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
ryxr_calc(struct rtc_time * tm)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
rdxr_calc(struct rtc_time * tm)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
tm_calc(u32 rycr,u32 rdcr,struct rtc_time * tm)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
rtsr_clear_bits(struct pxa_rtc * pxa_rtc,u32 mask)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
rtsr_set_bits(struct pxa_rtc * pxa_rtc,u32 mask)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
pxa_rtc_irq(int irq,void * dev_id)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
pxa_rtc_open(struct device * dev)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
pxa_rtc_release(struct device * dev)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
pxa_alarm_irq_enable(struct device * dev,unsigned int enabled)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
pxa_rtc_read_time(struct device * dev,struct rtc_time * tm)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
pxa_rtc_set_time(struct device * dev,struct rtc_time * tm)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
pxa_rtc_read_alarm(struct device * dev,struct rtc_wkalrm * alrm)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
pxa_rtc_set_alarm(struct device * dev,struct rtc_wkalrm * alrm)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
pxa_rtc_proc(struct device * dev,struct seq_file * seq)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
pxa_rtc_probe(struct platform_device * pdev)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 pxa_rtc->base = devm_ioremap(dev, pxa_rtc->ress->start,
334 resource_size(pxa_rtc->ress));
335 if (!pxa_rtc->base) {
336 dev_err(dev, "Unable to map pxa RTC I/O memory\n");
337 return -ENOMEM;
338 }
339
340 pxa_rtc_open(dev);
341
342 sa1100_rtc->rcnr = pxa_rtc->base + 0x0;
343 sa1100_rtc->rtsr = pxa_rtc->base + 0x8;
344 sa1100_rtc->rtar = pxa_rtc->base + 0x4;
345 sa1100_rtc->rttr = pxa_rtc->base + 0xc;
346 ret = sa1100_rtc_init(pdev, sa1100_rtc);
347 if (ret) {
348 dev_err(dev, "Unable to init SA1100 RTC sub-device\n");
349 return ret;
350 }
351
352 rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
353
354 pxa_rtc->rtc = devm_rtc_device_register(&pdev->dev, "pxa-rtc",
355 &pxa_rtc_ops, THIS_MODULE);
356 if (IS_ERR(pxa_rtc->rtc)) {
357 ret = PTR_ERR(pxa_rtc->rtc);
358 dev_err(dev, "Failed to register RTC device -> %d\n", ret);
359 return ret;
360 }
361
362 device_init_wakeup(dev, 1);
363
364 return 0;
365 }
366
pxa_rtc_remove(struct platform_device * pdev)367 static int __exit pxa_rtc_remove(struct platform_device *pdev)
368 {
369 struct device *dev = &pdev->dev;
370
371 pxa_rtc_release(dev);
372 return 0;
373 }
374
375 #ifdef CONFIG_OF
376 static const struct of_device_id pxa_rtc_dt_ids[] = {
377 { .compatible = "marvell,pxa-rtc" },
378 {}
379 };
380 MODULE_DEVICE_TABLE(of, pxa_rtc_dt_ids);
381 #endif
382
383 #ifdef CONFIG_PM_SLEEP
pxa_rtc_suspend(struct device * dev)384 static int pxa_rtc_suspend(struct device *dev)
385 {
386 struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
387
388 if (device_may_wakeup(dev))
389 enable_irq_wake(pxa_rtc->sa1100_rtc.irq_alarm);
390 return 0;
391 }
392
pxa_rtc_resume(struct device * dev)393 static int pxa_rtc_resume(struct device *dev)
394 {
395 struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
396
397 if (device_may_wakeup(dev))
398 disable_irq_wake(pxa_rtc->sa1100_rtc.irq_alarm);
399 return 0;
400 }
401 #endif
402
403 static SIMPLE_DEV_PM_OPS(pxa_rtc_pm_ops, pxa_rtc_suspend, pxa_rtc_resume);
404
405 static struct platform_driver pxa_rtc_driver = {
406 .remove = __exit_p(pxa_rtc_remove),
407 .driver = {
408 .name = "pxa-rtc",
409 .of_match_table = of_match_ptr(pxa_rtc_dt_ids),
410 .pm = &pxa_rtc_pm_ops,
411 },
412 };
413
414 module_platform_driver_probe(pxa_rtc_driver, pxa_rtc_probe);
415
416 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
417 MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)");
418 MODULE_LICENSE("GPL");
419 MODULE_ALIAS("platform:pxa-rtc");
420