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