]>
Commit | Line | Data |
---|---|---|
9765d2d9 CYT |
1 | /* |
2 | * An RTC driver for Allwinner A31/A23 | |
3 | * | |
4 | * Copyright (c) 2014, Chen-Yu Tsai <wens@csie.org> | |
5 | * | |
6 | * based on rtc-sunxi.c | |
7 | * | |
8 | * An RTC driver for Allwinner A10/A20 | |
9 | * | |
10 | * Copyright (c) 2013, Carlo Caione <carlo.caione@gmail.com> | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License as published by | |
14 | * the Free Software Foundation; either version 2 of the License, or | |
15 | * (at your option) any later version. | |
16 | * | |
17 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
18 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
19 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
20 | * more details. | |
21 | */ | |
22 | ||
23 | #include <linux/delay.h> | |
24 | #include <linux/err.h> | |
25 | #include <linux/fs.h> | |
26 | #include <linux/init.h> | |
27 | #include <linux/interrupt.h> | |
28 | #include <linux/io.h> | |
29 | #include <linux/kernel.h> | |
30 | #include <linux/module.h> | |
31 | #include <linux/of.h> | |
32 | #include <linux/of_address.h> | |
33 | #include <linux/of_device.h> | |
34 | #include <linux/platform_device.h> | |
35 | #include <linux/rtc.h> | |
36 | #include <linux/types.h> | |
37 | ||
38 | /* Control register */ | |
39 | #define SUN6I_LOSC_CTRL 0x0000 | |
3acb0460 | 40 | #define SUN6I_LOSC_CTRL_KEY (0x16aa << 16) |
9765d2d9 CYT |
41 | #define SUN6I_LOSC_CTRL_ALM_DHMS_ACC BIT(9) |
42 | #define SUN6I_LOSC_CTRL_RTC_HMS_ACC BIT(8) | |
43 | #define SUN6I_LOSC_CTRL_RTC_YMD_ACC BIT(7) | |
3acb0460 | 44 | #define SUN6I_LOSC_CTRL_EXT_OSC BIT(0) |
9765d2d9 CYT |
45 | #define SUN6I_LOSC_CTRL_ACC_MASK GENMASK(9, 7) |
46 | ||
47 | /* RTC */ | |
48 | #define SUN6I_RTC_YMD 0x0010 | |
49 | #define SUN6I_RTC_HMS 0x0014 | |
50 | ||
51 | /* Alarm 0 (counter) */ | |
52 | #define SUN6I_ALRM_COUNTER 0x0020 | |
53 | #define SUN6I_ALRM_CUR_VAL 0x0024 | |
54 | #define SUN6I_ALRM_EN 0x0028 | |
55 | #define SUN6I_ALRM_EN_CNT_EN BIT(0) | |
56 | #define SUN6I_ALRM_IRQ_EN 0x002c | |
57 | #define SUN6I_ALRM_IRQ_EN_CNT_IRQ_EN BIT(0) | |
58 | #define SUN6I_ALRM_IRQ_STA 0x0030 | |
59 | #define SUN6I_ALRM_IRQ_STA_CNT_IRQ_PEND BIT(0) | |
60 | ||
61 | /* Alarm 1 (wall clock) */ | |
62 | #define SUN6I_ALRM1_EN 0x0044 | |
63 | #define SUN6I_ALRM1_IRQ_EN 0x0048 | |
64 | #define SUN6I_ALRM1_IRQ_STA 0x004c | |
65 | #define SUN6I_ALRM1_IRQ_STA_WEEK_IRQ_PEND BIT(0) | |
66 | ||
67 | /* Alarm config */ | |
68 | #define SUN6I_ALARM_CONFIG 0x0050 | |
69 | #define SUN6I_ALARM_CONFIG_WAKEUP BIT(0) | |
70 | ||
71 | /* | |
72 | * Get date values | |
73 | */ | |
74 | #define SUN6I_DATE_GET_DAY_VALUE(x) ((x) & 0x0000001f) | |
75 | #define SUN6I_DATE_GET_MON_VALUE(x) (((x) & 0x00000f00) >> 8) | |
76 | #define SUN6I_DATE_GET_YEAR_VALUE(x) (((x) & 0x003f0000) >> 16) | |
77 | #define SUN6I_LEAP_GET_VALUE(x) (((x) & 0x00400000) >> 22) | |
78 | ||
79 | /* | |
80 | * Get time values | |
81 | */ | |
82 | #define SUN6I_TIME_GET_SEC_VALUE(x) ((x) & 0x0000003f) | |
83 | #define SUN6I_TIME_GET_MIN_VALUE(x) (((x) & 0x00003f00) >> 8) | |
84 | #define SUN6I_TIME_GET_HOUR_VALUE(x) (((x) & 0x001f0000) >> 16) | |
85 | ||
86 | /* | |
87 | * Set date values | |
88 | */ | |
89 | #define SUN6I_DATE_SET_DAY_VALUE(x) ((x) & 0x0000001f) | |
90 | #define SUN6I_DATE_SET_MON_VALUE(x) ((x) << 8 & 0x00000f00) | |
91 | #define SUN6I_DATE_SET_YEAR_VALUE(x) ((x) << 16 & 0x003f0000) | |
92 | #define SUN6I_LEAP_SET_VALUE(x) ((x) << 22 & 0x00400000) | |
93 | ||
94 | /* | |
95 | * Set time values | |
96 | */ | |
97 | #define SUN6I_TIME_SET_SEC_VALUE(x) ((x) & 0x0000003f) | |
98 | #define SUN6I_TIME_SET_MIN_VALUE(x) ((x) << 8 & 0x00003f00) | |
99 | #define SUN6I_TIME_SET_HOUR_VALUE(x) ((x) << 16 & 0x001f0000) | |
100 | ||
101 | /* | |
102 | * The year parameter passed to the driver is usually an offset relative to | |
103 | * the year 1900. This macro is used to convert this offset to another one | |
104 | * relative to the minimum year allowed by the hardware. | |
105 | * | |
106 | * The year range is 1970 - 2033. This range is selected to match Allwinner's | |
107 | * driver, even though it is somewhat limited. | |
108 | */ | |
109 | #define SUN6I_YEAR_MIN 1970 | |
110 | #define SUN6I_YEAR_MAX 2033 | |
111 | #define SUN6I_YEAR_OFF (SUN6I_YEAR_MIN - 1900) | |
112 | ||
113 | struct sun6i_rtc_dev { | |
114 | struct rtc_device *rtc; | |
115 | struct device *dev; | |
116 | void __iomem *base; | |
117 | int irq; | |
118 | unsigned long alarm; | |
84d9116b MR |
119 | |
120 | spinlock_t lock; | |
9765d2d9 CYT |
121 | }; |
122 | ||
123 | static irqreturn_t sun6i_rtc_alarmirq(int irq, void *id) | |
124 | { | |
125 | struct sun6i_rtc_dev *chip = (struct sun6i_rtc_dev *) id; | |
84d9116b | 126 | irqreturn_t ret = IRQ_NONE; |
9765d2d9 CYT |
127 | u32 val; |
128 | ||
84d9116b | 129 | spin_lock(&chip->lock); |
9765d2d9 CYT |
130 | val = readl(chip->base + SUN6I_ALRM_IRQ_STA); |
131 | ||
132 | if (val & SUN6I_ALRM_IRQ_STA_CNT_IRQ_PEND) { | |
133 | val |= SUN6I_ALRM_IRQ_STA_CNT_IRQ_PEND; | |
134 | writel(val, chip->base + SUN6I_ALRM_IRQ_STA); | |
135 | ||
136 | rtc_update_irq(chip->rtc, 1, RTC_AF | RTC_IRQF); | |
137 | ||
84d9116b | 138 | ret = IRQ_HANDLED; |
9765d2d9 | 139 | } |
84d9116b | 140 | spin_unlock(&chip->lock); |
9765d2d9 | 141 | |
84d9116b | 142 | return ret; |
9765d2d9 CYT |
143 | } |
144 | ||
145 | static void sun6i_rtc_setaie(int to, struct sun6i_rtc_dev *chip) | |
146 | { | |
147 | u32 alrm_val = 0; | |
148 | u32 alrm_irq_val = 0; | |
149 | u32 alrm_wake_val = 0; | |
84d9116b | 150 | unsigned long flags; |
9765d2d9 CYT |
151 | |
152 | if (to) { | |
153 | alrm_val = SUN6I_ALRM_EN_CNT_EN; | |
154 | alrm_irq_val = SUN6I_ALRM_IRQ_EN_CNT_IRQ_EN; | |
155 | alrm_wake_val = SUN6I_ALARM_CONFIG_WAKEUP; | |
156 | } else { | |
157 | writel(SUN6I_ALRM_IRQ_STA_CNT_IRQ_PEND, | |
158 | chip->base + SUN6I_ALRM_IRQ_STA); | |
159 | } | |
160 | ||
84d9116b | 161 | spin_lock_irqsave(&chip->lock, flags); |
9765d2d9 CYT |
162 | writel(alrm_val, chip->base + SUN6I_ALRM_EN); |
163 | writel(alrm_irq_val, chip->base + SUN6I_ALRM_IRQ_EN); | |
164 | writel(alrm_wake_val, chip->base + SUN6I_ALARM_CONFIG); | |
84d9116b | 165 | spin_unlock_irqrestore(&chip->lock, flags); |
9765d2d9 CYT |
166 | } |
167 | ||
168 | static int sun6i_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm) | |
169 | { | |
170 | struct sun6i_rtc_dev *chip = dev_get_drvdata(dev); | |
171 | u32 date, time; | |
172 | ||
173 | /* | |
174 | * read again in case it changes | |
175 | */ | |
176 | do { | |
177 | date = readl(chip->base + SUN6I_RTC_YMD); | |
178 | time = readl(chip->base + SUN6I_RTC_HMS); | |
179 | } while ((date != readl(chip->base + SUN6I_RTC_YMD)) || | |
180 | (time != readl(chip->base + SUN6I_RTC_HMS))); | |
181 | ||
182 | rtc_tm->tm_sec = SUN6I_TIME_GET_SEC_VALUE(time); | |
183 | rtc_tm->tm_min = SUN6I_TIME_GET_MIN_VALUE(time); | |
184 | rtc_tm->tm_hour = SUN6I_TIME_GET_HOUR_VALUE(time); | |
185 | ||
186 | rtc_tm->tm_mday = SUN6I_DATE_GET_DAY_VALUE(date); | |
187 | rtc_tm->tm_mon = SUN6I_DATE_GET_MON_VALUE(date); | |
188 | rtc_tm->tm_year = SUN6I_DATE_GET_YEAR_VALUE(date); | |
189 | ||
190 | rtc_tm->tm_mon -= 1; | |
191 | ||
192 | /* | |
193 | * switch from (data_year->min)-relative offset to | |
194 | * a (1900)-relative one | |
195 | */ | |
196 | rtc_tm->tm_year += SUN6I_YEAR_OFF; | |
197 | ||
198 | return rtc_valid_tm(rtc_tm); | |
199 | } | |
200 | ||
201 | static int sun6i_rtc_getalarm(struct device *dev, struct rtc_wkalrm *wkalrm) | |
202 | { | |
203 | struct sun6i_rtc_dev *chip = dev_get_drvdata(dev); | |
84d9116b | 204 | unsigned long flags; |
9765d2d9 CYT |
205 | u32 alrm_st; |
206 | u32 alrm_en; | |
207 | ||
84d9116b | 208 | spin_lock_irqsave(&chip->lock, flags); |
9765d2d9 CYT |
209 | alrm_en = readl(chip->base + SUN6I_ALRM_IRQ_EN); |
210 | alrm_st = readl(chip->base + SUN6I_ALRM_IRQ_STA); | |
84d9116b MR |
211 | spin_unlock_irqrestore(&chip->lock, flags); |
212 | ||
9765d2d9 CYT |
213 | wkalrm->enabled = !!(alrm_en & SUN6I_ALRM_EN_CNT_EN); |
214 | wkalrm->pending = !!(alrm_st & SUN6I_ALRM_EN_CNT_EN); | |
215 | rtc_time_to_tm(chip->alarm, &wkalrm->time); | |
216 | ||
217 | return 0; | |
218 | } | |
219 | ||
220 | static int sun6i_rtc_setalarm(struct device *dev, struct rtc_wkalrm *wkalrm) | |
221 | { | |
222 | struct sun6i_rtc_dev *chip = dev_get_drvdata(dev); | |
223 | struct rtc_time *alrm_tm = &wkalrm->time; | |
224 | struct rtc_time tm_now; | |
225 | unsigned long time_now = 0; | |
226 | unsigned long time_set = 0; | |
227 | unsigned long time_gap = 0; | |
228 | int ret = 0; | |
229 | ||
230 | ret = sun6i_rtc_gettime(dev, &tm_now); | |
231 | if (ret < 0) { | |
232 | dev_err(dev, "Error in getting time\n"); | |
233 | return -EINVAL; | |
234 | } | |
235 | ||
236 | rtc_tm_to_time(alrm_tm, &time_set); | |
237 | rtc_tm_to_time(&tm_now, &time_now); | |
238 | if (time_set <= time_now) { | |
239 | dev_err(dev, "Date to set in the past\n"); | |
240 | return -EINVAL; | |
241 | } | |
242 | ||
243 | time_gap = time_set - time_now; | |
244 | ||
245 | if (time_gap > U32_MAX) { | |
246 | dev_err(dev, "Date too far in the future\n"); | |
247 | return -EINVAL; | |
248 | } | |
249 | ||
250 | sun6i_rtc_setaie(0, chip); | |
251 | writel(0, chip->base + SUN6I_ALRM_COUNTER); | |
252 | usleep_range(100, 300); | |
253 | ||
254 | writel(time_gap, chip->base + SUN6I_ALRM_COUNTER); | |
255 | chip->alarm = time_set; | |
256 | ||
257 | sun6i_rtc_setaie(wkalrm->enabled, chip); | |
258 | ||
259 | return 0; | |
260 | } | |
261 | ||
262 | static int sun6i_rtc_wait(struct sun6i_rtc_dev *chip, int offset, | |
263 | unsigned int mask, unsigned int ms_timeout) | |
264 | { | |
265 | const unsigned long timeout = jiffies + msecs_to_jiffies(ms_timeout); | |
266 | u32 reg; | |
267 | ||
268 | do { | |
269 | reg = readl(chip->base + offset); | |
270 | reg &= mask; | |
271 | ||
272 | if (!reg) | |
273 | return 0; | |
274 | ||
275 | } while (time_before(jiffies, timeout)); | |
276 | ||
277 | return -ETIMEDOUT; | |
278 | } | |
279 | ||
280 | static int sun6i_rtc_settime(struct device *dev, struct rtc_time *rtc_tm) | |
281 | { | |
282 | struct sun6i_rtc_dev *chip = dev_get_drvdata(dev); | |
283 | u32 date = 0; | |
284 | u32 time = 0; | |
285 | int year; | |
286 | ||
287 | year = rtc_tm->tm_year + 1900; | |
288 | if (year < SUN6I_YEAR_MIN || year > SUN6I_YEAR_MAX) { | |
289 | dev_err(dev, "rtc only supports year in range %d - %d\n", | |
290 | SUN6I_YEAR_MIN, SUN6I_YEAR_MAX); | |
291 | return -EINVAL; | |
292 | } | |
293 | ||
294 | rtc_tm->tm_year -= SUN6I_YEAR_OFF; | |
295 | rtc_tm->tm_mon += 1; | |
296 | ||
297 | date = SUN6I_DATE_SET_DAY_VALUE(rtc_tm->tm_mday) | | |
298 | SUN6I_DATE_SET_MON_VALUE(rtc_tm->tm_mon) | | |
299 | SUN6I_DATE_SET_YEAR_VALUE(rtc_tm->tm_year); | |
300 | ||
301 | if (is_leap_year(year)) | |
302 | date |= SUN6I_LEAP_SET_VALUE(1); | |
303 | ||
304 | time = SUN6I_TIME_SET_SEC_VALUE(rtc_tm->tm_sec) | | |
305 | SUN6I_TIME_SET_MIN_VALUE(rtc_tm->tm_min) | | |
306 | SUN6I_TIME_SET_HOUR_VALUE(rtc_tm->tm_hour); | |
307 | ||
308 | /* Check whether registers are writable */ | |
309 | if (sun6i_rtc_wait(chip, SUN6I_LOSC_CTRL, | |
310 | SUN6I_LOSC_CTRL_ACC_MASK, 50)) { | |
311 | dev_err(dev, "rtc is still busy.\n"); | |
312 | return -EBUSY; | |
313 | } | |
314 | ||
315 | writel(time, chip->base + SUN6I_RTC_HMS); | |
316 | ||
317 | /* | |
318 | * After writing the RTC HH-MM-SS register, the | |
319 | * SUN6I_LOSC_CTRL_RTC_HMS_ACC bit is set and it will not | |
320 | * be cleared until the real writing operation is finished | |
321 | */ | |
322 | ||
323 | if (sun6i_rtc_wait(chip, SUN6I_LOSC_CTRL, | |
324 | SUN6I_LOSC_CTRL_RTC_HMS_ACC, 50)) { | |
325 | dev_err(dev, "Failed to set rtc time.\n"); | |
326 | return -ETIMEDOUT; | |
327 | } | |
328 | ||
329 | writel(date, chip->base + SUN6I_RTC_YMD); | |
330 | ||
331 | /* | |
332 | * After writing the RTC YY-MM-DD register, the | |
333 | * SUN6I_LOSC_CTRL_RTC_YMD_ACC bit is set and it will not | |
334 | * be cleared until the real writing operation is finished | |
335 | */ | |
336 | ||
337 | if (sun6i_rtc_wait(chip, SUN6I_LOSC_CTRL, | |
338 | SUN6I_LOSC_CTRL_RTC_YMD_ACC, 50)) { | |
339 | dev_err(dev, "Failed to set rtc time.\n"); | |
340 | return -ETIMEDOUT; | |
341 | } | |
342 | ||
343 | return 0; | |
344 | } | |
345 | ||
346 | static int sun6i_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) | |
347 | { | |
348 | struct sun6i_rtc_dev *chip = dev_get_drvdata(dev); | |
349 | ||
350 | if (!enabled) | |
351 | sun6i_rtc_setaie(enabled, chip); | |
352 | ||
353 | return 0; | |
354 | } | |
355 | ||
356 | static const struct rtc_class_ops sun6i_rtc_ops = { | |
357 | .read_time = sun6i_rtc_gettime, | |
358 | .set_time = sun6i_rtc_settime, | |
359 | .read_alarm = sun6i_rtc_getalarm, | |
360 | .set_alarm = sun6i_rtc_setalarm, | |
361 | .alarm_irq_enable = sun6i_rtc_alarm_irq_enable | |
362 | }; | |
363 | ||
364 | static int sun6i_rtc_probe(struct platform_device *pdev) | |
365 | { | |
366 | struct sun6i_rtc_dev *chip; | |
367 | struct resource *res; | |
368 | int ret; | |
369 | ||
370 | chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL); | |
371 | if (!chip) | |
372 | return -ENOMEM; | |
84d9116b | 373 | spin_lock_init(&chip->lock); |
9765d2d9 CYT |
374 | |
375 | platform_set_drvdata(pdev, chip); | |
376 | chip->dev = &pdev->dev; | |
377 | ||
378 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
379 | chip->base = devm_ioremap_resource(&pdev->dev, res); | |
380 | if (IS_ERR(chip->base)) | |
381 | return PTR_ERR(chip->base); | |
382 | ||
383 | chip->irq = platform_get_irq(pdev, 0); | |
384 | if (chip->irq < 0) { | |
385 | dev_err(&pdev->dev, "No IRQ resource\n"); | |
386 | return chip->irq; | |
387 | } | |
388 | ||
389 | ret = devm_request_irq(&pdev->dev, chip->irq, sun6i_rtc_alarmirq, | |
390 | 0, dev_name(&pdev->dev), chip); | |
391 | if (ret) { | |
392 | dev_err(&pdev->dev, "Could not request IRQ\n"); | |
393 | return ret; | |
394 | } | |
395 | ||
396 | /* clear the alarm counter value */ | |
397 | writel(0, chip->base + SUN6I_ALRM_COUNTER); | |
398 | ||
399 | /* disable counter alarm */ | |
400 | writel(0, chip->base + SUN6I_ALRM_EN); | |
401 | ||
402 | /* disable counter alarm interrupt */ | |
403 | writel(0, chip->base + SUN6I_ALRM_IRQ_EN); | |
404 | ||
405 | /* disable week alarm */ | |
406 | writel(0, chip->base + SUN6I_ALRM1_EN); | |
407 | ||
408 | /* disable week alarm interrupt */ | |
409 | writel(0, chip->base + SUN6I_ALRM1_IRQ_EN); | |
410 | ||
411 | /* clear counter alarm pending interrupts */ | |
412 | writel(SUN6I_ALRM_IRQ_STA_CNT_IRQ_PEND, | |
413 | chip->base + SUN6I_ALRM_IRQ_STA); | |
414 | ||
415 | /* clear week alarm pending interrupts */ | |
416 | writel(SUN6I_ALRM1_IRQ_STA_WEEK_IRQ_PEND, | |
417 | chip->base + SUN6I_ALRM1_IRQ_STA); | |
418 | ||
419 | /* disable alarm wakeup */ | |
420 | writel(0, chip->base + SUN6I_ALARM_CONFIG); | |
421 | ||
3acb0460 MR |
422 | /* switch to the external, more precise, oscillator */ |
423 | writel(SUN6I_LOSC_CTRL_KEY | SUN6I_LOSC_CTRL_EXT_OSC, | |
424 | chip->base + SUN6I_LOSC_CTRL); | |
425 | ||
9765d2d9 CYT |
426 | chip->rtc = rtc_device_register("rtc-sun6i", &pdev->dev, |
427 | &sun6i_rtc_ops, THIS_MODULE); | |
428 | if (IS_ERR(chip->rtc)) { | |
429 | dev_err(&pdev->dev, "unable to register device\n"); | |
430 | return PTR_ERR(chip->rtc); | |
431 | } | |
432 | ||
433 | dev_info(&pdev->dev, "RTC enabled\n"); | |
434 | ||
435 | return 0; | |
436 | } | |
437 | ||
438 | static int sun6i_rtc_remove(struct platform_device *pdev) | |
439 | { | |
440 | struct sun6i_rtc_dev *chip = platform_get_drvdata(pdev); | |
441 | ||
442 | rtc_device_unregister(chip->rtc); | |
443 | ||
444 | return 0; | |
445 | } | |
446 | ||
447 | static const struct of_device_id sun6i_rtc_dt_ids[] = { | |
448 | { .compatible = "allwinner,sun6i-a31-rtc" }, | |
449 | { /* sentinel */ }, | |
450 | }; | |
451 | MODULE_DEVICE_TABLE(of, sun6i_rtc_dt_ids); | |
452 | ||
453 | static struct platform_driver sun6i_rtc_driver = { | |
454 | .probe = sun6i_rtc_probe, | |
455 | .remove = sun6i_rtc_remove, | |
456 | .driver = { | |
457 | .name = "sun6i-rtc", | |
458 | .of_match_table = sun6i_rtc_dt_ids, | |
459 | }, | |
460 | }; | |
f54edad1 | 461 | builtin_platform_driver(sun6i_rtc_driver); |