blob: 15c16b62dff5cf604c029ff34f59fbe281f07476 [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>
Jean Delvareb8e31ed2006-03-23 03:00:09 -080021#include <linux/bcd.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <asm/bvme6000hw.h>
23
24#include <asm/io.h>
25#include <asm/uaccess.h>
26#include <asm/system.h>
27#include <asm/setup.h>
28
29/*
30 * We sponge a minor off of the misc major. No need slurping
31 * up another valuable major dev number for this. If you add
32 * an ioctl, make sure you don't conflict with SPARC's RTC
33 * ioctls.
34 */
35
Linus Torvalds1da177e2005-04-16 15:20:36 -070036static unsigned char days_in_mo[] =
37{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
38
39static char rtc_status;
40
41static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
42 unsigned long arg)
43{
44 volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
45 unsigned char msr;
46 unsigned long flags;
47 struct rtc_time wtime;
Al Viro1b7bb542006-01-12 01:06:26 -080048 void __user *argp = (void __user *)arg;
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
50 switch (cmd) {
51 case RTC_RD_TIME: /* Read the time/date from RTC */
52 {
53 local_irq_save(flags);
54 /* Ensure clock and real-time-mode-register are accessible */
55 msr = rtc->msr & 0xc0;
56 rtc->msr = 0x40;
57 memset(&wtime, 0, sizeof(struct rtc_time));
58 do {
59 wtime.tm_sec = BCD2BIN(rtc->bcd_sec);
60 wtime.tm_min = BCD2BIN(rtc->bcd_min);
61 wtime.tm_hour = BCD2BIN(rtc->bcd_hr);
62 wtime.tm_mday = BCD2BIN(rtc->bcd_dom);
63 wtime.tm_mon = BCD2BIN(rtc->bcd_mth)-1;
64 wtime.tm_year = BCD2BIN(rtc->bcd_year);
65 if (wtime.tm_year < 70)
66 wtime.tm_year += 100;
67 wtime.tm_wday = BCD2BIN(rtc->bcd_dow)-1;
68 } while (wtime.tm_sec != BCD2BIN(rtc->bcd_sec));
69 rtc->msr = msr;
70 local_irq_restore(flags);
Al Viro1b7bb542006-01-12 01:06:26 -080071 return copy_to_user(argp, &wtime, sizeof wtime) ?
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 -EFAULT : 0;
73 }
74 case RTC_SET_TIME: /* Set the RTC */
75 {
76 struct rtc_time rtc_tm;
77 unsigned char mon, day, hrs, min, sec, leap_yr;
78 unsigned int yrs;
79
80 if (!capable(CAP_SYS_ADMIN))
81 return -EACCES;
82
Al Viro1b7bb542006-01-12 01:06:26 -080083 if (copy_from_user(&rtc_tm, argp, sizeof(struct rtc_time)))
Linus Torvalds1da177e2005-04-16 15:20:36 -070084 return -EFAULT;
85
86 yrs = rtc_tm.tm_year;
87 if (yrs < 1900)
88 yrs += 1900;
89 mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
90 day = rtc_tm.tm_mday;
91 hrs = rtc_tm.tm_hour;
92 min = rtc_tm.tm_min;
93 sec = rtc_tm.tm_sec;
94
95 leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
96
97 if ((mon > 12) || (mon < 1) || (day == 0))
98 return -EINVAL;
99
100 if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
101 return -EINVAL;
102
103 if ((hrs >= 24) || (min >= 60) || (sec >= 60))
104 return -EINVAL;
105
106 if (yrs >= 2070)
107 return -EINVAL;
108
109 local_irq_save(flags);
110 /* Ensure clock and real-time-mode-register are accessible */
111 msr = rtc->msr & 0xc0;
112 rtc->msr = 0x40;
113
114 rtc->t0cr_rtmr = yrs%4;
115 rtc->bcd_tenms = 0;
116 rtc->bcd_sec = BIN2BCD(sec);
117 rtc->bcd_min = BIN2BCD(min);
118 rtc->bcd_hr = BIN2BCD(hrs);
119 rtc->bcd_dom = BIN2BCD(day);
120 rtc->bcd_mth = BIN2BCD(mon);
121 rtc->bcd_year = BIN2BCD(yrs%100);
122 if (rtc_tm.tm_wday >= 0)
123 rtc->bcd_dow = BIN2BCD(rtc_tm.tm_wday+1);
124 rtc->t0cr_rtmr = yrs%4 | 0x08;
125
126 rtc->msr = msr;
127 local_irq_restore(flags);
128 return 0;
129 }
130 default:
131 return -EINVAL;
132 }
133}
134
135/*
136 * We enforce only one user at a time here with the open/close.
137 * Also clear the previous interrupt data on an open, and clean
138 * up things on a close.
139 */
140
141static int rtc_open(struct inode *inode, struct file *file)
142{
143 if(rtc_status)
144 return -EBUSY;
145
146 rtc_status = 1;
147 return 0;
148}
149
150static int rtc_release(struct inode *inode, struct file *file)
151{
152 lock_kernel();
153 rtc_status = 0;
154 unlock_kernel();
155 return 0;
156}
157
158/*
159 * The various file operations we support.
160 */
161
162static struct file_operations rtc_fops = {
163 .ioctl = rtc_ioctl,
164 .open = rtc_open,
165 .release = rtc_release,
166};
167
168static struct miscdevice rtc_dev = {
169 .minor = RTC_MINOR,
170 .name = "rtc",
171 .fops = &rtc_fops
172};
173
Christoph Hellwig573fc112005-09-06 15:16:58 -0700174static int __init rtc_DP8570A_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175{
176 if (!MACH_IS_BVME6000)
177 return -ENODEV;
178
179 printk(KERN_INFO "DP8570A Real Time Clock Driver v%s\n", RTC_VERSION);
180 return misc_register(&rtc_dev);
181}
Christoph Hellwig573fc112005-09-06 15:16:58 -0700182module_init(rtc_DP8570A_init);