1*b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
21da177e4SLinus Torvalds /*
31da177e4SLinus Torvalds * Real Time Clock interface for Linux on the BVME6000
41da177e4SLinus Torvalds *
51da177e4SLinus Torvalds * Based on the PC driver by Paul Gortmaker.
61da177e4SLinus Torvalds */
71da177e4SLinus Torvalds
81da177e4SLinus Torvalds #define RTC_VERSION "1.00"
91da177e4SLinus Torvalds
101da177e4SLinus Torvalds #include <linux/types.h>
111da177e4SLinus Torvalds #include <linux/errno.h>
121da177e4SLinus Torvalds #include <linux/miscdevice.h>
131da177e4SLinus Torvalds #include <linux/ioport.h>
14a9415644SRandy Dunlap #include <linux/capability.h>
151da177e4SLinus Torvalds #include <linux/fcntl.h>
161da177e4SLinus Torvalds #include <linux/init.h>
171da177e4SLinus Torvalds #include <linux/poll.h>
18573fc113SChristoph Hellwig #include <linux/module.h>
198c66854bSGeert Uytterhoeven #include <linux/rtc.h> /* For struct rtc_time and ioctls, etc */
20b8e31edcSJean Delvare #include <linux/bcd.h>
211da177e4SLinus Torvalds #include <asm/bvme6000hw.h>
221da177e4SLinus Torvalds
231da177e4SLinus Torvalds #include <asm/io.h>
247c0f6ba6SLinus Torvalds #include <linux/uaccess.h>
251da177e4SLinus Torvalds #include <asm/setup.h>
261da177e4SLinus Torvalds
271da177e4SLinus Torvalds /*
281da177e4SLinus Torvalds * We sponge a minor off of the misc major. No need slurping
291da177e4SLinus Torvalds * up another valuable major dev number for this. If you add
301da177e4SLinus Torvalds * an ioctl, make sure you don't conflict with SPARC's RTC
311da177e4SLinus Torvalds * ioctls.
321da177e4SLinus Torvalds */
331da177e4SLinus Torvalds
341da177e4SLinus Torvalds static unsigned char days_in_mo[] =
351da177e4SLinus Torvalds {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
361da177e4SLinus Torvalds
37b1f3bb49SThomas Gleixner static atomic_t rtc_status = ATOMIC_INIT(1);
381da177e4SLinus Torvalds
rtc_ioctl(struct file * file,unsigned int cmd,unsigned long arg)39b1f3bb49SThomas Gleixner static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
401da177e4SLinus Torvalds {
411da177e4SLinus Torvalds volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
421da177e4SLinus Torvalds unsigned char msr;
431da177e4SLinus Torvalds unsigned long flags;
441da177e4SLinus Torvalds struct rtc_time wtime;
451b7bb54aSAl Viro void __user *argp = (void __user *)arg;
461da177e4SLinus Torvalds
471da177e4SLinus Torvalds switch (cmd) {
481da177e4SLinus Torvalds case RTC_RD_TIME: /* Read the time/date from RTC */
491da177e4SLinus Torvalds {
501da177e4SLinus Torvalds local_irq_save(flags);
511da177e4SLinus Torvalds /* Ensure clock and real-time-mode-register are accessible */
521da177e4SLinus Torvalds msr = rtc->msr & 0xc0;
531da177e4SLinus Torvalds rtc->msr = 0x40;
541da177e4SLinus Torvalds memset(&wtime, 0, sizeof(struct rtc_time));
551da177e4SLinus Torvalds do {
565b1d5f95SAdrian Bunk wtime.tm_sec = bcd2bin(rtc->bcd_sec);
575b1d5f95SAdrian Bunk wtime.tm_min = bcd2bin(rtc->bcd_min);
585b1d5f95SAdrian Bunk wtime.tm_hour = bcd2bin(rtc->bcd_hr);
595b1d5f95SAdrian Bunk wtime.tm_mday = bcd2bin(rtc->bcd_dom);
605b1d5f95SAdrian Bunk wtime.tm_mon = bcd2bin(rtc->bcd_mth)-1;
615b1d5f95SAdrian Bunk wtime.tm_year = bcd2bin(rtc->bcd_year);
621da177e4SLinus Torvalds if (wtime.tm_year < 70)
631da177e4SLinus Torvalds wtime.tm_year += 100;
645b1d5f95SAdrian Bunk wtime.tm_wday = bcd2bin(rtc->bcd_dow)-1;
655b1d5f95SAdrian Bunk } while (wtime.tm_sec != bcd2bin(rtc->bcd_sec));
661da177e4SLinus Torvalds rtc->msr = msr;
671da177e4SLinus Torvalds local_irq_restore(flags);
681b7bb54aSAl Viro return copy_to_user(argp, &wtime, sizeof wtime) ?
691da177e4SLinus Torvalds -EFAULT : 0;
701da177e4SLinus Torvalds }
711da177e4SLinus Torvalds case RTC_SET_TIME: /* Set the RTC */
721da177e4SLinus Torvalds {
731da177e4SLinus Torvalds struct rtc_time rtc_tm;
741da177e4SLinus Torvalds unsigned char mon, day, hrs, min, sec, leap_yr;
751da177e4SLinus Torvalds unsigned int yrs;
761da177e4SLinus Torvalds
771da177e4SLinus Torvalds if (!capable(CAP_SYS_ADMIN))
781da177e4SLinus Torvalds return -EACCES;
791da177e4SLinus Torvalds
801b7bb54aSAl Viro if (copy_from_user(&rtc_tm, argp, sizeof(struct rtc_time)))
811da177e4SLinus Torvalds return -EFAULT;
821da177e4SLinus Torvalds
831da177e4SLinus Torvalds yrs = rtc_tm.tm_year;
841da177e4SLinus Torvalds if (yrs < 1900)
851da177e4SLinus Torvalds yrs += 1900;
861da177e4SLinus Torvalds mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
871da177e4SLinus Torvalds day = rtc_tm.tm_mday;
881da177e4SLinus Torvalds hrs = rtc_tm.tm_hour;
891da177e4SLinus Torvalds min = rtc_tm.tm_min;
901da177e4SLinus Torvalds sec = rtc_tm.tm_sec;
911da177e4SLinus Torvalds
921da177e4SLinus Torvalds leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
931da177e4SLinus Torvalds
941da177e4SLinus Torvalds if ((mon > 12) || (mon < 1) || (day == 0))
951da177e4SLinus Torvalds return -EINVAL;
961da177e4SLinus Torvalds
971da177e4SLinus Torvalds if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
981da177e4SLinus Torvalds return -EINVAL;
991da177e4SLinus Torvalds
1001da177e4SLinus Torvalds if ((hrs >= 24) || (min >= 60) || (sec >= 60))
1011da177e4SLinus Torvalds return -EINVAL;
1021da177e4SLinus Torvalds
1031da177e4SLinus Torvalds if (yrs >= 2070)
1041da177e4SLinus Torvalds return -EINVAL;
1051da177e4SLinus Torvalds
1061da177e4SLinus Torvalds local_irq_save(flags);
1071da177e4SLinus Torvalds /* Ensure clock and real-time-mode-register are accessible */
1081da177e4SLinus Torvalds msr = rtc->msr & 0xc0;
1091da177e4SLinus Torvalds rtc->msr = 0x40;
1101da177e4SLinus Torvalds
1111da177e4SLinus Torvalds rtc->t0cr_rtmr = yrs%4;
1121da177e4SLinus Torvalds rtc->bcd_tenms = 0;
1135b1d5f95SAdrian Bunk rtc->bcd_sec = bin2bcd(sec);
1145b1d5f95SAdrian Bunk rtc->bcd_min = bin2bcd(min);
1155b1d5f95SAdrian Bunk rtc->bcd_hr = bin2bcd(hrs);
1165b1d5f95SAdrian Bunk rtc->bcd_dom = bin2bcd(day);
1175b1d5f95SAdrian Bunk rtc->bcd_mth = bin2bcd(mon);
1185b1d5f95SAdrian Bunk rtc->bcd_year = bin2bcd(yrs%100);
1191da177e4SLinus Torvalds if (rtc_tm.tm_wday >= 0)
1205b1d5f95SAdrian Bunk rtc->bcd_dow = bin2bcd(rtc_tm.tm_wday+1);
1211da177e4SLinus Torvalds rtc->t0cr_rtmr = yrs%4 | 0x08;
1221da177e4SLinus Torvalds
1231da177e4SLinus Torvalds rtc->msr = msr;
1241da177e4SLinus Torvalds local_irq_restore(flags);
1251da177e4SLinus Torvalds return 0;
1261da177e4SLinus Torvalds }
1271da177e4SLinus Torvalds default:
1281da177e4SLinus Torvalds return -EINVAL;
1291da177e4SLinus Torvalds }
1301da177e4SLinus Torvalds }
1311da177e4SLinus Torvalds
1321da177e4SLinus Torvalds /*
1331da177e4SLinus Torvalds * We enforce only one user at a time here with the open/close.
1341da177e4SLinus Torvalds */
rtc_open(struct inode * inode,struct file * file)1351da177e4SLinus Torvalds static int rtc_open(struct inode *inode, struct file *file)
1361da177e4SLinus Torvalds {
137b1f3bb49SThomas Gleixner if (!atomic_dec_and_test(&rtc_status)) {
138b1f3bb49SThomas Gleixner atomic_inc(&rtc_status);
1391da177e4SLinus Torvalds return -EBUSY;
140122bc5eaSArnd Bergmann }
1411da177e4SLinus Torvalds return 0;
1421da177e4SLinus Torvalds }
1431da177e4SLinus Torvalds
rtc_release(struct inode * inode,struct file * file)1441da177e4SLinus Torvalds static int rtc_release(struct inode *inode, struct file *file)
1451da177e4SLinus Torvalds {
146b1f3bb49SThomas Gleixner atomic_inc(&rtc_status);
1471da177e4SLinus Torvalds return 0;
1481da177e4SLinus Torvalds }
1491da177e4SLinus Torvalds
1501da177e4SLinus Torvalds /*
1511da177e4SLinus Torvalds * The various file operations we support.
1521da177e4SLinus Torvalds */
1531da177e4SLinus Torvalds
1545dfe4c96SArjan van de Ven static const struct file_operations rtc_fops = {
155b1f3bb49SThomas Gleixner .unlocked_ioctl = rtc_ioctl,
1561da177e4SLinus Torvalds .open = rtc_open,
1571da177e4SLinus Torvalds .release = rtc_release,
1586038f373SArnd Bergmann .llseek = noop_llseek,
1591da177e4SLinus Torvalds };
1601da177e4SLinus Torvalds
1611da177e4SLinus Torvalds static struct miscdevice rtc_dev = {
1621da177e4SLinus Torvalds .minor = RTC_MINOR,
1631da177e4SLinus Torvalds .name = "rtc",
1641da177e4SLinus Torvalds .fops = &rtc_fops
1651da177e4SLinus Torvalds };
1661da177e4SLinus Torvalds
rtc_DP8570A_init(void)167573fc113SChristoph Hellwig static int __init rtc_DP8570A_init(void)
1681da177e4SLinus Torvalds {
1691da177e4SLinus Torvalds if (!MACH_IS_BVME6000)
1701da177e4SLinus Torvalds return -ENODEV;
1711da177e4SLinus Torvalds
1720269be79SGeert Uytterhoeven pr_info("DP8570A Real Time Clock Driver v%s\n", RTC_VERSION);
1731da177e4SLinus Torvalds return misc_register(&rtc_dev);
1741da177e4SLinus Torvalds }
175573fc113SChristoph Hellwig module_init(rtc_DP8570A_init);
176