]>
Commit | Line | Data |
---|---|---|
739d340d PM |
1 | /* |
2 | * Dallas DS1302 RTC Support | |
3 | * | |
2bfc3305 AZ |
4 | * Copyright (C) 2002 David McCullough |
5 | * Copyright (C) 2003 - 2007 Paul Mundt | |
739d340d PM |
6 | * |
7 | * This file is subject to the terms and conditions of the GNU General Public | |
2bfc3305 | 8 | * License version 2. See the file "COPYING" in the main directory of |
739d340d PM |
9 | * this archive for more details. |
10 | */ | |
2bfc3305 | 11 | |
739d340d PM |
12 | #include <linux/init.h> |
13 | #include <linux/module.h> | |
14 | #include <linux/kernel.h> | |
15 | #include <linux/platform_device.h> | |
739d340d | 16 | #include <linux/rtc.h> |
739d340d PM |
17 | #include <linux/io.h> |
18 | #include <linux/bcd.h> | |
19 | #include <asm/rtc.h> | |
20 | ||
21 | #define DRV_NAME "rtc-ds1302" | |
2bfc3305 | 22 | #define DRV_VERSION "0.1.1" |
739d340d PM |
23 | |
24 | #define RTC_CMD_READ 0x81 /* Read command */ | |
25 | #define RTC_CMD_WRITE 0x80 /* Write command */ | |
26 | ||
27 | #define RTC_ADDR_RAM0 0x20 /* Address of RAM0 */ | |
28 | #define RTC_ADDR_TCR 0x08 /* Address of trickle charge register */ | |
29 | #define RTC_ADDR_YEAR 0x06 /* Address of year register */ | |
30 | #define RTC_ADDR_DAY 0x05 /* Address of day of week register */ | |
31 | #define RTC_ADDR_MON 0x04 /* Address of month register */ | |
32 | #define RTC_ADDR_DATE 0x03 /* Address of day of month register */ | |
33 | #define RTC_ADDR_HOUR 0x02 /* Address of hour register */ | |
34 | #define RTC_ADDR_MIN 0x01 /* Address of minute register */ | |
35 | #define RTC_ADDR_SEC 0x00 /* Address of second register */ | |
36 | ||
37 | #define RTC_RESET 0x1000 | |
38 | #define RTC_IODATA 0x0800 | |
39 | #define RTC_SCLK 0x0400 | |
40 | ||
41 | #ifdef CONFIG_SH_SECUREEDGE5410 | |
7639a454 | 42 | #include <mach/snapgear.h> |
739d340d PM |
43 | #define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00) |
44 | #define get_dp() SECUREEDGE_READ_IOPORT() | |
45 | #else | |
46 | #error "Add support for your platform" | |
47 | #endif | |
48 | ||
739d340d PM |
49 | static void ds1302_sendbits(unsigned int val) |
50 | { | |
51 | int i; | |
52 | ||
53 | for (i = 8; (i); i--, val >>= 1) { | |
54 | set_dp((get_dp() & ~RTC_IODATA) | ((val & 0x1) ? | |
55 | RTC_IODATA : 0)); | |
56 | set_dp(get_dp() | RTC_SCLK); /* clock high */ | |
57 | set_dp(get_dp() & ~RTC_SCLK); /* clock low */ | |
58 | } | |
59 | } | |
60 | ||
61 | static unsigned int ds1302_recvbits(void) | |
62 | { | |
63 | unsigned int val; | |
64 | int i; | |
65 | ||
66 | for (i = 0, val = 0; (i < 8); i++) { | |
67 | val |= (((get_dp() & RTC_IODATA) ? 1 : 0) << i); | |
68 | set_dp(get_dp() | RTC_SCLK); /* clock high */ | |
69 | set_dp(get_dp() & ~RTC_SCLK); /* clock low */ | |
70 | } | |
71 | ||
72 | return val; | |
73 | } | |
74 | ||
75 | static unsigned int ds1302_readbyte(unsigned int addr) | |
76 | { | |
77 | unsigned int val; | |
78 | ||
79 | set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK)); | |
80 | ||
81 | set_dp(get_dp() | RTC_RESET); | |
82 | ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_READ); | |
83 | val = ds1302_recvbits(); | |
84 | set_dp(get_dp() & ~RTC_RESET); | |
85 | ||
86 | return val; | |
87 | } | |
88 | ||
89 | static void ds1302_writebyte(unsigned int addr, unsigned int val) | |
90 | { | |
91 | set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK)); | |
92 | set_dp(get_dp() | RTC_RESET); | |
93 | ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_WRITE); | |
94 | ds1302_sendbits(val); | |
95 | set_dp(get_dp() & ~RTC_RESET); | |
96 | } | |
97 | ||
98 | static int ds1302_rtc_read_time(struct device *dev, struct rtc_time *tm) | |
99 | { | |
fe20ba70 AB |
100 | tm->tm_sec = bcd2bin(ds1302_readbyte(RTC_ADDR_SEC)); |
101 | tm->tm_min = bcd2bin(ds1302_readbyte(RTC_ADDR_MIN)); | |
102 | tm->tm_hour = bcd2bin(ds1302_readbyte(RTC_ADDR_HOUR)); | |
103 | tm->tm_wday = bcd2bin(ds1302_readbyte(RTC_ADDR_DAY)); | |
104 | tm->tm_mday = bcd2bin(ds1302_readbyte(RTC_ADDR_DATE)); | |
105 | tm->tm_mon = bcd2bin(ds1302_readbyte(RTC_ADDR_MON)) - 1; | |
106 | tm->tm_year = bcd2bin(ds1302_readbyte(RTC_ADDR_YEAR)); | |
739d340d PM |
107 | |
108 | if (tm->tm_year < 70) | |
109 | tm->tm_year += 100; | |
110 | ||
739d340d PM |
111 | dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, " |
112 | "mday=%d, mon=%d, year=%d, wday=%d\n", | |
2a4e2b87 | 113 | __func__, |
739d340d PM |
114 | tm->tm_sec, tm->tm_min, tm->tm_hour, |
115 | tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday); | |
116 | ||
2bfc3305 | 117 | return rtc_valid_tm(tm); |
739d340d PM |
118 | } |
119 | ||
120 | static int ds1302_rtc_set_time(struct device *dev, struct rtc_time *tm) | |
121 | { | |
739d340d PM |
122 | /* Stop RTC */ |
123 | ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) | 0x80); | |
124 | ||
fe20ba70 AB |
125 | ds1302_writebyte(RTC_ADDR_SEC, bin2bcd(tm->tm_sec)); |
126 | ds1302_writebyte(RTC_ADDR_MIN, bin2bcd(tm->tm_min)); | |
127 | ds1302_writebyte(RTC_ADDR_HOUR, bin2bcd(tm->tm_hour)); | |
128 | ds1302_writebyte(RTC_ADDR_DAY, bin2bcd(tm->tm_wday)); | |
129 | ds1302_writebyte(RTC_ADDR_DATE, bin2bcd(tm->tm_mday)); | |
130 | ds1302_writebyte(RTC_ADDR_MON, bin2bcd(tm->tm_mon + 1)); | |
131 | ds1302_writebyte(RTC_ADDR_YEAR, bin2bcd(tm->tm_year % 100)); | |
739d340d PM |
132 | |
133 | /* Start RTC */ | |
134 | ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) & ~0x80); | |
135 | ||
739d340d PM |
136 | return 0; |
137 | } | |
138 | ||
139 | static int ds1302_rtc_ioctl(struct device *dev, unsigned int cmd, | |
140 | unsigned long arg) | |
141 | { | |
142 | switch (cmd) { | |
143 | #ifdef RTC_SET_CHARGE | |
144 | case RTC_SET_CHARGE: | |
145 | { | |
739d340d PM |
146 | int tcs_val; |
147 | ||
148 | if (copy_from_user(&tcs_val, (int __user *)arg, sizeof(int))) | |
149 | return -EFAULT; | |
150 | ||
739d340d | 151 | ds1302_writebyte(RTC_ADDR_TCR, (0xa0 | tcs_val * 0xf)); |
739d340d PM |
152 | return 0; |
153 | } | |
154 | #endif | |
155 | } | |
156 | ||
157 | return -ENOIOCTLCMD; | |
158 | } | |
159 | ||
160 | static struct rtc_class_ops ds1302_rtc_ops = { | |
161 | .read_time = ds1302_rtc_read_time, | |
162 | .set_time = ds1302_rtc_set_time, | |
163 | .ioctl = ds1302_rtc_ioctl, | |
164 | }; | |
165 | ||
2bfc3305 | 166 | static int __init ds1302_rtc_probe(struct platform_device *pdev) |
739d340d | 167 | { |
2bfc3305 | 168 | struct rtc_device *rtc; |
739d340d PM |
169 | |
170 | /* Reset */ | |
171 | set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK)); | |
172 | ||
173 | /* Write a magic value to the DS1302 RAM, and see if it sticks. */ | |
174 | ds1302_writebyte(RTC_ADDR_RAM0, 0x42); | |
175 | if (ds1302_readbyte(RTC_ADDR_RAM0) != 0x42) | |
176 | return -ENODEV; | |
177 | ||
2bfc3305 | 178 | rtc = rtc_device_register("ds1302", &pdev->dev, |
739d340d | 179 | &ds1302_rtc_ops, THIS_MODULE); |
2bfc3305 AZ |
180 | if (IS_ERR(rtc)) |
181 | return PTR_ERR(rtc); | |
739d340d PM |
182 | |
183 | platform_set_drvdata(pdev, rtc); | |
184 | ||
185 | return 0; | |
739d340d PM |
186 | } |
187 | ||
188 | static int __devexit ds1302_rtc_remove(struct platform_device *pdev) | |
189 | { | |
2bfc3305 | 190 | struct rtc_device *rtc = platform_get_drvdata(pdev); |
739d340d | 191 | |
2bfc3305 | 192 | rtc_device_unregister(rtc); |
739d340d PM |
193 | platform_set_drvdata(pdev, NULL); |
194 | ||
739d340d PM |
195 | return 0; |
196 | } | |
197 | ||
198 | static struct platform_driver ds1302_platform_driver = { | |
199 | .driver = { | |
200 | .name = DRV_NAME, | |
201 | .owner = THIS_MODULE, | |
202 | }, | |
b9e05c64 | 203 | .remove = __devexit_p(ds1302_rtc_remove), |
739d340d PM |
204 | }; |
205 | ||
206 | static int __init ds1302_rtc_init(void) | |
207 | { | |
2bfc3305 | 208 | return platform_driver_probe(&ds1302_platform_driver, ds1302_rtc_probe); |
739d340d PM |
209 | } |
210 | ||
211 | static void __exit ds1302_rtc_exit(void) | |
212 | { | |
213 | platform_driver_unregister(&ds1302_platform_driver); | |
214 | } | |
215 | ||
216 | module_init(ds1302_rtc_init); | |
217 | module_exit(ds1302_rtc_exit); | |
218 | ||
219 | MODULE_DESCRIPTION("Dallas DS1302 RTC driver"); | |
220 | MODULE_VERSION(DRV_VERSION); | |
221 | MODULE_AUTHOR("Paul Mundt, David McCullough"); | |
222 | MODULE_LICENSE("GPL v2"); |