xref: /openbmc/linux/drivers/rtc/rtc-88pm80x.c (revision 8ef70a5e)
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 
38 struct 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 
rtc_update_handler(int irq,void * data)47 static 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 
pm80x_rtc_alarm_irq_enable(struct device * dev,unsigned int enabled)59 static 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  */
rtc_next_alarm_time(struct rtc_time * next,struct rtc_time * now,struct rtc_time * alrm)76 static 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 
pm80x_rtc_read_time(struct device * dev,struct rtc_time * tm)99 static 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 
pm80x_rtc_set_time(struct device * dev,struct rtc_time * tm)120 static 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 
pm80x_rtc_read_alarm(struct device * dev,struct rtc_wkalrm * alrm)144 static 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 
pm80x_rtc_set_alarm(struct device * dev,struct rtc_wkalrm * alrm)170 static 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 
217 static 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
pm80x_rtc_suspend(struct device * dev)226 static int pm80x_rtc_suspend(struct device *dev)
227 {
228 	return pm80x_dev_suspend(dev);
229 }
230 
pm80x_rtc_resume(struct device * dev)231 static int pm80x_rtc_resume(struct device *dev)
232 {
233 	return pm80x_dev_resume(dev);
234 }
235 #endif
236 
237 static SIMPLE_DEV_PM_OPS(pm80x_rtc_pm_ops, pm80x_rtc_suspend, pm80x_rtc_resume);
238 
pm80x_rtc_probe(struct platform_device * pdev)239 static 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;
314 out_rtc:
315 	pm80x_free_irq(chip, info->irq, info);
316 out:
317 	return ret;
318 }
319 
pm80x_rtc_remove(struct platform_device * pdev)320 static 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 
326 static 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 
335 module_platform_driver(pm80x_rtc_driver);
336 
337 MODULE_LICENSE("GPL");
338 MODULE_DESCRIPTION("Marvell 88PM80x RTC driver");
339 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
340 MODULE_ALIAS("platform:88pm80x-rtc");
341