1 files changed, 178 insertions, 0 deletions

diff --git a/drivers/sbus/char/rtc.c b/drivers/sbus/char/rtc.c
new file mode 100644
index 000000000000..bf3273eb1c8b
--- /dev/null
+++ b/drivers/sbus/char/rtc.c
@@ -0,0 +1,178 @@
+/* $Id: rtc.c,v 1.28 2001/10/08 22:19:51 davem Exp $
+ *
+ * Linux/SPARC Real Time Clock Driver
+ * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
+ *
+ * This is a little driver that lets a user-level program access
+ * the SPARC Mostek real time clock chip. It is no use unless you
+ * use the modified clock utility.
+ *
+ * Get the modified clock utility from:
+ *   ftp://vger.kernel.org/pub/linux/Sparc/userland/clock.c
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/miscdevice.h>
+#include <linux/slab.h>
+#include <linux/fcntl.h>
+#include <linux/poll.h>
+#include <linux/init.h>
+#include <linux/smp_lock.h>
+#include <asm/io.h>
+#include <asm/mostek.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/rtc.h>
+
+static int rtc_busy = 0;
+
+/* Retrieve the current date and time from the real time clock. */
+static void get_rtc_time(struct rtc_time *t)
+{
+        void * __iomem regs = mstk48t02_regs;
+        u8 tmp;
+
+        spin_lock_irq(&mostek_lock);
+
+        tmp = mostek_read(regs + MOSTEK_CREG);
+        tmp |= MSTK_CREG_READ;
+        mostek_write(regs + MOSTEK_CREG, tmp);
+
+        t->sec = MSTK_REG_SEC(regs);
+        t->min = MSTK_REG_MIN(regs);
+        t->hour = MSTK_REG_HOUR(regs);
+        t->dow = MSTK_REG_DOW(regs);
+        t->dom = MSTK_REG_DOM(regs);
+        t->month = MSTK_REG_MONTH(regs);
+        t->year = MSTK_CVT_YEAR( MSTK_REG_YEAR(regs) );
+
+        tmp = mostek_read(regs + MOSTEK_CREG);
+        tmp &= ~MSTK_CREG_READ;
+        mostek_write(regs + MOSTEK_CREG, tmp);
+
+        spin_unlock_irq(&mostek_lock);
+}
+
+/* Set the current date and time inthe real time clock. */
+void set_rtc_time(struct rtc_time *t)
+{
+        void * __iomem regs = mstk48t02_regs;
+        u8 tmp;
+
+        spin_lock_irq(&mostek_lock);
+
+        tmp = mostek_read(regs + MOSTEK_CREG);
+        tmp |= MSTK_CREG_WRITE;
+        mostek_write(regs + MOSTEK_CREG, tmp);
+
+        MSTK_SET_REG_SEC(regs,t->sec);
+        MSTK_SET_REG_MIN(regs,t->min);
+        MSTK_SET_REG_HOUR(regs,t->hour);
+        MSTK_SET_REG_DOW(regs,t->dow);
+        MSTK_SET_REG_DOM(regs,t->dom);
+        MSTK_SET_REG_MONTH(regs,t->month);
+        MSTK_SET_REG_YEAR(regs,t->year - MSTK_YEAR_ZERO);
+
+        tmp = mostek_read(regs + MOSTEK_CREG);
+        tmp &= ~MSTK_CREG_WRITE;
+        mostek_write(regs + MOSTEK_CREG, tmp);
+
+        spin_unlock_irq(&mostek_lock);
+}
+
+static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+        unsigned long arg)
+{
+        struct rtc_time rtc_tm;
+        void __user *argp = (void __user *)arg;
+
+        switch (cmd)
+        {
+        case RTCGET:
+                memset(&rtc_tm, 0, sizeof(struct rtc_time));
+                get_rtc_time(&rtc_tm);
+
+                if (copy_to_user(argp, &rtc_tm, sizeof(struct rtc_time)))
+                        return -EFAULT;
+
+                return 0;
+
+
+        case RTCSET:
+                if (!capable(CAP_SYS_TIME))
+                        return -EPERM;
+
+                if (copy_from_user(&rtc_tm, argp, sizeof(struct rtc_time)))
+                        return -EFAULT;
+
+                set_rtc_time(&rtc_tm);
+
+                return 0;
+
+        default:
+                return -EINVAL;
+        }
+}
+
+static int rtc_open(struct inode *inode, struct file *file)
+{
+        int ret;
+
+        spin_lock_irq(&mostek_lock);
+        if (rtc_busy) {
+                ret = -EBUSY;
+        } else {
+                rtc_busy = 1;
+                ret = 0;
+        }
+        spin_unlock_irq(&mostek_lock);
+
+        return ret;
+}
+
+static int rtc_release(struct inode *inode, struct file *file)
+{
+        rtc_busy = 0;
+
+        return 0;
+}
+
+static struct file_operations rtc_fops = {
+        .owner =        THIS_MODULE,
+        .llseek =       no_llseek,
+        .ioctl =        rtc_ioctl,
+        .open =         rtc_open,
+        .release =      rtc_release,
+};
+
+static struct miscdevice rtc_dev = { RTC_MINOR, "rtc", &rtc_fops };
+
+static int __init rtc_sun_init(void)
+{
+        int error;
+
+        /* It is possible we are being driven by some other RTC chip
+         * and thus another RTC driver is handling things.
+         */
+        if (mstk48t02_regs == 0)
+                return -ENODEV;
+
+        error = misc_register(&rtc_dev);
+        if (error) {
+                printk(KERN_ERR "rtc: unable to get misc minor for Mostek\n");
+                return error;
+        }
+
+        return 0;
+}
+
+static void __exit rtc_sun_cleanup(void)
+{
+        misc_deregister(&rtc_dev);
+}
+
+module_init(rtc_sun_init);
+module_exit(rtc_sun_cleanup);
+MODULE_LICENSE("GPL");