xref: /openbmc/linux/drivers/rtc/rtc-pxa.c (revision ae213c44)
1 /*
2  * Real Time Clock interface for XScale PXA27x and PXA3xx
3  *
4  * Copyright (C) 2008 Robert Jarzmik
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  *
20  */
21 
22 #include <linux/init.h>
23 #include <linux/platform_device.h>
24 #include <linux/module.h>
25 #include <linux/rtc.h>
26 #include <linux/seq_file.h>
27 #include <linux/interrupt.h>
28 #include <linux/io.h>
29 #include <linux/slab.h>
30 #include <linux/of.h>
31 #include <linux/of_device.h>
32 
33 #include <mach/hardware.h>
34 
35 #include "rtc-sa1100.h"
36 
37 #define RTC_DEF_DIVIDER		(32768 - 1)
38 #define RTC_DEF_TRIM		0
39 #define MAXFREQ_PERIODIC	1000
40 
41 /*
42  * PXA Registers and bits definitions
43  */
44 #define RTSR_PICE	(1 << 15)	/* Periodic interrupt count enable */
45 #define RTSR_PIALE	(1 << 14)	/* Periodic interrupt Alarm enable */
46 #define RTSR_PIAL	(1 << 13)	/* Periodic interrupt detected */
47 #define RTSR_SWALE2	(1 << 11)	/* RTC stopwatch alarm2 enable */
48 #define RTSR_SWAL2	(1 << 10)	/* RTC stopwatch alarm2 detected */
49 #define RTSR_SWALE1	(1 << 9)	/* RTC stopwatch alarm1 enable */
50 #define RTSR_SWAL1	(1 << 8)	/* RTC stopwatch alarm1 detected */
51 #define RTSR_RDALE2	(1 << 7)	/* RTC alarm2 enable */
52 #define RTSR_RDAL2	(1 << 6)	/* RTC alarm2 detected */
53 #define RTSR_RDALE1	(1 << 5)	/* RTC alarm1 enable */
54 #define RTSR_RDAL1	(1 << 4)	/* RTC alarm1 detected */
55 #define RTSR_HZE	(1 << 3)	/* HZ interrupt enable */
56 #define RTSR_ALE	(1 << 2)	/* RTC alarm interrupt enable */
57 #define RTSR_HZ		(1 << 1)	/* HZ rising-edge detected */
58 #define RTSR_AL		(1 << 0)	/* RTC alarm detected */
59 #define RTSR_TRIG_MASK	(RTSR_AL | RTSR_HZ | RTSR_RDAL1 | RTSR_RDAL2\
60 			 | RTSR_SWAL1 | RTSR_SWAL2)
61 #define RYxR_YEAR_S	9
62 #define RYxR_YEAR_MASK	(0xfff << RYxR_YEAR_S)
63 #define RYxR_MONTH_S	5
64 #define RYxR_MONTH_MASK	(0xf << RYxR_MONTH_S)
65 #define RYxR_DAY_MASK	0x1f
66 #define RDxR_WOM_S     20
67 #define RDxR_WOM_MASK  (0x7 << RDxR_WOM_S)
68 #define RDxR_DOW_S     17
69 #define RDxR_DOW_MASK  (0x7 << RDxR_DOW_S)
70 #define RDxR_HOUR_S	12
71 #define RDxR_HOUR_MASK	(0x1f << RDxR_HOUR_S)
72 #define RDxR_MIN_S	6
73 #define RDxR_MIN_MASK	(0x3f << RDxR_MIN_S)
74 #define RDxR_SEC_MASK	0x3f
75 
76 #define RTSR		0x08
77 #define RTTR		0x0c
78 #define RDCR		0x10
79 #define RYCR		0x14
80 #define RDAR1		0x18
81 #define RYAR1		0x1c
82 #define RTCPICR		0x34
83 #define PIAR		0x38
84 
85 #define rtc_readl(pxa_rtc, reg)	\
86 	__raw_readl((pxa_rtc)->base + (reg))
87 #define rtc_writel(pxa_rtc, reg, value)	\
88 	__raw_writel((value), (pxa_rtc)->base + (reg))
89 
90 struct pxa_rtc {
91 	struct sa1100_rtc sa1100_rtc;
92 	struct resource	*ress;
93 	void __iomem		*base;
94 	struct rtc_device	*rtc;
95 	spinlock_t		lock;		/* Protects this structure */
96 };
97 
98 
99 static u32 ryxr_calc(struct rtc_time *tm)
100 {
101 	return ((tm->tm_year + 1900) << RYxR_YEAR_S)
102 		| ((tm->tm_mon + 1) << RYxR_MONTH_S)
103 		| tm->tm_mday;
104 }
105 
106 static u32 rdxr_calc(struct rtc_time *tm)
107 {
108 	return ((((tm->tm_mday + 6) / 7) << RDxR_WOM_S) & RDxR_WOM_MASK)
109 		| (((tm->tm_wday + 1) << RDxR_DOW_S) & RDxR_DOW_MASK)
110 		| (tm->tm_hour << RDxR_HOUR_S)
111 		| (tm->tm_min << RDxR_MIN_S)
112 		| tm->tm_sec;
113 }
114 
115 static void tm_calc(u32 rycr, u32 rdcr, struct rtc_time *tm)
116 {
117 	tm->tm_year = ((rycr & RYxR_YEAR_MASK) >> RYxR_YEAR_S) - 1900;
118 	tm->tm_mon = (((rycr & RYxR_MONTH_MASK) >> RYxR_MONTH_S)) - 1;
119 	tm->tm_mday = (rycr & RYxR_DAY_MASK);
120 	tm->tm_wday = ((rycr & RDxR_DOW_MASK) >> RDxR_DOW_S) - 1;
121 	tm->tm_hour = (rdcr & RDxR_HOUR_MASK) >> RDxR_HOUR_S;
122 	tm->tm_min = (rdcr & RDxR_MIN_MASK) >> RDxR_MIN_S;
123 	tm->tm_sec = rdcr & RDxR_SEC_MASK;
124 }
125 
126 static void rtsr_clear_bits(struct pxa_rtc *pxa_rtc, u32 mask)
127 {
128 	u32 rtsr;
129 
130 	rtsr = rtc_readl(pxa_rtc, RTSR);
131 	rtsr &= ~RTSR_TRIG_MASK;
132 	rtsr &= ~mask;
133 	rtc_writel(pxa_rtc, RTSR, rtsr);
134 }
135 
136 static void rtsr_set_bits(struct pxa_rtc *pxa_rtc, u32 mask)
137 {
138 	u32 rtsr;
139 
140 	rtsr = rtc_readl(pxa_rtc, RTSR);
141 	rtsr &= ~RTSR_TRIG_MASK;
142 	rtsr |= mask;
143 	rtc_writel(pxa_rtc, RTSR, rtsr);
144 }
145 
146 static irqreturn_t pxa_rtc_irq(int irq, void *dev_id)
147 {
148 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev_id);
149 	u32 rtsr;
150 	unsigned long events = 0;
151 
152 	spin_lock(&pxa_rtc->lock);
153 
154 	/* clear interrupt sources */
155 	rtsr = rtc_readl(pxa_rtc, RTSR);
156 	rtc_writel(pxa_rtc, RTSR, rtsr);
157 
158 	/* temporary disable rtc interrupts */
159 	rtsr_clear_bits(pxa_rtc, RTSR_RDALE1 | RTSR_PIALE | RTSR_HZE);
160 
161 	/* clear alarm interrupt if it has occurred */
162 	if (rtsr & RTSR_RDAL1)
163 		rtsr &= ~RTSR_RDALE1;
164 
165 	/* update irq data & counter */
166 	if (rtsr & RTSR_RDAL1)
167 		events |= RTC_AF | RTC_IRQF;
168 	if (rtsr & RTSR_HZ)
169 		events |= RTC_UF | RTC_IRQF;
170 	if (rtsr & RTSR_PIAL)
171 		events |= RTC_PF | RTC_IRQF;
172 
173 	rtc_update_irq(pxa_rtc->rtc, 1, events);
174 
175 	/* enable back rtc interrupts */
176 	rtc_writel(pxa_rtc, RTSR, rtsr & ~RTSR_TRIG_MASK);
177 
178 	spin_unlock(&pxa_rtc->lock);
179 	return IRQ_HANDLED;
180 }
181 
182 static int pxa_rtc_open(struct device *dev)
183 {
184 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
185 	int ret;
186 
187 	ret = request_irq(pxa_rtc->sa1100_rtc.irq_1hz, pxa_rtc_irq, 0,
188 			  "rtc 1Hz", dev);
189 	if (ret < 0) {
190 		dev_err(dev, "can't get irq %i, err %d\n",
191 			pxa_rtc->sa1100_rtc.irq_1hz, ret);
192 		goto err_irq_1Hz;
193 	}
194 	ret = request_irq(pxa_rtc->sa1100_rtc.irq_alarm, pxa_rtc_irq, 0,
195 			  "rtc Alrm", dev);
196 	if (ret < 0) {
197 		dev_err(dev, "can't get irq %i, err %d\n",
198 			pxa_rtc->sa1100_rtc.irq_alarm, ret);
199 		goto err_irq_Alrm;
200 	}
201 
202 	return 0;
203 
204 err_irq_Alrm:
205 	free_irq(pxa_rtc->sa1100_rtc.irq_1hz, dev);
206 err_irq_1Hz:
207 	return ret;
208 }
209 
210 static void pxa_rtc_release(struct device *dev)
211 {
212 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
213 
214 	spin_lock_irq(&pxa_rtc->lock);
215 	rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
216 	spin_unlock_irq(&pxa_rtc->lock);
217 
218 	free_irq(pxa_rtc->sa1100_rtc.irq_1hz, dev);
219 	free_irq(pxa_rtc->sa1100_rtc.irq_alarm, dev);
220 }
221 
222 static int pxa_alarm_irq_enable(struct device *dev, unsigned int enabled)
223 {
224 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
225 
226 	spin_lock_irq(&pxa_rtc->lock);
227 
228 	if (enabled)
229 		rtsr_set_bits(pxa_rtc, RTSR_RDALE1);
230 	else
231 		rtsr_clear_bits(pxa_rtc, RTSR_RDALE1);
232 
233 	spin_unlock_irq(&pxa_rtc->lock);
234 	return 0;
235 }
236 
237 static int pxa_rtc_read_time(struct device *dev, struct rtc_time *tm)
238 {
239 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
240 	u32 rycr, rdcr;
241 
242 	rycr = rtc_readl(pxa_rtc, RYCR);
243 	rdcr = rtc_readl(pxa_rtc, RDCR);
244 
245 	tm_calc(rycr, rdcr, tm);
246 	return 0;
247 }
248 
249 static int pxa_rtc_set_time(struct device *dev, struct rtc_time *tm)
250 {
251 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
252 
253 	rtc_writel(pxa_rtc, RYCR, ryxr_calc(tm));
254 	rtc_writel(pxa_rtc, RDCR, rdxr_calc(tm));
255 
256 	return 0;
257 }
258 
259 static int pxa_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
260 {
261 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
262 	u32 rtsr, ryar, rdar;
263 
264 	ryar = rtc_readl(pxa_rtc, RYAR1);
265 	rdar = rtc_readl(pxa_rtc, RDAR1);
266 	tm_calc(ryar, rdar, &alrm->time);
267 
268 	rtsr = rtc_readl(pxa_rtc, RTSR);
269 	alrm->enabled = (rtsr & RTSR_RDALE1) ? 1 : 0;
270 	alrm->pending = (rtsr & RTSR_RDAL1) ? 1 : 0;
271 	return 0;
272 }
273 
274 static int pxa_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
275 {
276 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
277 	u32 rtsr;
278 
279 	spin_lock_irq(&pxa_rtc->lock);
280 
281 	rtc_writel(pxa_rtc, RYAR1, ryxr_calc(&alrm->time));
282 	rtc_writel(pxa_rtc, RDAR1, rdxr_calc(&alrm->time));
283 
284 	rtsr = rtc_readl(pxa_rtc, RTSR);
285 	if (alrm->enabled)
286 		rtsr |= RTSR_RDALE1;
287 	else
288 		rtsr &= ~RTSR_RDALE1;
289 	rtc_writel(pxa_rtc, RTSR, rtsr);
290 
291 	spin_unlock_irq(&pxa_rtc->lock);
292 
293 	return 0;
294 }
295 
296 static int pxa_rtc_proc(struct device *dev, struct seq_file *seq)
297 {
298 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
299 
300 	seq_printf(seq, "trim/divider\t: 0x%08x\n", rtc_readl(pxa_rtc, RTTR));
301 	seq_printf(seq, "update_IRQ\t: %s\n",
302 		   (rtc_readl(pxa_rtc, RTSR) & RTSR_HZE) ? "yes" : "no");
303 	seq_printf(seq, "periodic_IRQ\t: %s\n",
304 		   (rtc_readl(pxa_rtc, RTSR) & RTSR_PIALE) ? "yes" : "no");
305 	seq_printf(seq, "periodic_freq\t: %u\n", rtc_readl(pxa_rtc, PIAR));
306 
307 	return 0;
308 }
309 
310 static const struct rtc_class_ops pxa_rtc_ops = {
311 	.read_time = pxa_rtc_read_time,
312 	.set_time = pxa_rtc_set_time,
313 	.read_alarm = pxa_rtc_read_alarm,
314 	.set_alarm = pxa_rtc_set_alarm,
315 	.alarm_irq_enable = pxa_alarm_irq_enable,
316 	.proc = pxa_rtc_proc,
317 };
318 
319 static int __init pxa_rtc_probe(struct platform_device *pdev)
320 {
321 	struct device *dev = &pdev->dev;
322 	struct pxa_rtc *pxa_rtc;
323 	struct sa1100_rtc *sa1100_rtc;
324 	int ret;
325 
326 	pxa_rtc = devm_kzalloc(dev, sizeof(*pxa_rtc), GFP_KERNEL);
327 	if (!pxa_rtc)
328 		return -ENOMEM;
329 	sa1100_rtc = &pxa_rtc->sa1100_rtc;
330 
331 	spin_lock_init(&pxa_rtc->lock);
332 	platform_set_drvdata(pdev, pxa_rtc);
333 
334 	pxa_rtc->ress = platform_get_resource(pdev, IORESOURCE_MEM, 0);
335 	if (!pxa_rtc->ress) {
336 		dev_err(dev, "No I/O memory resource defined\n");
337 		return -ENXIO;
338 	}
339 
340 	sa1100_rtc->irq_1hz = platform_get_irq(pdev, 0);
341 	if (sa1100_rtc->irq_1hz < 0) {
342 		dev_err(dev, "No 1Hz IRQ resource defined\n");
343 		return -ENXIO;
344 	}
345 	sa1100_rtc->irq_alarm = platform_get_irq(pdev, 1);
346 	if (sa1100_rtc->irq_alarm < 0) {
347 		dev_err(dev, "No alarm IRQ resource defined\n");
348 		return -ENXIO;
349 	}
350 
351 	pxa_rtc->base = devm_ioremap(dev, pxa_rtc->ress->start,
352 				resource_size(pxa_rtc->ress));
353 	if (!pxa_rtc->base) {
354 		dev_err(dev, "Unable to map pxa RTC I/O memory\n");
355 		return -ENOMEM;
356 	}
357 
358 	pxa_rtc_open(dev);
359 
360 	sa1100_rtc->rcnr = pxa_rtc->base + 0x0;
361 	sa1100_rtc->rtsr = pxa_rtc->base + 0x8;
362 	sa1100_rtc->rtar = pxa_rtc->base + 0x4;
363 	sa1100_rtc->rttr = pxa_rtc->base + 0xc;
364 	ret = sa1100_rtc_init(pdev, sa1100_rtc);
365 	if (ret) {
366 		dev_err(dev, "Unable to init SA1100 RTC sub-device\n");
367 		return ret;
368 	}
369 
370 	rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
371 
372 	pxa_rtc->rtc = devm_rtc_device_register(&pdev->dev, "pxa-rtc",
373 						&pxa_rtc_ops, THIS_MODULE);
374 	if (IS_ERR(pxa_rtc->rtc)) {
375 		ret = PTR_ERR(pxa_rtc->rtc);
376 		dev_err(dev, "Failed to register RTC device -> %d\n", ret);
377 		return ret;
378 	}
379 
380 	device_init_wakeup(dev, 1);
381 
382 	return 0;
383 }
384 
385 static int __exit pxa_rtc_remove(struct platform_device *pdev)
386 {
387 	struct device *dev = &pdev->dev;
388 
389 	pxa_rtc_release(dev);
390 	return 0;
391 }
392 
393 #ifdef CONFIG_OF
394 static const struct of_device_id pxa_rtc_dt_ids[] = {
395 	{ .compatible = "marvell,pxa-rtc" },
396 	{}
397 };
398 MODULE_DEVICE_TABLE(of, pxa_rtc_dt_ids);
399 #endif
400 
401 #ifdef CONFIG_PM_SLEEP
402 static int pxa_rtc_suspend(struct device *dev)
403 {
404 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
405 
406 	if (device_may_wakeup(dev))
407 		enable_irq_wake(pxa_rtc->sa1100_rtc.irq_alarm);
408 	return 0;
409 }
410 
411 static int pxa_rtc_resume(struct device *dev)
412 {
413 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
414 
415 	if (device_may_wakeup(dev))
416 		disable_irq_wake(pxa_rtc->sa1100_rtc.irq_alarm);
417 	return 0;
418 }
419 #endif
420 
421 static SIMPLE_DEV_PM_OPS(pxa_rtc_pm_ops, pxa_rtc_suspend, pxa_rtc_resume);
422 
423 static struct platform_driver pxa_rtc_driver = {
424 	.remove		= __exit_p(pxa_rtc_remove),
425 	.driver		= {
426 		.name	= "pxa-rtc",
427 		.of_match_table = of_match_ptr(pxa_rtc_dt_ids),
428 		.pm	= &pxa_rtc_pm_ops,
429 	},
430 };
431 
432 module_platform_driver_probe(pxa_rtc_driver, pxa_rtc_probe);
433 
434 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
435 MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)");
436 MODULE_LICENSE("GPL");
437 MODULE_ALIAS("platform:pxa-rtc");
438