summaryrefslogtreecommitdiffstats
path: root/drivers/rtc/rtc-pxa.c
blob: e6351b743da644cd78dd34b0cfd73b667e885cfe (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
/*
 * Real Time Clock interface for XScale PXA27x and PXA3xx
 *
 * Copyright (C) 2008 Robert Jarzmik
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/rtc.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
#include <linux/io.h>

#include <mach/hardware.h>

#define TIMER_FREQ		CLOCK_TICK_RATE
#define RTC_DEF_DIVIDER		(32768 - 1)
#define RTC_DEF_TRIM		0
#define MAXFREQ_PERIODIC	1000

/*
 * PXA Registers and bits definitions
 */
#define RTSR_PICE	(1 << 15)	/* Periodic interrupt count enable */
#define RTSR_PIALE	(1 << 14)	/* Periodic interrupt Alarm enable */
#define RTSR_PIAL	(1 << 13)	/* Periodic interrupt detected */
#define RTSR_SWALE2	(1 << 11)	/* RTC stopwatch alarm2 enable */
#define RTSR_SWAL2	(1 << 10)	/* RTC stopwatch alarm2 detected */
#define RTSR_SWALE1	(1 << 9)	/* RTC stopwatch alarm1 enable */
#define RTSR_SWAL1	(1 << 8)	/* RTC stopwatch alarm1 detected */
#define RTSR_RDALE2	(1 << 7)	/* RTC alarm2 enable */
#define RTSR_RDAL2	(1 << 6)	/* RTC alarm2 detected */
#define RTSR_RDALE1	(1 << 5)	/* RTC alarm1 enable */
#define RTSR_RDAL1	(1 << 4)	/* RTC alarm1 detected */
#define RTSR_HZE	(1 << 3)	/* HZ interrupt enable */
#define RTSR_ALE	(1 << 2)	/* RTC alarm interrupt enable */
#define RTSR_HZ		(1 << 1)	/* HZ rising-edge detected */
#define RTSR_AL		(1 << 0)	/* RTC alarm detected */
#define RTSR_TRIG_MASK	(RTSR_AL | RTSR_HZ | RTSR_RDAL1 | RTSR_RDAL2\
			 | RTSR_SWAL1 | RTSR_SWAL2)
#define RYxR_YEAR_S	9
#define RYxR_YEAR_MASK	(0xfff << RYxR_YEAR_S)
#define RYxR_MONTH_S	5
#define RYxR_MONTH_MASK	(0xf << RYxR_MONTH_S)
#define RYxR_DAY_MASK	0x1f
#define RDxR_HOUR_S	12
#define RDxR_HOUR_MASK	(0x1f << RDxR_HOUR_S)
#define RDxR_MIN_S	6
#define RDxR_MIN_MASK	(0x3f << RDxR_MIN_S)
#define RDxR_SEC_MASK	0x3f

#define RTSR		0x08
#define RTTR		0x0c
#define RDCR		0x10
#define RYCR		0x14
#define RDAR1		0x18
#define RYAR1		0x1c
#define RTCPICR		0x34
#define PIAR		0x38

#define rtc_readl(pxa_rtc, reg)	\
	__raw_readl((pxa_rtc)->base + (reg))
#define rtc_writel(pxa_rtc, reg, value)	\
	__raw_writel((value), (pxa_rtc)->base + (reg))

struct pxa_rtc {
	struct resource	*ress;
	void __iomem		*base;
	int			irq_1Hz;
	int			irq_Alrm;
	struct rtc_device	*rtc;
	spinlock_t		lock;		/* Protects this structure */
	struct rtc_time		rtc_alarm;
};

static u32 ryxr_calc(struct rtc_time *tm)
{
	return ((tm->tm_year + 1900) << RYxR_YEAR_S)
		| ((tm->tm_mon + 1) << RYxR_MONTH_S)
		| tm->tm_mday;
}

static u32 rdxr_calc(struct rtc_time *tm)
{
	return (tm->tm_hour << RDxR_HOUR_S) | (tm->tm_min << RDxR_MIN_S)
		| tm->tm_sec;
}

static void tm_calc(u32 rycr, u32 rdcr, struct rtc_time *tm)
{
	tm->tm_year = ((rycr & RYxR_YEAR_MASK) >> RYxR_YEAR_S) - 1900;
	tm->tm_mon = (((rycr & RYxR_MONTH_MASK) >> RYxR_MONTH_S)) - 1;
	tm->tm_mday = (rycr & RYxR_DAY_MASK);
	tm->tm_hour = (rdcr & RDxR_HOUR_MASK) >> RDxR_HOUR_S;
	tm->tm_min = (rdcr & RDxR_MIN_MASK) >> RDxR_MIN_S;
	tm->tm_sec = rdcr & RDxR_SEC_MASK;
}

static void rtsr_clear_bits(struct pxa_rtc *pxa_rtc, u32 mask)
{
	u32 rtsr;

	rtsr = rtc_readl(pxa_rtc, RTSR);
	rtsr &= ~RTSR_TRIG_MASK;
	rtsr &= ~mask;
	rtc_writel(pxa_rtc, RTSR, rtsr);
}

static void rtsr_set_bits(struct pxa_rtc *pxa_rtc, u32 mask)
{
	u32 rtsr;

	rtsr = rtc_readl(pxa_rtc, RTSR);
	rtsr &= ~RTSR_TRIG_MASK;
	rtsr |= mask;
	rtc_writel(pxa_rtc, RTSR, rtsr);
}

static irqreturn_t pxa_rtc_irq(int irq, void *dev_id)
{
	struct platform_device *pdev = to_platform_device(dev_id);
	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);
	u32 rtsr;
	unsigned long events = 0;

	spin_lock(&pxa_rtc->lock);

	/* clear interrupt sources */
	rtsr = rtc_readl(pxa_rtc, RTSR);
	rtc_writel(pxa_rtc, RTSR, rtsr);

	/* temporary disable rtc interrupts */
	rtsr_clear_bits(pxa_rtc, RTSR_RDALE1 | RTSR_PIALE | RTSR_HZE);

	/* clear alarm interrupt if it has occurred */
	if (rtsr & RTSR_RDAL1)
		rtsr &= ~RTSR_RDALE1;

	/* update irq data & counter */
	if (rtsr & RTSR_RDAL1)
		events |= RTC_AF | RTC_IRQF;
	if (rtsr & RTSR_HZ)
		events |= RTC_UF | RTC_IRQF;
	if (rtsr & RTSR_PIAL)
		events |= RTC_PF | RTC_IRQF;

	rtc_update_irq(pxa_rtc->rtc, 1, events);

	/* enable back rtc interrupts */
	rtc_writel(pxa_rtc, RTSR, rtsr & ~RTSR_TRIG_MASK);

	spin_unlock(&pxa_rtc->lock);
	return IRQ_HANDLED;
}

static int pxa_rtc_open(struct device *dev)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	int ret;

	ret = request_irq(pxa_rtc->irq_1Hz, pxa_rtc_irq, IRQF_DISABLED,
			  "rtc 1Hz", dev);
	if (ret < 0) {
		dev_err(dev, "can't get irq %i, err %d\n", pxa_rtc->irq_1Hz,
			ret);
		goto err_irq_1Hz;
	}
	ret = request_irq(pxa_rtc->irq_Alrm, pxa_rtc_irq, IRQF_DISABLED,
			  "rtc Alrm", dev);
	if (ret < 0) {
		dev_err(dev, "can't get irq %i, err %d\n", pxa_rtc->irq_Alrm,
			ret);
		goto err_irq_Alrm;
	}

	return 0;

err_irq_Alrm:
	free_irq(pxa_rtc->irq_1Hz, dev);
err_irq_1Hz:
	return ret;
}

static void pxa_rtc_release(struct device *dev)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

	spin_lock_irq(&pxa_rtc->lock);
	rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
	spin_unlock_irq(&pxa_rtc->lock);

	free_irq(pxa_rtc->irq_Alrm, dev);
	free_irq(pxa_rtc->irq_1Hz, dev);
}

static int pxa_periodic_irq_set_freq(struct device *dev, int freq)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	int period_ms;

	if (freq < 1 || freq > MAXFREQ_PERIODIC)
		return -EINVAL;

	period_ms = 1000 / freq;
	rtc_writel(pxa_rtc, PIAR, period_ms);

	return 0;
}

static int pxa_periodic_irq_set_state(struct device *dev, int enabled)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

	if (enabled)
		rtsr_set_bits(pxa_rtc, RTSR_PIALE | RTSR_PICE);
	else
		rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_PICE);

	return 0;
}

static int pxa_rtc_ioctl(struct device *dev, unsigned int cmd,
		unsigned long arg)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	int ret = 0;

	spin_lock_irq(&pxa_rtc->lock);
	switch (cmd) {
	case RTC_AIE_OFF:
		rtsr_clear_bits(pxa_rtc, RTSR_RDALE1);
		break;
	case RTC_AIE_ON:
		rtsr_set_bits(pxa_rtc, RTSR_RDALE1);
		break;
	case RTC_UIE_OFF:
		rtsr_clear_bits(pxa_rtc, RTSR_HZE);
		break;
	case RTC_UIE_ON:
		rtsr_set_bits(pxa_rtc, RTSR_HZE);
		break;
	default:
		ret = -ENOIOCTLCMD;
	}

	spin_unlock_irq(&pxa_rtc->lock);
	return ret;
}

static int pxa_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	u32 rycr, rdcr;

	rycr = rtc_readl(pxa_rtc, RYCR);
	rdcr = rtc_readl(pxa_rtc, RDCR);

	tm_calc(rycr, rdcr, tm);
	return 0;
}

static int pxa_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

	rtc_writel(pxa_rtc, RYCR, ryxr_calc(tm));
	rtc_writel(pxa_rtc, RDCR, rdxr_calc(tm));

	return 0;
}

static int pxa_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	u32 rtsr, ryar, rdar;

	ryar = rtc_readl(pxa_rtc, RYAR1);
	rdar = rtc_readl(pxa_rtc, RDAR1);
	tm_calc(ryar, rdar, &alrm->time);

	rtsr = rtc_readl(pxa_rtc, RTSR);
	alrm->enabled = (rtsr & RTSR_RDALE1) ? 1 : 0;
	alrm->pending = (rtsr & RTSR_RDAL1) ? 1 : 0;
	return 0;
}

static int pxa_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	u32 rtsr;

	spin_lock_irq(&pxa_rtc->lock);

	rtc_writel(pxa_rtc, RYAR1, ryxr_calc(&alrm->time));
	rtc_writel(pxa_rtc, RDAR1, rdxr_calc(&alrm->time));

	rtsr = rtc_readl(pxa_rtc, RTSR);
	if (alrm->enabled)
		rtsr |= RTSR_RDALE1;
	else
		rtsr &= ~RTSR_RDALE1;
	rtc_writel(pxa_rtc, RTSR, rtsr);

	spin_unlock_irq(&pxa_rtc->lock);

	return 0;
}

static int pxa_rtc_proc(struct device *dev, struct seq_file *seq)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

	seq_printf(seq, "trim/divider\t: 0x%08x\n", rtc_readl(pxa_rtc, RTTR));
	seq_printf(seq, "update_IRQ\t: %s\n",
		   (rtc_readl(pxa_rtc, RTSR) & RTSR_HZE) ? "yes" : "no");
	seq_printf(seq, "periodic_IRQ\t: %s\n",
		   (rtc_readl(pxa_rtc, RTSR) & RTSR_PIALE) ? "yes" : "no");
	seq_printf(seq, "periodic_freq\t: %u\n", rtc_readl(pxa_rtc, PIAR));

	return 0;
}

static const struct rtc_class_ops pxa_rtc_ops = {
	.open = pxa_rtc_open,
	.release = pxa_rtc_release,
	.ioctl = pxa_rtc_ioctl,
	.read_time = pxa_rtc_read_time,
	.set_time = pxa_rtc_set_time,
	.read_alarm = pxa_rtc_read_alarm,
	.set_alarm = pxa_rtc_set_alarm,
	.proc = pxa_rtc_proc,
	.irq_set_state = pxa_periodic_irq_set_state,
	.irq_set_freq = pxa_periodic_irq_set_freq,
};

static int __init pxa_rtc_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct pxa_rtc *pxa_rtc;
	int ret;
	u32 rttr;

	pxa_rtc = kzalloc(sizeof(struct pxa_rtc), GFP_KERNEL);
	if (!pxa_rtc)
		return -ENOMEM;

	spin_lock_init(&pxa_rtc->lock);
	platform_set_drvdata(pdev, pxa_rtc);

	ret = -ENXIO;
	pxa_rtc->ress = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!pxa_rtc->ress) {
		dev_err(dev, "No I/O memory resource defined\n");
		goto err_ress;
	}

	pxa_rtc->irq_1Hz = platform_get_irq(pdev, 0);
	if (pxa_rtc->irq_1Hz < 0) {
		dev_err(dev, "No 1Hz IRQ resource defined\n");
		goto err_ress;
	}
	pxa_rtc->irq_Alrm = platform_get_irq(pdev, 1);
	if (pxa_rtc->irq_Alrm < 0) {
		dev_err(dev, "No alarm IRQ resource defined\n");
		goto err_ress;
	}

	ret = -ENOMEM;
	pxa_rtc->base = ioremap(pxa_rtc->ress->start,
				resource_size(pxa_rtc->ress));
	if (!pxa_rtc->base) {
		dev_err(&pdev->dev, "Unable to map pxa RTC I/O memory\n");
		goto err_map;
	}

	/*
	 * If the clock divider is uninitialized then reset it to the
	 * default value to get the 1Hz clock.
	 */
	if (rtc_readl(pxa_rtc, RTTR) == 0) {
		rttr = RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16);
		rtc_writel(pxa_rtc, RTTR, rttr);
		dev_warn(dev, "warning: initializing default clock"
			 " divider/trim value\n");
	}

	rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);

	pxa_rtc->rtc = rtc_device_register("pxa-rtc", &pdev->dev, &pxa_rtc_ops,
					   THIS_MODULE);
	ret = PTR_ERR(pxa_rtc->rtc);
	if (IS_ERR(pxa_rtc->rtc)) {
		dev_err(dev, "Failed to register RTC device -> %d\n", ret);
		goto err_rtc_reg;
	}

	device_init_wakeup(dev, 1);

	return 0;

err_rtc_reg:
	 iounmap(pxa_rtc->base);
err_ress:
err_map:
	kfree(pxa_rtc);
	return ret;
}

static int __exit pxa_rtc_remove(struct platform_device *pdev)
{
	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);

	rtc_device_unregister(pxa_rtc->rtc);

	spin_lock_irq(&pxa_rtc->lock);
	iounmap(pxa_rtc->base);
	spin_unlock_irq(&pxa_rtc->lock);

	kfree(pxa_rtc);

	return 0;
}

#ifdef CONFIG_PM
static int pxa_rtc_suspend(struct device *dev)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

	if (device_may_wakeup(dev))
		enable_irq_wake(pxa_rtc->irq_Alrm);
	return 0;
}

static int pxa_rtc_resume(struct device *dev)
{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

	if (device_may_wakeup(dev))
		disable_irq_wake(pxa_rtc->irq_Alrm);
	return 0;
}

static const struct dev_pm_ops pxa_rtc_pm_ops = {
	.suspend	= pxa_rtc_suspend,
	.resume		= pxa_rtc_resume,
};
#endif

static struct platform_driver pxa_rtc_driver = {
	.remove		= __exit_p(pxa_rtc_remove),
	.driver		= {
		.name	= "pxa-rtc",
#ifdef CONFIG_PM
		.pm	= &pxa_rtc_pm_ops,
#endif
	},
};

static int __init pxa_rtc_init(void)
{
	if (cpu_is_pxa27x() || cpu_is_pxa3xx())
		return platform_driver_probe(&pxa_rtc_driver, pxa_rtc_probe);

	return -ENODEV;
}

static void __exit pxa_rtc_exit(void)
{
	platform_driver_unregister(&pxa_rtc_driver);
}

module_init(pxa_rtc_init);
module_exit(pxa_rtc_exit);

MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pxa-rtc");