xref: /openbmc/linux/drivers/rtc/rtc-omap.c (revision 752beb5e)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * TI OMAP Real Time Clock interface for Linux
4  *
5  * Copyright (C) 2003 MontaVista Software, Inc.
6  * Author: George G. Davis <gdavis@mvista.com> or <source@mvista.com>
7  *
8  * Copyright (C) 2006 David Brownell (new RTC framework)
9  * Copyright (C) 2014 Johan Hovold <johan@kernel.org>
10  */
11 
12 #include <dt-bindings/gpio/gpio.h>
13 #include <linux/bcd.h>
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/init.h>
17 #include <linux/io.h>
18 #include <linux/ioport.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/of_device.h>
23 #include <linux/pinctrl/pinctrl.h>
24 #include <linux/pinctrl/pinconf.h>
25 #include <linux/pinctrl/pinconf-generic.h>
26 #include <linux/platform_device.h>
27 #include <linux/pm_runtime.h>
28 #include <linux/rtc.h>
29 
30 /*
31  * The OMAP RTC is a year/month/day/hours/minutes/seconds BCD clock
32  * with century-range alarm matching, driven by the 32kHz clock.
33  *
34  * The main user-visible ways it differs from PC RTCs are by omitting
35  * "don't care" alarm fields and sub-second periodic IRQs, and having
36  * an autoadjust mechanism to calibrate to the true oscillator rate.
37  *
38  * Board-specific wiring options include using split power mode with
39  * RTC_OFF_NOFF used as the reset signal (so the RTC won't be reset),
40  * and wiring RTC_WAKE_INT (so the RTC alarm can wake the system from
41  * low power modes) for OMAP1 boards (OMAP-L138 has this built into
42  * the SoC). See the BOARD-SPECIFIC CUSTOMIZATION comment.
43  */
44 
45 /* RTC registers */
46 #define OMAP_RTC_SECONDS_REG		0x00
47 #define OMAP_RTC_MINUTES_REG		0x04
48 #define OMAP_RTC_HOURS_REG		0x08
49 #define OMAP_RTC_DAYS_REG		0x0C
50 #define OMAP_RTC_MONTHS_REG		0x10
51 #define OMAP_RTC_YEARS_REG		0x14
52 #define OMAP_RTC_WEEKS_REG		0x18
53 
54 #define OMAP_RTC_ALARM_SECONDS_REG	0x20
55 #define OMAP_RTC_ALARM_MINUTES_REG	0x24
56 #define OMAP_RTC_ALARM_HOURS_REG	0x28
57 #define OMAP_RTC_ALARM_DAYS_REG		0x2c
58 #define OMAP_RTC_ALARM_MONTHS_REG	0x30
59 #define OMAP_RTC_ALARM_YEARS_REG	0x34
60 
61 #define OMAP_RTC_CTRL_REG		0x40
62 #define OMAP_RTC_STATUS_REG		0x44
63 #define OMAP_RTC_INTERRUPTS_REG		0x48
64 
65 #define OMAP_RTC_COMP_LSB_REG		0x4c
66 #define OMAP_RTC_COMP_MSB_REG		0x50
67 #define OMAP_RTC_OSC_REG		0x54
68 
69 #define OMAP_RTC_SCRATCH0_REG		0x60
70 #define OMAP_RTC_SCRATCH1_REG		0x64
71 #define OMAP_RTC_SCRATCH2_REG		0x68
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 void tm2bcd(struct rtc_time *tm)
271 {
272 	tm->tm_sec = bin2bcd(tm->tm_sec);
273 	tm->tm_min = bin2bcd(tm->tm_min);
274 	tm->tm_hour = bin2bcd(tm->tm_hour);
275 	tm->tm_mday = bin2bcd(tm->tm_mday);
276 
277 	tm->tm_mon = bin2bcd(tm->tm_mon + 1);
278 	tm->tm_year = bin2bcd(tm->tm_year - 100);
279 }
280 
281 static void bcd2tm(struct rtc_time *tm)
282 {
283 	tm->tm_sec = bcd2bin(tm->tm_sec);
284 	tm->tm_min = bcd2bin(tm->tm_min);
285 	tm->tm_hour = bcd2bin(tm->tm_hour);
286 	tm->tm_mday = bcd2bin(tm->tm_mday);
287 	tm->tm_mon = bcd2bin(tm->tm_mon) - 1;
288 	/* epoch == 1900 */
289 	tm->tm_year = bcd2bin(tm->tm_year) + 100;
290 }
291 
292 static void omap_rtc_read_time_raw(struct omap_rtc *rtc, struct rtc_time *tm)
293 {
294 	tm->tm_sec = rtc_read(rtc, OMAP_RTC_SECONDS_REG);
295 	tm->tm_min = rtc_read(rtc, OMAP_RTC_MINUTES_REG);
296 	tm->tm_hour = rtc_read(rtc, OMAP_RTC_HOURS_REG);
297 	tm->tm_mday = rtc_read(rtc, OMAP_RTC_DAYS_REG);
298 	tm->tm_mon = rtc_read(rtc, OMAP_RTC_MONTHS_REG);
299 	tm->tm_year = rtc_read(rtc, OMAP_RTC_YEARS_REG);
300 }
301 
302 static int omap_rtc_read_time(struct device *dev, struct rtc_time *tm)
303 {
304 	struct omap_rtc *rtc = dev_get_drvdata(dev);
305 
306 	/* we don't report wday/yday/isdst ... */
307 	local_irq_disable();
308 	rtc_wait_not_busy(rtc);
309 	omap_rtc_read_time_raw(rtc, tm);
310 	local_irq_enable();
311 
312 	bcd2tm(tm);
313 
314 	return 0;
315 }
316 
317 static int omap_rtc_set_time(struct device *dev, struct rtc_time *tm)
318 {
319 	struct omap_rtc *rtc = dev_get_drvdata(dev);
320 
321 	tm2bcd(tm);
322 
323 	local_irq_disable();
324 	rtc_wait_not_busy(rtc);
325 
326 	rtc->type->unlock(rtc);
327 	rtc_write(rtc, OMAP_RTC_YEARS_REG, tm->tm_year);
328 	rtc_write(rtc, OMAP_RTC_MONTHS_REG, tm->tm_mon);
329 	rtc_write(rtc, OMAP_RTC_DAYS_REG, tm->tm_mday);
330 	rtc_write(rtc, OMAP_RTC_HOURS_REG, tm->tm_hour);
331 	rtc_write(rtc, OMAP_RTC_MINUTES_REG, tm->tm_min);
332 	rtc_write(rtc, OMAP_RTC_SECONDS_REG, tm->tm_sec);
333 	rtc->type->lock(rtc);
334 
335 	local_irq_enable();
336 
337 	return 0;
338 }
339 
340 static int omap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
341 {
342 	struct omap_rtc *rtc = dev_get_drvdata(dev);
343 	u8 interrupts;
344 
345 	local_irq_disable();
346 	rtc_wait_not_busy(rtc);
347 
348 	alm->time.tm_sec = rtc_read(rtc, OMAP_RTC_ALARM_SECONDS_REG);
349 	alm->time.tm_min = rtc_read(rtc, OMAP_RTC_ALARM_MINUTES_REG);
350 	alm->time.tm_hour = rtc_read(rtc, OMAP_RTC_ALARM_HOURS_REG);
351 	alm->time.tm_mday = rtc_read(rtc, OMAP_RTC_ALARM_DAYS_REG);
352 	alm->time.tm_mon = rtc_read(rtc, OMAP_RTC_ALARM_MONTHS_REG);
353 	alm->time.tm_year = rtc_read(rtc, OMAP_RTC_ALARM_YEARS_REG);
354 
355 	local_irq_enable();
356 
357 	bcd2tm(&alm->time);
358 
359 	interrupts = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
360 	alm->enabled = !!(interrupts & OMAP_RTC_INTERRUPTS_IT_ALARM);
361 
362 	return 0;
363 }
364 
365 static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
366 {
367 	struct omap_rtc *rtc = dev_get_drvdata(dev);
368 	u8 reg, irqwake_reg = 0;
369 
370 	tm2bcd(&alm->time);
371 
372 	local_irq_disable();
373 	rtc_wait_not_busy(rtc);
374 
375 	rtc->type->unlock(rtc);
376 	rtc_write(rtc, OMAP_RTC_ALARM_YEARS_REG, alm->time.tm_year);
377 	rtc_write(rtc, OMAP_RTC_ALARM_MONTHS_REG, alm->time.tm_mon);
378 	rtc_write(rtc, OMAP_RTC_ALARM_DAYS_REG, alm->time.tm_mday);
379 	rtc_write(rtc, OMAP_RTC_ALARM_HOURS_REG, alm->time.tm_hour);
380 	rtc_write(rtc, OMAP_RTC_ALARM_MINUTES_REG, alm->time.tm_min);
381 	rtc_write(rtc, OMAP_RTC_ALARM_SECONDS_REG, alm->time.tm_sec);
382 
383 	reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
384 	if (rtc->type->has_irqwakeen)
385 		irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);
386 
387 	if (alm->enabled) {
388 		reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
389 		irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
390 	} else {
391 		reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
392 		irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
393 	}
394 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
395 	if (rtc->type->has_irqwakeen)
396 		rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
397 	rtc->type->lock(rtc);
398 
399 	local_irq_enable();
400 
401 	return 0;
402 }
403 
404 static struct omap_rtc *omap_rtc_power_off_rtc;
405 
406 /*
407  * omap_rtc_poweroff: RTC-controlled power off
408  *
409  * The RTC can be used to control an external PMIC via the pmic_power_en pin,
410  * which can be configured to transition to OFF on ALARM2 events.
411  *
412  * Called with local interrupts disabled.
413  */
414 static void omap_rtc_power_off(void)
415 {
416 	struct omap_rtc *rtc = omap_rtc_power_off_rtc;
417 	struct rtc_time tm;
418 	unsigned long now;
419 	int seconds;
420 	u32 val;
421 
422 	rtc->type->unlock(rtc);
423 	/* enable pmic_power_en control */
424 	val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
425 	rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
426 
427 again:
428 	/* set alarm one second from now */
429 	omap_rtc_read_time_raw(rtc, &tm);
430 	seconds = tm.tm_sec;
431 	bcd2tm(&tm);
432 	now = rtc_tm_to_time64(&tm);
433 	rtc_time64_to_tm(now + 1, &tm);
434 
435 	tm2bcd(&tm);
436 
437 	rtc_wait_not_busy(rtc);
438 
439 	rtc_write(rtc, OMAP_RTC_ALARM2_SECONDS_REG, tm.tm_sec);
440 	rtc_write(rtc, OMAP_RTC_ALARM2_MINUTES_REG, tm.tm_min);
441 	rtc_write(rtc, OMAP_RTC_ALARM2_HOURS_REG, tm.tm_hour);
442 	rtc_write(rtc, OMAP_RTC_ALARM2_DAYS_REG, tm.tm_mday);
443 	rtc_write(rtc, OMAP_RTC_ALARM2_MONTHS_REG, tm.tm_mon);
444 	rtc_write(rtc, OMAP_RTC_ALARM2_YEARS_REG, tm.tm_year);
445 
446 	/*
447 	 * enable ALARM2 interrupt
448 	 *
449 	 * NOTE: this fails on AM3352 if rtc_write (writeb) is used
450 	 */
451 	val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
452 	rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
453 			val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
454 
455 	/* Retry in case roll over happened before alarm was armed. */
456 	if (rtc_read(rtc, OMAP_RTC_SECONDS_REG) != seconds) {
457 		val = rtc_read(rtc, OMAP_RTC_STATUS_REG);
458 		if (!(val & OMAP_RTC_STATUS_ALARM2))
459 			goto again;
460 	}
461 
462 	rtc->type->lock(rtc);
463 
464 	/*
465 	 * Wait for alarm to trigger (within one second) and external PMIC to
466 	 * power off the system. Add a 500 ms margin for external latencies
467 	 * (e.g. debounce circuits).
468 	 */
469 	mdelay(1500);
470 }
471 
472 static const struct rtc_class_ops omap_rtc_ops = {
473 	.read_time	= omap_rtc_read_time,
474 	.set_time	= omap_rtc_set_time,
475 	.read_alarm	= omap_rtc_read_alarm,
476 	.set_alarm	= omap_rtc_set_alarm,
477 	.alarm_irq_enable = omap_rtc_alarm_irq_enable,
478 };
479 
480 static const struct omap_rtc_device_type omap_rtc_default_type = {
481 	.has_power_up_reset = true,
482 	.lock		= default_rtc_lock,
483 	.unlock		= default_rtc_unlock,
484 };
485 
486 static const struct omap_rtc_device_type omap_rtc_am3352_type = {
487 	.has_32kclk_en	= true,
488 	.has_irqwakeen	= true,
489 	.has_pmic_mode	= true,
490 	.lock		= am3352_rtc_lock,
491 	.unlock		= am3352_rtc_unlock,
492 };
493 
494 static const struct omap_rtc_device_type omap_rtc_da830_type = {
495 	.lock		= am3352_rtc_lock,
496 	.unlock		= am3352_rtc_unlock,
497 };
498 
499 static const struct platform_device_id omap_rtc_id_table[] = {
500 	{
501 		.name	= "omap_rtc",
502 		.driver_data = (kernel_ulong_t)&omap_rtc_default_type,
503 	}, {
504 		.name	= "am3352-rtc",
505 		.driver_data = (kernel_ulong_t)&omap_rtc_am3352_type,
506 	}, {
507 		.name	= "da830-rtc",
508 		.driver_data = (kernel_ulong_t)&omap_rtc_da830_type,
509 	}, {
510 		/* sentinel */
511 	}
512 };
513 MODULE_DEVICE_TABLE(platform, omap_rtc_id_table);
514 
515 static const struct of_device_id omap_rtc_of_match[] = {
516 	{
517 		.compatible	= "ti,am3352-rtc",
518 		.data		= &omap_rtc_am3352_type,
519 	}, {
520 		.compatible	= "ti,da830-rtc",
521 		.data		= &omap_rtc_da830_type,
522 	}, {
523 		/* sentinel */
524 	}
525 };
526 MODULE_DEVICE_TABLE(of, omap_rtc_of_match);
527 
528 static const struct pinctrl_pin_desc rtc_pins_desc[] = {
529 	PINCTRL_PIN(0, "ext_wakeup0"),
530 	PINCTRL_PIN(1, "ext_wakeup1"),
531 	PINCTRL_PIN(2, "ext_wakeup2"),
532 	PINCTRL_PIN(3, "ext_wakeup3"),
533 };
534 
535 static int rtc_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
536 {
537 	return 0;
538 }
539 
540 static const char *rtc_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
541 					unsigned int group)
542 {
543 	return NULL;
544 }
545 
546 static const struct pinctrl_ops rtc_pinctrl_ops = {
547 	.get_groups_count = rtc_pinctrl_get_groups_count,
548 	.get_group_name = rtc_pinctrl_get_group_name,
549 	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
550 	.dt_free_map = pinconf_generic_dt_free_map,
551 };
552 
553 #define PIN_CONFIG_ACTIVE_HIGH		(PIN_CONFIG_END + 1)
554 
555 static const struct pinconf_generic_params rtc_params[] = {
556 	{"ti,active-high", PIN_CONFIG_ACTIVE_HIGH, 0},
557 };
558 
559 #ifdef CONFIG_DEBUG_FS
560 static const struct pin_config_item rtc_conf_items[ARRAY_SIZE(rtc_params)] = {
561 	PCONFDUMP(PIN_CONFIG_ACTIVE_HIGH, "input active high", NULL, false),
562 };
563 #endif
564 
565 static int rtc_pinconf_get(struct pinctrl_dev *pctldev,
566 			unsigned int pin, unsigned long *config)
567 {
568 	struct omap_rtc *rtc = pinctrl_dev_get_drvdata(pctldev);
569 	unsigned int param = pinconf_to_config_param(*config);
570 	u32 val;
571 	u16 arg = 0;
572 
573 	val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
574 
575 	switch (param) {
576 	case PIN_CONFIG_INPUT_ENABLE:
577 		if (!(val & OMAP_RTC_PMIC_EXT_WKUP_EN(pin)))
578 			return -EINVAL;
579 		break;
580 	case PIN_CONFIG_ACTIVE_HIGH:
581 		if (val & OMAP_RTC_PMIC_EXT_WKUP_POL(pin))
582 			return -EINVAL;
583 		break;
584 	default:
585 		return -ENOTSUPP;
586 	};
587 
588 	*config = pinconf_to_config_packed(param, arg);
589 
590 	return 0;
591 }
592 
593 static int rtc_pinconf_set(struct pinctrl_dev *pctldev,
594 			unsigned int pin, unsigned long *configs,
595 			unsigned int num_configs)
596 {
597 	struct omap_rtc *rtc = pinctrl_dev_get_drvdata(pctldev);
598 	u32 val;
599 	unsigned int param;
600 	u32 param_val;
601 	int i;
602 
603 	val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
604 
605 	/* active low by default */
606 	val |= OMAP_RTC_PMIC_EXT_WKUP_POL(pin);
607 
608 	for (i = 0; i < num_configs; i++) {
609 		param = pinconf_to_config_param(configs[i]);
610 		param_val = pinconf_to_config_argument(configs[i]);
611 
612 		switch (param) {
613 		case PIN_CONFIG_INPUT_ENABLE:
614 			if (param_val)
615 				val |= OMAP_RTC_PMIC_EXT_WKUP_EN(pin);
616 			else
617 				val &= ~OMAP_RTC_PMIC_EXT_WKUP_EN(pin);
618 			break;
619 		case PIN_CONFIG_ACTIVE_HIGH:
620 			val &= ~OMAP_RTC_PMIC_EXT_WKUP_POL(pin);
621 			break;
622 		default:
623 			dev_err(&rtc->rtc->dev, "Property %u not supported\n",
624 				param);
625 			return -ENOTSUPP;
626 		}
627 	}
628 
629 	rtc->type->unlock(rtc);
630 	rtc_writel(rtc, OMAP_RTC_PMIC_REG, val);
631 	rtc->type->lock(rtc);
632 
633 	return 0;
634 }
635 
636 static const struct pinconf_ops rtc_pinconf_ops = {
637 	.is_generic = true,
638 	.pin_config_get = rtc_pinconf_get,
639 	.pin_config_set = rtc_pinconf_set,
640 };
641 
642 static struct pinctrl_desc rtc_pinctrl_desc = {
643 	.pins = rtc_pins_desc,
644 	.npins = ARRAY_SIZE(rtc_pins_desc),
645 	.pctlops = &rtc_pinctrl_ops,
646 	.confops = &rtc_pinconf_ops,
647 	.custom_params = rtc_params,
648 	.num_custom_params = ARRAY_SIZE(rtc_params),
649 #ifdef CONFIG_DEBUG_FS
650 	.custom_conf_items = rtc_conf_items,
651 #endif
652 	.owner = THIS_MODULE,
653 };
654 
655 static int omap_rtc_scratch_read(void *priv, unsigned int offset, void *_val,
656 				 size_t bytes)
657 {
658 	struct omap_rtc	*rtc = priv;
659 	u32 *val = _val;
660 	int i;
661 
662 	for (i = 0; i < bytes / 4; i++)
663 		val[i] = rtc_readl(rtc,
664 				   OMAP_RTC_SCRATCH0_REG + offset + (i * 4));
665 
666 	return 0;
667 }
668 
669 static int omap_rtc_scratch_write(void *priv, unsigned int offset, void *_val,
670 				  size_t bytes)
671 {
672 	struct omap_rtc	*rtc = priv;
673 	u32 *val = _val;
674 	int i;
675 
676 	rtc->type->unlock(rtc);
677 	for (i = 0; i < bytes / 4; i++)
678 		rtc_writel(rtc,
679 			   OMAP_RTC_SCRATCH0_REG + offset + (i * 4), val[i]);
680 	rtc->type->lock(rtc);
681 
682 	return 0;
683 }
684 
685 static struct nvmem_config omap_rtc_nvmem_config = {
686 	.name = "omap_rtc_scratch",
687 	.word_size = 4,
688 	.stride = 4,
689 	.size = OMAP_RTC_KICK0_REG - OMAP_RTC_SCRATCH0_REG,
690 	.reg_read = omap_rtc_scratch_read,
691 	.reg_write = omap_rtc_scratch_write,
692 };
693 
694 static int omap_rtc_probe(struct platform_device *pdev)
695 {
696 	struct omap_rtc	*rtc;
697 	struct resource	*res;
698 	u8 reg, mask, new_ctrl;
699 	const struct platform_device_id *id_entry;
700 	const struct of_device_id *of_id;
701 	int ret;
702 
703 	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
704 	if (!rtc)
705 		return -ENOMEM;
706 
707 	of_id = of_match_device(omap_rtc_of_match, &pdev->dev);
708 	if (of_id) {
709 		rtc->type = of_id->data;
710 		rtc->is_pmic_controller = rtc->type->has_pmic_mode &&
711 			of_device_is_system_power_controller(pdev->dev.of_node);
712 	} else {
713 		id_entry = platform_get_device_id(pdev);
714 		rtc->type = (void *)id_entry->driver_data;
715 	}
716 
717 	rtc->irq_timer = platform_get_irq(pdev, 0);
718 	if (rtc->irq_timer <= 0)
719 		return -ENOENT;
720 
721 	rtc->irq_alarm = platform_get_irq(pdev, 1);
722 	if (rtc->irq_alarm <= 0)
723 		return -ENOENT;
724 
725 	rtc->clk = devm_clk_get(&pdev->dev, "ext-clk");
726 	if (!IS_ERR(rtc->clk))
727 		rtc->has_ext_clk = true;
728 	else
729 		rtc->clk = devm_clk_get(&pdev->dev, "int-clk");
730 
731 	if (!IS_ERR(rtc->clk))
732 		clk_prepare_enable(rtc->clk);
733 
734 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
735 	rtc->base = devm_ioremap_resource(&pdev->dev, res);
736 	if (IS_ERR(rtc->base)) {
737 		clk_disable_unprepare(rtc->clk);
738 		return PTR_ERR(rtc->base);
739 	}
740 
741 	platform_set_drvdata(pdev, rtc);
742 
743 	/* Enable the clock/module so that we can access the registers */
744 	pm_runtime_enable(&pdev->dev);
745 	pm_runtime_get_sync(&pdev->dev);
746 
747 	rtc->type->unlock(rtc);
748 
749 	/*
750 	 * disable interrupts
751 	 *
752 	 * NOTE: ALARM2 is not cleared on AM3352 if rtc_write (writeb) is used
753 	 */
754 	rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
755 
756 	/* enable RTC functional clock */
757 	if (rtc->type->has_32kclk_en) {
758 		reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
759 		rtc_writel(rtc, OMAP_RTC_OSC_REG,
760 				reg | OMAP_RTC_OSC_32KCLK_EN);
761 	}
762 
763 	/* clear old status */
764 	reg = rtc_read(rtc, OMAP_RTC_STATUS_REG);
765 
766 	mask = OMAP_RTC_STATUS_ALARM;
767 
768 	if (rtc->type->has_pmic_mode)
769 		mask |= OMAP_RTC_STATUS_ALARM2;
770 
771 	if (rtc->type->has_power_up_reset) {
772 		mask |= OMAP_RTC_STATUS_POWER_UP;
773 		if (reg & OMAP_RTC_STATUS_POWER_UP)
774 			dev_info(&pdev->dev, "RTC power up reset detected\n");
775 	}
776 
777 	if (reg & mask)
778 		rtc_write(rtc, OMAP_RTC_STATUS_REG, reg & mask);
779 
780 	/* On boards with split power, RTC_ON_NOFF won't reset the RTC */
781 	reg = rtc_read(rtc, OMAP_RTC_CTRL_REG);
782 	if (reg & OMAP_RTC_CTRL_STOP)
783 		dev_info(&pdev->dev, "already running\n");
784 
785 	/* force to 24 hour mode */
786 	new_ctrl = reg & (OMAP_RTC_CTRL_SPLIT | OMAP_RTC_CTRL_AUTO_COMP);
787 	new_ctrl |= OMAP_RTC_CTRL_STOP;
788 
789 	/*
790 	 * BOARD-SPECIFIC CUSTOMIZATION CAN GO HERE:
791 	 *
792 	 *  - Device wake-up capability setting should come through chip
793 	 *    init logic. OMAP1 boards should initialize the "wakeup capable"
794 	 *    flag in the platform device if the board is wired right for
795 	 *    being woken up by RTC alarm. For OMAP-L138, this capability
796 	 *    is built into the SoC by the "Deep Sleep" capability.
797 	 *
798 	 *  - Boards wired so RTC_ON_nOFF is used as the reset signal,
799 	 *    rather than nPWRON_RESET, should forcibly enable split
800 	 *    power mode.  (Some chip errata report that RTC_CTRL_SPLIT
801 	 *    is write-only, and always reads as zero...)
802 	 */
803 
804 	if (new_ctrl & OMAP_RTC_CTRL_SPLIT)
805 		dev_info(&pdev->dev, "split power mode\n");
806 
807 	if (reg != new_ctrl)
808 		rtc_write(rtc, OMAP_RTC_CTRL_REG, new_ctrl);
809 
810 	/*
811 	 * If we have the external clock then switch to it so we can keep
812 	 * ticking across suspend.
813 	 */
814 	if (rtc->has_ext_clk) {
815 		reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
816 		reg &= ~OMAP_RTC_OSC_OSC32K_GZ_DISABLE;
817 		reg |= OMAP_RTC_OSC_32KCLK_EN | OMAP_RTC_OSC_SEL_32KCLK_SRC;
818 		rtc_writel(rtc, OMAP_RTC_OSC_REG, reg);
819 	}
820 
821 	rtc->type->lock(rtc);
822 
823 	device_init_wakeup(&pdev->dev, true);
824 
825 	rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
826 	if (IS_ERR(rtc->rtc)) {
827 		ret = PTR_ERR(rtc->rtc);
828 		goto err;
829 	}
830 
831 	rtc->rtc->ops = &omap_rtc_ops;
832 	rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
833 	rtc->rtc->range_max = RTC_TIMESTAMP_END_2099;
834 	omap_rtc_nvmem_config.priv = rtc;
835 
836 	/* handle periodic and alarm irqs */
837 	ret = devm_request_irq(&pdev->dev, rtc->irq_timer, rtc_irq, 0,
838 			dev_name(&rtc->rtc->dev), rtc);
839 	if (ret)
840 		goto err;
841 
842 	if (rtc->irq_timer != rtc->irq_alarm) {
843 		ret = devm_request_irq(&pdev->dev, rtc->irq_alarm, rtc_irq, 0,
844 				dev_name(&rtc->rtc->dev), rtc);
845 		if (ret)
846 			goto err;
847 	}
848 
849 	/* Support ext_wakeup pinconf */
850 	rtc_pinctrl_desc.name = dev_name(&pdev->dev);
851 
852 	rtc->pctldev = pinctrl_register(&rtc_pinctrl_desc, &pdev->dev, rtc);
853 	if (IS_ERR(rtc->pctldev)) {
854 		dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
855 		ret = PTR_ERR(rtc->pctldev);
856 		goto err;
857 	}
858 
859 	ret = rtc_register_device(rtc->rtc);
860 	if (ret)
861 		goto err_deregister_pinctrl;
862 
863 	rtc_nvmem_register(rtc->rtc, &omap_rtc_nvmem_config);
864 
865 	if (rtc->is_pmic_controller) {
866 		if (!pm_power_off) {
867 			omap_rtc_power_off_rtc = rtc;
868 			pm_power_off = omap_rtc_power_off;
869 		}
870 	}
871 
872 	return 0;
873 
874 err_deregister_pinctrl:
875 	pinctrl_unregister(rtc->pctldev);
876 err:
877 	clk_disable_unprepare(rtc->clk);
878 	device_init_wakeup(&pdev->dev, false);
879 	rtc->type->lock(rtc);
880 	pm_runtime_put_sync(&pdev->dev);
881 	pm_runtime_disable(&pdev->dev);
882 
883 	return ret;
884 }
885 
886 static int omap_rtc_remove(struct platform_device *pdev)
887 {
888 	struct omap_rtc *rtc = platform_get_drvdata(pdev);
889 	u8 reg;
890 
891 	if (pm_power_off == omap_rtc_power_off &&
892 			omap_rtc_power_off_rtc == rtc) {
893 		pm_power_off = NULL;
894 		omap_rtc_power_off_rtc = NULL;
895 	}
896 
897 	device_init_wakeup(&pdev->dev, 0);
898 
899 	if (!IS_ERR(rtc->clk))
900 		clk_disable_unprepare(rtc->clk);
901 
902 	rtc->type->unlock(rtc);
903 	/* leave rtc running, but disable irqs */
904 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
905 
906 	if (rtc->has_ext_clk) {
907 		reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
908 		reg &= ~OMAP_RTC_OSC_SEL_32KCLK_SRC;
909 		rtc_write(rtc, OMAP_RTC_OSC_REG, reg);
910 	}
911 
912 	rtc->type->lock(rtc);
913 
914 	/* Disable the clock/module */
915 	pm_runtime_put_sync(&pdev->dev);
916 	pm_runtime_disable(&pdev->dev);
917 
918 	/* Remove ext_wakeup pinconf */
919 	pinctrl_unregister(rtc->pctldev);
920 
921 	return 0;
922 }
923 
924 static int __maybe_unused omap_rtc_suspend(struct device *dev)
925 {
926 	struct omap_rtc *rtc = dev_get_drvdata(dev);
927 
928 	rtc->interrupts_reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
929 
930 	rtc->type->unlock(rtc);
931 	/*
932 	 * FIXME: the RTC alarm is not currently acting as a wakeup event
933 	 * source on some platforms, and in fact this enable() call is just
934 	 * saving a flag that's never used...
935 	 */
936 	if (device_may_wakeup(dev))
937 		enable_irq_wake(rtc->irq_alarm);
938 	else
939 		rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
940 	rtc->type->lock(rtc);
941 
942 	rtc->is_suspending = true;
943 
944 	return 0;
945 }
946 
947 static int __maybe_unused omap_rtc_resume(struct device *dev)
948 {
949 	struct omap_rtc *rtc = dev_get_drvdata(dev);
950 
951 	rtc->type->unlock(rtc);
952 	if (device_may_wakeup(dev))
953 		disable_irq_wake(rtc->irq_alarm);
954 	else
955 		rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, rtc->interrupts_reg);
956 	rtc->type->lock(rtc);
957 
958 	rtc->is_suspending = false;
959 
960 	return 0;
961 }
962 
963 static int __maybe_unused omap_rtc_runtime_suspend(struct device *dev)
964 {
965 	struct omap_rtc *rtc = dev_get_drvdata(dev);
966 
967 	if (rtc->is_suspending && !rtc->has_ext_clk)
968 		return -EBUSY;
969 
970 	return 0;
971 }
972 
973 static const struct dev_pm_ops omap_rtc_pm_ops = {
974 	SET_SYSTEM_SLEEP_PM_OPS(omap_rtc_suspend, omap_rtc_resume)
975 	SET_RUNTIME_PM_OPS(omap_rtc_runtime_suspend, NULL, NULL)
976 };
977 
978 static void omap_rtc_shutdown(struct platform_device *pdev)
979 {
980 	struct omap_rtc *rtc = platform_get_drvdata(pdev);
981 	u8 mask;
982 
983 	/*
984 	 * Keep the ALARM interrupt enabled to allow the system to power up on
985 	 * alarm events.
986 	 */
987 	rtc->type->unlock(rtc);
988 	mask = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
989 	mask &= OMAP_RTC_INTERRUPTS_IT_ALARM;
990 	rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, mask);
991 	rtc->type->lock(rtc);
992 }
993 
994 static struct platform_driver omap_rtc_driver = {
995 	.probe		= omap_rtc_probe,
996 	.remove		= omap_rtc_remove,
997 	.shutdown	= omap_rtc_shutdown,
998 	.driver		= {
999 		.name	= "omap_rtc",
1000 		.pm	= &omap_rtc_pm_ops,
1001 		.of_match_table = omap_rtc_of_match,
1002 	},
1003 	.id_table	= omap_rtc_id_table,
1004 };
1005 
1006 module_platform_driver(omap_rtc_driver);
1007 
1008 MODULE_ALIAS("platform:omap_rtc");
1009 MODULE_AUTHOR("George G. Davis (and others)");
1010 MODULE_LICENSE("GPL");
1011