]>
Commit | Line | Data |
---|---|---|
c46288b0 BB |
1 | /* |
2 | * Seiko Instruments S-35390A RTC Driver | |
3 | * | |
4 | * Copyright (c) 2007 Byron Bradley | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | */ | |
11 | ||
12 | #include <linux/module.h> | |
13 | #include <linux/rtc.h> | |
14 | #include <linux/i2c.h> | |
15 | #include <linux/bitrev.h> | |
16 | #include <linux/bcd.h> | |
17 | #include <linux/slab.h> | |
18 | ||
19 | #define S35390A_CMD_STATUS1 0 | |
20 | #define S35390A_CMD_STATUS2 1 | |
21 | #define S35390A_CMD_TIME1 2 | |
22 | ||
23 | #define S35390A_BYTE_YEAR 0 | |
24 | #define S35390A_BYTE_MONTH 1 | |
25 | #define S35390A_BYTE_DAY 2 | |
26 | #define S35390A_BYTE_WDAY 3 | |
27 | #define S35390A_BYTE_HOURS 4 | |
28 | #define S35390A_BYTE_MINS 5 | |
29 | #define S35390A_BYTE_SECS 6 | |
30 | ||
31 | #define S35390A_FLAG_POC 0x01 | |
32 | #define S35390A_FLAG_BLD 0x02 | |
33 | #define S35390A_FLAG_24H 0x40 | |
34 | #define S35390A_FLAG_RESET 0x80 | |
35 | #define S35390A_FLAG_TEST 0x01 | |
36 | ||
3760f736 JD |
37 | static const struct i2c_device_id s35390a_id[] = { |
38 | { "s35390a", 0 }, | |
39 | { } | |
40 | }; | |
41 | MODULE_DEVICE_TABLE(i2c, s35390a_id); | |
42 | ||
c46288b0 BB |
43 | struct s35390a { |
44 | struct i2c_client *client[8]; | |
45 | struct rtc_device *rtc; | |
46 | int twentyfourhour; | |
47 | }; | |
48 | ||
49 | static int s35390a_set_reg(struct s35390a *s35390a, int reg, char *buf, int len) | |
50 | { | |
51 | struct i2c_client *client = s35390a->client[reg]; | |
52 | struct i2c_msg msg[] = { | |
65659f63 S |
53 | { |
54 | .addr = client->addr, | |
55 | .len = len, | |
56 | .buf = buf | |
57 | }, | |
c46288b0 BB |
58 | }; |
59 | ||
60 | if ((i2c_transfer(client->adapter, msg, 1)) != 1) | |
61 | return -EIO; | |
62 | ||
63 | return 0; | |
64 | } | |
65 | ||
66 | static int s35390a_get_reg(struct s35390a *s35390a, int reg, char *buf, int len) | |
67 | { | |
68 | struct i2c_client *client = s35390a->client[reg]; | |
69 | struct i2c_msg msg[] = { | |
65659f63 S |
70 | { |
71 | .addr = client->addr, | |
72 | .flags = I2C_M_RD, | |
73 | .len = len, | |
74 | .buf = buf | |
75 | }, | |
c46288b0 BB |
76 | }; |
77 | ||
78 | if ((i2c_transfer(client->adapter, msg, 1)) != 1) | |
79 | return -EIO; | |
80 | ||
81 | return 0; | |
82 | } | |
83 | ||
84 | static int s35390a_reset(struct s35390a *s35390a) | |
85 | { | |
86 | char buf[1]; | |
87 | ||
88 | if (s35390a_get_reg(s35390a, S35390A_CMD_STATUS1, buf, sizeof(buf)) < 0) | |
89 | return -EIO; | |
90 | ||
91 | if (!(buf[0] & (S35390A_FLAG_POC | S35390A_FLAG_BLD))) | |
92 | return 0; | |
93 | ||
94 | buf[0] |= (S35390A_FLAG_RESET | S35390A_FLAG_24H); | |
95 | buf[0] &= 0xf0; | |
96 | return s35390a_set_reg(s35390a, S35390A_CMD_STATUS1, buf, sizeof(buf)); | |
97 | } | |
98 | ||
99 | static int s35390a_disable_test_mode(struct s35390a *s35390a) | |
100 | { | |
101 | char buf[1]; | |
102 | ||
103 | if (s35390a_get_reg(s35390a, S35390A_CMD_STATUS2, buf, sizeof(buf)) < 0) | |
104 | return -EIO; | |
105 | ||
106 | if (!(buf[0] & S35390A_FLAG_TEST)) | |
107 | return 0; | |
108 | ||
109 | buf[0] &= ~S35390A_FLAG_TEST; | |
110 | return s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, buf, sizeof(buf)); | |
111 | } | |
112 | ||
113 | static char s35390a_hr2reg(struct s35390a *s35390a, int hour) | |
114 | { | |
115 | if (s35390a->twentyfourhour) | |
fe20ba70 | 116 | return bin2bcd(hour); |
c46288b0 BB |
117 | |
118 | if (hour < 12) | |
fe20ba70 | 119 | return bin2bcd(hour); |
c46288b0 | 120 | |
fe20ba70 | 121 | return 0x40 | bin2bcd(hour - 12); |
c46288b0 BB |
122 | } |
123 | ||
124 | static int s35390a_reg2hr(struct s35390a *s35390a, char reg) | |
125 | { | |
126 | unsigned hour; | |
127 | ||
128 | if (s35390a->twentyfourhour) | |
fe20ba70 | 129 | return bcd2bin(reg & 0x3f); |
c46288b0 | 130 | |
fe20ba70 | 131 | hour = bcd2bin(reg & 0x3f); |
c46288b0 BB |
132 | if (reg & 0x40) |
133 | hour += 12; | |
134 | ||
135 | return hour; | |
136 | } | |
137 | ||
138 | static int s35390a_set_datetime(struct i2c_client *client, struct rtc_time *tm) | |
139 | { | |
140 | struct s35390a *s35390a = i2c_get_clientdata(client); | |
141 | int i, err; | |
142 | char buf[7]; | |
143 | ||
144 | dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d mday=%d, " | |
145 | "mon=%d, year=%d, wday=%d\n", __func__, tm->tm_sec, | |
146 | tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon, tm->tm_year, | |
147 | tm->tm_wday); | |
148 | ||
fe20ba70 AB |
149 | buf[S35390A_BYTE_YEAR] = bin2bcd(tm->tm_year - 100); |
150 | buf[S35390A_BYTE_MONTH] = bin2bcd(tm->tm_mon + 1); | |
151 | buf[S35390A_BYTE_DAY] = bin2bcd(tm->tm_mday); | |
152 | buf[S35390A_BYTE_WDAY] = bin2bcd(tm->tm_wday); | |
c46288b0 | 153 | buf[S35390A_BYTE_HOURS] = s35390a_hr2reg(s35390a, tm->tm_hour); |
fe20ba70 AB |
154 | buf[S35390A_BYTE_MINS] = bin2bcd(tm->tm_min); |
155 | buf[S35390A_BYTE_SECS] = bin2bcd(tm->tm_sec); | |
c46288b0 BB |
156 | |
157 | /* This chip expects the bits of each byte to be in reverse order */ | |
158 | for (i = 0; i < 7; ++i) | |
159 | buf[i] = bitrev8(buf[i]); | |
160 | ||
161 | err = s35390a_set_reg(s35390a, S35390A_CMD_TIME1, buf, sizeof(buf)); | |
162 | ||
163 | return err; | |
164 | } | |
165 | ||
166 | static int s35390a_get_datetime(struct i2c_client *client, struct rtc_time *tm) | |
167 | { | |
168 | struct s35390a *s35390a = i2c_get_clientdata(client); | |
169 | char buf[7]; | |
170 | int i, err; | |
171 | ||
172 | err = s35390a_get_reg(s35390a, S35390A_CMD_TIME1, buf, sizeof(buf)); | |
173 | if (err < 0) | |
174 | return err; | |
175 | ||
176 | /* This chip returns the bits of each byte in reverse order */ | |
177 | for (i = 0; i < 7; ++i) | |
178 | buf[i] = bitrev8(buf[i]); | |
179 | ||
fe20ba70 AB |
180 | tm->tm_sec = bcd2bin(buf[S35390A_BYTE_SECS]); |
181 | tm->tm_min = bcd2bin(buf[S35390A_BYTE_MINS]); | |
c46288b0 | 182 | tm->tm_hour = s35390a_reg2hr(s35390a, buf[S35390A_BYTE_HOURS]); |
fe20ba70 AB |
183 | tm->tm_wday = bcd2bin(buf[S35390A_BYTE_WDAY]); |
184 | tm->tm_mday = bcd2bin(buf[S35390A_BYTE_DAY]); | |
185 | tm->tm_mon = bcd2bin(buf[S35390A_BYTE_MONTH]) - 1; | |
186 | tm->tm_year = bcd2bin(buf[S35390A_BYTE_YEAR]) + 100; | |
c46288b0 BB |
187 | |
188 | dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, mday=%d, " | |
189 | "mon=%d, year=%d, wday=%d\n", __func__, tm->tm_sec, | |
190 | tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon, tm->tm_year, | |
191 | tm->tm_wday); | |
192 | ||
193 | return rtc_valid_tm(tm); | |
194 | } | |
195 | ||
196 | static int s35390a_rtc_read_time(struct device *dev, struct rtc_time *tm) | |
197 | { | |
198 | return s35390a_get_datetime(to_i2c_client(dev), tm); | |
199 | } | |
200 | ||
201 | static int s35390a_rtc_set_time(struct device *dev, struct rtc_time *tm) | |
202 | { | |
203 | return s35390a_set_datetime(to_i2c_client(dev), tm); | |
204 | } | |
205 | ||
206 | static const struct rtc_class_ops s35390a_rtc_ops = { | |
207 | .read_time = s35390a_rtc_read_time, | |
208 | .set_time = s35390a_rtc_set_time, | |
209 | }; | |
210 | ||
211 | static struct i2c_driver s35390a_driver; | |
212 | ||
d2653e92 JD |
213 | static int s35390a_probe(struct i2c_client *client, |
214 | const struct i2c_device_id *id) | |
c46288b0 BB |
215 | { |
216 | int err; | |
217 | unsigned int i; | |
218 | struct s35390a *s35390a; | |
219 | struct rtc_time tm; | |
220 | char buf[1]; | |
221 | ||
222 | if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { | |
223 | err = -ENODEV; | |
224 | goto exit; | |
225 | } | |
226 | ||
227 | s35390a = kzalloc(sizeof(struct s35390a), GFP_KERNEL); | |
228 | if (!s35390a) { | |
229 | err = -ENOMEM; | |
230 | goto exit; | |
231 | } | |
232 | ||
233 | s35390a->client[0] = client; | |
234 | i2c_set_clientdata(client, s35390a); | |
235 | ||
236 | /* This chip uses multiple addresses, use dummy devices for them */ | |
237 | for (i = 1; i < 8; ++i) { | |
238 | s35390a->client[i] = i2c_new_dummy(client->adapter, | |
60b129d7 | 239 | client->addr + i); |
c46288b0 BB |
240 | if (!s35390a->client[i]) { |
241 | dev_err(&client->dev, "Address %02x unavailable\n", | |
242 | client->addr + i); | |
243 | err = -EBUSY; | |
244 | goto exit_dummy; | |
245 | } | |
246 | } | |
247 | ||
248 | err = s35390a_reset(s35390a); | |
249 | if (err < 0) { | |
250 | dev_err(&client->dev, "error resetting chip\n"); | |
251 | goto exit_dummy; | |
252 | } | |
253 | ||
254 | err = s35390a_disable_test_mode(s35390a); | |
255 | if (err < 0) { | |
256 | dev_err(&client->dev, "error disabling test mode\n"); | |
257 | goto exit_dummy; | |
258 | } | |
259 | ||
260 | err = s35390a_get_reg(s35390a, S35390A_CMD_STATUS1, buf, sizeof(buf)); | |
261 | if (err < 0) { | |
262 | dev_err(&client->dev, "error checking 12/24 hour mode\n"); | |
263 | goto exit_dummy; | |
264 | } | |
265 | if (buf[0] & S35390A_FLAG_24H) | |
266 | s35390a->twentyfourhour = 1; | |
267 | else | |
268 | s35390a->twentyfourhour = 0; | |
269 | ||
270 | if (s35390a_get_datetime(client, &tm) < 0) | |
271 | dev_warn(&client->dev, "clock needs to be set\n"); | |
272 | ||
273 | s35390a->rtc = rtc_device_register(s35390a_driver.driver.name, | |
274 | &client->dev, &s35390a_rtc_ops, THIS_MODULE); | |
275 | ||
276 | if (IS_ERR(s35390a->rtc)) { | |
277 | err = PTR_ERR(s35390a->rtc); | |
278 | goto exit_dummy; | |
279 | } | |
280 | return 0; | |
281 | ||
282 | exit_dummy: | |
283 | for (i = 1; i < 8; ++i) | |
284 | if (s35390a->client[i]) | |
285 | i2c_unregister_device(s35390a->client[i]); | |
286 | kfree(s35390a); | |
c46288b0 BB |
287 | |
288 | exit: | |
289 | return err; | |
290 | } | |
291 | ||
292 | static int s35390a_remove(struct i2c_client *client) | |
293 | { | |
294 | unsigned int i; | |
295 | ||
296 | struct s35390a *s35390a = i2c_get_clientdata(client); | |
297 | for (i = 1; i < 8; ++i) | |
298 | if (s35390a->client[i]) | |
299 | i2c_unregister_device(s35390a->client[i]); | |
300 | ||
301 | rtc_device_unregister(s35390a->rtc); | |
302 | kfree(s35390a); | |
c46288b0 BB |
303 | |
304 | return 0; | |
305 | } | |
306 | ||
307 | static struct i2c_driver s35390a_driver = { | |
308 | .driver = { | |
309 | .name = "rtc-s35390a", | |
310 | }, | |
311 | .probe = s35390a_probe, | |
312 | .remove = s35390a_remove, | |
3760f736 | 313 | .id_table = s35390a_id, |
c46288b0 BB |
314 | }; |
315 | ||
0abc9201 | 316 | module_i2c_driver(s35390a_driver); |
c46288b0 BB |
317 | |
318 | MODULE_AUTHOR("Byron Bradley <byron.bbradley@gmail.com>"); | |
319 | MODULE_DESCRIPTION("S35390A RTC driver"); | |
320 | MODULE_LICENSE("GPL"); |