC_UIE_ON:
358                 rtc->periodic_freq |= PF_OXS;
359                 sh_rtc_setcie(dev, 1);
360                 break;
361         default:
362                 ret = -ENOIOCTLCMD;
363         }
364
365         return ret;
366 }
367
368 static int sh_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
369 {
370         sh_rtc_setaie(dev, enabled);
371         return 0;
372 }
373
374 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
375 {
376         struct platform_device *pdev = to_platform_device(dev);
377         struct sh_rtc *rtc = platform_get_drvdata(pdev);
378         unsigned int sec128, sec2, yr, yr100, cf_bit;
379
380         do {
381                 unsigned int tmp;
382
383                 spin_lock_irq(&rtc->lock);
384
385                 tmp = readb(rtc->regbase + RCR1);
386                 tmp &= ~RCR1_CF; /* Clear CF-bit */
387                 tmp |= RCR1_CIE;
388                 writeb(tmp, rtc->regbase + RCR1);
389
390                 sec128 = readb(rtc->regbase + R64CNT);
391
392                 tm->tm_sec      = bcd2bin(readb(rtc->regbase + RSECCNT));
393                 tm->tm_min      = bcd2bin(readb(rtc->regbase + RMINCNT));
394                 tm->tm_hour     = bcd2bin(readb(rtc->regbase + RHRCNT));
395                 tm->tm_wday     = bcd2bin(readb(rtc->regbase + RWKCNT));
396                 tm->tm_mday     = bcd2bin(readb(rtc->regbase + RDAYCNT));
397                 tm->tm_mon      = bcd2bin(readb(rtc->regbase + RMONCNT)) - 1;
398
399                 if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
400                         yr  = readw(rtc->regbase + RYRCNT);
401                         yr100 = bcd2bin(yr >> 8);
402                         yr &= 0xff;
403                 } else {
404                         yr  = readb(rtc->regbase + RYRCNT);
405                         yr100 = bcd2bin((yr == 0x99) ? 0x19 : 0x20);
406                 }
407
408                 tm->tm_year = (yr100 * 100 + bcd2bin(yr)) - 1900;
409
410                 sec2 = readb(rtc->regbase + R64CNT);
411                 cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
412
413                 spin_unlock_irq(&rtc->lock);
414         } while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
415
416 #if RTC_BIT_INVERTED != 0
417         if ((sec128 & RTC_BIT_INVERTED))
418                 tm->tm_sec--;
419 #endif
420
421         /* only keep the carry interrupt enabled if UIE is on */
422         if (!(rtc->periodic_freq & PF_OXS))
423                 sh_rtc_setcie(dev, 0);
424
425         dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
426                 "mday=%d, mon=%d, year=%d, wday=%d\n",
427                 __func__,
428                 tm->tm_sec, tm->tm_min, tm->tm_hour,
429                 tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
430
431         return rtc_valid_tm(tm);
432 }
433
434 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
435 {
436         struct platform_device *pdev = to_platform_device(dev);
437         struct sh_rtc *rtc = platform_get_drvdata(pdev);
438         unsigned int tmp;
439         int year;
440
441         spin_lock_irq(&rtc->lock);
442
443         /* Reset pre-scaler & stop RTC */
444         tmp = readb(rtc->regbase + RCR2);
445         tmp |= RCR2_RESET;
446         tmp &= ~RCR2_START;
447         writeb(tmp, rtc->regbase + RCR2);
448
449         writeb(bin2bcd(tm->tm_sec),  rtc->regbase + RSECCNT);
450         writeb(bin2bcd(tm->tm_min),  rtc->regbase + RMINCNT);
451         writeb(bin2bcd(tm->tm_hour), rtc->regbase + RHRCNT);
452         writeb(bin2bcd(tm->tm_wday), rtc->regbase + RWKCNT);
453         writeb(bin2bcd(tm->tm_mday), rtc->regbase + RDAYCNT);
454         writeb(bin2bcd(tm->tm_mon + 1), rtc->regbase + RMONCNT);
455
456         if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
457                 year = (bin2bcd((tm->tm_year + 1900) / 100) << 8) |
458                         bin2bcd(tm->tm_year % 100);
459                 writew(year, rtc->regbase + RYRCNT);
460         } else {
461                 year = tm->tm_year % 100;
462                 writeb(bin2bcd(year), rtc->regbase + RYRCNT);
463         }
464
465         /* Start RTC */
466         tmp = readb(rtc->regbase + RCR2);
467         tmp &= ~RCR2_RESET;
468         tmp |= RCR2_RTCEN | RCR2_START;
469         writeb(tmp, rtc->regbase + RCR2);
470
471         spin_unlock_irq(&rtc->lock);
472
473         return 0;
474 }
475
476 static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
477 {
478         unsigned int byte;
479         int value = 0xff;       /* return 0xff for ignored values */
480
481         byte = readb(rtc->regbase + reg_off);
482         if (byte & AR_ENB) {
483                 byte &= ~AR_ENB;        /* strip the enable bit */
484                 value = bcd2bin(byte);
485         }
486
487         return value;
488 }
489
490 static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
491 {
492         struct platform_device *pdev = to_platform_device(dev);
493         struct sh_rtc *rtc = platform_get_drvdata(pdev);
494         struct rtc_time *tm = &wkalrm->time;
495
496         spin_lock_irq(&rtc->lock);
497
498         tm->tm_sec      = sh_rtc_read_alarm_value(rtc, RSECAR);
499         tm->tm_min      = sh_rtc_read_alarm_value(rtc, RMINAR);
500         tm->tm_hour     = sh_rtc_read_alarm_value(rtc, RHRAR);
501         tm->tm_wday     = sh_rtc_read_alarm_value(rtc, RWKAR);
502         tm->tm_mday     = sh_rtc_read_alarm_value(rtc, RDAYAR);
503         tm->tm_mon      = sh_rtc_read_alarm_value(rtc, RMONAR);
504         if (tm->tm_mon > 0)
505                 tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
506         tm->tm_year     = 0xffff;
507
508         wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0;
509
510         spin_unlock_irq(&rtc->lock);
511
512         return 0;
513 }
514
515 static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc,
516                                             int value, int reg_off)
517 {
518         /* < 0 for a value that is ignored */
519         if (value < 0)
520                 writeb(0, rtc->regbase + reg_off);
521         else
522                 writeb(bin2bcd(value) | AR_ENB,  rtc->regbase + reg_off);
523 }
524
525 static int sh_rtc_check_alarm(struct rtc_time *tm)
526 {
527         /*
528          * The original rtc says anything > 0xc0 is "don't care" or "match
529          * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
530          * The original rtc doesn't support years - some things use -1 and
531          * some 0xffff. We use -1 to make out tests easier.
532          */
533         if (tm->tm_year == 0xffff)
534                 tm->tm_year = -1;
535         if (tm->tm_mon >= 0xff)
536                 tm->tm_mon = -1;
537         if (tm->tm_mday >= 0xff)
538                 tm->tm_mday = -1;
539         if (tm->tm_wday >= 0xff)
540                 tm->tm_wday = -1;
541         if (tm->tm_hour >= 0xff)
542                 tm->tm_hour = -1;
543         if (tm->tm_min >= 0xff)
544                 tm->tm_min = -1;
545         if (tm->tm_sec >= 0xff)
546                 tm->tm_sec = -1;
547
548         if (tm->tm_year > 9999 ||
549                 tm->tm_mon >= 12 ||
550                 tm->tm_mday == 0 || tm->tm_mday >= 32 ||
551                 tm->tm_wday >= 7 ||
552                 tm->tm_hour >= 24 ||
553                 tm->tm_min >= 60 ||
554                 tm->tm_sec >= 60)
555                 return -EINVAL;
556
557         return 0;
558 }
559
560 static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
561 {
562         struct platform_device *pdev = to_platform_device(dev);
563         struct sh_rtc *rtc = platform_get_drvdata(pdev);
564         unsigned int rcr1;
565         struct rtc_time *tm = &wkalrm->time;
566         int mon, err;
567
568         err = sh_rtc_check_alarm(tm);
569         if (unlikely(err < 0))
570                 return err;
571
572         spin_lock_irq(&rtc->lock);
573
574         /* disable alarm interrupt and clear the alarm flag */
575         rcr1 = readb(rtc->regbase + RCR1);
576         rcr1 &= ~(RCR1_AF | RCR1_AIE);
577         writeb(rcr1, rtc->regbase + RCR1);
578
579         /* set alarm time */
580         sh_rtc_write_alarm_value(rtc, tm->tm_sec,  RSECAR);
581         sh_rtc_write_alarm_value(rtc, tm->tm_min,  RMINAR);
582         sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR);
583         sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR);
584         sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR);
585         mon = tm->tm_mon;
586         if (mon >= 0)
587                 mon += 1;
588         sh_rtc_write_alarm_value(rtc, mon, RMONAR);
589
590         if (wkalrm->enabled) {
591                 rcr1 |= RCR1_AIE;
592                 writeb(rcr1, rtc->regbase + RCR1);
593         }
594
595         spin_unlock_irq(&rtc->lock);
596
597         return 0;
598 }
599
600 static struct rtc_class_ops sh_rtc_ops = {
601         .ioctl          = sh_rtc_ioctl,
602         .read_time      = sh_rtc_read_time,
603         .set_time       = sh_rtc_set_time,
604         .read_alarm     = sh_rtc_read_alarm,
605         .set_alarm      = sh_rtc_set_alarm,
606         .proc           = sh_rtc_proc,
607         .alarm_irq_enable = sh_rtc_alarm_irq_enable,
608 };
609
610 static int __init sh_rtc_probe(struct platform_device *pdev)
611 {
612         struct sh_rtc *rtc;
613         struct resource *res;
614         struct rtc_time r;
615         char clk_name[6];
616         int clk_id, ret;
617
618         rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
619         if (unlikely(!rtc))
620                 return -ENOMEM;
621
622         spin_lock_init(&rtc->lock);
623
624         /* get periodic/carry/alarm irqs */
625         ret = platform_get_irq(pdev, 0);
626         if (unlikely(ret <= 0)) {
627                 ret = -ENOENT;
628                 dev_err(&pdev->dev, "No IRQ resource\n");
629                 goto err_badres;
630         }
631
632         rtc->periodic_irq = ret;
633         rtc->carry_irq = platform_get_irq(pdev, 1);
634         rtc->alarm_irq = platform_get_irq(pdev, 2);
635
636         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
637         if (unlikely(res == NULL)) {
638                 ret = -ENOENT;
639                 dev_err(&pdev->dev, "No IO resource\n");
640                 goto err_badres;
641         }
642
643         rtc->regsize = resource_size(res);
644
645         rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
646         if (unlikely(!rtc->res)) {
647                 ret = -EBUSY;
648                 goto err_badres;
649         }
650
651         rtc->regbase = ioremap_nocache(rtc->res->start, rtc->regsize);
652         if (unlikely(!rtc->regbase)) {
653                 ret = -EINVAL;
654                 goto err_badmap;
655         }
656
657         clk_id = pdev->id;
658         /* With a single device, the clock id is still "rtc0" */
659         if (clk_id < 0)
660                 clk_id = 0;
661
662         snprintf(clk_name, sizeof(clk_name), "rtc%d", clk_id);
663
664         rtc->clk = clk_get(&pdev->dev, clk_name);
665         if (IS_ERR(rtc->clk)) {
666                 /*
667                  * No error handling for rtc->clk intentionally, not all
668                  * platforms will have a unique clock for the RTC, and
669                  * the clk API can handle the struct clk pointer being
670                  * NULL.
671                  */
672                 rtc->clk = NULL;
673         }
674
675         clk_enable(rtc->clk);
676
677         rtc->capabilities = RTC_DEF_CAPABILITIES;
678         if (pdev->dev.platform_data) {
679                 struct sh_rtc_platform_info *pinfo = pdev->dev.platform_data;
680
681                 /*
682                  * Some CPUs have special capabilities in addition to the
683                  * default set. Add those in here.
684                  */
685                 rtc->capabilities |= pinfo->capabilities;
686         }
687
688         if (rtc->carry_irq <= 0) {
689                 /* register shared periodic/carry/alarm irq */
690                 ret = request_irq(rtc->periodic_irq, sh_rtc_shared,
691                                   IRQF_DISABLED, "sh-rtc", rtc);
692                 if (unlikely(ret)) {
693                         dev_err(&pdev->dev,
694                                 "request IRQ failed with %d, IRQ %d\n", ret,
695                                 rtc->periodic_irq);
696                         goto err_unmap;
697                 }
698         } else {
699                 /* register periodic/carry/alarm irqs */
700                 ret = request_irq(rtc->periodic_irq, sh_rtc_periodic,
701                                   IRQF_DISABLED, "sh-rtc period", rtc);
702                 if (unlikely(ret)) {
703                         dev_err(&pdev->dev,
704                                 "request period IRQ failed with %d, IRQ %d\n",
705                                 ret, rtc->periodic_irq);
706                         goto err_unmap;
707                 }
708
709                 ret = request_irq(rtc->carry_irq, sh_rtc_interrupt,
710                                   IRQF_DISABLED, "sh-rtc carry", rtc);
711                 if (unlikely(ret)) {
712                         dev_err(&pdev->dev,
713                                 "request carry IRQ failed with %d, IRQ %d\n",
714                                 ret, rtc->carry_irq);
715                         free_irq(rtc->periodic_irq, rtc);
716                         goto err_unmap;
717                 }
718
719                 ret = request_irq(rtc->alarm_irq, sh_rtc_alarm,
720                                   IRQF_DISABLED, "sh-rtc alarm", rtc);
721                 if (unlikely(ret)) {
722                         dev_err(&pdev->dev,
723                                 "request alarm IRQ failed with %d, IRQ %d\n",
724                                 ret, rtc->alarm_irq);
725                         free_irq(rtc->carry_irq, rtc);
726                         free_irq(rtc->periodic_irq, rtc);
727                         goto err_unmap;
728                 }
729         }
730
731         platform_set_drvdata(pdev, rtc);
732
733         /* everything disabled by default */
734         sh_rtc_irq_set_freq(&pdev->dev, 0);
735         sh_rtc_irq_set_state(&pdev->dev, 0);
736         sh_rtc_setaie(&pdev->dev, 0);
737         sh_rtc_setcie(&pdev->dev, 0);
738
739         rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
740                                            &sh_rtc_ops, THIS_MODULE);
741         if (IS_ERR(rtc->rtc_dev)) {
742                 ret = PTR_ERR(rtc->rtc_dev);
743                 free_irq(rtc->periodic_irq, rtc);
744                 free_irq(rtc->carry_irq, rtc);
745                 free_irq(rtc->alarm_irq, rtc);
746                 goto err_unmap;
747         }
748
749         rtc->rtc_dev->max_user_freq = 256;
750
751         /* reset rtc to epoch 0 if time is invalid */
752         if (rtc_read_time(rtc->rtc_dev, &r) < 0) {
753                 rtc_time_to_tm(0, &r);
754                 rtc_set_time(rtc->rtc_dev, &r);
755         }
756
757         device_init_wakeup(&pdev->dev, 1);
758         return 0;
759
760 err_unmap:
761         clk_disable(rtc->clk);
762         clk_put(rtc->clk);
763         iounmap(rtc->regbase);
764 err_badmap:
765         release_mem_region(rtc->res->start, rtc->regsize);
766 err_badres:
767         kfree(rtc);
768
769         return ret;
770 }
771
772 static int __exit sh_rtc_remove(struct platform_device *pdev)
773 {
774         struct sh_rtc *rtc = platform_get_drvdata(pdev);
775
776         rtc_device_unregister(rtc->rtc_dev);
777         sh_rtc_irq_set_state(&pdev->dev, 0);
778
779         sh_rtc_setaie(&pdev->dev, 0);
780         sh_rtc_setcie(&pdev->dev, 0);
781
782         free_irq(rtc->periodic_irq, rtc);
783
784         if (rtc->carry_irq > 0) {
785                 free_irq(rtc->carry_irq, rtc);
786                 free_irq(rtc->alarm_irq, rtc);
787         }
788
789         iounmap(rtc->regbase);
790         release_mem_region(rtc->res->start, rtc->regsize);
791
792         clk_disable(rtc->clk);
793         clk_put(rtc->clk);
794
795         platform_set_drvdata(pdev, NULL);
796
797         kfree(rtc);
798
799         return 0;
800 }
801
802 static void sh_rtc_set_irq_wake(struct device *dev, int enabled)
803 {
804         struct platform_device *pdev = to_platform_device(dev);
805         struct sh_rtc *rtc = platform_get_drvdata(pdev);
806
807         set_irq_wake(rtc->periodic_irq, enabled);
808
809         if (rtc->carry_irq > 0) {
810                 set_irq_wake(rtc->carry_irq, enabled);
811                 set_irq_wake(rtc->alarm_irq, enabled);
812         }
813 }
814
815 static int sh_rtc_suspend(struct device *dev)
816 {
817         if (device_may_wakeup(dev))
818                 sh_rtc_set_irq_wake(dev, 1);
819
820         return 0;
821 }
822
823 static int sh_rtc_resume(struct device *dev)
824 {
825         if (device_may_wakeup(dev))
826                 sh_rtc_set_irq_wake(dev, 0);
827
828         return 0;
829 }
830
831 static const struct dev_pm_ops sh_rtc_dev_pm_ops = {
832         .suspend = sh_rtc_suspend,
833         .resume = sh_rtc_resume,
834 };
835
836 static struct platform_driver sh_rtc_platform_driver = {
837         .driver         = {
838                 .name   = DRV_NAME,
839                 .owner  = THIS_MODULE,
840                 .pm     = &sh_rtc_dev_pm_ops,
841         },
842         .remove         = __exit_p(sh_rtc_remove),
843 };
844
845 static int __init sh_rtc_init(void)
846 {
847         return platform_driver_probe(&sh_rtc_platform_driver, sh_rtc_probe);
848 }
849
850 static void __exit sh_rtc_exit(void)
851 {
852         platform_driver_unregister(&sh_rtc_platform_driver);
853 }
854
855 module_init(sh_rtc_init);
856 module_exit(sh_rtc_exit);
857
858 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
859 MODULE_VERSION(DRV_VERSION);
860 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, "
861               "Jamie Lenehan <lenehan@twibble.org>, "
862               "Angelo Castello <angelo.castello@st.com>");
863 MODULE_LICENSE("GPL");
864 MODULE_ALIAS("platform:" DRV_NAME);