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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/platform_device.h>
18#include <linux/rtc.h>
19#include <linux/types.h>
20
21#define SUNXI_LOSC_CTRL 0x0000
22#define SUNXI_LOSC_CTRL_RTC_HMS_ACC BIT(8)
23#define SUNXI_LOSC_CTRL_RTC_YMD_ACC BIT(7)
24
25#define SUNXI_RTC_YMD 0x0004
26
27#define SUNXI_RTC_HMS 0x0008
28
29#define SUNXI_ALRM_DHMS 0x000c
30
31#define SUNXI_ALRM_EN 0x0014
32#define SUNXI_ALRM_EN_CNT_EN BIT(8)
33
34#define SUNXI_ALRM_IRQ_EN 0x0018
35#define SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN BIT(0)
36
37#define SUNXI_ALRM_IRQ_STA 0x001c
38#define SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND BIT(0)
39
40#define SUNXI_MASK_DH 0x0000001f
41#define SUNXI_MASK_SM 0x0000003f
42#define SUNXI_MASK_M 0x0000000f
43#define SUNXI_MASK_LY 0x00000001
44#define SUNXI_MASK_D 0x00000ffe
45#define SUNXI_MASK_M 0x0000000f
46
47#define SUNXI_GET(x, mask, shift) (((x) & ((mask) << (shift))) \
48 >> (shift))
49
50#define SUNXI_SET(x, mask, shift) (((x) & (mask)) << (shift))
51
52/*
53 * Get date values
54 */
55#define SUNXI_DATE_GET_DAY_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 0)
56#define SUNXI_DATE_GET_MON_VALUE(x) SUNXI_GET(x, SUNXI_MASK_M, 8)
57#define SUNXI_DATE_GET_YEAR_VALUE(x, mask) SUNXI_GET(x, mask, 16)
58
59/*
60 * Get time values
61 */
62#define SUNXI_TIME_GET_SEC_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 0)
63#define SUNXI_TIME_GET_MIN_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 8)
64#define SUNXI_TIME_GET_HOUR_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 16)
65
66/*
67 * Get alarm values
68 */
69#define SUNXI_ALRM_GET_SEC_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 0)
70#define SUNXI_ALRM_GET_MIN_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 8)
71#define SUNXI_ALRM_GET_HOUR_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 16)
72
73/*
74 * Set date values
75 */
76#define SUNXI_DATE_SET_DAY_VALUE(x) SUNXI_DATE_GET_DAY_VALUE(x)
77#define SUNXI_DATE_SET_MON_VALUE(x) SUNXI_SET(x, SUNXI_MASK_M, 8)
78#define SUNXI_DATE_SET_YEAR_VALUE(x, mask) SUNXI_SET(x, mask, 16)
79#define SUNXI_LEAP_SET_VALUE(x, shift) SUNXI_SET(x, SUNXI_MASK_LY, shift)
80
81/*
82 * Set time values
83 */
84#define SUNXI_TIME_SET_SEC_VALUE(x) SUNXI_TIME_GET_SEC_VALUE(x)
85#define SUNXI_TIME_SET_MIN_VALUE(x) SUNXI_SET(x, SUNXI_MASK_SM, 8)
86#define SUNXI_TIME_SET_HOUR_VALUE(x) SUNXI_SET(x, SUNXI_MASK_DH, 16)
87
88/*
89 * Set alarm values
90 */
91#define SUNXI_ALRM_SET_SEC_VALUE(x) SUNXI_ALRM_GET_SEC_VALUE(x)
92#define SUNXI_ALRM_SET_MIN_VALUE(x) SUNXI_SET(x, SUNXI_MASK_SM, 8)
93#define SUNXI_ALRM_SET_HOUR_VALUE(x) SUNXI_SET(x, SUNXI_MASK_DH, 16)
94#define SUNXI_ALRM_SET_DAY_VALUE(x) SUNXI_SET(x, SUNXI_MASK_D, 21)
95
96/*
97 * Time unit conversions
98 */
99#define SEC_IN_MIN 60
100#define SEC_IN_HOUR (60 * SEC_IN_MIN)
101#define SEC_IN_DAY (24 * SEC_IN_HOUR)
102
103/*
104 * The year parameter passed to the driver is usually an offset relative to
105 * the year 1900. This macro is used to convert this offset to another one
106 * relative to the minimum year allowed by the hardware.
107 */
108#define SUNXI_YEAR_OFF(x) ((x)->min - 1900)
109
110/*
111 * min and max year are arbitrary set considering the limited range of the
112 * hardware register field
113 */
114struct sunxi_rtc_data_year {
115 unsigned int min; /* min year allowed */
116 unsigned int max; /* max year allowed */
117 unsigned int mask; /* mask for the year field */
118 unsigned char leap_shift; /* bit shift to get the leap year */
119};
120
121static const struct sunxi_rtc_data_year data_year_param[] = {
122 [0] = {
123 .min = 2010,
124 .max = 2073,
125 .mask = 0x3f,
126 .leap_shift = 22,
127 },
128 [1] = {
129 .min = 1970,
130 .max = 2225,
131 .mask = 0xff,
132 .leap_shift = 24,
133 },
134};
135
136struct sunxi_rtc_dev {
137 struct rtc_device *rtc;
138 struct device *dev;
139 const struct sunxi_rtc_data_year *data_year;
140 void __iomem *base;
141 int irq;
142};
143
144static irqreturn_t sunxi_rtc_alarmirq(int irq, void *id)
145{
146 struct sunxi_rtc_dev *chip = (struct sunxi_rtc_dev *) id;
147 u32 val;
148
149 val = readl(chip->base + SUNXI_ALRM_IRQ_STA);
150
151 if (val & SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND) {
152 val |= SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND;
153 writel(val, chip->base + SUNXI_ALRM_IRQ_STA);
154
155 rtc_update_irq(chip->rtc, 1, RTC_AF | RTC_IRQF);
156
157 return IRQ_HANDLED;
158 }
159
160 return IRQ_NONE;
161}
162
163static void sunxi_rtc_setaie(unsigned int to, struct sunxi_rtc_dev *chip)
164{
165 u32 alrm_val = 0;
166 u32 alrm_irq_val = 0;
167
168 if (to) {
169 alrm_val = readl(chip->base + SUNXI_ALRM_EN);
170 alrm_val |= SUNXI_ALRM_EN_CNT_EN;
171
172 alrm_irq_val = readl(chip->base + SUNXI_ALRM_IRQ_EN);
173 alrm_irq_val |= SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN;
174 } else {
175 writel(SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND,
176 chip->base + SUNXI_ALRM_IRQ_STA);
177 }
178
179 writel(alrm_val, chip->base + SUNXI_ALRM_EN);
180 writel(alrm_irq_val, chip->base + SUNXI_ALRM_IRQ_EN);
181}
182
183static int sunxi_rtc_getalarm(struct device *dev, struct rtc_wkalrm *wkalrm)
184{
185 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
186 struct rtc_time *alrm_tm = &wkalrm->time;
187 u32 alrm;
188 u32 alrm_en;
189 u32 date;
190
191 alrm = readl(chip->base + SUNXI_ALRM_DHMS);
192 date = readl(chip->base + SUNXI_RTC_YMD);
193
194 alrm_tm->tm_sec = SUNXI_ALRM_GET_SEC_VALUE(alrm);
195 alrm_tm->tm_min = SUNXI_ALRM_GET_MIN_VALUE(alrm);
196 alrm_tm->tm_hour = SUNXI_ALRM_GET_HOUR_VALUE(alrm);
197
198 alrm_tm->tm_mday = SUNXI_DATE_GET_DAY_VALUE(date);
199 alrm_tm->tm_mon = SUNXI_DATE_GET_MON_VALUE(date);
200 alrm_tm->tm_year = SUNXI_DATE_GET_YEAR_VALUE(date,
201 chip->data_year->mask);
202
203 alrm_tm->tm_mon -= 1;
204
205 /*
206 * switch from (data_year->min)-relative offset to
207 * a (1900)-relative one
208 */
209 alrm_tm->tm_year += SUNXI_YEAR_OFF(chip->data_year);
210
211 alrm_en = readl(chip->base + SUNXI_ALRM_IRQ_EN);
212 if (alrm_en & SUNXI_ALRM_EN_CNT_EN)
213 wkalrm->enabled = 1;
214
215 return 0;
216}
217
218static int sunxi_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
219{
220 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
221 u32 date, time;
222
223 /*
224 * read again in case it changes
225 */
226 do {
227 date = readl(chip->base + SUNXI_RTC_YMD);
228 time = readl(chip->base + SUNXI_RTC_HMS);
229 } while ((date != readl(chip->base + SUNXI_RTC_YMD)) ||
230 (time != readl(chip->base + SUNXI_RTC_HMS)));
231
232 rtc_tm->tm_sec = SUNXI_TIME_GET_SEC_VALUE(time);
233 rtc_tm->tm_min = SUNXI_TIME_GET_MIN_VALUE(time);
234 rtc_tm->tm_hour = SUNXI_TIME_GET_HOUR_VALUE(time);
235
236 rtc_tm->tm_mday = SUNXI_DATE_GET_DAY_VALUE(date);
237 rtc_tm->tm_mon = SUNXI_DATE_GET_MON_VALUE(date);
238 rtc_tm->tm_year = SUNXI_DATE_GET_YEAR_VALUE(date,
239 chip->data_year->mask);
240
241 rtc_tm->tm_mon -= 1;
242
243 /*
244 * switch from (data_year->min)-relative offset to
245 * a (1900)-relative one
246 */
247 rtc_tm->tm_year += SUNXI_YEAR_OFF(chip->data_year);
248
249 return 0;
250}
251
252static int sunxi_rtc_setalarm(struct device *dev, struct rtc_wkalrm *wkalrm)
253{
254 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
255 struct rtc_time *alrm_tm = &wkalrm->time;
256 struct rtc_time tm_now;
257 u32 alrm;
258 time64_t diff;
259 unsigned long time_gap;
260 unsigned long time_gap_day;
261 unsigned long time_gap_hour;
262 unsigned long time_gap_min;
263 int ret;
264
265 ret = sunxi_rtc_gettime(dev, &tm_now);
266 if (ret < 0) {
267 dev_err(dev, "Error in getting time\n");
268 return -EINVAL;
269 }
270
271 diff = rtc_tm_sub(alrm_tm, &tm_now);
272 if (diff <= 0) {
273 dev_err(dev, "Date to set in the past\n");
274 return -EINVAL;
275 }
276
277 if (diff > 255 * SEC_IN_DAY) {
278 dev_err(dev, "Day must be in the range 0 - 255\n");
279 return -EINVAL;
280 }
281
282 time_gap = diff;
283 time_gap_day = time_gap / SEC_IN_DAY;
284 time_gap -= time_gap_day * SEC_IN_DAY;
285 time_gap_hour = time_gap / SEC_IN_HOUR;
286 time_gap -= time_gap_hour * SEC_IN_HOUR;
287 time_gap_min = time_gap / SEC_IN_MIN;
288 time_gap -= time_gap_min * SEC_IN_MIN;
289
290 sunxi_rtc_setaie(0, chip);
291 writel(0, chip->base + SUNXI_ALRM_DHMS);
292 usleep_range(100, 300);
293
294 alrm = SUNXI_ALRM_SET_SEC_VALUE(time_gap) |
295 SUNXI_ALRM_SET_MIN_VALUE(time_gap_min) |
296 SUNXI_ALRM_SET_HOUR_VALUE(time_gap_hour) |
297 SUNXI_ALRM_SET_DAY_VALUE(time_gap_day);
298 writel(alrm, chip->base + SUNXI_ALRM_DHMS);
299
300 writel(0, chip->base + SUNXI_ALRM_IRQ_EN);
301 writel(SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN, chip->base + SUNXI_ALRM_IRQ_EN);
302
303 sunxi_rtc_setaie(wkalrm->enabled, chip);
304
305 return 0;
306}
307
308static int sunxi_rtc_wait(struct sunxi_rtc_dev *chip, int offset,
309 unsigned int mask, unsigned int ms_timeout)
310{
311 const unsigned long timeout = jiffies + msecs_to_jiffies(ms_timeout);
312 u32 reg;
313
314 do {
315 reg = readl(chip->base + offset);
316 reg &= mask;
317
318 if (reg == mask)
319 return 0;
320
321 } while (time_before(jiffies, timeout));
322
323 return -ETIMEDOUT;
324}
325
326static int sunxi_rtc_settime(struct device *dev, struct rtc_time *rtc_tm)
327{
328 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
329 u32 date = 0;
330 u32 time = 0;
331 unsigned int year;
332
333 /*
334 * the input rtc_tm->tm_year is the offset relative to 1900. We use
335 * the SUNXI_YEAR_OFF macro to rebase it with respect to the min year
336 * allowed by the hardware
337 */
338
339 year = rtc_tm->tm_year + 1900;
340 if (year < chip->data_year->min || year > chip->data_year->max) {
341 dev_err(dev, "rtc only supports year in range %u - %u\n",
342 chip->data_year->min, chip->data_year->max);
343 return -EINVAL;
344 }
345
346 rtc_tm->tm_year -= SUNXI_YEAR_OFF(chip->data_year);
347 rtc_tm->tm_mon += 1;
348
349 date = SUNXI_DATE_SET_DAY_VALUE(rtc_tm->tm_mday) |
350 SUNXI_DATE_SET_MON_VALUE(rtc_tm->tm_mon) |
351 SUNXI_DATE_SET_YEAR_VALUE(rtc_tm->tm_year,
352 chip->data_year->mask);
353
354 if (is_leap_year(year))
355 date |= SUNXI_LEAP_SET_VALUE(1, chip->data_year->leap_shift);
356
357 time = SUNXI_TIME_SET_SEC_VALUE(rtc_tm->tm_sec) |
358 SUNXI_TIME_SET_MIN_VALUE(rtc_tm->tm_min) |
359 SUNXI_TIME_SET_HOUR_VALUE(rtc_tm->tm_hour);
360
361 writel(0, chip->base + SUNXI_RTC_HMS);
362 writel(0, chip->base + SUNXI_RTC_YMD);
363
364 writel(time, chip->base + SUNXI_RTC_HMS);
365
366 /*
367 * After writing the RTC HH-MM-SS register, the
368 * SUNXI_LOSC_CTRL_RTC_HMS_ACC bit is set and it will not
369 * be cleared until the real writing operation is finished
370 */
371
372 if (sunxi_rtc_wait(chip, SUNXI_LOSC_CTRL,
373 SUNXI_LOSC_CTRL_RTC_HMS_ACC, 50)) {
374 dev_err(dev, "Failed to set rtc time.\n");
375 return -1;
376 }
377
378 writel(date, chip->base + SUNXI_RTC_YMD);
379
380 /*
381 * After writing the RTC YY-MM-DD register, the
382 * SUNXI_LOSC_CTRL_RTC_YMD_ACC bit is set and it will not
383 * be cleared until the real writing operation is finished
384 */
385
386 if (sunxi_rtc_wait(chip, SUNXI_LOSC_CTRL,
387 SUNXI_LOSC_CTRL_RTC_YMD_ACC, 50)) {
388 dev_err(dev, "Failed to set rtc time.\n");
389 return -1;
390 }
391
392 return 0;
393}
394
395static int sunxi_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
396{
397 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
398
399 if (!enabled)
400 sunxi_rtc_setaie(enabled, chip);
401
402 return 0;
403}
404
405static const struct rtc_class_ops sunxi_rtc_ops = {
406 .read_time = sunxi_rtc_gettime,
407 .set_time = sunxi_rtc_settime,
408 .read_alarm = sunxi_rtc_getalarm,
409 .set_alarm = sunxi_rtc_setalarm,
410 .alarm_irq_enable = sunxi_rtc_alarm_irq_enable
411};
412
413static const struct of_device_id sunxi_rtc_dt_ids[] = {
414 { .compatible = "allwinner,sun4i-a10-rtc", .data = &data_year_param[0] },
415 { .compatible = "allwinner,sun7i-a20-rtc", .data = &data_year_param[1] },
416 { /* sentinel */ },
417};
418MODULE_DEVICE_TABLE(of, sunxi_rtc_dt_ids);
419
420static int sunxi_rtc_probe(struct platform_device *pdev)
421{
422 struct sunxi_rtc_dev *chip;
423 int ret;
424
425 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
426 if (!chip)
427 return -ENOMEM;
428
429 platform_set_drvdata(pdev, chip);
430 chip->dev = &pdev->dev;
431
432 chip->rtc = devm_rtc_allocate_device(&pdev->dev);
433 if (IS_ERR(chip->rtc))
434 return PTR_ERR(chip->rtc);
435
436 chip->base = devm_platform_ioremap_resource(pdev, 0);
437 if (IS_ERR(chip->base))
438 return PTR_ERR(chip->base);
439
440 chip->irq = platform_get_irq(pdev, 0);
441 if (chip->irq < 0)
442 return chip->irq;
443 ret = devm_request_irq(&pdev->dev, chip->irq, sunxi_rtc_alarmirq,
444 0, dev_name(&pdev->dev), chip);
445 if (ret) {
446 dev_err(&pdev->dev, "Could not request IRQ\n");
447 return ret;
448 }
449
450 chip->data_year = of_device_get_match_data(&pdev->dev);
451 if (!chip->data_year) {
452 dev_err(&pdev->dev, "Unable to setup RTC data\n");
453 return -ENODEV;
454 }
455
456 /* clear the alarm count value */
457 writel(0, chip->base + SUNXI_ALRM_DHMS);
458
459 /* disable alarm, not generate irq pending */
460 writel(0, chip->base + SUNXI_ALRM_EN);
461
462 /* disable alarm week/cnt irq, unset to cpu */
463 writel(0, chip->base + SUNXI_ALRM_IRQ_EN);
464
465 /* clear alarm week/cnt irq pending */
466 writel(SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND, chip->base +
467 SUNXI_ALRM_IRQ_STA);
468
469 chip->rtc->ops = &sunxi_rtc_ops;
470
471 return devm_rtc_register_device(chip->rtc);
472}
473
474static struct platform_driver sunxi_rtc_driver = {
475 .probe = sunxi_rtc_probe,
476 .driver = {
477 .name = "sunxi-rtc",
478 .of_match_table = sunxi_rtc_dt_ids,
479 },
480};
481
482module_platform_driver(sunxi_rtc_driver);
483
484MODULE_DESCRIPTION("sunxi RTC driver");
485MODULE_AUTHOR("Carlo Caione <carlo.caione@gmail.com>");
486MODULE_LICENSE("GPL");
1/*
2 * An RTC driver for Allwinner A10/A20
3 *
4 * Copyright (c) 2013, Carlo Caione <carlo.caione@gmail.com>
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, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * more details.
15 *
16 * You should have received a copy of the GNU General Public License along
17 * with this program; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
19 */
20
21#include <linux/delay.h>
22#include <linux/err.h>
23#include <linux/fs.h>
24#include <linux/init.h>
25#include <linux/interrupt.h>
26#include <linux/io.h>
27#include <linux/kernel.h>
28#include <linux/module.h>
29#include <linux/of.h>
30#include <linux/of_address.h>
31#include <linux/of_device.h>
32#include <linux/platform_device.h>
33#include <linux/rtc.h>
34#include <linux/types.h>
35
36#define SUNXI_LOSC_CTRL 0x0000
37#define SUNXI_LOSC_CTRL_RTC_HMS_ACC BIT(8)
38#define SUNXI_LOSC_CTRL_RTC_YMD_ACC BIT(7)
39
40#define SUNXI_RTC_YMD 0x0004
41
42#define SUNXI_RTC_HMS 0x0008
43
44#define SUNXI_ALRM_DHMS 0x000c
45
46#define SUNXI_ALRM_EN 0x0014
47#define SUNXI_ALRM_EN_CNT_EN BIT(8)
48
49#define SUNXI_ALRM_IRQ_EN 0x0018
50#define SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN BIT(0)
51
52#define SUNXI_ALRM_IRQ_STA 0x001c
53#define SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND BIT(0)
54
55#define SUNXI_MASK_DH 0x0000001f
56#define SUNXI_MASK_SM 0x0000003f
57#define SUNXI_MASK_M 0x0000000f
58#define SUNXI_MASK_LY 0x00000001
59#define SUNXI_MASK_D 0x00000ffe
60#define SUNXI_MASK_M 0x0000000f
61
62#define SUNXI_GET(x, mask, shift) (((x) & ((mask) << (shift))) \
63 >> (shift))
64
65#define SUNXI_SET(x, mask, shift) (((x) & (mask)) << (shift))
66
67/*
68 * Get date values
69 */
70#define SUNXI_DATE_GET_DAY_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 0)
71#define SUNXI_DATE_GET_MON_VALUE(x) SUNXI_GET(x, SUNXI_MASK_M, 8)
72#define SUNXI_DATE_GET_YEAR_VALUE(x, mask) SUNXI_GET(x, mask, 16)
73
74/*
75 * Get time values
76 */
77#define SUNXI_TIME_GET_SEC_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 0)
78#define SUNXI_TIME_GET_MIN_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 8)
79#define SUNXI_TIME_GET_HOUR_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 16)
80
81/*
82 * Get alarm values
83 */
84#define SUNXI_ALRM_GET_SEC_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 0)
85#define SUNXI_ALRM_GET_MIN_VALUE(x) SUNXI_GET(x, SUNXI_MASK_SM, 8)
86#define SUNXI_ALRM_GET_HOUR_VALUE(x) SUNXI_GET(x, SUNXI_MASK_DH, 16)
87
88/*
89 * Set date values
90 */
91#define SUNXI_DATE_SET_DAY_VALUE(x) SUNXI_DATE_GET_DAY_VALUE(x)
92#define SUNXI_DATE_SET_MON_VALUE(x) SUNXI_SET(x, SUNXI_MASK_M, 8)
93#define SUNXI_DATE_SET_YEAR_VALUE(x, mask) SUNXI_SET(x, mask, 16)
94#define SUNXI_LEAP_SET_VALUE(x, shift) SUNXI_SET(x, SUNXI_MASK_LY, shift)
95
96/*
97 * Set time values
98 */
99#define SUNXI_TIME_SET_SEC_VALUE(x) SUNXI_TIME_GET_SEC_VALUE(x)
100#define SUNXI_TIME_SET_MIN_VALUE(x) SUNXI_SET(x, SUNXI_MASK_SM, 8)
101#define SUNXI_TIME_SET_HOUR_VALUE(x) SUNXI_SET(x, SUNXI_MASK_DH, 16)
102
103/*
104 * Set alarm values
105 */
106#define SUNXI_ALRM_SET_SEC_VALUE(x) SUNXI_ALRM_GET_SEC_VALUE(x)
107#define SUNXI_ALRM_SET_MIN_VALUE(x) SUNXI_SET(x, SUNXI_MASK_SM, 8)
108#define SUNXI_ALRM_SET_HOUR_VALUE(x) SUNXI_SET(x, SUNXI_MASK_DH, 16)
109#define SUNXI_ALRM_SET_DAY_VALUE(x) SUNXI_SET(x, SUNXI_MASK_D, 21)
110
111/*
112 * Time unit conversions
113 */
114#define SEC_IN_MIN 60
115#define SEC_IN_HOUR (60 * SEC_IN_MIN)
116#define SEC_IN_DAY (24 * SEC_IN_HOUR)
117
118/*
119 * The year parameter passed to the driver is usually an offset relative to
120 * the year 1900. This macro is used to convert this offset to another one
121 * relative to the minimum year allowed by the hardware.
122 */
123#define SUNXI_YEAR_OFF(x) ((x)->min - 1900)
124
125/*
126 * min and max year are arbitrary set considering the limited range of the
127 * hardware register field
128 */
129struct sunxi_rtc_data_year {
130 unsigned int min; /* min year allowed */
131 unsigned int max; /* max year allowed */
132 unsigned int mask; /* mask for the year field */
133 unsigned char leap_shift; /* bit shift to get the leap year */
134};
135
136static const struct sunxi_rtc_data_year data_year_param[] = {
137 [0] = {
138 .min = 2010,
139 .max = 2073,
140 .mask = 0x3f,
141 .leap_shift = 22,
142 },
143 [1] = {
144 .min = 1970,
145 .max = 2225,
146 .mask = 0xff,
147 .leap_shift = 24,
148 },
149};
150
151struct sunxi_rtc_dev {
152 struct rtc_device *rtc;
153 struct device *dev;
154 const struct sunxi_rtc_data_year *data_year;
155 void __iomem *base;
156 int irq;
157};
158
159static irqreturn_t sunxi_rtc_alarmirq(int irq, void *id)
160{
161 struct sunxi_rtc_dev *chip = (struct sunxi_rtc_dev *) id;
162 u32 val;
163
164 val = readl(chip->base + SUNXI_ALRM_IRQ_STA);
165
166 if (val & SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND) {
167 val |= SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND;
168 writel(val, chip->base + SUNXI_ALRM_IRQ_STA);
169
170 rtc_update_irq(chip->rtc, 1, RTC_AF | RTC_IRQF);
171
172 return IRQ_HANDLED;
173 }
174
175 return IRQ_NONE;
176}
177
178static void sunxi_rtc_setaie(unsigned int to, struct sunxi_rtc_dev *chip)
179{
180 u32 alrm_val = 0;
181 u32 alrm_irq_val = 0;
182
183 if (to) {
184 alrm_val = readl(chip->base + SUNXI_ALRM_EN);
185 alrm_val |= SUNXI_ALRM_EN_CNT_EN;
186
187 alrm_irq_val = readl(chip->base + SUNXI_ALRM_IRQ_EN);
188 alrm_irq_val |= SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN;
189 } else {
190 writel(SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND,
191 chip->base + SUNXI_ALRM_IRQ_STA);
192 }
193
194 writel(alrm_val, chip->base + SUNXI_ALRM_EN);
195 writel(alrm_irq_val, chip->base + SUNXI_ALRM_IRQ_EN);
196}
197
198static int sunxi_rtc_getalarm(struct device *dev, struct rtc_wkalrm *wkalrm)
199{
200 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
201 struct rtc_time *alrm_tm = &wkalrm->time;
202 u32 alrm;
203 u32 alrm_en;
204 u32 date;
205
206 alrm = readl(chip->base + SUNXI_ALRM_DHMS);
207 date = readl(chip->base + SUNXI_RTC_YMD);
208
209 alrm_tm->tm_sec = SUNXI_ALRM_GET_SEC_VALUE(alrm);
210 alrm_tm->tm_min = SUNXI_ALRM_GET_MIN_VALUE(alrm);
211 alrm_tm->tm_hour = SUNXI_ALRM_GET_HOUR_VALUE(alrm);
212
213 alrm_tm->tm_mday = SUNXI_DATE_GET_DAY_VALUE(date);
214 alrm_tm->tm_mon = SUNXI_DATE_GET_MON_VALUE(date);
215 alrm_tm->tm_year = SUNXI_DATE_GET_YEAR_VALUE(date,
216 chip->data_year->mask);
217
218 alrm_tm->tm_mon -= 1;
219
220 /*
221 * switch from (data_year->min)-relative offset to
222 * a (1900)-relative one
223 */
224 alrm_tm->tm_year += SUNXI_YEAR_OFF(chip->data_year);
225
226 alrm_en = readl(chip->base + SUNXI_ALRM_IRQ_EN);
227 if (alrm_en & SUNXI_ALRM_EN_CNT_EN)
228 wkalrm->enabled = 1;
229
230 return 0;
231}
232
233static int sunxi_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
234{
235 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
236 u32 date, time;
237
238 /*
239 * read again in case it changes
240 */
241 do {
242 date = readl(chip->base + SUNXI_RTC_YMD);
243 time = readl(chip->base + SUNXI_RTC_HMS);
244 } while ((date != readl(chip->base + SUNXI_RTC_YMD)) ||
245 (time != readl(chip->base + SUNXI_RTC_HMS)));
246
247 rtc_tm->tm_sec = SUNXI_TIME_GET_SEC_VALUE(time);
248 rtc_tm->tm_min = SUNXI_TIME_GET_MIN_VALUE(time);
249 rtc_tm->tm_hour = SUNXI_TIME_GET_HOUR_VALUE(time);
250
251 rtc_tm->tm_mday = SUNXI_DATE_GET_DAY_VALUE(date);
252 rtc_tm->tm_mon = SUNXI_DATE_GET_MON_VALUE(date);
253 rtc_tm->tm_year = SUNXI_DATE_GET_YEAR_VALUE(date,
254 chip->data_year->mask);
255
256 rtc_tm->tm_mon -= 1;
257
258 /*
259 * switch from (data_year->min)-relative offset to
260 * a (1900)-relative one
261 */
262 rtc_tm->tm_year += SUNXI_YEAR_OFF(chip->data_year);
263
264 return rtc_valid_tm(rtc_tm);
265}
266
267static int sunxi_rtc_setalarm(struct device *dev, struct rtc_wkalrm *wkalrm)
268{
269 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
270 struct rtc_time *alrm_tm = &wkalrm->time;
271 struct rtc_time tm_now;
272 u32 alrm;
273 time64_t diff;
274 unsigned long time_gap;
275 unsigned long time_gap_day;
276 unsigned long time_gap_hour;
277 unsigned long time_gap_min;
278 int ret;
279
280 ret = sunxi_rtc_gettime(dev, &tm_now);
281 if (ret < 0) {
282 dev_err(dev, "Error in getting time\n");
283 return -EINVAL;
284 }
285
286 diff = rtc_tm_sub(alrm_tm, &tm_now);
287 if (diff <= 0) {
288 dev_err(dev, "Date to set in the past\n");
289 return -EINVAL;
290 }
291
292 if (diff > 255 * SEC_IN_DAY) {
293 dev_err(dev, "Day must be in the range 0 - 255\n");
294 return -EINVAL;
295 }
296
297 time_gap = diff;
298 time_gap_day = time_gap / SEC_IN_DAY;
299 time_gap -= time_gap_day * SEC_IN_DAY;
300 time_gap_hour = time_gap / SEC_IN_HOUR;
301 time_gap -= time_gap_hour * SEC_IN_HOUR;
302 time_gap_min = time_gap / SEC_IN_MIN;
303 time_gap -= time_gap_min * SEC_IN_MIN;
304
305 sunxi_rtc_setaie(0, chip);
306 writel(0, chip->base + SUNXI_ALRM_DHMS);
307 usleep_range(100, 300);
308
309 alrm = SUNXI_ALRM_SET_SEC_VALUE(time_gap) |
310 SUNXI_ALRM_SET_MIN_VALUE(time_gap_min) |
311 SUNXI_ALRM_SET_HOUR_VALUE(time_gap_hour) |
312 SUNXI_ALRM_SET_DAY_VALUE(time_gap_day);
313 writel(alrm, chip->base + SUNXI_ALRM_DHMS);
314
315 writel(0, chip->base + SUNXI_ALRM_IRQ_EN);
316 writel(SUNXI_ALRM_IRQ_EN_CNT_IRQ_EN, chip->base + SUNXI_ALRM_IRQ_EN);
317
318 sunxi_rtc_setaie(wkalrm->enabled, chip);
319
320 return 0;
321}
322
323static int sunxi_rtc_wait(struct sunxi_rtc_dev *chip, int offset,
324 unsigned int mask, unsigned int ms_timeout)
325{
326 const unsigned long timeout = jiffies + msecs_to_jiffies(ms_timeout);
327 u32 reg;
328
329 do {
330 reg = readl(chip->base + offset);
331 reg &= mask;
332
333 if (reg == mask)
334 return 0;
335
336 } while (time_before(jiffies, timeout));
337
338 return -ETIMEDOUT;
339}
340
341static int sunxi_rtc_settime(struct device *dev, struct rtc_time *rtc_tm)
342{
343 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
344 u32 date = 0;
345 u32 time = 0;
346 unsigned int year;
347
348 /*
349 * the input rtc_tm->tm_year is the offset relative to 1900. We use
350 * the SUNXI_YEAR_OFF macro to rebase it with respect to the min year
351 * allowed by the hardware
352 */
353
354 year = rtc_tm->tm_year + 1900;
355 if (year < chip->data_year->min || year > chip->data_year->max) {
356 dev_err(dev, "rtc only supports year in range %u - %u\n",
357 chip->data_year->min, chip->data_year->max);
358 return -EINVAL;
359 }
360
361 rtc_tm->tm_year -= SUNXI_YEAR_OFF(chip->data_year);
362 rtc_tm->tm_mon += 1;
363
364 date = SUNXI_DATE_SET_DAY_VALUE(rtc_tm->tm_mday) |
365 SUNXI_DATE_SET_MON_VALUE(rtc_tm->tm_mon) |
366 SUNXI_DATE_SET_YEAR_VALUE(rtc_tm->tm_year,
367 chip->data_year->mask);
368
369 if (is_leap_year(year))
370 date |= SUNXI_LEAP_SET_VALUE(1, chip->data_year->leap_shift);
371
372 time = SUNXI_TIME_SET_SEC_VALUE(rtc_tm->tm_sec) |
373 SUNXI_TIME_SET_MIN_VALUE(rtc_tm->tm_min) |
374 SUNXI_TIME_SET_HOUR_VALUE(rtc_tm->tm_hour);
375
376 writel(0, chip->base + SUNXI_RTC_HMS);
377 writel(0, chip->base + SUNXI_RTC_YMD);
378
379 writel(time, chip->base + SUNXI_RTC_HMS);
380
381 /*
382 * After writing the RTC HH-MM-SS register, the
383 * SUNXI_LOSC_CTRL_RTC_HMS_ACC bit is set and it will not
384 * be cleared until the real writing operation is finished
385 */
386
387 if (sunxi_rtc_wait(chip, SUNXI_LOSC_CTRL,
388 SUNXI_LOSC_CTRL_RTC_HMS_ACC, 50)) {
389 dev_err(dev, "Failed to set rtc time.\n");
390 return -1;
391 }
392
393 writel(date, chip->base + SUNXI_RTC_YMD);
394
395 /*
396 * After writing the RTC YY-MM-DD register, the
397 * SUNXI_LOSC_CTRL_RTC_YMD_ACC bit is set and it will not
398 * be cleared until the real writing operation is finished
399 */
400
401 if (sunxi_rtc_wait(chip, SUNXI_LOSC_CTRL,
402 SUNXI_LOSC_CTRL_RTC_YMD_ACC, 50)) {
403 dev_err(dev, "Failed to set rtc time.\n");
404 return -1;
405 }
406
407 return 0;
408}
409
410static int sunxi_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
411{
412 struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
413
414 if (!enabled)
415 sunxi_rtc_setaie(enabled, chip);
416
417 return 0;
418}
419
420static const struct rtc_class_ops sunxi_rtc_ops = {
421 .read_time = sunxi_rtc_gettime,
422 .set_time = sunxi_rtc_settime,
423 .read_alarm = sunxi_rtc_getalarm,
424 .set_alarm = sunxi_rtc_setalarm,
425 .alarm_irq_enable = sunxi_rtc_alarm_irq_enable
426};
427
428static const struct of_device_id sunxi_rtc_dt_ids[] = {
429 { .compatible = "allwinner,sun4i-a10-rtc", .data = &data_year_param[0] },
430 { .compatible = "allwinner,sun7i-a20-rtc", .data = &data_year_param[1] },
431 { /* sentinel */ },
432};
433MODULE_DEVICE_TABLE(of, sunxi_rtc_dt_ids);
434
435static int sunxi_rtc_probe(struct platform_device *pdev)
436{
437 struct sunxi_rtc_dev *chip;
438 struct resource *res;
439 int ret;
440
441 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
442 if (!chip)
443 return -ENOMEM;
444
445 platform_set_drvdata(pdev, chip);
446 chip->dev = &pdev->dev;
447
448 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
449 chip->base = devm_ioremap_resource(&pdev->dev, res);
450 if (IS_ERR(chip->base))
451 return PTR_ERR(chip->base);
452
453 chip->irq = platform_get_irq(pdev, 0);
454 if (chip->irq < 0) {
455 dev_err(&pdev->dev, "No IRQ resource\n");
456 return chip->irq;
457 }
458 ret = devm_request_irq(&pdev->dev, chip->irq, sunxi_rtc_alarmirq,
459 0, dev_name(&pdev->dev), chip);
460 if (ret) {
461 dev_err(&pdev->dev, "Could not request IRQ\n");
462 return ret;
463 }
464
465 chip->data_year = of_device_get_match_data(&pdev->dev);
466 if (!chip->data_year) {
467 dev_err(&pdev->dev, "Unable to setup RTC data\n");
468 return -ENODEV;
469 }
470
471 /* clear the alarm count value */
472 writel(0, chip->base + SUNXI_ALRM_DHMS);
473
474 /* disable alarm, not generate irq pending */
475 writel(0, chip->base + SUNXI_ALRM_EN);
476
477 /* disable alarm week/cnt irq, unset to cpu */
478 writel(0, chip->base + SUNXI_ALRM_IRQ_EN);
479
480 /* clear alarm week/cnt irq pending */
481 writel(SUNXI_ALRM_IRQ_STA_CNT_IRQ_PEND, chip->base +
482 SUNXI_ALRM_IRQ_STA);
483
484 chip->rtc = rtc_device_register("rtc-sunxi", &pdev->dev,
485 &sunxi_rtc_ops, THIS_MODULE);
486 if (IS_ERR(chip->rtc)) {
487 dev_err(&pdev->dev, "unable to register device\n");
488 return PTR_ERR(chip->rtc);
489 }
490
491 dev_info(&pdev->dev, "RTC enabled\n");
492
493 return 0;
494}
495
496static int sunxi_rtc_remove(struct platform_device *pdev)
497{
498 struct sunxi_rtc_dev *chip = platform_get_drvdata(pdev);
499
500 rtc_device_unregister(chip->rtc);
501
502 return 0;
503}
504
505static struct platform_driver sunxi_rtc_driver = {
506 .probe = sunxi_rtc_probe,
507 .remove = sunxi_rtc_remove,
508 .driver = {
509 .name = "sunxi-rtc",
510 .of_match_table = sunxi_rtc_dt_ids,
511 },
512};
513
514module_platform_driver(sunxi_rtc_driver);
515
516MODULE_DESCRIPTION("sunxi RTC driver");
517MODULE_AUTHOR("Carlo Caione <carlo.caione@gmail.com>");
518MODULE_LICENSE("GPL");