xref: /openbmc/linux/drivers/rtc/rtc-omap.c (revision d003d772)
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_SCRATCH0_REG		0x60
74 #define OMAP_RTC_SCRATCH1_REG		0x64
75 #define OMAP_RTC_SCRATCH2_REG		0x68
76 
77 #define OMAP_RTC_KICK0_REG		0x6c
78 #define OMAP_RTC_KICK1_REG		0x70
79 
80 #define OMAP_RTC_IRQWAKEEN		0x7c
81 
82 #define OMAP_RTC_ALARM2_SECONDS_REG	0x80
83 #define OMAP_RTC_ALARM2_MINUTES_REG	0x84
84 #define OMAP_RTC_ALARM2_HOURS_REG	0x88
85 #define OMAP_RTC_ALARM2_DAYS_REG	0x8c
86 #define OMAP_RTC_ALARM2_MONTHS_REG	0x90
87 #define OMAP_RTC_ALARM2_YEARS_REG	0x94
88 
89 #define OMAP_RTC_PMIC_REG		0x98
90 
91 /* OMAP_RTC_CTRL_REG bit fields: */
92 #define OMAP_RTC_CTRL_SPLIT		BIT(7)
93 #define OMAP_RTC_CTRL_DISABLE		BIT(6)
94 #define OMAP_RTC_CTRL_SET_32_COUNTER	BIT(5)
95 #define OMAP_RTC_CTRL_TEST		BIT(4)
96 #define OMAP_RTC_CTRL_MODE_12_24	BIT(3)
97 #define OMAP_RTC_CTRL_AUTO_COMP		BIT(2)
98 #define OMAP_RTC_CTRL_ROUND_30S		BIT(1)
99 #define OMAP_RTC_CTRL_STOP		BIT(0)
100 
101 /* OMAP_RTC_STATUS_REG bit fields: */
102 #define OMAP_RTC_STATUS_POWER_UP	BIT(7)
103 #define OMAP_RTC_STATUS_ALARM2		BIT(7)
104 #define OMAP_RTC_STATUS_ALARM		BIT(6)
105 #define OMAP_RTC_STATUS_1D_EVENT	BIT(5)
106 #define OMAP_RTC_STATUS_1H_EVENT	BIT(4)
107 #define OMAP_RTC_STATUS_1M_EVENT	BIT(3)
108 #define OMAP_RTC_STATUS_1S_EVENT	BIT(2)
109 #define OMAP_RTC_STATUS_RUN		BIT(1)
110 #define OMAP_RTC_STATUS_BUSY		BIT(0)
111 
112 /* OMAP_RTC_INTERRUPTS_REG bit fields: */
113 #define OMAP_RTC_INTERRUPTS_IT_ALARM2	BIT(4)
114 #define OMAP_RTC_INTERRUPTS_IT_ALARM	BIT(3)
115 #define OMAP_RTC_INTERRUPTS_IT_TIMER	BIT(2)
116 
117 /* OMAP_RTC_OSC_REG bit fields: */
118 #define OMAP_RTC_OSC_32KCLK_EN		BIT(6)
119 #define OMAP_RTC_OSC_SEL_32KCLK_SRC	BIT(3)
120 #define OMAP_RTC_OSC_OSC32K_GZ_DISABLE	BIT(4)
121 
122 /* OMAP_RTC_IRQWAKEEN bit fields: */
123 #define OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN	BIT(1)
124 
125 /* OMAP_RTC_PMIC bit fields: */
126 #define OMAP_RTC_PMIC_POWER_EN_EN	BIT(16)
127 #define OMAP_RTC_PMIC_EXT_WKUP_EN(x)	BIT(x)
128 #define OMAP_RTC_PMIC_EXT_WKUP_POL(x)	BIT(4 + x)
129 
130 /* OMAP_RTC_KICKER values */
131 #define	KICK0_VALUE			0x83e70b13
132 #define	KICK1_VALUE			0x95a4f1e0
133 
134 struct omap_rtc;
135 
136 struct omap_rtc_device_type {
137 	bool has_32kclk_en;
138 	bool has_irqwakeen;
139 	bool has_pmic_mode;
140 	bool has_power_up_reset;
141 	void (*lock)(struct omap_rtc *rtc);
142 	void (*unlock)(struct omap_rtc *rtc);
143 };
144 
145 struct omap_rtc {
146 	struct rtc_device *rtc;
147 	void __iomem *base;
148 	struct clk *clk;
149 	int irq_alarm;
150 	int irq_timer;
151 	u8 interrupts_reg;
152 	bool is_pmic_controller;
153 	bool has_ext_clk;
154 	bool is_suspending;
155 	const struct omap_rtc_device_type *type;
156 	struct pinctrl_dev *pctldev;
157 };
158 
159 static inline u8 rtc_read(struct omap_rtc *rtc, unsigned int reg)
160 {
161 	return readb(rtc->base + reg);
162 }
163 
164 static inline u32 rtc_readl(struct omap_rtc *rtc, unsigned int reg)
165 {
166 	return readl(rtc->base + reg);
167 }
168 
169 static inline void rtc_write(struct omap_rtc *rtc, unsigned int reg, u8 val)
170 {
171 	writeb(val, rtc->base + reg);
172 }
173 
174 static inline void rtc_writel(struct omap_rtc *rtc, unsigned int reg, u32 val)
175 {
176 	writel(val, rtc->base + reg);
177 }
178 
179 static void am3352_rtc_unlock(struct omap_rtc *rtc)
180 {
181 	rtc_writel(rtc, OMAP_RTC_KICK0_REG, KICK0_VALUE);
182 	rtc_writel(rtc, OMAP_RTC_KICK1_REG, KICK1_VALUE);
183 }
184 
185 static void am3352_rtc_lock(struct omap_rtc *rtc)
186 {
187 	rtc_writel(rtc, OMAP_RTC_KICK0_REG, 0);
188 	rtc_writel(rtc, OMAP_RTC_KICK1_REG, 0);
189 }
190 
191 static void default_rtc_unlock(struct omap_rtc *rtc)
192 {
193 }
194 
195 static void default_rtc_lock(struct omap_rtc *rtc)
196 {
197 }
198 
199 /*
200  * We rely on the rtc framework to handle locking (rtc->ops_lock),
201  * so the only other requirement is that register accesses which
202  * require BUSY to be clear are made with IRQs locally disabled
203  */
204 static void rtc_wait_not_busy(struct omap_rtc *rtc)
205 {
206 	int count;
207 	u8 status;
208 
209 	/* BUSY may stay active for 1/32768 second (~30 usec) */
210 	for (count = 0; count < 50; count++) {
211 		status = rtc_read(rtc, OMAP_RTC_STATUS_REG);
212 		if (!(status & OMAP_RTC_STATUS_BUSY))
213 			break;
214 		udelay(1);
215 	}
216 	/* now we have ~15 usec to read/write various registers */
217 }
218 
219 static irqreturn_t rtc_irq(int irq, void *dev_id)
220 {
221 	struct omap_rtc	*rtc = dev_id;
222 	unsigned long events = 0;
223 	u8 irq_data;
224 
225 	irq_data = rtc_read(rtc, OMAP_RTC_STATUS_REG);
226 
227 	/* alarm irq? */
228 	if (irq_data & OMAP_RTC_STATUS_ALARM) {
229 		rtc->type->unlock(rtc);
230 		rtc_write(rtc, OMAP_RTC_STATUS_REG, OMAP_RTC_STATUS_ALARM);
231 		rtc->type->lock(rtc);
232 		events |= RTC_IRQF | RTC_AF;
233 	}
234 
235 	/* 1/sec periodic/update irq? */
236 	if (irq_data & OMAP_RTC_STATUS_1S_EVENT)
237 		events |= RTC_IRQF | RTC_UF;
238 
239 	rtc_update_irq(rtc->rtc, 1, events);
240 
241 	return IRQ_HANDLED;
242 }
243 
244 static int omap_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
245 {
246 	struct omap_rtc *rtc = dev_get_drvdata(dev);
247 	u8 reg, irqwake_reg = 0;
248 
249 	local_irq_disable();
250 	rtc_wait_not_busy(rtc);
251 	reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
252 	if (rtc->type->has_irqwakeen)
253 		irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);
254 
255 	if (enabled) {
256 		reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
257 		irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
258 	} else {
259 		reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
260 		irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
261 	}
262 	rtc_wait_not_busy(rtc);
263 	rtc->type->unlock(rtc);
264 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
265 	if (rtc->type->has_irqwakeen)
266 		rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
267 	rtc->type->lock(rtc);
268 	local_irq_enable();
269 
270 	return 0;
271 }
272 
273 /* this hardware doesn't support "don't care" alarm fields */
274 static int tm2bcd(struct rtc_time *tm)
275 {
276 	tm->tm_sec = bin2bcd(tm->tm_sec);
277 	tm->tm_min = bin2bcd(tm->tm_min);
278 	tm->tm_hour = bin2bcd(tm->tm_hour);
279 	tm->tm_mday = bin2bcd(tm->tm_mday);
280 
281 	tm->tm_mon = bin2bcd(tm->tm_mon + 1);
282 
283 	/* epoch == 1900 */
284 	if (tm->tm_year < 100 || tm->tm_year > 199)
285 		return -EINVAL;
286 	tm->tm_year = bin2bcd(tm->tm_year - 100);
287 
288 	return 0;
289 }
290 
291 static void bcd2tm(struct rtc_time *tm)
292 {
293 	tm->tm_sec = bcd2bin(tm->tm_sec);
294 	tm->tm_min = bcd2bin(tm->tm_min);
295 	tm->tm_hour = bcd2bin(tm->tm_hour);
296 	tm->tm_mday = bcd2bin(tm->tm_mday);
297 	tm->tm_mon = bcd2bin(tm->tm_mon) - 1;
298 	/* epoch == 1900 */
299 	tm->tm_year = bcd2bin(tm->tm_year) + 100;
300 }
301 
302 static void omap_rtc_read_time_raw(struct omap_rtc *rtc, struct rtc_time *tm)
303 {
304 	tm->tm_sec = rtc_read(rtc, OMAP_RTC_SECONDS_REG);
305 	tm->tm_min = rtc_read(rtc, OMAP_RTC_MINUTES_REG);
306 	tm->tm_hour = rtc_read(rtc, OMAP_RTC_HOURS_REG);
307 	tm->tm_mday = rtc_read(rtc, OMAP_RTC_DAYS_REG);
308 	tm->tm_mon = rtc_read(rtc, OMAP_RTC_MONTHS_REG);
309 	tm->tm_year = rtc_read(rtc, OMAP_RTC_YEARS_REG);
310 }
311 
312 static int omap_rtc_read_time(struct device *dev, struct rtc_time *tm)
313 {
314 	struct omap_rtc *rtc = dev_get_drvdata(dev);
315 
316 	/* we don't report wday/yday/isdst ... */
317 	local_irq_disable();
318 	rtc_wait_not_busy(rtc);
319 	omap_rtc_read_time_raw(rtc, tm);
320 	local_irq_enable();
321 
322 	bcd2tm(tm);
323 
324 	return 0;
325 }
326 
327 static int omap_rtc_set_time(struct device *dev, struct rtc_time *tm)
328 {
329 	struct omap_rtc *rtc = dev_get_drvdata(dev);
330 
331 	if (tm2bcd(tm) < 0)
332 		return -EINVAL;
333 
334 	local_irq_disable();
335 	rtc_wait_not_busy(rtc);
336 
337 	rtc->type->unlock(rtc);
338 	rtc_write(rtc, OMAP_RTC_YEARS_REG, tm->tm_year);
339 	rtc_write(rtc, OMAP_RTC_MONTHS_REG, tm->tm_mon);
340 	rtc_write(rtc, OMAP_RTC_DAYS_REG, tm->tm_mday);
341 	rtc_write(rtc, OMAP_RTC_HOURS_REG, tm->tm_hour);
342 	rtc_write(rtc, OMAP_RTC_MINUTES_REG, tm->tm_min);
343 	rtc_write(rtc, OMAP_RTC_SECONDS_REG, tm->tm_sec);
344 	rtc->type->lock(rtc);
345 
346 	local_irq_enable();
347 
348 	return 0;
349 }
350 
351 static int omap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
352 {
353 	struct omap_rtc *rtc = dev_get_drvdata(dev);
354 	u8 interrupts;
355 
356 	local_irq_disable();
357 	rtc_wait_not_busy(rtc);
358 
359 	alm->time.tm_sec = rtc_read(rtc, OMAP_RTC_ALARM_SECONDS_REG);
360 	alm->time.tm_min = rtc_read(rtc, OMAP_RTC_ALARM_MINUTES_REG);
361 	alm->time.tm_hour = rtc_read(rtc, OMAP_RTC_ALARM_HOURS_REG);
362 	alm->time.tm_mday = rtc_read(rtc, OMAP_RTC_ALARM_DAYS_REG);
363 	alm->time.tm_mon = rtc_read(rtc, OMAP_RTC_ALARM_MONTHS_REG);
364 	alm->time.tm_year = rtc_read(rtc, OMAP_RTC_ALARM_YEARS_REG);
365 
366 	local_irq_enable();
367 
368 	bcd2tm(&alm->time);
369 
370 	interrupts = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
371 	alm->enabled = !!(interrupts & OMAP_RTC_INTERRUPTS_IT_ALARM);
372 
373 	return 0;
374 }
375 
376 static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
377 {
378 	struct omap_rtc *rtc = dev_get_drvdata(dev);
379 	u8 reg, irqwake_reg = 0;
380 
381 	if (tm2bcd(&alm->time) < 0)
382 		return -EINVAL;
383 
384 	local_irq_disable();
385 	rtc_wait_not_busy(rtc);
386 
387 	rtc->type->unlock(rtc);
388 	rtc_write(rtc, OMAP_RTC_ALARM_YEARS_REG, alm->time.tm_year);
389 	rtc_write(rtc, OMAP_RTC_ALARM_MONTHS_REG, alm->time.tm_mon);
390 	rtc_write(rtc, OMAP_RTC_ALARM_DAYS_REG, alm->time.tm_mday);
391 	rtc_write(rtc, OMAP_RTC_ALARM_HOURS_REG, alm->time.tm_hour);
392 	rtc_write(rtc, OMAP_RTC_ALARM_MINUTES_REG, alm->time.tm_min);
393 	rtc_write(rtc, OMAP_RTC_ALARM_SECONDS_REG, alm->time.tm_sec);
394 
395 	reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
396 	if (rtc->type->has_irqwakeen)
397 		irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);
398 
399 	if (alm->enabled) {
400 		reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
401 		irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
402 	} else {
403 		reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
404 		irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
405 	}
406 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
407 	if (rtc->type->has_irqwakeen)
408 		rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
409 	rtc->type->lock(rtc);
410 
411 	local_irq_enable();
412 
413 	return 0;
414 }
415 
416 static struct omap_rtc *omap_rtc_power_off_rtc;
417 
418 /*
419  * omap_rtc_poweroff: RTC-controlled power off
420  *
421  * The RTC can be used to control an external PMIC via the pmic_power_en pin,
422  * which can be configured to transition to OFF on ALARM2 events.
423  *
424  * Called with local interrupts disabled.
425  */
426 static void omap_rtc_power_off(void)
427 {
428 	struct omap_rtc *rtc = omap_rtc_power_off_rtc;
429 	struct rtc_time tm;
430 	unsigned long now;
431 	int seconds;
432 	u32 val;
433 
434 	rtc->type->unlock(rtc);
435 	/* enable pmic_power_en control */
436 	val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
437 	rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
438 
439 again:
440 	/* set alarm one second from now */
441 	omap_rtc_read_time_raw(rtc, &tm);
442 	seconds = tm.tm_sec;
443 	bcd2tm(&tm);
444 	rtc_tm_to_time(&tm, &now);
445 	rtc_time_to_tm(now + 1, &tm);
446 
447 	if (tm2bcd(&tm) < 0) {
448 		dev_err(&rtc->rtc->dev, "power off failed\n");
449 		rtc->type->lock(rtc);
450 		return;
451 	}
452 
453 	rtc_wait_not_busy(rtc);
454 
455 	rtc_write(rtc, OMAP_RTC_ALARM2_SECONDS_REG, tm.tm_sec);
456 	rtc_write(rtc, OMAP_RTC_ALARM2_MINUTES_REG, tm.tm_min);
457 	rtc_write(rtc, OMAP_RTC_ALARM2_HOURS_REG, tm.tm_hour);
458 	rtc_write(rtc, OMAP_RTC_ALARM2_DAYS_REG, tm.tm_mday);
459 	rtc_write(rtc, OMAP_RTC_ALARM2_MONTHS_REG, tm.tm_mon);
460 	rtc_write(rtc, OMAP_RTC_ALARM2_YEARS_REG, tm.tm_year);
461 
462 	/*
463 	 * enable ALARM2 interrupt
464 	 *
465 	 * NOTE: this fails on AM3352 if rtc_write (writeb) is used
466 	 */
467 	val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
468 	rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
469 			val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
470 
471 	/* Retry in case roll over happened before alarm was armed. */
472 	if (rtc_read(rtc, OMAP_RTC_SECONDS_REG) != seconds) {
473 		val = rtc_read(rtc, OMAP_RTC_STATUS_REG);
474 		if (!(val & OMAP_RTC_STATUS_ALARM2))
475 			goto again;
476 	}
477 
478 	rtc->type->lock(rtc);
479 
480 	/*
481 	 * Wait for alarm to trigger (within one second) and external PMIC to
482 	 * power off the system. Add a 500 ms margin for external latencies
483 	 * (e.g. debounce circuits).
484 	 */
485 	mdelay(1500);
486 }
487 
488 static const struct rtc_class_ops omap_rtc_ops = {
489 	.read_time	= omap_rtc_read_time,
490 	.set_time	= omap_rtc_set_time,
491 	.read_alarm	= omap_rtc_read_alarm,
492 	.set_alarm	= omap_rtc_set_alarm,
493 	.alarm_irq_enable = omap_rtc_alarm_irq_enable,
494 };
495 
496 static const struct omap_rtc_device_type omap_rtc_default_type = {
497 	.has_power_up_reset = true,
498 	.lock		= default_rtc_lock,
499 	.unlock		= default_rtc_unlock,
500 };
501 
502 static const struct omap_rtc_device_type omap_rtc_am3352_type = {
503 	.has_32kclk_en	= true,
504 	.has_irqwakeen	= true,
505 	.has_pmic_mode	= true,
506 	.lock		= am3352_rtc_lock,
507 	.unlock		= am3352_rtc_unlock,
508 };
509 
510 static const struct omap_rtc_device_type omap_rtc_da830_type = {
511 	.lock		= am3352_rtc_lock,
512 	.unlock		= am3352_rtc_unlock,
513 };
514 
515 static const struct platform_device_id omap_rtc_id_table[] = {
516 	{
517 		.name	= "omap_rtc",
518 		.driver_data = (kernel_ulong_t)&omap_rtc_default_type,
519 	}, {
520 		.name	= "am3352-rtc",
521 		.driver_data = (kernel_ulong_t)&omap_rtc_am3352_type,
522 	}, {
523 		.name	= "da830-rtc",
524 		.driver_data = (kernel_ulong_t)&omap_rtc_da830_type,
525 	}, {
526 		/* sentinel */
527 	}
528 };
529 MODULE_DEVICE_TABLE(platform, omap_rtc_id_table);
530 
531 static const struct of_device_id omap_rtc_of_match[] = {
532 	{
533 		.compatible	= "ti,am3352-rtc",
534 		.data		= &omap_rtc_am3352_type,
535 	}, {
536 		.compatible	= "ti,da830-rtc",
537 		.data		= &omap_rtc_da830_type,
538 	}, {
539 		/* sentinel */
540 	}
541 };
542 MODULE_DEVICE_TABLE(of, omap_rtc_of_match);
543 
544 static const struct pinctrl_pin_desc rtc_pins_desc[] = {
545 	PINCTRL_PIN(0, "ext_wakeup0"),
546 	PINCTRL_PIN(1, "ext_wakeup1"),
547 	PINCTRL_PIN(2, "ext_wakeup2"),
548 	PINCTRL_PIN(3, "ext_wakeup3"),
549 };
550 
551 static int rtc_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
552 {
553 	return 0;
554 }
555 
556 static const char *rtc_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
557 					unsigned int group)
558 {
559 	return NULL;
560 }
561 
562 static const struct pinctrl_ops rtc_pinctrl_ops = {
563 	.get_groups_count = rtc_pinctrl_get_groups_count,
564 	.get_group_name = rtc_pinctrl_get_group_name,
565 	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
566 	.dt_free_map = pinconf_generic_dt_free_map,
567 };
568 
569 #define PIN_CONFIG_ACTIVE_HIGH		(PIN_CONFIG_END + 1)
570 
571 static const struct pinconf_generic_params rtc_params[] = {
572 	{"ti,active-high", PIN_CONFIG_ACTIVE_HIGH, 0},
573 };
574 
575 #ifdef CONFIG_DEBUG_FS
576 static const struct pin_config_item rtc_conf_items[ARRAY_SIZE(rtc_params)] = {
577 	PCONFDUMP(PIN_CONFIG_ACTIVE_HIGH, "input active high", NULL, false),
578 };
579 #endif
580 
581 static int rtc_pinconf_get(struct pinctrl_dev *pctldev,
582 			unsigned int pin, unsigned long *config)
583 {
584 	struct omap_rtc *rtc = pinctrl_dev_get_drvdata(pctldev);
585 	unsigned int param = pinconf_to_config_param(*config);
586 	u32 val;
587 	u16 arg = 0;
588 
589 	val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
590 
591 	switch (param) {
592 	case PIN_CONFIG_INPUT_ENABLE:
593 		if (!(val & OMAP_RTC_PMIC_EXT_WKUP_EN(pin)))
594 			return -EINVAL;
595 		break;
596 	case PIN_CONFIG_ACTIVE_HIGH:
597 		if (val & OMAP_RTC_PMIC_EXT_WKUP_POL(pin))
598 			return -EINVAL;
599 		break;
600 	default:
601 		return -ENOTSUPP;
602 	};
603 
604 	*config = pinconf_to_config_packed(param, arg);
605 
606 	return 0;
607 }
608 
609 static int rtc_pinconf_set(struct pinctrl_dev *pctldev,
610 			unsigned int pin, unsigned long *configs,
611 			unsigned int num_configs)
612 {
613 	struct omap_rtc *rtc = pinctrl_dev_get_drvdata(pctldev);
614 	u32 val;
615 	unsigned int param;
616 	u32 param_val;
617 	int i;
618 
619 	val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
620 
621 	/* active low by default */
622 	val |= OMAP_RTC_PMIC_EXT_WKUP_POL(pin);
623 
624 	for (i = 0; i < num_configs; i++) {
625 		param = pinconf_to_config_param(configs[i]);
626 		param_val = pinconf_to_config_argument(configs[i]);
627 
628 		switch (param) {
629 		case PIN_CONFIG_INPUT_ENABLE:
630 			if (param_val)
631 				val |= OMAP_RTC_PMIC_EXT_WKUP_EN(pin);
632 			else
633 				val &= ~OMAP_RTC_PMIC_EXT_WKUP_EN(pin);
634 			break;
635 		case PIN_CONFIG_ACTIVE_HIGH:
636 			val &= ~OMAP_RTC_PMIC_EXT_WKUP_POL(pin);
637 			break;
638 		default:
639 			dev_err(&rtc->rtc->dev, "Property %u not supported\n",
640 				param);
641 			return -ENOTSUPP;
642 		}
643 	}
644 
645 	rtc->type->unlock(rtc);
646 	rtc_writel(rtc, OMAP_RTC_PMIC_REG, val);
647 	rtc->type->lock(rtc);
648 
649 	return 0;
650 }
651 
652 static const struct pinconf_ops rtc_pinconf_ops = {
653 	.is_generic = true,
654 	.pin_config_get = rtc_pinconf_get,
655 	.pin_config_set = rtc_pinconf_set,
656 };
657 
658 static struct pinctrl_desc rtc_pinctrl_desc = {
659 	.pins = rtc_pins_desc,
660 	.npins = ARRAY_SIZE(rtc_pins_desc),
661 	.pctlops = &rtc_pinctrl_ops,
662 	.confops = &rtc_pinconf_ops,
663 	.custom_params = rtc_params,
664 	.num_custom_params = ARRAY_SIZE(rtc_params),
665 #ifdef CONFIG_DEBUG_FS
666 	.custom_conf_items = rtc_conf_items,
667 #endif
668 	.owner = THIS_MODULE,
669 };
670 
671 static int omap_rtc_scratch_read(void *priv, unsigned int offset, void *_val,
672 				 size_t bytes)
673 {
674 	struct omap_rtc	*rtc = priv;
675 	u32 *val = _val;
676 	int i;
677 
678 	for (i = 0; i < bytes / 4; i++)
679 		val[i] = rtc_readl(rtc,
680 				   OMAP_RTC_SCRATCH0_REG + offset + (i * 4));
681 
682 	return 0;
683 }
684 
685 static int omap_rtc_scratch_write(void *priv, unsigned int offset, void *_val,
686 				  size_t bytes)
687 {
688 	struct omap_rtc	*rtc = priv;
689 	u32 *val = _val;
690 	int i;
691 
692 	rtc->type->unlock(rtc);
693 	for (i = 0; i < bytes / 4; i++)
694 		rtc_writel(rtc,
695 			   OMAP_RTC_SCRATCH0_REG + offset + (i * 4), val[i]);
696 	rtc->type->lock(rtc);
697 
698 	return 0;
699 }
700 
701 static struct nvmem_config omap_rtc_nvmem_config = {
702 	.name = "omap_rtc_scratch",
703 	.word_size = 4,
704 	.stride = 4,
705 	.size = OMAP_RTC_KICK0_REG - OMAP_RTC_SCRATCH0_REG,
706 	.reg_read = omap_rtc_scratch_read,
707 	.reg_write = omap_rtc_scratch_write,
708 };
709 
710 static int omap_rtc_probe(struct platform_device *pdev)
711 {
712 	struct omap_rtc	*rtc;
713 	struct resource	*res;
714 	u8 reg, mask, new_ctrl;
715 	const struct platform_device_id *id_entry;
716 	const struct of_device_id *of_id;
717 	int ret;
718 
719 	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
720 	if (!rtc)
721 		return -ENOMEM;
722 
723 	of_id = of_match_device(omap_rtc_of_match, &pdev->dev);
724 	if (of_id) {
725 		rtc->type = of_id->data;
726 		rtc->is_pmic_controller = rtc->type->has_pmic_mode &&
727 			of_device_is_system_power_controller(pdev->dev.of_node);
728 	} else {
729 		id_entry = platform_get_device_id(pdev);
730 		rtc->type = (void *)id_entry->driver_data;
731 	}
732 
733 	rtc->irq_timer = platform_get_irq(pdev, 0);
734 	if (rtc->irq_timer <= 0)
735 		return -ENOENT;
736 
737 	rtc->irq_alarm = platform_get_irq(pdev, 1);
738 	if (rtc->irq_alarm <= 0)
739 		return -ENOENT;
740 
741 	rtc->clk = devm_clk_get(&pdev->dev, "ext-clk");
742 	if (!IS_ERR(rtc->clk))
743 		rtc->has_ext_clk = true;
744 	else
745 		rtc->clk = devm_clk_get(&pdev->dev, "int-clk");
746 
747 	if (!IS_ERR(rtc->clk))
748 		clk_prepare_enable(rtc->clk);
749 
750 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
751 	rtc->base = devm_ioremap_resource(&pdev->dev, res);
752 	if (IS_ERR(rtc->base)) {
753 		clk_disable_unprepare(rtc->clk);
754 		return PTR_ERR(rtc->base);
755 	}
756 
757 	platform_set_drvdata(pdev, rtc);
758 
759 	/* Enable the clock/module so that we can access the registers */
760 	pm_runtime_enable(&pdev->dev);
761 	pm_runtime_get_sync(&pdev->dev);
762 
763 	rtc->type->unlock(rtc);
764 
765 	/*
766 	 * disable interrupts
767 	 *
768 	 * NOTE: ALARM2 is not cleared on AM3352 if rtc_write (writeb) is used
769 	 */
770 	rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
771 
772 	/* enable RTC functional clock */
773 	if (rtc->type->has_32kclk_en) {
774 		reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
775 		rtc_writel(rtc, OMAP_RTC_OSC_REG,
776 				reg | OMAP_RTC_OSC_32KCLK_EN);
777 	}
778 
779 	/* clear old status */
780 	reg = rtc_read(rtc, OMAP_RTC_STATUS_REG);
781 
782 	mask = OMAP_RTC_STATUS_ALARM;
783 
784 	if (rtc->type->has_pmic_mode)
785 		mask |= OMAP_RTC_STATUS_ALARM2;
786 
787 	if (rtc->type->has_power_up_reset) {
788 		mask |= OMAP_RTC_STATUS_POWER_UP;
789 		if (reg & OMAP_RTC_STATUS_POWER_UP)
790 			dev_info(&pdev->dev, "RTC power up reset detected\n");
791 	}
792 
793 	if (reg & mask)
794 		rtc_write(rtc, OMAP_RTC_STATUS_REG, reg & mask);
795 
796 	/* On boards with split power, RTC_ON_NOFF won't reset the RTC */
797 	reg = rtc_read(rtc, OMAP_RTC_CTRL_REG);
798 	if (reg & OMAP_RTC_CTRL_STOP)
799 		dev_info(&pdev->dev, "already running\n");
800 
801 	/* force to 24 hour mode */
802 	new_ctrl = reg & (OMAP_RTC_CTRL_SPLIT | OMAP_RTC_CTRL_AUTO_COMP);
803 	new_ctrl |= OMAP_RTC_CTRL_STOP;
804 
805 	/*
806 	 * BOARD-SPECIFIC CUSTOMIZATION CAN GO HERE:
807 	 *
808 	 *  - Device wake-up capability setting should come through chip
809 	 *    init logic. OMAP1 boards should initialize the "wakeup capable"
810 	 *    flag in the platform device if the board is wired right for
811 	 *    being woken up by RTC alarm. For OMAP-L138, this capability
812 	 *    is built into the SoC by the "Deep Sleep" capability.
813 	 *
814 	 *  - Boards wired so RTC_ON_nOFF is used as the reset signal,
815 	 *    rather than nPWRON_RESET, should forcibly enable split
816 	 *    power mode.  (Some chip errata report that RTC_CTRL_SPLIT
817 	 *    is write-only, and always reads as zero...)
818 	 */
819 
820 	if (new_ctrl & OMAP_RTC_CTRL_SPLIT)
821 		dev_info(&pdev->dev, "split power mode\n");
822 
823 	if (reg != new_ctrl)
824 		rtc_write(rtc, OMAP_RTC_CTRL_REG, new_ctrl);
825 
826 	/*
827 	 * If we have the external clock then switch to it so we can keep
828 	 * ticking across suspend.
829 	 */
830 	if (rtc->has_ext_clk) {
831 		reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
832 		reg &= ~OMAP_RTC_OSC_OSC32K_GZ_DISABLE;
833 		reg |= OMAP_RTC_OSC_32KCLK_EN | OMAP_RTC_OSC_SEL_32KCLK_SRC;
834 		rtc_writel(rtc, OMAP_RTC_OSC_REG, reg);
835 	}
836 
837 	rtc->type->lock(rtc);
838 
839 	device_init_wakeup(&pdev->dev, true);
840 
841 	rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
842 	if (IS_ERR(rtc->rtc)) {
843 		ret = PTR_ERR(rtc->rtc);
844 		goto err;
845 	}
846 
847 	rtc->rtc->ops = &omap_rtc_ops;
848 	omap_rtc_nvmem_config.priv = rtc;
849 
850 	/* handle periodic and alarm irqs */
851 	ret = devm_request_irq(&pdev->dev, rtc->irq_timer, rtc_irq, 0,
852 			dev_name(&rtc->rtc->dev), rtc);
853 	if (ret)
854 		goto err;
855 
856 	if (rtc->irq_timer != rtc->irq_alarm) {
857 		ret = devm_request_irq(&pdev->dev, rtc->irq_alarm, rtc_irq, 0,
858 				dev_name(&rtc->rtc->dev), rtc);
859 		if (ret)
860 			goto err;
861 	}
862 
863 	/* Support ext_wakeup pinconf */
864 	rtc_pinctrl_desc.name = dev_name(&pdev->dev);
865 
866 	rtc->pctldev = pinctrl_register(&rtc_pinctrl_desc, &pdev->dev, rtc);
867 	if (IS_ERR(rtc->pctldev)) {
868 		dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
869 		ret = PTR_ERR(rtc->pctldev);
870 		goto err;
871 	}
872 
873 	ret = rtc_register_device(rtc->rtc);
874 	if (ret)
875 		goto err_deregister_pinctrl;
876 
877 	rtc_nvmem_register(rtc->rtc, &omap_rtc_nvmem_config);
878 
879 	if (rtc->is_pmic_controller) {
880 		if (!pm_power_off) {
881 			omap_rtc_power_off_rtc = rtc;
882 			pm_power_off = omap_rtc_power_off;
883 		}
884 	}
885 
886 	return 0;
887 
888 err_deregister_pinctrl:
889 	pinctrl_unregister(rtc->pctldev);
890 err:
891 	clk_disable_unprepare(rtc->clk);
892 	device_init_wakeup(&pdev->dev, false);
893 	rtc->type->lock(rtc);
894 	pm_runtime_put_sync(&pdev->dev);
895 	pm_runtime_disable(&pdev->dev);
896 
897 	return ret;
898 }
899 
900 static int omap_rtc_remove(struct platform_device *pdev)
901 {
902 	struct omap_rtc *rtc = platform_get_drvdata(pdev);
903 	u8 reg;
904 
905 	if (pm_power_off == omap_rtc_power_off &&
906 			omap_rtc_power_off_rtc == rtc) {
907 		pm_power_off = NULL;
908 		omap_rtc_power_off_rtc = NULL;
909 	}
910 
911 	device_init_wakeup(&pdev->dev, 0);
912 
913 	if (!IS_ERR(rtc->clk))
914 		clk_disable_unprepare(rtc->clk);
915 
916 	rtc->type->unlock(rtc);
917 	/* leave rtc running, but disable irqs */
918 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
919 
920 	if (rtc->has_ext_clk) {
921 		reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
922 		reg &= ~OMAP_RTC_OSC_SEL_32KCLK_SRC;
923 		rtc_write(rtc, OMAP_RTC_OSC_REG, reg);
924 	}
925 
926 	rtc->type->lock(rtc);
927 
928 	/* Disable the clock/module */
929 	pm_runtime_put_sync(&pdev->dev);
930 	pm_runtime_disable(&pdev->dev);
931 
932 	/* Remove ext_wakeup pinconf */
933 	pinctrl_unregister(rtc->pctldev);
934 
935 	return 0;
936 }
937 
938 static int __maybe_unused omap_rtc_suspend(struct device *dev)
939 {
940 	struct omap_rtc *rtc = dev_get_drvdata(dev);
941 
942 	rtc->interrupts_reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
943 
944 	rtc->type->unlock(rtc);
945 	/*
946 	 * FIXME: the RTC alarm is not currently acting as a wakeup event
947 	 * source on some platforms, and in fact this enable() call is just
948 	 * saving a flag that's never used...
949 	 */
950 	if (device_may_wakeup(dev))
951 		enable_irq_wake(rtc->irq_alarm);
952 	else
953 		rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
954 	rtc->type->lock(rtc);
955 
956 	rtc->is_suspending = true;
957 
958 	return 0;
959 }
960 
961 static int __maybe_unused omap_rtc_resume(struct device *dev)
962 {
963 	struct omap_rtc *rtc = dev_get_drvdata(dev);
964 
965 	rtc->type->unlock(rtc);
966 	if (device_may_wakeup(dev))
967 		disable_irq_wake(rtc->irq_alarm);
968 	else
969 		rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, rtc->interrupts_reg);
970 	rtc->type->lock(rtc);
971 
972 	rtc->is_suspending = false;
973 
974 	return 0;
975 }
976 
977 static int __maybe_unused omap_rtc_runtime_suspend(struct device *dev)
978 {
979 	struct omap_rtc *rtc = dev_get_drvdata(dev);
980 
981 	if (rtc->is_suspending && !rtc->has_ext_clk)
982 		return -EBUSY;
983 
984 	return 0;
985 }
986 
987 static const struct dev_pm_ops omap_rtc_pm_ops = {
988 	SET_SYSTEM_SLEEP_PM_OPS(omap_rtc_suspend, omap_rtc_resume)
989 	SET_RUNTIME_PM_OPS(omap_rtc_runtime_suspend, NULL, NULL)
990 };
991 
992 static void omap_rtc_shutdown(struct platform_device *pdev)
993 {
994 	struct omap_rtc *rtc = platform_get_drvdata(pdev);
995 	u8 mask;
996 
997 	/*
998 	 * Keep the ALARM interrupt enabled to allow the system to power up on
999 	 * alarm events.
1000 	 */
1001 	rtc->type->unlock(rtc);
1002 	mask = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
1003 	mask &= OMAP_RTC_INTERRUPTS_IT_ALARM;
1004 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, mask);
1005 	rtc->type->lock(rtc);
1006 }
1007 
1008 static struct platform_driver omap_rtc_driver = {
1009 	.probe		= omap_rtc_probe,
1010 	.remove		= omap_rtc_remove,
1011 	.shutdown	= omap_rtc_shutdown,
1012 	.driver		= {
1013 		.name	= "omap_rtc",
1014 		.pm	= &omap_rtc_pm_ops,
1015 		.of_match_table = omap_rtc_of_match,
1016 	},
1017 	.id_table	= omap_rtc_id_table,
1018 };
1019 
1020 module_platform_driver(omap_rtc_driver);
1021 
1022 MODULE_ALIAS("platform:omap_rtc");
1023 MODULE_AUTHOR("George G. Davis (and others)");
1024 MODULE_LICENSE("GPL");
1025