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1/*
2 * drivers/rtc/rtc-pl031.c
3 *
4 * Real Time Clock interface for ARM AMBA PrimeCell 031 RTC
5 *
6 * Author: Deepak Saxena <dsaxena@plexity.net>
7 *
8 * Copyright 2006 (c) MontaVista Software, Inc.
9 *
10 * Author: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
11 * Copyright 2010 (c) ST-Ericsson AB
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
17 */
18#include <linux/module.h>
19#include <linux/rtc.h>
20#include <linux/init.h>
21#include <linux/interrupt.h>
22#include <linux/amba/bus.h>
23#include <linux/io.h>
24#include <linux/bcd.h>
25#include <linux/delay.h>
26#include <linux/pm_wakeirq.h>
27#include <linux/slab.h>
28
29/*
30 * Register definitions
31 */
32#define RTC_DR 0x00 /* Data read register */
33#define RTC_MR 0x04 /* Match register */
34#define RTC_LR 0x08 /* Data load register */
35#define RTC_CR 0x0c /* Control register */
36#define RTC_IMSC 0x10 /* Interrupt mask and set register */
37#define RTC_RIS 0x14 /* Raw interrupt status register */
38#define RTC_MIS 0x18 /* Masked interrupt status register */
39#define RTC_ICR 0x1c /* Interrupt clear register */
40/* ST variants have additional timer functionality */
41#define RTC_TDR 0x20 /* Timer data read register */
42#define RTC_TLR 0x24 /* Timer data load register */
43#define RTC_TCR 0x28 /* Timer control register */
44#define RTC_YDR 0x30 /* Year data read register */
45#define RTC_YMR 0x34 /* Year match register */
46#define RTC_YLR 0x38 /* Year data load register */
47
48#define RTC_CR_EN (1 << 0) /* counter enable bit */
49#define RTC_CR_CWEN (1 << 26) /* Clockwatch enable bit */
50
51#define RTC_TCR_EN (1 << 1) /* Periodic timer enable bit */
52
53/* Common bit definitions for Interrupt status and control registers */
54#define RTC_BIT_AI (1 << 0) /* Alarm interrupt bit */
55#define RTC_BIT_PI (1 << 1) /* Periodic interrupt bit. ST variants only. */
56
57/* Common bit definations for ST v2 for reading/writing time */
58#define RTC_SEC_SHIFT 0
59#define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
60#define RTC_MIN_SHIFT 6
61#define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
62#define RTC_HOUR_SHIFT 12
63#define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
64#define RTC_WDAY_SHIFT 17
65#define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
66#define RTC_MDAY_SHIFT 20
67#define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
68#define RTC_MON_SHIFT 25
69#define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */
70
71#define RTC_TIMER_FREQ 32768
72
73/**
74 * struct pl031_vendor_data - per-vendor variations
75 * @ops: the vendor-specific operations used on this silicon version
76 * @clockwatch: if this is an ST Microelectronics silicon version with a
77 * clockwatch function
78 * @st_weekday: if this is an ST Microelectronics silicon version that need
79 * the weekday fix
80 * @irqflags: special IRQ flags per variant
81 */
82struct pl031_vendor_data {
83 struct rtc_class_ops ops;
84 bool clockwatch;
85 bool st_weekday;
86 unsigned long irqflags;
87};
88
89struct pl031_local {
90 struct pl031_vendor_data *vendor;
91 struct rtc_device *rtc;
92 void __iomem *base;
93};
94
95static int pl031_alarm_irq_enable(struct device *dev,
96 unsigned int enabled)
97{
98 struct pl031_local *ldata = dev_get_drvdata(dev);
99 unsigned long imsc;
100
101 /* Clear any pending alarm interrupts. */
102 writel(RTC_BIT_AI, ldata->base + RTC_ICR);
103
104 imsc = readl(ldata->base + RTC_IMSC);
105
106 if (enabled == 1)
107 writel(imsc | RTC_BIT_AI, ldata->base + RTC_IMSC);
108 else
109 writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
110
111 return 0;
112}
113
114/*
115 * Convert Gregorian date to ST v2 RTC format.
116 */
117static int pl031_stv2_tm_to_time(struct device *dev,
118 struct rtc_time *tm, unsigned long *st_time,
119 unsigned long *bcd_year)
120{
121 int year = tm->tm_year + 1900;
122 int wday = tm->tm_wday;
123
124 /* wday masking is not working in hardware so wday must be valid */
125 if (wday < -1 || wday > 6) {
126 dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
127 return -EINVAL;
128 } else if (wday == -1) {
129 /* wday is not provided, calculate it here */
130 unsigned long time;
131 struct rtc_time calc_tm;
132
133 rtc_tm_to_time(tm, &time);
134 rtc_time_to_tm(time, &calc_tm);
135 wday = calc_tm.tm_wday;
136 }
137
138 *bcd_year = (bin2bcd(year % 100) | bin2bcd(year / 100) << 8);
139
140 *st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
141 | (tm->tm_mday << RTC_MDAY_SHIFT)
142 | ((wday + 1) << RTC_WDAY_SHIFT)
143 | (tm->tm_hour << RTC_HOUR_SHIFT)
144 | (tm->tm_min << RTC_MIN_SHIFT)
145 | (tm->tm_sec << RTC_SEC_SHIFT);
146
147 return 0;
148}
149
150/*
151 * Convert ST v2 RTC format to Gregorian date.
152 */
153static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
154 struct rtc_time *tm)
155{
156 tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
157 tm->tm_mon = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
158 tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
159 tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
160 tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
161 tm->tm_min = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
162 tm->tm_sec = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
163
164 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
165 tm->tm_year -= 1900;
166
167 return 0;
168}
169
170static int pl031_stv2_read_time(struct device *dev, struct rtc_time *tm)
171{
172 struct pl031_local *ldata = dev_get_drvdata(dev);
173
174 pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
175 readl(ldata->base + RTC_YDR), tm);
176
177 return 0;
178}
179
180static int pl031_stv2_set_time(struct device *dev, struct rtc_time *tm)
181{
182 unsigned long time;
183 unsigned long bcd_year;
184 struct pl031_local *ldata = dev_get_drvdata(dev);
185 int ret;
186
187 ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
188 if (ret == 0) {
189 writel(bcd_year, ldata->base + RTC_YLR);
190 writel(time, ldata->base + RTC_LR);
191 }
192
193 return ret;
194}
195
196static int pl031_stv2_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
197{
198 struct pl031_local *ldata = dev_get_drvdata(dev);
199 int ret;
200
201 ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
202 readl(ldata->base + RTC_YMR), &alarm->time);
203
204 alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
205 alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
206
207 return ret;
208}
209
210static int pl031_stv2_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
211{
212 struct pl031_local *ldata = dev_get_drvdata(dev);
213 unsigned long time;
214 unsigned long bcd_year;
215 int ret;
216
217 /* At the moment, we can only deal with non-wildcarded alarm times. */
218 ret = rtc_valid_tm(&alarm->time);
219 if (ret == 0) {
220 ret = pl031_stv2_tm_to_time(dev, &alarm->time,
221 &time, &bcd_year);
222 if (ret == 0) {
223 writel(bcd_year, ldata->base + RTC_YMR);
224 writel(time, ldata->base + RTC_MR);
225
226 pl031_alarm_irq_enable(dev, alarm->enabled);
227 }
228 }
229
230 return ret;
231}
232
233static irqreturn_t pl031_interrupt(int irq, void *dev_id)
234{
235 struct pl031_local *ldata = dev_id;
236 unsigned long rtcmis;
237 unsigned long events = 0;
238
239 rtcmis = readl(ldata->base + RTC_MIS);
240 if (rtcmis & RTC_BIT_AI) {
241 writel(RTC_BIT_AI, ldata->base + RTC_ICR);
242 events |= (RTC_AF | RTC_IRQF);
243 rtc_update_irq(ldata->rtc, 1, events);
244
245 return IRQ_HANDLED;
246 }
247
248 return IRQ_NONE;
249}
250
251static int pl031_read_time(struct device *dev, struct rtc_time *tm)
252{
253 struct pl031_local *ldata = dev_get_drvdata(dev);
254
255 rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);
256
257 return 0;
258}
259
260static int pl031_set_time(struct device *dev, struct rtc_time *tm)
261{
262 unsigned long time;
263 struct pl031_local *ldata = dev_get_drvdata(dev);
264 int ret;
265
266 ret = rtc_tm_to_time(tm, &time);
267
268 if (ret == 0)
269 writel(time, ldata->base + RTC_LR);
270
271 return ret;
272}
273
274static int pl031_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
275{
276 struct pl031_local *ldata = dev_get_drvdata(dev);
277
278 rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
279
280 alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
281 alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
282
283 return 0;
284}
285
286static int pl031_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
287{
288 struct pl031_local *ldata = dev_get_drvdata(dev);
289 unsigned long time;
290 int ret;
291
292 /* At the moment, we can only deal with non-wildcarded alarm times. */
293 ret = rtc_valid_tm(&alarm->time);
294 if (ret == 0) {
295 ret = rtc_tm_to_time(&alarm->time, &time);
296 if (ret == 0) {
297 writel(time, ldata->base + RTC_MR);
298 pl031_alarm_irq_enable(dev, alarm->enabled);
299 }
300 }
301
302 return ret;
303}
304
305static int pl031_remove(struct amba_device *adev)
306{
307 struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
308
309 dev_pm_clear_wake_irq(&adev->dev);
310 device_init_wakeup(&adev->dev, false);
311 free_irq(adev->irq[0], ldata);
312 rtc_device_unregister(ldata->rtc);
313 iounmap(ldata->base);
314 kfree(ldata);
315 amba_release_regions(adev);
316
317 return 0;
318}
319
320static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
321{
322 int ret;
323 struct pl031_local *ldata;
324 struct pl031_vendor_data *vendor = id->data;
325 struct rtc_class_ops *ops = &vendor->ops;
326 unsigned long time, data;
327
328 ret = amba_request_regions(adev, NULL);
329 if (ret)
330 goto err_req;
331
332 ldata = kzalloc(sizeof(struct pl031_local), GFP_KERNEL);
333 if (!ldata) {
334 ret = -ENOMEM;
335 goto out;
336 }
337 ldata->vendor = vendor;
338
339 ldata->base = ioremap(adev->res.start, resource_size(&adev->res));
340
341 if (!ldata->base) {
342 ret = -ENOMEM;
343 goto out_no_remap;
344 }
345
346 amba_set_drvdata(adev, ldata);
347
348 dev_dbg(&adev->dev, "designer ID = 0x%02x\n", amba_manf(adev));
349 dev_dbg(&adev->dev, "revision = 0x%01x\n", amba_rev(adev));
350
351 data = readl(ldata->base + RTC_CR);
352 /* Enable the clockwatch on ST Variants */
353 if (vendor->clockwatch)
354 data |= RTC_CR_CWEN;
355 else
356 data |= RTC_CR_EN;
357 writel(data, ldata->base + RTC_CR);
358
359 /*
360 * On ST PL031 variants, the RTC reset value does not provide correct
361 * weekday for 2000-01-01. Correct the erroneous sunday to saturday.
362 */
363 if (vendor->st_weekday) {
364 if (readl(ldata->base + RTC_YDR) == 0x2000) {
365 time = readl(ldata->base + RTC_DR);
366 if ((time &
367 (RTC_MON_MASK | RTC_MDAY_MASK | RTC_WDAY_MASK))
368 == 0x02120000) {
369 time = time | (0x7 << RTC_WDAY_SHIFT);
370 writel(0x2000, ldata->base + RTC_YLR);
371 writel(time, ldata->base + RTC_LR);
372 }
373 }
374 }
375
376 device_init_wakeup(&adev->dev, true);
377 ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
378 THIS_MODULE);
379 if (IS_ERR(ldata->rtc)) {
380 ret = PTR_ERR(ldata->rtc);
381 goto out_no_rtc;
382 }
383
384 if (request_irq(adev->irq[0], pl031_interrupt,
385 vendor->irqflags, "rtc-pl031", ldata)) {
386 ret = -EIO;
387 goto out_no_irq;
388 }
389 dev_pm_set_wake_irq(&adev->dev, adev->irq[0]);
390 return 0;
391
392out_no_irq:
393 rtc_device_unregister(ldata->rtc);
394out_no_rtc:
395 iounmap(ldata->base);
396out_no_remap:
397 kfree(ldata);
398out:
399 amba_release_regions(adev);
400err_req:
401
402 return ret;
403}
404
405/* Operations for the original ARM version */
406static struct pl031_vendor_data arm_pl031 = {
407 .ops = {
408 .read_time = pl031_read_time,
409 .set_time = pl031_set_time,
410 .read_alarm = pl031_read_alarm,
411 .set_alarm = pl031_set_alarm,
412 .alarm_irq_enable = pl031_alarm_irq_enable,
413 },
414};
415
416/* The First ST derivative */
417static struct pl031_vendor_data stv1_pl031 = {
418 .ops = {
419 .read_time = pl031_read_time,
420 .set_time = pl031_set_time,
421 .read_alarm = pl031_read_alarm,
422 .set_alarm = pl031_set_alarm,
423 .alarm_irq_enable = pl031_alarm_irq_enable,
424 },
425 .clockwatch = true,
426 .st_weekday = true,
427};
428
429/* And the second ST derivative */
430static struct pl031_vendor_data stv2_pl031 = {
431 .ops = {
432 .read_time = pl031_stv2_read_time,
433 .set_time = pl031_stv2_set_time,
434 .read_alarm = pl031_stv2_read_alarm,
435 .set_alarm = pl031_stv2_set_alarm,
436 .alarm_irq_enable = pl031_alarm_irq_enable,
437 },
438 .clockwatch = true,
439 .st_weekday = true,
440 /*
441 * This variant shares the IRQ with another block and must not
442 * suspend that IRQ line.
443 * TODO check if it shares with IRQF_NO_SUSPEND user, else we can
444 * remove IRQF_COND_SUSPEND
445 */
446 .irqflags = IRQF_SHARED | IRQF_COND_SUSPEND,
447};
448
449static struct amba_id pl031_ids[] = {
450 {
451 .id = 0x00041031,
452 .mask = 0x000fffff,
453 .data = &arm_pl031,
454 },
455 /* ST Micro variants */
456 {
457 .id = 0x00180031,
458 .mask = 0x00ffffff,
459 .data = &stv1_pl031,
460 },
461 {
462 .id = 0x00280031,
463 .mask = 0x00ffffff,
464 .data = &stv2_pl031,
465 },
466 {0, 0},
467};
468
469MODULE_DEVICE_TABLE(amba, pl031_ids);
470
471static struct amba_driver pl031_driver = {
472 .drv = {
473 .name = "rtc-pl031",
474 },
475 .id_table = pl031_ids,
476 .probe = pl031_probe,
477 .remove = pl031_remove,
478};
479
480module_amba_driver(pl031_driver);
481
482MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
483MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
484MODULE_LICENSE("GPL");
1/*
2 * drivers/rtc/rtc-pl031.c
3 *
4 * Real Time Clock interface for ARM AMBA PrimeCell 031 RTC
5 *
6 * Author: Deepak Saxena <dsaxena@plexity.net>
7 *
8 * Copyright 2006 (c) MontaVista Software, Inc.
9 *
10 * Author: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
11 * Copyright 2010 (c) ST-Ericsson AB
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
17 */
18#include <linux/module.h>
19#include <linux/rtc.h>
20#include <linux/init.h>
21#include <linux/interrupt.h>
22#include <linux/amba/bus.h>
23#include <linux/io.h>
24#include <linux/bcd.h>
25#include <linux/delay.h>
26#include <linux/slab.h>
27
28/*
29 * Register definitions
30 */
31#define RTC_DR 0x00 /* Data read register */
32#define RTC_MR 0x04 /* Match register */
33#define RTC_LR 0x08 /* Data load register */
34#define RTC_CR 0x0c /* Control register */
35#define RTC_IMSC 0x10 /* Interrupt mask and set register */
36#define RTC_RIS 0x14 /* Raw interrupt status register */
37#define RTC_MIS 0x18 /* Masked interrupt status register */
38#define RTC_ICR 0x1c /* Interrupt clear register */
39/* ST variants have additional timer functionality */
40#define RTC_TDR 0x20 /* Timer data read register */
41#define RTC_TLR 0x24 /* Timer data load register */
42#define RTC_TCR 0x28 /* Timer control register */
43#define RTC_YDR 0x30 /* Year data read register */
44#define RTC_YMR 0x34 /* Year match register */
45#define RTC_YLR 0x38 /* Year data load register */
46
47#define RTC_CR_EN (1 << 0) /* counter enable bit */
48#define RTC_CR_CWEN (1 << 26) /* Clockwatch enable bit */
49
50#define RTC_TCR_EN (1 << 1) /* Periodic timer enable bit */
51
52/* Common bit definitions for Interrupt status and control registers */
53#define RTC_BIT_AI (1 << 0) /* Alarm interrupt bit */
54#define RTC_BIT_PI (1 << 1) /* Periodic interrupt bit. ST variants only. */
55
56/* Common bit definations for ST v2 for reading/writing time */
57#define RTC_SEC_SHIFT 0
58#define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
59#define RTC_MIN_SHIFT 6
60#define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
61#define RTC_HOUR_SHIFT 12
62#define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
63#define RTC_WDAY_SHIFT 17
64#define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
65#define RTC_MDAY_SHIFT 20
66#define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
67#define RTC_MON_SHIFT 25
68#define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */
69
70#define RTC_TIMER_FREQ 32768
71
72/**
73 * struct pl031_vendor_data - per-vendor variations
74 * @ops: the vendor-specific operations used on this silicon version
75 * @clockwatch: if this is an ST Microelectronics silicon version with a
76 * clockwatch function
77 * @st_weekday: if this is an ST Microelectronics silicon version that need
78 * the weekday fix
79 * @irqflags: special IRQ flags per variant
80 */
81struct pl031_vendor_data {
82 struct rtc_class_ops ops;
83 bool clockwatch;
84 bool st_weekday;
85 unsigned long irqflags;
86};
87
88struct pl031_local {
89 struct pl031_vendor_data *vendor;
90 struct rtc_device *rtc;
91 void __iomem *base;
92};
93
94static int pl031_alarm_irq_enable(struct device *dev,
95 unsigned int enabled)
96{
97 struct pl031_local *ldata = dev_get_drvdata(dev);
98 unsigned long imsc;
99
100 /* Clear any pending alarm interrupts. */
101 writel(RTC_BIT_AI, ldata->base + RTC_ICR);
102
103 imsc = readl(ldata->base + RTC_IMSC);
104
105 if (enabled == 1)
106 writel(imsc | RTC_BIT_AI, ldata->base + RTC_IMSC);
107 else
108 writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
109
110 return 0;
111}
112
113/*
114 * Convert Gregorian date to ST v2 RTC format.
115 */
116static int pl031_stv2_tm_to_time(struct device *dev,
117 struct rtc_time *tm, unsigned long *st_time,
118 unsigned long *bcd_year)
119{
120 int year = tm->tm_year + 1900;
121 int wday = tm->tm_wday;
122
123 /* wday masking is not working in hardware so wday must be valid */
124 if (wday < -1 || wday > 6) {
125 dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
126 return -EINVAL;
127 } else if (wday == -1) {
128 /* wday is not provided, calculate it here */
129 unsigned long time;
130 struct rtc_time calc_tm;
131
132 rtc_tm_to_time(tm, &time);
133 rtc_time_to_tm(time, &calc_tm);
134 wday = calc_tm.tm_wday;
135 }
136
137 *bcd_year = (bin2bcd(year % 100) | bin2bcd(year / 100) << 8);
138
139 *st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
140 | (tm->tm_mday << RTC_MDAY_SHIFT)
141 | ((wday + 1) << RTC_WDAY_SHIFT)
142 | (tm->tm_hour << RTC_HOUR_SHIFT)
143 | (tm->tm_min << RTC_MIN_SHIFT)
144 | (tm->tm_sec << RTC_SEC_SHIFT);
145
146 return 0;
147}
148
149/*
150 * Convert ST v2 RTC format to Gregorian date.
151 */
152static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
153 struct rtc_time *tm)
154{
155 tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
156 tm->tm_mon = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
157 tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
158 tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
159 tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
160 tm->tm_min = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
161 tm->tm_sec = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
162
163 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
164 tm->tm_year -= 1900;
165
166 return 0;
167}
168
169static int pl031_stv2_read_time(struct device *dev, struct rtc_time *tm)
170{
171 struct pl031_local *ldata = dev_get_drvdata(dev);
172
173 pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
174 readl(ldata->base + RTC_YDR), tm);
175
176 return 0;
177}
178
179static int pl031_stv2_set_time(struct device *dev, struct rtc_time *tm)
180{
181 unsigned long time;
182 unsigned long bcd_year;
183 struct pl031_local *ldata = dev_get_drvdata(dev);
184 int ret;
185
186 ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
187 if (ret == 0) {
188 writel(bcd_year, ldata->base + RTC_YLR);
189 writel(time, ldata->base + RTC_LR);
190 }
191
192 return ret;
193}
194
195static int pl031_stv2_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
196{
197 struct pl031_local *ldata = dev_get_drvdata(dev);
198 int ret;
199
200 ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
201 readl(ldata->base + RTC_YMR), &alarm->time);
202
203 alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
204 alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
205
206 return ret;
207}
208
209static int pl031_stv2_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
210{
211 struct pl031_local *ldata = dev_get_drvdata(dev);
212 unsigned long time;
213 unsigned long bcd_year;
214 int ret;
215
216 /* At the moment, we can only deal with non-wildcarded alarm times. */
217 ret = rtc_valid_tm(&alarm->time);
218 if (ret == 0) {
219 ret = pl031_stv2_tm_to_time(dev, &alarm->time,
220 &time, &bcd_year);
221 if (ret == 0) {
222 writel(bcd_year, ldata->base + RTC_YMR);
223 writel(time, ldata->base + RTC_MR);
224
225 pl031_alarm_irq_enable(dev, alarm->enabled);
226 }
227 }
228
229 return ret;
230}
231
232static irqreturn_t pl031_interrupt(int irq, void *dev_id)
233{
234 struct pl031_local *ldata = dev_id;
235 unsigned long rtcmis;
236 unsigned long events = 0;
237
238 rtcmis = readl(ldata->base + RTC_MIS);
239 if (rtcmis & RTC_BIT_AI) {
240 writel(RTC_BIT_AI, ldata->base + RTC_ICR);
241 events |= (RTC_AF | RTC_IRQF);
242 rtc_update_irq(ldata->rtc, 1, events);
243
244 return IRQ_HANDLED;
245 }
246
247 return IRQ_NONE;
248}
249
250static int pl031_read_time(struct device *dev, struct rtc_time *tm)
251{
252 struct pl031_local *ldata = dev_get_drvdata(dev);
253
254 rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);
255
256 return 0;
257}
258
259static int pl031_set_time(struct device *dev, struct rtc_time *tm)
260{
261 unsigned long time;
262 struct pl031_local *ldata = dev_get_drvdata(dev);
263 int ret;
264
265 ret = rtc_tm_to_time(tm, &time);
266
267 if (ret == 0)
268 writel(time, ldata->base + RTC_LR);
269
270 return ret;
271}
272
273static int pl031_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
274{
275 struct pl031_local *ldata = dev_get_drvdata(dev);
276
277 rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
278
279 alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
280 alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
281
282 return 0;
283}
284
285static int pl031_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
286{
287 struct pl031_local *ldata = dev_get_drvdata(dev);
288 unsigned long time;
289 int ret;
290
291 /* At the moment, we can only deal with non-wildcarded alarm times. */
292 ret = rtc_valid_tm(&alarm->time);
293 if (ret == 0) {
294 ret = rtc_tm_to_time(&alarm->time, &time);
295 if (ret == 0) {
296 writel(time, ldata->base + RTC_MR);
297 pl031_alarm_irq_enable(dev, alarm->enabled);
298 }
299 }
300
301 return ret;
302}
303
304static int pl031_remove(struct amba_device *adev)
305{
306 struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
307
308 free_irq(adev->irq[0], ldata);
309 rtc_device_unregister(ldata->rtc);
310 iounmap(ldata->base);
311 kfree(ldata);
312 amba_release_regions(adev);
313
314 return 0;
315}
316
317static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
318{
319 int ret;
320 struct pl031_local *ldata;
321 struct pl031_vendor_data *vendor = id->data;
322 struct rtc_class_ops *ops = &vendor->ops;
323 unsigned long time, data;
324
325 ret = amba_request_regions(adev, NULL);
326 if (ret)
327 goto err_req;
328
329 ldata = kzalloc(sizeof(struct pl031_local), GFP_KERNEL);
330 if (!ldata) {
331 ret = -ENOMEM;
332 goto out;
333 }
334 ldata->vendor = vendor;
335
336 ldata->base = ioremap(adev->res.start, resource_size(&adev->res));
337
338 if (!ldata->base) {
339 ret = -ENOMEM;
340 goto out_no_remap;
341 }
342
343 amba_set_drvdata(adev, ldata);
344
345 dev_dbg(&adev->dev, "designer ID = 0x%02x\n", amba_manf(adev));
346 dev_dbg(&adev->dev, "revision = 0x%01x\n", amba_rev(adev));
347
348 data = readl(ldata->base + RTC_CR);
349 /* Enable the clockwatch on ST Variants */
350 if (vendor->clockwatch)
351 data |= RTC_CR_CWEN;
352 else
353 data |= RTC_CR_EN;
354 writel(data, ldata->base + RTC_CR);
355
356 /*
357 * On ST PL031 variants, the RTC reset value does not provide correct
358 * weekday for 2000-01-01. Correct the erroneous sunday to saturday.
359 */
360 if (vendor->st_weekday) {
361 if (readl(ldata->base + RTC_YDR) == 0x2000) {
362 time = readl(ldata->base + RTC_DR);
363 if ((time &
364 (RTC_MON_MASK | RTC_MDAY_MASK | RTC_WDAY_MASK))
365 == 0x02120000) {
366 time = time | (0x7 << RTC_WDAY_SHIFT);
367 writel(0x2000, ldata->base + RTC_YLR);
368 writel(time, ldata->base + RTC_LR);
369 }
370 }
371 }
372
373 device_init_wakeup(&adev->dev, 1);
374 ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
375 THIS_MODULE);
376 if (IS_ERR(ldata->rtc)) {
377 ret = PTR_ERR(ldata->rtc);
378 goto out_no_rtc;
379 }
380
381 if (request_irq(adev->irq[0], pl031_interrupt,
382 vendor->irqflags, "rtc-pl031", ldata)) {
383 ret = -EIO;
384 goto out_no_irq;
385 }
386
387 return 0;
388
389out_no_irq:
390 rtc_device_unregister(ldata->rtc);
391out_no_rtc:
392 iounmap(ldata->base);
393out_no_remap:
394 kfree(ldata);
395out:
396 amba_release_regions(adev);
397err_req:
398
399 return ret;
400}
401
402/* Operations for the original ARM version */
403static struct pl031_vendor_data arm_pl031 = {
404 .ops = {
405 .read_time = pl031_read_time,
406 .set_time = pl031_set_time,
407 .read_alarm = pl031_read_alarm,
408 .set_alarm = pl031_set_alarm,
409 .alarm_irq_enable = pl031_alarm_irq_enable,
410 },
411 .irqflags = IRQF_NO_SUSPEND,
412};
413
414/* The First ST derivative */
415static struct pl031_vendor_data stv1_pl031 = {
416 .ops = {
417 .read_time = pl031_read_time,
418 .set_time = pl031_set_time,
419 .read_alarm = pl031_read_alarm,
420 .set_alarm = pl031_set_alarm,
421 .alarm_irq_enable = pl031_alarm_irq_enable,
422 },
423 .clockwatch = true,
424 .st_weekday = true,
425 .irqflags = IRQF_NO_SUSPEND,
426};
427
428/* And the second ST derivative */
429static struct pl031_vendor_data stv2_pl031 = {
430 .ops = {
431 .read_time = pl031_stv2_read_time,
432 .set_time = pl031_stv2_set_time,
433 .read_alarm = pl031_stv2_read_alarm,
434 .set_alarm = pl031_stv2_set_alarm,
435 .alarm_irq_enable = pl031_alarm_irq_enable,
436 },
437 .clockwatch = true,
438 .st_weekday = true,
439 /*
440 * This variant shares the IRQ with another block and must not
441 * suspend that IRQ line.
442 */
443 .irqflags = IRQF_SHARED | IRQF_NO_SUSPEND,
444};
445
446static struct amba_id pl031_ids[] = {
447 {
448 .id = 0x00041031,
449 .mask = 0x000fffff,
450 .data = &arm_pl031,
451 },
452 /* ST Micro variants */
453 {
454 .id = 0x00180031,
455 .mask = 0x00ffffff,
456 .data = &stv1_pl031,
457 },
458 {
459 .id = 0x00280031,
460 .mask = 0x00ffffff,
461 .data = &stv2_pl031,
462 },
463 {0, 0},
464};
465
466MODULE_DEVICE_TABLE(amba, pl031_ids);
467
468static struct amba_driver pl031_driver = {
469 .drv = {
470 .name = "rtc-pl031",
471 },
472 .id_table = pl031_ids,
473 .probe = pl031_probe,
474 .remove = pl031_remove,
475};
476
477module_amba_driver(pl031_driver);
478
479MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net");
480MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
481MODULE_LICENSE("GPL");