xref: /linux/drivers/rtc/rtc-pxa.c (revision 1fe3a33ba0a37e7aa0df0acbe31d5dda7610c16e)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Real Time Clock interface for XScale PXA27x and PXA3xx
4  *
5  * Copyright (C) 2008 Robert Jarzmik
6  */
7 
8 #include <linux/init.h>
9 #include <linux/platform_device.h>
10 #include <linux/module.h>
11 #include <linux/rtc.h>
12 #include <linux/seq_file.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/slab.h>
16 #include <linux/of.h>
17 #include <linux/of_device.h>
18 
19 #include <mach/hardware.h>
20 
21 #include "rtc-sa1100.h"
22 
23 #define RTC_DEF_DIVIDER		(32768 - 1)
24 #define RTC_DEF_TRIM		0
25 #define MAXFREQ_PERIODIC	1000
26 
27 /*
28  * PXA Registers and bits definitions
29  */
30 #define RTSR_PICE	(1 << 15)	/* Periodic interrupt count enable */
31 #define RTSR_PIALE	(1 << 14)	/* Periodic interrupt Alarm enable */
32 #define RTSR_PIAL	(1 << 13)	/* Periodic interrupt detected */
33 #define RTSR_SWALE2	(1 << 11)	/* RTC stopwatch alarm2 enable */
34 #define RTSR_SWAL2	(1 << 10)	/* RTC stopwatch alarm2 detected */
35 #define RTSR_SWALE1	(1 << 9)	/* RTC stopwatch alarm1 enable */
36 #define RTSR_SWAL1	(1 << 8)	/* RTC stopwatch alarm1 detected */
37 #define RTSR_RDALE2	(1 << 7)	/* RTC alarm2 enable */
38 #define RTSR_RDAL2	(1 << 6)	/* RTC alarm2 detected */
39 #define RTSR_RDALE1	(1 << 5)	/* RTC alarm1 enable */
40 #define RTSR_RDAL1	(1 << 4)	/* RTC alarm1 detected */
41 #define RTSR_HZE	(1 << 3)	/* HZ interrupt enable */
42 #define RTSR_ALE	(1 << 2)	/* RTC alarm interrupt enable */
43 #define RTSR_HZ		(1 << 1)	/* HZ rising-edge detected */
44 #define RTSR_AL		(1 << 0)	/* RTC alarm detected */
45 #define RTSR_TRIG_MASK	(RTSR_AL | RTSR_HZ | RTSR_RDAL1 | RTSR_RDAL2\
46 			 | RTSR_SWAL1 | RTSR_SWAL2)
47 #define RYxR_YEAR_S	9
48 #define RYxR_YEAR_MASK	(0xfff << RYxR_YEAR_S)
49 #define RYxR_MONTH_S	5
50 #define RYxR_MONTH_MASK	(0xf << RYxR_MONTH_S)
51 #define RYxR_DAY_MASK	0x1f
52 #define RDxR_WOM_S     20
53 #define RDxR_WOM_MASK  (0x7 << RDxR_WOM_S)
54 #define RDxR_DOW_S     17
55 #define RDxR_DOW_MASK  (0x7 << RDxR_DOW_S)
56 #define RDxR_HOUR_S	12
57 #define RDxR_HOUR_MASK	(0x1f << RDxR_HOUR_S)
58 #define RDxR_MIN_S	6
59 #define RDxR_MIN_MASK	(0x3f << RDxR_MIN_S)
60 #define RDxR_SEC_MASK	0x3f
61 
62 #define RTSR		0x08
63 #define RTTR		0x0c
64 #define RDCR		0x10
65 #define RYCR		0x14
66 #define RDAR1		0x18
67 #define RYAR1		0x1c
68 #define RTCPICR		0x34
69 #define PIAR		0x38
70 
71 #define rtc_readl(pxa_rtc, reg)	\
72 	__raw_readl((pxa_rtc)->base + (reg))
73 #define rtc_writel(pxa_rtc, reg, value)	\
74 	__raw_writel((value), (pxa_rtc)->base + (reg))
75 
76 struct pxa_rtc {
77 	struct sa1100_rtc sa1100_rtc;
78 	struct resource	*ress;
79 	void __iomem		*base;
80 	struct rtc_device	*rtc;
81 	spinlock_t		lock;		/* Protects this structure */
82 };
83 
84 
85 static u32 ryxr_calc(struct rtc_time *tm)
86 {
87 	return ((tm->tm_year + 1900) << RYxR_YEAR_S)
88 		| ((tm->tm_mon + 1) << RYxR_MONTH_S)
89 		| tm->tm_mday;
90 }
91 
92 static u32 rdxr_calc(struct rtc_time *tm)
93 {
94 	return ((((tm->tm_mday + 6) / 7) << RDxR_WOM_S) & RDxR_WOM_MASK)
95 		| (((tm->tm_wday + 1) << RDxR_DOW_S) & RDxR_DOW_MASK)
96 		| (tm->tm_hour << RDxR_HOUR_S)
97 		| (tm->tm_min << RDxR_MIN_S)
98 		| tm->tm_sec;
99 }
100 
101 static void tm_calc(u32 rycr, u32 rdcr, struct rtc_time *tm)
102 {
103 	tm->tm_year = ((rycr & RYxR_YEAR_MASK) >> RYxR_YEAR_S) - 1900;
104 	tm->tm_mon = (((rycr & RYxR_MONTH_MASK) >> RYxR_MONTH_S)) - 1;
105 	tm->tm_mday = (rycr & RYxR_DAY_MASK);
106 	tm->tm_wday = ((rycr & RDxR_DOW_MASK) >> RDxR_DOW_S) - 1;
107 	tm->tm_hour = (rdcr & RDxR_HOUR_MASK) >> RDxR_HOUR_S;
108 	tm->tm_min = (rdcr & RDxR_MIN_MASK) >> RDxR_MIN_S;
109 	tm->tm_sec = rdcr & RDxR_SEC_MASK;
110 }
111 
112 static void rtsr_clear_bits(struct pxa_rtc *pxa_rtc, u32 mask)
113 {
114 	u32 rtsr;
115 
116 	rtsr = rtc_readl(pxa_rtc, RTSR);
117 	rtsr &= ~RTSR_TRIG_MASK;
118 	rtsr &= ~mask;
119 	rtc_writel(pxa_rtc, RTSR, rtsr);
120 }
121 
122 static void rtsr_set_bits(struct pxa_rtc *pxa_rtc, u32 mask)
123 {
124 	u32 rtsr;
125 
126 	rtsr = rtc_readl(pxa_rtc, RTSR);
127 	rtsr &= ~RTSR_TRIG_MASK;
128 	rtsr |= mask;
129 	rtc_writel(pxa_rtc, RTSR, rtsr);
130 }
131 
132 static irqreturn_t pxa_rtc_irq(int irq, void *dev_id)
133 {
134 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev_id);
135 	u32 rtsr;
136 	unsigned long events = 0;
137 
138 	spin_lock(&pxa_rtc->lock);
139 
140 	/* clear interrupt sources */
141 	rtsr = rtc_readl(pxa_rtc, RTSR);
142 	rtc_writel(pxa_rtc, RTSR, rtsr);
143 
144 	/* temporary disable rtc interrupts */
145 	rtsr_clear_bits(pxa_rtc, RTSR_RDALE1 | RTSR_PIALE | RTSR_HZE);
146 
147 	/* clear alarm interrupt if it has occurred */
148 	if (rtsr & RTSR_RDAL1)
149 		rtsr &= ~RTSR_RDALE1;
150 
151 	/* update irq data & counter */
152 	if (rtsr & RTSR_RDAL1)
153 		events |= RTC_AF | RTC_IRQF;
154 	if (rtsr & RTSR_HZ)
155 		events |= RTC_UF | RTC_IRQF;
156 	if (rtsr & RTSR_PIAL)
157 		events |= RTC_PF | RTC_IRQF;
158 
159 	rtc_update_irq(pxa_rtc->rtc, 1, events);
160 
161 	/* enable back rtc interrupts */
162 	rtc_writel(pxa_rtc, RTSR, rtsr & ~RTSR_TRIG_MASK);
163 
164 	spin_unlock(&pxa_rtc->lock);
165 	return IRQ_HANDLED;
166 }
167 
168 static int pxa_rtc_open(struct device *dev)
169 {
170 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
171 	int ret;
172 
173 	ret = request_irq(pxa_rtc->sa1100_rtc.irq_1hz, pxa_rtc_irq, 0,
174 			  "rtc 1Hz", dev);
175 	if (ret < 0) {
176 		dev_err(dev, "can't get irq %i, err %d\n",
177 			pxa_rtc->sa1100_rtc.irq_1hz, ret);
178 		goto err_irq_1Hz;
179 	}
180 	ret = request_irq(pxa_rtc->sa1100_rtc.irq_alarm, pxa_rtc_irq, 0,
181 			  "rtc Alrm", dev);
182 	if (ret < 0) {
183 		dev_err(dev, "can't get irq %i, err %d\n",
184 			pxa_rtc->sa1100_rtc.irq_alarm, ret);
185 		goto err_irq_Alrm;
186 	}
187 
188 	return 0;
189 
190 err_irq_Alrm:
191 	free_irq(pxa_rtc->sa1100_rtc.irq_1hz, dev);
192 err_irq_1Hz:
193 	return ret;
194 }
195 
196 static void pxa_rtc_release(struct device *dev)
197 {
198 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
199 
200 	spin_lock_irq(&pxa_rtc->lock);
201 	rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
202 	spin_unlock_irq(&pxa_rtc->lock);
203 
204 	free_irq(pxa_rtc->sa1100_rtc.irq_1hz, dev);
205 	free_irq(pxa_rtc->sa1100_rtc.irq_alarm, dev);
206 }
207 
208 static int pxa_alarm_irq_enable(struct device *dev, unsigned int enabled)
209 {
210 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
211 
212 	spin_lock_irq(&pxa_rtc->lock);
213 
214 	if (enabled)
215 		rtsr_set_bits(pxa_rtc, RTSR_RDALE1);
216 	else
217 		rtsr_clear_bits(pxa_rtc, RTSR_RDALE1);
218 
219 	spin_unlock_irq(&pxa_rtc->lock);
220 	return 0;
221 }
222 
223 static int pxa_rtc_read_time(struct device *dev, struct rtc_time *tm)
224 {
225 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
226 	u32 rycr, rdcr;
227 
228 	rycr = rtc_readl(pxa_rtc, RYCR);
229 	rdcr = rtc_readl(pxa_rtc, RDCR);
230 
231 	tm_calc(rycr, rdcr, tm);
232 	return 0;
233 }
234 
235 static int pxa_rtc_set_time(struct device *dev, struct rtc_time *tm)
236 {
237 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
238 
239 	rtc_writel(pxa_rtc, RYCR, ryxr_calc(tm));
240 	rtc_writel(pxa_rtc, RDCR, rdxr_calc(tm));
241 
242 	return 0;
243 }
244 
245 static int pxa_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
246 {
247 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
248 	u32 rtsr, ryar, rdar;
249 
250 	ryar = rtc_readl(pxa_rtc, RYAR1);
251 	rdar = rtc_readl(pxa_rtc, RDAR1);
252 	tm_calc(ryar, rdar, &alrm->time);
253 
254 	rtsr = rtc_readl(pxa_rtc, RTSR);
255 	alrm->enabled = (rtsr & RTSR_RDALE1) ? 1 : 0;
256 	alrm->pending = (rtsr & RTSR_RDAL1) ? 1 : 0;
257 	return 0;
258 }
259 
260 static int pxa_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
261 {
262 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
263 	u32 rtsr;
264 
265 	spin_lock_irq(&pxa_rtc->lock);
266 
267 	rtc_writel(pxa_rtc, RYAR1, ryxr_calc(&alrm->time));
268 	rtc_writel(pxa_rtc, RDAR1, rdxr_calc(&alrm->time));
269 
270 	rtsr = rtc_readl(pxa_rtc, RTSR);
271 	if (alrm->enabled)
272 		rtsr |= RTSR_RDALE1;
273 	else
274 		rtsr &= ~RTSR_RDALE1;
275 	rtc_writel(pxa_rtc, RTSR, rtsr);
276 
277 	spin_unlock_irq(&pxa_rtc->lock);
278 
279 	return 0;
280 }
281 
282 static int pxa_rtc_proc(struct device *dev, struct seq_file *seq)
283 {
284 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
285 
286 	seq_printf(seq, "trim/divider\t: 0x%08x\n", rtc_readl(pxa_rtc, RTTR));
287 	seq_printf(seq, "update_IRQ\t: %s\n",
288 		   (rtc_readl(pxa_rtc, RTSR) & RTSR_HZE) ? "yes" : "no");
289 	seq_printf(seq, "periodic_IRQ\t: %s\n",
290 		   (rtc_readl(pxa_rtc, RTSR) & RTSR_PIALE) ? "yes" : "no");
291 	seq_printf(seq, "periodic_freq\t: %u\n", rtc_readl(pxa_rtc, PIAR));
292 
293 	return 0;
294 }
295 
296 static const struct rtc_class_ops pxa_rtc_ops = {
297 	.read_time = pxa_rtc_read_time,
298 	.set_time = pxa_rtc_set_time,
299 	.read_alarm = pxa_rtc_read_alarm,
300 	.set_alarm = pxa_rtc_set_alarm,
301 	.alarm_irq_enable = pxa_alarm_irq_enable,
302 	.proc = pxa_rtc_proc,
303 };
304 
305 static int __init pxa_rtc_probe(struct platform_device *pdev)
306 {
307 	struct device *dev = &pdev->dev;
308 	struct pxa_rtc *pxa_rtc;
309 	struct sa1100_rtc *sa1100_rtc;
310 	int ret;
311 
312 	pxa_rtc = devm_kzalloc(dev, sizeof(*pxa_rtc), GFP_KERNEL);
313 	if (!pxa_rtc)
314 		return -ENOMEM;
315 	sa1100_rtc = &pxa_rtc->sa1100_rtc;
316 
317 	spin_lock_init(&pxa_rtc->lock);
318 	platform_set_drvdata(pdev, pxa_rtc);
319 
320 	pxa_rtc->ress = platform_get_resource(pdev, IORESOURCE_MEM, 0);
321 	if (!pxa_rtc->ress) {
322 		dev_err(dev, "No I/O memory resource defined\n");
323 		return -ENXIO;
324 	}
325 
326 	sa1100_rtc->irq_1hz = platform_get_irq(pdev, 0);
327 	if (sa1100_rtc->irq_1hz < 0)
328 		return -ENXIO;
329 	sa1100_rtc->irq_alarm = platform_get_irq(pdev, 1);
330 	if (sa1100_rtc->irq_alarm < 0)
331 		return -ENXIO;
332 
333 	sa1100_rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
334 	if (IS_ERR(sa1100_rtc->rtc))
335 		return PTR_ERR(sa1100_rtc->rtc);
336 
337 	pxa_rtc->base = devm_ioremap(dev, pxa_rtc->ress->start,
338 				resource_size(pxa_rtc->ress));
339 	if (!pxa_rtc->base) {
340 		dev_err(dev, "Unable to map pxa RTC I/O memory\n");
341 		return -ENOMEM;
342 	}
343 
344 	pxa_rtc_open(dev);
345 
346 	sa1100_rtc->rcnr = pxa_rtc->base + 0x0;
347 	sa1100_rtc->rtsr = pxa_rtc->base + 0x8;
348 	sa1100_rtc->rtar = pxa_rtc->base + 0x4;
349 	sa1100_rtc->rttr = pxa_rtc->base + 0xc;
350 	ret = sa1100_rtc_init(pdev, sa1100_rtc);
351 	if (ret) {
352 		dev_err(dev, "Unable to init SA1100 RTC sub-device\n");
353 		return ret;
354 	}
355 
356 	rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
357 
358 	pxa_rtc->rtc = devm_rtc_device_register(&pdev->dev, "pxa-rtc",
359 						&pxa_rtc_ops, THIS_MODULE);
360 	if (IS_ERR(pxa_rtc->rtc)) {
361 		ret = PTR_ERR(pxa_rtc->rtc);
362 		dev_err(dev, "Failed to register RTC device -> %d\n", ret);
363 		return ret;
364 	}
365 
366 	device_init_wakeup(dev, 1);
367 
368 	return 0;
369 }
370 
371 static int __exit pxa_rtc_remove(struct platform_device *pdev)
372 {
373 	struct device *dev = &pdev->dev;
374 
375 	pxa_rtc_release(dev);
376 	return 0;
377 }
378 
379 #ifdef CONFIG_OF
380 static const struct of_device_id pxa_rtc_dt_ids[] = {
381 	{ .compatible = "marvell,pxa-rtc" },
382 	{}
383 };
384 MODULE_DEVICE_TABLE(of, pxa_rtc_dt_ids);
385 #endif
386 
387 #ifdef CONFIG_PM_SLEEP
388 static int pxa_rtc_suspend(struct device *dev)
389 {
390 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
391 
392 	if (device_may_wakeup(dev))
393 		enable_irq_wake(pxa_rtc->sa1100_rtc.irq_alarm);
394 	return 0;
395 }
396 
397 static int pxa_rtc_resume(struct device *dev)
398 {
399 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
400 
401 	if (device_may_wakeup(dev))
402 		disable_irq_wake(pxa_rtc->sa1100_rtc.irq_alarm);
403 	return 0;
404 }
405 #endif
406 
407 static SIMPLE_DEV_PM_OPS(pxa_rtc_pm_ops, pxa_rtc_suspend, pxa_rtc_resume);
408 
409 static struct platform_driver pxa_rtc_driver = {
410 	.remove		= __exit_p(pxa_rtc_remove),
411 	.driver		= {
412 		.name	= "pxa-rtc",
413 		.of_match_table = of_match_ptr(pxa_rtc_dt_ids),
414 		.pm	= &pxa_rtc_pm_ops,
415 	},
416 };
417 
418 module_platform_driver_probe(pxa_rtc_driver, pxa_rtc_probe);
419 
420 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
421 MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)");
422 MODULE_LICENSE("GPL");
423 MODULE_ALIAS("platform:pxa-rtc");
424