mfd: kempld-core: Constify variables that point to const structure
[linux-2.6-block.git] / drivers / rtc / rtc-omap.c
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  * Notes:
425  * The two-second alarm offset is the shortest offset possible as the alarm
426  * registers must be set before the next timer update and the offset
427  * calculation is too heavy for everything to be done within a single access
428  * period (~15 us).
429  *
430  * Called with local interrupts disabled.
431  */
432 static void omap_rtc_power_off(void)
433 {
434         struct omap_rtc *rtc = omap_rtc_power_off_rtc;
435         struct rtc_time tm;
436         unsigned long now;
437         u32 val;
438
439         rtc->type->unlock(rtc);
440         /* enable pmic_power_en control */
441         val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
442         rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
443
444         /* set alarm two seconds from now */
445         omap_rtc_read_time_raw(rtc, &tm);
446         bcd2tm(&tm);
447         rtc_tm_to_time(&tm, &now);
448         rtc_time_to_tm(now + 2, &tm);
449
450         if (tm2bcd(&tm) < 0) {
451                 dev_err(&rtc->rtc->dev, "power off failed\n");
452                 return;
453         }
454
455         rtc_wait_not_busy(rtc);
456
457         rtc_write(rtc, OMAP_RTC_ALARM2_SECONDS_REG, tm.tm_sec);
458         rtc_write(rtc, OMAP_RTC_ALARM2_MINUTES_REG, tm.tm_min);
459         rtc_write(rtc, OMAP_RTC_ALARM2_HOURS_REG, tm.tm_hour);
460         rtc_write(rtc, OMAP_RTC_ALARM2_DAYS_REG, tm.tm_mday);
461         rtc_write(rtc, OMAP_RTC_ALARM2_MONTHS_REG, tm.tm_mon);
462         rtc_write(rtc, OMAP_RTC_ALARM2_YEARS_REG, tm.tm_year);
463
464         /*
465          * enable ALARM2 interrupt
466          *
467          * NOTE: this fails on AM3352 if rtc_write (writeb) is used
468          */
469         val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
470         rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
471                         val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
472         rtc->type->lock(rtc);
473
474         /*
475          * Wait for alarm to trigger (within two seconds) and external PMIC to
476          * power off the system. Add a 500 ms margin for external latencies
477          * (e.g. debounce circuits).
478          */
479         mdelay(2500);
480 }
481
482 static const struct rtc_class_ops omap_rtc_ops = {
483         .read_time      = omap_rtc_read_time,
484         .set_time       = omap_rtc_set_time,
485         .read_alarm     = omap_rtc_read_alarm,
486         .set_alarm      = omap_rtc_set_alarm,
487         .alarm_irq_enable = omap_rtc_alarm_irq_enable,
488 };
489
490 static const struct omap_rtc_device_type omap_rtc_default_type = {
491         .has_power_up_reset = true,
492         .lock           = default_rtc_lock,
493         .unlock         = default_rtc_unlock,
494 };
495
496 static const struct omap_rtc_device_type omap_rtc_am3352_type = {
497         .has_32kclk_en  = true,
498         .has_irqwakeen  = true,
499         .has_pmic_mode  = true,
500         .lock           = am3352_rtc_lock,
501         .unlock         = am3352_rtc_unlock,
502 };
503
504 static const struct omap_rtc_device_type omap_rtc_da830_type = {
505         .lock           = am3352_rtc_lock,
506         .unlock         = am3352_rtc_unlock,
507 };
508
509 static const struct platform_device_id omap_rtc_id_table[] = {
510         {
511                 .name   = "omap_rtc",
512                 .driver_data = (kernel_ulong_t)&omap_rtc_default_type,
513         }, {
514                 .name   = "am3352-rtc",
515                 .driver_data = (kernel_ulong_t)&omap_rtc_am3352_type,
516         }, {
517                 .name   = "da830-rtc",
518                 .driver_data = (kernel_ulong_t)&omap_rtc_da830_type,
519         }, {
520                 /* sentinel */
521         }
522 };
523 MODULE_DEVICE_TABLE(platform, omap_rtc_id_table);
524
525 static const struct of_device_id omap_rtc_of_match[] = {
526         {
527                 .compatible     = "ti,am3352-rtc",
528                 .data           = &omap_rtc_am3352_type,
529         }, {
530                 .compatible     = "ti,da830-rtc",
531                 .data           = &omap_rtc_da830_type,
532         }, {
533                 /* sentinel */
534         }
535 };
536 MODULE_DEVICE_TABLE(of, omap_rtc_of_match);
537
538 static const struct pinctrl_pin_desc rtc_pins_desc[] = {
539         PINCTRL_PIN(0, "ext_wakeup0"),
540         PINCTRL_PIN(1, "ext_wakeup1"),
541         PINCTRL_PIN(2, "ext_wakeup2"),
542         PINCTRL_PIN(3, "ext_wakeup3"),
543 };
544
545 static int rtc_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
546 {
547         return 0;
548 }
549
550 static const char *rtc_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
551                                         unsigned int group)
552 {
553         return NULL;
554 }
555
556 static const struct pinctrl_ops rtc_pinctrl_ops = {
557         .get_groups_count = rtc_pinctrl_get_groups_count,
558         .get_group_name = rtc_pinctrl_get_group_name,
559         .dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
560         .dt_free_map = pinconf_generic_dt_free_map,
561 };
562
563 enum rtc_pin_config_param {
564         PIN_CONFIG_ACTIVE_HIGH = PIN_CONFIG_END + 1,
565 };
566
567 static const struct pinconf_generic_params rtc_params[] = {
568         {"ti,active-high", PIN_CONFIG_ACTIVE_HIGH, 0},
569 };
570
571 #ifdef CONFIG_DEBUG_FS
572 static const struct pin_config_item rtc_conf_items[ARRAY_SIZE(rtc_params)] = {
573         PCONFDUMP(PIN_CONFIG_ACTIVE_HIGH, "input active high", NULL, false),
574 };
575 #endif
576
577 static int rtc_pinconf_get(struct pinctrl_dev *pctldev,
578                         unsigned int pin, unsigned long *config)
579 {
580         struct omap_rtc *rtc = pinctrl_dev_get_drvdata(pctldev);
581         unsigned int param = pinconf_to_config_param(*config);
582         u32 val;
583         u16 arg = 0;
584
585         rtc->type->unlock(rtc);
586         val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
587         rtc->type->lock(rtc);
588
589         switch (param) {
590         case PIN_CONFIG_INPUT_ENABLE:
591                 if (!(val & OMAP_RTC_PMIC_EXT_WKUP_EN(pin)))
592                         return -EINVAL;
593                 break;
594         case PIN_CONFIG_ACTIVE_HIGH:
595                 if (val & OMAP_RTC_PMIC_EXT_WKUP_POL(pin))
596                         return -EINVAL;
597                 break;
598         default:
599                 return -ENOTSUPP;
600         };
601
602         *config = pinconf_to_config_packed(param, arg);
603
604         return 0;
605 }
606
607 static int rtc_pinconf_set(struct pinctrl_dev *pctldev,
608                         unsigned int pin, unsigned long *configs,
609                         unsigned int num_configs)
610 {
611         struct omap_rtc *rtc = pinctrl_dev_get_drvdata(pctldev);
612         u32 val;
613         unsigned int param;
614         u32 param_val;
615         int i;
616
617         rtc->type->unlock(rtc);
618         val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
619         rtc->type->lock(rtc);
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_property_read_bool(pdev->dev.of_node,
728                                                 "system-power-controller");
729         } else {
730                 id_entry = platform_get_device_id(pdev);
731                 rtc->type = (void *)id_entry->driver_data;
732         }
733
734         rtc->irq_timer = platform_get_irq(pdev, 0);
735         if (rtc->irq_timer <= 0)
736                 return -ENOENT;
737
738         rtc->irq_alarm = platform_get_irq(pdev, 1);
739         if (rtc->irq_alarm <= 0)
740                 return -ENOENT;
741
742         rtc->clk = devm_clk_get(&pdev->dev, "ext-clk");
743         if (!IS_ERR(rtc->clk))
744                 rtc->has_ext_clk = true;
745         else
746                 rtc->clk = devm_clk_get(&pdev->dev, "int-clk");
747
748         if (!IS_ERR(rtc->clk))
749                 clk_prepare_enable(rtc->clk);
750
751         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
752         rtc->base = devm_ioremap_resource(&pdev->dev, res);
753         if (IS_ERR(rtc->base)) {
754                 clk_disable_unprepare(rtc->clk);
755                 return PTR_ERR(rtc->base);
756         }
757
758         platform_set_drvdata(pdev, rtc);
759
760         /* Enable the clock/module so that we can access the registers */
761         pm_runtime_enable(&pdev->dev);
762         pm_runtime_get_sync(&pdev->dev);
763
764         rtc->type->unlock(rtc);
765
766         /*
767          * disable interrupts
768          *
769          * NOTE: ALARM2 is not cleared on AM3352 if rtc_write (writeb) is used
770          */
771         rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
772
773         /* enable RTC functional clock */
774         if (rtc->type->has_32kclk_en) {
775                 reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
776                 rtc_writel(rtc, OMAP_RTC_OSC_REG,
777                                 reg | OMAP_RTC_OSC_32KCLK_EN);
778         }
779
780         /* clear old status */
781         reg = rtc_read(rtc, OMAP_RTC_STATUS_REG);
782
783         mask = OMAP_RTC_STATUS_ALARM;
784
785         if (rtc->type->has_pmic_mode)
786                 mask |= OMAP_RTC_STATUS_ALARM2;
787
788         if (rtc->type->has_power_up_reset) {
789                 mask |= OMAP_RTC_STATUS_POWER_UP;
790                 if (reg & OMAP_RTC_STATUS_POWER_UP)
791                         dev_info(&pdev->dev, "RTC power up reset detected\n");
792         }
793
794         if (reg & mask)
795                 rtc_write(rtc, OMAP_RTC_STATUS_REG, reg & mask);
796
797         /* On boards with split power, RTC_ON_NOFF won't reset the RTC */
798         reg = rtc_read(rtc, OMAP_RTC_CTRL_REG);
799         if (reg & OMAP_RTC_CTRL_STOP)
800                 dev_info(&pdev->dev, "already running\n");
801
802         /* force to 24 hour mode */
803         new_ctrl = reg & (OMAP_RTC_CTRL_SPLIT | OMAP_RTC_CTRL_AUTO_COMP);
804         new_ctrl |= OMAP_RTC_CTRL_STOP;
805
806         /*
807          * BOARD-SPECIFIC CUSTOMIZATION CAN GO HERE:
808          *
809          *  - Device wake-up capability setting should come through chip
810          *    init logic. OMAP1 boards should initialize the "wakeup capable"
811          *    flag in the platform device if the board is wired right for
812          *    being woken up by RTC alarm. For OMAP-L138, this capability
813          *    is built into the SoC by the "Deep Sleep" capability.
814          *
815          *  - Boards wired so RTC_ON_nOFF is used as the reset signal,
816          *    rather than nPWRON_RESET, should forcibly enable split
817          *    power mode.  (Some chip errata report that RTC_CTRL_SPLIT
818          *    is write-only, and always reads as zero...)
819          */
820
821         if (new_ctrl & OMAP_RTC_CTRL_SPLIT)
822                 dev_info(&pdev->dev, "split power mode\n");
823
824         if (reg != new_ctrl)
825                 rtc_write(rtc, OMAP_RTC_CTRL_REG, new_ctrl);
826
827         /*
828          * If we have the external clock then switch to it so we can keep
829          * ticking across suspend.
830          */
831         if (rtc->has_ext_clk) {
832                 reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
833                 reg &= ~OMAP_RTC_OSC_OSC32K_GZ_DISABLE;
834                 reg |= OMAP_RTC_OSC_32KCLK_EN | OMAP_RTC_OSC_SEL_32KCLK_SRC;
835                 rtc_writel(rtc, OMAP_RTC_OSC_REG, reg);
836         }
837
838         rtc->type->lock(rtc);
839
840         device_init_wakeup(&pdev->dev, true);
841
842         rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
843         if (IS_ERR(rtc->rtc)) {
844                 ret = PTR_ERR(rtc->rtc);
845                 goto err;
846         }
847
848         rtc->rtc->ops = &omap_rtc_ops;
849         omap_rtc_nvmem_config.priv = rtc;
850
851         /* handle periodic and alarm irqs */
852         ret = devm_request_irq(&pdev->dev, rtc->irq_timer, rtc_irq, 0,
853                         dev_name(&rtc->rtc->dev), rtc);
854         if (ret)
855                 goto err;
856
857         if (rtc->irq_timer != rtc->irq_alarm) {
858                 ret = devm_request_irq(&pdev->dev, rtc->irq_alarm, rtc_irq, 0,
859                                 dev_name(&rtc->rtc->dev), rtc);
860                 if (ret)
861                         goto err;
862         }
863
864         if (rtc->is_pmic_controller) {
865                 if (!pm_power_off) {
866                         omap_rtc_power_off_rtc = rtc;
867                         pm_power_off = omap_rtc_power_off;
868                 }
869         }
870
871         /* Support ext_wakeup pinconf */
872         rtc_pinctrl_desc.name = dev_name(&pdev->dev);
873
874         rtc->pctldev = pinctrl_register(&rtc_pinctrl_desc, &pdev->dev, rtc);
875         if (IS_ERR(rtc->pctldev)) {
876                 dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
877                 ret = PTR_ERR(rtc->pctldev);
878                 goto err;
879         }
880
881         ret = rtc_register_device(rtc->rtc);
882         if (ret)
883                 goto err;
884
885         rtc_nvmem_register(rtc->rtc, &omap_rtc_nvmem_config);
886
887         return 0;
888
889 err:
890         clk_disable_unprepare(rtc->clk);
891         device_init_wakeup(&pdev->dev, false);
892         rtc->type->lock(rtc);
893         pm_runtime_put_sync(&pdev->dev);
894         pm_runtime_disable(&pdev->dev);
895
896         return ret;
897 }
898
899 static int omap_rtc_remove(struct platform_device *pdev)
900 {
901         struct omap_rtc *rtc = platform_get_drvdata(pdev);
902         u8 reg;
903
904         if (pm_power_off == omap_rtc_power_off &&
905                         omap_rtc_power_off_rtc == rtc) {
906                 pm_power_off = NULL;
907                 omap_rtc_power_off_rtc = NULL;
908         }
909
910         device_init_wakeup(&pdev->dev, 0);
911
912         if (!IS_ERR(rtc->clk))
913                 clk_disable_unprepare(rtc->clk);
914
915         rtc->type->unlock(rtc);
916         /* leave rtc running, but disable irqs */
917         rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
918
919         if (rtc->has_ext_clk) {
920                 reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
921                 reg &= ~OMAP_RTC_OSC_SEL_32KCLK_SRC;
922                 rtc_write(rtc, OMAP_RTC_OSC_REG, reg);
923         }
924
925         rtc->type->lock(rtc);
926
927         /* Disable the clock/module */
928         pm_runtime_put_sync(&pdev->dev);
929         pm_runtime_disable(&pdev->dev);
930
931         /* Remove ext_wakeup pinconf */
932         pinctrl_unregister(rtc->pctldev);
933
934         return 0;
935 }
936
937 static int __maybe_unused omap_rtc_suspend(struct device *dev)
938 {
939         struct omap_rtc *rtc = dev_get_drvdata(dev);
940
941         rtc->interrupts_reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
942
943         rtc->type->unlock(rtc);
944         /*
945          * FIXME: the RTC alarm is not currently acting as a wakeup event
946          * source on some platforms, and in fact this enable() call is just
947          * saving a flag that's never used...
948          */
949         if (device_may_wakeup(dev))
950                 enable_irq_wake(rtc->irq_alarm);
951         else
952                 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
953         rtc->type->lock(rtc);
954
955         rtc->is_suspending = true;
956
957         return 0;
958 }
959
960 static int __maybe_unused omap_rtc_resume(struct device *dev)
961 {
962         struct omap_rtc *rtc = dev_get_drvdata(dev);
963
964         rtc->type->unlock(rtc);
965         if (device_may_wakeup(dev))
966                 disable_irq_wake(rtc->irq_alarm);
967         else
968                 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, rtc->interrupts_reg);
969         rtc->type->lock(rtc);
970
971         rtc->is_suspending = false;
972
973         return 0;
974 }
975
976 static int __maybe_unused omap_rtc_runtime_suspend(struct device *dev)
977 {
978         struct omap_rtc *rtc = dev_get_drvdata(dev);
979
980         if (rtc->is_suspending && !rtc->has_ext_clk)
981                 return -EBUSY;
982
983         return 0;
984 }
985
986 static const struct dev_pm_ops omap_rtc_pm_ops = {
987         SET_SYSTEM_SLEEP_PM_OPS(omap_rtc_suspend, omap_rtc_resume)
988         SET_RUNTIME_PM_OPS(omap_rtc_runtime_suspend, NULL, NULL)
989 };
990
991 static void omap_rtc_shutdown(struct platform_device *pdev)
992 {
993         struct omap_rtc *rtc = platform_get_drvdata(pdev);
994         u8 mask;
995
996         /*
997          * Keep the ALARM interrupt enabled to allow the system to power up on
998          * alarm events.
999          */
1000         rtc->type->unlock(rtc);
1001         mask = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
1002         mask &= OMAP_RTC_INTERRUPTS_IT_ALARM;
1003         rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, mask);
1004         rtc->type->lock(rtc);
1005 }
1006
1007 static struct platform_driver omap_rtc_driver = {
1008         .probe          = omap_rtc_probe,
1009         .remove         = omap_rtc_remove,
1010         .shutdown       = omap_rtc_shutdown,
1011         .driver         = {
1012                 .name   = "omap_rtc",
1013                 .pm     = &omap_rtc_pm_ops,
1014                 .of_match_table = omap_rtc_of_match,
1015         },
1016         .id_table       = omap_rtc_id_table,
1017 };
1018
1019 module_platform_driver(omap_rtc_driver);
1020
1021 MODULE_ALIAS("platform:omap_rtc");
1022 MODULE_AUTHOR("George G. Davis (and others)");
1023 MODULE_LICENSE("GPL");