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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * An RTC driver for Allwinner A10/A20
4 *
5 * Copyright (c) 2013, Carlo Caione <carlo.caione@gmail.com>
6 */
7
8#include <linux/delay.h>
9#include <linux/err.h>
10#include <linux/fs.h>
11#include <linux/init.h>
12#include <linux/interrupt.h>
13#include <linux/io.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/of_address.h>
18#include <linux/of_device.h>
19#include <linux/platform_device.h>
20#include <linux/rtc.h>
21#include <linux/types.h>
22
23#define SUNXI_LOSC_CTRL 0x0000
24#define SUNXI_LOSC_CTRL_RTC_HMS_ACC BIT(8)
25#define SUNXI_LOSC_CTRL_RTC_YMD_ACC BIT(7)
26
27#define SUNXI_RTC_YMD 0x0004
28
29#define SUNXI_RTC_HMS 0x0008
30
31#define SUNXI_ALRM_DHMS 0x000c
32
33#define SUNXI_ALRM_EN 0x0014
34#define SUNXI_ALRM_EN_CNT_EN BIT(8)
35
36#define SUNXI_ALRM_IRQ_EN 0x0018
37#define SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN BIT(0)
38
39#define SUNXI_ALRM_IRQ_STA 0x001c
40#define SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND BIT(0)
41
42#define SUNXI_MASK_DH 0x0000001f
43#define SUNXI_MASK_SM 0x0000003f
44#define SUNXI_MASK_M 0x0000000f
45#define SUNXI_MASK_LY 0x00000001
46#define SUNXI_MASK_D 0x00000ffe
47#define SUNXI_MASK_M 0x0000000f
48
49#define SUNXI_GET(x, mask, shift) (((x) & ((mask) << (shift))) \
50 >> (shift))
51
52#define SUNXI_SET(x, mask, shift) (((x) & (mask)) << (shift))
53
54/*
55 * Get date values
56 */
57#define SUNXI_DATE_GET_DAY_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 0)
58#define SUNXI_DATE_GET_MON_VALUE(x) SUNXI_GET(x, SUNXI_MASK_M, 8)
59#define SUNXI_DATE_GET_YEAR_VALUE(x, mask) SUNXI_GET(x, mask, 16)
60
61/*
62 * Get time values
63 */
64#define SUNXI_TIME_GET_SEC_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 0)
65#define SUNXI_TIME_GET_MIN_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 8)
66#define SUNXI_TIME_GET_HOUR_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 16)
67
68/*
69 * Get alarm values
70 */
71#define SUNXI_ALRM_GET_SEC_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 0)
72#define SUNXI_ALRM_GET_MIN_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 8)
73#define SUNXI_ALRM_GET_HOUR_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 16)
74
75/*
76 * Set date values
77 */
78#define SUNXI_DATE_SET_DAY_VALUE(x) SUNXI_DATE_GET_DAY_VALUE(x)
79#define SUNXI_DATE_SET_MON_VALUE(x) SUNXI_SET(x, SUNXI_MASK_M, 8)
80#define SUNXI_DATE_SET_YEAR_VALUE(x, mask) SUNXI_SET(x, mask, 16)
81#define SUNXI_LEAP_SET_VALUE(x, shift) SUNXI_SET(x, SUNXI_MASK_LY, shift)
82
83/*
84 * Set time values
85 */
86#define SUNXI_TIME_SET_SEC_VALUE(x) SUNXI_TIME_GET_SEC_VALUE(x)
87#define SUNXI_TIME_SET_MIN_VALUE(x) SUNXI_SET(x, SUNXI_MASK_SM, 8)
88#define SUNXI_TIME_SET_HOUR_VALUE(x) SUNXI_SET(x, SUNXI_MASK_DH, 16)
89
90/*
91 * Set alarm values
92 */
93#define SUNXI_ALRM_SET_SEC_VALUE(x) SUNXI_ALRM_GET_SEC_VALUE(x)
94#define SUNXI_ALRM_SET_MIN_VALUE(x) SUNXI_SET(x, SUNXI_MASK_SM, 8)
95#define SUNXI_ALRM_SET_HOUR_VALUE(x) SUNXI_SET(x, SUNXI_MASK_DH, 16)
96#define SUNXI_ALRM_SET_DAY_VALUE(x) SUNXI_SET(x, SUNXI_MASK_D, 21)
97
98/*
99 * Time unit conversions
100 */
101#define SEC_IN_MIN 60
102#define SEC_IN_HOUR (60 * SEC_IN_MIN)
103#define SEC_IN_DAY (24 * SEC_IN_HOUR)
104
105/*
106 * The year parameter passed to the driver is usually an offset relative to
107 * the year 1900. This macro is used to convert this offset to another one
108 * relative to the minimum year allowed by the hardware.
109 */
110#define SUNXI_YEAR_OFF(x) ((x)->min - 1900)
111
112/*
113 * min and max year are arbitrary set considering the limited range of the
114 * hardware register field
115 */
116struct sunxi_rtc_data_year {
117 unsigned int min; /* min year allowed */
118 unsigned int max; /* max year allowed */
119 unsigned int mask; /* mask for the year field */
120 unsigned char leap_shift; /* bit shift to get the leap year */
121};
122
123static const struct sunxi_rtc_data_year data_year_param[] = {
124 [0] = {
125 .min = 2010,
126 .max = 2073,
127 .mask = 0x3f,
128 .leap_shift = 22,
129 },
130 [1] = {
131 .min = 1970,
132 .max = 2225,
133 .mask = 0xff,
134 .leap_shift = 24,
135 },
136};
137
138struct sunxi_rtc_dev {
139 struct rtc_device *rtc;
140 struct device *dev;
141 const struct sunxi_rtc_data_year *data_year;
142 void __iomem *base;
143 int irq;
144};
145
146static irqreturn_t sunxi_rtc_alarmirq(int irq, void *id)
147{
148 struct sunxi_rtc_dev *chip = (struct sunxi_rtc_dev *) id;
149 u32 val;
150
151 val = readl(chip->base + SUNXI_ALRM_IRQ_STA);
152
153 if (val & SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND) {
154 val |= SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND;
155 writel(val, chip->base + SUNXI_ALRM_IRQ_STA);
156
157 rtc_update_irq(chip->rtc, 1, RTC_AF | RTC_IRQF);
158
159 return IRQ_HANDLED;
160 }
161
162 return IRQ_NONE;
163}
164
165static void sunxi_rtc_setaie(unsigned int to, struct sunxi_rtc_dev *chip)
166{
167 u32 alrm_val = 0;
168 u32 alrm_irq_val = 0;
169
170 if (to) {
171 alrm_val = readl(chip->base + SUNXI_ALRM_EN);
172 alrm_val |= SUNXI_ALRM_EN_CNT_EN;
173
174 alrm_irq_val = readl(chip->base + SUNXI_ALRM_IRQ_EN);
175 alrm_irq_val |= SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN;
176 } else {
177 writel(SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND,
178 chip->base + SUNXI_ALRM_IRQ_STA);
179 }
180
181 writel(alrm_val, chip->base + SUNXI_ALRM_EN);
182 writel(alrm_irq_val, chip->base + SUNXI_ALRM_IRQ_EN);
183}
184
185static int sunxi_rtc_getalarm(struct device *dev, struct rtc_wkalrm *wkalrm)
186{
187 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
188 struct rtc_time *alrm_tm = &wkalrm->time;
189 u32 alrm;
190 u32 alrm_en;
191 u32 date;
192
193 alrm = readl(chip->base + SUNXI_ALRM_DHMS);
194 date = readl(chip->base + SUNXI_RTC_YMD);
195
196 alrm_tm->tm_sec = SUNXI_ALRM_GET_SEC_VALUE(alrm);
197 alrm_tm->tm_min = SUNXI_ALRM_GET_MIN_VALUE(alrm);
198 alrm_tm->tm_hour = SUNXI_ALRM_GET_HOUR_VALUE(alrm);
199
200 alrm_tm->tm_mday = SUNXI_DATE_GET_DAY_VALUE(date);
201 alrm_tm->tm_mon = SUNXI_DATE_GET_MON_VALUE(date);
202 alrm_tm->tm_year = SUNXI_DATE_GET_YEAR_VALUE(date,
203 chip->data_year->mask);
204
205 alrm_tm->tm_mon -= 1;
206
207 /*
208 * switch from (data_year->min)-relative offset to
209 * a (1900)-relative one
210 */
211 alrm_tm->tm_year += SUNXI_YEAR_OFF(chip->data_year);
212
213 alrm_en = readl(chip->base + SUNXI_ALRM_IRQ_EN);
214 if (alrm_en & SUNXI_ALRM_EN_CNT_EN)
215 wkalrm->enabled = 1;
216
217 return 0;
218}
219
220static int sunxi_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
221{
222 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
223 u32 date, time;
224
225 /*
226 * read again in case it changes
227 */
228 do {
229 date = readl(chip->base + SUNXI_RTC_YMD);
230 time = readl(chip->base + SUNXI_RTC_HMS);
231 } while ((date != readl(chip->base + SUNXI_RTC_YMD)) ||
232 (time != readl(chip->base + SUNXI_RTC_HMS)));
233
234 rtc_tm->tm_sec = SUNXI_TIME_GET_SEC_VALUE(time);
235 rtc_tm->tm_min = SUNXI_TIME_GET_MIN_VALUE(time);
236 rtc_tm->tm_hour = SUNXI_TIME_GET_HOUR_VALUE(time);
237
238 rtc_tm->tm_mday = SUNXI_DATE_GET_DAY_VALUE(date);
239 rtc_tm->tm_mon = SUNXI_DATE_GET_MON_VALUE(date);
240 rtc_tm->tm_year = SUNXI_DATE_GET_YEAR_VALUE(date,
241 chip->data_year->mask);
242
243 rtc_tm->tm_mon -= 1;
244
245 /*
246 * switch from (data_year->min)-relative offset to
247 * a (1900)-relative one
248 */
249 rtc_tm->tm_year += SUNXI_YEAR_OFF(chip->data_year);
250
251 return 0;
252}
253
254static int sunxi_rtc_setalarm(struct device *dev, struct rtc_wkalrm *wkalrm)
255{
256 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
257 struct rtc_time *alrm_tm = &wkalrm->time;
258 struct rtc_time tm_now;
259 u32 alrm;
260 time64_t diff;
261 unsigned long time_gap;
262 unsigned long time_gap_day;
263 unsigned long time_gap_hour;
264 unsigned long time_gap_min;
265 int ret;
266
267 ret = sunxi_rtc_gettime(dev, &tm_now);
268 if (ret < 0) {
269 dev_err(dev, "Error in getting time\n");
270 return -EINVAL;
271 }
272
273 diff = rtc_tm_sub(alrm_tm, &tm_now);
274 if (diff <= 0) {
275 dev_err(dev, "Date to set in the past\n");
276 return -EINVAL;
277 }
278
279 if (diff > 255 * SEC_IN_DAY) {
280 dev_err(dev, "Day must be in the range 0 - 255\n");
281 return -EINVAL;
282 }
283
284 time_gap = diff;
285 time_gap_day = time_gap / SEC_IN_DAY;
286 time_gap -= time_gap_day * SEC_IN_DAY;
287 time_gap_hour = time_gap / SEC_IN_HOUR;
288 time_gap -= time_gap_hour * SEC_IN_HOUR;
289 time_gap_min = time_gap / SEC_IN_MIN;
290 time_gap -= time_gap_min * SEC_IN_MIN;
291
292 sunxi_rtc_setaie(0, chip);
293 writel(0, chip->base + SUNXI_ALRM_DHMS);
294 usleep_range(100, 300);
295
296 alrm = SUNXI_ALRM_SET_SEC_VALUE(time_gap) |
297 SUNXI_ALRM_SET_MIN_VALUE(time_gap_min) |
298 SUNXI_ALRM_SET_HOUR_VALUE(time_gap_hour) |
299 SUNXI_ALRM_SET_DAY_VALUE(time_gap_day);
300 writel(alrm, chip->base + SUNXI_ALRM_DHMS);
301
302 writel(0, chip->base + SUNXI_ALRM_IRQ_EN);
303 writel(SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN, chip->base + SUNXI_ALRM_IRQ_EN);
304
305 sunxi_rtc_setaie(wkalrm->enabled, chip);
306
307 return 0;
308}
309
310static int sunxi_rtc_wait(struct sunxi_rtc_dev *chip, int offset,
311 unsigned int mask, unsigned int ms_timeout)
312{
313 const unsigned long timeout = jiffies + msecs_to_jiffies(ms_timeout);
314 u32 reg;
315
316 do {
317 reg = readl(chip->base + offset);
318 reg &= mask;
319
320 if (reg == mask)
321 return 0;
322
323 } while (time_before(jiffies, timeout));
324
325 return -ETIMEDOUT;
326}
327
328static int sunxi_rtc_settime(struct device *dev, struct rtc_time *rtc_tm)
329{
330 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
331 u32 date = 0;
332 u32 time = 0;
333 unsigned int year;
334
335 /*
336 * the input rtc_tm->tm_year is the offset relative to 1900. We use
337 * the SUNXI_YEAR_OFF macro to rebase it with respect to the min year
338 * allowed by the hardware
339 */
340
341 year = rtc_tm->tm_year + 1900;
342 if (year < chip->data_year->min || year > chip->data_year->max) {
343 dev_err(dev, "rtc only supports year in range %u - %u\n",
344 chip->data_year->min, chip->data_year->max);
345 return -EINVAL;
346 }
347
348 rtc_tm->tm_year -= SUNXI_YEAR_OFF(chip->data_year);
349 rtc_tm->tm_mon += 1;
350
351 date = SUNXI_DATE_SET_DAY_VALUE(rtc_tm->tm_mday) |
352 SUNXI_DATE_SET_MON_VALUE(rtc_tm->tm_mon) |
353 SUNXI_DATE_SET_YEAR_VALUE(rtc_tm->tm_year,
354 chip->data_year->mask);
355
356 if (is_leap_year(year))
357 date |= SUNXI_LEAP_SET_VALUE(1, chip->data_year->leap_shift);
358
359 time = SUNXI_TIME_SET_SEC_VALUE(rtc_tm->tm_sec) |
360 SUNXI_TIME_SET_MIN_VALUE(rtc_tm->tm_min) |
361 SUNXI_TIME_SET_HOUR_VALUE(rtc_tm->tm_hour);
362
363 writel(0, chip->base + SUNXI_RTC_HMS);
364 writel(0, chip->base + SUNXI_RTC_YMD);
365
366 writel(time, chip->base + SUNXI_RTC_HMS);
367
368 /*
369 * After writing the RTC HH-MM-SS register, the
370 * SUNXI_LOSC_CTRL_RTC_HMS_ACC bit is set and it will not
371 * be cleared until the real writing operation is finished
372 */
373
374 if (sunxi_rtc_wait(chip, SUNXI_LOSC_CTRL,
375 SUNXI_LOSC_CTRL_RTC_HMS_ACC, 50)) {
376 dev_err(dev, "Failed to set rtc time.\n");
377 return -1;
378 }
379
380 writel(date, chip->base + SUNXI_RTC_YMD);
381
382 /*
383 * After writing the RTC YY-MM-DD register, the
384 * SUNXI_LOSC_CTRL_RTC_YMD_ACC bit is set and it will not
385 * be cleared until the real writing operation is finished
386 */
387
388 if (sunxi_rtc_wait(chip, SUNXI_LOSC_CTRL,
389 SUNXI_LOSC_CTRL_RTC_YMD_ACC, 50)) {
390 dev_err(dev, "Failed to set rtc time.\n");
391 return -1;
392 }
393
394 return 0;
395}
396
397static int sunxi_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
398{
399 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
400
401 if (!enabled)
402 sunxi_rtc_setaie(enabled, chip);
403
404 return 0;
405}
406
407static const struct rtc_class_ops sunxi_rtc_ops = {
408 .read_time = sunxi_rtc_gettime,
409 .set_time = sunxi_rtc_settime,
410 .read_alarm = sunxi_rtc_getalarm,
411 .set_alarm = sunxi_rtc_setalarm,
412 .alarm_irq_enable = sunxi_rtc_alarm_irq_enable
413};
414
415static const struct of_device_id sunxi_rtc_dt_ids[] = {
416 { .compatible = "allwinner,sun4i-a10-rtc", .data = &data_year_param[0] },
417 { .compatible = "allwinner,sun7i-a20-rtc", .data = &data_year_param[1] },
418 { /* sentinel */ },
419};
420MODULE_DEVICE_TABLE(of, sunxi_rtc_dt_ids);
421
422static int sunxi_rtc_probe(struct platform_device *pdev)
423{
424 struct sunxi_rtc_dev *chip;
425 int ret;
426
427 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
428 if (!chip)
429 return -ENOMEM;
430
431 platform_set_drvdata(pdev, chip);
432 chip->dev = &pdev->dev;
433
434 chip->rtc = devm_rtc_allocate_device(&pdev->dev);
435 if (IS_ERR(chip->rtc))
436 return PTR_ERR(chip->rtc);
437
438 chip->base = devm_platform_ioremap_resource(pdev, 0);
439 if (IS_ERR(chip->base))
440 return PTR_ERR(chip->base);
441
442 chip->irq = platform_get_irq(pdev, 0);
443 if (chip->irq < 0)
444 return chip->irq;
445 ret = devm_request_irq(&pdev->dev, chip->irq, sunxi_rtc_alarmirq,
446 0, dev_name(&pdev->dev), chip);
447 if (ret) {
448 dev_err(&pdev->dev, "Could not request IRQ\n");
449 return ret;
450 }
451
452 chip->data_year = of_device_get_match_data(&pdev->dev);
453 if (!chip->data_year) {
454 dev_err(&pdev->dev, "Unable to setup RTC data\n");
455 return -ENODEV;
456 }
457
458 /* clear the alarm count value */
459 writel(0, chip->base + SUNXI_ALRM_DHMS);
460
461 /* disable alarm, not generate irq pending */
462 writel(0, chip->base + SUNXI_ALRM_EN);
463
464 /* disable alarm week/cnt irq, unset to cpu */
465 writel(0, chip->base + SUNXI_ALRM_IRQ_EN);
466
467 /* clear alarm week/cnt irq pending */
468 writel(SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND, chip->base +
469 SUNXI_ALRM_IRQ_STA);
470
471 chip->rtc->ops = &sunxi_rtc_ops;
472
473 return rtc_register_device(chip->rtc);
474}
475
476static struct platform_driver sunxi_rtc_driver = {
477 .probe = sunxi_rtc_probe,
478 .driver = {
479 .name = "sunxi-rtc",
480 .of_match_table = sunxi_rtc_dt_ids,
481 },
482};
483
484module_platform_driver(sunxi_rtc_driver);
485
486MODULE_DESCRIPTION("sunxi RTC driver");
487MODULE_AUTHOR("Carlo Caione <carlo.caione@gmail.com>");
488MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * An RTC driver for Allwinner A10/A20
4 *
5 * Copyright (c) 2013, Carlo Caione <carlo.caione@gmail.com>
6 */
7
8#include <linux/delay.h>
9#include <linux/err.h>
10#include <linux/fs.h>
11#include <linux/init.h>
12#include <linux/interrupt.h>
13#include <linux/io.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/of_address.h>
18#include <linux/of_device.h>
19#include <linux/platform_device.h>
20#include <linux/rtc.h>
21#include <linux/types.h>
22
23#define SUNXI_LOSC_CTRL 0x0000
24#define SUNXI_LOSC_CTRL_RTC_HMS_ACC BIT(8)
25#define SUNXI_LOSC_CTRL_RTC_YMD_ACC BIT(7)
26
27#define SUNXI_RTC_YMD 0x0004
28
29#define SUNXI_RTC_HMS 0x0008
30
31#define SUNXI_ALRM_DHMS 0x000c
32
33#define SUNXI_ALRM_EN 0x0014
34#define SUNXI_ALRM_EN_CNT_EN BIT(8)
35
36#define SUNXI_ALRM_IRQ_EN 0x0018
37#define SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN BIT(0)
38
39#define SUNXI_ALRM_IRQ_STA 0x001c
40#define SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND BIT(0)
41
42#define SUNXI_MASK_DH 0x0000001f
43#define SUNXI_MASK_SM 0x0000003f
44#define SUNXI_MASK_M 0x0000000f
45#define SUNXI_MASK_LY 0x00000001
46#define SUNXI_MASK_D 0x00000ffe
47#define SUNXI_MASK_M 0x0000000f
48
49#define SUNXI_GET(x, mask, shift) (((x) & ((mask) << (shift))) \
50 >> (shift))
51
52#define SUNXI_SET(x, mask, shift) (((x) & (mask)) << (shift))
53
54/*
55 * Get date values
56 */
57#define SUNXI_DATE_GET_DAY_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 0)
58#define SUNXI_DATE_GET_MON_VALUE(x) SUNXI_GET(x, SUNXI_MASK_M, 8)
59#define SUNXI_DATE_GET_YEAR_VALUE(x, mask) SUNXI_GET(x, mask, 16)
60
61/*
62 * Get time values
63 */
64#define SUNXI_TIME_GET_SEC_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 0)
65#define SUNXI_TIME_GET_MIN_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 8)
66#define SUNXI_TIME_GET_HOUR_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 16)
67
68/*
69 * Get alarm values
70 */
71#define SUNXI_ALRM_GET_SEC_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 0)
72#define SUNXI_ALRM_GET_MIN_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 8)
73#define SUNXI_ALRM_GET_HOUR_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 16)
74
75/*
76 * Set date values
77 */
78#define SUNXI_DATE_SET_DAY_VALUE(x) SUNXI_DATE_GET_DAY_VALUE(x)
79#define SUNXI_DATE_SET_MON_VALUE(x) SUNXI_SET(x, SUNXI_MASK_M, 8)
80#define SUNXI_DATE_SET_YEAR_VALUE(x, mask) SUNXI_SET(x, mask, 16)
81#define SUNXI_LEAP_SET_VALUE(x, shift) SUNXI_SET(x, SUNXI_MASK_LY, shift)
82
83/*
84 * Set time values
85 */
86#define SUNXI_TIME_SET_SEC_VALUE(x) SUNXI_TIME_GET_SEC_VALUE(x)
87#define SUNXI_TIME_SET_MIN_VALUE(x) SUNXI_SET(x, SUNXI_MASK_SM, 8)
88#define SUNXI_TIME_SET_HOUR_VALUE(x) SUNXI_SET(x, SUNXI_MASK_DH, 16)
89
90/*
91 * Set alarm values
92 */
93#define SUNXI_ALRM_SET_SEC_VALUE(x) SUNXI_ALRM_GET_SEC_VALUE(x)
94#define SUNXI_ALRM_SET_MIN_VALUE(x) SUNXI_SET(x, SUNXI_MASK_SM, 8)
95#define SUNXI_ALRM_SET_HOUR_VALUE(x) SUNXI_SET(x, SUNXI_MASK_DH, 16)
96#define SUNXI_ALRM_SET_DAY_VALUE(x) SUNXI_SET(x, SUNXI_MASK_D, 21)
97
98/*
99 * Time unit conversions
100 */
101#define SEC_IN_MIN 60
102#define SEC_IN_HOUR (60 * SEC_IN_MIN)
103#define SEC_IN_DAY (24 * SEC_IN_HOUR)
104
105/*
106 * The year parameter passed to the driver is usually an offset relative to
107 * the year 1900. This macro is used to convert this offset to another one
108 * relative to the minimum year allowed by the hardware.
109 */
110#define SUNXI_YEAR_OFF(x) ((x)->min - 1900)
111
112/*
113 * min and max year are arbitrary set considering the limited range of the
114 * hardware register field
115 */
116struct sunxi_rtc_data_year {
117 unsigned int min; /* min year allowed */
118 unsigned int max; /* max year allowed */
119 unsigned int mask; /* mask for the year field */
120 unsigned char leap_shift; /* bit shift to get the leap year */
121};
122
123static const struct sunxi_rtc_data_year data_year_param[] = {
124 [0] = {
125 .min = 2010,
126 .max = 2073,
127 .mask = 0x3f,
128 .leap_shift = 22,
129 },
130 [1] = {
131 .min = 1970,
132 .max = 2225,
133 .mask = 0xff,
134 .leap_shift = 24,
135 },
136};
137
138struct sunxi_rtc_dev {
139 struct rtc_device *rtc;
140 struct device *dev;
141 const struct sunxi_rtc_data_year *data_year;
142 void __iomem *base;
143 int irq;
144};
145
146static irqreturn_t sunxi_rtc_alarmirq(int irq, void *id)
147{
148 struct sunxi_rtc_dev *chip = (struct sunxi_rtc_dev *) id;
149 u32 val;
150
151 val = readl(chip->base + SUNXI_ALRM_IRQ_STA);
152
153 if (val & SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND) {
154 val |= SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND;
155 writel(val, chip->base + SUNXI_ALRM_IRQ_STA);
156
157 rtc_update_irq(chip->rtc, 1, RTC_AF | RTC_IRQF);
158
159 return IRQ_HANDLED;
160 }
161
162 return IRQ_NONE;
163}
164
165static void sunxi_rtc_setaie(unsigned int to, struct sunxi_rtc_dev *chip)
166{
167 u32 alrm_val = 0;
168 u32 alrm_irq_val = 0;
169
170 if (to) {
171 alrm_val = readl(chip->base + SUNXI_ALRM_EN);
172 alrm_val |= SUNXI_ALRM_EN_CNT_EN;
173
174 alrm_irq_val = readl(chip->base + SUNXI_ALRM_IRQ_EN);
175 alrm_irq_val |= SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN;
176 } else {
177 writel(SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND,
178 chip->base + SUNXI_ALRM_IRQ_STA);
179 }
180
181 writel(alrm_val, chip->base + SUNXI_ALRM_EN);
182 writel(alrm_irq_val, chip->base + SUNXI_ALRM_IRQ_EN);
183}
184
185static int sunxi_rtc_getalarm(struct device *dev, struct rtc_wkalrm *wkalrm)
186{
187 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
188 struct rtc_time *alrm_tm = &wkalrm->time;
189 u32 alrm;
190 u32 alrm_en;
191 u32 date;
192
193 alrm = readl(chip->base + SUNXI_ALRM_DHMS);
194 date = readl(chip->base + SUNXI_RTC_YMD);
195
196 alrm_tm->tm_sec = SUNXI_ALRM_GET_SEC_VALUE(alrm);
197 alrm_tm->tm_min = SUNXI_ALRM_GET_MIN_VALUE(alrm);
198 alrm_tm->tm_hour = SUNXI_ALRM_GET_HOUR_VALUE(alrm);
199
200 alrm_tm->tm_mday = SUNXI_DATE_GET_DAY_VALUE(date);
201 alrm_tm->tm_mon = SUNXI_DATE_GET_MON_VALUE(date);
202 alrm_tm->tm_year = SUNXI_DATE_GET_YEAR_VALUE(date,
203 chip->data_year->mask);
204
205 alrm_tm->tm_mon -= 1;
206
207 /*
208 * switch from (data_year->min)-relative offset to
209 * a (1900)-relative one
210 */
211 alrm_tm->tm_year += SUNXI_YEAR_OFF(chip->data_year);
212
213 alrm_en = readl(chip->base + SUNXI_ALRM_IRQ_EN);
214 if (alrm_en & SUNXI_ALRM_EN_CNT_EN)
215 wkalrm->enabled = 1;
216
217 return 0;
218}
219
220static int sunxi_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
221{
222 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
223 u32 date, time;
224
225 /*
226 * read again in case it changes
227 */
228 do {
229 date = readl(chip->base + SUNXI_RTC_YMD);
230 time = readl(chip->base + SUNXI_RTC_HMS);
231 } while ((date != readl(chip->base + SUNXI_RTC_YMD)) ||
232 (time != readl(chip->base + SUNXI_RTC_HMS)));
233
234 rtc_tm->tm_sec = SUNXI_TIME_GET_SEC_VALUE(time);
235 rtc_tm->tm_min = SUNXI_TIME_GET_MIN_VALUE(time);
236 rtc_tm->tm_hour = SUNXI_TIME_GET_HOUR_VALUE(time);
237
238 rtc_tm->tm_mday = SUNXI_DATE_GET_DAY_VALUE(date);
239 rtc_tm->tm_mon = SUNXI_DATE_GET_MON_VALUE(date);
240 rtc_tm->tm_year = SUNXI_DATE_GET_YEAR_VALUE(date,
241 chip->data_year->mask);
242
243 rtc_tm->tm_mon -= 1;
244
245 /*
246 * switch from (data_year->min)-relative offset to
247 * a (1900)-relative one
248 */
249 rtc_tm->tm_year += SUNXI_YEAR_OFF(chip->data_year);
250
251 return 0;
252}
253
254static int sunxi_rtc_setalarm(struct device *dev, struct rtc_wkalrm *wkalrm)
255{
256 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
257 struct rtc_time *alrm_tm = &wkalrm->time;
258 struct rtc_time tm_now;
259 u32 alrm;
260 time64_t diff;
261 unsigned long time_gap;
262 unsigned long time_gap_day;
263 unsigned long time_gap_hour;
264 unsigned long time_gap_min;
265 int ret;
266
267 ret = sunxi_rtc_gettime(dev, &tm_now);
268 if (ret < 0) {
269 dev_err(dev, "Error in getting time\n");
270 return -EINVAL;
271 }
272
273 diff = rtc_tm_sub(alrm_tm, &tm_now);
274 if (diff <= 0) {
275 dev_err(dev, "Date to set in the past\n");
276 return -EINVAL;
277 }
278
279 if (diff > 255 * SEC_IN_DAY) {
280 dev_err(dev, "Day must be in the range 0 - 255\n");
281 return -EINVAL;
282 }
283
284 time_gap = diff;
285 time_gap_day = time_gap / SEC_IN_DAY;
286 time_gap -= time_gap_day * SEC_IN_DAY;
287 time_gap_hour = time_gap / SEC_IN_HOUR;
288 time_gap -= time_gap_hour * SEC_IN_HOUR;
289 time_gap_min = time_gap / SEC_IN_MIN;
290 time_gap -= time_gap_min * SEC_IN_MIN;
291
292 sunxi_rtc_setaie(0, chip);
293 writel(0, chip->base + SUNXI_ALRM_DHMS);
294 usleep_range(100, 300);
295
296 alrm = SUNXI_ALRM_SET_SEC_VALUE(time_gap) |
297 SUNXI_ALRM_SET_MIN_VALUE(time_gap_min) |
298 SUNXI_ALRM_SET_HOUR_VALUE(time_gap_hour) |
299 SUNXI_ALRM_SET_DAY_VALUE(time_gap_day);
300 writel(alrm, chip->base + SUNXI_ALRM_DHMS);
301
302 writel(0, chip->base + SUNXI_ALRM_IRQ_EN);
303 writel(SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN, chip->base + SUNXI_ALRM_IRQ_EN);
304
305 sunxi_rtc_setaie(wkalrm->enabled, chip);
306
307 return 0;
308}
309
310static int sunxi_rtc_wait(struct sunxi_rtc_dev *chip, int offset,
311 unsigned int mask, unsigned int ms_timeout)
312{
313 const unsigned long timeout = jiffies + msecs_to_jiffies(ms_timeout);
314 u32 reg;
315
316 do {
317 reg = readl(chip->base + offset);
318 reg &= mask;
319
320 if (reg == mask)
321 return 0;
322
323 } while (time_before(jiffies, timeout));
324
325 return -ETIMEDOUT;
326}
327
328static int sunxi_rtc_settime(struct device *dev, struct rtc_time *rtc_tm)
329{
330 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
331 u32 date = 0;
332 u32 time = 0;
333 unsigned int year;
334
335 /*
336 * the input rtc_tm->tm_year is the offset relative to 1900. We use
337 * the SUNXI_YEAR_OFF macro to rebase it with respect to the min year
338 * allowed by the hardware
339 */
340
341 year = rtc_tm->tm_year + 1900;
342 if (year < chip->data_year->min || year > chip->data_year->max) {
343 dev_err(dev, "rtc only supports year in range %u - %u\n",
344 chip->data_year->min, chip->data_year->max);
345 return -EINVAL;
346 }
347
348 rtc_tm->tm_year -= SUNXI_YEAR_OFF(chip->data_year);
349 rtc_tm->tm_mon += 1;
350
351 date = SUNXI_DATE_SET_DAY_VALUE(rtc_tm->tm_mday) |
352 SUNXI_DATE_SET_MON_VALUE(rtc_tm->tm_mon) |
353 SUNXI_DATE_SET_YEAR_VALUE(rtc_tm->tm_year,
354 chip->data_year->mask);
355
356 if (is_leap_year(year))
357 date |= SUNXI_LEAP_SET_VALUE(1, chip->data_year->leap_shift);
358
359 time = SUNXI_TIME_SET_SEC_VALUE(rtc_tm->tm_sec) |
360 SUNXI_TIME_SET_MIN_VALUE(rtc_tm->tm_min) |
361 SUNXI_TIME_SET_HOUR_VALUE(rtc_tm->tm_hour);
362
363 writel(0, chip->base + SUNXI_RTC_HMS);
364 writel(0, chip->base + SUNXI_RTC_YMD);
365
366 writel(time, chip->base + SUNXI_RTC_HMS);
367
368 /*
369 * After writing the RTC HH-MM-SS register, the
370 * SUNXI_LOSC_CTRL_RTC_HMS_ACC bit is set and it will not
371 * be cleared until the real writing operation is finished
372 */
373
374 if (sunxi_rtc_wait(chip, SUNXI_LOSC_CTRL,
375 SUNXI_LOSC_CTRL_RTC_HMS_ACC, 50)) {
376 dev_err(dev, "Failed to set rtc time.\n");
377 return -1;
378 }
379
380 writel(date, chip->base + SUNXI_RTC_YMD);
381
382 /*
383 * After writing the RTC YY-MM-DD register, the
384 * SUNXI_LOSC_CTRL_RTC_YMD_ACC bit is set and it will not
385 * be cleared until the real writing operation is finished
386 */
387
388 if (sunxi_rtc_wait(chip, SUNXI_LOSC_CTRL,
389 SUNXI_LOSC_CTRL_RTC_YMD_ACC, 50)) {
390 dev_err(dev, "Failed to set rtc time.\n");
391 return -1;
392 }
393
394 return 0;
395}
396
397static int sunxi_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
398{
399 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
400
401 if (!enabled)
402 sunxi_rtc_setaie(enabled, chip);
403
404 return 0;
405}
406
407static const struct rtc_class_ops sunxi_rtc_ops = {
408 .read_time = sunxi_rtc_gettime,
409 .set_time = sunxi_rtc_settime,
410 .read_alarm = sunxi_rtc_getalarm,
411 .set_alarm = sunxi_rtc_setalarm,
412 .alarm_irq_enable = sunxi_rtc_alarm_irq_enable
413};
414
415static const struct of_device_id sunxi_rtc_dt_ids[] = {
416 { .compatible = "allwinner,sun4i-a10-rtc", .data = &data_year_param[0] },
417 { .compatible = "allwinner,sun7i-a20-rtc", .data = &data_year_param[1] },
418 { /* sentinel */ },
419};
420MODULE_DEVICE_TABLE(of, sunxi_rtc_dt_ids);
421
422static int sunxi_rtc_probe(struct platform_device *pdev)
423{
424 struct sunxi_rtc_dev *chip;
425 struct resource *res;
426 int ret;
427
428 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
429 if (!chip)
430 return -ENOMEM;
431
432 platform_set_drvdata(pdev, chip);
433 chip->dev = &pdev->dev;
434
435 chip->rtc = devm_rtc_allocate_device(&pdev->dev);
436 if (IS_ERR(chip->rtc))
437 return PTR_ERR(chip->rtc);
438
439 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
440 chip->base = devm_ioremap_resource(&pdev->dev, res);
441 if (IS_ERR(chip->base))
442 return PTR_ERR(chip->base);
443
444 chip->irq = platform_get_irq(pdev, 0);
445 if (chip->irq < 0)
446 return chip->irq;
447 ret = devm_request_irq(&pdev->dev, chip->irq, sunxi_rtc_alarmirq,
448 0, dev_name(&pdev->dev), chip);
449 if (ret) {
450 dev_err(&pdev->dev, "Could not request IRQ\n");
451 return ret;
452 }
453
454 chip->data_year = of_device_get_match_data(&pdev->dev);
455 if (!chip->data_year) {
456 dev_err(&pdev->dev, "Unable to setup RTC data\n");
457 return -ENODEV;
458 }
459
460 /* clear the alarm count value */
461 writel(0, chip->base + SUNXI_ALRM_DHMS);
462
463 /* disable alarm, not generate irq pending */
464 writel(0, chip->base + SUNXI_ALRM_EN);
465
466 /* disable alarm week/cnt irq, unset to cpu */
467 writel(0, chip->base + SUNXI_ALRM_IRQ_EN);
468
469 /* clear alarm week/cnt irq pending */
470 writel(SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND, chip->base +
471 SUNXI_ALRM_IRQ_STA);
472
473 chip->rtc->ops = &sunxi_rtc_ops;
474
475 return rtc_register_device(chip->rtc);
476}
477
478static struct platform_driver sunxi_rtc_driver = {
479 .probe = sunxi_rtc_probe,
480 .driver = {
481 .name = "sunxi-rtc",
482 .of_match_table = sunxi_rtc_dt_ids,
483 },
484};
485
486module_platform_driver(sunxi_rtc_driver);
487
488MODULE_DESCRIPTION("sunxi RTC driver");
489MODULE_AUTHOR("Carlo Caione <carlo.caione@gmail.com>");
490MODULE_LICENSE("GPL");