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5
6
7#define RTC_VERSION "1.00"
8
9#include <linux/types.h>
10#include <linux/errno.h>
11#include <linux/miscdevice.h>
12#include <linux/ioport.h>
13#include <linux/capability.h>
14#include <linux/fcntl.h>
15#include <linux/init.h>
16#include <linux/poll.h>
17#include <linux/module.h>
18#include <linux/mc146818rtc.h>
19#include <linux/bcd.h>
20#include <asm/bvme6000hw.h>
21
22#include <asm/io.h>
23#include <asm/uaccess.h>
24#include <asm/setup.h>
25
26
27
28
29
30
31
32
33static unsigned char days_in_mo[] =
34{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
35
36static atomic_t rtc_status = ATOMIC_INIT(1);
37
38static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
39{
40 volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
41 unsigned char msr;
42 unsigned long flags;
43 struct rtc_time wtime;
44 void __user *argp = (void __user *)arg;
45
46 switch (cmd) {
47 case RTC_RD_TIME:
48 {
49 local_irq_save(flags);
50
51 msr = rtc->msr & 0xc0;
52 rtc->msr = 0x40;
53 memset(&wtime, 0, sizeof(struct rtc_time));
54 do {
55 wtime.tm_sec = bcd2bin(rtc->bcd_sec);
56 wtime.tm_min = bcd2bin(rtc->bcd_min);
57 wtime.tm_hour = bcd2bin(rtc->bcd_hr);
58 wtime.tm_mday = bcd2bin(rtc->bcd_dom);
59 wtime.tm_mon = bcd2bin(rtc->bcd_mth)-1;
60 wtime.tm_year = bcd2bin(rtc->bcd_year);
61 if (wtime.tm_year < 70)
62 wtime.tm_year += 100;
63 wtime.tm_wday = bcd2bin(rtc->bcd_dow)-1;
64 } while (wtime.tm_sec != bcd2bin(rtc->bcd_sec));
65 rtc->msr = msr;
66 local_irq_restore(flags);
67 return copy_to_user(argp, &wtime, sizeof wtime) ?
68 -EFAULT : 0;
69 }
70 case RTC_SET_TIME:
71 {
72 struct rtc_time rtc_tm;
73 unsigned char mon, day, hrs, min, sec, leap_yr;
74 unsigned int yrs;
75
76 if (!capable(CAP_SYS_ADMIN))
77 return -EACCES;
78
79 if (copy_from_user(&rtc_tm, argp, sizeof(struct rtc_time)))
80 return -EFAULT;
81
82 yrs = rtc_tm.tm_year;
83 if (yrs < 1900)
84 yrs += 1900;
85 mon = rtc_tm.tm_mon + 1;
86 day = rtc_tm.tm_mday;
87 hrs = rtc_tm.tm_hour;
88 min = rtc_tm.tm_min;
89 sec = rtc_tm.tm_sec;
90
91 leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
92
93 if ((mon > 12) || (mon < 1) || (day == 0))
94 return -EINVAL;
95
96 if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
97 return -EINVAL;
98
99 if ((hrs >= 24) || (min >= 60) || (sec >= 60))
100 return -EINVAL;
101
102 if (yrs >= 2070)
103 return -EINVAL;
104
105 local_irq_save(flags);
106
107 msr = rtc->msr & 0xc0;
108 rtc->msr = 0x40;
109
110 rtc->t0cr_rtmr = yrs%4;
111 rtc->bcd_tenms = 0;
112 rtc->bcd_sec = bin2bcd(sec);
113 rtc->bcd_min = bin2bcd(min);
114 rtc->bcd_hr = bin2bcd(hrs);
115 rtc->bcd_dom = bin2bcd(day);
116 rtc->bcd_mth = bin2bcd(mon);
117 rtc->bcd_year = bin2bcd(yrs%100);
118 if (rtc_tm.tm_wday >= 0)
119 rtc->bcd_dow = bin2bcd(rtc_tm.tm_wday+1);
120 rtc->t0cr_rtmr = yrs%4 | 0x08;
121
122 rtc->msr = msr;
123 local_irq_restore(flags);
124 return 0;
125 }
126 default:
127 return -EINVAL;
128 }
129}
130
131
132
133
134static int rtc_open(struct inode *inode, struct file *file)
135{
136 if (!atomic_dec_and_test(&rtc_status)) {
137 atomic_inc(&rtc_status);
138 return -EBUSY;
139 }
140 return 0;
141}
142
143static int rtc_release(struct inode *inode, struct file *file)
144{
145 atomic_inc(&rtc_status);
146 return 0;
147}
148
149
150
151
152
153static const struct file_operations rtc_fops = {
154 .unlocked_ioctl = rtc_ioctl,
155 .open = rtc_open,
156 .release = rtc_release,
157 .llseek = noop_llseek,
158};
159
160static struct miscdevice rtc_dev = {
161 .minor = RTC_MINOR,
162 .name = "rtc",
163 .fops = &rtc_fops
164};
165
166static int __init rtc_DP8570A_init(void)
167{
168 if (!MACH_IS_BVME6000)
169 return -ENODEV;
170
171 printk(KERN_INFO "DP8570A Real Time Clock Driver v%s\n", RTC_VERSION);
172 return misc_register(&rtc_dev);
173}
174module_init(rtc_DP8570A_init);
175