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v3.5.6
  1/*
  2 * Copyright 2004-2008 Freescale Semiconductor, Inc. All Rights Reserved.
  3 *
  4 * The code contained herein is licensed under the GNU General Public
  5 * License. You may obtain a copy of the GNU General Public License
  6 * Version 2 or later at the following locations:
  7 *
  8 * http://www.opensource.org/licenses/gpl-license.html
  9 * http://www.gnu.org/copyleft/gpl.html
 10 */
 11
 12#include <linux/io.h>
 13#include <linux/rtc.h>
 14#include <linux/module.h>
 15#include <linux/slab.h>
 16#include <linux/interrupt.h>
 17#include <linux/platform_device.h>
 
 18#include <linux/clk.h>
 19
 20#include <mach/hardware.h>
 21
 22#define RTC_INPUT_CLK_32768HZ	(0x00 << 5)
 23#define RTC_INPUT_CLK_32000HZ	(0x01 << 5)
 24#define RTC_INPUT_CLK_38400HZ	(0x02 << 5)
 25
 26#define RTC_SW_BIT      (1 << 0)
 27#define RTC_ALM_BIT     (1 << 2)
 28#define RTC_1HZ_BIT     (1 << 4)
 29#define RTC_2HZ_BIT     (1 << 7)
 30#define RTC_SAM0_BIT    (1 << 8)
 31#define RTC_SAM1_BIT    (1 << 9)
 32#define RTC_SAM2_BIT    (1 << 10)
 33#define RTC_SAM3_BIT    (1 << 11)
 34#define RTC_SAM4_BIT    (1 << 12)
 35#define RTC_SAM5_BIT    (1 << 13)
 36#define RTC_SAM6_BIT    (1 << 14)
 37#define RTC_SAM7_BIT    (1 << 15)
 38#define PIT_ALL_ON      (RTC_2HZ_BIT | RTC_SAM0_BIT | RTC_SAM1_BIT | \
 39			 RTC_SAM2_BIT | RTC_SAM3_BIT | RTC_SAM4_BIT | \
 40			 RTC_SAM5_BIT | RTC_SAM6_BIT | RTC_SAM7_BIT)
 41
 42#define RTC_ENABLE_BIT  (1 << 7)
 43
 44#define MAX_PIE_NUM     9
 45#define MAX_PIE_FREQ    512
 46static const u32 PIE_BIT_DEF[MAX_PIE_NUM][2] = {
 47	{ 2,		RTC_2HZ_BIT },
 48	{ 4,		RTC_SAM0_BIT },
 49	{ 8,		RTC_SAM1_BIT },
 50	{ 16,		RTC_SAM2_BIT },
 51	{ 32,		RTC_SAM3_BIT },
 52	{ 64,		RTC_SAM4_BIT },
 53	{ 128,		RTC_SAM5_BIT },
 54	{ 256,		RTC_SAM6_BIT },
 55	{ MAX_PIE_FREQ,	RTC_SAM7_BIT },
 56};
 57
 58#define MXC_RTC_TIME	0
 59#define MXC_RTC_ALARM	1
 60
 61#define RTC_HOURMIN	0x00	/*  32bit rtc hour/min counter reg */
 62#define RTC_SECOND	0x04	/*  32bit rtc seconds counter reg */
 63#define RTC_ALRM_HM	0x08	/*  32bit rtc alarm hour/min reg */
 64#define RTC_ALRM_SEC	0x0C	/*  32bit rtc alarm seconds reg */
 65#define RTC_RTCCTL	0x10	/*  32bit rtc control reg */
 66#define RTC_RTCISR	0x14	/*  32bit rtc interrupt status reg */
 67#define RTC_RTCIENR	0x18	/*  32bit rtc interrupt enable reg */
 68#define RTC_STPWCH	0x1C	/*  32bit rtc stopwatch min reg */
 69#define RTC_DAYR	0x20	/*  32bit rtc days counter reg */
 70#define RTC_DAYALARM	0x24	/*  32bit rtc day alarm reg */
 71#define RTC_TEST1	0x28	/*  32bit rtc test reg 1 */
 72#define RTC_TEST2	0x2C	/*  32bit rtc test reg 2 */
 73#define RTC_TEST3	0x30	/*  32bit rtc test reg 3 */
 74
 
 
 
 
 
 75struct rtc_plat_data {
 76	struct rtc_device *rtc;
 77	void __iomem *ioaddr;
 78	int irq;
 79	struct clk *clk;
 
 80	struct rtc_time g_rtc_alarm;
 
 81};
 82
 
 
 
 
 
 
 
 
 
 
 
 
 83/*
 84 * This function is used to obtain the RTC time or the alarm value in
 85 * second.
 86 */
 87static u32 get_alarm_or_time(struct device *dev, int time_alarm)
 88{
 89	struct platform_device *pdev = to_platform_device(dev);
 90	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
 91	void __iomem *ioaddr = pdata->ioaddr;
 92	u32 day = 0, hr = 0, min = 0, sec = 0, hr_min = 0;
 93
 94	switch (time_alarm) {
 95	case MXC_RTC_TIME:
 96		day = readw(ioaddr + RTC_DAYR);
 97		hr_min = readw(ioaddr + RTC_HOURMIN);
 98		sec = readw(ioaddr + RTC_SECOND);
 99		break;
100	case MXC_RTC_ALARM:
101		day = readw(ioaddr + RTC_DAYALARM);
102		hr_min = readw(ioaddr + RTC_ALRM_HM) & 0xffff;
103		sec = readw(ioaddr + RTC_ALRM_SEC);
104		break;
105	}
106
107	hr = hr_min >> 8;
108	min = hr_min & 0xff;
109
110	return (((day * 24 + hr) * 60) + min) * 60 + sec;
111}
112
113/*
114 * This function sets the RTC alarm value or the time value.
115 */
116static void set_alarm_or_time(struct device *dev, int time_alarm, u32 time)
117{
118	u32 day, hr, min, sec, temp;
119	struct platform_device *pdev = to_platform_device(dev);
120	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
121	void __iomem *ioaddr = pdata->ioaddr;
122
123	day = time / 86400;
124	time -= day * 86400;
125
126	/* time is within a day now */
127	hr = time / 3600;
128	time -= hr * 3600;
129
130	/* time is within an hour now */
131	min = time / 60;
132	sec = time - min * 60;
133
134	temp = (hr << 8) + min;
135
136	switch (time_alarm) {
137	case MXC_RTC_TIME:
138		writew(day, ioaddr + RTC_DAYR);
139		writew(sec, ioaddr + RTC_SECOND);
140		writew(temp, ioaddr + RTC_HOURMIN);
141		break;
142	case MXC_RTC_ALARM:
143		writew(day, ioaddr + RTC_DAYALARM);
144		writew(sec, ioaddr + RTC_ALRM_SEC);
145		writew(temp, ioaddr + RTC_ALRM_HM);
146		break;
147	}
148}
149
150/*
151 * This function updates the RTC alarm registers and then clears all the
152 * interrupt status bits.
153 */
154static int rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
155{
156	struct rtc_time alarm_tm, now_tm;
157	unsigned long now, time;
158	struct platform_device *pdev = to_platform_device(dev);
159	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
160	void __iomem *ioaddr = pdata->ioaddr;
161
162	now = get_alarm_or_time(dev, MXC_RTC_TIME);
163	rtc_time_to_tm(now, &now_tm);
164	alarm_tm.tm_year = now_tm.tm_year;
165	alarm_tm.tm_mon = now_tm.tm_mon;
166	alarm_tm.tm_mday = now_tm.tm_mday;
167	alarm_tm.tm_hour = alrm->tm_hour;
168	alarm_tm.tm_min = alrm->tm_min;
169	alarm_tm.tm_sec = alrm->tm_sec;
170	rtc_tm_to_time(&alarm_tm, &time);
171
172	/* clear all the interrupt status bits */
173	writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
174	set_alarm_or_time(dev, MXC_RTC_ALARM, time);
175
176	return 0;
177}
178
179static void mxc_rtc_irq_enable(struct device *dev, unsigned int bit,
180				unsigned int enabled)
181{
182	struct platform_device *pdev = to_platform_device(dev);
183	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
184	void __iomem *ioaddr = pdata->ioaddr;
185	u32 reg;
 
186
187	spin_lock_irq(&pdata->rtc->irq_lock);
188	reg = readw(ioaddr + RTC_RTCIENR);
189
190	if (enabled)
191		reg |= bit;
192	else
193		reg &= ~bit;
194
195	writew(reg, ioaddr + RTC_RTCIENR);
196	spin_unlock_irq(&pdata->rtc->irq_lock);
197}
198
199/* This function is the RTC interrupt service routine. */
200static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
201{
202	struct platform_device *pdev = dev_id;
203	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
204	void __iomem *ioaddr = pdata->ioaddr;
205	unsigned long flags;
206	u32 status;
207	u32 events = 0;
208
209	spin_lock_irqsave(&pdata->rtc->irq_lock, flags);
210	status = readw(ioaddr + RTC_RTCISR) & readw(ioaddr + RTC_RTCIENR);
211	/* clear interrupt sources */
212	writew(status, ioaddr + RTC_RTCISR);
213
214	/* update irq data & counter */
215	if (status & RTC_ALM_BIT) {
216		events |= (RTC_AF | RTC_IRQF);
217		/* RTC alarm should be one-shot */
218		mxc_rtc_irq_enable(&pdev->dev, RTC_ALM_BIT, 0);
219	}
220
221	if (status & RTC_1HZ_BIT)
222		events |= (RTC_UF | RTC_IRQF);
223
224	if (status & PIT_ALL_ON)
225		events |= (RTC_PF | RTC_IRQF);
226
227	rtc_update_irq(pdata->rtc, 1, events);
228	spin_unlock_irqrestore(&pdata->rtc->irq_lock, flags);
229
230	return IRQ_HANDLED;
231}
232
233/*
234 * Clear all interrupts and release the IRQ
235 */
236static void mxc_rtc_release(struct device *dev)
237{
238	struct platform_device *pdev = to_platform_device(dev);
239	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
240	void __iomem *ioaddr = pdata->ioaddr;
241
242	spin_lock_irq(&pdata->rtc->irq_lock);
243
244	/* Disable all rtc interrupts */
245	writew(0, ioaddr + RTC_RTCIENR);
246
247	/* Clear all interrupt status */
248	writew(0xffffffff, ioaddr + RTC_RTCISR);
249
250	spin_unlock_irq(&pdata->rtc->irq_lock);
251}
252
253static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
254{
255	mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
256	return 0;
257}
258
259/*
260 * This function reads the current RTC time into tm in Gregorian date.
261 */
262static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
263{
264	u32 val;
265
266	/* Avoid roll-over from reading the different registers */
267	do {
268		val = get_alarm_or_time(dev, MXC_RTC_TIME);
269	} while (val != get_alarm_or_time(dev, MXC_RTC_TIME));
270
271	rtc_time_to_tm(val, tm);
272
273	return 0;
274}
275
276/*
277 * This function sets the internal RTC time based on tm in Gregorian date.
278 */
279static int mxc_rtc_set_mmss(struct device *dev, unsigned long time)
280{
281	/*
282	 * TTC_DAYR register is 9-bit in MX1 SoC, save time and day of year only
283	 */
284	if (cpu_is_mx1()) {
285		struct rtc_time tm;
286
287		rtc_time_to_tm(time, &tm);
288		tm.tm_year = 70;
289		rtc_tm_to_time(&tm, &time);
290	}
291
292	/* Avoid roll-over from reading the different registers */
293	do {
294		set_alarm_or_time(dev, MXC_RTC_TIME, time);
295	} while (time != get_alarm_or_time(dev, MXC_RTC_TIME));
296
297	return 0;
298}
299
300/*
301 * This function reads the current alarm value into the passed in 'alrm'
302 * argument. It updates the alrm's pending field value based on the whether
303 * an alarm interrupt occurs or not.
304 */
305static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
306{
307	struct platform_device *pdev = to_platform_device(dev);
308	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
309	void __iomem *ioaddr = pdata->ioaddr;
310
311	rtc_time_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
312	alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;
313
314	return 0;
315}
316
317/*
318 * This function sets the RTC alarm based on passed in alrm.
319 */
320static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
321{
322	struct platform_device *pdev = to_platform_device(dev);
323	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
324	int ret;
325
326	ret = rtc_update_alarm(dev, &alrm->time);
327	if (ret)
328		return ret;
329
330	memcpy(&pdata->g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
331	mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
332
333	return 0;
334}
335
336/* RTC layer */
337static struct rtc_class_ops mxc_rtc_ops = {
338	.release		= mxc_rtc_release,
339	.read_time		= mxc_rtc_read_time,
340	.set_mmss		= mxc_rtc_set_mmss,
341	.read_alarm		= mxc_rtc_read_alarm,
342	.set_alarm		= mxc_rtc_set_alarm,
343	.alarm_irq_enable	= mxc_rtc_alarm_irq_enable,
344};
345
346static int __init mxc_rtc_probe(struct platform_device *pdev)
347{
348	struct resource *res;
349	struct rtc_device *rtc;
350	struct rtc_plat_data *pdata = NULL;
351	u32 reg;
352	unsigned long rate;
353	int ret;
354
355	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
356	if (!res)
357		return -ENODEV;
358
359	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
360	if (!pdata)
361		return -ENOMEM;
362
363	if (!devm_request_mem_region(&pdev->dev, res->start,
364				     resource_size(res), pdev->name))
365		return -EBUSY;
366
367	pdata->ioaddr = devm_ioremap(&pdev->dev, res->start,
368				     resource_size(res));
369
370	pdata->clk = clk_get(&pdev->dev, "rtc");
371	if (IS_ERR(pdata->clk)) {
372		dev_err(&pdev->dev, "unable to get clock!\n");
373		ret = PTR_ERR(pdata->clk);
374		goto exit_free_pdata;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
375	}
376
377	clk_enable(pdata->clk);
378	rate = clk_get_rate(pdata->clk);
 
 
 
 
 
379
380	if (rate == 32768)
381		reg = RTC_INPUT_CLK_32768HZ;
382	else if (rate == 32000)
383		reg = RTC_INPUT_CLK_32000HZ;
384	else if (rate == 38400)
385		reg = RTC_INPUT_CLK_38400HZ;
386	else {
387		dev_err(&pdev->dev, "rtc clock is not valid (%lu)\n", rate);
388		ret = -EINVAL;
389		goto exit_put_clk;
390	}
391
392	reg |= RTC_ENABLE_BIT;
393	writew(reg, (pdata->ioaddr + RTC_RTCCTL));
394	if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) {
395		dev_err(&pdev->dev, "hardware module can't be enabled!\n");
396		ret = -EIO;
397		goto exit_put_clk;
398	}
399
400	platform_set_drvdata(pdev, pdata);
401
402	/* Configure and enable the RTC */
403	pdata->irq = platform_get_irq(pdev, 0);
404
405	if (pdata->irq >= 0 &&
406	    devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
407			     IRQF_SHARED, pdev->name, pdev) < 0) {
408		dev_warn(&pdev->dev, "interrupt not available.\n");
409		pdata->irq = -1;
410	}
411
412	if (pdata->irq >=0)
413		device_init_wakeup(&pdev->dev, 1);
414
415	rtc = rtc_device_register(pdev->name, &pdev->dev, &mxc_rtc_ops,
416				  THIS_MODULE);
417	if (IS_ERR(rtc)) {
418		ret = PTR_ERR(rtc);
419		goto exit_clr_drvdata;
420	}
421
422	pdata->rtc = rtc;
423
424	return 0;
425
426exit_clr_drvdata:
427	platform_set_drvdata(pdev, NULL);
428exit_put_clk:
429	clk_disable(pdata->clk);
430	clk_put(pdata->clk);
431
432exit_free_pdata:
433
434	return ret;
435}
436
437static int __exit mxc_rtc_remove(struct platform_device *pdev)
438{
439	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
440
441	rtc_device_unregister(pdata->rtc);
442
443	clk_disable(pdata->clk);
444	clk_put(pdata->clk);
445	platform_set_drvdata(pdev, NULL);
446
447	return 0;
448}
449
450#ifdef CONFIG_PM
451static int mxc_rtc_suspend(struct device *dev)
452{
453	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
454
455	if (device_may_wakeup(dev))
456		enable_irq_wake(pdata->irq);
457
458	return 0;
459}
460
461static int mxc_rtc_resume(struct device *dev)
462{
463	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
464
465	if (device_may_wakeup(dev))
466		disable_irq_wake(pdata->irq);
467
468	return 0;
469}
470
471static struct dev_pm_ops mxc_rtc_pm_ops = {
472	.suspend	= mxc_rtc_suspend,
473	.resume		= mxc_rtc_resume,
474};
475#endif
476
477static struct platform_driver mxc_rtc_driver = {
478	.driver = {
479		   .name	= "mxc_rtc",
480#ifdef CONFIG_PM
481		   .pm		= &mxc_rtc_pm_ops,
482#endif
483		   .owner	= THIS_MODULE,
484	},
485	.remove		= __exit_p(mxc_rtc_remove),
486};
487
488static int __init mxc_rtc_init(void)
489{
490	return platform_driver_probe(&mxc_rtc_driver, mxc_rtc_probe);
491}
492
493static void __exit mxc_rtc_exit(void)
494{
495	platform_driver_unregister(&mxc_rtc_driver);
496}
497
498module_init(mxc_rtc_init);
499module_exit(mxc_rtc_exit);
500
501MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
502MODULE_DESCRIPTION("RTC driver for Freescale MXC");
503MODULE_LICENSE("GPL");
504
v6.2
  1// SPDX-License-Identifier: GPL-2.0+
  2//
  3// Copyright 2004-2008 Freescale Semiconductor, Inc. All Rights Reserved.
 
 
 
 
 
 
 
  4
  5#include <linux/io.h>
  6#include <linux/rtc.h>
  7#include <linux/module.h>
  8#include <linux/slab.h>
  9#include <linux/interrupt.h>
 10#include <linux/platform_device.h>
 11#include <linux/pm_wakeirq.h>
 12#include <linux/clk.h>
 13#include <linux/of.h>
 14#include <linux/of_device.h>
 15
 16#define RTC_INPUT_CLK_32768HZ	(0x00 << 5)
 17#define RTC_INPUT_CLK_32000HZ	(0x01 << 5)
 18#define RTC_INPUT_CLK_38400HZ	(0x02 << 5)
 19
 20#define RTC_SW_BIT      (1 << 0)
 21#define RTC_ALM_BIT     (1 << 2)
 22#define RTC_1HZ_BIT     (1 << 4)
 23#define RTC_2HZ_BIT     (1 << 7)
 24#define RTC_SAM0_BIT    (1 << 8)
 25#define RTC_SAM1_BIT    (1 << 9)
 26#define RTC_SAM2_BIT    (1 << 10)
 27#define RTC_SAM3_BIT    (1 << 11)
 28#define RTC_SAM4_BIT    (1 << 12)
 29#define RTC_SAM5_BIT    (1 << 13)
 30#define RTC_SAM6_BIT    (1 << 14)
 31#define RTC_SAM7_BIT    (1 << 15)
 32#define PIT_ALL_ON      (RTC_2HZ_BIT | RTC_SAM0_BIT | RTC_SAM1_BIT | \
 33			 RTC_SAM2_BIT | RTC_SAM3_BIT | RTC_SAM4_BIT | \
 34			 RTC_SAM5_BIT | RTC_SAM6_BIT | RTC_SAM7_BIT)
 35
 36#define RTC_ENABLE_BIT  (1 << 7)
 37
 38#define MAX_PIE_NUM     9
 39#define MAX_PIE_FREQ    512
 
 
 
 
 
 
 
 
 
 
 
 40
 41#define MXC_RTC_TIME	0
 42#define MXC_RTC_ALARM	1
 43
 44#define RTC_HOURMIN	0x00	/*  32bit rtc hour/min counter reg */
 45#define RTC_SECOND	0x04	/*  32bit rtc seconds counter reg */
 46#define RTC_ALRM_HM	0x08	/*  32bit rtc alarm hour/min reg */
 47#define RTC_ALRM_SEC	0x0C	/*  32bit rtc alarm seconds reg */
 48#define RTC_RTCCTL	0x10	/*  32bit rtc control reg */
 49#define RTC_RTCISR	0x14	/*  32bit rtc interrupt status reg */
 50#define RTC_RTCIENR	0x18	/*  32bit rtc interrupt enable reg */
 51#define RTC_STPWCH	0x1C	/*  32bit rtc stopwatch min reg */
 52#define RTC_DAYR	0x20	/*  32bit rtc days counter reg */
 53#define RTC_DAYALARM	0x24	/*  32bit rtc day alarm reg */
 54#define RTC_TEST1	0x28	/*  32bit rtc test reg 1 */
 55#define RTC_TEST2	0x2C	/*  32bit rtc test reg 2 */
 56#define RTC_TEST3	0x30	/*  32bit rtc test reg 3 */
 57
 58enum imx_rtc_type {
 59	IMX1_RTC,
 60	IMX21_RTC,
 61};
 62
 63struct rtc_plat_data {
 64	struct rtc_device *rtc;
 65	void __iomem *ioaddr;
 66	int irq;
 67	struct clk *clk_ref;
 68	struct clk *clk_ipg;
 69	struct rtc_time g_rtc_alarm;
 70	enum imx_rtc_type devtype;
 71};
 72
 73static const struct of_device_id imx_rtc_dt_ids[] = {
 74	{ .compatible = "fsl,imx1-rtc", .data = (const void *)IMX1_RTC },
 75	{ .compatible = "fsl,imx21-rtc", .data = (const void *)IMX21_RTC },
 76	{}
 77};
 78MODULE_DEVICE_TABLE(of, imx_rtc_dt_ids);
 79
 80static inline int is_imx1_rtc(struct rtc_plat_data *data)
 81{
 82	return data->devtype == IMX1_RTC;
 83}
 84
 85/*
 86 * This function is used to obtain the RTC time or the alarm value in
 87 * second.
 88 */
 89static time64_t get_alarm_or_time(struct device *dev, int time_alarm)
 90{
 91	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
 
 92	void __iomem *ioaddr = pdata->ioaddr;
 93	u32 day = 0, hr = 0, min = 0, sec = 0, hr_min = 0;
 94
 95	switch (time_alarm) {
 96	case MXC_RTC_TIME:
 97		day = readw(ioaddr + RTC_DAYR);
 98		hr_min = readw(ioaddr + RTC_HOURMIN);
 99		sec = readw(ioaddr + RTC_SECOND);
100		break;
101	case MXC_RTC_ALARM:
102		day = readw(ioaddr + RTC_DAYALARM);
103		hr_min = readw(ioaddr + RTC_ALRM_HM) & 0xffff;
104		sec = readw(ioaddr + RTC_ALRM_SEC);
105		break;
106	}
107
108	hr = hr_min >> 8;
109	min = hr_min & 0xff;
110
111	return ((((time64_t)day * 24 + hr) * 60) + min) * 60 + sec;
112}
113
114/*
115 * This function sets the RTC alarm value or the time value.
116 */
117static void set_alarm_or_time(struct device *dev, int time_alarm, time64_t time)
118{
119	u32 tod, day, hr, min, sec, temp;
120	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
 
121	void __iomem *ioaddr = pdata->ioaddr;
122
123	day = div_s64_rem(time, 86400, &tod);
 
124
125	/* time is within a day now */
126	hr = tod / 3600;
127	tod -= hr * 3600;
128
129	/* time is within an hour now */
130	min = tod / 60;
131	sec = tod - min * 60;
132
133	temp = (hr << 8) + min;
134
135	switch (time_alarm) {
136	case MXC_RTC_TIME:
137		writew(day, ioaddr + RTC_DAYR);
138		writew(sec, ioaddr + RTC_SECOND);
139		writew(temp, ioaddr + RTC_HOURMIN);
140		break;
141	case MXC_RTC_ALARM:
142		writew(day, ioaddr + RTC_DAYALARM);
143		writew(sec, ioaddr + RTC_ALRM_SEC);
144		writew(temp, ioaddr + RTC_ALRM_HM);
145		break;
146	}
147}
148
149/*
150 * This function updates the RTC alarm registers and then clears all the
151 * interrupt status bits.
152 */
153static void rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
154{
155	time64_t time;
156	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
 
 
157	void __iomem *ioaddr = pdata->ioaddr;
158
159	time = rtc_tm_to_time64(alrm);
 
 
 
 
 
 
 
 
160
161	/* clear all the interrupt status bits */
162	writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
163	set_alarm_or_time(dev, MXC_RTC_ALARM, time);
 
 
164}
165
166static void mxc_rtc_irq_enable(struct device *dev, unsigned int bit,
167				unsigned int enabled)
168{
169	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
 
170	void __iomem *ioaddr = pdata->ioaddr;
171	u32 reg;
172	unsigned long flags;
173
174	spin_lock_irqsave(&pdata->rtc->irq_lock, flags);
175	reg = readw(ioaddr + RTC_RTCIENR);
176
177	if (enabled)
178		reg |= bit;
179	else
180		reg &= ~bit;
181
182	writew(reg, ioaddr + RTC_RTCIENR);
183	spin_unlock_irqrestore(&pdata->rtc->irq_lock, flags);
184}
185
186/* This function is the RTC interrupt service routine. */
187static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
188{
189	struct platform_device *pdev = dev_id;
190	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
191	void __iomem *ioaddr = pdata->ioaddr;
 
192	u32 status;
193	u32 events = 0;
194
195	spin_lock(&pdata->rtc->irq_lock);
196	status = readw(ioaddr + RTC_RTCISR) & readw(ioaddr + RTC_RTCIENR);
197	/* clear interrupt sources */
198	writew(status, ioaddr + RTC_RTCISR);
199
200	/* update irq data & counter */
201	if (status & RTC_ALM_BIT) {
202		events |= (RTC_AF | RTC_IRQF);
203		/* RTC alarm should be one-shot */
204		mxc_rtc_irq_enable(&pdev->dev, RTC_ALM_BIT, 0);
205	}
206
 
 
 
207	if (status & PIT_ALL_ON)
208		events |= (RTC_PF | RTC_IRQF);
209
210	rtc_update_irq(pdata->rtc, 1, events);
211	spin_unlock(&pdata->rtc->irq_lock);
212
213	return IRQ_HANDLED;
214}
215
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
216static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
217{
218	mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
219	return 0;
220}
221
222/*
223 * This function reads the current RTC time into tm in Gregorian date.
224 */
225static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
226{
227	time64_t val;
228
229	/* Avoid roll-over from reading the different registers */
230	do {
231		val = get_alarm_or_time(dev, MXC_RTC_TIME);
232	} while (val != get_alarm_or_time(dev, MXC_RTC_TIME));
233
234	rtc_time64_to_tm(val, tm);
235
236	return 0;
237}
238
239/*
240 * This function sets the internal RTC time based on tm in Gregorian date.
241 */
242static int mxc_rtc_set_time(struct device *dev, struct rtc_time *tm)
243{
244	time64_t time = rtc_tm_to_time64(tm);
 
 
 
 
 
 
 
 
 
245
246	/* Avoid roll-over from reading the different registers */
247	do {
248		set_alarm_or_time(dev, MXC_RTC_TIME, time);
249	} while (time != get_alarm_or_time(dev, MXC_RTC_TIME));
250
251	return 0;
252}
253
254/*
255 * This function reads the current alarm value into the passed in 'alrm'
256 * argument. It updates the alrm's pending field value based on the whether
257 * an alarm interrupt occurs or not.
258 */
259static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
260{
261	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
 
262	void __iomem *ioaddr = pdata->ioaddr;
263
264	rtc_time64_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
265	alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;
266
267	return 0;
268}
269
270/*
271 * This function sets the RTC alarm based on passed in alrm.
272 */
273static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
274{
275	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
 
 
276
277	rtc_update_alarm(dev, &alrm->time);
 
 
278
279	memcpy(&pdata->g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
280	mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
281
282	return 0;
283}
284
285/* RTC layer */
286static const struct rtc_class_ops mxc_rtc_ops = {
 
287	.read_time		= mxc_rtc_read_time,
288	.set_time		= mxc_rtc_set_time,
289	.read_alarm		= mxc_rtc_read_alarm,
290	.set_alarm		= mxc_rtc_set_alarm,
291	.alarm_irq_enable	= mxc_rtc_alarm_irq_enable,
292};
293
294static int mxc_rtc_probe(struct platform_device *pdev)
295{
 
296	struct rtc_device *rtc;
297	struct rtc_plat_data *pdata = NULL;
298	u32 reg;
299	unsigned long rate;
300	int ret;
301
 
 
 
 
302	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
303	if (!pdata)
304		return -ENOMEM;
305
306	pdata->devtype = (uintptr_t)of_device_get_match_data(&pdev->dev);
307
308	pdata->ioaddr = devm_platform_ioremap_resource(pdev, 0);
309	if (IS_ERR(pdata->ioaddr))
310		return PTR_ERR(pdata->ioaddr);
311
312	rtc = devm_rtc_allocate_device(&pdev->dev);
313	if (IS_ERR(rtc))
314		return PTR_ERR(rtc);
315
316	pdata->rtc = rtc;
317	rtc->ops = &mxc_rtc_ops;
318	if (is_imx1_rtc(pdata)) {
319		struct rtc_time tm;
320
321		/* 9bit days + hours minutes seconds */
322		rtc->range_max = (1 << 9) * 86400 - 1;
323
324		/*
325		 * Set the start date as beginning of the current year. This can
326		 * be overridden using device tree.
327		 */
328		rtc_time64_to_tm(ktime_get_real_seconds(), &tm);
329		rtc->start_secs =  mktime64(tm.tm_year, 1, 1, 0, 0, 0);
330		rtc->set_start_time = true;
331	} else {
332		/* 16bit days + hours minutes seconds */
333		rtc->range_max = (1 << 16) * 86400ULL - 1;
334	}
335
336	pdata->clk_ipg = devm_clk_get_enabled(&pdev->dev, "ipg");
337	if (IS_ERR(pdata->clk_ipg)) {
338		dev_err(&pdev->dev, "unable to get ipg clock!\n");
339		return PTR_ERR(pdata->clk_ipg);
340	}
341
342	pdata->clk_ref = devm_clk_get_enabled(&pdev->dev, "ref");
343	if (IS_ERR(pdata->clk_ref)) {
344		dev_err(&pdev->dev, "unable to get ref clock!\n");
345		return PTR_ERR(pdata->clk_ref);
346	}
347
348	rate = clk_get_rate(pdata->clk_ref);
349
350	if (rate == 32768)
351		reg = RTC_INPUT_CLK_32768HZ;
352	else if (rate == 32000)
353		reg = RTC_INPUT_CLK_32000HZ;
354	else if (rate == 38400)
355		reg = RTC_INPUT_CLK_38400HZ;
356	else {
357		dev_err(&pdev->dev, "rtc clock is not valid (%lu)\n", rate);
358		return -EINVAL;
 
359	}
360
361	reg |= RTC_ENABLE_BIT;
362	writew(reg, (pdata->ioaddr + RTC_RTCCTL));
363	if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) {
364		dev_err(&pdev->dev, "hardware module can't be enabled!\n");
365		return -EIO;
 
366	}
367
368	platform_set_drvdata(pdev, pdata);
369
370	/* Configure and enable the RTC */
371	pdata->irq = platform_get_irq(pdev, 0);
372
373	if (pdata->irq >= 0 &&
374	    devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
375			     IRQF_SHARED, pdev->name, pdev) < 0) {
376		dev_warn(&pdev->dev, "interrupt not available.\n");
377		pdata->irq = -1;
378	}
379
380	if (pdata->irq >= 0) {
381		device_init_wakeup(&pdev->dev, 1);
382		ret = dev_pm_set_wake_irq(&pdev->dev, pdata->irq);
383		if (ret)
384			dev_err(&pdev->dev, "failed to enable irq wake\n");
 
 
 
385	}
386
387	ret = devm_rtc_register_device(rtc);
 
 
 
 
 
 
 
 
 
 
388
389	return ret;
390}
391
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
392static struct platform_driver mxc_rtc_driver = {
393	.driver = {
394		   .name	= "mxc_rtc",
395		   .of_match_table = imx_rtc_dt_ids,
 
 
 
396	},
397	.probe = mxc_rtc_probe,
398};
399
400module_platform_driver(mxc_rtc_driver)
 
 
 
 
 
 
 
 
 
 
 
401
402MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
403MODULE_DESCRIPTION("RTC driver for Freescale MXC");
404MODULE_LICENSE("GPL");
405