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Diffstat (limited to 'drivers/i2c/chips/m41t00.c')
-rw-r--r--drivers/i2c/chips/m41t00.c346
1 files changed, 254 insertions, 92 deletions
diff --git a/drivers/i2c/chips/m41t00.c b/drivers/i2c/chips/m41t00.c
index 99ab4ec34390..2dd0a34d9472 100644
--- a/drivers/i2c/chips/m41t00.c
+++ b/drivers/i2c/chips/m41t00.c
@@ -1,11 +1,9 @@
1/* 1/*
2 * drivers/i2c/chips/m41t00.c 2 * I2C client/driver for the ST M41T00 family of i2c rtc chips.
3 *
4 * I2C client/driver for the ST M41T00 Real-Time Clock chip.
5 * 3 *
6 * Author: Mark A. Greer <mgreer@mvista.com> 4 * Author: Mark A. Greer <mgreer@mvista.com>
7 * 5 *
8 * 2005 (c) MontaVista Software, Inc. This file is licensed under 6 * 2005, 2006 (c) MontaVista Software, Inc. This file is licensed under
9 * the terms of the GNU General Public License version 2. This program 7 * the terms of the GNU General Public License version 2. This program
10 * is licensed "as is" without any warranty of any kind, whether express 8 * is licensed "as is" without any warranty of any kind, whether express
11 * or implied. 9 * or implied.
@@ -13,9 +11,6 @@
13/* 11/*
14 * This i2c client/driver wedges between the drivers/char/genrtc.c RTC 12 * This i2c client/driver wedges between the drivers/char/genrtc.c RTC
15 * interface and the SMBus interface of the i2c subsystem. 13 * interface and the SMBus interface of the i2c subsystem.
16 * It would be more efficient to use i2c msgs/i2c_transfer directly but, as
17 * recommened in .../Documentation/i2c/writing-clients section
18 * "Sending and receiving", using SMBus level communication is preferred.
19 */ 14 */
20 15
21#include <linux/kernel.h> 16#include <linux/kernel.h>
@@ -24,56 +19,110 @@
24#include <linux/i2c.h> 19#include <linux/i2c.h>
25#include <linux/rtc.h> 20#include <linux/rtc.h>
26#include <linux/bcd.h> 21#include <linux/bcd.h>
27#include <linux/mutex.h>
28#include <linux/workqueue.h> 22#include <linux/workqueue.h>
29 23#include <linux/platform_device.h>
24#include <linux/m41t00.h>
30#include <asm/time.h> 25#include <asm/time.h>
31#include <asm/rtc.h> 26#include <asm/rtc.h>
32 27
33#define M41T00_DRV_NAME "m41t00"
34
35static DEFINE_MUTEX(m41t00_mutex);
36
37static struct i2c_driver m41t00_driver; 28static struct i2c_driver m41t00_driver;
38static struct i2c_client *save_client; 29static struct i2c_client *save_client;
39 30
40static unsigned short ignore[] = { I2C_CLIENT_END }; 31static unsigned short ignore[] = { I2C_CLIENT_END };
41static unsigned short normal_addr[] = { 0x68, I2C_CLIENT_END }; 32static unsigned short normal_addr[] = { I2C_CLIENT_END, I2C_CLIENT_END };
42 33
43static struct i2c_client_address_data addr_data = { 34static struct i2c_client_address_data addr_data = {
44 .normal_i2c = normal_addr, 35 .normal_i2c = normal_addr,
45 .probe = ignore, 36 .probe = ignore,
46 .ignore = ignore, 37 .ignore = ignore,
38};
39
40struct m41t00_chip_info {
41 u8 type;
42 char *name;
43 u8 read_limit;
44 u8 sec; /* Offsets for chip regs */
45 u8 min;
46 u8 hour;
47 u8 day;
48 u8 mon;
49 u8 year;
50 u8 alarm_mon;
51 u8 alarm_hour;
52 u8 sqw;
53 u8 sqw_freq;
47}; 54};
48 55
56static struct m41t00_chip_info m41t00_chip_info_tbl[] = {
57 {
58 .type = M41T00_TYPE_M41T00,
59 .name = "m41t00",
60 .read_limit = 5,
61 .sec = 0,
62 .min = 1,
63 .hour = 2,
64 .day = 4,
65 .mon = 5,
66 .year = 6,
67 },
68 {
69 .type = M41T00_TYPE_M41T81,
70 .name = "m41t81",
71 .read_limit = 1,
72 .sec = 1,
73 .min = 2,
74 .hour = 3,
75 .day = 5,
76 .mon = 6,
77 .year = 7,
78 .alarm_mon = 0xa,
79 .alarm_hour = 0xc,
80 .sqw = 0x13,
81 },
82 {
83 .type = M41T00_TYPE_M41T85,
84 .name = "m41t85",
85 .read_limit = 1,
86 .sec = 1,
87 .min = 2,
88 .hour = 3,
89 .day = 5,
90 .mon = 6,
91 .year = 7,
92 .alarm_mon = 0xa,
93 .alarm_hour = 0xc,
94 .sqw = 0x13,
95 },
96};
97static struct m41t00_chip_info *m41t00_chip;
98
49ulong 99ulong
50m41t00_get_rtc_time(void) 100m41t00_get_rtc_time(void)
51{ 101{
52 s32 sec, min, hour, day, mon, year; 102 s32 sec, min, hour, day, mon, year;
53 s32 sec1, min1, hour1, day1, mon1, year1; 103 s32 sec1, min1, hour1, day1, mon1, year1;
54 ulong limit = 10; 104 u8 reads = 0;
105 u8 buf[8], msgbuf[1] = { 0 }; /* offset into rtc's regs */
106 struct i2c_msg msgs[] = {
107 {
108 .addr = save_client->addr,
109 .flags = 0,
110 .len = 1,
111 .buf = msgbuf,
112 },
113 {
114 .addr = save_client->addr,
115 .flags = I2C_M_RD,
116 .len = 8,
117 .buf = buf,
118 },
119 };
55 120
56 sec = min = hour = day = mon = year = 0; 121 sec = min = hour = day = mon = year = 0;
57 sec1 = min1 = hour1 = day1 = mon1 = year1 = 0;
58 122
59 mutex_lock(&m41t00_mutex);
60 do { 123 do {
61 if (((sec = i2c_smbus_read_byte_data(save_client, 0)) >= 0) 124 if (i2c_transfer(save_client->adapter, msgs, 2) < 0)
62 && ((min = i2c_smbus_read_byte_data(save_client, 1)) 125 goto read_err;
63 >= 0)
64 && ((hour = i2c_smbus_read_byte_data(save_client, 2))
65 >= 0)
66 && ((day = i2c_smbus_read_byte_data(save_client, 4))
67 >= 0)
68 && ((mon = i2c_smbus_read_byte_data(save_client, 5))
69 >= 0)
70 && ((year = i2c_smbus_read_byte_data(save_client, 6))
71 >= 0)
72 && ((sec == sec1) && (min == min1) && (hour == hour1)
73 && (day == day1) && (mon == mon1)
74 && (year == year1)))
75
76 break;
77 126
78 sec1 = sec; 127 sec1 = sec;
79 min1 = min; 128 min1 = min;
@@ -81,69 +130,88 @@ m41t00_get_rtc_time(void)
81 day1 = day; 130 day1 = day;
82 mon1 = mon; 131 mon1 = mon;
83 year1 = year; 132 year1 = year;
84 } while (--limit > 0);
85 mutex_unlock(&m41t00_mutex);
86
87 if (limit == 0) {
88 dev_warn(&save_client->dev,
89 "m41t00: can't read rtc chip\n");
90 sec = min = hour = day = mon = year = 0;
91 }
92
93 sec &= 0x7f;
94 min &= 0x7f;
95 hour &= 0x3f;
96 day &= 0x3f;
97 mon &= 0x1f;
98 year &= 0xff;
99 133
100 BCD_TO_BIN(sec); 134 sec = buf[m41t00_chip->sec] & 0x7f;
101 BCD_TO_BIN(min); 135 min = buf[m41t00_chip->min] & 0x7f;
102 BCD_TO_BIN(hour); 136 hour = buf[m41t00_chip->hour] & 0x3f;
103 BCD_TO_BIN(day); 137 day = buf[m41t00_chip->day] & 0x3f;
104 BCD_TO_BIN(mon); 138 mon = buf[m41t00_chip->mon] & 0x1f;
105 BCD_TO_BIN(year); 139 year = buf[m41t00_chip->year];
140 } while ((++reads < m41t00_chip->read_limit) && ((sec != sec1)
141 || (min != min1) || (hour != hour1) || (day != day1)
142 || (mon != mon1) || (year != year1)));
143
144 if ((m41t00_chip->read_limit > 1) && ((sec != sec1) || (min != min1)
145 || (hour != hour1) || (day != day1) || (mon != mon1)
146 || (year != year1)))
147 goto read_err;
148
149 sec = BCD2BIN(sec);
150 min = BCD2BIN(min);
151 hour = BCD2BIN(hour);
152 day = BCD2BIN(day);
153 mon = BCD2BIN(mon);
154 year = BCD2BIN(year);
106 155
107 year += 1900; 156 year += 1900;
108 if (year < 1970) 157 if (year < 1970)
109 year += 100; 158 year += 100;
110 159
111 return mktime(year, mon, day, hour, min, sec); 160 return mktime(year, mon, day, hour, min, sec);
161
162read_err:
163 dev_err(&save_client->dev, "m41t00_get_rtc_time: Read error\n");
164 return 0;
112} 165}
166EXPORT_SYMBOL_GPL(m41t00_get_rtc_time);
113 167
114static void 168static void
115m41t00_set(void *arg) 169m41t00_set(void *arg)
116{ 170{
117 struct rtc_time tm; 171 struct rtc_time tm;
118 ulong nowtime = *(ulong *)arg; 172 int nowtime = *(int *)arg;
173 s32 sec, min, hour, day, mon, year;
174 u8 wbuf[9], *buf = &wbuf[1], msgbuf[1] = { 0 };
175 struct i2c_msg msgs[] = {
176 {
177 .addr = save_client->addr,
178 .flags = 0,
179 .len = 1,
180 .buf = msgbuf,
181 },
182 {
183 .addr = save_client->addr,
184 .flags = I2C_M_RD,
185 .len = 8,
186 .buf = buf,
187 },
188 };
119 189
120 to_tm(nowtime, &tm); 190 to_tm(nowtime, &tm);
121 tm.tm_year = (tm.tm_year - 1900) % 100; 191 tm.tm_year = (tm.tm_year - 1900) % 100;
122 192
123 BIN_TO_BCD(tm.tm_sec); 193 sec = BIN2BCD(tm.tm_sec);
124 BIN_TO_BCD(tm.tm_min); 194 min = BIN2BCD(tm.tm_min);
125 BIN_TO_BCD(tm.tm_hour); 195 hour = BIN2BCD(tm.tm_hour);
126 BIN_TO_BCD(tm.tm_mon); 196 day = BIN2BCD(tm.tm_mday);
127 BIN_TO_BCD(tm.tm_mday); 197 mon = BIN2BCD(tm.tm_mon);
128 BIN_TO_BCD(tm.tm_year); 198 year = BIN2BCD(tm.tm_year);
129 199
130 mutex_lock(&m41t00_mutex); 200 /* Read reg values into buf[0..7]/wbuf[1..8] */
131 if ((i2c_smbus_write_byte_data(save_client, 0, tm.tm_sec & 0x7f) < 0) 201 if (i2c_transfer(save_client->adapter, msgs, 2) < 0) {
132 || (i2c_smbus_write_byte_data(save_client, 1, tm.tm_min & 0x7f) 202 dev_err(&save_client->dev, "m41t00_set: Read error\n");
133 < 0) 203 return;
134 || (i2c_smbus_write_byte_data(save_client, 2, tm.tm_hour & 0x3f) 204 }
135 < 0) 205
136 || (i2c_smbus_write_byte_data(save_client, 4, tm.tm_mday & 0x3f) 206 wbuf[0] = 0; /* offset into rtc's regs */
137 < 0) 207 buf[m41t00_chip->sec] = (buf[m41t00_chip->sec] & ~0x7f) | (sec & 0x7f);
138 || (i2c_smbus_write_byte_data(save_client, 5, tm.tm_mon & 0x1f) 208 buf[m41t00_chip->min] = (buf[m41t00_chip->min] & ~0x7f) | (min & 0x7f);
139 < 0) 209 buf[m41t00_chip->hour] = (buf[m41t00_chip->hour] & ~0x3f) | (hour& 0x3f);
140 || (i2c_smbus_write_byte_data(save_client, 6, tm.tm_year & 0xff) 210 buf[m41t00_chip->day] = (buf[m41t00_chip->day] & ~0x3f) | (day & 0x3f);
141 < 0)) 211 buf[m41t00_chip->mon] = (buf[m41t00_chip->mon] & ~0x1f) | (mon & 0x1f);
142 212
143 dev_warn(&save_client->dev,"m41t00: can't write to rtc chip\n"); 213 if (i2c_master_send(save_client, wbuf, 9) < 0)
144 214 dev_err(&save_client->dev, "m41t00_set: Write error\n");
145 mutex_unlock(&m41t00_mutex);
146 return;
147} 215}
148 216
149static ulong new_time; 217static ulong new_time;
@@ -162,6 +230,48 @@ m41t00_set_rtc_time(ulong nowtime)
162 230
163 return 0; 231 return 0;
164} 232}
233EXPORT_SYMBOL_GPL(m41t00_set_rtc_time);
234
235/*
236 *****************************************************************************
237 *
238 * platform_data Driver Interface
239 *
240 *****************************************************************************
241 */
242static int __init
243m41t00_platform_probe(struct platform_device *pdev)
244{
245 struct m41t00_platform_data *pdata;
246 int i;
247
248 if (pdev && (pdata = pdev->dev.platform_data)) {
249 normal_addr[0] = pdata->i2c_addr;
250
251 for (i=0; i<ARRAY_SIZE(m41t00_chip_info_tbl); i++)
252 if (m41t00_chip_info_tbl[i].type == pdata->type) {
253 m41t00_chip = &m41t00_chip_info_tbl[i];
254 m41t00_chip->sqw_freq = pdata->sqw_freq;
255 return 0;
256 }
257 }
258 return -ENODEV;
259}
260
261static int __exit
262m41t00_platform_remove(struct platform_device *pdev)
263{
264 return 0;
265}
266
267static struct platform_driver m41t00_platform_driver = {
268 .probe = m41t00_platform_probe,
269 .remove = m41t00_platform_remove,
270 .driver = {
271 .owner = THIS_MODULE,
272 .name = M41T00_DRV_NAME,
273 },
274};
165 275
166/* 276/*
167 ***************************************************************************** 277 *****************************************************************************
@@ -176,23 +286,71 @@ m41t00_probe(struct i2c_adapter *adap, int addr, int kind)
176 struct i2c_client *client; 286 struct i2c_client *client;
177 int rc; 287 int rc;
178 288
289 if (!i2c_check_functionality(adap, I2C_FUNC_I2C
290 | I2C_FUNC_SMBUS_BYTE_DATA))
291 return 0;
292
179 client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); 293 client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
180 if (!client) 294 if (!client)
181 return -ENOMEM; 295 return -ENOMEM;
182 296
183 strncpy(client->name, M41T00_DRV_NAME, I2C_NAME_SIZE); 297 strlcpy(client->name, m41t00_chip->name, I2C_NAME_SIZE);
184 client->addr = addr; 298 client->addr = addr;
185 client->adapter = adap; 299 client->adapter = adap;
186 client->driver = &m41t00_driver; 300 client->driver = &m41t00_driver;
187 301
188 if ((rc = i2c_attach_client(client)) != 0) { 302 if ((rc = i2c_attach_client(client)))
189 kfree(client); 303 goto attach_err;
190 return rc; 304
305 if (m41t00_chip->type != M41T00_TYPE_M41T00) {
306 /* If asked, disable SQW, set SQW frequency & re-enable */
307 if (m41t00_chip->sqw_freq)
308 if (((rc = i2c_smbus_read_byte_data(client,
309 m41t00_chip->alarm_mon)) < 0)
310 || ((rc = i2c_smbus_write_byte_data(client,
311 m41t00_chip->alarm_mon, rc & ~0x40)) <0)
312 || ((rc = i2c_smbus_write_byte_data(client,
313 m41t00_chip->sqw,
314 m41t00_chip->sqw_freq)) < 0)
315 || ((rc = i2c_smbus_write_byte_data(client,
316 m41t00_chip->alarm_mon, rc | 0x40)) <0))
317 goto sqw_err;
318
319 /* Make sure HT (Halt Update) bit is cleared */
320 if ((rc = i2c_smbus_read_byte_data(client,
321 m41t00_chip->alarm_hour)) < 0)
322 goto ht_err;
323
324 if (rc & 0x40)
325 if ((rc = i2c_smbus_write_byte_data(client,
326 m41t00_chip->alarm_hour, rc & ~0x40))<0)
327 goto ht_err;
191 } 328 }
192 329
193 m41t00_wq = create_singlethread_workqueue("m41t00"); 330 /* Make sure ST (stop) bit is cleared */
331 if ((rc = i2c_smbus_read_byte_data(client, m41t00_chip->sec)) < 0)
332 goto st_err;
333
334 if (rc & 0x80)
335 if ((rc = i2c_smbus_write_byte_data(client, m41t00_chip->sec,
336 rc & ~0x80)) < 0)
337 goto st_err;
338
339 m41t00_wq = create_singlethread_workqueue(m41t00_chip->name);
194 save_client = client; 340 save_client = client;
195 return 0; 341 return 0;
342
343st_err:
344 dev_err(&client->dev, "m41t00_probe: Can't clear ST bit\n");
345 goto attach_err;
346ht_err:
347 dev_err(&client->dev, "m41t00_probe: Can't clear HT bit\n");
348 goto attach_err;
349sqw_err:
350 dev_err(&client->dev, "m41t00_probe: Can't set SQW Frequency\n");
351attach_err:
352 kfree(client);
353 return rc;
196} 354}
197 355
198static int 356static int
@@ -204,7 +362,7 @@ m41t00_attach(struct i2c_adapter *adap)
204static int 362static int
205m41t00_detach(struct i2c_client *client) 363m41t00_detach(struct i2c_client *client)
206{ 364{
207 int rc; 365 int rc;
208 366
209 if ((rc = i2c_detach_client(client)) == 0) { 367 if ((rc = i2c_detach_client(client)) == 0) {
210 kfree(client); 368 kfree(client);
@@ -225,14 +383,18 @@ static struct i2c_driver m41t00_driver = {
225static int __init 383static int __init
226m41t00_init(void) 384m41t00_init(void)
227{ 385{
228 return i2c_add_driver(&m41t00_driver); 386 int rc;
387
388 if (!(rc = platform_driver_register(&m41t00_platform_driver)))
389 rc = i2c_add_driver(&m41t00_driver);
390 return rc;
229} 391}
230 392
231static void __exit 393static void __exit
232m41t00_exit(void) 394m41t00_exit(void)
233{ 395{
234 i2c_del_driver(&m41t00_driver); 396 i2c_del_driver(&m41t00_driver);
235 return; 397 platform_driver_unregister(&m41t00_platform_driver);
236} 398}
237 399
238module_init(m41t00_init); 400module_init(m41t00_init);
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-17 12:52:41 -0500