diff options
Diffstat (limited to 'arch/m68k/bvme6000/rtc.c')
| -rw-r--r-- | arch/m68k/bvme6000/rtc.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/arch/m68k/bvme6000/rtc.c b/arch/m68k/bvme6000/rtc.c new file mode 100644 index 00000000000..c6b2a410bf9 --- /dev/null +++ b/arch/m68k/bvme6000/rtc.c @@ -0,0 +1,182 @@ +/* + * Real Time Clock interface for Linux on the BVME6000 + * + * 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/ioport.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/smp_lock.h> +#include <asm/bvme6000hw.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. + */ + +#define BCD2BIN(val) (((val)&15) + ((val)>>4)*10) +#define BIN2BCD(val) ((((val)/10)<<4) + (val)%10) + +static unsigned char days_in_mo[] = +{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; + +static char rtc_status; + +static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, + unsigned long arg) +{ + volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE; + unsigned char msr; + unsigned long flags; + struct rtc_time wtime; + + 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 */ + msr = rtc->msr & 0xc0; + rtc->msr = 0x40; + memset(&wtime, 0, sizeof(struct rtc_time)); + do { + 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; + } while (wtime.tm_sec != BCD2BIN(rtc->bcd_sec)); + rtc->msr = msr; + local_irq_restore(flags); + return copy_to_user((void *)arg, &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, (struct rtc_time*)arg, + 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) || (mon < 1) || (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); + /* Ensure clock and real-time-mode-register are accessible */ + msr = rtc->msr & 0xc0; + rtc->msr = 0x40; + + rtc->t0cr_rtmr = yrs%4; + rtc->bcd_tenms = 0; + 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); + if (rtc_tm.tm_wday >= 0) + rtc->bcd_dow = BIN2BCD(rtc_tm.tm_wday+1); + rtc->t0cr_rtmr = yrs%4 | 0x08; + + rtc->msr = msr; + 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) +{ + if(rtc_status) + return -EBUSY; + + rtc_status = 1; + return 0; +} + +static int rtc_release(struct inode *inode, struct file *file) +{ + lock_kernel(); + rtc_status = 0; + unlock_kernel(); + return 0; +} + +/* + * The various file operations we support. + */ + +static 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 +}; + +int __init rtc_DP8570A_init(void) +{ + if (!MACH_IS_BVME6000) + return -ENODEV; + + printk(KERN_INFO "DP8570A Real Time Clock Driver v%s\n", RTC_VERSION); + return misc_register(&rtc_dev); +} + |