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v4.6
 
  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");
v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * drivers/rtc/rtc-pl031.c
  4 *
  5 * Real Time Clock interface for ARM AMBA PrimeCell 031 RTC
  6 *
  7 * Author: Deepak Saxena <dsaxena@plexity.net>
  8 *
  9 * Copyright 2006 (c) MontaVista Software, Inc.
 10 *
 11 * Author: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
 12 * Copyright 2010 (c) ST-Ericsson AB
 
 
 
 
 
 13 */
 14#include <linux/module.h>
 15#include <linux/rtc.h>
 16#include <linux/init.h>
 17#include <linux/interrupt.h>
 18#include <linux/amba/bus.h>
 19#include <linux/io.h>
 20#include <linux/bcd.h>
 21#include <linux/delay.h>
 22#include <linux/pm_wakeirq.h>
 23#include <linux/slab.h>
 24
 25/*
 26 * Register definitions
 27 */
 28#define	RTC_DR		0x00	/* Data read register */
 29#define	RTC_MR		0x04	/* Match register */
 30#define	RTC_LR		0x08	/* Data load register */
 31#define	RTC_CR		0x0c	/* Control register */
 32#define	RTC_IMSC	0x10	/* Interrupt mask and set register */
 33#define	RTC_RIS		0x14	/* Raw interrupt status register */
 34#define	RTC_MIS		0x18	/* Masked interrupt status register */
 35#define	RTC_ICR		0x1c	/* Interrupt clear register */
 36/* ST variants have additional timer functionality */
 37#define RTC_TDR		0x20	/* Timer data read register */
 38#define RTC_TLR		0x24	/* Timer data load register */
 39#define RTC_TCR		0x28	/* Timer control register */
 40#define RTC_YDR		0x30	/* Year data read register */
 41#define RTC_YMR		0x34	/* Year match register */
 42#define RTC_YLR		0x38	/* Year data load register */
 43
 44#define RTC_CR_EN	(1 << 0)	/* counter enable bit */
 45#define RTC_CR_CWEN	(1 << 26)	/* Clockwatch enable bit */
 46
 47#define RTC_TCR_EN	(1 << 1) /* Periodic timer enable bit */
 48
 49/* Common bit definitions for Interrupt status and control registers */
 50#define RTC_BIT_AI	(1 << 0) /* Alarm interrupt bit */
 51#define RTC_BIT_PI	(1 << 1) /* Periodic interrupt bit. ST variants only. */
 52
 53/* Common bit definations for ST v2 for reading/writing time */
 54#define RTC_SEC_SHIFT 0
 55#define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
 56#define RTC_MIN_SHIFT 6
 57#define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
 58#define RTC_HOUR_SHIFT 12
 59#define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
 60#define RTC_WDAY_SHIFT 17
 61#define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
 62#define RTC_MDAY_SHIFT 20
 63#define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
 64#define RTC_MON_SHIFT 25
 65#define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */
 66
 67#define RTC_TIMER_FREQ 32768
 68
 69/**
 70 * struct pl031_vendor_data - per-vendor variations
 71 * @ops: the vendor-specific operations used on this silicon version
 72 * @clockwatch: if this is an ST Microelectronics silicon version with a
 73 *	clockwatch function
 74 * @st_weekday: if this is an ST Microelectronics silicon version that need
 75 *	the weekday fix
 76 * @irqflags: special IRQ flags per variant
 77 */
 78struct pl031_vendor_data {
 79	struct rtc_class_ops ops;
 80	bool clockwatch;
 81	bool st_weekday;
 82	unsigned long irqflags;
 83};
 84
 85struct pl031_local {
 86	struct pl031_vendor_data *vendor;
 87	struct rtc_device *rtc;
 88	void __iomem *base;
 89};
 90
 91static int pl031_alarm_irq_enable(struct device *dev,
 92	unsigned int enabled)
 93{
 94	struct pl031_local *ldata = dev_get_drvdata(dev);
 95	unsigned long imsc;
 96
 97	/* Clear any pending alarm interrupts. */
 98	writel(RTC_BIT_AI, ldata->base + RTC_ICR);
 99
100	imsc = readl(ldata->base + RTC_IMSC);
101
102	if (enabled == 1)
103		writel(imsc | RTC_BIT_AI, ldata->base + RTC_IMSC);
104	else
105		writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
106
107	return 0;
108}
109
110/*
111 * Convert Gregorian date to ST v2 RTC format.
112 */
113static int pl031_stv2_tm_to_time(struct device *dev,
114				 struct rtc_time *tm, unsigned long *st_time,
115	unsigned long *bcd_year)
116{
117	int year = tm->tm_year + 1900;
118	int wday = tm->tm_wday;
119
120	/* wday masking is not working in hardware so wday must be valid */
121	if (wday < -1 || wday > 6) {
122		dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
123		return -EINVAL;
124	} else if (wday == -1) {
125		/* wday is not provided, calculate it here */
126		unsigned long time;
127		struct rtc_time calc_tm;
128
129		rtc_tm_to_time(tm, &time);
130		rtc_time_to_tm(time, &calc_tm);
131		wday = calc_tm.tm_wday;
132	}
133
134	*bcd_year = (bin2bcd(year % 100) | bin2bcd(year / 100) << 8);
135
136	*st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
137			|	(tm->tm_mday << RTC_MDAY_SHIFT)
138			|	((wday + 1) << RTC_WDAY_SHIFT)
139			|	(tm->tm_hour << RTC_HOUR_SHIFT)
140			|	(tm->tm_min << RTC_MIN_SHIFT)
141			|	(tm->tm_sec << RTC_SEC_SHIFT);
142
143	return 0;
144}
145
146/*
147 * Convert ST v2 RTC format to Gregorian date.
148 */
149static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
150	struct rtc_time *tm)
151{
152	tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
153	tm->tm_mon  = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
154	tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
155	tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
156	tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
157	tm->tm_min  = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
158	tm->tm_sec  = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
159
160	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
161	tm->tm_year -= 1900;
162
163	return 0;
164}
165
166static int pl031_stv2_read_time(struct device *dev, struct rtc_time *tm)
167{
168	struct pl031_local *ldata = dev_get_drvdata(dev);
169
170	pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
171			readl(ldata->base + RTC_YDR), tm);
172
173	return 0;
174}
175
176static int pl031_stv2_set_time(struct device *dev, struct rtc_time *tm)
177{
178	unsigned long time;
179	unsigned long bcd_year;
180	struct pl031_local *ldata = dev_get_drvdata(dev);
181	int ret;
182
183	ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
184	if (ret == 0) {
185		writel(bcd_year, ldata->base + RTC_YLR);
186		writel(time, ldata->base + RTC_LR);
187	}
188
189	return ret;
190}
191
192static int pl031_stv2_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
193{
194	struct pl031_local *ldata = dev_get_drvdata(dev);
195	int ret;
196
197	ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
198			readl(ldata->base + RTC_YMR), &alarm->time);
199
200	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
201	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
202
203	return ret;
204}
205
206static int pl031_stv2_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
207{
208	struct pl031_local *ldata = dev_get_drvdata(dev);
209	unsigned long time;
210	unsigned long bcd_year;
211	int ret;
212
213	/* At the moment, we can only deal with non-wildcarded alarm times. */
214	ret = rtc_valid_tm(&alarm->time);
215	if (ret == 0) {
216		ret = pl031_stv2_tm_to_time(dev, &alarm->time,
217					    &time, &bcd_year);
218		if (ret == 0) {
219			writel(bcd_year, ldata->base + RTC_YMR);
220			writel(time, ldata->base + RTC_MR);
221
222			pl031_alarm_irq_enable(dev, alarm->enabled);
223		}
224	}
225
226	return ret;
227}
228
229static irqreturn_t pl031_interrupt(int irq, void *dev_id)
230{
231	struct pl031_local *ldata = dev_id;
232	unsigned long rtcmis;
233	unsigned long events = 0;
234
235	rtcmis = readl(ldata->base + RTC_MIS);
236	if (rtcmis & RTC_BIT_AI) {
237		writel(RTC_BIT_AI, ldata->base + RTC_ICR);
238		events |= (RTC_AF | RTC_IRQF);
239		rtc_update_irq(ldata->rtc, 1, events);
240
241		return IRQ_HANDLED;
242	}
243
244	return IRQ_NONE;
245}
246
247static int pl031_read_time(struct device *dev, struct rtc_time *tm)
248{
249	struct pl031_local *ldata = dev_get_drvdata(dev);
250
251	rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);
252
253	return 0;
254}
255
256static int pl031_set_time(struct device *dev, struct rtc_time *tm)
257{
258	unsigned long time;
259	struct pl031_local *ldata = dev_get_drvdata(dev);
260	int ret;
261
262	ret = rtc_tm_to_time(tm, &time);
263
264	if (ret == 0)
265		writel(time, ldata->base + RTC_LR);
266
267	return ret;
268}
269
270static int pl031_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
271{
272	struct pl031_local *ldata = dev_get_drvdata(dev);
273
274	rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
275
276	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
277	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
278
279	return 0;
280}
281
282static int pl031_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
283{
284	struct pl031_local *ldata = dev_get_drvdata(dev);
285	unsigned long time;
286	int ret;
287
288	/* At the moment, we can only deal with non-wildcarded alarm times. */
289	ret = rtc_valid_tm(&alarm->time);
290	if (ret == 0) {
291		ret = rtc_tm_to_time(&alarm->time, &time);
292		if (ret == 0) {
293			writel(time, ldata->base + RTC_MR);
294			pl031_alarm_irq_enable(dev, alarm->enabled);
295		}
296	}
297
298	return ret;
299}
300
301static int pl031_remove(struct amba_device *adev)
302{
303	struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
304
305	dev_pm_clear_wake_irq(&adev->dev);
306	device_init_wakeup(&adev->dev, false);
307	if (adev->irq[0])
308		free_irq(adev->irq[0], ldata);
 
 
309	amba_release_regions(adev);
310
311	return 0;
312}
313
314static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
315{
316	int ret;
317	struct pl031_local *ldata;
318	struct pl031_vendor_data *vendor = id->data;
319	struct rtc_class_ops *ops;
320	unsigned long time, data;
321
322	ret = amba_request_regions(adev, NULL);
323	if (ret)
324		goto err_req;
325
326	ldata = devm_kzalloc(&adev->dev, sizeof(struct pl031_local),
327			     GFP_KERNEL);
328	ops = devm_kmemdup(&adev->dev, &vendor->ops, sizeof(vendor->ops),
329			   GFP_KERNEL);
330	if (!ldata || !ops) {
331		ret = -ENOMEM;
332		goto out;
333	}
 
 
 
334
335	ldata->vendor = vendor;
336	ldata->base = devm_ioremap(&adev->dev, adev->res.start,
337				   resource_size(&adev->res));
338	if (!ldata->base) {
339		ret = -ENOMEM;
340		goto out;
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	if (!adev->irq[0]) {
374		/* When there's no interrupt, no point in exposing the alarm */
375		ops->read_alarm = NULL;
376		ops->set_alarm = NULL;
377		ops->alarm_irq_enable = NULL;
 
378	}
379
380	device_init_wakeup(&adev->dev, true);
381	ldata->rtc = devm_rtc_allocate_device(&adev->dev);
382	if (IS_ERR(ldata->rtc))
383		return PTR_ERR(ldata->rtc);
384
385	ldata->rtc->ops = ops;
386
387	ret = rtc_register_device(ldata->rtc);
388	if (ret)
389		goto out;
390
391	if (adev->irq[0]) {
392		ret = request_irq(adev->irq[0], pl031_interrupt,
393				  vendor->irqflags, "rtc-pl031", ldata);
394		if (ret)
395			goto out;
396		dev_pm_set_wake_irq(&adev->dev, adev->irq[0]);
397	}
 
398	return 0;
399
 
 
 
 
 
 
400out:
401	amba_release_regions(adev);
402err_req:
403
404	return ret;
405}
406
407/* Operations for the original ARM version */
408static struct pl031_vendor_data arm_pl031 = {
409	.ops = {
410		.read_time = pl031_read_time,
411		.set_time = pl031_set_time,
412		.read_alarm = pl031_read_alarm,
413		.set_alarm = pl031_set_alarm,
414		.alarm_irq_enable = pl031_alarm_irq_enable,
415	},
416};
417
418/* The First ST derivative */
419static struct pl031_vendor_data stv1_pl031 = {
420	.ops = {
421		.read_time = pl031_read_time,
422		.set_time = pl031_set_time,
423		.read_alarm = pl031_read_alarm,
424		.set_alarm = pl031_set_alarm,
425		.alarm_irq_enable = pl031_alarm_irq_enable,
426	},
427	.clockwatch = true,
428	.st_weekday = true,
429};
430
431/* And the second ST derivative */
432static struct pl031_vendor_data stv2_pl031 = {
433	.ops = {
434		.read_time = pl031_stv2_read_time,
435		.set_time = pl031_stv2_set_time,
436		.read_alarm = pl031_stv2_read_alarm,
437		.set_alarm = pl031_stv2_set_alarm,
438		.alarm_irq_enable = pl031_alarm_irq_enable,
439	},
440	.clockwatch = true,
441	.st_weekday = true,
442	/*
443	 * This variant shares the IRQ with another block and must not
444	 * suspend that IRQ line.
445	 * TODO check if it shares with IRQF_NO_SUSPEND user, else we can
446	 * remove IRQF_COND_SUSPEND
447	 */
448	.irqflags = IRQF_SHARED | IRQF_COND_SUSPEND,
449};
450
451static const struct amba_id pl031_ids[] = {
452	{
453		.id = 0x00041031,
454		.mask = 0x000fffff,
455		.data = &arm_pl031,
456	},
457	/* ST Micro variants */
458	{
459		.id = 0x00180031,
460		.mask = 0x00ffffff,
461		.data = &stv1_pl031,
462	},
463	{
464		.id = 0x00280031,
465		.mask = 0x00ffffff,
466		.data = &stv2_pl031,
467	},
468	{0, 0},
469};
470
471MODULE_DEVICE_TABLE(amba, pl031_ids);
472
473static struct amba_driver pl031_driver = {
474	.drv = {
475		.name = "rtc-pl031",
476	},
477	.id_table = pl031_ids,
478	.probe = pl031_probe,
479	.remove = pl031_remove,
480};
481
482module_amba_driver(pl031_driver);
483
484MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
485MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
486MODULE_LICENSE("GPL");