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
50struct 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
61static 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
73static 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 */
90static 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
113static 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
132static 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
160static 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
184static 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
229static 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
238static int pm80x_rtc_suspend(struct device *dev)
239{
240	return pm80x_dev_suspend(dev);
241}
242
243static int pm80x_rtc_resume(struct device *dev)
244{
245	return pm80x_dev_resume(dev);
246}
247#endif
248
249static SIMPLE_DEV_PM_OPS(pm80x_rtc_pm_ops, pm80x_rtc_suspend, pm80x_rtc_resume);
250
251static int pm80x_rtc_probe(struct platform_device *pdev)
252{
253	struct pm80x_chip *chip = dev_get_drvdata(pdev->dev.parent);
254	struct pm80x_platform_data *pm80x_pdata =
255				dev_get_platdata(pdev->dev.parent);
256	struct pm80x_rtc_pdata *pdata = NULL;
257	struct pm80x_rtc_info *info;
258	struct rtc_time tm;
259	unsigned long ticks = 0;
260	int ret;
261
262	pdata = dev_get_platdata(&pdev->dev);
263	if (pdata == NULL)
264		dev_warn(&pdev->dev, "No platform data!\n");
265
266	info =
267	    devm_kzalloc(&pdev->dev, sizeof(struct pm80x_rtc_info), GFP_KERNEL);
268	if (!info)
269		return -ENOMEM;
270	info->irq = platform_get_irq(pdev, 0);
271	if (info->irq < 0) {
272		dev_err(&pdev->dev, "No IRQ resource!\n");
273		ret = -EINVAL;
274		goto out;
275	}
276
277	info->chip = chip;
278	info->map = chip->regmap;
279	if (!info->map) {
280		dev_err(&pdev->dev, "no regmap!\n");
281		ret = -EINVAL;
282		goto out;
283	}
284
285	info->dev = &pdev->dev;
286	dev_set_drvdata(&pdev->dev, info);
287
288	ret = pm80x_request_irq(chip, info->irq, rtc_update_handler,
289				IRQF_ONESHOT, "rtc", info);
290	if (ret < 0) {
291		dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
292			info->irq, ret);
293		goto out;
294	}
295
296	ret = pm80x_rtc_read_time(&pdev->dev, &tm);
297	if (ret < 0) {
298		dev_err(&pdev->dev, "Failed to read initial time.\n");
299		goto out_rtc;
300	}
301	if ((tm.tm_year < 70) || (tm.tm_year > 138)) {
302		tm.tm_year = 70;
303		tm.tm_mon = 0;
304		tm.tm_mday = 1;
305		tm.tm_hour = 0;
306		tm.tm_min = 0;
307		tm.tm_sec = 0;
308		ret = pm80x_rtc_set_time(&pdev->dev, &tm);
309		if (ret < 0) {
310			dev_err(&pdev->dev, "Failed to set initial time.\n");
311			goto out_rtc;
312		}
313	}
314	rtc_tm_to_time(&tm, &ticks);
315
316	info->rtc_dev = devm_rtc_device_register(&pdev->dev, "88pm80x-rtc",
317					    &pm80x_rtc_ops, THIS_MODULE);
318	if (IS_ERR(info->rtc_dev)) {
319		ret = PTR_ERR(info->rtc_dev);
320		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
321		goto out_rtc;
322	}
323	/*
324	 * enable internal XO instead of internal 3.25MHz clock since it can
325	 * free running in PMIC power-down state.
326	 */
327	regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_RTC1_USE_XO,
328			   PM800_RTC1_USE_XO);
329
330	if (pm80x_pdata) {
331		pdata = pm80x_pdata->rtc;
332		if (pdata)
333			info->rtc_dev->dev.platform_data = &pdata->rtc_wakeup;
334	}
335
336	device_init_wakeup(&pdev->dev, 1);
337
338	return 0;
339out_rtc:
340	pm80x_free_irq(chip, info->irq, info);
341out:
342	return ret;
343}
344
345static int pm80x_rtc_remove(struct platform_device *pdev)
346{
347	struct pm80x_rtc_info *info = platform_get_drvdata(pdev);
348	pm80x_free_irq(info->chip, info->irq, info);
349	return 0;
350}
351
352static struct platform_driver pm80x_rtc_driver = {
353	.driver = {
354		   .name = "88pm80x-rtc",
355		   .pm = &pm80x_rtc_pm_ops,
356		   },
357	.probe = pm80x_rtc_probe,
358	.remove = pm80x_rtc_remove,
359};
360
361module_platform_driver(pm80x_rtc_driver);
362
363MODULE_LICENSE("GPL");
364MODULE_DESCRIPTION("Marvell 88PM80x RTC driver");
365MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
366MODULE_ALIAS("platform:88pm80x-rtc");
367