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v5.9
  1// SPDX-License-Identifier: GPL-2.0+
  2//
  3// Copyright (C) 2011-2012 Freescale Semiconductor, Inc.
  4
  5#include <linux/init.h>
  6#include <linux/io.h>
  7#include <linux/kernel.h>
  8#include <linux/module.h>
  9#include <linux/of.h>
 
 10#include <linux/platform_device.h>
 11#include <linux/pm_wakeirq.h>
 12#include <linux/rtc.h>
 13#include <linux/clk.h>
 14#include <linux/mfd/syscon.h>
 15#include <linux/regmap.h>
 16
 17#define SNVS_LPREGISTER_OFFSET	0x34
 18
 19/* These register offsets are relative to LP (Low Power) range */
 20#define SNVS_LPCR		0x04
 21#define SNVS_LPSR		0x18
 22#define SNVS_LPSRTCMR		0x1c
 23#define SNVS_LPSRTCLR		0x20
 24#define SNVS_LPTAR		0x24
 25#define SNVS_LPPGDR		0x30
 26
 27#define SNVS_LPCR_SRTC_ENV	(1 << 0)
 28#define SNVS_LPCR_LPTA_EN	(1 << 1)
 29#define SNVS_LPCR_LPWUI_EN	(1 << 3)
 30#define SNVS_LPSR_LPTA		(1 << 0)
 31
 32#define SNVS_LPPGDR_INIT	0x41736166
 33#define CNTR_TO_SECS_SH		15
 34
 35struct snvs_rtc_data {
 36	struct rtc_device *rtc;
 37	struct regmap *regmap;
 38	int offset;
 39	int irq;
 40	struct clk *clk;
 41};
 42
 43/* Read 64 bit timer register, which could be in inconsistent state */
 44static u64 rtc_read_lpsrt(struct snvs_rtc_data *data)
 45{
 46	u32 msb, lsb;
 47
 48	regmap_read(data->regmap, data->offset + SNVS_LPSRTCMR, &msb);
 49	regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &lsb);
 50	return (u64)msb << 32 | lsb;
 51}
 52
 53/* Read the secure real time counter, taking care to deal with the cases of the
 54 * counter updating while being read.
 55 */
 56static u32 rtc_read_lp_counter(struct snvs_rtc_data *data)
 57{
 58	u64 read1, read2;
 59	unsigned int timeout = 100;
 60
 61	/* As expected, the registers might update between the read of the LSB
 62	 * reg and the MSB reg.  It's also possible that one register might be
 63	 * in partially modified state as well.
 64	 */
 65	read1 = rtc_read_lpsrt(data);
 66	do {
 67		read2 = read1;
 68		read1 = rtc_read_lpsrt(data);
 69	} while (read1 != read2 && --timeout);
 70	if (!timeout)
 71		dev_err(&data->rtc->dev, "Timeout trying to get valid LPSRT Counter read\n");
 72
 73	/* Convert 47-bit counter to 32-bit raw second count */
 74	return (u32) (read1 >> CNTR_TO_SECS_SH);
 75}
 76
 77/* Just read the lsb from the counter, dealing with inconsistent state */
 78static int rtc_read_lp_counter_lsb(struct snvs_rtc_data *data, u32 *lsb)
 79{
 80	u32 count1, count2;
 81	unsigned int timeout = 100;
 82
 83	regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1);
 84	do {
 85		count2 = count1;
 86		regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1);
 87	} while (count1 != count2 && --timeout);
 88	if (!timeout) {
 89		dev_err(&data->rtc->dev, "Timeout trying to get valid LPSRT Counter read\n");
 90		return -ETIMEDOUT;
 91	}
 92
 93	*lsb = count1;
 94	return 0;
 95}
 96
 97static int rtc_write_sync_lp(struct snvs_rtc_data *data)
 98{
 99	u32 count1, count2;
100	u32 elapsed;
101	unsigned int timeout = 1000;
102	int ret;
103
104	ret = rtc_read_lp_counter_lsb(data, &count1);
105	if (ret)
106		return ret;
107
108	/* Wait for 3 CKIL cycles, about 61.0-91.5 µs */
109	do {
110		ret = rtc_read_lp_counter_lsb(data, &count2);
111		if (ret)
112			return ret;
113		elapsed = count2 - count1; /* wrap around _is_ handled! */
114	} while (elapsed < 3 && --timeout);
115	if (!timeout) {
116		dev_err(&data->rtc->dev, "Timeout waiting for LPSRT Counter to change\n");
117		return -ETIMEDOUT;
118	}
119	return 0;
120}
121
122static int snvs_rtc_enable(struct snvs_rtc_data *data, bool enable)
123{
124	int timeout = 1000;
125	u32 lpcr;
126
127	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_SRTC_ENV,
128			   enable ? SNVS_LPCR_SRTC_ENV : 0);
129
130	while (--timeout) {
131		regmap_read(data->regmap, data->offset + SNVS_LPCR, &lpcr);
132
133		if (enable) {
134			if (lpcr & SNVS_LPCR_SRTC_ENV)
135				break;
136		} else {
137			if (!(lpcr & SNVS_LPCR_SRTC_ENV))
138				break;
139		}
140	}
141
142	if (!timeout)
143		return -ETIMEDOUT;
144
145	return 0;
146}
147
148static int snvs_rtc_read_time(struct device *dev, struct rtc_time *tm)
149{
150	struct snvs_rtc_data *data = dev_get_drvdata(dev);
151	unsigned long time;
152	int ret;
153
154	if (data->clk) {
155		ret = clk_enable(data->clk);
156		if (ret)
157			return ret;
158	}
159
160	time = rtc_read_lp_counter(data);
161	rtc_time64_to_tm(time, tm);
162
163	if (data->clk)
164		clk_disable(data->clk);
165
166	return 0;
167}
168
169static int snvs_rtc_set_time(struct device *dev, struct rtc_time *tm)
170{
171	struct snvs_rtc_data *data = dev_get_drvdata(dev);
172	unsigned long time = rtc_tm_to_time64(tm);
173	int ret;
174
175	if (data->clk) {
176		ret = clk_enable(data->clk);
177		if (ret)
178			return ret;
179	}
180
181	/* Disable RTC first */
182	ret = snvs_rtc_enable(data, false);
183	if (ret)
184		return ret;
185
186	/* Write 32-bit time to 47-bit timer, leaving 15 LSBs blank */
187	regmap_write(data->regmap, data->offset + SNVS_LPSRTCLR, time << CNTR_TO_SECS_SH);
188	regmap_write(data->regmap, data->offset + SNVS_LPSRTCMR, time >> (32 - CNTR_TO_SECS_SH));
189
190	/* Enable RTC again */
191	ret = snvs_rtc_enable(data, true);
192
193	if (data->clk)
194		clk_disable(data->clk);
195
196	return ret;
197}
198
199static int snvs_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
200{
201	struct snvs_rtc_data *data = dev_get_drvdata(dev);
202	u32 lptar, lpsr;
203	int ret;
204
205	if (data->clk) {
206		ret = clk_enable(data->clk);
207		if (ret)
208			return ret;
209	}
210
211	regmap_read(data->regmap, data->offset + SNVS_LPTAR, &lptar);
212	rtc_time64_to_tm(lptar, &alrm->time);
213
214	regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
215	alrm->pending = (lpsr & SNVS_LPSR_LPTA) ? 1 : 0;
216
217	if (data->clk)
218		clk_disable(data->clk);
219
220	return 0;
221}
222
223static int snvs_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
224{
225	struct snvs_rtc_data *data = dev_get_drvdata(dev);
226	int ret;
227
228	if (data->clk) {
229		ret = clk_enable(data->clk);
230		if (ret)
231			return ret;
232	}
233
234	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR,
235			   (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN),
236			   enable ? (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN) : 0);
237
238	ret = rtc_write_sync_lp(data);
239
240	if (data->clk)
241		clk_disable(data->clk);
242
243	return ret;
244}
245
246static int snvs_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
247{
248	struct snvs_rtc_data *data = dev_get_drvdata(dev);
249	unsigned long time = rtc_tm_to_time64(&alrm->time);
250	int ret;
251
252	if (data->clk) {
253		ret = clk_enable(data->clk);
254		if (ret)
255			return ret;
256	}
257
258	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_LPTA_EN, 0);
259	ret = rtc_write_sync_lp(data);
260	if (ret)
261		return ret;
262	regmap_write(data->regmap, data->offset + SNVS_LPTAR, time);
263
264	/* Clear alarm interrupt status bit */
265	regmap_write(data->regmap, data->offset + SNVS_LPSR, SNVS_LPSR_LPTA);
266
267	if (data->clk)
268		clk_disable(data->clk);
269
270	return snvs_rtc_alarm_irq_enable(dev, alrm->enabled);
271}
272
273static const struct rtc_class_ops snvs_rtc_ops = {
274	.read_time = snvs_rtc_read_time,
275	.set_time = snvs_rtc_set_time,
276	.read_alarm = snvs_rtc_read_alarm,
277	.set_alarm = snvs_rtc_set_alarm,
278	.alarm_irq_enable = snvs_rtc_alarm_irq_enable,
279};
280
281static irqreturn_t snvs_rtc_irq_handler(int irq, void *dev_id)
282{
283	struct device *dev = dev_id;
284	struct snvs_rtc_data *data = dev_get_drvdata(dev);
285	u32 lpsr;
286	u32 events = 0;
287
288	if (data->clk)
289		clk_enable(data->clk);
290
291	regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
292
293	if (lpsr & SNVS_LPSR_LPTA) {
294		events |= (RTC_AF | RTC_IRQF);
295
296		/* RTC alarm should be one-shot */
297		snvs_rtc_alarm_irq_enable(dev, 0);
298
299		rtc_update_irq(data->rtc, 1, events);
300	}
301
302	/* clear interrupt status */
303	regmap_write(data->regmap, data->offset + SNVS_LPSR, lpsr);
304
305	if (data->clk)
306		clk_disable(data->clk);
307
308	return events ? IRQ_HANDLED : IRQ_NONE;
309}
310
311static const struct regmap_config snvs_rtc_config = {
312	.reg_bits = 32,
313	.val_bits = 32,
314	.reg_stride = 4,
315};
316
317static void snvs_rtc_action(void *data)
318{
319	if (data)
320		clk_disable_unprepare(data);
321}
322
323static int snvs_rtc_probe(struct platform_device *pdev)
324{
325	struct snvs_rtc_data *data;
326	int ret;
327	void __iomem *mmio;
328
329	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
330	if (!data)
331		return -ENOMEM;
332
333	data->rtc = devm_rtc_allocate_device(&pdev->dev);
334	if (IS_ERR(data->rtc))
335		return PTR_ERR(data->rtc);
336
337	data->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");
338
339	if (IS_ERR(data->regmap)) {
340		dev_warn(&pdev->dev, "snvs rtc: you use old dts file, please update it\n");
341
342		mmio = devm_platform_ioremap_resource(pdev, 0);
343		if (IS_ERR(mmio))
344			return PTR_ERR(mmio);
345
346		data->regmap = devm_regmap_init_mmio(&pdev->dev, mmio, &snvs_rtc_config);
347	} else {
348		data->offset = SNVS_LPREGISTER_OFFSET;
349		of_property_read_u32(pdev->dev.of_node, "offset", &data->offset);
350	}
351
352	if (IS_ERR(data->regmap)) {
353		dev_err(&pdev->dev, "Can't find snvs syscon\n");
354		return -ENODEV;
355	}
356
357	data->irq = platform_get_irq(pdev, 0);
358	if (data->irq < 0)
359		return data->irq;
360
361	data->clk = devm_clk_get(&pdev->dev, "snvs-rtc");
362	if (IS_ERR(data->clk)) {
363		data->clk = NULL;
364	} else {
365		ret = clk_prepare_enable(data->clk);
366		if (ret) {
367			dev_err(&pdev->dev,
368				"Could not prepare or enable the snvs clock\n");
369			return ret;
370		}
371	}
372
373	ret = devm_add_action_or_reset(&pdev->dev, snvs_rtc_action, data->clk);
374	if (ret)
375		return ret;
376
377	platform_set_drvdata(pdev, data);
378
379	/* Initialize glitch detect */
380	regmap_write(data->regmap, data->offset + SNVS_LPPGDR, SNVS_LPPGDR_INIT);
381
382	/* Clear interrupt status */
383	regmap_write(data->regmap, data->offset + SNVS_LPSR, 0xffffffff);
384
385	/* Enable RTC */
386	ret = snvs_rtc_enable(data, true);
387	if (ret) {
388		dev_err(&pdev->dev, "failed to enable rtc %d\n", ret);
389		return ret;
390	}
391
392	device_init_wakeup(&pdev->dev, true);
393	ret = dev_pm_set_wake_irq(&pdev->dev, data->irq);
394	if (ret)
395		dev_err(&pdev->dev, "failed to enable irq wake\n");
396
397	ret = devm_request_irq(&pdev->dev, data->irq, snvs_rtc_irq_handler,
398			       IRQF_SHARED, "rtc alarm", &pdev->dev);
399	if (ret) {
400		dev_err(&pdev->dev, "failed to request irq %d: %d\n",
401			data->irq, ret);
402		return ret;
403	}
404
405	data->rtc->ops = &snvs_rtc_ops;
406	data->rtc->range_max = U32_MAX;
 
 
 
 
 
 
 
407
408	return rtc_register_device(data->rtc);
 
 
 
 
409}
410
411static int __maybe_unused snvs_rtc_suspend_noirq(struct device *dev)
412{
413	struct snvs_rtc_data *data = dev_get_drvdata(dev);
414
415	if (data->clk)
416		clk_disable(data->clk);
417
418	return 0;
419}
420
421static int __maybe_unused snvs_rtc_resume_noirq(struct device *dev)
422{
423	struct snvs_rtc_data *data = dev_get_drvdata(dev);
424
425	if (data->clk)
426		return clk_enable(data->clk);
427
428	return 0;
429}
430
431static const struct dev_pm_ops snvs_rtc_pm_ops = {
432	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(snvs_rtc_suspend_noirq, snvs_rtc_resume_noirq)
433};
434
435static const struct of_device_id snvs_dt_ids[] = {
436	{ .compatible = "fsl,sec-v4.0-mon-rtc-lp", },
437	{ /* sentinel */ }
438};
439MODULE_DEVICE_TABLE(of, snvs_dt_ids);
440
441static struct platform_driver snvs_rtc_driver = {
442	.driver = {
443		.name	= "snvs_rtc",
444		.pm	= &snvs_rtc_pm_ops,
445		.of_match_table = snvs_dt_ids,
446	},
447	.probe		= snvs_rtc_probe,
448};
449module_platform_driver(snvs_rtc_driver);
450
451MODULE_AUTHOR("Freescale Semiconductor, Inc.");
452MODULE_DESCRIPTION("Freescale SNVS RTC Driver");
453MODULE_LICENSE("GPL");
v5.4
  1// SPDX-License-Identifier: GPL-2.0+
  2//
  3// Copyright (C) 2011-2012 Freescale Semiconductor, Inc.
  4
  5#include <linux/init.h>
  6#include <linux/io.h>
  7#include <linux/kernel.h>
  8#include <linux/module.h>
  9#include <linux/of.h>
 10#include <linux/of_device.h>
 11#include <linux/platform_device.h>
 12#include <linux/pm_wakeirq.h>
 13#include <linux/rtc.h>
 14#include <linux/clk.h>
 15#include <linux/mfd/syscon.h>
 16#include <linux/regmap.h>
 17
 18#define SNVS_LPREGISTER_OFFSET	0x34
 19
 20/* These register offsets are relative to LP (Low Power) range */
 21#define SNVS_LPCR		0x04
 22#define SNVS_LPSR		0x18
 23#define SNVS_LPSRTCMR		0x1c
 24#define SNVS_LPSRTCLR		0x20
 25#define SNVS_LPTAR		0x24
 26#define SNVS_LPPGDR		0x30
 27
 28#define SNVS_LPCR_SRTC_ENV	(1 << 0)
 29#define SNVS_LPCR_LPTA_EN	(1 << 1)
 30#define SNVS_LPCR_LPWUI_EN	(1 << 3)
 31#define SNVS_LPSR_LPTA		(1 << 0)
 32
 33#define SNVS_LPPGDR_INIT	0x41736166
 34#define CNTR_TO_SECS_SH		15
 35
 36struct snvs_rtc_data {
 37	struct rtc_device *rtc;
 38	struct regmap *regmap;
 39	int offset;
 40	int irq;
 41	struct clk *clk;
 42};
 43
 44/* Read 64 bit timer register, which could be in inconsistent state */
 45static u64 rtc_read_lpsrt(struct snvs_rtc_data *data)
 46{
 47	u32 msb, lsb;
 48
 49	regmap_read(data->regmap, data->offset + SNVS_LPSRTCMR, &msb);
 50	regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &lsb);
 51	return (u64)msb << 32 | lsb;
 52}
 53
 54/* Read the secure real time counter, taking care to deal with the cases of the
 55 * counter updating while being read.
 56 */
 57static u32 rtc_read_lp_counter(struct snvs_rtc_data *data)
 58{
 59	u64 read1, read2;
 60	unsigned int timeout = 100;
 61
 62	/* As expected, the registers might update between the read of the LSB
 63	 * reg and the MSB reg.  It's also possible that one register might be
 64	 * in partially modified state as well.
 65	 */
 66	read1 = rtc_read_lpsrt(data);
 67	do {
 68		read2 = read1;
 69		read1 = rtc_read_lpsrt(data);
 70	} while (read1 != read2 && --timeout);
 71	if (!timeout)
 72		dev_err(&data->rtc->dev, "Timeout trying to get valid LPSRT Counter read\n");
 73
 74	/* Convert 47-bit counter to 32-bit raw second count */
 75	return (u32) (read1 >> CNTR_TO_SECS_SH);
 76}
 77
 78/* Just read the lsb from the counter, dealing with inconsistent state */
 79static int rtc_read_lp_counter_lsb(struct snvs_rtc_data *data, u32 *lsb)
 80{
 81	u32 count1, count2;
 82	unsigned int timeout = 100;
 83
 84	regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1);
 85	do {
 86		count2 = count1;
 87		regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1);
 88	} while (count1 != count2 && --timeout);
 89	if (!timeout) {
 90		dev_err(&data->rtc->dev, "Timeout trying to get valid LPSRT Counter read\n");
 91		return -ETIMEDOUT;
 92	}
 93
 94	*lsb = count1;
 95	return 0;
 96}
 97
 98static int rtc_write_sync_lp(struct snvs_rtc_data *data)
 99{
100	u32 count1, count2;
101	u32 elapsed;
102	unsigned int timeout = 1000;
103	int ret;
104
105	ret = rtc_read_lp_counter_lsb(data, &count1);
106	if (ret)
107		return ret;
108
109	/* Wait for 3 CKIL cycles, about 61.0-91.5 µs */
110	do {
111		ret = rtc_read_lp_counter_lsb(data, &count2);
112		if (ret)
113			return ret;
114		elapsed = count2 - count1; /* wrap around _is_ handled! */
115	} while (elapsed < 3 && --timeout);
116	if (!timeout) {
117		dev_err(&data->rtc->dev, "Timeout waiting for LPSRT Counter to change\n");
118		return -ETIMEDOUT;
119	}
120	return 0;
121}
122
123static int snvs_rtc_enable(struct snvs_rtc_data *data, bool enable)
124{
125	int timeout = 1000;
126	u32 lpcr;
127
128	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_SRTC_ENV,
129			   enable ? SNVS_LPCR_SRTC_ENV : 0);
130
131	while (--timeout) {
132		regmap_read(data->regmap, data->offset + SNVS_LPCR, &lpcr);
133
134		if (enable) {
135			if (lpcr & SNVS_LPCR_SRTC_ENV)
136				break;
137		} else {
138			if (!(lpcr & SNVS_LPCR_SRTC_ENV))
139				break;
140		}
141	}
142
143	if (!timeout)
144		return -ETIMEDOUT;
145
146	return 0;
147}
148
149static int snvs_rtc_read_time(struct device *dev, struct rtc_time *tm)
150{
151	struct snvs_rtc_data *data = dev_get_drvdata(dev);
152	unsigned long time = rtc_read_lp_counter(data);
 
 
 
 
 
 
 
153
 
154	rtc_time64_to_tm(time, tm);
155
 
 
 
156	return 0;
157}
158
159static int snvs_rtc_set_time(struct device *dev, struct rtc_time *tm)
160{
161	struct snvs_rtc_data *data = dev_get_drvdata(dev);
162	unsigned long time = rtc_tm_to_time64(tm);
163	int ret;
164
 
 
 
 
 
 
165	/* Disable RTC first */
166	ret = snvs_rtc_enable(data, false);
167	if (ret)
168		return ret;
169
170	/* Write 32-bit time to 47-bit timer, leaving 15 LSBs blank */
171	regmap_write(data->regmap, data->offset + SNVS_LPSRTCLR, time << CNTR_TO_SECS_SH);
172	regmap_write(data->regmap, data->offset + SNVS_LPSRTCMR, time >> (32 - CNTR_TO_SECS_SH));
173
174	/* Enable RTC again */
175	ret = snvs_rtc_enable(data, true);
176
 
 
 
177	return ret;
178}
179
180static int snvs_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
181{
182	struct snvs_rtc_data *data = dev_get_drvdata(dev);
183	u32 lptar, lpsr;
 
 
 
 
 
 
 
184
185	regmap_read(data->regmap, data->offset + SNVS_LPTAR, &lptar);
186	rtc_time64_to_tm(lptar, &alrm->time);
187
188	regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
189	alrm->pending = (lpsr & SNVS_LPSR_LPTA) ? 1 : 0;
190
 
 
 
191	return 0;
192}
193
194static int snvs_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
195{
196	struct snvs_rtc_data *data = dev_get_drvdata(dev);
 
 
 
 
 
 
 
197
198	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR,
199			   (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN),
200			   enable ? (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN) : 0);
201
202	return rtc_write_sync_lp(data);
 
 
 
 
 
203}
204
205static int snvs_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
206{
207	struct snvs_rtc_data *data = dev_get_drvdata(dev);
208	unsigned long time = rtc_tm_to_time64(&alrm->time);
209	int ret;
210
 
 
 
 
 
 
211	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_LPTA_EN, 0);
212	ret = rtc_write_sync_lp(data);
213	if (ret)
214		return ret;
215	regmap_write(data->regmap, data->offset + SNVS_LPTAR, time);
216
217	/* Clear alarm interrupt status bit */
218	regmap_write(data->regmap, data->offset + SNVS_LPSR, SNVS_LPSR_LPTA);
219
 
 
 
220	return snvs_rtc_alarm_irq_enable(dev, alrm->enabled);
221}
222
223static const struct rtc_class_ops snvs_rtc_ops = {
224	.read_time = snvs_rtc_read_time,
225	.set_time = snvs_rtc_set_time,
226	.read_alarm = snvs_rtc_read_alarm,
227	.set_alarm = snvs_rtc_set_alarm,
228	.alarm_irq_enable = snvs_rtc_alarm_irq_enable,
229};
230
231static irqreturn_t snvs_rtc_irq_handler(int irq, void *dev_id)
232{
233	struct device *dev = dev_id;
234	struct snvs_rtc_data *data = dev_get_drvdata(dev);
235	u32 lpsr;
236	u32 events = 0;
237
238	if (data->clk)
239		clk_enable(data->clk);
240
241	regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
242
243	if (lpsr & SNVS_LPSR_LPTA) {
244		events |= (RTC_AF | RTC_IRQF);
245
246		/* RTC alarm should be one-shot */
247		snvs_rtc_alarm_irq_enable(dev, 0);
248
249		rtc_update_irq(data->rtc, 1, events);
250	}
251
252	/* clear interrupt status */
253	regmap_write(data->regmap, data->offset + SNVS_LPSR, lpsr);
254
255	if (data->clk)
256		clk_disable(data->clk);
257
258	return events ? IRQ_HANDLED : IRQ_NONE;
259}
260
261static const struct regmap_config snvs_rtc_config = {
262	.reg_bits = 32,
263	.val_bits = 32,
264	.reg_stride = 4,
265};
266
 
 
 
 
 
 
267static int snvs_rtc_probe(struct platform_device *pdev)
268{
269	struct snvs_rtc_data *data;
270	int ret;
271	void __iomem *mmio;
272
273	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
274	if (!data)
275		return -ENOMEM;
276
277	data->rtc = devm_rtc_allocate_device(&pdev->dev);
278	if (IS_ERR(data->rtc))
279		return PTR_ERR(data->rtc);
280
281	data->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");
282
283	if (IS_ERR(data->regmap)) {
284		dev_warn(&pdev->dev, "snvs rtc: you use old dts file, please update it\n");
285
286		mmio = devm_platform_ioremap_resource(pdev, 0);
287		if (IS_ERR(mmio))
288			return PTR_ERR(mmio);
289
290		data->regmap = devm_regmap_init_mmio(&pdev->dev, mmio, &snvs_rtc_config);
291	} else {
292		data->offset = SNVS_LPREGISTER_OFFSET;
293		of_property_read_u32(pdev->dev.of_node, "offset", &data->offset);
294	}
295
296	if (IS_ERR(data->regmap)) {
297		dev_err(&pdev->dev, "Can't find snvs syscon\n");
298		return -ENODEV;
299	}
300
301	data->irq = platform_get_irq(pdev, 0);
302	if (data->irq < 0)
303		return data->irq;
304
305	data->clk = devm_clk_get(&pdev->dev, "snvs-rtc");
306	if (IS_ERR(data->clk)) {
307		data->clk = NULL;
308	} else {
309		ret = clk_prepare_enable(data->clk);
310		if (ret) {
311			dev_err(&pdev->dev,
312				"Could not prepare or enable the snvs clock\n");
313			return ret;
314		}
315	}
316
 
 
 
 
317	platform_set_drvdata(pdev, data);
318
319	/* Initialize glitch detect */
320	regmap_write(data->regmap, data->offset + SNVS_LPPGDR, SNVS_LPPGDR_INIT);
321
322	/* Clear interrupt status */
323	regmap_write(data->regmap, data->offset + SNVS_LPSR, 0xffffffff);
324
325	/* Enable RTC */
326	ret = snvs_rtc_enable(data, true);
327	if (ret) {
328		dev_err(&pdev->dev, "failed to enable rtc %d\n", ret);
329		goto error_rtc_device_register;
330	}
331
332	device_init_wakeup(&pdev->dev, true);
333	ret = dev_pm_set_wake_irq(&pdev->dev, data->irq);
334	if (ret)
335		dev_err(&pdev->dev, "failed to enable irq wake\n");
336
337	ret = devm_request_irq(&pdev->dev, data->irq, snvs_rtc_irq_handler,
338			       IRQF_SHARED, "rtc alarm", &pdev->dev);
339	if (ret) {
340		dev_err(&pdev->dev, "failed to request irq %d: %d\n",
341			data->irq, ret);
342		goto error_rtc_device_register;
343	}
344
345	data->rtc->ops = &snvs_rtc_ops;
346	data->rtc->range_max = U32_MAX;
347	ret = rtc_register_device(data->rtc);
348	if (ret) {
349		dev_err(&pdev->dev, "failed to register rtc: %d\n", ret);
350		goto error_rtc_device_register;
351	}
352
353	return 0;
354
355error_rtc_device_register:
356	if (data->clk)
357		clk_disable_unprepare(data->clk);
358
359	return ret;
360}
361
362static int __maybe_unused snvs_rtc_suspend_noirq(struct device *dev)
363{
364	struct snvs_rtc_data *data = dev_get_drvdata(dev);
365
366	if (data->clk)
367		clk_disable_unprepare(data->clk);
368
369	return 0;
370}
371
372static int __maybe_unused snvs_rtc_resume_noirq(struct device *dev)
373{
374	struct snvs_rtc_data *data = dev_get_drvdata(dev);
375
376	if (data->clk)
377		return clk_prepare_enable(data->clk);
378
379	return 0;
380}
381
382static const struct dev_pm_ops snvs_rtc_pm_ops = {
383	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(snvs_rtc_suspend_noirq, snvs_rtc_resume_noirq)
384};
385
386static const struct of_device_id snvs_dt_ids[] = {
387	{ .compatible = "fsl,sec-v4.0-mon-rtc-lp", },
388	{ /* sentinel */ }
389};
390MODULE_DEVICE_TABLE(of, snvs_dt_ids);
391
392static struct platform_driver snvs_rtc_driver = {
393	.driver = {
394		.name	= "snvs_rtc",
395		.pm	= &snvs_rtc_pm_ops,
396		.of_match_table = snvs_dt_ids,
397	},
398	.probe		= snvs_rtc_probe,
399};
400module_platform_driver(snvs_rtc_driver);
401
402MODULE_AUTHOR("Freescale Semiconductor, Inc.");
403MODULE_DESCRIPTION("Freescale SNVS RTC Driver");
404MODULE_LICENSE("GPL");