]>
Commit | Line | Data |
---|---|---|
1d98af87 AZ |
1 | /* |
2 | * ST M48T86 / Dallas DS12887 RTC driver | |
3 | * Copyright (c) 2006 Tower Technologies | |
4 | * | |
5 | * Author: Alessandro Zummo <a.zummo@towertech.it> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | * | |
11 | * This drivers only supports the clock running in BCD and 24H mode. | |
12 | * If it will be ever adapted to binary and 12H mode, care must be taken | |
13 | * to not introduce bugs. | |
14 | */ | |
15 | ||
16 | #include <linux/module.h> | |
17 | #include <linux/rtc.h> | |
18 | #include <linux/platform_device.h> | |
803bb301 | 19 | #include <linux/platform_data/rtc-m48t86.h> |
1d98af87 AZ |
20 | #include <linux/bcd.h> |
21 | ||
68b54f47 HS |
22 | #define M48T86_SEC 0x00 |
23 | #define M48T86_SECALRM 0x01 | |
24 | #define M48T86_MIN 0x02 | |
25 | #define M48T86_MINALRM 0x03 | |
26 | #define M48T86_HOUR 0x04 | |
27 | #define M48T86_HOURALRM 0x05 | |
28 | #define M48T86_DOW 0x06 /* 1 = sunday */ | |
29 | #define M48T86_DOM 0x07 | |
30 | #define M48T86_MONTH 0x08 /* 1 - 12 */ | |
31 | #define M48T86_YEAR 0x09 /* 0 - 99 */ | |
32 | #define M48T86_A 0x0a | |
33 | #define M48T86_B 0x0b | |
34 | #define M48T86_B_SET BIT(7) | |
35 | #define M48T86_B_DM BIT(2) | |
36 | #define M48T86_B_H24 BIT(1) | |
37 | #define M48T86_C 0x0c | |
38 | #define M48T86_D 0x0d | |
39 | #define M48T86_D_VRT BIT(7) | |
1d98af87 | 40 | |
1d98af87 AZ |
41 | static int m48t86_rtc_read_time(struct device *dev, struct rtc_time *tm) |
42 | { | |
43 | unsigned char reg; | |
44 | struct platform_device *pdev = to_platform_device(dev); | |
b5f0902d | 45 | struct m48t86_ops *ops = dev_get_platdata(&pdev->dev); |
1d98af87 | 46 | |
68b54f47 | 47 | reg = ops->readbyte(M48T86_B); |
1d98af87 | 48 | |
68b54f47 | 49 | if (reg & M48T86_B_DM) { |
1d98af87 | 50 | /* data (binary) mode */ |
68b54f47 HS |
51 | tm->tm_sec = ops->readbyte(M48T86_SEC); |
52 | tm->tm_min = ops->readbyte(M48T86_MIN); | |
53 | tm->tm_hour = ops->readbyte(M48T86_HOUR) & 0x3f; | |
54 | tm->tm_mday = ops->readbyte(M48T86_DOM); | |
1d98af87 | 55 | /* tm_mon is 0-11 */ |
68b54f47 HS |
56 | tm->tm_mon = ops->readbyte(M48T86_MONTH) - 1; |
57 | tm->tm_year = ops->readbyte(M48T86_YEAR) + 100; | |
58 | tm->tm_wday = ops->readbyte(M48T86_DOW); | |
1d98af87 AZ |
59 | } else { |
60 | /* bcd mode */ | |
68b54f47 HS |
61 | tm->tm_sec = bcd2bin(ops->readbyte(M48T86_SEC)); |
62 | tm->tm_min = bcd2bin(ops->readbyte(M48T86_MIN)); | |
63 | tm->tm_hour = bcd2bin(ops->readbyte(M48T86_HOUR) & 0x3f); | |
64 | tm->tm_mday = bcd2bin(ops->readbyte(M48T86_DOM)); | |
1d98af87 | 65 | /* tm_mon is 0-11 */ |
68b54f47 HS |
66 | tm->tm_mon = bcd2bin(ops->readbyte(M48T86_MONTH)) - 1; |
67 | tm->tm_year = bcd2bin(ops->readbyte(M48T86_YEAR)) + 100; | |
68 | tm->tm_wday = bcd2bin(ops->readbyte(M48T86_DOW)); | |
1d98af87 AZ |
69 | } |
70 | ||
71 | /* correct the hour if the clock is in 12h mode */ | |
68b54f47 HS |
72 | if (!(reg & M48T86_B_H24)) |
73 | if (ops->readbyte(M48T86_HOUR) & 0x80) | |
1d98af87 AZ |
74 | tm->tm_hour += 12; |
75 | ||
52142ed4 | 76 | return rtc_valid_tm(tm); |
1d98af87 AZ |
77 | } |
78 | ||
79 | static int m48t86_rtc_set_time(struct device *dev, struct rtc_time *tm) | |
80 | { | |
81 | unsigned char reg; | |
82 | struct platform_device *pdev = to_platform_device(dev); | |
b5f0902d | 83 | struct m48t86_ops *ops = dev_get_platdata(&pdev->dev); |
1d98af87 | 84 | |
68b54f47 | 85 | reg = ops->readbyte(M48T86_B); |
1d98af87 AZ |
86 | |
87 | /* update flag and 24h mode */ | |
68b54f47 HS |
88 | reg |= M48T86_B_SET | M48T86_B_H24; |
89 | ops->writebyte(reg, M48T86_B); | |
1d98af87 | 90 | |
68b54f47 | 91 | if (reg & M48T86_B_DM) { |
1d98af87 | 92 | /* data (binary) mode */ |
68b54f47 HS |
93 | ops->writebyte(tm->tm_sec, M48T86_SEC); |
94 | ops->writebyte(tm->tm_min, M48T86_MIN); | |
95 | ops->writebyte(tm->tm_hour, M48T86_HOUR); | |
96 | ops->writebyte(tm->tm_mday, M48T86_DOM); | |
97 | ops->writebyte(tm->tm_mon + 1, M48T86_MONTH); | |
98 | ops->writebyte(tm->tm_year % 100, M48T86_YEAR); | |
99 | ops->writebyte(tm->tm_wday, M48T86_DOW); | |
1d98af87 AZ |
100 | } else { |
101 | /* bcd mode */ | |
68b54f47 HS |
102 | ops->writebyte(bin2bcd(tm->tm_sec), M48T86_SEC); |
103 | ops->writebyte(bin2bcd(tm->tm_min), M48T86_MIN); | |
104 | ops->writebyte(bin2bcd(tm->tm_hour), M48T86_HOUR); | |
105 | ops->writebyte(bin2bcd(tm->tm_mday), M48T86_DOM); | |
106 | ops->writebyte(bin2bcd(tm->tm_mon + 1), M48T86_MONTH); | |
107 | ops->writebyte(bin2bcd(tm->tm_year % 100), M48T86_YEAR); | |
108 | ops->writebyte(bin2bcd(tm->tm_wday), M48T86_DOW); | |
1d98af87 AZ |
109 | } |
110 | ||
111 | /* update ended */ | |
68b54f47 HS |
112 | reg &= ~M48T86_B_SET; |
113 | ops->writebyte(reg, M48T86_B); | |
1d98af87 AZ |
114 | |
115 | return 0; | |
116 | } | |
117 | ||
118 | static int m48t86_rtc_proc(struct device *dev, struct seq_file *seq) | |
119 | { | |
120 | unsigned char reg; | |
121 | struct platform_device *pdev = to_platform_device(dev); | |
b5f0902d | 122 | struct m48t86_ops *ops = dev_get_platdata(&pdev->dev); |
1d98af87 | 123 | |
68b54f47 | 124 | reg = ops->readbyte(M48T86_B); |
1d98af87 | 125 | |
1d98af87 | 126 | seq_printf(seq, "mode\t\t: %s\n", |
68b54f47 | 127 | (reg & M48T86_B_DM) ? "binary" : "bcd"); |
1d98af87 | 128 | |
68b54f47 | 129 | reg = ops->readbyte(M48T86_D); |
1d98af87 AZ |
130 | |
131 | seq_printf(seq, "battery\t\t: %s\n", | |
68b54f47 | 132 | (reg & M48T86_D_VRT) ? "ok" : "exhausted"); |
1d98af87 AZ |
133 | |
134 | return 0; | |
135 | } | |
136 | ||
ff8371ac | 137 | static const struct rtc_class_ops m48t86_rtc_ops = { |
1d98af87 AZ |
138 | .read_time = m48t86_rtc_read_time, |
139 | .set_time = m48t86_rtc_set_time, | |
140 | .proc = m48t86_rtc_proc, | |
141 | }; | |
142 | ||
5a167f45 | 143 | static int m48t86_rtc_probe(struct platform_device *dev) |
1d98af87 AZ |
144 | { |
145 | unsigned char reg; | |
b5f0902d | 146 | struct m48t86_ops *ops = dev_get_platdata(&dev->dev); |
d5b6bb0a JH |
147 | struct rtc_device *rtc; |
148 | ||
149 | rtc = devm_rtc_device_register(&dev->dev, "m48t86", | |
68b54f47 | 150 | &m48t86_rtc_ops, THIS_MODULE); |
1d98af87 | 151 | |
d1d65b77 | 152 | if (IS_ERR(rtc)) |
1d98af87 | 153 | return PTR_ERR(rtc); |
1d98af87 AZ |
154 | |
155 | platform_set_drvdata(dev, rtc); | |
156 | ||
157 | /* read battery status */ | |
68b54f47 | 158 | reg = ops->readbyte(M48T86_D); |
1d98af87 | 159 | dev_info(&dev->dev, "battery %s\n", |
68b54f47 | 160 | (reg & M48T86_D_VRT) ? "ok" : "exhausted"); |
1d98af87 AZ |
161 | |
162 | return 0; | |
163 | } | |
164 | ||
1d98af87 AZ |
165 | static struct platform_driver m48t86_rtc_platform_driver = { |
166 | .driver = { | |
167 | .name = "rtc-m48t86", | |
1d98af87 AZ |
168 | }, |
169 | .probe = m48t86_rtc_probe, | |
1d98af87 AZ |
170 | }; |
171 | ||
0c4eae66 | 172 | module_platform_driver(m48t86_rtc_platform_driver); |
1d98af87 AZ |
173 | |
174 | MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); | |
175 | MODULE_DESCRIPTION("M48T86 RTC driver"); | |
176 | MODULE_LICENSE("GPL"); | |
ad28a07b | 177 | MODULE_ALIAS("platform:rtc-m48t86"); |