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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>");
v3.15
  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_ENABLE		BIT(1)
 31#define PM8xxx_RTC_ALARM_CLEAR		BIT(0)
 32
 33#define NUM_8_BIT_RTC_REGS		0x4
 34
 35/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 36 * struct pm8xxx_rtc -  rtc driver internal structure
 37 * @rtc:		rtc device for this driver.
 38 * @regmap:		regmap used to access RTC registers
 39 * @allow_set_time:	indicates whether writing to the RTC is allowed
 40 * @rtc_alarm_irq:	rtc alarm irq number.
 41 * @rtc_base:		address of rtc control register.
 42 * @rtc_read_base:	base address of read registers.
 43 * @rtc_write_base:	base address of write registers.
 44 * @alarm_rw_base:	base address of alarm registers.
 45 * @ctrl_reg:		rtc control register.
 46 * @rtc_dev:		device structure.
 47 * @ctrl_reg_lock:	spinlock protecting access to ctrl_reg.
 48 */
 49struct pm8xxx_rtc {
 50	struct rtc_device *rtc;
 51	struct regmap *regmap;
 52	bool allow_set_time;
 53	int rtc_alarm_irq;
 54	int rtc_base;
 55	int rtc_read_base;
 56	int rtc_write_base;
 57	int alarm_rw_base;
 58	u8 ctrl_reg;
 59	struct device *rtc_dev;
 60	spinlock_t ctrl_reg_lock;
 61};
 62
 63/*
 64 * Steps to write the RTC registers.
 65 * 1. Disable alarm if enabled.
 66 * 2. Write 0x00 to LSB.
 67 * 3. Write Byte[1], Byte[2], Byte[3] then Byte[0].
 68 * 4. Enable alarm if disabled in step 1.
 69 */
 70static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
 71{
 72	int rc, i;
 73	unsigned long secs, irq_flags;
 74	u8 value[NUM_8_BIT_RTC_REGS], alarm_enabled = 0, ctrl_reg;
 
 75	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
 
 76
 77	if (!rtc_dd->allow_set_time)
 78		return -EACCES;
 79
 80	rtc_tm_to_time(tm, &secs);
 81
 82	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
 83		value[i] = secs & 0xFF;
 84		secs >>= 8;
 85	}
 86
 87	dev_dbg(dev, "Seconds value to be written to RTC = %lu\n", secs);
 88
 89	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
 90	ctrl_reg = rtc_dd->ctrl_reg;
 91
 92	if (ctrl_reg & PM8xxx_RTC_ALARM_ENABLE) {
 
 
 
 
 93		alarm_enabled = 1;
 94		ctrl_reg &= ~PM8xxx_RTC_ALARM_ENABLE;
 95		rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
 96		if (rc) {
 97			dev_err(dev, "Write to RTC control register failed\n");
 98			goto rtc_rw_fail;
 99		}
100		rtc_dd->ctrl_reg = ctrl_reg;
101	} else {
102		spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
103	}
104
105	/* Write 0 to Byte[0] */
106	rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_write_base, 0);
107	if (rc) {
108		dev_err(dev, "Write to RTC write data register failed\n");
109		goto rtc_rw_fail;
110	}
111
112	/* Write Byte[1], Byte[2], Byte[3] */
113	rc = regmap_bulk_write(rtc_dd->regmap, rtc_dd->rtc_write_base + 1,
114			       &value[1], sizeof(value) - 1);
115	if (rc) {
116		dev_err(dev, "Write to RTC write data register failed\n");
117		goto rtc_rw_fail;
118	}
119
120	/* Write Byte[0] */
121	rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_write_base, value[0]);
122	if (rc) {
123		dev_err(dev, "Write to RTC write data register failed\n");
124		goto rtc_rw_fail;
125	}
126
127	if (alarm_enabled) {
128		ctrl_reg |= PM8xxx_RTC_ALARM_ENABLE;
129		rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
130		if (rc) {
131			dev_err(dev, "Write to RTC control register failed\n");
132			goto rtc_rw_fail;
133		}
134		rtc_dd->ctrl_reg = ctrl_reg;
135	}
136
137rtc_rw_fail:
138	if (alarm_enabled)
139		spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
140
141	return rc;
142}
143
144static int pm8xxx_rtc_read_time(struct device *dev, struct rtc_time *tm)
145{
146	int rc;
147	u8 value[NUM_8_BIT_RTC_REGS];
148	unsigned long secs;
149	unsigned int reg;
150	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
 
151
152	rc = regmap_bulk_read(rtc_dd->regmap, rtc_dd->rtc_read_base,
153			      value, sizeof(value));
154	if (rc) {
155		dev_err(dev, "RTC read data register failed\n");
156		return rc;
157	}
158
159	/*
160	 * Read the LSB again and check if there has been a carry over.
161	 * If there is, redo the read operation.
162	 */
163	rc = regmap_read(rtc_dd->regmap, rtc_dd->rtc_read_base, &reg);
164	if (rc < 0) {
165		dev_err(dev, "RTC read data register failed\n");
166		return rc;
167	}
168
169	if (unlikely(reg < value[0])) {
170		rc = regmap_bulk_read(rtc_dd->regmap, rtc_dd->rtc_read_base,
171				      value, sizeof(value));
172		if (rc) {
173			dev_err(dev, "RTC read data register failed\n");
174			return rc;
175		}
176	}
177
178	secs = value[0] | (value[1] << 8) | (value[2] << 16) | (value[3] << 24);
179
180	rtc_time_to_tm(secs, tm);
181
182	rc = rtc_valid_tm(tm);
183	if (rc < 0) {
184		dev_err(dev, "Invalid time read from RTC\n");
185		return rc;
186	}
187
188	dev_dbg(dev, "secs = %lu, h:m:s == %d:%d:%d, d/m/y = %d/%d/%d\n",
189		secs, tm->tm_hour, tm->tm_min, tm->tm_sec,
190		tm->tm_mday, tm->tm_mon, tm->tm_year);
191
192	return 0;
193}
194
195static int pm8xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
196{
197	int rc, i;
198	u8 value[NUM_8_BIT_RTC_REGS], ctrl_reg;
 
199	unsigned long secs, irq_flags;
200	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
 
201
202	rtc_tm_to_time(&alarm->time, &secs);
203
204	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
205		value[i] = secs & 0xFF;
206		secs >>= 8;
207	}
208
209	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
210
211	rc = regmap_bulk_write(rtc_dd->regmap, rtc_dd->alarm_rw_base, value,
212			       sizeof(value));
213	if (rc) {
214		dev_err(dev, "Write to RTC ALARM register failed\n");
215		goto rtc_rw_fail;
216	}
217
218	ctrl_reg = rtc_dd->ctrl_reg;
 
 
219
220	if (alarm->enabled)
221		ctrl_reg |= PM8xxx_RTC_ALARM_ENABLE;
222	else
223		ctrl_reg &= ~PM8xxx_RTC_ALARM_ENABLE;
224
225	rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
226	if (rc) {
227		dev_err(dev, "Write to RTC control register failed\n");
228		goto rtc_rw_fail;
229	}
230
231	rtc_dd->ctrl_reg = ctrl_reg;
232
233	dev_dbg(dev, "Alarm Set for h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",
234		alarm->time.tm_hour, alarm->time.tm_min,
235		alarm->time.tm_sec, alarm->time.tm_mday,
236		alarm->time.tm_mon, alarm->time.tm_year);
237rtc_rw_fail:
238	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
239	return rc;
240}
241
242static int pm8xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
243{
244	int rc;
245	u8 value[NUM_8_BIT_RTC_REGS];
246	unsigned long secs;
247	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
 
248
249	rc = regmap_bulk_read(rtc_dd->regmap, rtc_dd->alarm_rw_base, value,
250			      sizeof(value));
251	if (rc) {
252		dev_err(dev, "RTC alarm time read failed\n");
253		return rc;
254	}
255
256	secs = value[0] | (value[1] << 8) | (value[2] << 16) | (value[3] << 24);
257
258	rtc_time_to_tm(secs, &alarm->time);
259
260	rc = rtc_valid_tm(&alarm->time);
261	if (rc < 0) {
262		dev_err(dev, "Invalid alarm time read from RTC\n");
263		return rc;
264	}
265
266	dev_dbg(dev, "Alarm set for - h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",
267		alarm->time.tm_hour, alarm->time.tm_min,
268		alarm->time.tm_sec, alarm->time.tm_mday,
269		alarm->time.tm_mon, alarm->time.tm_year);
270
271	return 0;
272}
273
274static int pm8xxx_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
275{
276	int rc;
277	unsigned long irq_flags;
278	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
279	u8 ctrl_reg;
 
280
281	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
282
283	ctrl_reg = rtc_dd->ctrl_reg;
 
 
284
285	if (enable)
286		ctrl_reg |= PM8xxx_RTC_ALARM_ENABLE;
287	else
288		ctrl_reg &= ~PM8xxx_RTC_ALARM_ENABLE;
289
290	rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
291	if (rc) {
292		dev_err(dev, "Write to RTC control register failed\n");
293		goto rtc_rw_fail;
294	}
295
296	rtc_dd->ctrl_reg = ctrl_reg;
297
298rtc_rw_fail:
299	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
300	return rc;
301}
302
303static const struct rtc_class_ops pm8xxx_rtc_ops = {
304	.read_time	= pm8xxx_rtc_read_time,
305	.set_time	= pm8xxx_rtc_set_time,
306	.set_alarm	= pm8xxx_rtc_set_alarm,
307	.read_alarm	= pm8xxx_rtc_read_alarm,
308	.alarm_irq_enable = pm8xxx_rtc_alarm_irq_enable,
309};
310
311static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
312{
313	struct pm8xxx_rtc *rtc_dd = dev_id;
 
314	unsigned int ctrl_reg;
315	int rc;
316	unsigned long irq_flags;
317
318	rtc_update_irq(rtc_dd->rtc, 1, RTC_IRQF | RTC_AF);
319
320	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
321
322	/* Clear the alarm enable bit */
323	ctrl_reg = rtc_dd->ctrl_reg;
324	ctrl_reg &= ~PM8xxx_RTC_ALARM_ENABLE;
 
 
 
 
 
325
326	rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
327	if (rc) {
328		spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
329		dev_err(rtc_dd->rtc_dev,
330			"Write to RTC control register failed\n");
331		goto rtc_alarm_handled;
332	}
333
334	rtc_dd->ctrl_reg = ctrl_reg;
335	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
336
337	/* Clear RTC alarm register */
338	rc = regmap_read(rtc_dd->regmap,
339			 rtc_dd->rtc_base + PM8XXX_ALARM_CTRL_OFFSET,
340			 &ctrl_reg);
341	if (rc) {
342		dev_err(rtc_dd->rtc_dev,
343			"RTC Alarm control register read failed\n");
344		goto rtc_alarm_handled;
345	}
346
347	ctrl_reg &= ~PM8xxx_RTC_ALARM_CLEAR;
348	rc = regmap_write(rtc_dd->regmap,
349			  rtc_dd->rtc_base + PM8XXX_ALARM_CTRL_OFFSET,
350			  ctrl_reg);
351	if (rc)
352		dev_err(rtc_dd->rtc_dev,
353			"Write to RTC Alarm control register failed\n");
354
355rtc_alarm_handled:
356	return IRQ_HANDLED;
357}
358
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
359/*
360 * Hardcoded RTC bases until IORESOURCE_REG mapping is figured out
361 */
362static const struct of_device_id pm8xxx_id_table[] = {
363	{ .compatible = "qcom,pm8921-rtc", .data = (void *) 0x11D },
364	{ .compatible = "qcom,pm8058-rtc", .data = (void *) 0x1E8 },
 
365	{ },
366};
367MODULE_DEVICE_TABLE(of, pm8xxx_id_table);
368
369static int pm8xxx_rtc_probe(struct platform_device *pdev)
370{
371	int rc;
372	unsigned int ctrl_reg;
373	struct pm8xxx_rtc *rtc_dd;
374	const struct of_device_id *match;
375
376	match = of_match_node(pm8xxx_id_table, pdev->dev.of_node);
377	if (!match)
378		return -ENXIO;
379
380	rtc_dd = devm_kzalloc(&pdev->dev, sizeof(*rtc_dd), GFP_KERNEL);
381	if (rtc_dd == NULL)
382		return -ENOMEM;
383
384	/* Initialise spinlock to protect RTC control register */
385	spin_lock_init(&rtc_dd->ctrl_reg_lock);
386
387	rtc_dd->regmap = dev_get_regmap(pdev->dev.parent, NULL);
388	if (!rtc_dd->regmap) {
389		dev_err(&pdev->dev, "Parent regmap unavailable.\n");
390		return -ENXIO;
391	}
392
393	rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 0);
394	if (rtc_dd->rtc_alarm_irq < 0) {
395		dev_err(&pdev->dev, "Alarm IRQ resource absent!\n");
396		return -ENXIO;
397	}
398
399	rtc_dd->allow_set_time = of_property_read_bool(pdev->dev.of_node,
400						      "allow-set-time");
401
402	rtc_dd->rtc_base = (long) match->data;
403
404	/* Setup RTC register addresses */
405	rtc_dd->rtc_write_base = rtc_dd->rtc_base + PM8XXX_RTC_WRITE_OFFSET;
406	rtc_dd->rtc_read_base = rtc_dd->rtc_base + PM8XXX_RTC_READ_OFFSET;
407	rtc_dd->alarm_rw_base = rtc_dd->rtc_base + PM8XXX_ALARM_RW_OFFSET;
408
409	rtc_dd->rtc_dev = &pdev->dev;
410
411	/* Check if the RTC is on, else turn it on */
412	rc = regmap_read(rtc_dd->regmap, rtc_dd->rtc_base, &ctrl_reg);
413	if (rc) {
414		dev_err(&pdev->dev, "RTC control register read failed!\n");
415		return rc;
416	}
417
418	if (!(ctrl_reg & PM8xxx_RTC_ENABLE)) {
419		ctrl_reg |= PM8xxx_RTC_ENABLE;
420		rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
421		if (rc) {
422			dev_err(&pdev->dev,
423				"Write to RTC control register failed\n");
424			return rc;
425		}
426	}
427
428	rtc_dd->ctrl_reg = ctrl_reg;
429
430	platform_set_drvdata(pdev, rtc_dd);
431
432	device_init_wakeup(&pdev->dev, 1);
433
434	/* Register the RTC device */
435	rtc_dd->rtc = devm_rtc_device_register(&pdev->dev, "pm8xxx_rtc",
436					       &pm8xxx_rtc_ops, THIS_MODULE);
437	if (IS_ERR(rtc_dd->rtc)) {
438		dev_err(&pdev->dev, "%s: RTC registration failed (%ld)\n",
439			__func__, PTR_ERR(rtc_dd->rtc));
440		return PTR_ERR(rtc_dd->rtc);
441	}
442
443	/* Request the alarm IRQ */
444	rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->rtc_alarm_irq,
445					  pm8xxx_alarm_trigger,
446					  IRQF_TRIGGER_RISING,
447					  "pm8xxx_rtc_alarm", rtc_dd);
448	if (rc < 0) {
449		dev_err(&pdev->dev, "Request IRQ failed (%d)\n", rc);
450		return rc;
451	}
452
453	dev_dbg(&pdev->dev, "Probe success !!\n");
454
455	return 0;
456}
457
458#ifdef CONFIG_PM_SLEEP
459static int pm8xxx_rtc_resume(struct device *dev)
460{
461	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
462
463	if (device_may_wakeup(dev))
464		disable_irq_wake(rtc_dd->rtc_alarm_irq);
465
466	return 0;
467}
468
469static int pm8xxx_rtc_suspend(struct device *dev)
470{
471	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
472
473	if (device_may_wakeup(dev))
474		enable_irq_wake(rtc_dd->rtc_alarm_irq);
475
476	return 0;
477}
478#endif
479
480static SIMPLE_DEV_PM_OPS(pm8xxx_rtc_pm_ops,
481			 pm8xxx_rtc_suspend,
482			 pm8xxx_rtc_resume);
483
484static struct platform_driver pm8xxx_rtc_driver = {
485	.probe		= pm8xxx_rtc_probe,
486	.driver	= {
487		.name		= "rtc-pm8xxx",
488		.owner		= THIS_MODULE,
489		.pm		= &pm8xxx_rtc_pm_ops,
490		.of_match_table	= pm8xxx_id_table,
491	},
492};
493
494module_platform_driver(pm8xxx_rtc_driver);
495
496MODULE_ALIAS("platform:rtc-pm8xxx");
497MODULE_DESCRIPTION("PMIC8xxx RTC driver");
498MODULE_LICENSE("GPL v2");
499MODULE_AUTHOR("Anirudh Ghayal <aghayal@codeaurora.org>");