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v4.6
  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#include <linux/of.h>
 20#include <linux/of_device.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
 75enum imx_rtc_type {
 76	IMX1_RTC,
 77	IMX21_RTC,
 78};
 79
 80struct rtc_plat_data {
 81	struct rtc_device *rtc;
 82	void __iomem *ioaddr;
 83	int irq;
 84	struct clk *clk_ref;
 85	struct clk *clk_ipg;
 86	struct rtc_time g_rtc_alarm;
 87	enum imx_rtc_type devtype;
 88};
 89
 90static const struct platform_device_id imx_rtc_devtype[] = {
 91	{
 92		.name = "imx1-rtc",
 93		.driver_data = IMX1_RTC,
 94	}, {
 95		.name = "imx21-rtc",
 96		.driver_data = IMX21_RTC,
 97	}, {
 98		/* sentinel */
 99	}
100};
101MODULE_DEVICE_TABLE(platform, imx_rtc_devtype);
102
103#ifdef CONFIG_OF
104static const struct of_device_id imx_rtc_dt_ids[] = {
105	{ .compatible = "fsl,imx1-rtc", .data = (const void *)IMX1_RTC },
106	{ .compatible = "fsl,imx21-rtc", .data = (const void *)IMX21_RTC },
107	{}
108};
109MODULE_DEVICE_TABLE(of, imx_rtc_dt_ids);
110#endif
111
112static inline int is_imx1_rtc(struct rtc_plat_data *data)
113{
114	return data->devtype == IMX1_RTC;
115}
116
117/*
118 * This function is used to obtain the RTC time or the alarm value in
119 * second.
120 */
121static time64_t get_alarm_or_time(struct device *dev, int time_alarm)
122{
123	struct platform_device *pdev = to_platform_device(dev);
124	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
125	void __iomem *ioaddr = pdata->ioaddr;
126	u32 day = 0, hr = 0, min = 0, sec = 0, hr_min = 0;
127
128	switch (time_alarm) {
129	case MXC_RTC_TIME:
130		day = readw(ioaddr + RTC_DAYR);
131		hr_min = readw(ioaddr + RTC_HOURMIN);
132		sec = readw(ioaddr + RTC_SECOND);
133		break;
134	case MXC_RTC_ALARM:
135		day = readw(ioaddr + RTC_DAYALARM);
136		hr_min = readw(ioaddr + RTC_ALRM_HM) & 0xffff;
137		sec = readw(ioaddr + RTC_ALRM_SEC);
138		break;
139	}
140
141	hr = hr_min >> 8;
142	min = hr_min & 0xff;
143
144	return ((((time64_t)day * 24 + hr) * 60) + min) * 60 + sec;
145}
146
147/*
148 * This function sets the RTC alarm value or the time value.
149 */
150static void set_alarm_or_time(struct device *dev, int time_alarm, time64_t time)
151{
152	u32 tod, day, hr, min, sec, temp;
153	struct platform_device *pdev = to_platform_device(dev);
154	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
155	void __iomem *ioaddr = pdata->ioaddr;
156
157	day = div_s64_rem(time, 86400, &tod);
158
159	/* time is within a day now */
160	hr = tod / 3600;
161	tod -= hr * 3600;
162
163	/* time is within an hour now */
164	min = tod / 60;
165	sec = tod - min * 60;
166
167	temp = (hr << 8) + min;
168
169	switch (time_alarm) {
170	case MXC_RTC_TIME:
171		writew(day, ioaddr + RTC_DAYR);
172		writew(sec, ioaddr + RTC_SECOND);
173		writew(temp, ioaddr + RTC_HOURMIN);
174		break;
175	case MXC_RTC_ALARM:
176		writew(day, ioaddr + RTC_DAYALARM);
177		writew(sec, ioaddr + RTC_ALRM_SEC);
178		writew(temp, ioaddr + RTC_ALRM_HM);
179		break;
180	}
181}
182
183/*
184 * This function updates the RTC alarm registers and then clears all the
185 * interrupt status bits.
186 */
187static void rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
188{
189	time64_t time;
190	struct platform_device *pdev = to_platform_device(dev);
191	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
192	void __iomem *ioaddr = pdata->ioaddr;
193
194	time = rtc_tm_to_time64(alrm);
195
196	/* clear all the interrupt status bits */
197	writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
198	set_alarm_or_time(dev, MXC_RTC_ALARM, time);
199}
200
201static void mxc_rtc_irq_enable(struct device *dev, unsigned int bit,
202				unsigned int enabled)
203{
204	struct platform_device *pdev = to_platform_device(dev);
205	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
206	void __iomem *ioaddr = pdata->ioaddr;
207	u32 reg;
208
209	spin_lock_irq(&pdata->rtc->irq_lock);
210	reg = readw(ioaddr + RTC_RTCIENR);
211
212	if (enabled)
213		reg |= bit;
214	else
215		reg &= ~bit;
216
217	writew(reg, ioaddr + RTC_RTCIENR);
218	spin_unlock_irq(&pdata->rtc->irq_lock);
219}
220
221/* This function is the RTC interrupt service routine. */
222static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
223{
224	struct platform_device *pdev = dev_id;
225	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
226	void __iomem *ioaddr = pdata->ioaddr;
227	unsigned long flags;
228	u32 status;
229	u32 events = 0;
230
231	spin_lock_irqsave(&pdata->rtc->irq_lock, flags);
232	status = readw(ioaddr + RTC_RTCISR) & readw(ioaddr + RTC_RTCIENR);
233	/* clear interrupt sources */
234	writew(status, ioaddr + RTC_RTCISR);
235
236	/* update irq data & counter */
237	if (status & RTC_ALM_BIT) {
238		events |= (RTC_AF | RTC_IRQF);
239		/* RTC alarm should be one-shot */
240		mxc_rtc_irq_enable(&pdev->dev, RTC_ALM_BIT, 0);
241	}
242
243	if (status & RTC_1HZ_BIT)
244		events |= (RTC_UF | RTC_IRQF);
245
246	if (status & PIT_ALL_ON)
247		events |= (RTC_PF | RTC_IRQF);
248
249	rtc_update_irq(pdata->rtc, 1, events);
250	spin_unlock_irqrestore(&pdata->rtc->irq_lock, flags);
251
252	return IRQ_HANDLED;
253}
254
255/*
256 * Clear all interrupts and release the IRQ
257 */
258static void mxc_rtc_release(struct device *dev)
259{
260	struct platform_device *pdev = to_platform_device(dev);
261	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
262	void __iomem *ioaddr = pdata->ioaddr;
263
264	spin_lock_irq(&pdata->rtc->irq_lock);
265
266	/* Disable all rtc interrupts */
267	writew(0, ioaddr + RTC_RTCIENR);
268
269	/* Clear all interrupt status */
270	writew(0xffffffff, ioaddr + RTC_RTCISR);
271
272	spin_unlock_irq(&pdata->rtc->irq_lock);
273}
274
275static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
276{
277	mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
278	return 0;
279}
280
281/*
282 * This function reads the current RTC time into tm in Gregorian date.
283 */
284static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
285{
286	time64_t val;
287
288	/* Avoid roll-over from reading the different registers */
289	do {
290		val = get_alarm_or_time(dev, MXC_RTC_TIME);
291	} while (val != get_alarm_or_time(dev, MXC_RTC_TIME));
292
293	rtc_time64_to_tm(val, tm);
294
295	return 0;
296}
297
298/*
299 * This function sets the internal RTC time based on tm in Gregorian date.
300 */
301static int mxc_rtc_set_mmss(struct device *dev, time64_t time)
302{
303	struct platform_device *pdev = to_platform_device(dev);
304	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
305
306	/*
307	 * TTC_DAYR register is 9-bit in MX1 SoC, save time and day of year only
308	 */
309	if (is_imx1_rtc(pdata)) {
310		struct rtc_time tm;
311
312		rtc_time64_to_tm(time, &tm);
313		tm.tm_year = 70;
314		time = rtc_tm_to_time64(&tm);
315	}
316
317	/* Avoid roll-over from reading the different registers */
318	do {
319		set_alarm_or_time(dev, MXC_RTC_TIME, time);
320	} while (time != get_alarm_or_time(dev, MXC_RTC_TIME));
321
322	return 0;
323}
324
325/*
326 * This function reads the current alarm value into the passed in 'alrm'
327 * argument. It updates the alrm's pending field value based on the whether
328 * an alarm interrupt occurs or not.
329 */
330static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
331{
332	struct platform_device *pdev = to_platform_device(dev);
333	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
334	void __iomem *ioaddr = pdata->ioaddr;
335
336	rtc_time64_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
337	alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;
338
339	return 0;
340}
341
342/*
343 * This function sets the RTC alarm based on passed in alrm.
344 */
345static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
346{
347	struct platform_device *pdev = to_platform_device(dev);
348	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
349
350	rtc_update_alarm(dev, &alrm->time);
351
352	memcpy(&pdata->g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
353	mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
354
355	return 0;
356}
357
358/* RTC layer */
359static struct rtc_class_ops mxc_rtc_ops = {
360	.release		= mxc_rtc_release,
361	.read_time		= mxc_rtc_read_time,
362	.set_mmss64		= mxc_rtc_set_mmss,
363	.read_alarm		= mxc_rtc_read_alarm,
364	.set_alarm		= mxc_rtc_set_alarm,
365	.alarm_irq_enable	= mxc_rtc_alarm_irq_enable,
366};
367
368static int mxc_rtc_probe(struct platform_device *pdev)
369{
370	struct resource *res;
371	struct rtc_device *rtc;
372	struct rtc_plat_data *pdata = NULL;
373	u32 reg;
374	unsigned long rate;
375	int ret;
376	const struct of_device_id *of_id;
377
378	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
379	if (!pdata)
380		return -ENOMEM;
381
382	of_id = of_match_device(imx_rtc_dt_ids, &pdev->dev);
383	if (of_id)
384		pdata->devtype = (enum imx_rtc_type)of_id->data;
385	else
386		pdata->devtype = pdev->id_entry->driver_data;
387
388	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
389	pdata->ioaddr = devm_ioremap_resource(&pdev->dev, res);
390	if (IS_ERR(pdata->ioaddr))
391		return PTR_ERR(pdata->ioaddr);
392
393	pdata->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
394	if (IS_ERR(pdata->clk_ipg)) {
395		dev_err(&pdev->dev, "unable to get ipg clock!\n");
396		return PTR_ERR(pdata->clk_ipg);
397	}
398
399	ret = clk_prepare_enable(pdata->clk_ipg);
400	if (ret)
401		return ret;
402
403	pdata->clk_ref = devm_clk_get(&pdev->dev, "ref");
404	if (IS_ERR(pdata->clk_ref)) {
405		dev_err(&pdev->dev, "unable to get ref clock!\n");
406		ret = PTR_ERR(pdata->clk_ref);
407		goto exit_put_clk_ipg;
408	}
409
410	ret = clk_prepare_enable(pdata->clk_ref);
411	if (ret)
412		goto exit_put_clk_ipg;
413
414	rate = clk_get_rate(pdata->clk_ref);
415
416	if (rate == 32768)
417		reg = RTC_INPUT_CLK_32768HZ;
418	else if (rate == 32000)
419		reg = RTC_INPUT_CLK_32000HZ;
420	else if (rate == 38400)
421		reg = RTC_INPUT_CLK_38400HZ;
422	else {
423		dev_err(&pdev->dev, "rtc clock is not valid (%lu)\n", rate);
424		ret = -EINVAL;
425		goto exit_put_clk_ref;
426	}
427
428	reg |= RTC_ENABLE_BIT;
429	writew(reg, (pdata->ioaddr + RTC_RTCCTL));
430	if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) {
431		dev_err(&pdev->dev, "hardware module can't be enabled!\n");
432		ret = -EIO;
433		goto exit_put_clk_ref;
434	}
435
436	platform_set_drvdata(pdev, pdata);
437
438	/* Configure and enable the RTC */
439	pdata->irq = platform_get_irq(pdev, 0);
440
441	if (pdata->irq >= 0 &&
442	    devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
443			     IRQF_SHARED, pdev->name, pdev) < 0) {
444		dev_warn(&pdev->dev, "interrupt not available.\n");
445		pdata->irq = -1;
446	}
447
448	if (pdata->irq >= 0)
449		device_init_wakeup(&pdev->dev, 1);
450
451	rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &mxc_rtc_ops,
452				  THIS_MODULE);
453	if (IS_ERR(rtc)) {
454		ret = PTR_ERR(rtc);
455		goto exit_put_clk_ref;
456	}
457
458	pdata->rtc = rtc;
459
460	return 0;
461
462exit_put_clk_ref:
463	clk_disable_unprepare(pdata->clk_ref);
464exit_put_clk_ipg:
465	clk_disable_unprepare(pdata->clk_ipg);
466
467	return ret;
468}
469
470static int mxc_rtc_remove(struct platform_device *pdev)
471{
472	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
473
474	clk_disable_unprepare(pdata->clk_ref);
475	clk_disable_unprepare(pdata->clk_ipg);
476
477	return 0;
478}
479
480#ifdef CONFIG_PM_SLEEP
481static int mxc_rtc_suspend(struct device *dev)
482{
483	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
484
485	if (device_may_wakeup(dev))
486		enable_irq_wake(pdata->irq);
487
488	return 0;
489}
490
491static int mxc_rtc_resume(struct device *dev)
492{
493	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
494
495	if (device_may_wakeup(dev))
496		disable_irq_wake(pdata->irq);
497
498	return 0;
499}
500#endif
501
502static SIMPLE_DEV_PM_OPS(mxc_rtc_pm_ops, mxc_rtc_suspend, mxc_rtc_resume);
503
504static struct platform_driver mxc_rtc_driver = {
505	.driver = {
506		   .name	= "mxc_rtc",
507		   .of_match_table = of_match_ptr(imx_rtc_dt_ids),
508		   .pm		= &mxc_rtc_pm_ops,
509	},
510	.id_table = imx_rtc_devtype,
511	.probe = mxc_rtc_probe,
512	.remove = mxc_rtc_remove,
513};
514
515module_platform_driver(mxc_rtc_driver)
516
517MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
518MODULE_DESCRIPTION("RTC driver for Freescale MXC");
519MODULE_LICENSE("GPL");
520
v4.17
  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#include <linux/of.h>
 20#include <linux/of_device.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
 
 
 
 
 
 
 
 
 
 
 
 46
 47#define MXC_RTC_TIME	0
 48#define MXC_RTC_ALARM	1
 49
 50#define RTC_HOURMIN	0x00	/*  32bit rtc hour/min counter reg */
 51#define RTC_SECOND	0x04	/*  32bit rtc seconds counter reg */
 52#define RTC_ALRM_HM	0x08	/*  32bit rtc alarm hour/min reg */
 53#define RTC_ALRM_SEC	0x0C	/*  32bit rtc alarm seconds reg */
 54#define RTC_RTCCTL	0x10	/*  32bit rtc control reg */
 55#define RTC_RTCISR	0x14	/*  32bit rtc interrupt status reg */
 56#define RTC_RTCIENR	0x18	/*  32bit rtc interrupt enable reg */
 57#define RTC_STPWCH	0x1C	/*  32bit rtc stopwatch min reg */
 58#define RTC_DAYR	0x20	/*  32bit rtc days counter reg */
 59#define RTC_DAYALARM	0x24	/*  32bit rtc day alarm reg */
 60#define RTC_TEST1	0x28	/*  32bit rtc test reg 1 */
 61#define RTC_TEST2	0x2C	/*  32bit rtc test reg 2 */
 62#define RTC_TEST3	0x30	/*  32bit rtc test reg 3 */
 63
 64enum imx_rtc_type {
 65	IMX1_RTC,
 66	IMX21_RTC,
 67};
 68
 69struct rtc_plat_data {
 70	struct rtc_device *rtc;
 71	void __iomem *ioaddr;
 72	int irq;
 73	struct clk *clk_ref;
 74	struct clk *clk_ipg;
 75	struct rtc_time g_rtc_alarm;
 76	enum imx_rtc_type devtype;
 77};
 78
 79static const struct platform_device_id imx_rtc_devtype[] = {
 80	{
 81		.name = "imx1-rtc",
 82		.driver_data = IMX1_RTC,
 83	}, {
 84		.name = "imx21-rtc",
 85		.driver_data = IMX21_RTC,
 86	}, {
 87		/* sentinel */
 88	}
 89};
 90MODULE_DEVICE_TABLE(platform, imx_rtc_devtype);
 91
 92#ifdef CONFIG_OF
 93static const struct of_device_id imx_rtc_dt_ids[] = {
 94	{ .compatible = "fsl,imx1-rtc", .data = (const void *)IMX1_RTC },
 95	{ .compatible = "fsl,imx21-rtc", .data = (const void *)IMX21_RTC },
 96	{}
 97};
 98MODULE_DEVICE_TABLE(of, imx_rtc_dt_ids);
 99#endif
100
101static inline int is_imx1_rtc(struct rtc_plat_data *data)
102{
103	return data->devtype == IMX1_RTC;
104}
105
106/*
107 * This function is used to obtain the RTC time or the alarm value in
108 * second.
109 */
110static time64_t get_alarm_or_time(struct device *dev, int time_alarm)
111{
112	struct platform_device *pdev = to_platform_device(dev);
113	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
114	void __iomem *ioaddr = pdata->ioaddr;
115	u32 day = 0, hr = 0, min = 0, sec = 0, hr_min = 0;
116
117	switch (time_alarm) {
118	case MXC_RTC_TIME:
119		day = readw(ioaddr + RTC_DAYR);
120		hr_min = readw(ioaddr + RTC_HOURMIN);
121		sec = readw(ioaddr + RTC_SECOND);
122		break;
123	case MXC_RTC_ALARM:
124		day = readw(ioaddr + RTC_DAYALARM);
125		hr_min = readw(ioaddr + RTC_ALRM_HM) & 0xffff;
126		sec = readw(ioaddr + RTC_ALRM_SEC);
127		break;
128	}
129
130	hr = hr_min >> 8;
131	min = hr_min & 0xff;
132
133	return ((((time64_t)day * 24 + hr) * 60) + min) * 60 + sec;
134}
135
136/*
137 * This function sets the RTC alarm value or the time value.
138 */
139static void set_alarm_or_time(struct device *dev, int time_alarm, time64_t time)
140{
141	u32 tod, day, hr, min, sec, temp;
142	struct platform_device *pdev = to_platform_device(dev);
143	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
144	void __iomem *ioaddr = pdata->ioaddr;
145
146	day = div_s64_rem(time, 86400, &tod);
147
148	/* time is within a day now */
149	hr = tod / 3600;
150	tod -= hr * 3600;
151
152	/* time is within an hour now */
153	min = tod / 60;
154	sec = tod - min * 60;
155
156	temp = (hr << 8) + min;
157
158	switch (time_alarm) {
159	case MXC_RTC_TIME:
160		writew(day, ioaddr + RTC_DAYR);
161		writew(sec, ioaddr + RTC_SECOND);
162		writew(temp, ioaddr + RTC_HOURMIN);
163		break;
164	case MXC_RTC_ALARM:
165		writew(day, ioaddr + RTC_DAYALARM);
166		writew(sec, ioaddr + RTC_ALRM_SEC);
167		writew(temp, ioaddr + RTC_ALRM_HM);
168		break;
169	}
170}
171
172/*
173 * This function updates the RTC alarm registers and then clears all the
174 * interrupt status bits.
175 */
176static void rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
177{
178	time64_t time;
179	struct platform_device *pdev = to_platform_device(dev);
180	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
181	void __iomem *ioaddr = pdata->ioaddr;
182
183	time = rtc_tm_to_time64(alrm);
184
185	/* clear all the interrupt status bits */
186	writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
187	set_alarm_or_time(dev, MXC_RTC_ALARM, time);
188}
189
190static void mxc_rtc_irq_enable(struct device *dev, unsigned int bit,
191				unsigned int enabled)
192{
193	struct platform_device *pdev = to_platform_device(dev);
194	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
195	void __iomem *ioaddr = pdata->ioaddr;
196	u32 reg;
197
198	spin_lock_irq(&pdata->rtc->irq_lock);
199	reg = readw(ioaddr + RTC_RTCIENR);
200
201	if (enabled)
202		reg |= bit;
203	else
204		reg &= ~bit;
205
206	writew(reg, ioaddr + RTC_RTCIENR);
207	spin_unlock_irq(&pdata->rtc->irq_lock);
208}
209
210/* This function is the RTC interrupt service routine. */
211static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
212{
213	struct platform_device *pdev = dev_id;
214	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
215	void __iomem *ioaddr = pdata->ioaddr;
216	unsigned long flags;
217	u32 status;
218	u32 events = 0;
219
220	spin_lock_irqsave(&pdata->rtc->irq_lock, flags);
221	status = readw(ioaddr + RTC_RTCISR) & readw(ioaddr + RTC_RTCIENR);
222	/* clear interrupt sources */
223	writew(status, ioaddr + RTC_RTCISR);
224
225	/* update irq data & counter */
226	if (status & RTC_ALM_BIT) {
227		events |= (RTC_AF | RTC_IRQF);
228		/* RTC alarm should be one-shot */
229		mxc_rtc_irq_enable(&pdev->dev, RTC_ALM_BIT, 0);
230	}
231
 
 
 
232	if (status & PIT_ALL_ON)
233		events |= (RTC_PF | RTC_IRQF);
234
235	rtc_update_irq(pdata->rtc, 1, events);
236	spin_unlock_irqrestore(&pdata->rtc->irq_lock, flags);
237
238	return IRQ_HANDLED;
239}
240
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
241static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
242{
243	mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
244	return 0;
245}
246
247/*
248 * This function reads the current RTC time into tm in Gregorian date.
249 */
250static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
251{
252	time64_t val;
253
254	/* Avoid roll-over from reading the different registers */
255	do {
256		val = get_alarm_or_time(dev, MXC_RTC_TIME);
257	} while (val != get_alarm_or_time(dev, MXC_RTC_TIME));
258
259	rtc_time64_to_tm(val, tm);
260
261	return 0;
262}
263
264/*
265 * This function sets the internal RTC time based on tm in Gregorian date.
266 */
267static int mxc_rtc_set_mmss(struct device *dev, time64_t time)
268{
269	struct platform_device *pdev = to_platform_device(dev);
270	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
271
272	/*
273	 * TTC_DAYR register is 9-bit in MX1 SoC, save time and day of year only
274	 */
275	if (is_imx1_rtc(pdata)) {
276		struct rtc_time tm;
277
278		rtc_time64_to_tm(time, &tm);
279		tm.tm_year = 70;
280		time = rtc_tm_to_time64(&tm);
281	}
282
283	/* Avoid roll-over from reading the different registers */
284	do {
285		set_alarm_or_time(dev, MXC_RTC_TIME, time);
286	} while (time != get_alarm_or_time(dev, MXC_RTC_TIME));
287
288	return 0;
289}
290
291/*
292 * This function reads the current alarm value into the passed in 'alrm'
293 * argument. It updates the alrm's pending field value based on the whether
294 * an alarm interrupt occurs or not.
295 */
296static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
297{
298	struct platform_device *pdev = to_platform_device(dev);
299	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
300	void __iomem *ioaddr = pdata->ioaddr;
301
302	rtc_time64_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
303	alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;
304
305	return 0;
306}
307
308/*
309 * This function sets the RTC alarm based on passed in alrm.
310 */
311static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
312{
313	struct platform_device *pdev = to_platform_device(dev);
314	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
315
316	rtc_update_alarm(dev, &alrm->time);
317
318	memcpy(&pdata->g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
319	mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
320
321	return 0;
322}
323
324/* RTC layer */
325static const struct rtc_class_ops mxc_rtc_ops = {
 
326	.read_time		= mxc_rtc_read_time,
327	.set_mmss64		= mxc_rtc_set_mmss,
328	.read_alarm		= mxc_rtc_read_alarm,
329	.set_alarm		= mxc_rtc_set_alarm,
330	.alarm_irq_enable	= mxc_rtc_alarm_irq_enable,
331};
332
333static int mxc_rtc_probe(struct platform_device *pdev)
334{
335	struct resource *res;
336	struct rtc_device *rtc;
337	struct rtc_plat_data *pdata = NULL;
338	u32 reg;
339	unsigned long rate;
340	int ret;
341	const struct of_device_id *of_id;
342
343	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
344	if (!pdata)
345		return -ENOMEM;
346
347	of_id = of_match_device(imx_rtc_dt_ids, &pdev->dev);
348	if (of_id)
349		pdata->devtype = (enum imx_rtc_type)of_id->data;
350	else
351		pdata->devtype = pdev->id_entry->driver_data;
352
353	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
354	pdata->ioaddr = devm_ioremap_resource(&pdev->dev, res);
355	if (IS_ERR(pdata->ioaddr))
356		return PTR_ERR(pdata->ioaddr);
357
358	pdata->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
359	if (IS_ERR(pdata->clk_ipg)) {
360		dev_err(&pdev->dev, "unable to get ipg clock!\n");
361		return PTR_ERR(pdata->clk_ipg);
362	}
363
364	ret = clk_prepare_enable(pdata->clk_ipg);
365	if (ret)
366		return ret;
367
368	pdata->clk_ref = devm_clk_get(&pdev->dev, "ref");
369	if (IS_ERR(pdata->clk_ref)) {
370		dev_err(&pdev->dev, "unable to get ref clock!\n");
371		ret = PTR_ERR(pdata->clk_ref);
372		goto exit_put_clk_ipg;
373	}
374
375	ret = clk_prepare_enable(pdata->clk_ref);
376	if (ret)
377		goto exit_put_clk_ipg;
378
379	rate = clk_get_rate(pdata->clk_ref);
380
381	if (rate == 32768)
382		reg = RTC_INPUT_CLK_32768HZ;
383	else if (rate == 32000)
384		reg = RTC_INPUT_CLK_32000HZ;
385	else if (rate == 38400)
386		reg = RTC_INPUT_CLK_38400HZ;
387	else {
388		dev_err(&pdev->dev, "rtc clock is not valid (%lu)\n", rate);
389		ret = -EINVAL;
390		goto exit_put_clk_ref;
391	}
392
393	reg |= RTC_ENABLE_BIT;
394	writew(reg, (pdata->ioaddr + RTC_RTCCTL));
395	if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) {
396		dev_err(&pdev->dev, "hardware module can't be enabled!\n");
397		ret = -EIO;
398		goto exit_put_clk_ref;
399	}
400
401	platform_set_drvdata(pdev, pdata);
402
403	/* Configure and enable the RTC */
404	pdata->irq = platform_get_irq(pdev, 0);
405
406	if (pdata->irq >= 0 &&
407	    devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
408			     IRQF_SHARED, pdev->name, pdev) < 0) {
409		dev_warn(&pdev->dev, "interrupt not available.\n");
410		pdata->irq = -1;
411	}
412
413	if (pdata->irq >= 0)
414		device_init_wakeup(&pdev->dev, 1);
415
416	rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &mxc_rtc_ops,
417				  THIS_MODULE);
418	if (IS_ERR(rtc)) {
419		ret = PTR_ERR(rtc);
420		goto exit_put_clk_ref;
421	}
422
423	pdata->rtc = rtc;
424
425	return 0;
426
427exit_put_clk_ref:
428	clk_disable_unprepare(pdata->clk_ref);
429exit_put_clk_ipg:
430	clk_disable_unprepare(pdata->clk_ipg);
431
432	return ret;
433}
434
435static int mxc_rtc_remove(struct platform_device *pdev)
436{
437	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
438
439	clk_disable_unprepare(pdata->clk_ref);
440	clk_disable_unprepare(pdata->clk_ipg);
441
442	return 0;
443}
444
445#ifdef CONFIG_PM_SLEEP
446static int mxc_rtc_suspend(struct device *dev)
447{
448	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
449
450	if (device_may_wakeup(dev))
451		enable_irq_wake(pdata->irq);
452
453	return 0;
454}
455
456static int mxc_rtc_resume(struct device *dev)
457{
458	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
459
460	if (device_may_wakeup(dev))
461		disable_irq_wake(pdata->irq);
462
463	return 0;
464}
465#endif
466
467static SIMPLE_DEV_PM_OPS(mxc_rtc_pm_ops, mxc_rtc_suspend, mxc_rtc_resume);
468
469static struct platform_driver mxc_rtc_driver = {
470	.driver = {
471		   .name	= "mxc_rtc",
472		   .of_match_table = of_match_ptr(imx_rtc_dt_ids),
473		   .pm		= &mxc_rtc_pm_ops,
474	},
475	.id_table = imx_rtc_devtype,
476	.probe = mxc_rtc_probe,
477	.remove = mxc_rtc_remove,
478};
479
480module_platform_driver(mxc_rtc_driver)
481
482MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
483MODULE_DESCRIPTION("RTC driver for Freescale MXC");
484MODULE_LICENSE("GPL");
485