xref: /openbmc/linux/drivers/rtc/rtc-88pm80x.c (revision f3539c12)
1 /*
2  * Real Time Clock driver for Marvell 88PM80x PMIC
3  *
4  * Copyright (c) 2012 Marvell International Ltd.
5  *  Wenzeng Chen<wzch@marvell.com>
6  *  Qiao Zhou <zhouqiao@marvell.com>
7  *
8  * This file is subject to the terms and conditions of the GNU General
9  * Public License. See the file "COPYING" in the main directory of this
10  * archive for more details.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21 
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/slab.h>
25 #include <linux/regmap.h>
26 #include <linux/mfd/core.h>
27 #include <linux/mfd/88pm80x.h>
28 #include <linux/rtc.h>
29 
30 #define PM800_RTC_COUNTER1		(0xD1)
31 #define PM800_RTC_COUNTER2		(0xD2)
32 #define PM800_RTC_COUNTER3		(0xD3)
33 #define PM800_RTC_COUNTER4		(0xD4)
34 #define PM800_RTC_EXPIRE1_1		(0xD5)
35 #define PM800_RTC_EXPIRE1_2		(0xD6)
36 #define PM800_RTC_EXPIRE1_3		(0xD7)
37 #define PM800_RTC_EXPIRE1_4		(0xD8)
38 #define PM800_RTC_TRIM1			(0xD9)
39 #define PM800_RTC_TRIM2			(0xDA)
40 #define PM800_RTC_TRIM3			(0xDB)
41 #define PM800_RTC_TRIM4			(0xDC)
42 #define PM800_RTC_EXPIRE2_1		(0xDD)
43 #define PM800_RTC_EXPIRE2_2		(0xDE)
44 #define PM800_RTC_EXPIRE2_3		(0xDF)
45 #define PM800_RTC_EXPIRE2_4		(0xE0)
46 
47 #define PM800_POWER_DOWN_LOG1	(0xE5)
48 #define PM800_POWER_DOWN_LOG2	(0xE6)
49 
50 struct pm80x_rtc_info {
51 	struct pm80x_chip *chip;
52 	struct regmap *map;
53 	struct rtc_device *rtc_dev;
54 	struct device *dev;
55 	struct delayed_work calib_work;
56 
57 	int irq;
58 	int vrtc;
59 };
60 
61 static irqreturn_t rtc_update_handler(int irq, void *data)
62 {
63 	struct pm80x_rtc_info *info = (struct pm80x_rtc_info *)data;
64 	int mask;
65 
66 	mask = PM800_ALARM | PM800_ALARM_WAKEUP;
67 	regmap_update_bits(info->map, PM800_RTC_CONTROL, mask | PM800_ALARM1_EN,
68 			   mask);
69 	rtc_update_irq(info->rtc_dev, 1, RTC_AF);
70 	return IRQ_HANDLED;
71 }
72 
73 static int pm80x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
74 {
75 	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
76 
77 	if (enabled)
78 		regmap_update_bits(info->map, PM800_RTC_CONTROL,
79 				   PM800_ALARM1_EN, PM800_ALARM1_EN);
80 	else
81 		regmap_update_bits(info->map, PM800_RTC_CONTROL,
82 				   PM800_ALARM1_EN, 0);
83 	return 0;
84 }
85 
86 /*
87  * Calculate the next alarm time given the requested alarm time mask
88  * and the current time.
89  */
90 static void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now,
91 				struct rtc_time *alrm)
92 {
93 	unsigned long next_time;
94 	unsigned long now_time;
95 
96 	next->tm_year = now->tm_year;
97 	next->tm_mon = now->tm_mon;
98 	next->tm_mday = now->tm_mday;
99 	next->tm_hour = alrm->tm_hour;
100 	next->tm_min = alrm->tm_min;
101 	next->tm_sec = alrm->tm_sec;
102 
103 	rtc_tm_to_time(now, &now_time);
104 	rtc_tm_to_time(next, &next_time);
105 
106 	if (next_time < now_time) {
107 		/* Advance one day */
108 		next_time += 60 * 60 * 24;
109 		rtc_time_to_tm(next_time, next);
110 	}
111 }
112 
113 static int pm80x_rtc_read_time(struct device *dev, struct rtc_time *tm)
114 {
115 	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
116 	unsigned char buf[4];
117 	unsigned long ticks, base, data;
118 	regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
119 	base = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
120 	dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
121 
122 	/* load 32-bit read-only counter */
123 	regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
124 	data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
125 	ticks = base + data;
126 	dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
127 		base, data, ticks);
128 	rtc_time_to_tm(ticks, tm);
129 	return 0;
130 }
131 
132 static int pm80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
133 {
134 	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
135 	unsigned char buf[4];
136 	unsigned long ticks, base, data;
137 	if ((tm->tm_year < 70) || (tm->tm_year > 138)) {
138 		dev_dbg(info->dev,
139 			"Set time %d out of range. Please set time between 1970 to 2038.\n",
140 			1900 + tm->tm_year);
141 		return -EINVAL;
142 	}
143 	rtc_tm_to_time(tm, &ticks);
144 
145 	/* load 32-bit read-only counter */
146 	regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
147 	data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
148 	base = ticks - data;
149 	dev_dbg(info->dev, "set base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
150 		base, data, ticks);
151 	buf[0] = base & 0xFF;
152 	buf[1] = (base >> 8) & 0xFF;
153 	buf[2] = (base >> 16) & 0xFF;
154 	buf[3] = (base >> 24) & 0xFF;
155 	regmap_raw_write(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
156 
157 	return 0;
158 }
159 
160 static int pm80x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
161 {
162 	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
163 	unsigned char buf[4];
164 	unsigned long ticks, base, data;
165 	int ret;
166 
167 	regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
168 	base = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
169 	dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
170 
171 	regmap_raw_read(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
172 	data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
173 	ticks = base + data;
174 	dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
175 		base, data, ticks);
176 
177 	rtc_time_to_tm(ticks, &alrm->time);
178 	regmap_read(info->map, PM800_RTC_CONTROL, &ret);
179 	alrm->enabled = (ret & PM800_ALARM1_EN) ? 1 : 0;
180 	alrm->pending = (ret & (PM800_ALARM | PM800_ALARM_WAKEUP)) ? 1 : 0;
181 	return 0;
182 }
183 
184 static int pm80x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
185 {
186 	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
187 	struct rtc_time now_tm, alarm_tm;
188 	unsigned long ticks, base, data;
189 	unsigned char buf[4];
190 	int mask;
191 
192 	regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_ALARM1_EN, 0);
193 
194 	regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
195 	base = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
196 	dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
197 
198 	/* load 32-bit read-only counter */
199 	regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
200 	data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
201 	ticks = base + data;
202 	dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
203 		base, data, ticks);
204 
205 	rtc_time_to_tm(ticks, &now_tm);
206 	dev_dbg(info->dev, "%s, now time : %lu\n", __func__, ticks);
207 	rtc_next_alarm_time(&alarm_tm, &now_tm, &alrm->time);
208 	/* get new ticks for alarm in 24 hours */
209 	rtc_tm_to_time(&alarm_tm, &ticks);
210 	dev_dbg(info->dev, "%s, alarm time: %lu\n", __func__, ticks);
211 	data = ticks - base;
212 
213 	buf[0] = data & 0xff;
214 	buf[1] = (data >> 8) & 0xff;
215 	buf[2] = (data >> 16) & 0xff;
216 	buf[3] = (data >> 24) & 0xff;
217 	regmap_raw_write(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
218 	if (alrm->enabled) {
219 		mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
220 		regmap_update_bits(info->map, PM800_RTC_CONTROL, mask, mask);
221 	} else {
222 		mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
223 		regmap_update_bits(info->map, PM800_RTC_CONTROL, mask,
224 				   PM800_ALARM | PM800_ALARM_WAKEUP);
225 	}
226 	return 0;
227 }
228 
229 static const struct rtc_class_ops pm80x_rtc_ops = {
230 	.read_time = pm80x_rtc_read_time,
231 	.set_time = pm80x_rtc_set_time,
232 	.read_alarm = pm80x_rtc_read_alarm,
233 	.set_alarm = pm80x_rtc_set_alarm,
234 	.alarm_irq_enable = pm80x_rtc_alarm_irq_enable,
235 };
236 
237 #ifdef CONFIG_PM_SLEEP
238 static int pm80x_rtc_suspend(struct device *dev)
239 {
240 	return pm80x_dev_suspend(dev);
241 }
242 
243 static int pm80x_rtc_resume(struct device *dev)
244 {
245 	return pm80x_dev_resume(dev);
246 }
247 #endif
248 
249 static SIMPLE_DEV_PM_OPS(pm80x_rtc_pm_ops, pm80x_rtc_suspend, pm80x_rtc_resume);
250 
251 static int pm80x_rtc_probe(struct platform_device *pdev)
252 {
253 	struct pm80x_chip *chip = dev_get_drvdata(pdev->dev.parent);
254 	struct pm80x_rtc_pdata *pdata = dev_get_platdata(&pdev->dev);
255 	struct pm80x_rtc_info *info;
256 	struct device_node *node = pdev->dev.of_node;
257 	struct rtc_time tm;
258 	unsigned long ticks = 0;
259 	int ret;
260 
261 	if (!pdata && !node) {
262 		dev_err(&pdev->dev,
263 			"pm80x-rtc requires platform data or of_node\n");
264 		return -EINVAL;
265 	}
266 
267 	if (!pdata) {
268 		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
269 		if (!pdata) {
270 			dev_err(&pdev->dev, "failed to allocate memory\n");
271 			return -ENOMEM;
272 		}
273 	}
274 
275 	info =
276 	    devm_kzalloc(&pdev->dev, sizeof(struct pm80x_rtc_info), GFP_KERNEL);
277 	if (!info)
278 		return -ENOMEM;
279 	info->irq = platform_get_irq(pdev, 0);
280 	if (info->irq < 0) {
281 		dev_err(&pdev->dev, "No IRQ resource!\n");
282 		ret = -EINVAL;
283 		goto out;
284 	}
285 
286 	info->chip = chip;
287 	info->map = chip->regmap;
288 	if (!info->map) {
289 		dev_err(&pdev->dev, "no regmap!\n");
290 		ret = -EINVAL;
291 		goto out;
292 	}
293 
294 	info->dev = &pdev->dev;
295 	dev_set_drvdata(&pdev->dev, info);
296 
297 	ret = pm80x_request_irq(chip, info->irq, rtc_update_handler,
298 				IRQF_ONESHOT, "rtc", info);
299 	if (ret < 0) {
300 		dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
301 			info->irq, ret);
302 		goto out;
303 	}
304 
305 	ret = pm80x_rtc_read_time(&pdev->dev, &tm);
306 	if (ret < 0) {
307 		dev_err(&pdev->dev, "Failed to read initial time.\n");
308 		goto out_rtc;
309 	}
310 	if ((tm.tm_year < 70) || (tm.tm_year > 138)) {
311 		tm.tm_year = 70;
312 		tm.tm_mon = 0;
313 		tm.tm_mday = 1;
314 		tm.tm_hour = 0;
315 		tm.tm_min = 0;
316 		tm.tm_sec = 0;
317 		ret = pm80x_rtc_set_time(&pdev->dev, &tm);
318 		if (ret < 0) {
319 			dev_err(&pdev->dev, "Failed to set initial time.\n");
320 			goto out_rtc;
321 		}
322 	}
323 	rtc_tm_to_time(&tm, &ticks);
324 
325 	info->rtc_dev = devm_rtc_device_register(&pdev->dev, "88pm80x-rtc",
326 					    &pm80x_rtc_ops, THIS_MODULE);
327 	if (IS_ERR(info->rtc_dev)) {
328 		ret = PTR_ERR(info->rtc_dev);
329 		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
330 		goto out_rtc;
331 	}
332 	/*
333 	 * enable internal XO instead of internal 3.25MHz clock since it can
334 	 * free running in PMIC power-down state.
335 	 */
336 	regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_RTC1_USE_XO,
337 			   PM800_RTC1_USE_XO);
338 
339 	/* remember whether this power up is caused by PMIC RTC or not */
340 	info->rtc_dev->dev.platform_data = &pdata->rtc_wakeup;
341 
342 	device_init_wakeup(&pdev->dev, 1);
343 
344 	return 0;
345 out_rtc:
346 	pm80x_free_irq(chip, info->irq, info);
347 out:
348 	return ret;
349 }
350 
351 static int pm80x_rtc_remove(struct platform_device *pdev)
352 {
353 	struct pm80x_rtc_info *info = platform_get_drvdata(pdev);
354 	pm80x_free_irq(info->chip, info->irq, info);
355 	return 0;
356 }
357 
358 static struct platform_driver pm80x_rtc_driver = {
359 	.driver = {
360 		   .name = "88pm80x-rtc",
361 		   .pm = &pm80x_rtc_pm_ops,
362 		   },
363 	.probe = pm80x_rtc_probe,
364 	.remove = pm80x_rtc_remove,
365 };
366 
367 module_platform_driver(pm80x_rtc_driver);
368 
369 MODULE_LICENSE("GPL");
370 MODULE_DESCRIPTION("Marvell 88PM80x RTC driver");
371 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
372 MODULE_ALIAS("platform:88pm80x-rtc");
373