xref: /linux/drivers/rtc/rtc-omap.c (revision 80d443e8876602be2c130f79c4de81e12e2a700d)
1 /*
2  * TI OMAP Real Time Clock interface for Linux
3  *
4  * Copyright (C) 2003 MontaVista Software, Inc.
5  * Author: George G. Davis <gdavis@mvista.com> or <source@mvista.com>
6  *
7  * Copyright (C) 2006 David Brownell (new RTC framework)
8  * Copyright (C) 2014 Johan Hovold <johan@kernel.org>
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License
12  * as published by the Free Software Foundation; either version
13  * 2 of the License, or (at your option) any later version.
14  */
15 
16 #include <dt-bindings/gpio/gpio.h>
17 #include <linux/bcd.h>
18 #include <linux/clk.h>
19 #include <linux/delay.h>
20 #include <linux/init.h>
21 #include <linux/io.h>
22 #include <linux/ioport.h>
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/of.h>
26 #include <linux/of_device.h>
27 #include <linux/pinctrl/pinctrl.h>
28 #include <linux/pinctrl/pinconf.h>
29 #include <linux/pinctrl/pinconf-generic.h>
30 #include <linux/platform_device.h>
31 #include <linux/pm_runtime.h>
32 #include <linux/rtc.h>
33 
34 /*
35  * The OMAP RTC is a year/month/day/hours/minutes/seconds BCD clock
36  * with century-range alarm matching, driven by the 32kHz clock.
37  *
38  * The main user-visible ways it differs from PC RTCs are by omitting
39  * "don't care" alarm fields and sub-second periodic IRQs, and having
40  * an autoadjust mechanism to calibrate to the true oscillator rate.
41  *
42  * Board-specific wiring options include using split power mode with
43  * RTC_OFF_NOFF used as the reset signal (so the RTC won't be reset),
44  * and wiring RTC_WAKE_INT (so the RTC alarm can wake the system from
45  * low power modes) for OMAP1 boards (OMAP-L138 has this built into
46  * the SoC). See the BOARD-SPECIFIC CUSTOMIZATION comment.
47  */
48 
49 /* RTC registers */
50 #define OMAP_RTC_SECONDS_REG		0x00
51 #define OMAP_RTC_MINUTES_REG		0x04
52 #define OMAP_RTC_HOURS_REG		0x08
53 #define OMAP_RTC_DAYS_REG		0x0C
54 #define OMAP_RTC_MONTHS_REG		0x10
55 #define OMAP_RTC_YEARS_REG		0x14
56 #define OMAP_RTC_WEEKS_REG		0x18
57 
58 #define OMAP_RTC_ALARM_SECONDS_REG	0x20
59 #define OMAP_RTC_ALARM_MINUTES_REG	0x24
60 #define OMAP_RTC_ALARM_HOURS_REG	0x28
61 #define OMAP_RTC_ALARM_DAYS_REG		0x2c
62 #define OMAP_RTC_ALARM_MONTHS_REG	0x30
63 #define OMAP_RTC_ALARM_YEARS_REG	0x34
64 
65 #define OMAP_RTC_CTRL_REG		0x40
66 #define OMAP_RTC_STATUS_REG		0x44
67 #define OMAP_RTC_INTERRUPTS_REG		0x48
68 
69 #define OMAP_RTC_COMP_LSB_REG		0x4c
70 #define OMAP_RTC_COMP_MSB_REG		0x50
71 #define OMAP_RTC_OSC_REG		0x54
72 
73 #define OMAP_RTC_KICK0_REG		0x6c
74 #define OMAP_RTC_KICK1_REG		0x70
75 
76 #define OMAP_RTC_IRQWAKEEN		0x7c
77 
78 #define OMAP_RTC_ALARM2_SECONDS_REG	0x80
79 #define OMAP_RTC_ALARM2_MINUTES_REG	0x84
80 #define OMAP_RTC_ALARM2_HOURS_REG	0x88
81 #define OMAP_RTC_ALARM2_DAYS_REG	0x8c
82 #define OMAP_RTC_ALARM2_MONTHS_REG	0x90
83 #define OMAP_RTC_ALARM2_YEARS_REG	0x94
84 
85 #define OMAP_RTC_PMIC_REG		0x98
86 
87 /* OMAP_RTC_CTRL_REG bit fields: */
88 #define OMAP_RTC_CTRL_SPLIT		BIT(7)
89 #define OMAP_RTC_CTRL_DISABLE		BIT(6)
90 #define OMAP_RTC_CTRL_SET_32_COUNTER	BIT(5)
91 #define OMAP_RTC_CTRL_TEST		BIT(4)
92 #define OMAP_RTC_CTRL_MODE_12_24	BIT(3)
93 #define OMAP_RTC_CTRL_AUTO_COMP		BIT(2)
94 #define OMAP_RTC_CTRL_ROUND_30S		BIT(1)
95 #define OMAP_RTC_CTRL_STOP		BIT(0)
96 
97 /* OMAP_RTC_STATUS_REG bit fields: */
98 #define OMAP_RTC_STATUS_POWER_UP	BIT(7)
99 #define OMAP_RTC_STATUS_ALARM2		BIT(7)
100 #define OMAP_RTC_STATUS_ALARM		BIT(6)
101 #define OMAP_RTC_STATUS_1D_EVENT	BIT(5)
102 #define OMAP_RTC_STATUS_1H_EVENT	BIT(4)
103 #define OMAP_RTC_STATUS_1M_EVENT	BIT(3)
104 #define OMAP_RTC_STATUS_1S_EVENT	BIT(2)
105 #define OMAP_RTC_STATUS_RUN		BIT(1)
106 #define OMAP_RTC_STATUS_BUSY		BIT(0)
107 
108 /* OMAP_RTC_INTERRUPTS_REG bit fields: */
109 #define OMAP_RTC_INTERRUPTS_IT_ALARM2	BIT(4)
110 #define OMAP_RTC_INTERRUPTS_IT_ALARM	BIT(3)
111 #define OMAP_RTC_INTERRUPTS_IT_TIMER	BIT(2)
112 
113 /* OMAP_RTC_OSC_REG bit fields: */
114 #define OMAP_RTC_OSC_32KCLK_EN		BIT(6)
115 #define OMAP_RTC_OSC_SEL_32KCLK_SRC	BIT(3)
116 #define OMAP_RTC_OSC_OSC32K_GZ_DISABLE	BIT(4)
117 
118 /* OMAP_RTC_IRQWAKEEN bit fields: */
119 #define OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN	BIT(1)
120 
121 /* OMAP_RTC_PMIC bit fields: */
122 #define OMAP_RTC_PMIC_POWER_EN_EN	BIT(16)
123 #define OMAP_RTC_PMIC_EXT_WKUP_EN(x)	BIT(x)
124 #define OMAP_RTC_PMIC_EXT_WKUP_POL(x)	BIT(4 + x)
125 
126 /* OMAP_RTC_KICKER values */
127 #define	KICK0_VALUE			0x83e70b13
128 #define	KICK1_VALUE			0x95a4f1e0
129 
130 struct omap_rtc;
131 
132 struct omap_rtc_device_type {
133 	bool has_32kclk_en;
134 	bool has_irqwakeen;
135 	bool has_pmic_mode;
136 	bool has_power_up_reset;
137 	void (*lock)(struct omap_rtc *rtc);
138 	void (*unlock)(struct omap_rtc *rtc);
139 };
140 
141 struct omap_rtc {
142 	struct rtc_device *rtc;
143 	void __iomem *base;
144 	struct clk *clk;
145 	int irq_alarm;
146 	int irq_timer;
147 	u8 interrupts_reg;
148 	bool is_pmic_controller;
149 	bool has_ext_clk;
150 	bool is_suspending;
151 	const struct omap_rtc_device_type *type;
152 	struct pinctrl_dev *pctldev;
153 };
154 
155 static inline u8 rtc_read(struct omap_rtc *rtc, unsigned int reg)
156 {
157 	return readb(rtc->base + reg);
158 }
159 
160 static inline u32 rtc_readl(struct omap_rtc *rtc, unsigned int reg)
161 {
162 	return readl(rtc->base + reg);
163 }
164 
165 static inline void rtc_write(struct omap_rtc *rtc, unsigned int reg, u8 val)
166 {
167 	writeb(val, rtc->base + reg);
168 }
169 
170 static inline void rtc_writel(struct omap_rtc *rtc, unsigned int reg, u32 val)
171 {
172 	writel(val, rtc->base + reg);
173 }
174 
175 static void am3352_rtc_unlock(struct omap_rtc *rtc)
176 {
177 	rtc_writel(rtc, OMAP_RTC_KICK0_REG, KICK0_VALUE);
178 	rtc_writel(rtc, OMAP_RTC_KICK1_REG, KICK1_VALUE);
179 }
180 
181 static void am3352_rtc_lock(struct omap_rtc *rtc)
182 {
183 	rtc_writel(rtc, OMAP_RTC_KICK0_REG, 0);
184 	rtc_writel(rtc, OMAP_RTC_KICK1_REG, 0);
185 }
186 
187 static void default_rtc_unlock(struct omap_rtc *rtc)
188 {
189 }
190 
191 static void default_rtc_lock(struct omap_rtc *rtc)
192 {
193 }
194 
195 /*
196  * We rely on the rtc framework to handle locking (rtc->ops_lock),
197  * so the only other requirement is that register accesses which
198  * require BUSY to be clear are made with IRQs locally disabled
199  */
200 static void rtc_wait_not_busy(struct omap_rtc *rtc)
201 {
202 	int count;
203 	u8 status;
204 
205 	/* BUSY may stay active for 1/32768 second (~30 usec) */
206 	for (count = 0; count < 50; count++) {
207 		status = rtc_read(rtc, OMAP_RTC_STATUS_REG);
208 		if (!(status & OMAP_RTC_STATUS_BUSY))
209 			break;
210 		udelay(1);
211 	}
212 	/* now we have ~15 usec to read/write various registers */
213 }
214 
215 static irqreturn_t rtc_irq(int irq, void *dev_id)
216 {
217 	struct omap_rtc	*rtc = dev_id;
218 	unsigned long events = 0;
219 	u8 irq_data;
220 
221 	irq_data = rtc_read(rtc, OMAP_RTC_STATUS_REG);
222 
223 	/* alarm irq? */
224 	if (irq_data & OMAP_RTC_STATUS_ALARM) {
225 		rtc->type->unlock(rtc);
226 		rtc_write(rtc, OMAP_RTC_STATUS_REG, OMAP_RTC_STATUS_ALARM);
227 		rtc->type->lock(rtc);
228 		events |= RTC_IRQF | RTC_AF;
229 	}
230 
231 	/* 1/sec periodic/update irq? */
232 	if (irq_data & OMAP_RTC_STATUS_1S_EVENT)
233 		events |= RTC_IRQF | RTC_UF;
234 
235 	rtc_update_irq(rtc->rtc, 1, events);
236 
237 	return IRQ_HANDLED;
238 }
239 
240 static int omap_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
241 {
242 	struct omap_rtc *rtc = dev_get_drvdata(dev);
243 	u8 reg, irqwake_reg = 0;
244 
245 	local_irq_disable();
246 	rtc_wait_not_busy(rtc);
247 	reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
248 	if (rtc->type->has_irqwakeen)
249 		irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);
250 
251 	if (enabled) {
252 		reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
253 		irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
254 	} else {
255 		reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
256 		irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
257 	}
258 	rtc_wait_not_busy(rtc);
259 	rtc->type->unlock(rtc);
260 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
261 	if (rtc->type->has_irqwakeen)
262 		rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
263 	rtc->type->lock(rtc);
264 	local_irq_enable();
265 
266 	return 0;
267 }
268 
269 /* this hardware doesn't support "don't care" alarm fields */
270 static int tm2bcd(struct rtc_time *tm)
271 {
272 	if (rtc_valid_tm(tm) != 0)
273 		return -EINVAL;
274 
275 	tm->tm_sec = bin2bcd(tm->tm_sec);
276 	tm->tm_min = bin2bcd(tm->tm_min);
277 	tm->tm_hour = bin2bcd(tm->tm_hour);
278 	tm->tm_mday = bin2bcd(tm->tm_mday);
279 
280 	tm->tm_mon = bin2bcd(tm->tm_mon + 1);
281 
282 	/* epoch == 1900 */
283 	if (tm->tm_year < 100 || tm->tm_year > 199)
284 		return -EINVAL;
285 	tm->tm_year = bin2bcd(tm->tm_year - 100);
286 
287 	return 0;
288 }
289 
290 static void bcd2tm(struct rtc_time *tm)
291 {
292 	tm->tm_sec = bcd2bin(tm->tm_sec);
293 	tm->tm_min = bcd2bin(tm->tm_min);
294 	tm->tm_hour = bcd2bin(tm->tm_hour);
295 	tm->tm_mday = bcd2bin(tm->tm_mday);
296 	tm->tm_mon = bcd2bin(tm->tm_mon) - 1;
297 	/* epoch == 1900 */
298 	tm->tm_year = bcd2bin(tm->tm_year) + 100;
299 }
300 
301 static void omap_rtc_read_time_raw(struct omap_rtc *rtc, struct rtc_time *tm)
302 {
303 	tm->tm_sec = rtc_read(rtc, OMAP_RTC_SECONDS_REG);
304 	tm->tm_min = rtc_read(rtc, OMAP_RTC_MINUTES_REG);
305 	tm->tm_hour = rtc_read(rtc, OMAP_RTC_HOURS_REG);
306 	tm->tm_mday = rtc_read(rtc, OMAP_RTC_DAYS_REG);
307 	tm->tm_mon = rtc_read(rtc, OMAP_RTC_MONTHS_REG);
308 	tm->tm_year = rtc_read(rtc, OMAP_RTC_YEARS_REG);
309 }
310 
311 static int omap_rtc_read_time(struct device *dev, struct rtc_time *tm)
312 {
313 	struct omap_rtc *rtc = dev_get_drvdata(dev);
314 
315 	/* we don't report wday/yday/isdst ... */
316 	local_irq_disable();
317 	rtc_wait_not_busy(rtc);
318 	omap_rtc_read_time_raw(rtc, tm);
319 	local_irq_enable();
320 
321 	bcd2tm(tm);
322 
323 	return 0;
324 }
325 
326 static int omap_rtc_set_time(struct device *dev, struct rtc_time *tm)
327 {
328 	struct omap_rtc *rtc = dev_get_drvdata(dev);
329 
330 	if (tm2bcd(tm) < 0)
331 		return -EINVAL;
332 
333 	local_irq_disable();
334 	rtc_wait_not_busy(rtc);
335 
336 	rtc->type->unlock(rtc);
337 	rtc_write(rtc, OMAP_RTC_YEARS_REG, tm->tm_year);
338 	rtc_write(rtc, OMAP_RTC_MONTHS_REG, tm->tm_mon);
339 	rtc_write(rtc, OMAP_RTC_DAYS_REG, tm->tm_mday);
340 	rtc_write(rtc, OMAP_RTC_HOURS_REG, tm->tm_hour);
341 	rtc_write(rtc, OMAP_RTC_MINUTES_REG, tm->tm_min);
342 	rtc_write(rtc, OMAP_RTC_SECONDS_REG, tm->tm_sec);
343 	rtc->type->lock(rtc);
344 
345 	local_irq_enable();
346 
347 	return 0;
348 }
349 
350 static int omap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
351 {
352 	struct omap_rtc *rtc = dev_get_drvdata(dev);
353 	u8 interrupts;
354 
355 	local_irq_disable();
356 	rtc_wait_not_busy(rtc);
357 
358 	alm->time.tm_sec = rtc_read(rtc, OMAP_RTC_ALARM_SECONDS_REG);
359 	alm->time.tm_min = rtc_read(rtc, OMAP_RTC_ALARM_MINUTES_REG);
360 	alm->time.tm_hour = rtc_read(rtc, OMAP_RTC_ALARM_HOURS_REG);
361 	alm->time.tm_mday = rtc_read(rtc, OMAP_RTC_ALARM_DAYS_REG);
362 	alm->time.tm_mon = rtc_read(rtc, OMAP_RTC_ALARM_MONTHS_REG);
363 	alm->time.tm_year = rtc_read(rtc, OMAP_RTC_ALARM_YEARS_REG);
364 
365 	local_irq_enable();
366 
367 	bcd2tm(&alm->time);
368 
369 	interrupts = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
370 	alm->enabled = !!(interrupts & OMAP_RTC_INTERRUPTS_IT_ALARM);
371 
372 	return 0;
373 }
374 
375 static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
376 {
377 	struct omap_rtc *rtc = dev_get_drvdata(dev);
378 	u8 reg, irqwake_reg = 0;
379 
380 	if (tm2bcd(&alm->time) < 0)
381 		return -EINVAL;
382 
383 	local_irq_disable();
384 	rtc_wait_not_busy(rtc);
385 
386 	rtc->type->unlock(rtc);
387 	rtc_write(rtc, OMAP_RTC_ALARM_YEARS_REG, alm->time.tm_year);
388 	rtc_write(rtc, OMAP_RTC_ALARM_MONTHS_REG, alm->time.tm_mon);
389 	rtc_write(rtc, OMAP_RTC_ALARM_DAYS_REG, alm->time.tm_mday);
390 	rtc_write(rtc, OMAP_RTC_ALARM_HOURS_REG, alm->time.tm_hour);
391 	rtc_write(rtc, OMAP_RTC_ALARM_MINUTES_REG, alm->time.tm_min);
392 	rtc_write(rtc, OMAP_RTC_ALARM_SECONDS_REG, alm->time.tm_sec);
393 
394 	reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
395 	if (rtc->type->has_irqwakeen)
396 		irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);
397 
398 	if (alm->enabled) {
399 		reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
400 		irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
401 	} else {
402 		reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
403 		irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
404 	}
405 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
406 	if (rtc->type->has_irqwakeen)
407 		rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
408 	rtc->type->lock(rtc);
409 
410 	local_irq_enable();
411 
412 	return 0;
413 }
414 
415 static struct omap_rtc *omap_rtc_power_off_rtc;
416 
417 /*
418  * omap_rtc_poweroff: RTC-controlled power off
419  *
420  * The RTC can be used to control an external PMIC via the pmic_power_en pin,
421  * which can be configured to transition to OFF on ALARM2 events.
422  *
423  * Notes:
424  * The two-second alarm offset is the shortest offset possible as the alarm
425  * registers must be set before the next timer update and the offset
426  * calculation is too heavy for everything to be done within a single access
427  * period (~15 us).
428  *
429  * Called with local interrupts disabled.
430  */
431 static void omap_rtc_power_off(void)
432 {
433 	struct omap_rtc *rtc = omap_rtc_power_off_rtc;
434 	struct rtc_time tm;
435 	unsigned long now;
436 	u32 val;
437 
438 	rtc->type->unlock(rtc);
439 	/* enable pmic_power_en control */
440 	val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
441 	rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
442 
443 	/* set alarm two seconds from now */
444 	omap_rtc_read_time_raw(rtc, &tm);
445 	bcd2tm(&tm);
446 	rtc_tm_to_time(&tm, &now);
447 	rtc_time_to_tm(now + 2, &tm);
448 
449 	if (tm2bcd(&tm) < 0) {
450 		dev_err(&rtc->rtc->dev, "power off failed\n");
451 		return;
452 	}
453 
454 	rtc_wait_not_busy(rtc);
455 
456 	rtc_write(rtc, OMAP_RTC_ALARM2_SECONDS_REG, tm.tm_sec);
457 	rtc_write(rtc, OMAP_RTC_ALARM2_MINUTES_REG, tm.tm_min);
458 	rtc_write(rtc, OMAP_RTC_ALARM2_HOURS_REG, tm.tm_hour);
459 	rtc_write(rtc, OMAP_RTC_ALARM2_DAYS_REG, tm.tm_mday);
460 	rtc_write(rtc, OMAP_RTC_ALARM2_MONTHS_REG, tm.tm_mon);
461 	rtc_write(rtc, OMAP_RTC_ALARM2_YEARS_REG, tm.tm_year);
462 
463 	/*
464 	 * enable ALARM2 interrupt
465 	 *
466 	 * NOTE: this fails on AM3352 if rtc_write (writeb) is used
467 	 */
468 	val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
469 	rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
470 			val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
471 	rtc->type->lock(rtc);
472 
473 	/*
474 	 * Wait for alarm to trigger (within two seconds) and external PMIC to
475 	 * power off the system. Add a 500 ms margin for external latencies
476 	 * (e.g. debounce circuits).
477 	 */
478 	mdelay(2500);
479 }
480 
481 static const struct rtc_class_ops omap_rtc_ops = {
482 	.read_time	= omap_rtc_read_time,
483 	.set_time	= omap_rtc_set_time,
484 	.read_alarm	= omap_rtc_read_alarm,
485 	.set_alarm	= omap_rtc_set_alarm,
486 	.alarm_irq_enable = omap_rtc_alarm_irq_enable,
487 };
488 
489 static const struct omap_rtc_device_type omap_rtc_default_type = {
490 	.has_power_up_reset = true,
491 	.lock		= default_rtc_lock,
492 	.unlock		= default_rtc_unlock,
493 };
494 
495 static const struct omap_rtc_device_type omap_rtc_am3352_type = {
496 	.has_32kclk_en	= true,
497 	.has_irqwakeen	= true,
498 	.has_pmic_mode	= true,
499 	.lock		= am3352_rtc_lock,
500 	.unlock		= am3352_rtc_unlock,
501 };
502 
503 static const struct omap_rtc_device_type omap_rtc_da830_type = {
504 	.lock		= am3352_rtc_lock,
505 	.unlock		= am3352_rtc_unlock,
506 };
507 
508 static const struct platform_device_id omap_rtc_id_table[] = {
509 	{
510 		.name	= "omap_rtc",
511 		.driver_data = (kernel_ulong_t)&omap_rtc_default_type,
512 	}, {
513 		.name	= "am3352-rtc",
514 		.driver_data = (kernel_ulong_t)&omap_rtc_am3352_type,
515 	}, {
516 		.name	= "da830-rtc",
517 		.driver_data = (kernel_ulong_t)&omap_rtc_da830_type,
518 	}, {
519 		/* sentinel */
520 	}
521 };
522 MODULE_DEVICE_TABLE(platform, omap_rtc_id_table);
523 
524 static const struct of_device_id omap_rtc_of_match[] = {
525 	{
526 		.compatible	= "ti,am3352-rtc",
527 		.data		= &omap_rtc_am3352_type,
528 	}, {
529 		.compatible	= "ti,da830-rtc",
530 		.data		= &omap_rtc_da830_type,
531 	}, {
532 		/* sentinel */
533 	}
534 };
535 MODULE_DEVICE_TABLE(of, omap_rtc_of_match);
536 
537 static const struct pinctrl_pin_desc rtc_pins_desc[] = {
538 	PINCTRL_PIN(0, "ext_wakeup0"),
539 	PINCTRL_PIN(1, "ext_wakeup1"),
540 	PINCTRL_PIN(2, "ext_wakeup2"),
541 	PINCTRL_PIN(3, "ext_wakeup3"),
542 };
543 
544 static int rtc_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
545 {
546 	return 0;
547 }
548 
549 static const char *rtc_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
550 					unsigned int group)
551 {
552 	return NULL;
553 }
554 
555 static const struct pinctrl_ops rtc_pinctrl_ops = {
556 	.get_groups_count = rtc_pinctrl_get_groups_count,
557 	.get_group_name = rtc_pinctrl_get_group_name,
558 	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
559 	.dt_free_map = pinconf_generic_dt_free_map,
560 };
561 
562 enum rtc_pin_config_param {
563 	PIN_CONFIG_ACTIVE_HIGH = PIN_CONFIG_END + 1,
564 };
565 
566 static const struct pinconf_generic_params rtc_params[] = {
567 	{"ti,active-high", PIN_CONFIG_ACTIVE_HIGH, 0},
568 };
569 
570 #ifdef CONFIG_DEBUG_FS
571 static const struct pin_config_item rtc_conf_items[ARRAY_SIZE(rtc_params)] = {
572 	PCONFDUMP(PIN_CONFIG_ACTIVE_HIGH, "input active high", NULL, false),
573 };
574 #endif
575 
576 static int rtc_pinconf_get(struct pinctrl_dev *pctldev,
577 			unsigned int pin, unsigned long *config)
578 {
579 	struct omap_rtc *rtc = pinctrl_dev_get_drvdata(pctldev);
580 	unsigned int param = pinconf_to_config_param(*config);
581 	u32 val;
582 	u16 arg = 0;
583 
584 	rtc->type->unlock(rtc);
585 	val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
586 	rtc->type->lock(rtc);
587 
588 	switch (param) {
589 	case PIN_CONFIG_INPUT_ENABLE:
590 		if (!(val & OMAP_RTC_PMIC_EXT_WKUP_EN(pin)))
591 			return -EINVAL;
592 		break;
593 	case PIN_CONFIG_ACTIVE_HIGH:
594 		if (val & OMAP_RTC_PMIC_EXT_WKUP_POL(pin))
595 			return -EINVAL;
596 		break;
597 	default:
598 		return -ENOTSUPP;
599 	};
600 
601 	*config = pinconf_to_config_packed(param, arg);
602 
603 	return 0;
604 }
605 
606 static int rtc_pinconf_set(struct pinctrl_dev *pctldev,
607 			unsigned int pin, unsigned long *configs,
608 			unsigned int num_configs)
609 {
610 	struct omap_rtc *rtc = pinctrl_dev_get_drvdata(pctldev);
611 	u32 val;
612 	unsigned int param;
613 	u16 param_val;
614 	int i;
615 
616 	rtc->type->unlock(rtc);
617 	val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
618 	rtc->type->lock(rtc);
619 
620 	/* active low by default */
621 	val |= OMAP_RTC_PMIC_EXT_WKUP_POL(pin);
622 
623 	for (i = 0; i < num_configs; i++) {
624 		param = pinconf_to_config_param(configs[i]);
625 		param_val = pinconf_to_config_argument(configs[i]);
626 
627 		switch (param) {
628 		case PIN_CONFIG_INPUT_ENABLE:
629 			if (param_val)
630 				val |= OMAP_RTC_PMIC_EXT_WKUP_EN(pin);
631 			else
632 				val &= ~OMAP_RTC_PMIC_EXT_WKUP_EN(pin);
633 			break;
634 		case PIN_CONFIG_ACTIVE_HIGH:
635 			val &= ~OMAP_RTC_PMIC_EXT_WKUP_POL(pin);
636 			break;
637 		default:
638 			dev_err(&rtc->rtc->dev, "Property %u not supported\n",
639 				param);
640 			return -ENOTSUPP;
641 		}
642 	}
643 
644 	rtc->type->unlock(rtc);
645 	rtc_writel(rtc, OMAP_RTC_PMIC_REG, val);
646 	rtc->type->lock(rtc);
647 
648 	return 0;
649 }
650 
651 static const struct pinconf_ops rtc_pinconf_ops = {
652 	.is_generic = true,
653 	.pin_config_get = rtc_pinconf_get,
654 	.pin_config_set = rtc_pinconf_set,
655 };
656 
657 static struct pinctrl_desc rtc_pinctrl_desc = {
658 	.pins = rtc_pins_desc,
659 	.npins = ARRAY_SIZE(rtc_pins_desc),
660 	.pctlops = &rtc_pinctrl_ops,
661 	.confops = &rtc_pinconf_ops,
662 	.custom_params = rtc_params,
663 	.num_custom_params = ARRAY_SIZE(rtc_params),
664 #ifdef CONFIG_DEBUG_FS
665 	.custom_conf_items = rtc_conf_items,
666 #endif
667 	.owner = THIS_MODULE,
668 };
669 
670 static int omap_rtc_probe(struct platform_device *pdev)
671 {
672 	struct omap_rtc	*rtc;
673 	struct resource	*res;
674 	u8 reg, mask, new_ctrl;
675 	const struct platform_device_id *id_entry;
676 	const struct of_device_id *of_id;
677 	int ret;
678 
679 	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
680 	if (!rtc)
681 		return -ENOMEM;
682 
683 	of_id = of_match_device(omap_rtc_of_match, &pdev->dev);
684 	if (of_id) {
685 		rtc->type = of_id->data;
686 		rtc->is_pmic_controller = rtc->type->has_pmic_mode &&
687 				of_property_read_bool(pdev->dev.of_node,
688 						"system-power-controller");
689 	} else {
690 		id_entry = platform_get_device_id(pdev);
691 		rtc->type = (void *)id_entry->driver_data;
692 	}
693 
694 	rtc->irq_timer = platform_get_irq(pdev, 0);
695 	if (rtc->irq_timer <= 0)
696 		return -ENOENT;
697 
698 	rtc->irq_alarm = platform_get_irq(pdev, 1);
699 	if (rtc->irq_alarm <= 0)
700 		return -ENOENT;
701 
702 	rtc->clk = devm_clk_get(&pdev->dev, "ext-clk");
703 	if (!IS_ERR(rtc->clk))
704 		rtc->has_ext_clk = true;
705 	else
706 		rtc->clk = devm_clk_get(&pdev->dev, "int-clk");
707 
708 	if (!IS_ERR(rtc->clk))
709 		clk_prepare_enable(rtc->clk);
710 
711 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
712 	rtc->base = devm_ioremap_resource(&pdev->dev, res);
713 	if (IS_ERR(rtc->base))
714 		return PTR_ERR(rtc->base);
715 
716 	platform_set_drvdata(pdev, rtc);
717 
718 	/* Enable the clock/module so that we can access the registers */
719 	pm_runtime_enable(&pdev->dev);
720 	pm_runtime_get_sync(&pdev->dev);
721 
722 	rtc->type->unlock(rtc);
723 
724 	/*
725 	 * disable interrupts
726 	 *
727 	 * NOTE: ALARM2 is not cleared on AM3352 if rtc_write (writeb) is used
728 	 */
729 	rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
730 
731 	/* enable RTC functional clock */
732 	if (rtc->type->has_32kclk_en) {
733 		reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
734 		rtc_writel(rtc, OMAP_RTC_OSC_REG,
735 				reg | OMAP_RTC_OSC_32KCLK_EN);
736 	}
737 
738 	/* clear old status */
739 	reg = rtc_read(rtc, OMAP_RTC_STATUS_REG);
740 
741 	mask = OMAP_RTC_STATUS_ALARM;
742 
743 	if (rtc->type->has_pmic_mode)
744 		mask |= OMAP_RTC_STATUS_ALARM2;
745 
746 	if (rtc->type->has_power_up_reset) {
747 		mask |= OMAP_RTC_STATUS_POWER_UP;
748 		if (reg & OMAP_RTC_STATUS_POWER_UP)
749 			dev_info(&pdev->dev, "RTC power up reset detected\n");
750 	}
751 
752 	if (reg & mask)
753 		rtc_write(rtc, OMAP_RTC_STATUS_REG, reg & mask);
754 
755 	/* On boards with split power, RTC_ON_NOFF won't reset the RTC */
756 	reg = rtc_read(rtc, OMAP_RTC_CTRL_REG);
757 	if (reg & OMAP_RTC_CTRL_STOP)
758 		dev_info(&pdev->dev, "already running\n");
759 
760 	/* force to 24 hour mode */
761 	new_ctrl = reg & (OMAP_RTC_CTRL_SPLIT | OMAP_RTC_CTRL_AUTO_COMP);
762 	new_ctrl |= OMAP_RTC_CTRL_STOP;
763 
764 	/*
765 	 * BOARD-SPECIFIC CUSTOMIZATION CAN GO HERE:
766 	 *
767 	 *  - Device wake-up capability setting should come through chip
768 	 *    init logic. OMAP1 boards should initialize the "wakeup capable"
769 	 *    flag in the platform device if the board is wired right for
770 	 *    being woken up by RTC alarm. For OMAP-L138, this capability
771 	 *    is built into the SoC by the "Deep Sleep" capability.
772 	 *
773 	 *  - Boards wired so RTC_ON_nOFF is used as the reset signal,
774 	 *    rather than nPWRON_RESET, should forcibly enable split
775 	 *    power mode.  (Some chip errata report that RTC_CTRL_SPLIT
776 	 *    is write-only, and always reads as zero...)
777 	 */
778 
779 	if (new_ctrl & OMAP_RTC_CTRL_SPLIT)
780 		dev_info(&pdev->dev, "split power mode\n");
781 
782 	if (reg != new_ctrl)
783 		rtc_write(rtc, OMAP_RTC_CTRL_REG, new_ctrl);
784 
785 	/*
786 	 * If we have the external clock then switch to it so we can keep
787 	 * ticking across suspend.
788 	 */
789 	if (rtc->has_ext_clk) {
790 		reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
791 		reg &= ~OMAP_RTC_OSC_OSC32K_GZ_DISABLE;
792 		reg |= OMAP_RTC_OSC_32KCLK_EN | OMAP_RTC_OSC_SEL_32KCLK_SRC;
793 		rtc_writel(rtc, OMAP_RTC_OSC_REG, reg);
794 	}
795 
796 	rtc->type->lock(rtc);
797 
798 	device_init_wakeup(&pdev->dev, true);
799 
800 	rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
801 			&omap_rtc_ops, THIS_MODULE);
802 	if (IS_ERR(rtc->rtc)) {
803 		ret = PTR_ERR(rtc->rtc);
804 		goto err;
805 	}
806 
807 	/* handle periodic and alarm irqs */
808 	ret = devm_request_irq(&pdev->dev, rtc->irq_timer, rtc_irq, 0,
809 			dev_name(&rtc->rtc->dev), rtc);
810 	if (ret)
811 		goto err;
812 
813 	if (rtc->irq_timer != rtc->irq_alarm) {
814 		ret = devm_request_irq(&pdev->dev, rtc->irq_alarm, rtc_irq, 0,
815 				dev_name(&rtc->rtc->dev), rtc);
816 		if (ret)
817 			goto err;
818 	}
819 
820 	if (rtc->is_pmic_controller) {
821 		if (!pm_power_off) {
822 			omap_rtc_power_off_rtc = rtc;
823 			pm_power_off = omap_rtc_power_off;
824 		}
825 	}
826 
827 	/* Support ext_wakeup pinconf */
828 	rtc_pinctrl_desc.name = dev_name(&pdev->dev);
829 
830 	rtc->pctldev = pinctrl_register(&rtc_pinctrl_desc, &pdev->dev, rtc);
831 	if (IS_ERR(rtc->pctldev)) {
832 		dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
833 		return PTR_ERR(rtc->pctldev);
834 	}
835 
836 	return 0;
837 
838 err:
839 	device_init_wakeup(&pdev->dev, false);
840 	rtc->type->lock(rtc);
841 	pm_runtime_put_sync(&pdev->dev);
842 	pm_runtime_disable(&pdev->dev);
843 
844 	return ret;
845 }
846 
847 static int __exit omap_rtc_remove(struct platform_device *pdev)
848 {
849 	struct omap_rtc *rtc = platform_get_drvdata(pdev);
850 	u8 reg;
851 
852 	if (pm_power_off == omap_rtc_power_off &&
853 			omap_rtc_power_off_rtc == rtc) {
854 		pm_power_off = NULL;
855 		omap_rtc_power_off_rtc = NULL;
856 	}
857 
858 	device_init_wakeup(&pdev->dev, 0);
859 
860 	if (!IS_ERR(rtc->clk))
861 		clk_disable_unprepare(rtc->clk);
862 
863 	rtc->type->unlock(rtc);
864 	/* leave rtc running, but disable irqs */
865 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
866 
867 	if (rtc->has_ext_clk) {
868 		reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
869 		reg &= ~OMAP_RTC_OSC_SEL_32KCLK_SRC;
870 		rtc_write(rtc, OMAP_RTC_OSC_REG, reg);
871 	}
872 
873 	rtc->type->lock(rtc);
874 
875 	/* Disable the clock/module */
876 	pm_runtime_put_sync(&pdev->dev);
877 	pm_runtime_disable(&pdev->dev);
878 
879 	/* Remove ext_wakeup pinconf */
880 	pinctrl_unregister(rtc->pctldev);
881 
882 	return 0;
883 }
884 
885 #ifdef CONFIG_PM_SLEEP
886 static int omap_rtc_suspend(struct device *dev)
887 {
888 	struct omap_rtc *rtc = dev_get_drvdata(dev);
889 
890 	rtc->interrupts_reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
891 
892 	rtc->type->unlock(rtc);
893 	/*
894 	 * FIXME: the RTC alarm is not currently acting as a wakeup event
895 	 * source on some platforms, and in fact this enable() call is just
896 	 * saving a flag that's never used...
897 	 */
898 	if (device_may_wakeup(dev))
899 		enable_irq_wake(rtc->irq_alarm);
900 	else
901 		rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
902 	rtc->type->lock(rtc);
903 
904 	rtc->is_suspending = true;
905 
906 	return 0;
907 }
908 
909 static int omap_rtc_resume(struct device *dev)
910 {
911 	struct omap_rtc *rtc = dev_get_drvdata(dev);
912 
913 	rtc->type->unlock(rtc);
914 	if (device_may_wakeup(dev))
915 		disable_irq_wake(rtc->irq_alarm);
916 	else
917 		rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, rtc->interrupts_reg);
918 	rtc->type->lock(rtc);
919 
920 	rtc->is_suspending = false;
921 
922 	return 0;
923 }
924 #endif
925 
926 #ifdef CONFIG_PM
927 static int omap_rtc_runtime_suspend(struct device *dev)
928 {
929 	struct omap_rtc *rtc = dev_get_drvdata(dev);
930 
931 	if (rtc->is_suspending && !rtc->has_ext_clk)
932 		return -EBUSY;
933 
934 	return 0;
935 }
936 
937 static int omap_rtc_runtime_resume(struct device *dev)
938 {
939 	return 0;
940 }
941 #endif
942 
943 static const struct dev_pm_ops omap_rtc_pm_ops = {
944 	SET_SYSTEM_SLEEP_PM_OPS(omap_rtc_suspend, omap_rtc_resume)
945 	SET_RUNTIME_PM_OPS(omap_rtc_runtime_suspend,
946 			   omap_rtc_runtime_resume, NULL)
947 };
948 
949 static void omap_rtc_shutdown(struct platform_device *pdev)
950 {
951 	struct omap_rtc *rtc = platform_get_drvdata(pdev);
952 	u8 mask;
953 
954 	/*
955 	 * Keep the ALARM interrupt enabled to allow the system to power up on
956 	 * alarm events.
957 	 */
958 	rtc->type->unlock(rtc);
959 	mask = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
960 	mask &= OMAP_RTC_INTERRUPTS_IT_ALARM;
961 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, mask);
962 	rtc->type->lock(rtc);
963 }
964 
965 static struct platform_driver omap_rtc_driver = {
966 	.probe		= omap_rtc_probe,
967 	.remove		= __exit_p(omap_rtc_remove),
968 	.shutdown	= omap_rtc_shutdown,
969 	.driver		= {
970 		.name	= "omap_rtc",
971 		.pm	= &omap_rtc_pm_ops,
972 		.of_match_table = omap_rtc_of_match,
973 	},
974 	.id_table	= omap_rtc_id_table,
975 };
976 
977 module_platform_driver(omap_rtc_driver);
978 
979 MODULE_ALIAS("platform:omap_rtc");
980 MODULE_AUTHOR("George G. Davis (and others)");
981 MODULE_LICENSE("GPL");
982