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v4.6
 
  1/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
  2 *
  3 * This program is free software; you can redistribute it and/or modify
  4 * it under the terms of the GNU General Public License version 2 and
  5 * only version 2 as published by the Free Software Foundation.
  6 *
  7 * This program is distributed in the hope that it will be useful,
  8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 10 * GNU General Public License for more details.
 11 */
 12#include <linux/of.h>
 13#include <linux/module.h>
 14#include <linux/init.h>
 15#include <linux/rtc.h>
 16#include <linux/platform_device.h>
 17#include <linux/pm.h>
 
 18#include <linux/regmap.h>
 19#include <linux/slab.h>
 20#include <linux/spinlock.h>
 21
 22/* RTC Register offsets from RTC CTRL REG */
 23#define PM8XXX_ALARM_CTRL_OFFSET	0x01
 24#define PM8XXX_RTC_WRITE_OFFSET		0x02
 25#define PM8XXX_RTC_READ_OFFSET		0x06
 26#define PM8XXX_ALARM_RW_OFFSET		0x0A
 27
 28/* RTC_CTRL register bit fields */
 29#define PM8xxx_RTC_ENABLE		BIT(7)
 30#define PM8xxx_RTC_ALARM_CLEAR		BIT(0)
 
 31
 32#define NUM_8_BIT_RTC_REGS		0x4
 33
 34/**
 35 * struct pm8xxx_rtc_regs - describe RTC registers per PMIC versions
 36 * @ctrl: base address of control register
 37 * @write: base address of write register
 38 * @read: base address of read register
 39 * @alarm_ctrl: base address of alarm control register
 40 * @alarm_ctrl2: base address of alarm control2 register
 41 * @alarm_rw: base address of alarm read-write register
 42 * @alarm_en: alarm enable mask
 43 */
 44struct pm8xxx_rtc_regs {
 45	unsigned int ctrl;
 46	unsigned int write;
 47	unsigned int read;
 48	unsigned int alarm_ctrl;
 49	unsigned int alarm_ctrl2;
 50	unsigned int alarm_rw;
 51	unsigned int alarm_en;
 52};
 53
 54/**
 55 * struct pm8xxx_rtc -  rtc driver internal structure
 56 * @rtc:		rtc device for this driver.
 57 * @regmap:		regmap used to access RTC registers
 58 * @allow_set_time:	indicates whether writing to the RTC is allowed
 59 * @rtc_alarm_irq:	rtc alarm irq number.
 60 * @ctrl_reg:		rtc control register.
 61 * @rtc_dev:		device structure.
 62 * @ctrl_reg_lock:	spinlock protecting access to ctrl_reg.
 63 */
 64struct pm8xxx_rtc {
 65	struct rtc_device *rtc;
 66	struct regmap *regmap;
 67	bool allow_set_time;
 68	int rtc_alarm_irq;
 69	const struct pm8xxx_rtc_regs *regs;
 70	struct device *rtc_dev;
 71	spinlock_t ctrl_reg_lock;
 72};
 73
 74/*
 75 * Steps to write the RTC registers.
 76 * 1. Disable alarm if enabled.
 77 * 2. Write 0x00 to LSB.
 78 * 3. Write Byte[1], Byte[2], Byte[3] then Byte[0].
 79 * 4. Enable alarm if disabled in step 1.
 
 
 80 */
 81static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
 82{
 83	int rc, i;
 84	unsigned long secs, irq_flags;
 85	u8 value[NUM_8_BIT_RTC_REGS], alarm_enabled = 0;
 86	unsigned int ctrl_reg;
 87	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
 88	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
 89
 90	if (!rtc_dd->allow_set_time)
 91		return -EACCES;
 
 
 92
 93	rtc_tm_to_time(tm, &secs);
 94
 95	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
 96		value[i] = secs & 0xFF;
 97		secs >>= 8;
 98	}
 99
100	dev_dbg(dev, "Seconds value to be written to RTC = %lu\n", secs);
101
102	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
103
104	rc = regmap_read(rtc_dd->regmap, regs->ctrl, &ctrl_reg);
105	if (rc)
106		goto rtc_rw_fail;
107
108	if (ctrl_reg & regs->alarm_en) {
109		alarm_enabled = 1;
110		ctrl_reg &= ~regs->alarm_en;
111		rc = regmap_write(rtc_dd->regmap, regs->ctrl, ctrl_reg);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
112		if (rc) {
113			dev_err(dev, "Write to RTC control register failed\n");
114			goto rtc_rw_fail;
115		}
116	}
117
118	/* Write 0 to Byte[0] */
119	rc = regmap_write(rtc_dd->regmap, regs->write, 0);
120	if (rc) {
121		dev_err(dev, "Write to RTC write data register failed\n");
122		goto rtc_rw_fail;
123	}
124
125	/* Write Byte[1], Byte[2], Byte[3] */
126	rc = regmap_bulk_write(rtc_dd->regmap, regs->write + 1,
127			       &value[1], sizeof(value) - 1);
128	if (rc) {
129		dev_err(dev, "Write to RTC write data register failed\n");
130		goto rtc_rw_fail;
131	}
132
133	/* Write Byte[0] */
134	rc = regmap_write(rtc_dd->regmap, regs->write, value[0]);
135	if (rc) {
136		dev_err(dev, "Write to RTC write data register failed\n");
137		goto rtc_rw_fail;
138	}
139
 
 
 
 
 
 
 
 
 
 
140	if (alarm_enabled) {
141		ctrl_reg |= regs->alarm_en;
142		rc = regmap_write(rtc_dd->regmap, regs->ctrl, ctrl_reg);
143		if (rc) {
144			dev_err(dev, "Write to RTC control register failed\n");
145			goto rtc_rw_fail;
146		}
147	}
148
149rtc_rw_fail:
150	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
151
152	return rc;
153}
154
155static int pm8xxx_rtc_read_time(struct device *dev, struct rtc_time *tm)
156{
157	int rc;
158	u8 value[NUM_8_BIT_RTC_REGS];
159	unsigned long secs;
160	unsigned int reg;
161	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
162	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
163
164	rc = regmap_bulk_read(rtc_dd->regmap, regs->read, value, sizeof(value));
165	if (rc) {
166		dev_err(dev, "RTC read data register failed\n");
167		return rc;
168	}
169
170	/*
171	 * Read the LSB again and check if there has been a carry over.
172	 * If there is, redo the read operation.
173	 */
174	rc = regmap_read(rtc_dd->regmap, regs->read, &reg);
175	if (rc < 0) {
176		dev_err(dev, "RTC read data register failed\n");
177		return rc;
178	}
179
180	if (unlikely(reg < value[0])) {
181		rc = regmap_bulk_read(rtc_dd->regmap, regs->read,
182				      value, sizeof(value));
183		if (rc) {
184			dev_err(dev, "RTC read data register failed\n");
185			return rc;
186		}
187	}
188
189	secs = value[0] | (value[1] << 8) | (value[2] << 16) | (value[3] << 24);
 
190
191	rtc_time_to_tm(secs, tm);
192
193	rc = rtc_valid_tm(tm);
194	if (rc < 0) {
195		dev_err(dev, "Invalid time read from RTC\n");
196		return rc;
197	}
198
199	dev_dbg(dev, "secs = %lu, h:m:s == %d:%d:%d, d/m/y = %d/%d/%d\n",
200		secs, tm->tm_hour, tm->tm_min, tm->tm_sec,
201		tm->tm_mday, tm->tm_mon, tm->tm_year);
202
203	return 0;
204}
205
206static int pm8xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
207{
208	int rc, i;
209	u8 value[NUM_8_BIT_RTC_REGS];
210	unsigned int ctrl_reg;
211	unsigned long secs, irq_flags;
212	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
213	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
214
215	rtc_tm_to_time(&alarm->time, &secs);
216
217	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
218		value[i] = secs & 0xFF;
219		secs >>= 8;
220	}
221
222	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
223
224	rc = regmap_bulk_write(rtc_dd->regmap, regs->alarm_rw, value,
225			       sizeof(value));
226	if (rc) {
227		dev_err(dev, "Write to RTC ALARM register failed\n");
228		goto rtc_rw_fail;
229	}
230
231	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
232	if (rc)
233		goto rtc_rw_fail;
234
235	if (alarm->enabled)
236		ctrl_reg |= regs->alarm_en;
237	else
238		ctrl_reg &= ~regs->alarm_en;
239
240	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
241	if (rc) {
242		dev_err(dev, "Write to RTC alarm control register failed\n");
243		goto rtc_rw_fail;
244	}
245
246	dev_dbg(dev, "Alarm Set for h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",
247		alarm->time.tm_hour, alarm->time.tm_min,
248		alarm->time.tm_sec, alarm->time.tm_mday,
249		alarm->time.tm_mon, alarm->time.tm_year);
250rtc_rw_fail:
251	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
252	return rc;
253}
254
255static int pm8xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
256{
257	int rc;
 
258	u8 value[NUM_8_BIT_RTC_REGS];
259	unsigned long secs;
260	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
261	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
262
263	rc = regmap_bulk_read(rtc_dd->regmap, regs->alarm_rw, value,
264			      sizeof(value));
265	if (rc) {
266		dev_err(dev, "RTC alarm time read failed\n");
267		return rc;
268	}
269
270	secs = value[0] | (value[1] << 8) | (value[2] << 16) | (value[3] << 24);
 
271
272	rtc_time_to_tm(secs, &alarm->time);
273
274	rc = rtc_valid_tm(&alarm->time);
275	if (rc < 0) {
276		dev_err(dev, "Invalid alarm time read from RTC\n");
277		return rc;
278	}
 
279
280	dev_dbg(dev, "Alarm set for - h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",
281		alarm->time.tm_hour, alarm->time.tm_min,
282		alarm->time.tm_sec, alarm->time.tm_mday,
283		alarm->time.tm_mon, alarm->time.tm_year);
284
285	return 0;
286}
287
288static int pm8xxx_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
289{
290	int rc;
291	unsigned long irq_flags;
292	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
293	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
294	unsigned int ctrl_reg;
 
295
296	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
297
298	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
299	if (rc)
300		goto rtc_rw_fail;
301
302	if (enable)
303		ctrl_reg |= regs->alarm_en;
304	else
305		ctrl_reg &= ~regs->alarm_en;
306
307	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
308	if (rc) {
309		dev_err(dev, "Write to RTC control register failed\n");
310		goto rtc_rw_fail;
311	}
312
 
 
 
 
 
 
 
 
 
 
313rtc_rw_fail:
314	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
315	return rc;
316}
317
318static const struct rtc_class_ops pm8xxx_rtc_ops = {
319	.read_time	= pm8xxx_rtc_read_time,
320	.set_time	= pm8xxx_rtc_set_time,
321	.set_alarm	= pm8xxx_rtc_set_alarm,
322	.read_alarm	= pm8xxx_rtc_read_alarm,
323	.alarm_irq_enable = pm8xxx_rtc_alarm_irq_enable,
324};
325
326static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
327{
328	struct pm8xxx_rtc *rtc_dd = dev_id;
329	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
330	unsigned int ctrl_reg;
331	int rc;
332	unsigned long irq_flags;
333
334	rtc_update_irq(rtc_dd->rtc, 1, RTC_IRQF | RTC_AF);
335
336	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
337
338	/* Clear the alarm enable bit */
339	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
340	if (rc) {
341		spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
342		goto rtc_alarm_handled;
343	}
344
345	ctrl_reg &= ~regs->alarm_en;
346
347	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
348	if (rc) {
349		spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
350		dev_err(rtc_dd->rtc_dev,
351			"Write to alarm control register failed\n");
352		goto rtc_alarm_handled;
353	}
354
355	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
356
357	/* Clear RTC alarm register */
358	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl2, &ctrl_reg);
359	if (rc) {
360		dev_err(rtc_dd->rtc_dev,
361			"RTC Alarm control2 register read failed\n");
362		goto rtc_alarm_handled;
363	}
364
365	ctrl_reg |= PM8xxx_RTC_ALARM_CLEAR;
366	rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl2, ctrl_reg);
367	if (rc)
368		dev_err(rtc_dd->rtc_dev,
369			"Write to RTC Alarm control2 register failed\n");
370
371rtc_alarm_handled:
372	return IRQ_HANDLED;
373}
374
375static int pm8xxx_rtc_enable(struct pm8xxx_rtc *rtc_dd)
376{
377	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
378	unsigned int ctrl_reg;
379	int rc;
380
381	/* Check if the RTC is on, else turn it on */
382	rc = regmap_read(rtc_dd->regmap, regs->ctrl, &ctrl_reg);
383	if (rc)
384		return rc;
385
386	if (!(ctrl_reg & PM8xxx_RTC_ENABLE)) {
387		ctrl_reg |= PM8xxx_RTC_ENABLE;
388		rc = regmap_write(rtc_dd->regmap, regs->ctrl, ctrl_reg);
389		if (rc)
390			return rc;
391	}
392
393	return 0;
394}
395
396static const struct pm8xxx_rtc_regs pm8921_regs = {
397	.ctrl		= 0x11d,
398	.write		= 0x11f,
399	.read		= 0x123,
400	.alarm_rw	= 0x127,
401	.alarm_ctrl	= 0x11d,
402	.alarm_ctrl2	= 0x11e,
403	.alarm_en	= BIT(1),
404};
405
406static const struct pm8xxx_rtc_regs pm8058_regs = {
407	.ctrl		= 0x1e8,
408	.write		= 0x1ea,
409	.read		= 0x1ee,
410	.alarm_rw	= 0x1f2,
411	.alarm_ctrl	= 0x1e8,
412	.alarm_ctrl2	= 0x1e9,
413	.alarm_en	= BIT(1),
414};
415
416static const struct pm8xxx_rtc_regs pm8941_regs = {
417	.ctrl		= 0x6046,
418	.write		= 0x6040,
419	.read		= 0x6048,
420	.alarm_rw	= 0x6140,
421	.alarm_ctrl	= 0x6146,
422	.alarm_ctrl2	= 0x6148,
423	.alarm_en	= BIT(7),
424};
425
 
 
 
 
 
 
 
 
 
 
426/*
427 * Hardcoded RTC bases until IORESOURCE_REG mapping is figured out
428 */
429static const struct of_device_id pm8xxx_id_table[] = {
430	{ .compatible = "qcom,pm8921-rtc", .data = &pm8921_regs },
431	{ .compatible = "qcom,pm8058-rtc", .data = &pm8058_regs },
432	{ .compatible = "qcom,pm8941-rtc", .data = &pm8941_regs },
 
433	{ },
434};
435MODULE_DEVICE_TABLE(of, pm8xxx_id_table);
436
437static int pm8xxx_rtc_probe(struct platform_device *pdev)
438{
439	int rc;
440	struct pm8xxx_rtc *rtc_dd;
441	const struct of_device_id *match;
442
443	match = of_match_node(pm8xxx_id_table, pdev->dev.of_node);
444	if (!match)
445		return -ENXIO;
446
447	rtc_dd = devm_kzalloc(&pdev->dev, sizeof(*rtc_dd), GFP_KERNEL);
448	if (rtc_dd == NULL)
449		return -ENOMEM;
450
451	/* Initialise spinlock to protect RTC control register */
452	spin_lock_init(&rtc_dd->ctrl_reg_lock);
453
454	rtc_dd->regmap = dev_get_regmap(pdev->dev.parent, NULL);
455	if (!rtc_dd->regmap) {
456		dev_err(&pdev->dev, "Parent regmap unavailable.\n");
457		return -ENXIO;
458	}
459
460	rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 0);
461	if (rtc_dd->rtc_alarm_irq < 0) {
462		dev_err(&pdev->dev, "Alarm IRQ resource absent!\n");
463		return -ENXIO;
464	}
465
466	rtc_dd->allow_set_time = of_property_read_bool(pdev->dev.of_node,
467						      "allow-set-time");
468
469	rtc_dd->regs = match->data;
470	rtc_dd->rtc_dev = &pdev->dev;
471
472	rc = pm8xxx_rtc_enable(rtc_dd);
473	if (rc)
474		return rc;
475
476	platform_set_drvdata(pdev, rtc_dd);
477
478	device_init_wakeup(&pdev->dev, 1);
479
480	/* Register the RTC device */
481	rtc_dd->rtc = devm_rtc_device_register(&pdev->dev, "pm8xxx_rtc",
482					       &pm8xxx_rtc_ops, THIS_MODULE);
483	if (IS_ERR(rtc_dd->rtc)) {
484		dev_err(&pdev->dev, "%s: RTC registration failed (%ld)\n",
485			__func__, PTR_ERR(rtc_dd->rtc));
486		return PTR_ERR(rtc_dd->rtc);
487	}
 
 
488
489	/* Request the alarm IRQ */
490	rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->rtc_alarm_irq,
491					  pm8xxx_alarm_trigger,
492					  IRQF_TRIGGER_RISING,
493					  "pm8xxx_rtc_alarm", rtc_dd);
494	if (rc < 0) {
495		dev_err(&pdev->dev, "Request IRQ failed (%d)\n", rc);
496		return rc;
497	}
498
499	dev_dbg(&pdev->dev, "Probe success !!\n");
500
501	return 0;
502}
503
504#ifdef CONFIG_PM_SLEEP
505static int pm8xxx_rtc_resume(struct device *dev)
506{
507	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
508
509	if (device_may_wakeup(dev))
510		disable_irq_wake(rtc_dd->rtc_alarm_irq);
 
511
512	return 0;
513}
514
515static int pm8xxx_rtc_suspend(struct device *dev)
516{
517	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
518
519	if (device_may_wakeup(dev))
520		enable_irq_wake(rtc_dd->rtc_alarm_irq);
521
522	return 0;
523}
524#endif
525
526static SIMPLE_DEV_PM_OPS(pm8xxx_rtc_pm_ops,
527			 pm8xxx_rtc_suspend,
528			 pm8xxx_rtc_resume);
529
530static struct platform_driver pm8xxx_rtc_driver = {
531	.probe		= pm8xxx_rtc_probe,
 
532	.driver	= {
533		.name		= "rtc-pm8xxx",
534		.pm		= &pm8xxx_rtc_pm_ops,
535		.of_match_table	= pm8xxx_id_table,
536	},
537};
538
539module_platform_driver(pm8xxx_rtc_driver);
540
541MODULE_ALIAS("platform:rtc-pm8xxx");
542MODULE_DESCRIPTION("PMIC8xxx RTC driver");
543MODULE_LICENSE("GPL v2");
544MODULE_AUTHOR("Anirudh Ghayal <aghayal@codeaurora.org>");
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>");