Commit | Line | Data |
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caaff562 AN |
1 | /* |
2 | * I2C client/driver for the ST M41T80 family of i2c rtc chips. | |
3 | * | |
4 | * Author: Alexander Bigga <ab@mycable.de> | |
5 | * | |
6 | * Based on m41t00.c by Mark A. Greer <mgreer@mvista.com> | |
7 | * | |
8 | * 2006 (c) mycable GmbH | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or modify | |
11 | * it under the terms of the GNU General Public License version 2 as | |
12 | * published by the Free Software Foundation. | |
13 | * | |
14 | */ | |
15 | ||
35aa64f3 MR |
16 | #include <linux/bcd.h> |
17 | #include <linux/i2c.h> | |
caaff562 | 18 | #include <linux/init.h> |
9fb1f68d | 19 | #include <linux/kernel.h> |
35aa64f3 MR |
20 | #include <linux/module.h> |
21 | #include <linux/rtc.h> | |
caaff562 | 22 | #include <linux/slab.h> |
41012735 | 23 | #include <linux/smp_lock.h> |
caaff562 | 24 | #include <linux/string.h> |
617780d2 | 25 | #ifdef CONFIG_RTC_DRV_M41T80_WDT |
617780d2 AN |
26 | #include <linux/fs.h> |
27 | #include <linux/ioctl.h> | |
35aa64f3 MR |
28 | #include <linux/miscdevice.h> |
29 | #include <linux/reboot.h> | |
30 | #include <linux/watchdog.h> | |
617780d2 | 31 | #endif |
caaff562 AN |
32 | |
33 | #define M41T80_REG_SSEC 0 | |
34 | #define M41T80_REG_SEC 1 | |
35 | #define M41T80_REG_MIN 2 | |
36 | #define M41T80_REG_HOUR 3 | |
37 | #define M41T80_REG_WDAY 4 | |
38 | #define M41T80_REG_DAY 5 | |
39 | #define M41T80_REG_MON 6 | |
40 | #define M41T80_REG_YEAR 7 | |
41 | #define M41T80_REG_ALARM_MON 0xa | |
42 | #define M41T80_REG_ALARM_DAY 0xb | |
43 | #define M41T80_REG_ALARM_HOUR 0xc | |
44 | #define M41T80_REG_ALARM_MIN 0xd | |
45 | #define M41T80_REG_ALARM_SEC 0xe | |
46 | #define M41T80_REG_FLAGS 0xf | |
47 | #define M41T80_REG_SQW 0x13 | |
48 | ||
49 | #define M41T80_DATETIME_REG_SIZE (M41T80_REG_YEAR + 1) | |
50 | #define M41T80_ALARM_REG_SIZE \ | |
51 | (M41T80_REG_ALARM_SEC + 1 - M41T80_REG_ALARM_MON) | |
52 | ||
53 | #define M41T80_SEC_ST (1 << 7) /* ST: Stop Bit */ | |
54 | #define M41T80_ALMON_AFE (1 << 7) /* AFE: AF Enable Bit */ | |
55 | #define M41T80_ALMON_SQWE (1 << 6) /* SQWE: SQW Enable Bit */ | |
56 | #define M41T80_ALHOUR_HT (1 << 6) /* HT: Halt Update Bit */ | |
57 | #define M41T80_FLAGS_AF (1 << 6) /* AF: Alarm Flag Bit */ | |
58 | #define M41T80_FLAGS_BATT_LOW (1 << 4) /* BL: Battery Low Bit */ | |
d3a126fc SF |
59 | #define M41T80_WATCHDOG_RB2 (1 << 7) /* RB: Watchdog resolution */ |
60 | #define M41T80_WATCHDOG_RB1 (1 << 1) /* RB: Watchdog resolution */ | |
61 | #define M41T80_WATCHDOG_RB0 (1 << 0) /* RB: Watchdog resolution */ | |
caaff562 | 62 | |
d3a126fc SF |
63 | #define M41T80_FEATURE_HT (1 << 0) /* Halt feature */ |
64 | #define M41T80_FEATURE_BL (1 << 1) /* Battery low indicator */ | |
65 | #define M41T80_FEATURE_SQ (1 << 2) /* Squarewave feature */ | |
66 | #define M41T80_FEATURE_WD (1 << 3) /* Extra watchdog resolution */ | |
f30281f4 | 67 | #define M41T80_FEATURE_SQ_ALT (1 << 4) /* RSx bits are in reg 4 */ |
caaff562 AN |
68 | |
69 | #define DRV_VERSION "0.05" | |
70 | ||
3760f736 | 71 | static const struct i2c_device_id m41t80_id[] = { |
f30281f4 | 72 | { "m41t62", M41T80_FEATURE_SQ | M41T80_FEATURE_SQ_ALT }, |
d3a126fc SF |
73 | { "m41t65", M41T80_FEATURE_HT | M41T80_FEATURE_WD }, |
74 | { "m41t80", M41T80_FEATURE_SQ }, | |
75 | { "m41t81", M41T80_FEATURE_HT | M41T80_FEATURE_SQ}, | |
76 | { "m41t81s", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ }, | |
77 | { "m41t82", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ }, | |
78 | { "m41t83", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ }, | |
79 | { "m41st84", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ }, | |
80 | { "m41st85", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ }, | |
81 | { "m41st87", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ }, | |
3760f736 | 82 | { } |
caaff562 | 83 | }; |
3760f736 | 84 | MODULE_DEVICE_TABLE(i2c, m41t80_id); |
caaff562 AN |
85 | |
86 | struct m41t80_data { | |
3760f736 | 87 | u8 features; |
caaff562 AN |
88 | struct rtc_device *rtc; |
89 | }; | |
90 | ||
91 | static int m41t80_get_datetime(struct i2c_client *client, | |
92 | struct rtc_time *tm) | |
93 | { | |
94 | u8 buf[M41T80_DATETIME_REG_SIZE], dt_addr[1] = { M41T80_REG_SEC }; | |
95 | struct i2c_msg msgs[] = { | |
96 | { | |
97 | .addr = client->addr, | |
98 | .flags = 0, | |
99 | .len = 1, | |
100 | .buf = dt_addr, | |
101 | }, | |
102 | { | |
103 | .addr = client->addr, | |
104 | .flags = I2C_M_RD, | |
105 | .len = M41T80_DATETIME_REG_SIZE - M41T80_REG_SEC, | |
106 | .buf = buf + M41T80_REG_SEC, | |
107 | }, | |
108 | }; | |
109 | ||
110 | if (i2c_transfer(client->adapter, msgs, 2) < 0) { | |
111 | dev_err(&client->dev, "read error\n"); | |
112 | return -EIO; | |
113 | } | |
114 | ||
fe20ba70 AB |
115 | tm->tm_sec = bcd2bin(buf[M41T80_REG_SEC] & 0x7f); |
116 | tm->tm_min = bcd2bin(buf[M41T80_REG_MIN] & 0x7f); | |
117 | tm->tm_hour = bcd2bin(buf[M41T80_REG_HOUR] & 0x3f); | |
118 | tm->tm_mday = bcd2bin(buf[M41T80_REG_DAY] & 0x3f); | |
caaff562 | 119 | tm->tm_wday = buf[M41T80_REG_WDAY] & 0x07; |
fe20ba70 | 120 | tm->tm_mon = bcd2bin(buf[M41T80_REG_MON] & 0x1f) - 1; |
caaff562 AN |
121 | |
122 | /* assume 20YY not 19YY, and ignore the Century Bit */ | |
fe20ba70 | 123 | tm->tm_year = bcd2bin(buf[M41T80_REG_YEAR]) + 100; |
caaff562 AN |
124 | return 0; |
125 | } | |
126 | ||
127 | /* Sets the given date and time to the real time clock. */ | |
128 | static int m41t80_set_datetime(struct i2c_client *client, struct rtc_time *tm) | |
129 | { | |
130 | u8 wbuf[1 + M41T80_DATETIME_REG_SIZE]; | |
131 | u8 *buf = &wbuf[1]; | |
132 | u8 dt_addr[1] = { M41T80_REG_SEC }; | |
133 | struct i2c_msg msgs_in[] = { | |
134 | { | |
135 | .addr = client->addr, | |
136 | .flags = 0, | |
137 | .len = 1, | |
138 | .buf = dt_addr, | |
139 | }, | |
140 | { | |
141 | .addr = client->addr, | |
142 | .flags = I2C_M_RD, | |
143 | .len = M41T80_DATETIME_REG_SIZE - M41T80_REG_SEC, | |
144 | .buf = buf + M41T80_REG_SEC, | |
145 | }, | |
146 | }; | |
147 | struct i2c_msg msgs[] = { | |
148 | { | |
149 | .addr = client->addr, | |
150 | .flags = 0, | |
151 | .len = 1 + M41T80_DATETIME_REG_SIZE, | |
152 | .buf = wbuf, | |
153 | }, | |
154 | }; | |
155 | ||
156 | /* Read current reg values into buf[1..7] */ | |
157 | if (i2c_transfer(client->adapter, msgs_in, 2) < 0) { | |
158 | dev_err(&client->dev, "read error\n"); | |
159 | return -EIO; | |
160 | } | |
161 | ||
162 | wbuf[0] = 0; /* offset into rtc's regs */ | |
163 | /* Merge time-data and register flags into buf[0..7] */ | |
164 | buf[M41T80_REG_SSEC] = 0; | |
165 | buf[M41T80_REG_SEC] = | |
fe20ba70 | 166 | bin2bcd(tm->tm_sec) | (buf[M41T80_REG_SEC] & ~0x7f); |
caaff562 | 167 | buf[M41T80_REG_MIN] = |
fe20ba70 | 168 | bin2bcd(tm->tm_min) | (buf[M41T80_REG_MIN] & ~0x7f); |
caaff562 | 169 | buf[M41T80_REG_HOUR] = |
fe20ba70 | 170 | bin2bcd(tm->tm_hour) | (buf[M41T80_REG_HOUR] & ~0x3f) ; |
caaff562 AN |
171 | buf[M41T80_REG_WDAY] = |
172 | (tm->tm_wday & 0x07) | (buf[M41T80_REG_WDAY] & ~0x07); | |
173 | buf[M41T80_REG_DAY] = | |
fe20ba70 | 174 | bin2bcd(tm->tm_mday) | (buf[M41T80_REG_DAY] & ~0x3f); |
caaff562 | 175 | buf[M41T80_REG_MON] = |
fe20ba70 | 176 | bin2bcd(tm->tm_mon + 1) | (buf[M41T80_REG_MON] & ~0x1f); |
caaff562 | 177 | /* assume 20YY not 19YY */ |
fe20ba70 | 178 | buf[M41T80_REG_YEAR] = bin2bcd(tm->tm_year % 100); |
caaff562 AN |
179 | |
180 | if (i2c_transfer(client->adapter, msgs, 1) != 1) { | |
181 | dev_err(&client->dev, "write error\n"); | |
182 | return -EIO; | |
183 | } | |
184 | return 0; | |
185 | } | |
186 | ||
187 | #if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE) | |
188 | static int m41t80_rtc_proc(struct device *dev, struct seq_file *seq) | |
189 | { | |
190 | struct i2c_client *client = to_i2c_client(dev); | |
191 | struct m41t80_data *clientdata = i2c_get_clientdata(client); | |
192 | u8 reg; | |
193 | ||
3760f736 | 194 | if (clientdata->features & M41T80_FEATURE_BL) { |
caaff562 AN |
195 | reg = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS); |
196 | seq_printf(seq, "battery\t\t: %s\n", | |
197 | (reg & M41T80_FLAGS_BATT_LOW) ? "exhausted" : "ok"); | |
198 | } | |
199 | return 0; | |
200 | } | |
201 | #else | |
202 | #define m41t80_rtc_proc NULL | |
203 | #endif | |
204 | ||
205 | static int m41t80_rtc_read_time(struct device *dev, struct rtc_time *tm) | |
206 | { | |
207 | return m41t80_get_datetime(to_i2c_client(dev), tm); | |
208 | } | |
209 | ||
210 | static int m41t80_rtc_set_time(struct device *dev, struct rtc_time *tm) | |
211 | { | |
212 | return m41t80_set_datetime(to_i2c_client(dev), tm); | |
213 | } | |
214 | ||
215 | #if defined(CONFIG_RTC_INTF_DEV) || defined(CONFIG_RTC_INTF_DEV_MODULE) | |
216 | static int | |
217 | m41t80_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) | |
218 | { | |
219 | struct i2c_client *client = to_i2c_client(dev); | |
220 | int rc; | |
221 | ||
222 | switch (cmd) { | |
223 | case RTC_AIE_OFF: | |
224 | case RTC_AIE_ON: | |
225 | break; | |
226 | default: | |
227 | return -ENOIOCTLCMD; | |
228 | } | |
229 | ||
230 | rc = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON); | |
231 | if (rc < 0) | |
232 | goto err; | |
233 | switch (cmd) { | |
234 | case RTC_AIE_OFF: | |
235 | rc &= ~M41T80_ALMON_AFE; | |
236 | break; | |
237 | case RTC_AIE_ON: | |
238 | rc |= M41T80_ALMON_AFE; | |
239 | break; | |
240 | } | |
241 | if (i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, rc) < 0) | |
242 | goto err; | |
243 | return 0; | |
244 | err: | |
245 | return -EIO; | |
246 | } | |
247 | #else | |
248 | #define m41t80_rtc_ioctl NULL | |
249 | #endif | |
250 | ||
251 | static int m41t80_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *t) | |
252 | { | |
253 | struct i2c_client *client = to_i2c_client(dev); | |
254 | u8 wbuf[1 + M41T80_ALARM_REG_SIZE]; | |
255 | u8 *buf = &wbuf[1]; | |
256 | u8 *reg = buf - M41T80_REG_ALARM_MON; | |
257 | u8 dt_addr[1] = { M41T80_REG_ALARM_MON }; | |
258 | struct i2c_msg msgs_in[] = { | |
259 | { | |
260 | .addr = client->addr, | |
261 | .flags = 0, | |
262 | .len = 1, | |
263 | .buf = dt_addr, | |
264 | }, | |
265 | { | |
266 | .addr = client->addr, | |
267 | .flags = I2C_M_RD, | |
268 | .len = M41T80_ALARM_REG_SIZE, | |
269 | .buf = buf, | |
270 | }, | |
271 | }; | |
272 | struct i2c_msg msgs[] = { | |
273 | { | |
274 | .addr = client->addr, | |
275 | .flags = 0, | |
276 | .len = 1 + M41T80_ALARM_REG_SIZE, | |
277 | .buf = wbuf, | |
278 | }, | |
279 | }; | |
280 | ||
281 | if (i2c_transfer(client->adapter, msgs_in, 2) < 0) { | |
282 | dev_err(&client->dev, "read error\n"); | |
283 | return -EIO; | |
284 | } | |
285 | reg[M41T80_REG_ALARM_MON] &= ~(0x1f | M41T80_ALMON_AFE); | |
286 | reg[M41T80_REG_ALARM_DAY] = 0; | |
287 | reg[M41T80_REG_ALARM_HOUR] &= ~(0x3f | 0x80); | |
288 | reg[M41T80_REG_ALARM_MIN] = 0; | |
289 | reg[M41T80_REG_ALARM_SEC] = 0; | |
290 | ||
291 | wbuf[0] = M41T80_REG_ALARM_MON; /* offset into rtc's regs */ | |
292 | reg[M41T80_REG_ALARM_SEC] |= t->time.tm_sec >= 0 ? | |
fe20ba70 | 293 | bin2bcd(t->time.tm_sec) : 0x80; |
caaff562 | 294 | reg[M41T80_REG_ALARM_MIN] |= t->time.tm_min >= 0 ? |
fe20ba70 | 295 | bin2bcd(t->time.tm_min) : 0x80; |
caaff562 | 296 | reg[M41T80_REG_ALARM_HOUR] |= t->time.tm_hour >= 0 ? |
fe20ba70 | 297 | bin2bcd(t->time.tm_hour) : 0x80; |
caaff562 | 298 | reg[M41T80_REG_ALARM_DAY] |= t->time.tm_mday >= 0 ? |
fe20ba70 | 299 | bin2bcd(t->time.tm_mday) : 0x80; |
caaff562 | 300 | if (t->time.tm_mon >= 0) |
fe20ba70 | 301 | reg[M41T80_REG_ALARM_MON] |= bin2bcd(t->time.tm_mon + 1); |
caaff562 AN |
302 | else |
303 | reg[M41T80_REG_ALARM_DAY] |= 0x40; | |
304 | ||
305 | if (i2c_transfer(client->adapter, msgs, 1) != 1) { | |
306 | dev_err(&client->dev, "write error\n"); | |
307 | return -EIO; | |
308 | } | |
309 | ||
310 | if (t->enabled) { | |
311 | reg[M41T80_REG_ALARM_MON] |= M41T80_ALMON_AFE; | |
312 | if (i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, | |
313 | reg[M41T80_REG_ALARM_MON]) < 0) { | |
314 | dev_err(&client->dev, "write error\n"); | |
315 | return -EIO; | |
316 | } | |
317 | } | |
318 | return 0; | |
319 | } | |
320 | ||
321 | static int m41t80_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *t) | |
322 | { | |
323 | struct i2c_client *client = to_i2c_client(dev); | |
324 | u8 buf[M41T80_ALARM_REG_SIZE + 1]; /* all alarm regs and flags */ | |
325 | u8 dt_addr[1] = { M41T80_REG_ALARM_MON }; | |
326 | u8 *reg = buf - M41T80_REG_ALARM_MON; | |
327 | struct i2c_msg msgs[] = { | |
328 | { | |
329 | .addr = client->addr, | |
330 | .flags = 0, | |
331 | .len = 1, | |
332 | .buf = dt_addr, | |
333 | }, | |
334 | { | |
335 | .addr = client->addr, | |
336 | .flags = I2C_M_RD, | |
337 | .len = M41T80_ALARM_REG_SIZE + 1, | |
338 | .buf = buf, | |
339 | }, | |
340 | }; | |
341 | ||
342 | if (i2c_transfer(client->adapter, msgs, 2) < 0) { | |
343 | dev_err(&client->dev, "read error\n"); | |
344 | return -EIO; | |
345 | } | |
346 | t->time.tm_sec = -1; | |
347 | t->time.tm_min = -1; | |
348 | t->time.tm_hour = -1; | |
349 | t->time.tm_mday = -1; | |
350 | t->time.tm_mon = -1; | |
351 | if (!(reg[M41T80_REG_ALARM_SEC] & 0x80)) | |
fe20ba70 | 352 | t->time.tm_sec = bcd2bin(reg[M41T80_REG_ALARM_SEC] & 0x7f); |
caaff562 | 353 | if (!(reg[M41T80_REG_ALARM_MIN] & 0x80)) |
fe20ba70 | 354 | t->time.tm_min = bcd2bin(reg[M41T80_REG_ALARM_MIN] & 0x7f); |
caaff562 | 355 | if (!(reg[M41T80_REG_ALARM_HOUR] & 0x80)) |
fe20ba70 | 356 | t->time.tm_hour = bcd2bin(reg[M41T80_REG_ALARM_HOUR] & 0x3f); |
caaff562 | 357 | if (!(reg[M41T80_REG_ALARM_DAY] & 0x80)) |
fe20ba70 | 358 | t->time.tm_mday = bcd2bin(reg[M41T80_REG_ALARM_DAY] & 0x3f); |
caaff562 | 359 | if (!(reg[M41T80_REG_ALARM_DAY] & 0x40)) |
fe20ba70 | 360 | t->time.tm_mon = bcd2bin(reg[M41T80_REG_ALARM_MON] & 0x1f) - 1; |
caaff562 AN |
361 | t->time.tm_year = -1; |
362 | t->time.tm_wday = -1; | |
363 | t->time.tm_yday = -1; | |
364 | t->time.tm_isdst = -1; | |
365 | t->enabled = !!(reg[M41T80_REG_ALARM_MON] & M41T80_ALMON_AFE); | |
366 | t->pending = !!(reg[M41T80_REG_FLAGS] & M41T80_FLAGS_AF); | |
367 | return 0; | |
368 | } | |
369 | ||
370 | static struct rtc_class_ops m41t80_rtc_ops = { | |
371 | .read_time = m41t80_rtc_read_time, | |
372 | .set_time = m41t80_rtc_set_time, | |
373 | .read_alarm = m41t80_rtc_read_alarm, | |
374 | .set_alarm = m41t80_rtc_set_alarm, | |
375 | .proc = m41t80_rtc_proc, | |
376 | .ioctl = m41t80_rtc_ioctl, | |
377 | }; | |
378 | ||
379 | #if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE) | |
380 | static ssize_t m41t80_sysfs_show_flags(struct device *dev, | |
381 | struct device_attribute *attr, char *buf) | |
382 | { | |
383 | struct i2c_client *client = to_i2c_client(dev); | |
384 | int val; | |
385 | ||
386 | val = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS); | |
387 | if (val < 0) | |
388 | return -EIO; | |
389 | return sprintf(buf, "%#x\n", val); | |
390 | } | |
391 | static DEVICE_ATTR(flags, S_IRUGO, m41t80_sysfs_show_flags, NULL); | |
392 | ||
393 | static ssize_t m41t80_sysfs_show_sqwfreq(struct device *dev, | |
394 | struct device_attribute *attr, char *buf) | |
395 | { | |
396 | struct i2c_client *client = to_i2c_client(dev); | |
d3a126fc | 397 | struct m41t80_data *clientdata = i2c_get_clientdata(client); |
f30281f4 | 398 | int val, reg_sqw; |
caaff562 | 399 | |
d3a126fc SF |
400 | if (!(clientdata->features & M41T80_FEATURE_SQ)) |
401 | return -EINVAL; | |
402 | ||
f30281f4 DG |
403 | reg_sqw = M41T80_REG_SQW; |
404 | if (clientdata->features & M41T80_FEATURE_SQ_ALT) | |
405 | reg_sqw = M41T80_REG_WDAY; | |
406 | val = i2c_smbus_read_byte_data(client, reg_sqw); | |
caaff562 AN |
407 | if (val < 0) |
408 | return -EIO; | |
409 | val = (val >> 4) & 0xf; | |
410 | switch (val) { | |
411 | case 0: | |
412 | break; | |
413 | case 1: | |
414 | val = 32768; | |
415 | break; | |
416 | default: | |
417 | val = 32768 >> val; | |
418 | } | |
419 | return sprintf(buf, "%d\n", val); | |
420 | } | |
421 | static ssize_t m41t80_sysfs_set_sqwfreq(struct device *dev, | |
422 | struct device_attribute *attr, | |
423 | const char *buf, size_t count) | |
424 | { | |
425 | struct i2c_client *client = to_i2c_client(dev); | |
d3a126fc | 426 | struct m41t80_data *clientdata = i2c_get_clientdata(client); |
f30281f4 | 427 | int almon, sqw, reg_sqw; |
caaff562 AN |
428 | int val = simple_strtoul(buf, NULL, 0); |
429 | ||
d3a126fc SF |
430 | if (!(clientdata->features & M41T80_FEATURE_SQ)) |
431 | return -EINVAL; | |
432 | ||
caaff562 AN |
433 | if (val) { |
434 | if (!is_power_of_2(val)) | |
435 | return -EINVAL; | |
436 | val = ilog2(val); | |
437 | if (val == 15) | |
438 | val = 1; | |
439 | else if (val < 14) | |
440 | val = 15 - val; | |
441 | else | |
442 | return -EINVAL; | |
443 | } | |
444 | /* disable SQW, set SQW frequency & re-enable */ | |
445 | almon = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON); | |
446 | if (almon < 0) | |
447 | return -EIO; | |
f30281f4 DG |
448 | reg_sqw = M41T80_REG_SQW; |
449 | if (clientdata->features & M41T80_FEATURE_SQ_ALT) | |
450 | reg_sqw = M41T80_REG_WDAY; | |
451 | sqw = i2c_smbus_read_byte_data(client, reg_sqw); | |
caaff562 AN |
452 | if (sqw < 0) |
453 | return -EIO; | |
454 | sqw = (sqw & 0x0f) | (val << 4); | |
455 | if (i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, | |
456 | almon & ~M41T80_ALMON_SQWE) < 0 || | |
f30281f4 | 457 | i2c_smbus_write_byte_data(client, reg_sqw, sqw) < 0) |
caaff562 AN |
458 | return -EIO; |
459 | if (val && i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, | |
460 | almon | M41T80_ALMON_SQWE) < 0) | |
461 | return -EIO; | |
462 | return count; | |
463 | } | |
464 | static DEVICE_ATTR(sqwfreq, S_IRUGO | S_IWUSR, | |
465 | m41t80_sysfs_show_sqwfreq, m41t80_sysfs_set_sqwfreq); | |
466 | ||
467 | static struct attribute *attrs[] = { | |
468 | &dev_attr_flags.attr, | |
469 | &dev_attr_sqwfreq.attr, | |
470 | NULL, | |
471 | }; | |
472 | static struct attribute_group attr_group = { | |
473 | .attrs = attrs, | |
474 | }; | |
475 | ||
476 | static int m41t80_sysfs_register(struct device *dev) | |
477 | { | |
478 | return sysfs_create_group(&dev->kobj, &attr_group); | |
479 | } | |
480 | #else | |
481 | static int m41t80_sysfs_register(struct device *dev) | |
482 | { | |
483 | return 0; | |
484 | } | |
485 | #endif | |
486 | ||
617780d2 AN |
487 | #ifdef CONFIG_RTC_DRV_M41T80_WDT |
488 | /* | |
489 | ***************************************************************************** | |
490 | * | |
491 | * Watchdog Driver | |
492 | * | |
493 | ***************************************************************************** | |
494 | */ | |
495 | static struct i2c_client *save_client; | |
496 | ||
497 | /* Default margin */ | |
498 | #define WD_TIMO 60 /* 1..31 seconds */ | |
499 | ||
500 | static int wdt_margin = WD_TIMO; | |
501 | module_param(wdt_margin, int, 0); | |
502 | MODULE_PARM_DESC(wdt_margin, "Watchdog timeout in seconds (default 60s)"); | |
503 | ||
504 | static unsigned long wdt_is_open; | |
505 | static int boot_flag; | |
506 | ||
507 | /** | |
508 | * wdt_ping: | |
509 | * | |
510 | * Reload counter one with the watchdog timeout. We don't bother reloading | |
511 | * the cascade counter. | |
512 | */ | |
513 | static void wdt_ping(void) | |
514 | { | |
515 | unsigned char i2c_data[2]; | |
516 | struct i2c_msg msgs1[1] = { | |
517 | { | |
518 | .addr = save_client->addr, | |
519 | .flags = 0, | |
520 | .len = 2, | |
521 | .buf = i2c_data, | |
522 | }, | |
523 | }; | |
d3a126fc SF |
524 | struct m41t80_data *clientdata = i2c_get_clientdata(save_client); |
525 | ||
617780d2 AN |
526 | i2c_data[0] = 0x09; /* watchdog register */ |
527 | ||
528 | if (wdt_margin > 31) | |
529 | i2c_data[1] = (wdt_margin & 0xFC) | 0x83; /* resolution = 4s */ | |
530 | else | |
531 | /* | |
532 | * WDS = 1 (0x80), mulitplier = WD_TIMO, resolution = 1s (0x02) | |
533 | */ | |
534 | i2c_data[1] = wdt_margin<<2 | 0x82; | |
535 | ||
d3a126fc SF |
536 | /* |
537 | * M41T65 has three bits for watchdog resolution. Don't set bit 7, as | |
538 | * that would be an invalid resolution. | |
539 | */ | |
540 | if (clientdata->features & M41T80_FEATURE_WD) | |
541 | i2c_data[1] &= ~M41T80_WATCHDOG_RB2; | |
542 | ||
617780d2 AN |
543 | i2c_transfer(save_client->adapter, msgs1, 1); |
544 | } | |
545 | ||
546 | /** | |
547 | * wdt_disable: | |
548 | * | |
549 | * disables watchdog. | |
550 | */ | |
551 | static void wdt_disable(void) | |
552 | { | |
553 | unsigned char i2c_data[2], i2c_buf[0x10]; | |
554 | struct i2c_msg msgs0[2] = { | |
555 | { | |
556 | .addr = save_client->addr, | |
557 | .flags = 0, | |
558 | .len = 1, | |
559 | .buf = i2c_data, | |
560 | }, | |
561 | { | |
562 | .addr = save_client->addr, | |
563 | .flags = I2C_M_RD, | |
564 | .len = 1, | |
565 | .buf = i2c_buf, | |
566 | }, | |
567 | }; | |
568 | struct i2c_msg msgs1[1] = { | |
569 | { | |
570 | .addr = save_client->addr, | |
571 | .flags = 0, | |
572 | .len = 2, | |
573 | .buf = i2c_data, | |
574 | }, | |
575 | }; | |
576 | ||
577 | i2c_data[0] = 0x09; | |
578 | i2c_transfer(save_client->adapter, msgs0, 2); | |
579 | ||
580 | i2c_data[0] = 0x09; | |
581 | i2c_data[1] = 0x00; | |
582 | i2c_transfer(save_client->adapter, msgs1, 1); | |
583 | } | |
584 | ||
585 | /** | |
586 | * wdt_write: | |
587 | * @file: file handle to the watchdog | |
588 | * @buf: buffer to write (unused as data does not matter here | |
589 | * @count: count of bytes | |
590 | * @ppos: pointer to the position to write. No seeks allowed | |
591 | * | |
592 | * A write to a watchdog device is defined as a keepalive signal. Any | |
593 | * write of data will do, as we we don't define content meaning. | |
594 | */ | |
595 | static ssize_t wdt_write(struct file *file, const char __user *buf, | |
596 | size_t count, loff_t *ppos) | |
597 | { | |
598 | /* Can't seek (pwrite) on this device | |
599 | if (ppos != &file->f_pos) | |
600 | return -ESPIPE; | |
601 | */ | |
602 | if (count) { | |
603 | wdt_ping(); | |
604 | return 1; | |
605 | } | |
606 | return 0; | |
607 | } | |
608 | ||
609 | static ssize_t wdt_read(struct file *file, char __user *buf, | |
610 | size_t count, loff_t *ppos) | |
611 | { | |
612 | return 0; | |
613 | } | |
614 | ||
615 | /** | |
616 | * wdt_ioctl: | |
617 | * @inode: inode of the device | |
618 | * @file: file handle to the device | |
619 | * @cmd: watchdog command | |
620 | * @arg: argument pointer | |
621 | * | |
622 | * The watchdog API defines a common set of functions for all watchdogs | |
623 | * according to their available features. We only actually usefully support | |
624 | * querying capabilities and current status. | |
625 | */ | |
626 | static int wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, | |
627 | unsigned long arg) | |
628 | { | |
629 | int new_margin, rv; | |
630 | static struct watchdog_info ident = { | |
631 | .options = WDIOF_POWERUNDER | WDIOF_KEEPALIVEPING | | |
632 | WDIOF_SETTIMEOUT, | |
633 | .firmware_version = 1, | |
634 | .identity = "M41T80 WTD" | |
635 | }; | |
636 | ||
637 | switch (cmd) { | |
638 | case WDIOC_GETSUPPORT: | |
639 | return copy_to_user((struct watchdog_info __user *)arg, &ident, | |
640 | sizeof(ident)) ? -EFAULT : 0; | |
641 | ||
642 | case WDIOC_GETSTATUS: | |
643 | case WDIOC_GETBOOTSTATUS: | |
644 | return put_user(boot_flag, (int __user *)arg); | |
645 | case WDIOC_KEEPALIVE: | |
646 | wdt_ping(); | |
647 | return 0; | |
648 | case WDIOC_SETTIMEOUT: | |
649 | if (get_user(new_margin, (int __user *)arg)) | |
650 | return -EFAULT; | |
651 | /* Arbitrary, can't find the card's limits */ | |
652 | if (new_margin < 1 || new_margin > 124) | |
653 | return -EINVAL; | |
654 | wdt_margin = new_margin; | |
655 | wdt_ping(); | |
656 | /* Fall */ | |
657 | case WDIOC_GETTIMEOUT: | |
658 | return put_user(wdt_margin, (int __user *)arg); | |
659 | ||
660 | case WDIOC_SETOPTIONS: | |
661 | if (copy_from_user(&rv, (int __user *)arg, sizeof(int))) | |
662 | return -EFAULT; | |
663 | ||
664 | if (rv & WDIOS_DISABLECARD) { | |
4c228db0 | 665 | pr_info("rtc-m41t80: disable watchdog\n"); |
617780d2 AN |
666 | wdt_disable(); |
667 | } | |
668 | ||
669 | if (rv & WDIOS_ENABLECARD) { | |
4c228db0 | 670 | pr_info("rtc-m41t80: enable watchdog\n"); |
617780d2 AN |
671 | wdt_ping(); |
672 | } | |
673 | ||
674 | return -EINVAL; | |
675 | } | |
676 | return -ENOTTY; | |
677 | } | |
678 | ||
679 | /** | |
680 | * wdt_open: | |
681 | * @inode: inode of device | |
682 | * @file: file handle to device | |
683 | * | |
684 | */ | |
685 | static int wdt_open(struct inode *inode, struct file *file) | |
686 | { | |
687 | if (MINOR(inode->i_rdev) == WATCHDOG_MINOR) { | |
41012735 AB |
688 | lock_kernel(); |
689 | if (test_and_set_bit(0, &wdt_is_open)) { | |
690 | unlock_kernel(); | |
617780d2 | 691 | return -EBUSY; |
41012735 | 692 | } |
617780d2 AN |
693 | /* |
694 | * Activate | |
695 | */ | |
696 | wdt_is_open = 1; | |
41012735 | 697 | unlock_kernel(); |
617780d2 AN |
698 | return 0; |
699 | } | |
700 | return -ENODEV; | |
701 | } | |
702 | ||
703 | /** | |
704 | * wdt_close: | |
705 | * @inode: inode to board | |
706 | * @file: file handle to board | |
707 | * | |
708 | */ | |
709 | static int wdt_release(struct inode *inode, struct file *file) | |
710 | { | |
711 | if (MINOR(inode->i_rdev) == WATCHDOG_MINOR) | |
712 | clear_bit(0, &wdt_is_open); | |
713 | return 0; | |
714 | } | |
715 | ||
716 | /** | |
717 | * notify_sys: | |
718 | * @this: our notifier block | |
719 | * @code: the event being reported | |
720 | * @unused: unused | |
721 | * | |
722 | * Our notifier is called on system shutdowns. We want to turn the card | |
723 | * off at reboot otherwise the machine will reboot again during memory | |
724 | * test or worse yet during the following fsck. This would suck, in fact | |
725 | * trust me - if it happens it does suck. | |
726 | */ | |
727 | static int wdt_notify_sys(struct notifier_block *this, unsigned long code, | |
728 | void *unused) | |
729 | { | |
730 | if (code == SYS_DOWN || code == SYS_HALT) | |
731 | /* Disable Watchdog */ | |
732 | wdt_disable(); | |
733 | return NOTIFY_DONE; | |
734 | } | |
735 | ||
736 | static const struct file_operations wdt_fops = { | |
737 | .owner = THIS_MODULE, | |
738 | .read = wdt_read, | |
739 | .ioctl = wdt_ioctl, | |
740 | .write = wdt_write, | |
741 | .open = wdt_open, | |
742 | .release = wdt_release, | |
743 | }; | |
744 | ||
745 | static struct miscdevice wdt_dev = { | |
746 | .minor = WATCHDOG_MINOR, | |
747 | .name = "watchdog", | |
748 | .fops = &wdt_fops, | |
749 | }; | |
750 | ||
751 | /* | |
752 | * The WDT card needs to learn about soft shutdowns in order to | |
753 | * turn the timebomb registers off. | |
754 | */ | |
755 | static struct notifier_block wdt_notifier = { | |
756 | .notifier_call = wdt_notify_sys, | |
757 | }; | |
758 | #endif /* CONFIG_RTC_DRV_M41T80_WDT */ | |
759 | ||
caaff562 AN |
760 | /* |
761 | ***************************************************************************** | |
762 | * | |
763 | * Driver Interface | |
764 | * | |
765 | ***************************************************************************** | |
766 | */ | |
d2653e92 JD |
767 | static int m41t80_probe(struct i2c_client *client, |
768 | const struct i2c_device_id *id) | |
caaff562 | 769 | { |
3760f736 | 770 | int rc = 0; |
caaff562 AN |
771 | struct rtc_device *rtc = NULL; |
772 | struct rtc_time tm; | |
caaff562 AN |
773 | struct m41t80_data *clientdata = NULL; |
774 | ||
775 | if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | |
776 | | I2C_FUNC_SMBUS_BYTE_DATA)) { | |
777 | rc = -ENODEV; | |
778 | goto exit; | |
779 | } | |
780 | ||
781 | dev_info(&client->dev, | |
782 | "chip found, driver version " DRV_VERSION "\n"); | |
783 | ||
caaff562 AN |
784 | clientdata = kzalloc(sizeof(*clientdata), GFP_KERNEL); |
785 | if (!clientdata) { | |
786 | rc = -ENOMEM; | |
787 | goto exit; | |
788 | } | |
789 | ||
790 | rtc = rtc_device_register(client->name, &client->dev, | |
791 | &m41t80_rtc_ops, THIS_MODULE); | |
792 | if (IS_ERR(rtc)) { | |
793 | rc = PTR_ERR(rtc); | |
794 | rtc = NULL; | |
795 | goto exit; | |
796 | } | |
797 | ||
798 | clientdata->rtc = rtc; | |
3760f736 | 799 | clientdata->features = id->driver_data; |
caaff562 AN |
800 | i2c_set_clientdata(client, clientdata); |
801 | ||
802 | /* Make sure HT (Halt Update) bit is cleared */ | |
803 | rc = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_HOUR); | |
804 | if (rc < 0) | |
805 | goto ht_err; | |
806 | ||
807 | if (rc & M41T80_ALHOUR_HT) { | |
3760f736 | 808 | if (clientdata->features & M41T80_FEATURE_HT) { |
caaff562 AN |
809 | m41t80_get_datetime(client, &tm); |
810 | dev_info(&client->dev, "HT bit was set!\n"); | |
811 | dev_info(&client->dev, | |
812 | "Power Down at " | |
813 | "%04i-%02i-%02i %02i:%02i:%02i\n", | |
814 | tm.tm_year + 1900, | |
815 | tm.tm_mon + 1, tm.tm_mday, tm.tm_hour, | |
816 | tm.tm_min, tm.tm_sec); | |
817 | } | |
818 | if (i2c_smbus_write_byte_data(client, | |
819 | M41T80_REG_ALARM_HOUR, | |
820 | rc & ~M41T80_ALHOUR_HT) < 0) | |
821 | goto ht_err; | |
822 | } | |
823 | ||
824 | /* Make sure ST (stop) bit is cleared */ | |
825 | rc = i2c_smbus_read_byte_data(client, M41T80_REG_SEC); | |
826 | if (rc < 0) | |
827 | goto st_err; | |
828 | ||
829 | if (rc & M41T80_SEC_ST) { | |
830 | if (i2c_smbus_write_byte_data(client, M41T80_REG_SEC, | |
831 | rc & ~M41T80_SEC_ST) < 0) | |
832 | goto st_err; | |
833 | } | |
834 | ||
835 | rc = m41t80_sysfs_register(&client->dev); | |
836 | if (rc) | |
837 | goto exit; | |
838 | ||
617780d2 | 839 | #ifdef CONFIG_RTC_DRV_M41T80_WDT |
3760f736 | 840 | if (clientdata->features & M41T80_FEATURE_HT) { |
417607d0 | 841 | save_client = client; |
617780d2 AN |
842 | rc = misc_register(&wdt_dev); |
843 | if (rc) | |
844 | goto exit; | |
845 | rc = register_reboot_notifier(&wdt_notifier); | |
846 | if (rc) { | |
847 | misc_deregister(&wdt_dev); | |
848 | goto exit; | |
849 | } | |
617780d2 AN |
850 | } |
851 | #endif | |
caaff562 AN |
852 | return 0; |
853 | ||
854 | st_err: | |
855 | rc = -EIO; | |
856 | dev_err(&client->dev, "Can't clear ST bit\n"); | |
857 | goto exit; | |
858 | ht_err: | |
859 | rc = -EIO; | |
860 | dev_err(&client->dev, "Can't clear HT bit\n"); | |
861 | goto exit; | |
862 | ||
863 | exit: | |
864 | if (rtc) | |
865 | rtc_device_unregister(rtc); | |
866 | kfree(clientdata); | |
867 | return rc; | |
868 | } | |
869 | ||
870 | static int m41t80_remove(struct i2c_client *client) | |
871 | { | |
872 | struct m41t80_data *clientdata = i2c_get_clientdata(client); | |
873 | struct rtc_device *rtc = clientdata->rtc; | |
874 | ||
617780d2 | 875 | #ifdef CONFIG_RTC_DRV_M41T80_WDT |
3760f736 | 876 | if (clientdata->features & M41T80_FEATURE_HT) { |
617780d2 AN |
877 | misc_deregister(&wdt_dev); |
878 | unregister_reboot_notifier(&wdt_notifier); | |
879 | } | |
880 | #endif | |
caaff562 AN |
881 | if (rtc) |
882 | rtc_device_unregister(rtc); | |
883 | kfree(clientdata); | |
884 | ||
885 | return 0; | |
886 | } | |
887 | ||
888 | static struct i2c_driver m41t80_driver = { | |
889 | .driver = { | |
afe1ab4d | 890 | .name = "rtc-m41t80", |
caaff562 AN |
891 | }, |
892 | .probe = m41t80_probe, | |
893 | .remove = m41t80_remove, | |
3760f736 | 894 | .id_table = m41t80_id, |
caaff562 AN |
895 | }; |
896 | ||
897 | static int __init m41t80_rtc_init(void) | |
898 | { | |
899 | return i2c_add_driver(&m41t80_driver); | |
900 | } | |
901 | ||
902 | static void __exit m41t80_rtc_exit(void) | |
903 | { | |
904 | i2c_del_driver(&m41t80_driver); | |
905 | } | |
906 | ||
907 | MODULE_AUTHOR("Alexander Bigga <ab@mycable.de>"); | |
908 | MODULE_DESCRIPTION("ST Microelectronics M41T80 series RTC I2C Client Driver"); | |
909 | MODULE_LICENSE("GPL"); | |
910 | MODULE_VERSION(DRV_VERSION); | |
911 | ||
912 | module_init(m41t80_rtc_init); | |
913 | module_exit(m41t80_rtc_exit); |