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-rw-r--r--drivers/sbus/char/rtc.c178
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 0000000..bf3273e
--- /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");
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