1/* 2 * Real Time Clock interface for Linux on the MVME16x 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> 14#include <linux/fcntl.h> 15#include <linux/init.h> 16#include <linux/poll.h> 17#include <linux/mc146818rtc.h> /* For struct rtc_time and ioctls, etc */ 18#include <linux/smp_lock.h> 19#include <asm/mvme16xhw.h> 20 21#include <asm/io.h> 22#include <asm/uaccess.h> 23#include <asm/system.h> 24#include <asm/setup.h> 25 26/* 27 * We sponge a minor off of the misc major. No need slurping 28 * up another valuable major dev number for this. If you add 29 * an ioctl, make sure you don't conflict with SPARC's RTC 30 * ioctls. 31 */ 32 33#define BCD2BIN(val) (((val)&15) + ((val)>>4)*10) 34#define BIN2BCD(val) ((((val)/10)<<4) + (val)%10) 35 36static unsigned char days_in_mo[] = 37{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; 38 39static char rtc_status = 0; 40 41static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, 42 unsigned long arg) 43{ 44 volatile MK48T08ptr_t rtc = (MK48T08ptr_t)MVME_RTC_BASE; 45 unsigned long flags; 46 struct rtc_time wtime; 47 48 switch (cmd) { 49 case RTC_RD_TIME: /* Read the time/date from RTC */ 50 { 51 save_flags(flags); 52 cli(); 53 /* Ensure clock and real-time-mode-register are accessible */ 54 rtc->ctrl = RTC_READ; 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 restore_flags(flags); 66 return copy_to_user((void *)arg, &wtime, sizeof wtime) ? 67 -EFAULT : 0; 68 } 69 case RTC_SET_TIME: /* Set the RTC */ 70 { 71 struct rtc_time rtc_tm; 72 unsigned char mon, day, hrs, min, sec, leap_yr; 73 unsigned int yrs; 74 75 if (!capable(CAP_SYS_ADMIN)) 76 return -EACCES; 77 78 if (copy_from_user(&rtc_tm, (struct rtc_time*)arg, 79 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; /* tm_mon starts at zero */ 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) || (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 save_flags(flags); 106 cli(); 107 rtc->ctrl = RTC_WRITE; 108 109 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); 115 116 rtc->ctrl = 0; 117 restore_flags(flags); 118 return 0; 119 } 120 default: 121 return -EINVAL; 122 } 123} 124 125/* 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. 129 */ 130 131static int rtc_open(struct inode *inode, struct file *file) 132{ 133 if(rtc_status) 134 return -EBUSY; 135 136 rtc_status = 1; 137 return 0; 138} 139 140static int rtc_release(struct inode *inode, struct file *file) 141{ 142 lock_kernel(); 143 rtc_status = 0; 144 unlock_kernel(); 145 return 0; 146} 147 148/* 149 * The various file operations we support. 150 */ 151 152static struct file_operations rtc_fops = { 153 ioctl: rtc_ioctl, 154 open: rtc_open, 155 release: rtc_release, 156}; 157 158static struct miscdevice rtc_dev= 159{ 160 RTC_MINOR, 161 "rtc", 162 &rtc_fops 163}; 164 165int __init rtc_MK48T08_init(void) 166{ 167 if (!MACH_IS_MVME16x) 168 return -ENODEV; 169 170 printk(KERN_INFO "MK48T08 Real Time Clock Driver v%s\n", RTC_VERSION); 171 misc_register(&rtc_dev); 172 return 0; 173} 174 175