2 * Real Time Clock interface for Linux on the MVME16x
4 * Based on the PC driver by Paul Gortmaker.
7 #define RTC_VERSION "1.00"
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>
14 #include <linux/capability.h>
15 #include <linux/fcntl.h>
16 #include <linux/init.h>
17 #include <linux/poll.h>
18 #include <linux/mc146818rtc.h> /* For struct rtc_time and ioctls, etc */
19 #include <linux/smp_lock.h>
20 #include <asm/mvme16xhw.h>
23 #include <asm/uaccess.h>
24 #include <asm/system.h>
25 #include <asm/setup.h>
28 * We sponge a minor off of the misc major. No need slurping
29 * up another valuable major dev number for this. If you add
30 * an ioctl, make sure you don't conflict with SPARC's RTC
34 #define BCD2BIN(val) (((val)&15) + ((val)>>4)*10)
35 #define BIN2BCD(val) ((((val)/10)<<4) + (val)%10)
37 static const unsigned char days_in_mo[] =
38 {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
40 static atomic_t rtc_ready = ATOMIC_INIT(1);
42 static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
45 volatile MK48T08ptr_t rtc = (MK48T08ptr_t)MVME_RTC_BASE;
47 struct rtc_time wtime;
48 void __user *argp = (void __user *)arg;
51 case RTC_RD_TIME: /* Read the time/date from RTC */
53 local_irq_save(flags);
54 /* Ensure clock and real-time-mode-register are accessible */
56 memset(&wtime, 0, sizeof(struct rtc_time));
57 wtime.tm_sec = BCD2BIN(rtc->bcd_sec);
58 wtime.tm_min = BCD2BIN(rtc->bcd_min);
59 wtime.tm_hour = BCD2BIN(rtc->bcd_hr);
60 wtime.tm_mday = BCD2BIN(rtc->bcd_dom);
61 wtime.tm_mon = BCD2BIN(rtc->bcd_mth)-1;
62 wtime.tm_year = BCD2BIN(rtc->bcd_year);
63 if (wtime.tm_year < 70)
65 wtime.tm_wday = BCD2BIN(rtc->bcd_dow)-1;
67 local_irq_restore(flags);
68 return copy_to_user(argp, &wtime, sizeof wtime) ?
71 case RTC_SET_TIME: /* Set the RTC */
73 struct rtc_time rtc_tm;
74 unsigned char mon, day, hrs, min, sec, leap_yr;
77 if (!capable(CAP_SYS_ADMIN))
80 if (copy_from_user(&rtc_tm, argp, sizeof(struct rtc_time)))
86 mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
92 leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
94 if ((mon > 12) || (day == 0))
97 if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
100 if ((hrs >= 24) || (min >= 60) || (sec >= 60))
106 local_irq_save(flags);
107 rtc->ctrl = RTC_WRITE;
109 rtc->bcd_sec = BIN2BCD(sec);
110 rtc->bcd_min = BIN2BCD(min);
111 rtc->bcd_hr = BIN2BCD(hrs);
112 rtc->bcd_dom = BIN2BCD(day);
113 rtc->bcd_mth = BIN2BCD(mon);
114 rtc->bcd_year = BIN2BCD(yrs%100);
117 local_irq_restore(flags);
126 * We enforce only one user at a time here with the open/close.
127 * Also clear the previous interrupt data on an open, and clean
128 * up things on a close.
131 static int rtc_open(struct inode *inode, struct file *file)
133 if( !atomic_dec_and_test(&rtc_ready) )
135 atomic_inc( &rtc_ready );
142 static int rtc_release(struct inode *inode, struct file *file)
144 atomic_inc( &rtc_ready );
149 * The various file operations we support.
152 static struct file_operations rtc_fops = {
155 .release = rtc_release,
158 static struct miscdevice rtc_dev=
165 static int __init rtc_MK48T08_init(void)
167 if (!MACH_IS_MVME16x)
170 printk(KERN_INFO "MK48T08 Real Time Clock Driver v%s\n", RTC_VERSION);
171 return misc_register(&rtc_dev);
173 module_init(rtc_MK48T08_init);