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cgroup: net_prio: Mark local used function static
[linux-2.6/libata-dev.git] / drivers / rtc / rtc-pl031.c
blob08378e3cc21cf8209796d50876ee64ae5c0a4aaa
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_CWEN (1 << 26) /* Clockwatch enable bit */
48
49 #define RTC_TCR_EN (1 << 1) /* Periodic timer enable bit */
50
51 /* Common bit definitions for Interrupt status and control registers */
52 #define RTC_BIT_AI (1 << 0) /* Alarm interrupt bit */
53 #define RTC_BIT_PI (1 << 1) /* Periodic interrupt bit. ST variants only. */
54
55 /* Common bit definations for ST v2 for reading/writing time */
56 #define RTC_SEC_SHIFT 0
57 #define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
58 #define RTC_MIN_SHIFT 6
59 #define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
60 #define RTC_HOUR_SHIFT 12
61 #define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
62 #define RTC_WDAY_SHIFT 17
63 #define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
64 #define RTC_MDAY_SHIFT 20
65 #define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
66 #define RTC_MON_SHIFT 25
67 #define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */
68
69 #define RTC_TIMER_FREQ 32768
70
71 /**
72 * struct pl031_vendor_data - per-vendor variations
73 * @ops: the vendor-specific operations used on this silicon version
74 * @clockwatch: if this is an ST Microelectronics silicon version with a
75 * clockwatch function
76 * @st_weekday: if this is an ST Microelectronics silicon version that need
77 * the weekday fix
78 * @irqflags: special IRQ flags per variant
79 */
80 struct pl031_vendor_data {
81 struct rtc_class_ops ops;
82 bool clockwatch;
83 bool st_weekday;
84 unsigned long irqflags;
85 };
86
87 struct pl031_local {
88 struct pl031_vendor_data *vendor;
89 struct rtc_device *rtc;
90 void __iomem *base;
91 };
92
93 static int pl031_alarm_irq_enable(struct device *dev,
94 unsigned int enabled)
95 {
96 struct pl031_local *ldata = dev_get_drvdata(dev);
97 unsigned long imsc;
98
99 /* Clear any pending alarm interrupts. */
100 writel(RTC_BIT_AI, ldata->base + RTC_ICR);
101
102 imsc = readl(ldata->base + RTC_IMSC);
103
104 if (enabled == 1)
105 writel(imsc | RTC_BIT_AI, ldata->base + RTC_IMSC);
106 else
107 writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
108
109 return 0;
110 }
111
112 /*
113 * Convert Gregorian date to ST v2 RTC format.
114 */
115 static int pl031_stv2_tm_to_time(struct device *dev,
116 struct rtc_time *tm, unsigned long *st_time,
117 unsigned long *bcd_year)
118 {
119 int year = tm->tm_year + 1900;
120 int wday = tm->tm_wday;
121
122 /* wday masking is not working in hardware so wday must be valid */
123 if (wday < -1 || wday > 6) {
124 dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
125 return -EINVAL;
126 } else if (wday == -1) {
127 /* wday is not provided, calculate it here */
128 unsigned long time;
129 struct rtc_time calc_tm;
130
131 rtc_tm_to_time(tm, &time);
132 rtc_time_to_tm(time, &calc_tm);
133 wday = calc_tm.tm_wday;
134 }
135
136 *bcd_year = (bin2bcd(year % 100) | bin2bcd(year / 100) << 8);
137
138 *st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
139 | (tm->tm_mday << RTC_MDAY_SHIFT)
140 | ((wday + 1) << RTC_WDAY_SHIFT)
141 | (tm->tm_hour << RTC_HOUR_SHIFT)
142 | (tm->tm_min << RTC_MIN_SHIFT)
143 | (tm->tm_sec << RTC_SEC_SHIFT);
144
145 return 0;
146 }
147
148 /*
149 * Convert ST v2 RTC format to Gregorian date.
150 */
151 static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
152 struct rtc_time *tm)
153 {
154 tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
155 tm->tm_mon = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
156 tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
157 tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
158 tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
159 tm->tm_min = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
160 tm->tm_sec = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
161
162 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
163 tm->tm_year -= 1900;
164
165 return 0;
166 }
167
168 static int pl031_stv2_read_time(struct device *dev, struct rtc_time *tm)
169 {
170 struct pl031_local *ldata = dev_get_drvdata(dev);
171
172 pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
173 readl(ldata->base + RTC_YDR), tm);
174
175 return 0;
176 }
177
178 static int pl031_stv2_set_time(struct device *dev, struct rtc_time *tm)
179 {
180 unsigned long time;
181 unsigned long bcd_year;
182 struct pl031_local *ldata = dev_get_drvdata(dev);
183 int ret;
184
185 ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
186 if (ret == 0) {
187 writel(bcd_year, ldata->base + RTC_YLR);
188 writel(time, ldata->base + RTC_LR);
189 }
190
191 return ret;
192 }
193
194 static int pl031_stv2_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
195 {
196 struct pl031_local *ldata = dev_get_drvdata(dev);
197 int ret;
198
199 ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
200 readl(ldata->base + RTC_YMR), &alarm->time);
201
202 alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
203 alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
204
205 return ret;
206 }
207
208 static int pl031_stv2_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
209 {
210 struct pl031_local *ldata = dev_get_drvdata(dev);
211 unsigned long time;
212 unsigned long bcd_year;
213 int ret;
214
215 /* At the moment, we can only deal with non-wildcarded alarm times. */
216 ret = rtc_valid_tm(&alarm->time);
217 if (ret == 0) {
218 ret = pl031_stv2_tm_to_time(dev, &alarm->time,
219 &time, &bcd_year);
220 if (ret == 0) {
221 writel(bcd_year, ldata->base + RTC_YMR);
222 writel(time, ldata->base + RTC_MR);
223
224 pl031_alarm_irq_enable(dev, alarm->enabled);
225 }
226 }
227
228 return ret;
229 }
230
231 static irqreturn_t pl031_interrupt(int irq, void *dev_id)
232 {
233 struct pl031_local *ldata = dev_id;
234 unsigned long rtcmis;
235 unsigned long events = 0;
236
237 rtcmis = readl(ldata->base + RTC_MIS);
238 if (rtcmis & RTC_BIT_AI) {
239 writel(RTC_BIT_AI, ldata->base + RTC_ICR);
240 events |= (RTC_AF | RTC_IRQF);
241 rtc_update_irq(ldata->rtc, 1, events);
242
243 return IRQ_HANDLED;
244 }
245
246 return IRQ_NONE;
247 }
248
249 static int pl031_read_time(struct device *dev, struct rtc_time *tm)
250 {
251 struct pl031_local *ldata = dev_get_drvdata(dev);
252
253 rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);
254
255 return 0;
256 }
257
258 static int pl031_set_time(struct device *dev, struct rtc_time *tm)
259 {
260 unsigned long time;
261 struct pl031_local *ldata = dev_get_drvdata(dev);
262 int ret;
263
264 ret = rtc_tm_to_time(tm, &time);
265
266 if (ret == 0)
267 writel(time, ldata->base + RTC_LR);
268
269 return ret;
270 }
271
272 static int pl031_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
273 {
274 struct pl031_local *ldata = dev_get_drvdata(dev);
275
276 rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
277
278 alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
279 alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
280
281 return 0;
282 }
283
284 static int pl031_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
285 {
286 struct pl031_local *ldata = dev_get_drvdata(dev);
287 unsigned long time;
288 int ret;
289
290 /* At the moment, we can only deal with non-wildcarded alarm times. */
291 ret = rtc_valid_tm(&alarm->time);
292 if (ret == 0) {
293 ret = rtc_tm_to_time(&alarm->time, &time);
294 if (ret == 0) {
295 writel(time, ldata->base + RTC_MR);
296 pl031_alarm_irq_enable(dev, alarm->enabled);
297 }
298 }
299
300 return ret;
301 }
302
303 static int pl031_remove(struct amba_device *adev)
304 {
305 struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
306
307 amba_set_drvdata(adev, NULL);
308 free_irq(adev->irq[0], ldata->rtc);
309 rtc_device_unregister(ldata->rtc);
310 iounmap(ldata->base);
311 kfree(ldata);
312 amba_release_regions(adev);
313
314 return 0;
315 }
316
317 static 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;
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 /* Enable the clockwatch on ST Variants */
349 if (vendor->clockwatch)
350 writel(readl(ldata->base + RTC_CR) | RTC_CR_CWEN,
351 ldata->base + RTC_CR);
352
353 /*
354 * On ST PL031 variants, the RTC reset value does not provide correct
355 * weekday for 2000-01-01. Correct the erroneous sunday to saturday.
356 */
357 if (vendor->st_weekday) {
358 if (readl(ldata->base + RTC_YDR) == 0x2000) {
359 time = readl(ldata->base + RTC_DR);
360 if ((time &
361 (RTC_MON_MASK | RTC_MDAY_MASK | RTC_WDAY_MASK))
362 == 0x02120000) {
363 time = time | (0x7 << RTC_WDAY_SHIFT);
364 writel(0x2000, ldata->base + RTC_YLR);
365 writel(time, ldata->base + RTC_LR);
366 }
367 }
368 }
369
370 ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
371 THIS_MODULE);
372 if (IS_ERR(ldata->rtc)) {
373 ret = PTR_ERR(ldata->rtc);
374 goto out_no_rtc;
375 }
376
377 if (request_irq(adev->irq[0], pl031_interrupt,
378 vendor->irqflags, "rtc-pl031", ldata)) {
379 ret = -EIO;
380 goto out_no_irq;
381 }
382
383 return 0;
384
385 out_no_irq:
386 rtc_device_unregister(ldata->rtc);
387 out_no_rtc:
388 iounmap(ldata->base);
389 amba_set_drvdata(adev, NULL);
390 out_no_remap:
391 kfree(ldata);
392 out:
393 amba_release_regions(adev);
394 err_req:
395
396 return ret;
397 }
398
399 /* Operations for the original ARM version */
400 static struct pl031_vendor_data arm_pl031 = {
401 .ops = {
402 .read_time = pl031_read_time,
403 .set_time = pl031_set_time,
404 .read_alarm = pl031_read_alarm,
405 .set_alarm = pl031_set_alarm,
406 .alarm_irq_enable = pl031_alarm_irq_enable,
407 },
408 .irqflags = IRQF_NO_SUSPEND,
409 };
410
411 /* The First ST derivative */
412 static struct pl031_vendor_data stv1_pl031 = {
413 .ops = {
414 .read_time = pl031_read_time,
415 .set_time = pl031_set_time,
416 .read_alarm = pl031_read_alarm,
417 .set_alarm = pl031_set_alarm,
418 .alarm_irq_enable = pl031_alarm_irq_enable,
419 },
420 .clockwatch = true,
421 .st_weekday = true,
422 .irqflags = IRQF_NO_SUSPEND,
423 };
424
425 /* And the second ST derivative */
426 static struct pl031_vendor_data stv2_pl031 = {
427 .ops = {
428 .read_time = pl031_stv2_read_time,
429 .set_time = pl031_stv2_set_time,
430 .read_alarm = pl031_stv2_read_alarm,
431 .set_alarm = pl031_stv2_set_alarm,
432 .alarm_irq_enable = pl031_alarm_irq_enable,
433 },
434 .clockwatch = true,
435 .st_weekday = true,
436 /*
437 * This variant shares the IRQ with another block and must not
438 * suspend that IRQ line.
439 */
440 .irqflags = IRQF_SHARED | IRQF_NO_SUSPEND,
441 };
442
443 static struct amba_id pl031_ids[] = {
444 {
445 .id = 0x00041031,
446 .mask = 0x000fffff,
447 .data = &arm_pl031,
448 },
449 /* ST Micro variants */
450 {
451 .id = 0x00180031,
452 .mask = 0x00ffffff,
453 .data = &stv1_pl031,
454 },
455 {
456 .id = 0x00280031,
457 .mask = 0x00ffffff,
458 .data = &stv2_pl031,
459 },
460 {0, 0},
461 };
462
463 MODULE_DEVICE_TABLE(amba, pl031_ids);
464
465 static struct amba_driver pl031_driver = {
466 .drv = {
467 .name = "rtc-pl031",
468 },
469 .id_table = pl031_ids,
470 .probe = pl031_probe,
471 .remove = pl031_remove,
472 };
473
474 module_amba_driver(pl031_driver);
475
476 MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net");
477 MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
478 MODULE_LICENSE("GPL");
Linux 2.6 libata-dev (mirror)