Commit | Line | Data |
---|---|---|
b5a82d62 AZ |
1 | /* |
2 | * An I2C driver for the Philips PCF8563 RTC | |
3 | * Copyright 2005-06 Tower Technologies | |
4 | * | |
5 | * Author: Alessandro Zummo <a.zummo@towertech.it> | |
6 | * Maintainers: http://www.nslu2-linux.org/ | |
7 | * | |
8 | * based on the other drivers in this same directory. | |
9 | * | |
10 | * http://www.semiconductors.philips.com/acrobat/datasheets/PCF8563-04.pdf | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License version 2 as | |
14 | * published by the Free Software Foundation. | |
15 | */ | |
16 | ||
17 | #include <linux/i2c.h> | |
18 | #include <linux/bcd.h> | |
19 | #include <linux/rtc.h> | |
5a0e3ad6 | 20 | #include <linux/slab.h> |
2113852b | 21 | #include <linux/module.h> |
b5a82d62 | 22 | |
e5fc9cc0 | 23 | #define DRV_VERSION "0.4.3" |
b5a82d62 AZ |
24 | |
25 | #define PCF8563_REG_ST1 0x00 /* status */ | |
26 | #define PCF8563_REG_ST2 0x01 | |
27 | ||
28 | #define PCF8563_REG_SC 0x02 /* datetime */ | |
29 | #define PCF8563_REG_MN 0x03 | |
30 | #define PCF8563_REG_HR 0x04 | |
31 | #define PCF8563_REG_DM 0x05 | |
32 | #define PCF8563_REG_DW 0x06 | |
33 | #define PCF8563_REG_MO 0x07 | |
34 | #define PCF8563_REG_YR 0x08 | |
35 | ||
36 | #define PCF8563_REG_AMN 0x09 /* alarm */ | |
37 | #define PCF8563_REG_AHR 0x0A | |
38 | #define PCF8563_REG_ADM 0x0B | |
39 | #define PCF8563_REG_ADW 0x0C | |
40 | ||
41 | #define PCF8563_REG_CLKO 0x0D /* clock out */ | |
42 | #define PCF8563_REG_TMRC 0x0E /* timer control */ | |
43 | #define PCF8563_REG_TMR 0x0F /* timer */ | |
44 | ||
45 | #define PCF8563_SC_LV 0x80 /* low voltage */ | |
46 | #define PCF8563_MO_C 0x80 /* century */ | |
47 | ||
e5fc9cc0 AZ |
48 | static struct i2c_driver pcf8563_driver; |
49 | ||
cbb94502 | 50 | struct pcf8563 { |
e5fc9cc0 | 51 | struct rtc_device *rtc; |
cbb94502 AN |
52 | /* |
53 | * The meaning of MO_C bit varies by the chip type. | |
54 | * From PCF8563 datasheet: this bit is toggled when the years | |
55 | * register overflows from 99 to 00 | |
56 | * 0 indicates the century is 20xx | |
57 | * 1 indicates the century is 19xx | |
58 | * From RTC8564 datasheet: this bit indicates change of | |
59 | * century. When the year digit data overflows from 99 to 00, | |
60 | * this bit is set. By presetting it to 0 while still in the | |
61 | * 20th century, it will be set in year 2000, ... | |
62 | * There seems no reliable way to know how the system use this | |
63 | * bit. So let's do it heuristically, assuming we are live in | |
64 | * 1970...2069. | |
65 | */ | |
66 | int c_polarity; /* 0: MO_C=1 means 19xx, otherwise MO_C=1 means 20xx */ | |
0f20b767 | 67 | int voltage_low; /* incicates if a low_voltage was detected */ |
cbb94502 AN |
68 | }; |
69 | ||
b5a82d62 AZ |
70 | /* |
71 | * In the routines that deal directly with the pcf8563 hardware, we use | |
72 | * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch. | |
73 | */ | |
74 | static int pcf8563_get_datetime(struct i2c_client *client, struct rtc_time *tm) | |
75 | { | |
e5fc9cc0 | 76 | struct pcf8563 *pcf8563 = i2c_get_clientdata(client); |
b5a82d62 AZ |
77 | unsigned char buf[13] = { PCF8563_REG_ST1 }; |
78 | ||
79 | struct i2c_msg msgs[] = { | |
80 | { client->addr, 0, 1, buf }, /* setup read ptr */ | |
81 | { client->addr, I2C_M_RD, 13, buf }, /* read status + date */ | |
82 | }; | |
83 | ||
84 | /* read registers */ | |
85 | if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { | |
2a4e2b87 | 86 | dev_err(&client->dev, "%s: read error\n", __func__); |
b5a82d62 AZ |
87 | return -EIO; |
88 | } | |
89 | ||
0f20b767 AS |
90 | if (buf[PCF8563_REG_SC] & PCF8563_SC_LV) { |
91 | pcf8563->voltage_low = 1; | |
b5a82d62 AZ |
92 | dev_info(&client->dev, |
93 | "low voltage detected, date/time is not reliable.\n"); | |
0f20b767 | 94 | } |
b5a82d62 AZ |
95 | |
96 | dev_dbg(&client->dev, | |
97 | "%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, " | |
98 | "mday=%02x, wday=%02x, mon=%02x, year=%02x\n", | |
2a4e2b87 | 99 | __func__, |
b5a82d62 AZ |
100 | buf[0], buf[1], buf[2], buf[3], |
101 | buf[4], buf[5], buf[6], buf[7], | |
102 | buf[8]); | |
103 | ||
104 | ||
fe20ba70 AB |
105 | tm->tm_sec = bcd2bin(buf[PCF8563_REG_SC] & 0x7F); |
106 | tm->tm_min = bcd2bin(buf[PCF8563_REG_MN] & 0x7F); | |
107 | tm->tm_hour = bcd2bin(buf[PCF8563_REG_HR] & 0x3F); /* rtc hr 0-23 */ | |
108 | tm->tm_mday = bcd2bin(buf[PCF8563_REG_DM] & 0x3F); | |
b5a82d62 | 109 | tm->tm_wday = buf[PCF8563_REG_DW] & 0x07; |
fe20ba70 AB |
110 | tm->tm_mon = bcd2bin(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */ |
111 | tm->tm_year = bcd2bin(buf[PCF8563_REG_YR]); | |
cbb94502 AN |
112 | if (tm->tm_year < 70) |
113 | tm->tm_year += 100; /* assume we are in 1970...2069 */ | |
114 | /* detect the polarity heuristically. see note above. */ | |
115 | pcf8563->c_polarity = (buf[PCF8563_REG_MO] & PCF8563_MO_C) ? | |
116 | (tm->tm_year >= 100) : (tm->tm_year < 100); | |
b5a82d62 AZ |
117 | |
118 | dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, " | |
119 | "mday=%d, mon=%d, year=%d, wday=%d\n", | |
2a4e2b87 | 120 | __func__, |
b5a82d62 AZ |
121 | tm->tm_sec, tm->tm_min, tm->tm_hour, |
122 | tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); | |
123 | ||
124 | /* the clock can give out invalid datetime, but we cannot return | |
125 | * -EINVAL otherwise hwclock will refuse to set the time on bootup. | |
126 | */ | |
127 | if (rtc_valid_tm(tm) < 0) | |
128 | dev_err(&client->dev, "retrieved date/time is not valid.\n"); | |
129 | ||
130 | return 0; | |
131 | } | |
132 | ||
133 | static int pcf8563_set_datetime(struct i2c_client *client, struct rtc_time *tm) | |
134 | { | |
e5fc9cc0 | 135 | struct pcf8563 *pcf8563 = i2c_get_clientdata(client); |
b5a82d62 AZ |
136 | int i, err; |
137 | unsigned char buf[9]; | |
138 | ||
139 | dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, " | |
140 | "mday=%d, mon=%d, year=%d, wday=%d\n", | |
2a4e2b87 | 141 | __func__, |
b5a82d62 AZ |
142 | tm->tm_sec, tm->tm_min, tm->tm_hour, |
143 | tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); | |
144 | ||
145 | /* hours, minutes and seconds */ | |
fe20ba70 AB |
146 | buf[PCF8563_REG_SC] = bin2bcd(tm->tm_sec); |
147 | buf[PCF8563_REG_MN] = bin2bcd(tm->tm_min); | |
148 | buf[PCF8563_REG_HR] = bin2bcd(tm->tm_hour); | |
b5a82d62 | 149 | |
fe20ba70 | 150 | buf[PCF8563_REG_DM] = bin2bcd(tm->tm_mday); |
b5a82d62 AZ |
151 | |
152 | /* month, 1 - 12 */ | |
fe20ba70 | 153 | buf[PCF8563_REG_MO] = bin2bcd(tm->tm_mon + 1); |
b5a82d62 AZ |
154 | |
155 | /* year and century */ | |
fe20ba70 | 156 | buf[PCF8563_REG_YR] = bin2bcd(tm->tm_year % 100); |
cbb94502 | 157 | if (pcf8563->c_polarity ? (tm->tm_year >= 100) : (tm->tm_year < 100)) |
b5a82d62 AZ |
158 | buf[PCF8563_REG_MO] |= PCF8563_MO_C; |
159 | ||
160 | buf[PCF8563_REG_DW] = tm->tm_wday & 0x07; | |
161 | ||
162 | /* write register's data */ | |
163 | for (i = 0; i < 7; i++) { | |
164 | unsigned char data[2] = { PCF8563_REG_SC + i, | |
165 | buf[PCF8563_REG_SC + i] }; | |
166 | ||
167 | err = i2c_master_send(client, data, sizeof(data)); | |
168 | if (err != sizeof(data)) { | |
169 | dev_err(&client->dev, | |
170 | "%s: err=%d addr=%02x, data=%02x\n", | |
2a4e2b87 | 171 | __func__, err, data[0], data[1]); |
b5a82d62 AZ |
172 | return -EIO; |
173 | } | |
174 | }; | |
175 | ||
176 | return 0; | |
177 | } | |
178 | ||
0f20b767 AS |
179 | #ifdef CONFIG_RTC_INTF_DEV |
180 | static int pcf8563_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) | |
181 | { | |
182 | struct pcf8563 *pcf8563 = i2c_get_clientdata(to_i2c_client(dev)); | |
183 | struct rtc_time tm; | |
184 | ||
185 | switch (cmd) { | |
186 | case RTC_VL_READ: | |
187 | if (pcf8563->voltage_low) | |
188 | dev_info(dev, "low voltage detected, date/time is not reliable.\n"); | |
189 | ||
190 | if (copy_to_user((void __user *)arg, &pcf8563->voltage_low, | |
191 | sizeof(int))) | |
192 | return -EFAULT; | |
193 | return 0; | |
194 | case RTC_VL_CLR: | |
195 | /* | |
196 | * Clear the VL bit in the seconds register in case | |
197 | * the time has not been set already (which would | |
198 | * have cleared it). This does not really matter | |
199 | * because of the cached voltage_low value but do it | |
200 | * anyway for consistency. | |
201 | */ | |
202 | if (pcf8563_get_datetime(to_i2c_client(dev), &tm)) | |
203 | pcf8563_set_datetime(to_i2c_client(dev), &tm); | |
204 | ||
205 | /* Clear the cached value. */ | |
206 | pcf8563->voltage_low = 0; | |
207 | ||
208 | return 0; | |
209 | default: | |
210 | return -ENOIOCTLCMD; | |
211 | } | |
212 | } | |
213 | #else | |
214 | #define pcf8563_rtc_ioctl NULL | |
215 | #endif | |
216 | ||
b5a82d62 AZ |
217 | static int pcf8563_rtc_read_time(struct device *dev, struct rtc_time *tm) |
218 | { | |
219 | return pcf8563_get_datetime(to_i2c_client(dev), tm); | |
220 | } | |
221 | ||
222 | static int pcf8563_rtc_set_time(struct device *dev, struct rtc_time *tm) | |
223 | { | |
224 | return pcf8563_set_datetime(to_i2c_client(dev), tm); | |
225 | } | |
226 | ||
ff8371ac | 227 | static const struct rtc_class_ops pcf8563_rtc_ops = { |
0f20b767 | 228 | .ioctl = pcf8563_rtc_ioctl, |
b5a82d62 AZ |
229 | .read_time = pcf8563_rtc_read_time, |
230 | .set_time = pcf8563_rtc_set_time, | |
231 | }; | |
232 | ||
d2653e92 JD |
233 | static int pcf8563_probe(struct i2c_client *client, |
234 | const struct i2c_device_id *id) | |
b5a82d62 | 235 | { |
cbb94502 | 236 | struct pcf8563 *pcf8563; |
b5a82d62 AZ |
237 | |
238 | int err = 0; | |
239 | ||
e5fc9cc0 | 240 | dev_dbg(&client->dev, "%s\n", __func__); |
b5a82d62 | 241 | |
e5fc9cc0 AZ |
242 | if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) |
243 | return -ENODEV; | |
b5a82d62 | 244 | |
e5fc9cc0 AZ |
245 | pcf8563 = kzalloc(sizeof(struct pcf8563), GFP_KERNEL); |
246 | if (!pcf8563) | |
247 | return -ENOMEM; | |
b5a82d62 | 248 | |
b5a82d62 AZ |
249 | dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); |
250 | ||
b74d2caa AZ |
251 | i2c_set_clientdata(client, pcf8563); |
252 | ||
e5fc9cc0 AZ |
253 | pcf8563->rtc = rtc_device_register(pcf8563_driver.driver.name, |
254 | &client->dev, &pcf8563_rtc_ops, THIS_MODULE); | |
b5a82d62 | 255 | |
e5fc9cc0 AZ |
256 | if (IS_ERR(pcf8563->rtc)) { |
257 | err = PTR_ERR(pcf8563->rtc); | |
258 | goto exit_kfree; | |
b5a82d62 AZ |
259 | } |
260 | ||
b5a82d62 AZ |
261 | return 0; |
262 | ||
b5a82d62 | 263 | exit_kfree: |
cbb94502 | 264 | kfree(pcf8563); |
b5a82d62 | 265 | |
b5a82d62 AZ |
266 | return err; |
267 | } | |
268 | ||
e5fc9cc0 | 269 | static int pcf8563_remove(struct i2c_client *client) |
b5a82d62 | 270 | { |
e5fc9cc0 | 271 | struct pcf8563 *pcf8563 = i2c_get_clientdata(client); |
b5a82d62 | 272 | |
e5fc9cc0 AZ |
273 | if (pcf8563->rtc) |
274 | rtc_device_unregister(pcf8563->rtc); | |
b5a82d62 | 275 | |
cbb94502 | 276 | kfree(pcf8563); |
b5a82d62 AZ |
277 | |
278 | return 0; | |
279 | } | |
280 | ||
3760f736 JD |
281 | static const struct i2c_device_id pcf8563_id[] = { |
282 | { "pcf8563", 0 }, | |
8ea9212c | 283 | { "rtc8564", 0 }, |
3760f736 JD |
284 | { } |
285 | }; | |
286 | MODULE_DEVICE_TABLE(i2c, pcf8563_id); | |
287 | ||
e5fc9cc0 AZ |
288 | static struct i2c_driver pcf8563_driver = { |
289 | .driver = { | |
290 | .name = "rtc-pcf8563", | |
291 | }, | |
292 | .probe = pcf8563_probe, | |
293 | .remove = pcf8563_remove, | |
3760f736 | 294 | .id_table = pcf8563_id, |
e5fc9cc0 AZ |
295 | }; |
296 | ||
0abc9201 | 297 | module_i2c_driver(pcf8563_driver); |
b5a82d62 AZ |
298 | |
299 | MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); | |
300 | MODULE_DESCRIPTION("Philips PCF8563/Epson RTC8564 RTC driver"); | |
301 | MODULE_LICENSE("GPL"); | |
302 | MODULE_VERSION(DRV_VERSION); |