rtc: New RTC driver for SuperH On-Chip RTC.
[linux-2.6.git] / drivers / rtc / rtc-sh.c
1 /*
2  * SuperH On-Chip RTC Support
3  *
4  * Copyright (C) 2006  Paul Mundt
5  *
6  * Based on the old arch/sh/kernel/cpu/rtc.c by:
7  *
8  *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
9  *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
10  *
11  * This file is subject to the terms and conditions of the GNU General Public
12  * License.  See the file "COPYING" in the main directory of this archive
13  * for more details.
14  */
15 #include <linux/module.h>
16 #include <linux/kernel.h>
17 #include <linux/bcd.h>
18 #include <linux/rtc.h>
19 #include <linux/init.h>
20 #include <linux/platform_device.h>
21 #include <linux/seq_file.h>
22 #include <linux/interrupt.h>
23 #include <linux/spinlock.h>
24 #include <asm/io.h>
25
26 #ifdef CONFIG_CPU_SH3
27 #define rtc_reg_size            sizeof(u16)
28 #define RTC_BIT_INVERTED        0       /* No bug on SH7708, SH7709A */
29 #elif defined(CONFIG_CPU_SH4)
30 #define rtc_reg_size            sizeof(u32)
31 #define RTC_BIT_INVERTED        0x40    /* bug on SH7750, SH7750S */
32 #endif
33
34 #define RTC_REG(r)      ((r) * rtc_reg_size)
35
36 #define R64CNT          RTC_REG(0)
37 #define RSECCNT         RTC_REG(1)
38 #define RMINCNT         RTC_REG(2)
39 #define RHRCNT          RTC_REG(3)
40 #define RWKCNT          RTC_REG(4)
41 #define RDAYCNT         RTC_REG(5)
42 #define RMONCNT         RTC_REG(6)
43 #define RYRCNT          RTC_REG(7)
44 #define RSECAR          RTC_REG(8)
45 #define RMINAR          RTC_REG(9)
46 #define RHRAR           RTC_REG(10)
47 #define RWKAR           RTC_REG(11)
48 #define RDAYAR          RTC_REG(12)
49 #define RMONAR          RTC_REG(13)
50 #define RCR1            RTC_REG(14)
51 #define RCR2            RTC_REG(15)
52
53 /* RCR1 Bits */
54 #define RCR1_CF         0x80    /* Carry Flag             */
55 #define RCR1_CIE        0x10    /* Carry Interrupt Enable */
56 #define RCR1_AIE        0x08    /* Alarm Interrupt Enable */
57 #define RCR1_AF         0x01    /* Alarm Flag             */
58
59 /* RCR2 Bits */
60 #define RCR2_PEF        0x80    /* PEriodic interrupt Flag */
61 #define RCR2_PESMASK    0x70    /* Periodic interrupt Set  */
62 #define RCR2_RTCEN      0x08    /* ENable RTC              */
63 #define RCR2_ADJ        0x04    /* ADJustment (30-second)  */
64 #define RCR2_RESET      0x02    /* Reset bit               */
65 #define RCR2_START      0x01    /* Start bit               */
66
67 struct sh_rtc {
68         void __iomem *regbase;
69         unsigned long regsize;
70         struct resource *res;
71         unsigned int alarm_irq, periodic_irq, carry_irq;
72         struct rtc_device *rtc_dev;
73         spinlock_t lock;
74 };
75
76 static irqreturn_t sh_rtc_interrupt(int irq, void *id, struct pt_regs *regs)
77 {
78         struct platform_device *pdev = id;
79         struct sh_rtc *rtc = platform_get_drvdata(pdev);
80         unsigned int tmp, events = 0;
81
82         spin_lock(&rtc->lock);
83
84         tmp = readb(rtc->regbase + RCR1);
85
86         if (tmp & RCR1_AF)
87                 events |= RTC_AF | RTC_IRQF;
88
89         tmp &= ~(RCR1_CF | RCR1_AF);
90
91         writeb(tmp, rtc->regbase + RCR1);
92
93         rtc_update_irq(&rtc->rtc_dev->class_dev, 1, events);
94
95         spin_unlock(&rtc->lock);
96
97         return IRQ_HANDLED;
98 }
99
100 static irqreturn_t sh_rtc_periodic(int irq, void *id, struct pt_regs *regs)
101 {
102         struct sh_rtc *rtc = dev_get_drvdata(id);
103
104         spin_lock(&rtc->lock);
105
106         rtc_update_irq(&rtc->rtc_dev->class_dev, 1, RTC_PF | RTC_IRQF);
107
108         spin_unlock(&rtc->lock);
109
110         return IRQ_HANDLED;
111 }
112
113 static inline void sh_rtc_setpie(struct device *dev, unsigned int enable)
114 {
115         struct sh_rtc *rtc = dev_get_drvdata(dev);
116         unsigned int tmp;
117
118         spin_lock_irq(&rtc->lock);
119
120         tmp = readb(rtc->regbase + RCR2);
121
122         if (enable) {
123                 tmp &= ~RCR2_PESMASK;
124                 tmp |= RCR2_PEF | (2 << 4);
125         } else
126                 tmp &= ~(RCR2_PESMASK | RCR2_PEF);
127
128         writeb(tmp, rtc->regbase + RCR2);
129
130         spin_unlock_irq(&rtc->lock);
131 }
132
133 static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
134 {
135         struct sh_rtc *rtc = dev_get_drvdata(dev);
136         unsigned int tmp;
137
138         spin_lock_irq(&rtc->lock);
139
140         tmp = readb(rtc->regbase + RCR1);
141
142         if (enable)
143                 tmp |= RCR1_AIE;
144         else
145                 tmp &= ~RCR1_AIE;
146
147         writeb(tmp, rtc->regbase + RCR1);
148
149         spin_unlock_irq(&rtc->lock);
150 }
151
152 static int sh_rtc_open(struct device *dev)
153 {
154         struct sh_rtc *rtc = dev_get_drvdata(dev);
155         unsigned int tmp;
156         int ret;
157
158         tmp = readb(rtc->regbase + RCR1);
159         tmp &= ~RCR1_CF;
160         tmp |= RCR1_CIE;
161         writeb(tmp, rtc->regbase + RCR1);
162
163         ret = request_irq(rtc->periodic_irq, sh_rtc_periodic, SA_INTERRUPT,
164                           "sh-rtc period", dev);
165         if (unlikely(ret)) {
166                 dev_err(dev, "request period IRQ failed with %d, IRQ %d\n",
167                         ret, rtc->periodic_irq);
168                 return ret;
169         }
170
171         ret = request_irq(rtc->carry_irq, sh_rtc_interrupt, SA_INTERRUPT,
172                           "sh-rtc carry", dev);
173         if (unlikely(ret)) {
174                 dev_err(dev, "request carry IRQ failed with %d, IRQ %d\n",
175                         ret, rtc->carry_irq);
176                 free_irq(rtc->periodic_irq, dev);
177                 goto err_bad_carry;
178         }
179
180         ret = request_irq(rtc->alarm_irq, sh_rtc_interrupt, SA_INTERRUPT,
181                           "sh-rtc alarm", dev);
182         if (unlikely(ret)) {
183                 dev_err(dev, "request alarm IRQ failed with %d, IRQ %d\n",
184                         ret, rtc->alarm_irq);
185                 goto err_bad_alarm;
186         }
187
188         return 0;
189
190 err_bad_alarm:
191         free_irq(rtc->carry_irq, dev);
192 err_bad_carry:
193         free_irq(rtc->periodic_irq, dev);
194
195         return ret;
196 }
197
198 static void sh_rtc_release(struct device *dev)
199 {
200         struct sh_rtc *rtc = dev_get_drvdata(dev);
201
202         sh_rtc_setpie(dev, 0);
203
204         free_irq(rtc->periodic_irq, dev);
205         free_irq(rtc->carry_irq, dev);
206         free_irq(rtc->alarm_irq, dev);
207 }
208
209 static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
210 {
211         struct sh_rtc *rtc = dev_get_drvdata(dev);
212         unsigned int tmp;
213
214         tmp = readb(rtc->regbase + RCR1);
215         seq_printf(seq, "alarm_IRQ\t: %s\n",
216                    (tmp & RCR1_AIE) ? "yes" : "no");
217         seq_printf(seq, "carry_IRQ\t: %s\n",
218                    (tmp & RCR1_CIE) ? "yes" : "no");
219
220         tmp = readb(rtc->regbase + RCR2);
221         seq_printf(seq, "periodic_IRQ\t: %s\n",
222                    (tmp & RCR2_PEF) ? "yes" : "no");
223
224         return 0;
225 }
226
227 static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
228 {
229         unsigned int ret = -ENOIOCTLCMD;
230
231         switch (cmd) {
232         case RTC_PIE_OFF:
233         case RTC_PIE_ON:
234                 sh_rtc_setpie(dev, cmd == RTC_PIE_ON);
235                 ret = 0;
236                 break;
237         case RTC_AIE_OFF:
238         case RTC_AIE_ON:
239                 sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
240                 ret = 0;
241                 break;
242         }
243
244         return ret;
245 }
246
247 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
248 {
249         struct platform_device *pdev = to_platform_device(dev);
250         struct sh_rtc *rtc = platform_get_drvdata(pdev);
251         unsigned int sec128, sec2, yr, yr100, cf_bit;
252
253         do {
254                 unsigned int tmp;
255
256                 spin_lock_irq(&rtc->lock);
257
258                 tmp = readb(rtc->regbase + RCR1);
259                 tmp &= ~RCR1_CF; /* Clear CF-bit */
260                 tmp |= RCR1_CIE;
261                 writeb(tmp, rtc->regbase + RCR1);
262
263                 sec128 = readb(rtc->regbase + R64CNT);
264
265                 tm->tm_sec      = BCD2BIN(readb(rtc->regbase + RSECCNT));
266                 tm->tm_min      = BCD2BIN(readb(rtc->regbase + RMINCNT));
267                 tm->tm_hour     = BCD2BIN(readb(rtc->regbase + RHRCNT));
268                 tm->tm_wday     = BCD2BIN(readb(rtc->regbase + RWKCNT));
269                 tm->tm_mday     = BCD2BIN(readb(rtc->regbase + RDAYCNT));
270                 tm->tm_mon      = BCD2BIN(readb(rtc->regbase + RMONCNT));
271
272 #if defined(CONFIG_CPU_SH4)
273                 yr  = readw(rtc->regbase + RYRCNT);
274                 yr100 = BCD2BIN(yr >> 8);
275                 yr &= 0xff;
276 #else
277                 yr  = readb(rtc->regbase + RYRCNT);
278                 yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20);
279 #endif
280
281                 tm->tm_year = (yr100 * 100 + BCD2BIN(yr)) - 1900;
282
283                 sec2 = readb(rtc->regbase + R64CNT);
284                 cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
285
286                 spin_unlock_irq(&rtc->lock);
287         } while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
288
289 #if RTC_BIT_INVERTED != 0
290         if ((sec128 & RTC_BIT_INVERTED))
291                 tm->tm_sec--;
292 #endif
293
294         dev_dbg(&dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
295                 "mday=%d, mon=%d, year=%d, wday=%d\n",
296                 __FUNCTION__,
297                 tm->tm_sec, tm->tm_min, tm->tm_hour,
298                 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
299
300         if (rtc_valid_tm(tm) < 0)
301                 dev_err(dev, "invalid date\n");
302
303         return 0;
304 }
305
306 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
307 {
308         struct platform_device *pdev = to_platform_device(dev);
309         struct sh_rtc *rtc = platform_get_drvdata(pdev);
310         unsigned int tmp;
311         int year;
312
313         spin_lock_irq(&rtc->lock);
314
315         /* Reset pre-scaler & stop RTC */
316         tmp = readb(rtc->regbase + RCR2);
317         tmp |= RCR2_RESET;
318         writeb(tmp, rtc->regbase + RCR2);
319
320         writeb(BIN2BCD(tm->tm_sec),  rtc->regbase + RSECCNT);
321         writeb(BIN2BCD(tm->tm_min),  rtc->regbase + RMINCNT);
322         writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT);
323         writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT);
324         writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT);
325         writeb(BIN2BCD(tm->tm_mon),  rtc->regbase + RMONCNT);
326
327 #ifdef CONFIG_CPU_SH3
328         year = tm->tm_year % 100;
329         writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
330 #else
331         year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) |
332                 BIN2BCD(tm->tm_year % 100);
333         writew(year, rtc->regbase + RYRCNT);
334 #endif
335
336         /* Start RTC */
337         tmp = readb(rtc->regbase + RCR2);
338         tmp &= ~RCR2_RESET;
339         tmp |= RCR2_RTCEN | RCR2_START;
340         writeb(tmp, rtc->regbase + RCR2);
341
342         spin_unlock_irq(&rtc->lock);
343
344         return 0;
345 }
346
347 static struct rtc_class_ops sh_rtc_ops = {
348         .open           = sh_rtc_open,
349         .release        = sh_rtc_release,
350         .ioctl          = sh_rtc_ioctl,
351         .read_time      = sh_rtc_read_time,
352         .set_time       = sh_rtc_set_time,
353         .proc           = sh_rtc_proc,
354 };
355
356 static int __devinit sh_rtc_probe(struct platform_device *pdev)
357 {
358         struct sh_rtc *rtc;
359         struct resource *res;
360         int ret = -ENOENT;
361
362         rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
363         if (unlikely(!rtc))
364                 return -ENOMEM;
365
366         spin_lock_init(&rtc->lock);
367
368         rtc->periodic_irq = platform_get_irq(pdev, 0);
369         if (unlikely(rtc->periodic_irq < 0)) {
370                 dev_err(&pdev->dev, "No IRQ for period\n");
371                 goto err_badres;
372         }
373
374         rtc->carry_irq = platform_get_irq(pdev, 1);
375         if (unlikely(rtc->carry_irq < 0)) {
376                 dev_err(&pdev->dev, "No IRQ for carry\n");
377                 goto err_badres;
378         }
379
380         rtc->alarm_irq = platform_get_irq(pdev, 2);
381         if (unlikely(rtc->alarm_irq < 0)) {
382                 dev_err(&pdev->dev, "No IRQ for alarm\n");
383                 goto err_badres;
384         }
385
386         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
387         if (unlikely(res == NULL)) {
388                 dev_err(&pdev->dev, "No IO resource\n");
389                 goto err_badres;
390         }
391
392         rtc->regsize = res->end - res->start + 1;
393
394         rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
395         if (unlikely(!rtc->res)) {
396                 ret = -EBUSY;
397                 goto err_badres;
398         }
399
400         rtc->regbase = (void __iomem *)rtc->res->start;
401         if (unlikely(!rtc->regbase)) {
402                 ret = -EINVAL;
403                 goto err_badmap;
404         }
405
406         rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
407                                            &sh_rtc_ops, THIS_MODULE);
408         if (IS_ERR(rtc)) {
409                 ret = PTR_ERR(rtc->rtc_dev);
410                 goto err_badmap;
411         }
412
413         platform_set_drvdata(pdev, rtc);
414
415         return 0;
416
417 err_badmap:
418         release_resource(rtc->res);
419 err_badres:
420         kfree(rtc);
421
422         return ret;
423 }
424
425 static int __devexit sh_rtc_remove(struct platform_device *pdev)
426 {
427         struct sh_rtc *rtc = platform_get_drvdata(pdev);
428
429         if (likely(rtc->rtc_dev))
430                 rtc_device_unregister(rtc->rtc_dev);
431
432         sh_rtc_setpie(&pdev->dev, 0);
433         sh_rtc_setaie(&pdev->dev, 0);
434
435         release_resource(rtc->res);
436
437         platform_set_drvdata(pdev, NULL);
438
439         kfree(rtc);
440
441         return 0;
442 }
443 static struct platform_driver sh_rtc_platform_driver = {
444         .driver         = {
445                 .name   = "sh-rtc",
446                 .owner  = THIS_MODULE,
447         },
448         .probe          = sh_rtc_probe,
449         .remove         = __devexit_p(sh_rtc_remove),
450 };
451
452 static int __init sh_rtc_init(void)
453 {
454         return platform_driver_register(&sh_rtc_platform_driver);
455 }
456
457 static void __exit sh_rtc_exit(void)
458 {
459         platform_driver_unregister(&sh_rtc_platform_driver);
460 }
461
462 module_init(sh_rtc_init);
463 module_exit(sh_rtc_exit);
464
465 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
466 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
467 MODULE_LICENSE("GPL");