blob: f7573f2bcb9c5b356a51aa25a7fc028be1bc8462 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Real Time Clock interface for Linux on the BVME6000
3 *
4 * Based on the PC driver by Paul Gortmaker.
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/slab.h>
13#include <linux/ioport.h>
Randy Dunlapa9415642006-01-11 12:17:48 -080014#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/fcntl.h>
16#include <linux/init.h>
17#include <linux/poll.h>
Christoph Hellwig573fc112005-09-06 15:16:58 -070018#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/mc146818rtc.h> /* For struct rtc_time and ioctls, etc */
20#include <linux/smp_lock.h>
21#include <asm/bvme6000hw.h>
22
23#include <asm/io.h>
24#include <asm/uaccess.h>
25#include <asm/system.h>
26#include <asm/setup.h>
27
28/*
29 * We sponge a minor off of the misc major. No need slurping
30 * up another valuable major dev number for this. If you add
31 * an ioctl, make sure you don't conflict with SPARC's RTC
32 * ioctls.
33 */
34
35#define BCD2BIN(val) (((val)&15) + ((val)>>4)*10)
36#define BIN2BCD(val) ((((val)/10)<<4) + (val)%10)
37
38static unsigned char days_in_mo[] =
39{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
40
41static char rtc_status;
42
43static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
44 unsigned long arg)
45{
46 volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
47 unsigned char msr;
48 unsigned long flags;
49 struct rtc_time wtime;
50
51 switch (cmd) {
52 case RTC_RD_TIME: /* Read the time/date from RTC */
53 {
54 local_irq_save(flags);
55 /* Ensure clock and real-time-mode-register are accessible */
56 msr = rtc->msr & 0xc0;
57 rtc->msr = 0x40;
58 memset(&wtime, 0, sizeof(struct rtc_time));
59 do {
60 wtime.tm_sec = BCD2BIN(rtc->bcd_sec);
61 wtime.tm_min = BCD2BIN(rtc->bcd_min);
62 wtime.tm_hour = BCD2BIN(rtc->bcd_hr);
63 wtime.tm_mday = BCD2BIN(rtc->bcd_dom);
64 wtime.tm_mon = BCD2BIN(rtc->bcd_mth)-1;
65 wtime.tm_year = BCD2BIN(rtc->bcd_year);
66 if (wtime.tm_year < 70)
67 wtime.tm_year += 100;
68 wtime.tm_wday = BCD2BIN(rtc->bcd_dow)-1;
69 } while (wtime.tm_sec != BCD2BIN(rtc->bcd_sec));
70 rtc->msr = msr;
71 local_irq_restore(flags);
72 return copy_to_user((void *)arg, &wtime, sizeof wtime) ?
73 -EFAULT : 0;
74 }
75 case RTC_SET_TIME: /* Set the RTC */
76 {
77 struct rtc_time rtc_tm;
78 unsigned char mon, day, hrs, min, sec, leap_yr;
79 unsigned int yrs;
80
81 if (!capable(CAP_SYS_ADMIN))
82 return -EACCES;
83
84 if (copy_from_user(&rtc_tm, (struct rtc_time*)arg,
85 sizeof(struct rtc_time)))
86 return -EFAULT;
87
88 yrs = rtc_tm.tm_year;
89 if (yrs < 1900)
90 yrs += 1900;
91 mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
92 day = rtc_tm.tm_mday;
93 hrs = rtc_tm.tm_hour;
94 min = rtc_tm.tm_min;
95 sec = rtc_tm.tm_sec;
96
97 leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
98
99 if ((mon > 12) || (mon < 1) || (day == 0))
100 return -EINVAL;
101
102 if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
103 return -EINVAL;
104
105 if ((hrs >= 24) || (min >= 60) || (sec >= 60))
106 return -EINVAL;
107
108 if (yrs >= 2070)
109 return -EINVAL;
110
111 local_irq_save(flags);
112 /* Ensure clock and real-time-mode-register are accessible */
113 msr = rtc->msr & 0xc0;
114 rtc->msr = 0x40;
115
116 rtc->t0cr_rtmr = yrs%4;
117 rtc->bcd_tenms = 0;
118 rtc->bcd_sec = BIN2BCD(sec);
119 rtc->bcd_min = BIN2BCD(min);
120 rtc->bcd_hr = BIN2BCD(hrs);
121 rtc->bcd_dom = BIN2BCD(day);
122 rtc->bcd_mth = BIN2BCD(mon);
123 rtc->bcd_year = BIN2BCD(yrs%100);
124 if (rtc_tm.tm_wday >= 0)
125 rtc->bcd_dow = BIN2BCD(rtc_tm.tm_wday+1);
126 rtc->t0cr_rtmr = yrs%4 | 0x08;
127
128 rtc->msr = msr;
129 local_irq_restore(flags);
130 return 0;
131 }
132 default:
133 return -EINVAL;
134 }
135}
136
137/*
138 * We enforce only one user at a time here with the open/close.
139 * Also clear the previous interrupt data on an open, and clean
140 * up things on a close.
141 */
142
143static int rtc_open(struct inode *inode, struct file *file)
144{
145 if(rtc_status)
146 return -EBUSY;
147
148 rtc_status = 1;
149 return 0;
150}
151
152static int rtc_release(struct inode *inode, struct file *file)
153{
154 lock_kernel();
155 rtc_status = 0;
156 unlock_kernel();
157 return 0;
158}
159
160/*
161 * The various file operations we support.
162 */
163
164static struct file_operations rtc_fops = {
165 .ioctl = rtc_ioctl,
166 .open = rtc_open,
167 .release = rtc_release,
168};
169
170static struct miscdevice rtc_dev = {
171 .minor = RTC_MINOR,
172 .name = "rtc",
173 .fops = &rtc_fops
174};
175
Christoph Hellwig573fc112005-09-06 15:16:58 -0700176static int __init rtc_DP8570A_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177{
178 if (!MACH_IS_BVME6000)
179 return -ENODEV;
180
181 printk(KERN_INFO "DP8570A Real Time Clock Driver v%s\n", RTC_VERSION);
182 return misc_register(&rtc_dev);
183}
Christoph Hellwig573fc112005-09-06 15:16:58 -0700184module_init(rtc_DP8570A_init);