xref: /openbmc/linux/drivers/rtc/rtc-88pm80x.c (revision 3557b3fd)
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 
56 	int irq;
57 };
58 
59 static irqreturn_t rtc_update_handler(int irq, void *data)
60 {
61 	struct pm80x_rtc_info *info = (struct pm80x_rtc_info *)data;
62 	int mask;
63 
64 	mask = PM800_ALARM | PM800_ALARM_WAKEUP;
65 	regmap_update_bits(info->map, PM800_RTC_CONTROL, mask | PM800_ALARM1_EN,
66 			   mask);
67 	rtc_update_irq(info->rtc_dev, 1, RTC_AF);
68 	return IRQ_HANDLED;
69 }
70 
71 static int pm80x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
72 {
73 	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
74 
75 	if (enabled)
76 		regmap_update_bits(info->map, PM800_RTC_CONTROL,
77 				   PM800_ALARM1_EN, PM800_ALARM1_EN);
78 	else
79 		regmap_update_bits(info->map, PM800_RTC_CONTROL,
80 				   PM800_ALARM1_EN, 0);
81 	return 0;
82 }
83 
84 /*
85  * Calculate the next alarm time given the requested alarm time mask
86  * and the current time.
87  */
88 static void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now,
89 				struct rtc_time *alrm)
90 {
91 	unsigned long next_time;
92 	unsigned long now_time;
93 
94 	next->tm_year = now->tm_year;
95 	next->tm_mon = now->tm_mon;
96 	next->tm_mday = now->tm_mday;
97 	next->tm_hour = alrm->tm_hour;
98 	next->tm_min = alrm->tm_min;
99 	next->tm_sec = alrm->tm_sec;
100 
101 	now_time = rtc_tm_to_time64(now);
102 	next_time = rtc_tm_to_time64(next);
103 
104 	if (next_time < now_time) {
105 		/* Advance one day */
106 		next_time += 60 * 60 * 24;
107 		rtc_time64_to_tm(next_time, next);
108 	}
109 }
110 
111 static int pm80x_rtc_read_time(struct device *dev, struct rtc_time *tm)
112 {
113 	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
114 	unsigned char buf[4];
115 	unsigned long ticks, base, data;
116 	regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
117 	base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
118 		(buf[1] << 8) | buf[0];
119 	dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
120 
121 	/* load 32-bit read-only counter */
122 	regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
123 	data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
124 		(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_time64_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 
138 	ticks = rtc_tm_to_time64(tm);
139 
140 	/* load 32-bit read-only counter */
141 	regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
142 	data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
143 		(buf[1] << 8) | buf[0];
144 	base = ticks - data;
145 	dev_dbg(info->dev, "set base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
146 		base, data, ticks);
147 	buf[0] = base & 0xFF;
148 	buf[1] = (base >> 8) & 0xFF;
149 	buf[2] = (base >> 16) & 0xFF;
150 	buf[3] = (base >> 24) & 0xFF;
151 	regmap_raw_write(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
152 
153 	return 0;
154 }
155 
156 static int pm80x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
157 {
158 	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
159 	unsigned char buf[4];
160 	unsigned long ticks, base, data;
161 	int ret;
162 
163 	regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
164 	base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
165 		(buf[1] << 8) | buf[0];
166 	dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
167 
168 	regmap_raw_read(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
169 	data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
170 		(buf[1] << 8) | buf[0];
171 	ticks = base + data;
172 	dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
173 		base, data, ticks);
174 
175 	rtc_time64_to_tm(ticks, &alrm->time);
176 	regmap_read(info->map, PM800_RTC_CONTROL, &ret);
177 	alrm->enabled = (ret & PM800_ALARM1_EN) ? 1 : 0;
178 	alrm->pending = (ret & (PM800_ALARM | PM800_ALARM_WAKEUP)) ? 1 : 0;
179 	return 0;
180 }
181 
182 static int pm80x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
183 {
184 	struct pm80x_rtc_info *info = dev_get_drvdata(dev);
185 	struct rtc_time now_tm, alarm_tm;
186 	unsigned long ticks, base, data;
187 	unsigned char buf[4];
188 	int mask;
189 
190 	regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_ALARM1_EN, 0);
191 
192 	regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
193 	base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
194 		(buf[1] << 8) | buf[0];
195 	dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
196 
197 	/* load 32-bit read-only counter */
198 	regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
199 	data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
200 		(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_time64_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 	ticks = rtc_tm_to_time64(&alarm_tm);
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 	int ret;
258 
259 	if (!pdata && !node) {
260 		dev_err(&pdev->dev,
261 			"pm80x-rtc requires platform data or of_node\n");
262 		return -EINVAL;
263 	}
264 
265 	if (!pdata) {
266 		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
267 		if (!pdata) {
268 			dev_err(&pdev->dev, "failed to allocate memory\n");
269 			return -ENOMEM;
270 		}
271 	}
272 
273 	info =
274 	    devm_kzalloc(&pdev->dev, sizeof(struct pm80x_rtc_info), GFP_KERNEL);
275 	if (!info)
276 		return -ENOMEM;
277 	info->irq = platform_get_irq(pdev, 0);
278 	if (info->irq < 0) {
279 		dev_err(&pdev->dev, "No IRQ resource!\n");
280 		ret = -EINVAL;
281 		goto out;
282 	}
283 
284 	info->chip = chip;
285 	info->map = chip->regmap;
286 	if (!info->map) {
287 		dev_err(&pdev->dev, "no regmap!\n");
288 		ret = -EINVAL;
289 		goto out;
290 	}
291 
292 	info->dev = &pdev->dev;
293 	dev_set_drvdata(&pdev->dev, info);
294 
295 	info->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
296 	if (IS_ERR(info->rtc_dev))
297 		return PTR_ERR(info->rtc_dev);
298 
299 	ret = pm80x_request_irq(chip, info->irq, rtc_update_handler,
300 				IRQF_ONESHOT, "rtc", info);
301 	if (ret < 0) {
302 		dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
303 			info->irq, ret);
304 		goto out;
305 	}
306 
307 	info->rtc_dev->ops = &pm80x_rtc_ops;
308 	info->rtc_dev->range_max = U32_MAX;
309 
310 	ret = rtc_register_device(info->rtc_dev);
311 	if (ret) {
312 		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
313 		goto out_rtc;
314 	}
315 	/*
316 	 * enable internal XO instead of internal 3.25MHz clock since it can
317 	 * free running in PMIC power-down state.
318 	 */
319 	regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_RTC1_USE_XO,
320 			   PM800_RTC1_USE_XO);
321 
322 	/* remember whether this power up is caused by PMIC RTC or not */
323 	info->rtc_dev->dev.platform_data = &pdata->rtc_wakeup;
324 
325 	device_init_wakeup(&pdev->dev, 1);
326 
327 	return 0;
328 out_rtc:
329 	pm80x_free_irq(chip, info->irq, info);
330 out:
331 	return ret;
332 }
333 
334 static int pm80x_rtc_remove(struct platform_device *pdev)
335 {
336 	struct pm80x_rtc_info *info = platform_get_drvdata(pdev);
337 	pm80x_free_irq(info->chip, info->irq, info);
338 	return 0;
339 }
340 
341 static struct platform_driver pm80x_rtc_driver = {
342 	.driver = {
343 		   .name = "88pm80x-rtc",
344 		   .pm = &pm80x_rtc_pm_ops,
345 		   },
346 	.probe = pm80x_rtc_probe,
347 	.remove = pm80x_rtc_remove,
348 };
349 
350 module_platform_driver(pm80x_rtc_driver);
351 
352 MODULE_LICENSE("GPL");
353 MODULE_DESCRIPTION("Marvell 88PM80x RTC driver");
354 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
355 MODULE_ALIAS("platform:88pm80x-rtc");
356