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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>");
v4.10.11
 
  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,pm8018-rtc", .data = &pm8921_regs },
432	{ .compatible = "qcom,pm8058-rtc", .data = &pm8058_regs },
433	{ .compatible = "qcom,pm8941-rtc", .data = &pm8941_regs },
434	{ },
435};
436MODULE_DEVICE_TABLE(of, pm8xxx_id_table);
437
438static int pm8xxx_rtc_probe(struct platform_device *pdev)
439{
440	int rc;
441	struct pm8xxx_rtc *rtc_dd;
442	const struct of_device_id *match;
443
444	match = of_match_node(pm8xxx_id_table, pdev->dev.of_node);
445	if (!match)
446		return -ENXIO;
447
448	rtc_dd = devm_kzalloc(&pdev->dev, sizeof(*rtc_dd), GFP_KERNEL);
449	if (rtc_dd == NULL)
450		return -ENOMEM;
451
452	/* Initialise spinlock to protect RTC control register */
453	spin_lock_init(&rtc_dd->ctrl_reg_lock);
454
455	rtc_dd->regmap = dev_get_regmap(pdev->dev.parent, NULL);
456	if (!rtc_dd->regmap) {
457		dev_err(&pdev->dev, "Parent regmap unavailable.\n");
458		return -ENXIO;
459	}
460
461	rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 0);
462	if (rtc_dd->rtc_alarm_irq < 0) {
463		dev_err(&pdev->dev, "Alarm IRQ resource absent!\n");
464		return -ENXIO;
465	}
466
467	rtc_dd->allow_set_time = of_property_read_bool(pdev->dev.of_node,
468						      "allow-set-time");
469
470	rtc_dd->regs = match->data;
471	rtc_dd->rtc_dev = &pdev->dev;
472
473	rc = pm8xxx_rtc_enable(rtc_dd);
474	if (rc)
475		return rc;
476
477	platform_set_drvdata(pdev, rtc_dd);
478
479	device_init_wakeup(&pdev->dev, 1);
480
481	/* Register the RTC device */
482	rtc_dd->rtc = devm_rtc_device_register(&pdev->dev, "pm8xxx_rtc",
483					       &pm8xxx_rtc_ops, THIS_MODULE);
484	if (IS_ERR(rtc_dd->rtc)) {
485		dev_err(&pdev->dev, "%s: RTC registration failed (%ld)\n",
486			__func__, PTR_ERR(rtc_dd->rtc));
487		return PTR_ERR(rtc_dd->rtc);
488	}
 
 
489
490	/* Request the alarm IRQ */
491	rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->rtc_alarm_irq,
492					  pm8xxx_alarm_trigger,
493					  IRQF_TRIGGER_RISING,
494					  "pm8xxx_rtc_alarm", rtc_dd);
495	if (rc < 0) {
496		dev_err(&pdev->dev, "Request IRQ failed (%d)\n", rc);
497		return rc;
498	}
499
500	dev_dbg(&pdev->dev, "Probe success !!\n");
501
502	return 0;
503}
504
505#ifdef CONFIG_PM_SLEEP
506static int pm8xxx_rtc_resume(struct device *dev)
507{
508	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
509
510	if (device_may_wakeup(dev))
511		disable_irq_wake(rtc_dd->rtc_alarm_irq);
512
513	return 0;
514}
515
516static int pm8xxx_rtc_suspend(struct device *dev)
517{
518	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
519
520	if (device_may_wakeup(dev))
521		enable_irq_wake(rtc_dd->rtc_alarm_irq);
522
523	return 0;
524}
525#endif
526
527static SIMPLE_DEV_PM_OPS(pm8xxx_rtc_pm_ops,
528			 pm8xxx_rtc_suspend,
529			 pm8xxx_rtc_resume);
530
531static struct platform_driver pm8xxx_rtc_driver = {
532	.probe		= pm8xxx_rtc_probe,
533	.driver	= {
534		.name		= "rtc-pm8xxx",
535		.pm		= &pm8xxx_rtc_pm_ops,
536		.of_match_table	= pm8xxx_id_table,
537	},
538};
539
540module_platform_driver(pm8xxx_rtc_driver);
541
542MODULE_ALIAS("platform:rtc-pm8xxx");
543MODULE_DESCRIPTION("PMIC8xxx RTC driver");
544MODULE_LICENSE("GPL v2");
545MODULE_AUTHOR("Anirudh Ghayal <aghayal@codeaurora.org>");