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authorAlessandro Zummo <a.zummo@towertech.it>2006-03-27 04:16:43 -0500
committerLinus Torvalds <torvalds@g5.osdl.org>2006-03-27 11:44:52 -0500
commitedf1aaa31fc52ade0da7b6d1f2dffc17f0bdb9ff (patch)
tree2bd1729cc36c40678dff7f7d422c7354be89edbc /drivers/rtc
parenta95579cd4b40a4e062e187d931f498145551ee29 (diff)
[PATCH] RTC subsystem: DS1672 driver
Driver for the Dallas/Maxim DS1672 chip, found on the Loft (http://www.giantshoulderinc.com). Signed-off-by: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/rtc')
-rw-r--r--drivers/rtc/Kconfig10
-rw-r--r--drivers/rtc/Makefile1
-rw-r--r--drivers/rtc/rtc-ds1672.c233
3 files changed, 244 insertions, 0 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 7eb1368d04f6..de3352658654 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -86,6 +86,16 @@ config RTC_DRV_X1205
86 This driver can also be built as a module. If so, the module 86 This driver can also be built as a module. If so, the module
87 will be called rtc-x1205. 87 will be called rtc-x1205.
88 88
89config RTC_DRV_DS1672
90 tristate "Dallas/Maxim DS1672"
91 depends on RTC_CLASS && I2C
92 help
93 If you say yes here you get support for the
94 Dallas/Maxim DS1672 timekeeping chip.
95
96 This driver can also be built as a module. If so, the module
97 will be called rtc-ds1672.
98
89config RTC_DRV_TEST 99config RTC_DRV_TEST
90 tristate "Test driver/device" 100 tristate "Test driver/device"
91 depends on RTC_CLASS 101 depends on RTC_CLASS
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index d5ea0ed81905..f3fd5b0cd735 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -13,4 +13,5 @@ obj-$(CONFIG_RTC_INTF_DEV) += rtc-dev.o
13 13
14obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o 14obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o
15obj-$(CONFIG_RTC_DRV_TEST) += rtc-test.o 15obj-$(CONFIG_RTC_DRV_TEST) += rtc-test.o
16obj-$(CONFIG_RTC_DRV_DS1672) += rtc-ds1672.o
16 17
diff --git a/drivers/rtc/rtc-ds1672.c b/drivers/rtc/rtc-ds1672.c
new file mode 100644
index 000000000000..358695a416f3
--- /dev/null
+++ b/drivers/rtc/rtc-ds1672.c
@@ -0,0 +1,233 @@
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. */
17static unsigned short normal_i2c[] = { I2C_CLIENT_END };
18
19/* Insmod parameters */
20I2C_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 */
30static 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 */
37static 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
72static 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
92static 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
108static 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
113static 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
118static int ds1672_rtc_set_mmss(struct device *dev, unsigned long secs)
119{
120 return ds1672_set_mmss(to_i2c_client(dev), secs);
121}
122
123static 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
129static 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
135static 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
153static 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
162static 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
207exit_detach:
208 i2c_detach_client(client);
209
210exit_kfree:
211 kfree(client);
212
213exit:
214 return err;
215}
216
217static int __init ds1672_init(void)
218{
219 return i2c_add_driver(&ds1672_driver);
220}
221
222static void __exit ds1672_exit(void)
223{
224 i2c_del_driver(&ds1672_driver);
225}
226
227MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
228MODULE_DESCRIPTION("Dallas/Maxim DS1672 timekeeper driver");
229MODULE_LICENSE("GPL");
230MODULE_VERSION(DRV_VERSION);
231
232module_init(ds1672_init);
233module_exit(ds1672_exit);