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
rtc_read(struct omap_rtc * rtc,unsigned int reg)155 static inline u8 rtc_read(struct omap_rtc *rtc, unsigned int reg)
156 {
157 return readb(rtc->base + reg);
158 }
159
rtc_readl(struct omap_rtc * rtc,unsigned int reg)160 static inline u32 rtc_readl(struct omap_rtc *rtc, unsigned int reg)
161 {
162 return readl(rtc->base + reg);
163 }
164
rtc_write(struct omap_rtc * rtc,unsigned int reg,u8 val)165 static inline void rtc_write(struct omap_rtc *rtc, unsigned int reg, u8 val)
166 {
167 writeb(val, rtc->base + reg);
168 }
169
rtc_writel(struct omap_rtc * rtc,unsigned int reg,u32 val)170 static inline void rtc_writel(struct omap_rtc *rtc, unsigned int reg, u32 val)
171 {
172 writel(val, rtc->base + reg);
173 }
174
am3352_rtc_unlock(struct omap_rtc * rtc)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
am3352_rtc_lock(struct omap_rtc * rtc)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
default_rtc_unlock(struct omap_rtc * rtc)187 static void default_rtc_unlock(struct omap_rtc *rtc)
188 {
189 }
190
default_rtc_lock(struct omap_rtc * rtc)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 */
rtc_wait_not_busy(struct omap_rtc * rtc)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
rtc_irq(int irq,void * dev_id)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
omap_rtc_alarm_irq_enable(struct device * dev,unsigned int enabled)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 */
tm2bcd(struct rtc_time * tm)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
bcd2tm(struct rtc_time * tm)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
omap_rtc_read_time_raw(struct omap_rtc * rtc,struct rtc_time * tm)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
omap_rtc_read_time(struct device * dev,struct rtc_time * tm)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
omap_rtc_set_time(struct device * dev,struct rtc_time * tm)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
omap_rtc_read_alarm(struct device * dev,struct rtc_wkalrm * alm)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
omap_rtc_set_alarm(struct device * dev,struct rtc_wkalrm * alm)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_power_off_program: Set the pmic power off sequence. The RTC
408 * generates pmic_pwr_enable control, which can be used to control an external
409 * PMIC.
410 */
omap_rtc_power_off_program(struct device * dev)411 int omap_rtc_power_off_program(struct device *dev)
412 {
413 struct omap_rtc *rtc = omap_rtc_power_off_rtc;
414 struct rtc_time tm;
415 unsigned long now;
416 int seconds;
417 u32 val;
418
419 rtc->type->unlock(rtc);
420 /* enable pmic_power_en control */
421 val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
422 rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
423
424 again:
425 /* Clear any existing ALARM2 event */
426 rtc_writel(rtc, OMAP_RTC_STATUS_REG, OMAP_RTC_STATUS_ALARM2);
427
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 return 0;
465 }
466 EXPORT_SYMBOL(omap_rtc_power_off_program);
467
468 /*
469 * omap_rtc_poweroff: RTC-controlled power off
470 *
471 * The RTC can be used to control an external PMIC via the pmic_power_en pin,
472 * which can be configured to transition to OFF on ALARM2 events.
473 *
474 * Notes:
475 * The one-second alarm offset is the shortest offset possible as the alarm
476 * registers must be set before the next timer update and the offset
477 * calculation is too heavy for everything to be done within a single access
478 * period (~15 us).
479 *
480 * Called with local interrupts disabled.
481 */
omap_rtc_power_off(void)482 static void omap_rtc_power_off(void)
483 {
484 struct rtc_device *rtc = omap_rtc_power_off_rtc->rtc;
485 u32 val;
486
487 omap_rtc_power_off_program(rtc->dev.parent);
488
489 /* Set PMIC power enable and EXT_WAKEUP in case PB power on is used */
490 omap_rtc_power_off_rtc->type->unlock(omap_rtc_power_off_rtc);
491 val = rtc_readl(omap_rtc_power_off_rtc, OMAP_RTC_PMIC_REG);
492 val |= OMAP_RTC_PMIC_POWER_EN_EN | OMAP_RTC_PMIC_EXT_WKUP_POL(0) |
493 OMAP_RTC_PMIC_EXT_WKUP_EN(0);
494 rtc_writel(omap_rtc_power_off_rtc, OMAP_RTC_PMIC_REG, val);
495 omap_rtc_power_off_rtc->type->lock(omap_rtc_power_off_rtc);
496
497 /*
498 * Wait for alarm to trigger (within one second) and external PMIC to
499 * power off the system. Add a 500 ms margin for external latencies
500 * (e.g. debounce circuits).
501 */
502 mdelay(1500);
503 }
504
505 static const struct rtc_class_ops omap_rtc_ops = {
506 .read_time = omap_rtc_read_time,
507 .set_time = omap_rtc_set_time,
508 .read_alarm = omap_rtc_read_alarm,
509 .set_alarm = omap_rtc_set_alarm,
510 .alarm_irq_enable = omap_rtc_alarm_irq_enable,
511 };
512
513 static const struct omap_rtc_device_type omap_rtc_default_type = {
514 .has_power_up_reset = true,
515 .lock = default_rtc_lock,
516 .unlock = default_rtc_unlock,
517 };
518
519 static const struct omap_rtc_device_type omap_rtc_am3352_type = {
520 .has_32kclk_en = true,
521 .has_irqwakeen = true,
522 .has_pmic_mode = true,
523 .lock = am3352_rtc_lock,
524 .unlock = am3352_rtc_unlock,
525 };
526
527 static const struct omap_rtc_device_type omap_rtc_da830_type = {
528 .lock = am3352_rtc_lock,
529 .unlock = am3352_rtc_unlock,
530 };
531
532 static const struct platform_device_id omap_rtc_id_table[] = {
533 {
534 .name = "omap_rtc",
535 .driver_data = (kernel_ulong_t)&omap_rtc_default_type,
536 }, {
537 .name = "am3352-rtc",
538 .driver_data = (kernel_ulong_t)&omap_rtc_am3352_type,
539 }, {
540 .name = "da830-rtc",
541 .driver_data = (kernel_ulong_t)&omap_rtc_da830_type,
542 }, {
543 /* sentinel */
544 }
545 };
546 MODULE_DEVICE_TABLE(platform, omap_rtc_id_table);
547
548 static const struct of_device_id omap_rtc_of_match[] = {
549 {
550 .compatible = "ti,am3352-rtc",
551 .data = &omap_rtc_am3352_type,
552 }, {
553 .compatible = "ti,da830-rtc",
554 .data = &omap_rtc_da830_type,
555 }, {
556 /* sentinel */
557 }
558 };
559 MODULE_DEVICE_TABLE(of, omap_rtc_of_match);
560
561 static const struct pinctrl_pin_desc rtc_pins_desc[] = {
562 PINCTRL_PIN(0, "ext_wakeup0"),
563 PINCTRL_PIN(1, "ext_wakeup1"),
564 PINCTRL_PIN(2, "ext_wakeup2"),
565 PINCTRL_PIN(3, "ext_wakeup3"),
566 };
567
rtc_pinctrl_get_groups_count(struct pinctrl_dev * pctldev)568 static int rtc_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
569 {
570 return 0;
571 }
572
rtc_pinctrl_get_group_name(struct pinctrl_dev * pctldev,unsigned int group)573 static const char *rtc_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
574 unsigned int group)
575 {
576 return NULL;
577 }
578
579 static const struct pinctrl_ops rtc_pinctrl_ops = {
580 .get_groups_count = rtc_pinctrl_get_groups_count,
581 .get_group_name = rtc_pinctrl_get_group_name,
582 .dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
583 .dt_free_map = pinconf_generic_dt_free_map,
584 };
585
586 #define PIN_CONFIG_ACTIVE_HIGH (PIN_CONFIG_END + 1)
587
588 static const struct pinconf_generic_params rtc_params[] = {
589 {"ti,active-high", PIN_CONFIG_ACTIVE_HIGH, 0},
590 };
591
592 #ifdef CONFIG_DEBUG_FS
593 static const struct pin_config_item rtc_conf_items[ARRAY_SIZE(rtc_params)] = {
594 PCONFDUMP(PIN_CONFIG_ACTIVE_HIGH, "input active high", NULL, false),
595 };
596 #endif
597
rtc_pinconf_get(struct pinctrl_dev * pctldev,unsigned int pin,unsigned long * config)598 static int rtc_pinconf_get(struct pinctrl_dev *pctldev,
599 unsigned int pin, unsigned long *config)
600 {
601 struct omap_rtc *rtc = pinctrl_dev_get_drvdata(pctldev);
602 unsigned int param = pinconf_to_config_param(*config);
603 u32 val;
604 u16 arg = 0;
605
606 val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
607
608 switch (param) {
609 case PIN_CONFIG_INPUT_ENABLE:
610 if (!(val & OMAP_RTC_PMIC_EXT_WKUP_EN(pin)))
611 return -EINVAL;
612 break;
613 case PIN_CONFIG_ACTIVE_HIGH:
614 if (val & OMAP_RTC_PMIC_EXT_WKUP_POL(pin))
615 return -EINVAL;
616 break;
617 default:
618 return -ENOTSUPP;
619 };
620
621 *config = pinconf_to_config_packed(param, arg);
622
623 return 0;
624 }
625
rtc_pinconf_set(struct pinctrl_dev * pctldev,unsigned int pin,unsigned long * configs,unsigned int num_configs)626 static int rtc_pinconf_set(struct pinctrl_dev *pctldev,
627 unsigned int pin, unsigned long *configs,
628 unsigned int num_configs)
629 {
630 struct omap_rtc *rtc = pinctrl_dev_get_drvdata(pctldev);
631 u32 val;
632 unsigned int param;
633 u32 param_val;
634 int i;
635
636 val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
637
638 /* active low by default */
639 val |= OMAP_RTC_PMIC_EXT_WKUP_POL(pin);
640
641 for (i = 0; i < num_configs; i++) {
642 param = pinconf_to_config_param(configs[i]);
643 param_val = pinconf_to_config_argument(configs[i]);
644
645 switch (param) {
646 case PIN_CONFIG_INPUT_ENABLE:
647 if (param_val)
648 val |= OMAP_RTC_PMIC_EXT_WKUP_EN(pin);
649 else
650 val &= ~OMAP_RTC_PMIC_EXT_WKUP_EN(pin);
651 break;
652 case PIN_CONFIG_ACTIVE_HIGH:
653 val &= ~OMAP_RTC_PMIC_EXT_WKUP_POL(pin);
654 break;
655 default:
656 dev_err(&rtc->rtc->dev, "Property %u not supported\n",
657 param);
658 return -ENOTSUPP;
659 }
660 }
661
662 rtc->type->unlock(rtc);
663 rtc_writel(rtc, OMAP_RTC_PMIC_REG, val);
664 rtc->type->lock(rtc);
665
666 return 0;
667 }
668
669 static const struct pinconf_ops rtc_pinconf_ops = {
670 .is_generic = true,
671 .pin_config_get = rtc_pinconf_get,
672 .pin_config_set = rtc_pinconf_set,
673 };
674
675 static struct pinctrl_desc rtc_pinctrl_desc = {
676 .pins = rtc_pins_desc,
677 .npins = ARRAY_SIZE(rtc_pins_desc),
678 .pctlops = &rtc_pinctrl_ops,
679 .confops = &rtc_pinconf_ops,
680 .custom_params = rtc_params,
681 .num_custom_params = ARRAY_SIZE(rtc_params),
682 #ifdef CONFIG_DEBUG_FS
683 .custom_conf_items = rtc_conf_items,
684 #endif
685 .owner = THIS_MODULE,
686 };
687
omap_rtc_scratch_read(void * priv,unsigned int offset,void * _val,size_t bytes)688 static int omap_rtc_scratch_read(void *priv, unsigned int offset, void *_val,
689 size_t bytes)
690 {
691 struct omap_rtc *rtc = priv;
692 u32 *val = _val;
693 int i;
694
695 for (i = 0; i < bytes / 4; i++)
696 val[i] = rtc_readl(rtc,
697 OMAP_RTC_SCRATCH0_REG + offset + (i * 4));
698
699 return 0;
700 }
701
omap_rtc_scratch_write(void * priv,unsigned int offset,void * _val,size_t bytes)702 static int omap_rtc_scratch_write(void *priv, unsigned int offset, void *_val,
703 size_t bytes)
704 {
705 struct omap_rtc *rtc = priv;
706 u32 *val = _val;
707 int i;
708
709 rtc->type->unlock(rtc);
710 for (i = 0; i < bytes / 4; i++)
711 rtc_writel(rtc,
712 OMAP_RTC_SCRATCH0_REG + offset + (i * 4), val[i]);
713 rtc->type->lock(rtc);
714
715 return 0;
716 }
717
718 static struct nvmem_config omap_rtc_nvmem_config = {
719 .name = "omap_rtc_scratch",
720 .word_size = 4,
721 .stride = 4,
722 .size = OMAP_RTC_KICK0_REG - OMAP_RTC_SCRATCH0_REG,
723 .reg_read = omap_rtc_scratch_read,
724 .reg_write = omap_rtc_scratch_write,
725 };
726
omap_rtc_probe(struct platform_device * pdev)727 static int omap_rtc_probe(struct platform_device *pdev)
728 {
729 struct omap_rtc *rtc;
730 struct resource *res;
731 u8 reg, mask, new_ctrl;
732 const struct platform_device_id *id_entry;
733 const struct of_device_id *of_id;
734 int ret;
735
736 rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
737 if (!rtc)
738 return -ENOMEM;
739
740 of_id = of_match_device(omap_rtc_of_match, &pdev->dev);
741 if (of_id) {
742 rtc->type = of_id->data;
743 rtc->is_pmic_controller = rtc->type->has_pmic_mode &&
744 of_device_is_system_power_controller(pdev->dev.of_node);
745 } else {
746 id_entry = platform_get_device_id(pdev);
747 rtc->type = (void *)id_entry->driver_data;
748 }
749
750 rtc->irq_timer = platform_get_irq(pdev, 0);
751 if (rtc->irq_timer <= 0)
752 return -ENOENT;
753
754 rtc->irq_alarm = platform_get_irq(pdev, 1);
755 if (rtc->irq_alarm <= 0)
756 return -ENOENT;
757
758 rtc->clk = devm_clk_get(&pdev->dev, "ext-clk");
759 if (!IS_ERR(rtc->clk))
760 rtc->has_ext_clk = true;
761 else
762 rtc->clk = devm_clk_get(&pdev->dev, "int-clk");
763
764 if (!IS_ERR(rtc->clk))
765 clk_prepare_enable(rtc->clk);
766
767 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
768 rtc->base = devm_ioremap_resource(&pdev->dev, res);
769 if (IS_ERR(rtc->base)) {
770 clk_disable_unprepare(rtc->clk);
771 return PTR_ERR(rtc->base);
772 }
773
774 platform_set_drvdata(pdev, rtc);
775
776 /* Enable the clock/module so that we can access the registers */
777 pm_runtime_enable(&pdev->dev);
778 pm_runtime_get_sync(&pdev->dev);
779
780 rtc->type->unlock(rtc);
781
782 /*
783 * disable interrupts
784 *
785 * NOTE: ALARM2 is not cleared on AM3352 if rtc_write (writeb) is used
786 */
787 rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
788
789 /* enable RTC functional clock */
790 if (rtc->type->has_32kclk_en) {
791 reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
792 rtc_writel(rtc, OMAP_RTC_OSC_REG,
793 reg | OMAP_RTC_OSC_32KCLK_EN);
794 }
795
796 /* clear old status */
797 reg = rtc_read(rtc, OMAP_RTC_STATUS_REG);
798
799 mask = OMAP_RTC_STATUS_ALARM;
800
801 if (rtc->type->has_pmic_mode)
802 mask |= OMAP_RTC_STATUS_ALARM2;
803
804 if (rtc->type->has_power_up_reset) {
805 mask |= OMAP_RTC_STATUS_POWER_UP;
806 if (reg & OMAP_RTC_STATUS_POWER_UP)
807 dev_info(&pdev->dev, "RTC power up reset detected\n");
808 }
809
810 if (reg & mask)
811 rtc_write(rtc, OMAP_RTC_STATUS_REG, reg & mask);
812
813 /* On boards with split power, RTC_ON_NOFF won't reset the RTC */
814 reg = rtc_read(rtc, OMAP_RTC_CTRL_REG);
815 if (reg & OMAP_RTC_CTRL_STOP)
816 dev_info(&pdev->dev, "already running\n");
817
818 /* force to 24 hour mode */
819 new_ctrl = reg & (OMAP_RTC_CTRL_SPLIT | OMAP_RTC_CTRL_AUTO_COMP);
820 new_ctrl |= OMAP_RTC_CTRL_STOP;
821
822 /*
823 * BOARD-SPECIFIC CUSTOMIZATION CAN GO HERE:
824 *
825 * - Device wake-up capability setting should come through chip
826 * init logic. OMAP1 boards should initialize the "wakeup capable"
827 * flag in the platform device if the board is wired right for
828 * being woken up by RTC alarm. For OMAP-L138, this capability
829 * is built into the SoC by the "Deep Sleep" capability.
830 *
831 * - Boards wired so RTC_ON_nOFF is used as the reset signal,
832 * rather than nPWRON_RESET, should forcibly enable split
833 * power mode. (Some chip errata report that RTC_CTRL_SPLIT
834 * is write-only, and always reads as zero...)
835 */
836
837 if (new_ctrl & OMAP_RTC_CTRL_SPLIT)
838 dev_info(&pdev->dev, "split power mode\n");
839
840 if (reg != new_ctrl)
841 rtc_write(rtc, OMAP_RTC_CTRL_REG, new_ctrl);
842
843 /*
844 * If we have the external clock then switch to it so we can keep
845 * ticking across suspend.
846 */
847 if (rtc->has_ext_clk) {
848 reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
849 reg &= ~OMAP_RTC_OSC_OSC32K_GZ_DISABLE;
850 reg |= OMAP_RTC_OSC_32KCLK_EN | OMAP_RTC_OSC_SEL_32KCLK_SRC;
851 rtc_writel(rtc, OMAP_RTC_OSC_REG, reg);
852 }
853
854 rtc->type->lock(rtc);
855
856 device_init_wakeup(&pdev->dev, true);
857
858 rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
859 if (IS_ERR(rtc->rtc)) {
860 ret = PTR_ERR(rtc->rtc);
861 goto err;
862 }
863
864 rtc->rtc->ops = &omap_rtc_ops;
865 rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
866 rtc->rtc->range_max = RTC_TIMESTAMP_END_2099;
867 omap_rtc_nvmem_config.priv = rtc;
868
869 /* handle periodic and alarm irqs */
870 ret = devm_request_irq(&pdev->dev, rtc->irq_timer, rtc_irq, 0,
871 dev_name(&rtc->rtc->dev), rtc);
872 if (ret)
873 goto err;
874
875 if (rtc->irq_timer != rtc->irq_alarm) {
876 ret = devm_request_irq(&pdev->dev, rtc->irq_alarm, rtc_irq, 0,
877 dev_name(&rtc->rtc->dev), rtc);
878 if (ret)
879 goto err;
880 }
881
882 /* Support ext_wakeup pinconf */
883 rtc_pinctrl_desc.name = dev_name(&pdev->dev);
884
885 rtc->pctldev = pinctrl_register(&rtc_pinctrl_desc, &pdev->dev, rtc);
886 if (IS_ERR(rtc->pctldev)) {
887 dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
888 ret = PTR_ERR(rtc->pctldev);
889 goto err;
890 }
891
892 ret = rtc_register_device(rtc->rtc);
893 if (ret)
894 goto err_deregister_pinctrl;
895
896 rtc_nvmem_register(rtc->rtc, &omap_rtc_nvmem_config);
897
898 if (rtc->is_pmic_controller) {
899 if (!pm_power_off) {
900 omap_rtc_power_off_rtc = rtc;
901 pm_power_off = omap_rtc_power_off;
902 }
903 }
904
905 return 0;
906
907 err_deregister_pinctrl:
908 pinctrl_unregister(rtc->pctldev);
909 err:
910 clk_disable_unprepare(rtc->clk);
911 device_init_wakeup(&pdev->dev, false);
912 rtc->type->lock(rtc);
913 pm_runtime_put_sync(&pdev->dev);
914 pm_runtime_disable(&pdev->dev);
915
916 return ret;
917 }
918
omap_rtc_remove(struct platform_device * pdev)919 static int omap_rtc_remove(struct platform_device *pdev)
920 {
921 struct omap_rtc *rtc = platform_get_drvdata(pdev);
922 u8 reg;
923
924 if (pm_power_off == omap_rtc_power_off &&
925 omap_rtc_power_off_rtc == rtc) {
926 pm_power_off = NULL;
927 omap_rtc_power_off_rtc = NULL;
928 }
929
930 device_init_wakeup(&pdev->dev, 0);
931
932 if (!IS_ERR(rtc->clk))
933 clk_disable_unprepare(rtc->clk);
934
935 rtc->type->unlock(rtc);
936 /* leave rtc running, but disable irqs */
937 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
938
939 if (rtc->has_ext_clk) {
940 reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
941 reg &= ~OMAP_RTC_OSC_SEL_32KCLK_SRC;
942 rtc_write(rtc, OMAP_RTC_OSC_REG, reg);
943 }
944
945 rtc->type->lock(rtc);
946
947 /* Disable the clock/module */
948 pm_runtime_put_sync(&pdev->dev);
949 pm_runtime_disable(&pdev->dev);
950
951 /* Remove ext_wakeup pinconf */
952 pinctrl_unregister(rtc->pctldev);
953
954 return 0;
955 }
956
omap_rtc_suspend(struct device * dev)957 static int __maybe_unused omap_rtc_suspend(struct device *dev)
958 {
959 struct omap_rtc *rtc = dev_get_drvdata(dev);
960
961 rtc->interrupts_reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
962
963 rtc->type->unlock(rtc);
964 /*
965 * FIXME: the RTC alarm is not currently acting as a wakeup event
966 * source on some platforms, and in fact this enable() call is just
967 * saving a flag that's never used...
968 */
969 if (device_may_wakeup(dev))
970 enable_irq_wake(rtc->irq_alarm);
971 else
972 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
973 rtc->type->lock(rtc);
974
975 rtc->is_suspending = true;
976
977 return 0;
978 }
979
omap_rtc_resume(struct device * dev)980 static int __maybe_unused omap_rtc_resume(struct device *dev)
981 {
982 struct omap_rtc *rtc = dev_get_drvdata(dev);
983
984 rtc->type->unlock(rtc);
985 if (device_may_wakeup(dev))
986 disable_irq_wake(rtc->irq_alarm);
987 else
988 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, rtc->interrupts_reg);
989 rtc->type->lock(rtc);
990
991 rtc->is_suspending = false;
992
993 return 0;
994 }
995
omap_rtc_runtime_suspend(struct device * dev)996 static int __maybe_unused omap_rtc_runtime_suspend(struct device *dev)
997 {
998 struct omap_rtc *rtc = dev_get_drvdata(dev);
999
1000 if (rtc->is_suspending && !rtc->has_ext_clk)
1001 return -EBUSY;
1002
1003 return 0;
1004 }
1005
1006 static const struct dev_pm_ops omap_rtc_pm_ops = {
1007 SET_SYSTEM_SLEEP_PM_OPS(omap_rtc_suspend, omap_rtc_resume)
1008 SET_RUNTIME_PM_OPS(omap_rtc_runtime_suspend, NULL, NULL)
1009 };
1010
omap_rtc_shutdown(struct platform_device * pdev)1011 static void omap_rtc_shutdown(struct platform_device *pdev)
1012 {
1013 struct omap_rtc *rtc = platform_get_drvdata(pdev);
1014 u8 mask;
1015
1016 /*
1017 * Keep the ALARM interrupt enabled to allow the system to power up on
1018 * alarm events.
1019 */
1020 rtc->type->unlock(rtc);
1021 mask = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
1022 mask &= OMAP_RTC_INTERRUPTS_IT_ALARM;
1023 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, mask);
1024 rtc->type->lock(rtc);
1025 }
1026
1027 static struct platform_driver omap_rtc_driver = {
1028 .probe = omap_rtc_probe,
1029 .remove = omap_rtc_remove,
1030 .shutdown = omap_rtc_shutdown,
1031 .driver = {
1032 .name = "omap_rtc",
1033 .pm = &omap_rtc_pm_ops,
1034 .of_match_table = omap_rtc_of_match,
1035 },
1036 .id_table = omap_rtc_id_table,
1037 };
1038
1039 module_platform_driver(omap_rtc_driver);
1040
1041 MODULE_ALIAS("platform:omap_rtc");
1042 MODULE_AUTHOR("George G. Davis (and others)");
1043 MODULE_LICENSE("GPL");
1044