ACPI: video: DMI workaround broken eMachines E510 BIOS enabling display brightness
[linux-2.6/linux-acpi-2.6.git] / arch / m68k / mvme16x / rtc.c
blobcea5e3e4e63646abf411aeb34be8172493214a34
1 /*
2 * Real Time Clock interface for Linux on the MVME16x
4 * Based on the PC driver by Paul Gortmaker.
5 */
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/smp_lock.h>
14 #include <linux/ioport.h>
15 #include <linux/capability.h>
16 #include <linux/fcntl.h>
17 #include <linux/init.h>
18 #include <linux/poll.h>
19 #include <linux/mc146818rtc.h> /* For struct rtc_time and ioctls, etc */
20 #include <linux/bcd.h>
21 #include <asm/mvme16xhw.h>
23 #include <asm/io.h>
24 #include <asm/uaccess.h>
25 #include <asm/system.h>
26 #include <asm/setup.h>
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.
35 static const unsigned char days_in_mo[] =
36 {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
38 static atomic_t rtc_ready = ATOMIC_INIT(1);
40 static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
41 unsigned long arg)
43 volatile MK48T08ptr_t rtc = (MK48T08ptr_t)MVME_RTC_BASE;
44 unsigned long flags;
45 struct rtc_time wtime;
46 void __user *argp = (void __user *)arg;
48 switch (cmd) {
49 case RTC_RD_TIME: /* Read the time/date from RTC */
51 local_irq_save(flags);
52 /* Ensure clock and real-time-mode-register are accessible */
53 rtc->ctrl = RTC_READ;
54 memset(&wtime, 0, sizeof(struct rtc_time));
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 rtc->ctrl = 0;
65 local_irq_restore(flags);
66 return copy_to_user(argp, &wtime, sizeof wtime) ?
67 -EFAULT : 0;
69 case RTC_SET_TIME: /* Set the RTC */
71 struct rtc_time rtc_tm;
72 unsigned char mon, day, hrs, min, sec, leap_yr;
73 unsigned int yrs;
75 if (!capable(CAP_SYS_ADMIN))
76 return -EACCES;
78 if (copy_from_user(&rtc_tm, argp, sizeof(struct rtc_time)))
79 return -EFAULT;
81 yrs = rtc_tm.tm_year;
82 if (yrs < 1900)
83 yrs += 1900;
84 mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
85 day = rtc_tm.tm_mday;
86 hrs = rtc_tm.tm_hour;
87 min = rtc_tm.tm_min;
88 sec = rtc_tm.tm_sec;
90 leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
92 if ((mon > 12) || (day == 0))
93 return -EINVAL;
95 if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
96 return -EINVAL;
98 if ((hrs >= 24) || (min >= 60) || (sec >= 60))
99 return -EINVAL;
101 if (yrs >= 2070)
102 return -EINVAL;
104 local_irq_save(flags);
105 rtc->ctrl = RTC_WRITE;
107 rtc->bcd_sec = bin2bcd(sec);
108 rtc->bcd_min = bin2bcd(min);
109 rtc->bcd_hr = bin2bcd(hrs);
110 rtc->bcd_dom = bin2bcd(day);
111 rtc->bcd_mth = bin2bcd(mon);
112 rtc->bcd_year = bin2bcd(yrs%100);
114 rtc->ctrl = 0;
115 local_irq_restore(flags);
116 return 0;
118 default:
119 return -EINVAL;
124 * We enforce only one user at a time here with the open/close.
125 * Also clear the previous interrupt data on an open, and clean
126 * up things on a close.
129 static int rtc_open(struct inode *inode, struct file *file)
131 lock_kernel();
132 if( !atomic_dec_and_test(&rtc_ready) )
134 atomic_inc( &rtc_ready );
135 unlock_kernel();
136 return -EBUSY;
138 unlock_kernel();
140 return 0;
143 static int rtc_release(struct inode *inode, struct file *file)
145 atomic_inc( &rtc_ready );
146 return 0;
150 * The various file operations we support.
153 static const struct file_operations rtc_fops = {
154 .ioctl = rtc_ioctl,
155 .open = rtc_open,
156 .release = rtc_release,
159 static struct miscdevice rtc_dev=
161 .minor = RTC_MINOR,
162 .name = "rtc",
163 .fops = &rtc_fops
166 static int __init rtc_MK48T08_init(void)
168 if (!MACH_IS_MVME16x)
169 return -ENODEV;
171 printk(KERN_INFO "MK48T08 Real Time Clock Driver v%s\n", RTC_VERSION);
172 return misc_register(&rtc_dev);
174 module_init(rtc_MK48T08_init);