1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Real Time Clock driver for Marvell 88PM80x PMIC
4 *
5 * Copyright (c) 2012 Marvell International Ltd.
6 *  Wenzeng Chen<wzch@marvell.com>
7 *  Qiao Zhou <zhouqiao@marvell.com>
8 */
9
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/slab.h>
13#include <linux/regmap.h>
14#include <linux/mfd/core.h>
15#include <linux/mfd/88pm80x.h>
16#include <linux/rtc.h>
17
18#define PM800_RTC_COUNTER1		(0xD1)
19#define PM800_RTC_COUNTER2		(0xD2)
20#define PM800_RTC_COUNTER3		(0xD3)
21#define PM800_RTC_COUNTER4		(0xD4)
22#define PM800_RTC_EXPIRE1_1		(0xD5)
23#define PM800_RTC_EXPIRE1_2		(0xD6)
24#define PM800_RTC_EXPIRE1_3		(0xD7)
25#define PM800_RTC_EXPIRE1_4		(0xD8)
26#define PM800_RTC_TRIM1			(0xD9)
27#define PM800_RTC_TRIM2			(0xDA)
28#define PM800_RTC_TRIM3			(0xDB)
29#define PM800_RTC_TRIM4			(0xDC)
30#define PM800_RTC_EXPIRE2_1		(0xDD)
31#define PM800_RTC_EXPIRE2_2		(0xDE)
32#define PM800_RTC_EXPIRE2_3		(0xDF)
33#define PM800_RTC_EXPIRE2_4		(0xE0)
34
35#define PM800_POWER_DOWN_LOG1	(0xE5)
36#define PM800_POWER_DOWN_LOG2	(0xE6)
37
38struct pm80x_rtc_info {
39	struct pm80x_chip *chip;
40	struct regmap *map;
41	struct rtc_device *rtc_dev;
42	struct device *dev;
43
44	int irq;
45};
46
47static irqreturn_t rtc_update_handler(int irq, void *data)
48{
49	struct pm80x_rtc_info *info = (struct pm80x_rtc_info *)data;
50	int mask;
51
52	mask = PM800_ALARM | PM800_ALARM_WAKEUP;
53	regmap_update_bits(info->map, PM800_RTC_CONTROL, mask | PM800_ALARM1_EN,
54			   mask);
55	rtc_update_irq(info->rtc_dev, 1, RTC_AF);
56	return IRQ_HANDLED;
57}
58
59static int pm80x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
60{
61	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
62
63	if (enabled)
64		regmap_update_bits(info->map, PM800_RTC_CONTROL,
65				   PM800_ALARM1_EN, PM800_ALARM1_EN);
66	else
67		regmap_update_bits(info->map, PM800_RTC_CONTROL,
68				   PM800_ALARM1_EN, 0);
69	return 0;
70}
71
72/*
73 * Calculate the next alarm time given the requested alarm time mask
74 * and the current time.
75 */
76static void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now,
77				struct rtc_time *alrm)
78{
79	unsigned long next_time;
80	unsigned long now_time;
81
82	next->tm_year = now->tm_year;
83	next->tm_mon = now->tm_mon;
84	next->tm_mday = now->tm_mday;
85	next->tm_hour = alrm->tm_hour;
86	next->tm_min = alrm->tm_min;
87	next->tm_sec = alrm->tm_sec;
88
89	now_time = rtc_tm_to_time64(now);
90	next_time = rtc_tm_to_time64(next);
91
92	if (next_time < now_time) {
93		/* Advance one day */
94		next_time += 60 * 60 * 24;
95		rtc_time64_to_tm(next_time, next);
96	}
97}
98
99static int pm80x_rtc_read_time(struct device *dev, struct rtc_time *tm)
100{
101	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
102	unsigned char buf[4];
103	unsigned long ticks, base, data;
104	regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
105	base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
106		(buf[1] << 8) | buf[0];
107	dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
108
109	/* load 32-bit read-only counter */
110	regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
111	data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
112		(buf[1] << 8) | buf[0];
113	ticks = base + data;
114	dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
115		base, data, ticks);
116	rtc_time64_to_tm(ticks, tm);
117	return 0;
118}
119
120static int pm80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
121{
122	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
123	unsigned char buf[4];
124	unsigned long ticks, base, data;
125
126	ticks = rtc_tm_to_time64(tm);
127
128	/* load 32-bit read-only counter */
129	regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
130	data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
131		(buf[1] << 8) | buf[0];
132	base = ticks - data;
133	dev_dbg(info->dev, "set base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
134		base, data, ticks);
135	buf[0] = base & 0xFF;
136	buf[1] = (base >> 8) & 0xFF;
137	buf[2] = (base >> 16) & 0xFF;
138	buf[3] = (base >> 24) & 0xFF;
139	regmap_raw_write(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
140
141	return 0;
142}
143
144static int pm80x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
145{
146	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
147	unsigned char buf[4];
148	unsigned long ticks, base, data;
149	int ret;
150
151	regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
152	base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
153		(buf[1] << 8) | buf[0];
154	dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
155
156	regmap_raw_read(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
157	data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
158		(buf[1] << 8) | buf[0];
159	ticks = base + data;
160	dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
161		base, data, ticks);
162
163	rtc_time64_to_tm(ticks, &alrm->time);
164	regmap_read(info->map, PM800_RTC_CONTROL, &ret);
165	alrm->enabled = (ret & PM800_ALARM1_EN) ? 1 : 0;
166	alrm->pending = (ret & (PM800_ALARM | PM800_ALARM_WAKEUP)) ? 1 : 0;
167	return 0;
168}
169
170static int pm80x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
171{
172	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
173	struct rtc_time now_tm, alarm_tm;
174	unsigned long ticks, base, data;
175	unsigned char buf[4];
176	int mask;
177
178	regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_ALARM1_EN, 0);
179
180	regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
181	base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
182		(buf[1] << 8) | buf[0];
183	dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
184
185	/* load 32-bit read-only counter */
186	regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
187	data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
188		(buf[1] << 8) | buf[0];
189	ticks = base + data;
190	dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
191		base, data, ticks);
192
193	rtc_time64_to_tm(ticks, &now_tm);
194	dev_dbg(info->dev, "%s, now time : %lu\n", __func__, ticks);
195	rtc_next_alarm_time(&alarm_tm, &now_tm, &alrm->time);
196	/* get new ticks for alarm in 24 hours */
197	ticks = rtc_tm_to_time64(&alarm_tm);
198	dev_dbg(info->dev, "%s, alarm time: %lu\n", __func__, ticks);
199	data = ticks - base;
200
201	buf[0] = data & 0xff;
202	buf[1] = (data >> 8) & 0xff;
203	buf[2] = (data >> 16) & 0xff;
204	buf[3] = (data >> 24) & 0xff;
205	regmap_raw_write(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
206	if (alrm->enabled) {
207		mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
208		regmap_update_bits(info->map, PM800_RTC_CONTROL, mask, mask);
209	} else {
210		mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
211		regmap_update_bits(info->map, PM800_RTC_CONTROL, mask,
212				   PM800_ALARM | PM800_ALARM_WAKEUP);
213	}
214	return 0;
215}
216
217static const struct rtc_class_ops pm80x_rtc_ops = {
218	.read_time = pm80x_rtc_read_time,
219	.set_time = pm80x_rtc_set_time,
220	.read_alarm = pm80x_rtc_read_alarm,
221	.set_alarm = pm80x_rtc_set_alarm,
222	.alarm_irq_enable = pm80x_rtc_alarm_irq_enable,
223};
224
225#ifdef CONFIG_PM_SLEEP
226static int pm80x_rtc_suspend(struct device *dev)
227{
228	return pm80x_dev_suspend(dev);
229}
230
231static int pm80x_rtc_resume(struct device *dev)
232{
233	return pm80x_dev_resume(dev);
234}
235#endif
236
237static SIMPLE_DEV_PM_OPS(pm80x_rtc_pm_ops, pm80x_rtc_suspend, pm80x_rtc_resume);
238
239static int pm80x_rtc_probe(struct platform_device *pdev)
240{
241	struct pm80x_chip *chip = dev_get_drvdata(pdev->dev.parent);
242	struct pm80x_rtc_pdata *pdata = dev_get_platdata(&pdev->dev);
243	struct pm80x_rtc_info *info;
244	struct device_node *node = pdev->dev.of_node;
245	int ret;
246
247	if (!pdata && !node) {
248		dev_err(&pdev->dev,
249			"pm80x-rtc requires platform data or of_node\n");
250		return -EINVAL;
251	}
252
253	if (!pdata) {
254		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
255		if (!pdata) {
256			dev_err(&pdev->dev, "failed to allocate memory\n");
257			return -ENOMEM;
258		}
259	}
260
261	info =
262	    devm_kzalloc(&pdev->dev, sizeof(struct pm80x_rtc_info), GFP_KERNEL);
263	if (!info)
264		return -ENOMEM;
265	info->irq = platform_get_irq(pdev, 0);
266	if (info->irq < 0) {
267		ret = -EINVAL;
268		goto out;
269	}
270
271	info->chip = chip;
272	info->map = chip->regmap;
273	if (!info->map) {
274		dev_err(&pdev->dev, "no regmap!\n");
275		ret = -EINVAL;
276		goto out;
277	}
278
279	info->dev = &pdev->dev;
280	dev_set_drvdata(&pdev->dev, info);
281
282	info->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
283	if (IS_ERR(info->rtc_dev))
284		return PTR_ERR(info->rtc_dev);
285
286	ret = pm80x_request_irq(chip, info->irq, rtc_update_handler,
287				IRQF_ONESHOT, "rtc", info);
288	if (ret < 0) {
289		dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
290			info->irq, ret);
291		goto out;
292	}
293
294	info->rtc_dev->ops = &pm80x_rtc_ops;
295	info->rtc_dev->range_max = U32_MAX;
296
297	ret = devm_rtc_register_device(info->rtc_dev);
298	if (ret)
299		goto out_rtc;
300
301	/*
302	 * enable internal XO instead of internal 3.25MHz clock since it can
303	 * free running in PMIC power-down state.
304	 */
305	regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_RTC1_USE_XO,
306			   PM800_RTC1_USE_XO);
307
308	/* remember whether this power up is caused by PMIC RTC or not */
309	info->rtc_dev->dev.platform_data = &pdata->rtc_wakeup;
310
311	device_init_wakeup(&pdev->dev, 1);
312
313	return 0;
314out_rtc:
315	pm80x_free_irq(chip, info->irq, info);
316out:
317	return ret;
318}
319
320static void pm80x_rtc_remove(struct platform_device *pdev)
321{
322	struct pm80x_rtc_info *info = platform_get_drvdata(pdev);
323	pm80x_free_irq(info->chip, info->irq, info);
324}
325
326static struct platform_driver pm80x_rtc_driver = {
327	.driver = {
328		   .name = "88pm80x-rtc",
329		   .pm = &pm80x_rtc_pm_ops,
330		   },
331	.probe = pm80x_rtc_probe,
332	.remove_new = pm80x_rtc_remove,
333};
334
335module_platform_driver(pm80x_rtc_driver);
336
337MODULE_LICENSE("GPL");
338MODULE_DESCRIPTION("Marvell 88PM80x RTC driver");
339MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
340MODULE_ALIAS("platform:88pm80x-rtc");
341