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v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
  3 */
  4#include <linux/of.h>
  5#include <linux/module.h>
  6#include <linux/init.h>
  7#include <linux/rtc.h>
  8#include <linux/platform_device.h>
  9#include <linux/pm.h>
 10#include <linux/pm_wakeirq.h>
 11#include <linux/regmap.h>
 12#include <linux/slab.h>
 13#include <linux/spinlock.h>
 14
 15/* RTC Register offsets from RTC CTRL REG */
 16#define PM8XXX_ALARM_CTRL_OFFSET	0x01
 17#define PM8XXX_RTC_WRITE_OFFSET		0x02
 18#define PM8XXX_RTC_READ_OFFSET		0x06
 19#define PM8XXX_ALARM_RW_OFFSET		0x0A
 20
 21/* RTC_CTRL register bit fields */
 22#define PM8xxx_RTC_ENABLE		BIT(7)
 23#define PM8xxx_RTC_ALARM_CLEAR		BIT(0)
 24#define PM8xxx_RTC_ALARM_ENABLE		BIT(7)
 25
 26#define NUM_8_BIT_RTC_REGS		0x4
 27
 28/**
 29 * struct pm8xxx_rtc_regs - describe RTC registers per PMIC versions
 30 * @ctrl: base address of control register
 31 * @write: base address of write register
 32 * @read: base address of read register
 33 * @alarm_ctrl: base address of alarm control register
 34 * @alarm_ctrl2: base address of alarm control2 register
 35 * @alarm_rw: base address of alarm read-write register
 36 * @alarm_en: alarm enable mask
 37 */
 38struct pm8xxx_rtc_regs {
 39	unsigned int ctrl;
 40	unsigned int write;
 41	unsigned int read;
 42	unsigned int alarm_ctrl;
 43	unsigned int alarm_ctrl2;
 44	unsigned int alarm_rw;
 45	unsigned int alarm_en;
 46};
 47
 48/**
 49 * struct pm8xxx_rtc -  rtc driver internal structure
 50 * @rtc:		rtc device for this driver.
 51 * @regmap:		regmap used to access RTC registers
 52 * @allow_set_time:	indicates whether writing to the RTC is allowed
 53 * @rtc_alarm_irq:	rtc alarm irq number.
 54 * @regs:		rtc registers description.
 55 * @rtc_dev:		device structure.
 56 * @ctrl_reg_lock:	spinlock protecting access to ctrl_reg.
 57 */
 58struct pm8xxx_rtc {
 59	struct rtc_device *rtc;
 60	struct regmap *regmap;
 61	bool allow_set_time;
 62	int rtc_alarm_irq;
 63	const struct pm8xxx_rtc_regs *regs;
 64	struct device *rtc_dev;
 65	spinlock_t ctrl_reg_lock;
 66};
 67
 68/*
 69 * Steps to write the RTC registers.
 70 * 1. Disable alarm if enabled.
 71 * 2. Disable rtc if enabled.
 72 * 3. Write 0x00 to LSB.
 73 * 4. Write Byte[1], Byte[2], Byte[3] then Byte[0].
 74 * 5. Enable rtc if disabled in step 2.
 75 * 6. Enable alarm if disabled in step 1.
 76 */
 77static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
 78{
 79	int rc, i;
 80	unsigned long secs, irq_flags;
 81	u8 value[NUM_8_BIT_RTC_REGS], alarm_enabled = 0, rtc_disabled = 0;
 82	unsigned int ctrl_reg, rtc_ctrl_reg;
 83	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
 84	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
 85
 86	if (!rtc_dd->allow_set_time)
 87		return -ENODEV;
 88
 89	secs = rtc_tm_to_time64(tm);
 90
 91	dev_dbg(dev, "Seconds value to be written to RTC = %lu\n", secs);
 92
 93	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
 94		value[i] = secs & 0xFF;
 95		secs >>= 8;
 96	}
 97
 98	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
 99
100	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
101	if (rc)
102		goto rtc_rw_fail;
103
104	if (ctrl_reg & regs->alarm_en) {
105		alarm_enabled = 1;
106		ctrl_reg &= ~regs->alarm_en;
107		rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
108		if (rc) {
109			dev_err(dev, "Write to RTC Alarm control register failed\n");
110			goto rtc_rw_fail;
111		}
112	}
113
114	/* Disable RTC H/w before writing on RTC register */
115	rc = regmap_read(rtc_dd->regmap, regs->ctrl, &rtc_ctrl_reg);
116	if (rc)
117		goto rtc_rw_fail;
118
119	if (rtc_ctrl_reg & PM8xxx_RTC_ENABLE) {
120		rtc_disabled = 1;
121		rtc_ctrl_reg &= ~PM8xxx_RTC_ENABLE;
122		rc = regmap_write(rtc_dd->regmap, regs->ctrl, rtc_ctrl_reg);
123		if (rc) {
124			dev_err(dev, "Write to RTC control register failed\n");
125			goto rtc_rw_fail;
126		}
127	}
128
129	/* Write 0 to Byte[0] */
130	rc = regmap_write(rtc_dd->regmap, regs->write, 0);
131	if (rc) {
132		dev_err(dev, "Write to RTC write data register failed\n");
133		goto rtc_rw_fail;
134	}
135
136	/* Write Byte[1], Byte[2], Byte[3] */
137	rc = regmap_bulk_write(rtc_dd->regmap, regs->write + 1,
138			       &value[1], sizeof(value) - 1);
139	if (rc) {
140		dev_err(dev, "Write to RTC write data register failed\n");
141		goto rtc_rw_fail;
142	}
143
144	/* Write Byte[0] */
145	rc = regmap_write(rtc_dd->regmap, regs->write, value[0]);
146	if (rc) {
147		dev_err(dev, "Write to RTC write data register failed\n");
148		goto rtc_rw_fail;
149	}
150
151	/* Enable RTC H/w after writing on RTC register */
152	if (rtc_disabled) {
153		rtc_ctrl_reg |= PM8xxx_RTC_ENABLE;
154		rc = regmap_write(rtc_dd->regmap, regs->ctrl, rtc_ctrl_reg);
155		if (rc) {
156			dev_err(dev, "Write to RTC control register failed\n");
157			goto rtc_rw_fail;
158		}
159	}
160
161	if (alarm_enabled) {
162		ctrl_reg |= regs->alarm_en;
163		rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
164		if (rc) {
165			dev_err(dev, "Write to RTC Alarm control register failed\n");
166			goto rtc_rw_fail;
167		}
168	}
169
170rtc_rw_fail:
171	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
172
173	return rc;
174}
175
176static int pm8xxx_rtc_read_time(struct device *dev, struct rtc_time *tm)
177{
178	int rc;
179	u8 value[NUM_8_BIT_RTC_REGS];
180	unsigned long secs;
181	unsigned int reg;
182	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
183	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
184
185	rc = regmap_bulk_read(rtc_dd->regmap, regs->read, value, sizeof(value));
186	if (rc) {
187		dev_err(dev, "RTC read data register failed\n");
188		return rc;
189	}
190
191	/*
192	 * Read the LSB again and check if there has been a carry over.
193	 * If there is, redo the read operation.
194	 */
195	rc = regmap_read(rtc_dd->regmap, regs->read, &reg);
196	if (rc < 0) {
197		dev_err(dev, "RTC read data register failed\n");
198		return rc;
199	}
200
201	if (unlikely(reg < value[0])) {
202		rc = regmap_bulk_read(rtc_dd->regmap, regs->read,
203				      value, sizeof(value));
204		if (rc) {
205			dev_err(dev, "RTC read data register failed\n");
206			return rc;
207		}
208	}
209
210	secs = value[0] | (value[1] << 8) | (value[2] << 16) |
211	       ((unsigned long)value[3] << 24);
212
213	rtc_time64_to_tm(secs, tm);
214
215	dev_dbg(dev, "secs = %lu, h:m:s == %ptRt, y-m-d = %ptRdr\n", secs, tm, tm);
216
217	return 0;
218}
219
220static int pm8xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
221{
222	int rc, i;
223	u8 value[NUM_8_BIT_RTC_REGS];
224	unsigned int ctrl_reg;
225	unsigned long secs, irq_flags;
226	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
227	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
228
229	secs = rtc_tm_to_time64(&alarm->time);
230
231	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
232		value[i] = secs & 0xFF;
233		secs >>= 8;
234	}
235
236	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
237
238	rc = regmap_bulk_write(rtc_dd->regmap, regs->alarm_rw, value,
239			       sizeof(value));
240	if (rc) {
241		dev_err(dev, "Write to RTC ALARM register failed\n");
242		goto rtc_rw_fail;
243	}
244
245	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
246	if (rc)
247		goto rtc_rw_fail;
248
249	if (alarm->enabled)
250		ctrl_reg |= regs->alarm_en;
251	else
252		ctrl_reg &= ~regs->alarm_en;
253
254	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
255	if (rc) {
256		dev_err(dev, "Write to RTC alarm control register failed\n");
257		goto rtc_rw_fail;
258	}
259
260	dev_dbg(dev, "Alarm Set for h:m:s=%ptRt, y-m-d=%ptRdr\n",
261		&alarm->time, &alarm->time);
262rtc_rw_fail:
263	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
264	return rc;
265}
266
267static int pm8xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
268{
269	int rc;
270	unsigned int ctrl_reg;
271	u8 value[NUM_8_BIT_RTC_REGS];
272	unsigned long secs;
273	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
274	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
275
276	rc = regmap_bulk_read(rtc_dd->regmap, regs->alarm_rw, value,
277			      sizeof(value));
278	if (rc) {
279		dev_err(dev, "RTC alarm time read failed\n");
280		return rc;
281	}
282
283	secs = value[0] | (value[1] << 8) | (value[2] << 16) |
284	       ((unsigned long)value[3] << 24);
285
286	rtc_time64_to_tm(secs, &alarm->time);
287
288	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
289	if (rc) {
290		dev_err(dev, "Read from RTC alarm control register failed\n");
291		return rc;
292	}
293	alarm->enabled = !!(ctrl_reg & PM8xxx_RTC_ALARM_ENABLE);
294
295	dev_dbg(dev, "Alarm set for - h:m:s=%ptRt, y-m-d=%ptRdr\n",
296		&alarm->time, &alarm->time);
297
298	return 0;
299}
300
301static int pm8xxx_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
302{
303	int rc;
304	unsigned long irq_flags;
305	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
306	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
307	unsigned int ctrl_reg;
308	u8 value[NUM_8_BIT_RTC_REGS] = {0};
309
310	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
311
312	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
313	if (rc)
314		goto rtc_rw_fail;
315
316	if (enable)
317		ctrl_reg |= regs->alarm_en;
318	else
319		ctrl_reg &= ~regs->alarm_en;
320
321	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
322	if (rc) {
323		dev_err(dev, "Write to RTC control register failed\n");
324		goto rtc_rw_fail;
325	}
326
327	/* Clear Alarm register */
328	if (!enable) {
329		rc = regmap_bulk_write(rtc_dd->regmap, regs->alarm_rw, value,
330				       sizeof(value));
331		if (rc) {
332			dev_err(dev, "Clear RTC ALARM register failed\n");
333			goto rtc_rw_fail;
334		}
335	}
336
337rtc_rw_fail:
338	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
339	return rc;
340}
341
342static const struct rtc_class_ops pm8xxx_rtc_ops = {
343	.read_time	= pm8xxx_rtc_read_time,
344	.set_time	= pm8xxx_rtc_set_time,
345	.set_alarm	= pm8xxx_rtc_set_alarm,
346	.read_alarm	= pm8xxx_rtc_read_alarm,
347	.alarm_irq_enable = pm8xxx_rtc_alarm_irq_enable,
348};
349
350static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
351{
352	struct pm8xxx_rtc *rtc_dd = dev_id;
353	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
354	unsigned int ctrl_reg;
355	int rc;
 
356
357	rtc_update_irq(rtc_dd->rtc, 1, RTC_IRQF | RTC_AF);
358
359	spin_lock(&rtc_dd->ctrl_reg_lock);
360
361	/* Clear the alarm enable bit */
362	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
363	if (rc) {
364		spin_unlock(&rtc_dd->ctrl_reg_lock);
365		goto rtc_alarm_handled;
366	}
367
368	ctrl_reg &= ~regs->alarm_en;
369
370	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
371	if (rc) {
372		spin_unlock(&rtc_dd->ctrl_reg_lock);
373		dev_err(rtc_dd->rtc_dev,
374			"Write to alarm control register failed\n");
375		goto rtc_alarm_handled;
376	}
377
378	spin_unlock(&rtc_dd->ctrl_reg_lock);
379
380	/* Clear RTC alarm register */
381	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl2, &ctrl_reg);
382	if (rc) {
383		dev_err(rtc_dd->rtc_dev,
384			"RTC Alarm control2 register read failed\n");
385		goto rtc_alarm_handled;
386	}
387
388	ctrl_reg |= PM8xxx_RTC_ALARM_CLEAR;
389	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl2, ctrl_reg);
390	if (rc)
391		dev_err(rtc_dd->rtc_dev,
392			"Write to RTC Alarm control2 register failed\n");
393
394rtc_alarm_handled:
395	return IRQ_HANDLED;
396}
397
398static int pm8xxx_rtc_enable(struct pm8xxx_rtc *rtc_dd)
399{
400	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
401	unsigned int ctrl_reg;
402	int rc;
403
404	/* Check if the RTC is on, else turn it on */
405	rc = regmap_read(rtc_dd->regmap, regs->ctrl, &ctrl_reg);
406	if (rc)
407		return rc;
408
409	if (!(ctrl_reg & PM8xxx_RTC_ENABLE)) {
410		ctrl_reg |= PM8xxx_RTC_ENABLE;
411		rc = regmap_write(rtc_dd->regmap, regs->ctrl, ctrl_reg);
412		if (rc)
413			return rc;
414	}
415
416	return 0;
417}
418
419static const struct pm8xxx_rtc_regs pm8921_regs = {
420	.ctrl		= 0x11d,
421	.write		= 0x11f,
422	.read		= 0x123,
423	.alarm_rw	= 0x127,
424	.alarm_ctrl	= 0x11d,
425	.alarm_ctrl2	= 0x11e,
426	.alarm_en	= BIT(1),
427};
428
429static const struct pm8xxx_rtc_regs pm8058_regs = {
430	.ctrl		= 0x1e8,
431	.write		= 0x1ea,
432	.read		= 0x1ee,
433	.alarm_rw	= 0x1f2,
434	.alarm_ctrl	= 0x1e8,
435	.alarm_ctrl2	= 0x1e9,
436	.alarm_en	= BIT(1),
437};
438
439static const struct pm8xxx_rtc_regs pm8941_regs = {
440	.ctrl		= 0x6046,
441	.write		= 0x6040,
442	.read		= 0x6048,
443	.alarm_rw	= 0x6140,
444	.alarm_ctrl	= 0x6146,
445	.alarm_ctrl2	= 0x6148,
446	.alarm_en	= BIT(7),
447};
448
449static const struct pm8xxx_rtc_regs pmk8350_regs = {
450	.ctrl		= 0x6146,
451	.write		= 0x6140,
452	.read		= 0x6148,
453	.alarm_rw	= 0x6240,
454	.alarm_ctrl	= 0x6246,
455	.alarm_ctrl2	= 0x6248,
456	.alarm_en	= BIT(7),
457};
458
459/*
460 * Hardcoded RTC bases until IORESOURCE_REG mapping is figured out
461 */
462static const struct of_device_id pm8xxx_id_table[] = {
463	{ .compatible = "qcom,pm8921-rtc", .data = &pm8921_regs },
 
464	{ .compatible = "qcom,pm8058-rtc", .data = &pm8058_regs },
465	{ .compatible = "qcom,pm8941-rtc", .data = &pm8941_regs },
466	{ .compatible = "qcom,pmk8350-rtc", .data = &pmk8350_regs },
467	{ },
468};
469MODULE_DEVICE_TABLE(of, pm8xxx_id_table);
470
471static int pm8xxx_rtc_probe(struct platform_device *pdev)
472{
473	int rc;
474	struct pm8xxx_rtc *rtc_dd;
475	const struct of_device_id *match;
476
477	match = of_match_node(pm8xxx_id_table, pdev->dev.of_node);
478	if (!match)
479		return -ENXIO;
480
481	rtc_dd = devm_kzalloc(&pdev->dev, sizeof(*rtc_dd), GFP_KERNEL);
482	if (rtc_dd == NULL)
483		return -ENOMEM;
484
485	/* Initialise spinlock to protect RTC control register */
486	spin_lock_init(&rtc_dd->ctrl_reg_lock);
487
488	rtc_dd->regmap = dev_get_regmap(pdev->dev.parent, NULL);
489	if (!rtc_dd->regmap) {
490		dev_err(&pdev->dev, "Parent regmap unavailable.\n");
491		return -ENXIO;
492	}
493
494	rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 0);
495	if (rtc_dd->rtc_alarm_irq < 0)
496		return -ENXIO;
497
498	rtc_dd->allow_set_time = of_property_read_bool(pdev->dev.of_node,
499						      "allow-set-time");
500
501	rtc_dd->regs = match->data;
502	rtc_dd->rtc_dev = &pdev->dev;
503
504	rc = pm8xxx_rtc_enable(rtc_dd);
505	if (rc)
506		return rc;
507
508	platform_set_drvdata(pdev, rtc_dd);
509
510	device_init_wakeup(&pdev->dev, 1);
511
512	/* Register the RTC device */
513	rtc_dd->rtc = devm_rtc_allocate_device(&pdev->dev);
514	if (IS_ERR(rtc_dd->rtc))
515		return PTR_ERR(rtc_dd->rtc);
516
517	rtc_dd->rtc->ops = &pm8xxx_rtc_ops;
518	rtc_dd->rtc->range_max = U32_MAX;
519
520	/* Request the alarm IRQ */
521	rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->rtc_alarm_irq,
522					  pm8xxx_alarm_trigger,
523					  IRQF_TRIGGER_RISING,
524					  "pm8xxx_rtc_alarm", rtc_dd);
525	if (rc < 0) {
526		dev_err(&pdev->dev, "Request IRQ failed (%d)\n", rc);
527		return rc;
528	}
529
530	rc = devm_rtc_register_device(rtc_dd->rtc);
531	if (rc)
532		return rc;
533
534	rc = dev_pm_set_wake_irq(&pdev->dev, rtc_dd->rtc_alarm_irq);
535	if (rc)
536		return rc;
 
 
 
 
537
538	return 0;
539}
540
541static int pm8xxx_remove(struct platform_device *pdev)
542{
543	dev_pm_clear_wake_irq(&pdev->dev);
 
 
 
 
544	return 0;
545}
 
 
 
 
 
546
547static struct platform_driver pm8xxx_rtc_driver = {
548	.probe		= pm8xxx_rtc_probe,
549	.remove		= pm8xxx_remove,
550	.driver	= {
551		.name		= "rtc-pm8xxx",
 
552		.of_match_table	= pm8xxx_id_table,
553	},
554};
555
556module_platform_driver(pm8xxx_rtc_driver);
557
558MODULE_ALIAS("platform:rtc-pm8xxx");
559MODULE_DESCRIPTION("PMIC8xxx RTC driver");
560MODULE_LICENSE("GPL v2");
561MODULE_AUTHOR("Anirudh Ghayal <aghayal@codeaurora.org>");
v5.9
  1// SPDX-License-Identifier: GPL-2.0-only
  2/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
  3 */
  4#include <linux/of.h>
  5#include <linux/module.h>
  6#include <linux/init.h>
  7#include <linux/rtc.h>
  8#include <linux/platform_device.h>
  9#include <linux/pm.h>
 
 10#include <linux/regmap.h>
 11#include <linux/slab.h>
 12#include <linux/spinlock.h>
 13
 14/* RTC Register offsets from RTC CTRL REG */
 15#define PM8XXX_ALARM_CTRL_OFFSET	0x01
 16#define PM8XXX_RTC_WRITE_OFFSET		0x02
 17#define PM8XXX_RTC_READ_OFFSET		0x06
 18#define PM8XXX_ALARM_RW_OFFSET		0x0A
 19
 20/* RTC_CTRL register bit fields */
 21#define PM8xxx_RTC_ENABLE		BIT(7)
 22#define PM8xxx_RTC_ALARM_CLEAR		BIT(0)
 
 23
 24#define NUM_8_BIT_RTC_REGS		0x4
 25
 26/**
 27 * struct pm8xxx_rtc_regs - describe RTC registers per PMIC versions
 28 * @ctrl: base address of control register
 29 * @write: base address of write register
 30 * @read: base address of read register
 31 * @alarm_ctrl: base address of alarm control register
 32 * @alarm_ctrl2: base address of alarm control2 register
 33 * @alarm_rw: base address of alarm read-write register
 34 * @alarm_en: alarm enable mask
 35 */
 36struct pm8xxx_rtc_regs {
 37	unsigned int ctrl;
 38	unsigned int write;
 39	unsigned int read;
 40	unsigned int alarm_ctrl;
 41	unsigned int alarm_ctrl2;
 42	unsigned int alarm_rw;
 43	unsigned int alarm_en;
 44};
 45
 46/**
 47 * struct pm8xxx_rtc -  rtc driver internal structure
 48 * @rtc:		rtc device for this driver.
 49 * @regmap:		regmap used to access RTC registers
 50 * @allow_set_time:	indicates whether writing to the RTC is allowed
 51 * @rtc_alarm_irq:	rtc alarm irq number.
 52 * @regs:		rtc registers description.
 53 * @rtc_dev:		device structure.
 54 * @ctrl_reg_lock:	spinlock protecting access to ctrl_reg.
 55 */
 56struct pm8xxx_rtc {
 57	struct rtc_device *rtc;
 58	struct regmap *regmap;
 59	bool allow_set_time;
 60	int rtc_alarm_irq;
 61	const struct pm8xxx_rtc_regs *regs;
 62	struct device *rtc_dev;
 63	spinlock_t ctrl_reg_lock;
 64};
 65
 66/*
 67 * Steps to write the RTC registers.
 68 * 1. Disable alarm if enabled.
 69 * 2. Disable rtc if enabled.
 70 * 3. Write 0x00 to LSB.
 71 * 4. Write Byte[1], Byte[2], Byte[3] then Byte[0].
 72 * 5. Enable rtc if disabled in step 2.
 73 * 6. Enable alarm if disabled in step 1.
 74 */
 75static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
 76{
 77	int rc, i;
 78	unsigned long secs, irq_flags;
 79	u8 value[NUM_8_BIT_RTC_REGS], alarm_enabled = 0, rtc_disabled = 0;
 80	unsigned int ctrl_reg, rtc_ctrl_reg;
 81	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
 82	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
 83
 84	if (!rtc_dd->allow_set_time)
 85		return -EACCES;
 86
 87	secs = rtc_tm_to_time64(tm);
 88
 89	dev_dbg(dev, "Seconds value to be written to RTC = %lu\n", secs);
 90
 91	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
 92		value[i] = secs & 0xFF;
 93		secs >>= 8;
 94	}
 95
 96	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
 97
 98	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
 99	if (rc)
100		goto rtc_rw_fail;
101
102	if (ctrl_reg & regs->alarm_en) {
103		alarm_enabled = 1;
104		ctrl_reg &= ~regs->alarm_en;
105		rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
106		if (rc) {
107			dev_err(dev, "Write to RTC Alarm control register failed\n");
108			goto rtc_rw_fail;
109		}
110	}
111
112	/* Disable RTC H/w before writing on RTC register */
113	rc = regmap_read(rtc_dd->regmap, regs->ctrl, &rtc_ctrl_reg);
114	if (rc)
115		goto rtc_rw_fail;
116
117	if (rtc_ctrl_reg & PM8xxx_RTC_ENABLE) {
118		rtc_disabled = 1;
119		rtc_ctrl_reg &= ~PM8xxx_RTC_ENABLE;
120		rc = regmap_write(rtc_dd->regmap, regs->ctrl, rtc_ctrl_reg);
121		if (rc) {
122			dev_err(dev, "Write to RTC control register failed\n");
123			goto rtc_rw_fail;
124		}
125	}
126
127	/* Write 0 to Byte[0] */
128	rc = regmap_write(rtc_dd->regmap, regs->write, 0);
129	if (rc) {
130		dev_err(dev, "Write to RTC write data register failed\n");
131		goto rtc_rw_fail;
132	}
133
134	/* Write Byte[1], Byte[2], Byte[3] */
135	rc = regmap_bulk_write(rtc_dd->regmap, regs->write + 1,
136			       &value[1], sizeof(value) - 1);
137	if (rc) {
138		dev_err(dev, "Write to RTC write data register failed\n");
139		goto rtc_rw_fail;
140	}
141
142	/* Write Byte[0] */
143	rc = regmap_write(rtc_dd->regmap, regs->write, value[0]);
144	if (rc) {
145		dev_err(dev, "Write to RTC write data register failed\n");
146		goto rtc_rw_fail;
147	}
148
149	/* Enable RTC H/w after writing on RTC register */
150	if (rtc_disabled) {
151		rtc_ctrl_reg |= PM8xxx_RTC_ENABLE;
152		rc = regmap_write(rtc_dd->regmap, regs->ctrl, rtc_ctrl_reg);
153		if (rc) {
154			dev_err(dev, "Write to RTC control register failed\n");
155			goto rtc_rw_fail;
156		}
157	}
158
159	if (alarm_enabled) {
160		ctrl_reg |= regs->alarm_en;
161		rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
162		if (rc) {
163			dev_err(dev, "Write to RTC Alarm control register failed\n");
164			goto rtc_rw_fail;
165		}
166	}
167
168rtc_rw_fail:
169	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
170
171	return rc;
172}
173
174static int pm8xxx_rtc_read_time(struct device *dev, struct rtc_time *tm)
175{
176	int rc;
177	u8 value[NUM_8_BIT_RTC_REGS];
178	unsigned long secs;
179	unsigned int reg;
180	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
181	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
182
183	rc = regmap_bulk_read(rtc_dd->regmap, regs->read, value, sizeof(value));
184	if (rc) {
185		dev_err(dev, "RTC read data register failed\n");
186		return rc;
187	}
188
189	/*
190	 * Read the LSB again and check if there has been a carry over.
191	 * If there is, redo the read operation.
192	 */
193	rc = regmap_read(rtc_dd->regmap, regs->read, &reg);
194	if (rc < 0) {
195		dev_err(dev, "RTC read data register failed\n");
196		return rc;
197	}
198
199	if (unlikely(reg < value[0])) {
200		rc = regmap_bulk_read(rtc_dd->regmap, regs->read,
201				      value, sizeof(value));
202		if (rc) {
203			dev_err(dev, "RTC read data register failed\n");
204			return rc;
205		}
206	}
207
208	secs = value[0] | (value[1] << 8) | (value[2] << 16) |
209	       ((unsigned long)value[3] << 24);
210
211	rtc_time64_to_tm(secs, tm);
212
213	dev_dbg(dev, "secs = %lu, h:m:s == %ptRt, y-m-d = %ptRdr\n", secs, tm, tm);
214
215	return 0;
216}
217
218static int pm8xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
219{
220	int rc, i;
221	u8 value[NUM_8_BIT_RTC_REGS];
222	unsigned int ctrl_reg;
223	unsigned long secs, irq_flags;
224	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
225	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
226
227	secs = rtc_tm_to_time64(&alarm->time);
228
229	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
230		value[i] = secs & 0xFF;
231		secs >>= 8;
232	}
233
234	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
235
236	rc = regmap_bulk_write(rtc_dd->regmap, regs->alarm_rw, value,
237			       sizeof(value));
238	if (rc) {
239		dev_err(dev, "Write to RTC ALARM register failed\n");
240		goto rtc_rw_fail;
241	}
242
243	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
244	if (rc)
245		goto rtc_rw_fail;
246
247	if (alarm->enabled)
248		ctrl_reg |= regs->alarm_en;
249	else
250		ctrl_reg &= ~regs->alarm_en;
251
252	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
253	if (rc) {
254		dev_err(dev, "Write to RTC alarm control register failed\n");
255		goto rtc_rw_fail;
256	}
257
258	dev_dbg(dev, "Alarm Set for h:m:s=%ptRt, y-m-d=%ptRdr\n",
259		&alarm->time, &alarm->time);
260rtc_rw_fail:
261	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
262	return rc;
263}
264
265static int pm8xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
266{
267	int rc;
 
268	u8 value[NUM_8_BIT_RTC_REGS];
269	unsigned long secs;
270	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
271	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
272
273	rc = regmap_bulk_read(rtc_dd->regmap, regs->alarm_rw, value,
274			      sizeof(value));
275	if (rc) {
276		dev_err(dev, "RTC alarm time read failed\n");
277		return rc;
278	}
279
280	secs = value[0] | (value[1] << 8) | (value[2] << 16) |
281	       ((unsigned long)value[3] << 24);
282
283	rtc_time64_to_tm(secs, &alarm->time);
284
 
 
 
 
 
 
 
285	dev_dbg(dev, "Alarm set for - h:m:s=%ptRt, y-m-d=%ptRdr\n",
286		&alarm->time, &alarm->time);
287
288	return 0;
289}
290
291static int pm8xxx_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
292{
293	int rc;
294	unsigned long irq_flags;
295	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
296	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
297	unsigned int ctrl_reg;
298	u8 value[NUM_8_BIT_RTC_REGS] = {0};
299
300	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
301
302	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
303	if (rc)
304		goto rtc_rw_fail;
305
306	if (enable)
307		ctrl_reg |= regs->alarm_en;
308	else
309		ctrl_reg &= ~regs->alarm_en;
310
311	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
312	if (rc) {
313		dev_err(dev, "Write to RTC control register failed\n");
314		goto rtc_rw_fail;
315	}
316
317	/* Clear Alarm register */
318	if (!enable) {
319		rc = regmap_bulk_write(rtc_dd->regmap, regs->alarm_rw, value,
320				       sizeof(value));
321		if (rc) {
322			dev_err(dev, "Clear RTC ALARM register failed\n");
323			goto rtc_rw_fail;
324		}
325	}
326
327rtc_rw_fail:
328	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
329	return rc;
330}
331
332static const struct rtc_class_ops pm8xxx_rtc_ops = {
333	.read_time	= pm8xxx_rtc_read_time,
334	.set_time	= pm8xxx_rtc_set_time,
335	.set_alarm	= pm8xxx_rtc_set_alarm,
336	.read_alarm	= pm8xxx_rtc_read_alarm,
337	.alarm_irq_enable = pm8xxx_rtc_alarm_irq_enable,
338};
339
340static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
341{
342	struct pm8xxx_rtc *rtc_dd = dev_id;
343	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
344	unsigned int ctrl_reg;
345	int rc;
346	unsigned long irq_flags;
347
348	rtc_update_irq(rtc_dd->rtc, 1, RTC_IRQF | RTC_AF);
349
350	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
351
352	/* Clear the alarm enable bit */
353	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
354	if (rc) {
355		spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
356		goto rtc_alarm_handled;
357	}
358
359	ctrl_reg &= ~regs->alarm_en;
360
361	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
362	if (rc) {
363		spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
364		dev_err(rtc_dd->rtc_dev,
365			"Write to alarm control register failed\n");
366		goto rtc_alarm_handled;
367	}
368
369	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
370
371	/* Clear RTC alarm register */
372	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl2, &ctrl_reg);
373	if (rc) {
374		dev_err(rtc_dd->rtc_dev,
375			"RTC Alarm control2 register read failed\n");
376		goto rtc_alarm_handled;
377	}
378
379	ctrl_reg |= PM8xxx_RTC_ALARM_CLEAR;
380	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl2, ctrl_reg);
381	if (rc)
382		dev_err(rtc_dd->rtc_dev,
383			"Write to RTC Alarm control2 register failed\n");
384
385rtc_alarm_handled:
386	return IRQ_HANDLED;
387}
388
389static int pm8xxx_rtc_enable(struct pm8xxx_rtc *rtc_dd)
390{
391	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
392	unsigned int ctrl_reg;
393	int rc;
394
395	/* Check if the RTC is on, else turn it on */
396	rc = regmap_read(rtc_dd->regmap, regs->ctrl, &ctrl_reg);
397	if (rc)
398		return rc;
399
400	if (!(ctrl_reg & PM8xxx_RTC_ENABLE)) {
401		ctrl_reg |= PM8xxx_RTC_ENABLE;
402		rc = regmap_write(rtc_dd->regmap, regs->ctrl, ctrl_reg);
403		if (rc)
404			return rc;
405	}
406
407	return 0;
408}
409
410static const struct pm8xxx_rtc_regs pm8921_regs = {
411	.ctrl		= 0x11d,
412	.write		= 0x11f,
413	.read		= 0x123,
414	.alarm_rw	= 0x127,
415	.alarm_ctrl	= 0x11d,
416	.alarm_ctrl2	= 0x11e,
417	.alarm_en	= BIT(1),
418};
419
420static const struct pm8xxx_rtc_regs pm8058_regs = {
421	.ctrl		= 0x1e8,
422	.write		= 0x1ea,
423	.read		= 0x1ee,
424	.alarm_rw	= 0x1f2,
425	.alarm_ctrl	= 0x1e8,
426	.alarm_ctrl2	= 0x1e9,
427	.alarm_en	= BIT(1),
428};
429
430static const struct pm8xxx_rtc_regs pm8941_regs = {
431	.ctrl		= 0x6046,
432	.write		= 0x6040,
433	.read		= 0x6048,
434	.alarm_rw	= 0x6140,
435	.alarm_ctrl	= 0x6146,
436	.alarm_ctrl2	= 0x6148,
437	.alarm_en	= BIT(7),
438};
439
 
 
 
 
 
 
 
 
 
 
440/*
441 * Hardcoded RTC bases until IORESOURCE_REG mapping is figured out
442 */
443static const struct of_device_id pm8xxx_id_table[] = {
444	{ .compatible = "qcom,pm8921-rtc", .data = &pm8921_regs },
445	{ .compatible = "qcom,pm8018-rtc", .data = &pm8921_regs },
446	{ .compatible = "qcom,pm8058-rtc", .data = &pm8058_regs },
447	{ .compatible = "qcom,pm8941-rtc", .data = &pm8941_regs },
 
448	{ },
449};
450MODULE_DEVICE_TABLE(of, pm8xxx_id_table);
451
452static int pm8xxx_rtc_probe(struct platform_device *pdev)
453{
454	int rc;
455	struct pm8xxx_rtc *rtc_dd;
456	const struct of_device_id *match;
457
458	match = of_match_node(pm8xxx_id_table, pdev->dev.of_node);
459	if (!match)
460		return -ENXIO;
461
462	rtc_dd = devm_kzalloc(&pdev->dev, sizeof(*rtc_dd), GFP_KERNEL);
463	if (rtc_dd == NULL)
464		return -ENOMEM;
465
466	/* Initialise spinlock to protect RTC control register */
467	spin_lock_init(&rtc_dd->ctrl_reg_lock);
468
469	rtc_dd->regmap = dev_get_regmap(pdev->dev.parent, NULL);
470	if (!rtc_dd->regmap) {
471		dev_err(&pdev->dev, "Parent regmap unavailable.\n");
472		return -ENXIO;
473	}
474
475	rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 0);
476	if (rtc_dd->rtc_alarm_irq < 0)
477		return -ENXIO;
478
479	rtc_dd->allow_set_time = of_property_read_bool(pdev->dev.of_node,
480						      "allow-set-time");
481
482	rtc_dd->regs = match->data;
483	rtc_dd->rtc_dev = &pdev->dev;
484
485	rc = pm8xxx_rtc_enable(rtc_dd);
486	if (rc)
487		return rc;
488
489	platform_set_drvdata(pdev, rtc_dd);
490
491	device_init_wakeup(&pdev->dev, 1);
492
493	/* Register the RTC device */
494	rtc_dd->rtc = devm_rtc_allocate_device(&pdev->dev);
495	if (IS_ERR(rtc_dd->rtc))
496		return PTR_ERR(rtc_dd->rtc);
497
498	rtc_dd->rtc->ops = &pm8xxx_rtc_ops;
499	rtc_dd->rtc->range_max = U32_MAX;
500
501	/* Request the alarm IRQ */
502	rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->rtc_alarm_irq,
503					  pm8xxx_alarm_trigger,
504					  IRQF_TRIGGER_RISING,
505					  "pm8xxx_rtc_alarm", rtc_dd);
506	if (rc < 0) {
507		dev_err(&pdev->dev, "Request IRQ failed (%d)\n", rc);
508		return rc;
509	}
510
511	return rtc_register_device(rtc_dd->rtc);
512}
 
513
514#ifdef CONFIG_PM_SLEEP
515static int pm8xxx_rtc_resume(struct device *dev)
516{
517	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
518
519	if (device_may_wakeup(dev))
520		disable_irq_wake(rtc_dd->rtc_alarm_irq);
521
522	return 0;
523}
524
525static int pm8xxx_rtc_suspend(struct device *dev)
526{
527	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
528
529	if (device_may_wakeup(dev))
530		enable_irq_wake(rtc_dd->rtc_alarm_irq);
531
532	return 0;
533}
534#endif
535
536static SIMPLE_DEV_PM_OPS(pm8xxx_rtc_pm_ops,
537			 pm8xxx_rtc_suspend,
538			 pm8xxx_rtc_resume);
539
540static struct platform_driver pm8xxx_rtc_driver = {
541	.probe		= pm8xxx_rtc_probe,
 
542	.driver	= {
543		.name		= "rtc-pm8xxx",
544		.pm		= &pm8xxx_rtc_pm_ops,
545		.of_match_table	= pm8xxx_id_table,
546	},
547};
548
549module_platform_driver(pm8xxx_rtc_driver);
550
551MODULE_ALIAS("platform:rtc-pm8xxx");
552MODULE_DESCRIPTION("PMIC8xxx RTC driver");
553MODULE_LICENSE("GPL v2");
554MODULE_AUTHOR("Anirudh Ghayal <aghayal@codeaurora.org>");