/* * Real Time Clock interface for Linux on the MVME16x * * Based on the PC driver by Paul Gortmaker. */ #define RTC_VERSION "1.00" #include <linux/types.h> #include <linux/errno.h> #include <linux/miscdevice.h> #include <linux/slab.h> #include <linux/smp_lock.h> #include <linux/ioport.h> #include <linux/capability.h> #include <linux/fcntl.h> #include <linux/init.h> #include <linux/poll.h> #include <linux/mc146818rtc.h> /* For struct rtc_time and ioctls, etc */ #include <linux/bcd.h> #include <asm/mvme16xhw.h> #include <asm/io.h> #include <asm/uaccess.h> #include <asm/system.h> #include <asm/setup.h> /* * We sponge a minor off of the misc major. No need slurping * up another valuable major dev number for this. If you add * an ioctl, make sure you don't conflict with SPARC's RTC * ioctls. */ static const unsigned char days_in_mo[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; static atomic_t rtc_ready = ATOMIC_INIT(1); static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) { volatile MK48T08ptr_t rtc = (MK48T08ptr_t)MVME_RTC_BASE; unsigned long flags; struct rtc_time wtime; void __user *argp = (void __user *)arg; switch (cmd) { case RTC_RD_TIME: /* Read the time/date from RTC */ { local_irq_save(flags); /* Ensure clock and real-time-mode-register are accessible */ rtc->ctrl = RTC_READ; memset(&wtime, 0, sizeof(struct rtc_time)); wtime.tm_sec = bcd2bin(rtc->bcd_sec); wtime.tm_min = bcd2bin(rtc->bcd_min); wtime.tm_hour = bcd2bin(rtc->bcd_hr); wtime.tm_mday = bcd2bin(rtc->bcd_dom); wtime.tm_mon = bcd2bin(rtc->bcd_mth)-1; wtime.tm_year = bcd2bin(rtc->bcd_year); if (wtime.tm_year < 70) wtime.tm_year += 100; wtime.tm_wday = bcd2bin(rtc->bcd_dow)-1; rtc->ctrl = 0; local_irq_restore(flags); return copy_to_user(argp, &wtime, sizeof wtime) ? -EFAULT : 0; } case RTC_SET_TIME: /* Set the RTC */ { struct rtc_time rtc_tm; unsigned char mon, day, hrs, min, sec, leap_yr; unsigned int yrs; if (!capable(CAP_SYS_ADMIN)) return -EACCES; if (copy_from_user(&rtc_tm, argp, sizeof(struct rtc_time))) return -EFAULT; yrs = rtc_tm.tm_year; if (yrs < 1900) yrs += 1900; mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */ day = rtc_tm.tm_mday; hrs = rtc_tm.tm_hour; min = rtc_tm.tm_min; sec = rtc_tm.tm_sec; leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400)); if ((mon > 12) || (day == 0)) return -EINVAL; if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr))) return -EINVAL; if ((hrs >= 24) || (min >= 60) || (sec >= 60)) return -EINVAL; if (yrs >= 2070) return -EINVAL; local_irq_save(flags); rtc->ctrl = RTC_WRITE; rtc->bcd_sec = bin2bcd(sec); rtc->bcd_min = bin2bcd(min); rtc->bcd_hr = bin2bcd(hrs); rtc->bcd_dom = bin2bcd(day); rtc->bcd_mth = bin2bcd(mon); rtc->bcd_year = bin2bcd(yrs%100); rtc->ctrl = 0; local_irq_restore(flags); return 0; } default: return -EINVAL; } } /* * We enforce only one user at a time here with the open/close. * Also clear the previous interrupt data on an open, and clean * up things on a close. */ static int rtc_open(struct inode *inode, struct file *file) { lock_kernel(); if( !atomic_dec_and_test(&rtc_ready) ) { atomic_inc( &rtc_ready ); unlock_kernel(); return -EBUSY; } unlock_kernel(); return 0; } static int rtc_release(struct inode *inode, struct file *file) { atomic_inc( &rtc_ready ); return 0; } /* * The various file operations we support. */ static const struct file_operations rtc_fops = { .ioctl = rtc_ioctl, .open = rtc_open, .release = rtc_release, }; static struct miscdevice rtc_dev= { .minor = RTC_MINOR, .name = "rtc", .fops = &rtc_fops }; static int __init rtc_MK48T08_init(void) { if (!MACH_IS_MVME16x) return -ENODEV; printk(KERN_INFO "MK48T08 Real Time Clock Driver v%s\n", RTC_VERSION); return misc_register(&rtc_dev); } module_init(rtc_MK48T08_init);