1/*
2 * Epson RX8010 RTC driver.
3 *
4 * Copyright (c) 2017, General Electric Company
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
17 */
18
19#include <command.h>
20#include <common.h>
21#include <dm.h>
22#include <i2c.h>
23#include <rtc.h>
24#include <linux/bitops.h>
25
26/*---------------------------------------------------------------------*/
27/* #undef DEBUG_RTC */
28
29#ifdef DEBUG_RTC
30#define DEBUGR(fmt, args...) printf(fmt, ##args)
31#else
32#define DEBUGR(fmt, args...)
33#endif
34/*---------------------------------------------------------------------*/
35
36#ifndef CFG_SYS_I2C_RTC_ADDR
37# define CFG_SYS_I2C_RTC_ADDR	0x32
38#endif
39
40/*
41 * RTC register addresses
42 */
43#define RX8010_SEC     0x10
44#define RX8010_MIN     0x11
45#define RX8010_HOUR    0x12
46#define RX8010_WDAY    0x13
47#define RX8010_MDAY    0x14
48#define RX8010_MONTH   0x15
49#define RX8010_YEAR    0x16
50#define RX8010_YEAR    0x16
51#define RX8010_RESV17  0x17
52#define RX8010_ALMIN   0x18
53#define RX8010_ALHOUR  0x19
54#define RX8010_ALWDAY  0x1A
55#define RX8010_TCOUNT0 0x1B
56#define RX8010_TCOUNT1 0x1C
57#define RX8010_EXT     0x1D
58#define RX8010_FLAG    0x1E
59#define RX8010_CTRL    0x1F
60/* 0x20 to 0x2F are user registers */
61#define RX8010_RESV30  0x30
62#define RX8010_RESV31  0x32
63#define RX8010_IRQ     0x32
64
65#define RX8010_EXT_WADA  BIT(3)
66
67#define RX8010_FLAG_VLF  BIT(1)
68#define RX8010_FLAG_AF   BIT(3)
69#define RX8010_FLAG_TF   BIT(4)
70#define RX8010_FLAG_UF   BIT(5)
71
72#define RX8010_CTRL_AIE  BIT(3)
73#define RX8010_CTRL_UIE  BIT(5)
74#define RX8010_CTRL_STOP BIT(6)
75#define RX8010_CTRL_TEST BIT(7)
76
77#define RX8010_ALARM_AE  BIT(7)
78
79#ifdef CONFIG_DM_RTC
80
81#define DEV_TYPE struct udevice
82
83#else
84
85/* Local udevice */
86struct ludevice {
87	u8 chip;
88};
89
90#define DEV_TYPE struct ludevice
91
92#endif
93
94static int rx8010sj_rtc_read8(DEV_TYPE *dev, unsigned int reg)
95{
96	u8 val;
97	int ret;
98
99#ifdef CONFIG_DM_RTC
100	ret = dm_i2c_read(dev, reg, &val, sizeof(val));
101#else
102	ret = i2c_read(dev->chip, reg, 1, &val, 1);
103#endif
104
105	return ret < 0 ? ret : val;
106}
107
108static int rx8010sj_rtc_write8(DEV_TYPE *dev, unsigned int reg, int val)
109{
110	int ret;
111	u8 lval = val;
112
113#ifdef CONFIG_DM_RTC
114	ret = dm_i2c_write(dev, reg, &lval, 1);
115#else
116	ret = i2c_write(dev->chip, reg, 1, &lval, 1);
117#endif
118
119	return ret < 0 ? ret : 0;
120}
121
122static int validate_time(const struct rtc_time *tm)
123{
124	if ((tm->tm_year < 2000) || (tm->tm_year > 2099))
125		return -EINVAL;
126
127	if ((tm->tm_mon < 1) || (tm->tm_mon > 12))
128		return -EINVAL;
129
130	if ((tm->tm_mday < 1) || (tm->tm_mday > 31))
131		return -EINVAL;
132
133	if ((tm->tm_wday < 0) || (tm->tm_wday > 6))
134		return -EINVAL;
135
136	if ((tm->tm_hour < 0) || (tm->tm_hour > 23))
137		return -EINVAL;
138
139	if ((tm->tm_min < 0) || (tm->tm_min > 59))
140		return -EINVAL;
141
142	if ((tm->tm_sec < 0) || (tm->tm_sec > 59))
143		return -EINVAL;
144
145	return 0;
146}
147
148void rx8010sj_rtc_init(DEV_TYPE *dev)
149{
150	u8 ctrl[2];
151	int need_clear = 0, ret = 0;
152
153	/* Initialize reserved registers as specified in datasheet */
154	ret = rx8010sj_rtc_write8(dev, RX8010_RESV17, 0xD8);
155	if (ret < 0)
156		goto error;
157
158	ret = rx8010sj_rtc_write8(dev, RX8010_RESV30, 0x00);
159	if (ret < 0)
160		goto error;
161
162	ret = rx8010sj_rtc_write8(dev, RX8010_RESV31, 0x08);
163	if (ret < 0)
164		goto error;
165
166	ret = rx8010sj_rtc_write8(dev, RX8010_IRQ, 0x00);
167	if (ret < 0)
168		goto error;
169
170	for (int i = 0; i < 2; i++) {
171		ret = rx8010sj_rtc_read8(dev, RX8010_FLAG + i);
172		if (ret < 0)
173			goto error;
174
175		ctrl[i] = ret;
176	}
177
178	if (ctrl[0] & RX8010_FLAG_VLF)
179		printf("RTC low voltage detected\n");
180
181	if (ctrl[0] & RX8010_FLAG_AF) {
182		printf("Alarm was detected\n");
183		need_clear = 1;
184	}
185
186	if (ctrl[0] & RX8010_FLAG_TF)
187		need_clear = 1;
188
189	if (ctrl[0] & RX8010_FLAG_UF)
190		need_clear = 1;
191
192	if (need_clear) {
193		ctrl[0] &= ~(RX8010_FLAG_AF | RX8010_FLAG_TF | RX8010_FLAG_UF);
194		ret = rx8010sj_rtc_write8(dev, RX8010_FLAG, ctrl[0]);
195		if (ret < 0)
196			goto error;
197	}
198
199	return;
200
201error:
202	printf("Error rtc init.\n");
203}
204
205/* Get the current time from the RTC */
206static int rx8010sj_rtc_get(DEV_TYPE *dev, struct rtc_time *tmp)
207{
208	u8 date[7];
209	int flagreg;
210	int ret;
211
212	flagreg = rx8010sj_rtc_read8(dev, RX8010_FLAG);
213	if (flagreg < 0) {
214		DEBUGR("Error reading from RTC. err: %d\n", flagreg);
215		return -EIO;
216	}
217
218	if (flagreg & RX8010_FLAG_VLF) {
219		DEBUGR("RTC low voltage detected\n");
220		return -EINVAL;
221	}
222
223	for (int i = 0; i < 7; i++) {
224		ret = rx8010sj_rtc_read8(dev, RX8010_SEC + i);
225		if (ret < 0) {
226			DEBUGR("Error reading from RTC. err: %d\n", ret);
227			return -EIO;
228		}
229		date[i] = ret;
230	}
231
232	tmp->tm_sec = bcd2bin(date[RX8010_SEC - RX8010_SEC] & 0x7f);
233	tmp->tm_min = bcd2bin(date[RX8010_MIN - RX8010_SEC] & 0x7f);
234	tmp->tm_hour = bcd2bin(date[RX8010_HOUR - RX8010_SEC] & 0x3f);
235	tmp->tm_mday = bcd2bin(date[RX8010_MDAY - RX8010_SEC] & 0x3f);
236	tmp->tm_mon = bcd2bin(date[RX8010_MONTH - RX8010_SEC] & 0x1f);
237	tmp->tm_year = bcd2bin(date[RX8010_YEAR - RX8010_SEC]) + 2000;
238	tmp->tm_wday = 0;
239	tmp->tm_yday = 0;
240	tmp->tm_isdst = 0;
241
242	DEBUGR("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
243	       tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
244	       tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
245
246	return 0;
247}
248
249/* Set the RTC */
250static int rx8010sj_rtc_set(DEV_TYPE *dev, const struct rtc_time *tm)
251{
252	u8 date[7];
253	int ctrl, flagreg;
254	int ret;
255
256	ret = validate_time(tm);
257	if (ret < 0)
258		return -EINVAL;
259
260	/* set STOP bit before changing clock/calendar */
261	ctrl = rx8010sj_rtc_read8(dev, RX8010_CTRL);
262	if (ctrl < 0)
263		return ctrl;
264	ret = rx8010sj_rtc_write8(dev, RX8010_CTRL, ctrl | RX8010_CTRL_STOP);
265	if (ret < 0)
266		return ret;
267
268	date[RX8010_SEC - RX8010_SEC] = bin2bcd(tm->tm_sec);
269	date[RX8010_MIN - RX8010_SEC] = bin2bcd(tm->tm_min);
270	date[RX8010_HOUR - RX8010_SEC] = bin2bcd(tm->tm_hour);
271	date[RX8010_MDAY - RX8010_SEC] = bin2bcd(tm->tm_mday);
272	date[RX8010_MONTH - RX8010_SEC] = bin2bcd(tm->tm_mon);
273	date[RX8010_YEAR - RX8010_SEC] = bin2bcd(tm->tm_year - 2000);
274	date[RX8010_WDAY - RX8010_SEC] = bin2bcd(tm->tm_wday);
275
276	for (int i = 0; i < 7; i++) {
277		ret = rx8010sj_rtc_write8(dev, RX8010_SEC + i, date[i]);
278		if (ret < 0) {
279			DEBUGR("Error writing to RTC. err: %d\n", ret);
280			return -EIO;
281		}
282	}
283
284	/* clear STOP bit after changing clock/calendar */
285	ctrl = rx8010sj_rtc_read8(dev, RX8010_CTRL);
286	if (ctrl < 0)
287		return ctrl;
288
289	ret = rx8010sj_rtc_write8(dev, RX8010_CTRL, ctrl & ~RX8010_CTRL_STOP);
290	if (ret < 0)
291		return ret;
292
293	flagreg = rx8010sj_rtc_read8(dev, RX8010_FLAG);
294	if (flagreg < 0)
295		return flagreg;
296
297	if (flagreg & RX8010_FLAG_VLF)
298		ret = rx8010sj_rtc_write8(dev, RX8010_FLAG,
299					  flagreg & ~RX8010_FLAG_VLF);
300
301	return 0;
302}
303
304/* Reset the RTC. */
305static int rx8010sj_rtc_reset(DEV_TYPE *dev)
306{
307	/* Not needed */
308	return 0;
309}
310
311#ifndef CONFIG_DM_RTC
312
313int rtc_get(struct rtc_time *tm)
314{
315	struct ludevice dev = {
316			.chip = CFG_SYS_I2C_RTC_ADDR,
317	};
318
319	return rx8010sj_rtc_get(&dev, tm);
320}
321
322int rtc_set(struct rtc_time *tm)
323{
324	struct ludevice dev = {
325			.chip = CFG_SYS_I2C_RTC_ADDR,
326	};
327
328	return rx8010sj_rtc_set(&dev, tm);
329}
330
331void rtc_reset(void)
332{
333	struct ludevice dev = {
334			.chip = CFG_SYS_I2C_RTC_ADDR,
335	};
336
337	rx8010sj_rtc_reset(&dev);
338}
339
340void rtc_init(void)
341{
342	struct ludevice dev = {
343			.chip = CFG_SYS_I2C_RTC_ADDR,
344	};
345
346	rx8010sj_rtc_init(&dev);
347}
348
349#else
350
351static int rx8010sj_probe(struct udevice *dev)
352{
353	rx8010sj_rtc_init(dev);
354
355	return 0;
356}
357
358static const struct rtc_ops rx8010sj_rtc_ops = {
359	.get = rx8010sj_rtc_get,
360	.set = rx8010sj_rtc_set,
361	.read8 = rx8010sj_rtc_read8,
362	.write8 = rx8010sj_rtc_write8,
363	.reset = rx8010sj_rtc_reset,
364};
365
366static const struct udevice_id rx8010sj_rtc_ids[] = {
367	{ .compatible = "epson,rx8010sj-rtc" },
368	{ .compatible = "epson,rx8010" },
369	{ }
370};
371
372U_BOOT_DRIVER(rx8010sj_rtc) = {
373	.name	  = "rx8010sj_rtc",
374	.id	      = UCLASS_RTC,
375	.probe    = rx8010sj_probe,
376	.of_match = rx8010sj_rtc_ids,
377	.ops	  = &rx8010sj_rtc_ops,
378};
379
380#endif
381