]>
Commit | Line | Data |
---|---|---|
edf1aaa3 AZ |
1 | /* |
2 | * An rtc/i2c driver for the Dallas DS1672 | |
3 | * Copyright 2005 Alessandro Zummo | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License version 2 as | |
7 | * published by the Free Software Foundation. | |
8 | */ | |
9 | ||
10 | #include <linux/module.h> | |
11 | #include <linux/i2c.h> | |
12 | #include <linux/rtc.h> | |
13 | ||
14 | #define DRV_VERSION "0.2" | |
15 | ||
16 | /* Addresses to scan: none. This chip cannot be detected. */ | |
17 | static unsigned short normal_i2c[] = { I2C_CLIENT_END }; | |
18 | ||
19 | /* Insmod parameters */ | |
20 | I2C_CLIENT_INSMOD; | |
21 | ||
22 | /* Registers */ | |
23 | ||
24 | #define DS1672_REG_CNT_BASE 0 | |
25 | #define DS1672_REG_CONTROL 4 | |
26 | #define DS1672_REG_TRICKLE 5 | |
27 | ||
28 | ||
29 | /* Prototypes */ | |
30 | static int ds1672_probe(struct i2c_adapter *adapter, int address, int kind); | |
31 | ||
32 | /* | |
33 | * In the routines that deal directly with the ds1672 hardware, we use | |
34 | * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch | |
35 | * Epoch is initialized as 2000. Time is set to UTC. | |
36 | */ | |
37 | static int ds1672_get_datetime(struct i2c_client *client, struct rtc_time *tm) | |
38 | { | |
39 | unsigned long time; | |
40 | unsigned char addr = DS1672_REG_CNT_BASE; | |
41 | unsigned char buf[4]; | |
42 | ||
43 | struct i2c_msg msgs[] = { | |
44 | { client->addr, 0, 1, &addr }, /* setup read ptr */ | |
45 | { client->addr, I2C_M_RD, 4, buf }, /* read date */ | |
46 | }; | |
47 | ||
48 | /* read date registers */ | |
49 | if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) { | |
50 | dev_err(&client->dev, "%s: read error\n", __FUNCTION__); | |
51 | return -EIO; | |
52 | } | |
53 | ||
54 | dev_dbg(&client->dev, | |
55 | "%s: raw read data - counters=%02x,%02x,%02x,%02x\n" | |
56 | __FUNCTION__, | |
57 | buf[0], buf[1], buf[2], buf[3]); | |
58 | ||
59 | time = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0]; | |
60 | ||
61 | rtc_time_to_tm(time, tm); | |
62 | ||
63 | dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, " | |
64 | "mday=%d, mon=%d, year=%d, wday=%d\n", | |
65 | __FUNCTION__, | |
66 | tm->tm_sec, tm->tm_min, tm->tm_hour, | |
67 | tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); | |
68 | ||
69 | return 0; | |
70 | } | |
71 | ||
72 | static int ds1672_set_mmss(struct i2c_client *client, unsigned long secs) | |
73 | { | |
74 | int xfer; | |
75 | unsigned char buf[5]; | |
76 | ||
77 | buf[0] = DS1672_REG_CNT_BASE; | |
78 | buf[1] = secs & 0x000000FF; | |
79 | buf[2] = (secs & 0x0000FF00) >> 8; | |
80 | buf[3] = (secs & 0x00FF0000) >> 16; | |
81 | buf[4] = (secs & 0xFF000000) >> 24; | |
82 | ||
83 | xfer = i2c_master_send(client, buf, 5); | |
84 | if (xfer != 5) { | |
85 | dev_err(&client->dev, "%s: send: %d\n", __FUNCTION__, xfer); | |
86 | return -EIO; | |
87 | } | |
88 | ||
89 | return 0; | |
90 | } | |
91 | ||
92 | static int ds1672_set_datetime(struct i2c_client *client, struct rtc_time *tm) | |
93 | { | |
94 | unsigned long secs; | |
95 | ||
96 | dev_dbg(&client->dev, | |
97 | "%s: secs=%d, mins=%d, hours=%d, ", | |
98 | "mday=%d, mon=%d, year=%d, wday=%d\n", | |
99 | __FUNCTION__, | |
100 | tm->tm_sec, tm->tm_min, tm->tm_hour, | |
101 | tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); | |
102 | ||
103 | rtc_tm_to_time(tm, &secs); | |
104 | ||
105 | return ds1672_set_mmss(client, secs); | |
106 | } | |
107 | ||
108 | static int ds1672_rtc_read_time(struct device *dev, struct rtc_time *tm) | |
109 | { | |
110 | return ds1672_get_datetime(to_i2c_client(dev), tm); | |
111 | } | |
112 | ||
113 | static int ds1672_rtc_set_time(struct device *dev, struct rtc_time *tm) | |
114 | { | |
115 | return ds1672_set_datetime(to_i2c_client(dev), tm); | |
116 | } | |
117 | ||
118 | static int ds1672_rtc_set_mmss(struct device *dev, unsigned long secs) | |
119 | { | |
120 | return ds1672_set_mmss(to_i2c_client(dev), secs); | |
121 | } | |
122 | ||
123 | static struct rtc_class_ops ds1672_rtc_ops = { | |
124 | .read_time = ds1672_rtc_read_time, | |
125 | .set_time = ds1672_rtc_set_time, | |
126 | .set_mmss = ds1672_rtc_set_mmss, | |
127 | }; | |
128 | ||
129 | static int ds1672_attach(struct i2c_adapter *adapter) | |
130 | { | |
131 | dev_dbg(&adapter->dev, "%s\n", __FUNCTION__); | |
132 | return i2c_probe(adapter, &addr_data, ds1672_probe); | |
133 | } | |
134 | ||
135 | static int ds1672_detach(struct i2c_client *client) | |
136 | { | |
137 | int err; | |
138 | struct rtc_device *rtc = i2c_get_clientdata(client); | |
139 | ||
140 | dev_dbg(&client->dev, "%s\n", __FUNCTION__); | |
141 | ||
142 | if (rtc) | |
143 | rtc_device_unregister(rtc); | |
144 | ||
145 | if ((err = i2c_detach_client(client))) | |
146 | return err; | |
147 | ||
148 | kfree(client); | |
149 | ||
150 | return 0; | |
151 | } | |
152 | ||
153 | static struct i2c_driver ds1672_driver = { | |
154 | .driver = { | |
155 | .name = "ds1672", | |
156 | }, | |
157 | .id = I2C_DRIVERID_DS1672, | |
158 | .attach_adapter = &ds1672_attach, | |
159 | .detach_client = &ds1672_detach, | |
160 | }; | |
161 | ||
162 | static int ds1672_probe(struct i2c_adapter *adapter, int address, int kind) | |
163 | { | |
164 | int err = 0; | |
165 | struct i2c_client *client; | |
166 | struct rtc_device *rtc; | |
167 | ||
168 | dev_dbg(&adapter->dev, "%s\n", __FUNCTION__); | |
169 | ||
170 | if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) { | |
171 | err = -ENODEV; | |
172 | goto exit; | |
173 | } | |
174 | ||
175 | if (!(client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL))) { | |
176 | err = -ENOMEM; | |
177 | goto exit; | |
178 | } | |
179 | ||
180 | /* I2C client */ | |
181 | client->addr = address; | |
182 | client->driver = &ds1672_driver; | |
183 | client->adapter = adapter; | |
184 | ||
185 | strlcpy(client->name, ds1672_driver.driver.name, I2C_NAME_SIZE); | |
186 | ||
187 | /* Inform the i2c layer */ | |
188 | if ((err = i2c_attach_client(client))) | |
189 | goto exit_kfree; | |
190 | ||
191 | dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); | |
192 | ||
193 | rtc = rtc_device_register(ds1672_driver.driver.name, &client->dev, | |
194 | &ds1672_rtc_ops, THIS_MODULE); | |
195 | ||
196 | if (IS_ERR(rtc)) { | |
197 | err = PTR_ERR(rtc); | |
198 | dev_err(&client->dev, | |
199 | "unable to register the class device\n"); | |
200 | goto exit_detach; | |
201 | } | |
202 | ||
203 | i2c_set_clientdata(client, rtc); | |
204 | ||
205 | return 0; | |
206 | ||
207 | exit_detach: | |
208 | i2c_detach_client(client); | |
209 | ||
210 | exit_kfree: | |
211 | kfree(client); | |
212 | ||
213 | exit: | |
214 | return err; | |
215 | } | |
216 | ||
217 | static int __init ds1672_init(void) | |
218 | { | |
219 | return i2c_add_driver(&ds1672_driver); | |
220 | } | |
221 | ||
222 | static void __exit ds1672_exit(void) | |
223 | { | |
224 | i2c_del_driver(&ds1672_driver); | |
225 | } | |
226 | ||
227 | MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); | |
228 | MODULE_DESCRIPTION("Dallas/Maxim DS1672 timekeeper driver"); | |
229 | MODULE_LICENSE("GPL"); | |
230 | MODULE_VERSION(DRV_VERSION); | |
231 | ||
232 | module_init(ds1672_init); | |
233 | module_exit(ds1672_exit); |