add RTC RV5C386A package

SVN-Revision: 17073

4 files changed, 810 insertions, 0 deletions

diff --git a/package/rtc-rv5c386a/Makefile b/package/rtc-rv5c386a/Makefile
new file mode 100644
index 0000000000..e0fde7834e
--- /dev/null
+++ b/package/rtc-rv5c386a/Makefile
@@ -0,0 +1,42 @@
+#
+# Copyright (C) 2006-2009 OpenWrt.org
+#
+# This is free software, licensed under the GNU General Public License v2.
+# See /LICENSE for more information.
+#
+
+include $(TOPDIR)/rules.mk
+include $(INCLUDE_DIR)/kernel.mk
+
+PKG_NAME:=rtc-rv5c386a
+PKG_RELEASE:=1
+
+include $(INCLUDE_DIR)/package.mk
+
+define KernelPackage/rtc-rv5c386a
+  SUBMENU:=Other modules
+  DEPENDS:=@TARGET_brcm_2_4||TARGET_brcm47xx
+  TITLE:=Driver for RTC RV5C386A (used in WL-700gE and WL-HDD)
+  AUTOLOAD:=$(call AutoLoad,70,rtc)
+  FILES:=$(PKG_BUILD_DIR)/rtc.$(LINUX_KMOD_SUFFIX)
+endef
+
+define Build/Prepare
+	mkdir -p $(PKG_BUILD_DIR)
+	$(CP) ./src/* $(PKG_BUILD_DIR)/
+endef
+
+ifeq ($(BOARD),brcm-2.4)
+	BUILDFLAGS=-DBCMDRIVER -I$(LINUX_DIR)/arch/mips/bcm947xx/include -DLINUX_2_4
+endif
+
+define Build/Compile
+	$(MAKE) -C "$(LINUX_DIR)" \
+		CROSS_COMPILE="$(TARGET_CROSS)" \
+		ARCH="$(LINUX_KARCH)" \
+		SUBDIRS="$(PKG_BUILD_DIR)" \
+		EXTRA_CFLAGS="$(BUILDFLAGS)" \
+		modules
+endef
+
+$(eval $(call KernelPackage,rtc-rv5c386a))
diff --git a/package/rtc-rv5c386a/src/Makefile b/package/rtc-rv5c386a/src/Makefile
new file mode 100644
index 0000000000..eeb0430774
--- /dev/null
+++ b/package/rtc-rv5c386a/src/Makefile
@@ -0,0 +1,18 @@
+# $Id$
+#
+# Makefile for Real Time Clock driver for WL-HDD
+#
+# Copyright (C) 2007 Andreas Engel
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version
+# 2 of the License, or (at your option) any later version.
+#
+
+obj-m := rtc.o
+
+ifeq ($(MAKING_MODULES),1)
+
+-include $(TOPDIR)/Rules.make
+endif
diff --git a/package/rtc-rv5c386a/src/gpio.h b/package/rtc-rv5c386a/src/gpio.h
new file mode 100644
index 0000000000..cd48637b20
--- /dev/null
+++ b/package/rtc-rv5c386a/src/gpio.h
@@ -0,0 +1,157 @@
+#ifndef __DIAG_GPIO_H
+#define __DIAG_GPIO_H
+#include <linux/interrupt.h>
+
+#ifndef BCMDRIVER
+#include <linux/ssb/ssb_embedded.h>
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,25)
+#include <linux/gpio.h>
+#define ssb ssb_bcm47xx
+#endif
+extern struct ssb_bus ssb;
+
+
+static inline u32 gpio_in(void)
+{
+	return ssb_gpio_in(&ssb, ~0);
+}
+
+static inline u32 gpio_out(u32 mask, u32 value)
+{
+	return ssb_gpio_out(&ssb, mask, value);
+}
+
+static inline u32 gpio_outen(u32 mask, u32 value)
+{
+	return ssb_gpio_outen(&ssb, mask, value);
+}
+
+static inline u32 gpio_control(u32 mask, u32 value)
+{
+	return ssb_gpio_control(&ssb, mask, value);
+}
+
+static inline u32 gpio_setintmask(u32 mask, u32 value)
+{
+	return ssb_gpio_intmask(&ssb, mask, value);
+}
+
+static inline u32 gpio_intpolarity(u32 mask, u32 value)
+{
+	return ssb_gpio_polarity(&ssb, mask, value);
+}
+
+static inline u32 __ssb_write32_masked(struct ssb_device *dev, u16 offset,
+				       u32 mask, u32 value)
+{
+	value &= mask;
+	value |= ssb_read32(dev, offset) & ~mask;
+	ssb_write32(dev, offset, value);
+	return value;
+}
+
+static void gpio_set_irqenable(int enabled, irqreturn_t (*handler)(int, void *))
+{
+	int irq;
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,25)
+	irq = gpio_to_irq(0);
+	if (irq == -EINVAL) return;
+#else
+	if (ssb.chipco.dev)
+		irq = ssb_mips_irq(ssb.chipco.dev) + 2;
+	else if (ssb.extif.dev)
+		irq = ssb_mips_irq(ssb.extif.dev) + 2;
+	else return;
+#endif
+	
+	if (enabled) {
+		if (request_irq(irq, handler, IRQF_SHARED | IRQF_SAMPLE_RANDOM, "gpio", handler))
+			return;
+	} else {
+		free_irq(irq, handler);
+	}
+
+	if (ssb.chipco.dev)
+		__ssb_write32_masked(ssb.chipco.dev, SSB_CHIPCO_IRQMASK, SSB_CHIPCO_IRQ_GPIO, (enabled ? SSB_CHIPCO_IRQ_GPIO : 0));
+}
+
+#else
+
+#include <typedefs.h>
+#include <osl.h>
+#include <bcmdevs.h>
+#include <sbutils.h>
+#include <sbconfig.h>
+#include <sbchipc.h>
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
+#include <sbmips.h>
+#else
+#include <hndcpu.h>
+#endif
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0)
+#define sbh bcm947xx_sbh
+#define sbh_lock bcm947xx_sbh_lock
+#endif
+
+extern void *sbh;
+extern spinlock_t sbh_lock;
+
+#define gpio_in()	sb_gpioin(sbh)
+#define gpio_out(mask, value) 	sb_gpioout(sbh, mask, ((value) & (mask)), GPIO_DRV_PRIORITY)
+#define gpio_outen(mask, value) 	sb_gpioouten(sbh, mask, value, GPIO_DRV_PRIORITY)
+#define gpio_control(mask, value) 	sb_gpiocontrol(sbh, mask, value, GPIO_DRV_PRIORITY)
+#define gpio_setintmask(mask, value) 	sb_gpiointmask(sbh, mask, value, GPIO_DRV_PRIORITY)
+#define gpio_intpolarity(mask, value) 	sb_gpiointpolarity(sbh, mask, value, GPIO_DRV_PRIORITY)
+
+static void gpio_set_irqenable(int enabled, irqreturn_t (*handler)(int, void *, struct pt_regs *))
+{
+	unsigned int coreidx;
+	unsigned long flags;
+	chipcregs_t *cc;
+	int irq;
+
+	spin_lock_irqsave(sbh_lock, flags);
+	coreidx = sb_coreidx(sbh);
+
+	irq = sb_irq(sbh) + 2;
+	if (enabled)
+		request_irq(irq, handler, SA_SHIRQ | SA_SAMPLE_RANDOM, "gpio", handler);
+	else
+		free_irq(irq, handler);
+
+	if ((cc = sb_setcore(sbh, SB_CC, 0))) {
+		int intmask;
+
+		intmask = readl(&cc->intmask);
+		if (enabled)
+			intmask |= CI_GPIO;
+		else
+			intmask &= ~CI_GPIO;
+		writel(intmask, &cc->intmask);
+	}
+	sb_setcoreidx(sbh, coreidx);
+	spin_unlock_irqrestore(sbh_lock, flags);
+}
+
+#endif /* BCMDRIVER */
+
+#define EXTIF_ADDR 0x1f000000
+#define EXTIF_UART (EXTIF_ADDR + 0x00800000)
+
+#define GPIO_TYPE_NORMAL	(0x0 << 24)
+#define GPIO_TYPE_EXTIF 	(0x1 << 24)
+#define GPIO_TYPE_MASK  	(0xf << 24)
+
+static inline void gpio_set_extif(int gpio, int value)
+{
+	volatile u8 *addr = (volatile u8 *) KSEG1ADDR(EXTIF_UART) + (gpio & ~GPIO_TYPE_MASK);
+	if (value)
+		*addr = 0xFF;
+	else
+		*addr;
+}
+
+#endif /* __DIAG_GPIO_H */
diff --git a/package/rtc-rv5c386a/src/rtc.c b/package/rtc-rv5c386a/src/rtc.c
new file mode 100644
index 0000000000..34d0a83aab
--- /dev/null
+++ b/package/rtc-rv5c386a/src/rtc.c
@@ -0,0 +1,593 @@
+/*
+ * Real Time Clock driver for WL-HDD
+ *
+ * Copyright (C) 2007 Andreas Engel
+ *
+ * Hacked together mostly by copying the relevant code parts from:
+ *   drivers/i2c/i2c-bcm5365.c
+ *   drivers/i2c/i2c-algo-bit.c
+ *   drivers/char/rtc.c
+ *
+ * Note 1:
+ * This module uses the standard char device (10,135), while the Asus module
+ * rtcdrv.o uses (12,0). So, both can coexist which might be handy during
+ * development (but see the comment in rtc_open()).
+ *
+ * Note 2:
+ * You might need to set the clock once after loading the driver the first
+ * time because the driver switches the chip into 24h mode if it is running
+ * in 12h mode.
+ *
+ * Usage:
+ * For compatibility reasons with the original asus driver, the time can be
+ * read and set via the /dev/rtc device entry. The only accepted data format
+ * is "YYYY:MM:DD:W:HH:MM:SS\n". See OpenWrt wiki for a script which handles
+ * this format.
+ *
+ * In addition, this driver supports the standard ioctl() calls for setting
+ * and reading the hardware clock, so the ordinary hwclock utility can also
+ * be used.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * TODO:
+ * - add a /proc/driver/rtc interface?
+ * - make the battery failure bit available through the /proc interface?
+ *
+ * $Id: rtc.c 7 2007-05-25 19:37:01Z ae $
+ */
+
+#include <linux/module.h>
+#include <linux/kmod.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/miscdevice.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/rtc.h>
+#include <linux/delay.h>
+#include <linux/version.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+#include "gpio.h"
+
+#define RTC_IS_OPEN		0x01	/* Means /dev/rtc is in use.  */
+
+/* Can be changed via a module parameter.  */
+static int rtc_debug = 0;
+
+static unsigned long rtc_status = 0;	/* Bitmapped status byte.	*/
+
+static spinlock_t rtc_lock = SPIN_LOCK_UNLOCKED;
+
+/* These settings are platform dependents.  */
+unsigned int sda_index = 0;
+unsigned int scl_index = 0;
+
+#define I2C_READ_MASK  1
+#define I2C_WRITE_MASK 0
+
+#define I2C_ACK 1
+#define I2C_NAK 0
+
+#define RTC_EPOCH		1900
+#define RTC_I2C_ADDRESS		(0x32 << 1)
+#define RTC_24HOUR_MODE_MASK	0x20
+#define RTC_PM_MASK		0x20
+#define RTC_VDET_MASK		0x40
+#define RTC_Y2K_MASK		0x80
+
+/*
+ * Delay in microseconds for generating the pulses on the I2C bus. We use
+ * a rather conservative setting here.  See datasheet of the RTC chip.
+ */
+#define ADAP_DELAY 50
+
+/* Avoid spurious compiler warnings.  */
+#define UNUSED __attribute__((unused))
+
+MODULE_AUTHOR("Andreas Engel");
+MODULE_LICENSE("GPL");
+
+/* Test stolen from switch-adm.c.  */
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,52)
+module_param(rtc_debug, int, 0);
+#else
+MODULE_PARM(rtc_debug, "i");
+#endif
+
+static inline void sdalo(void)
+{
+	gpio_direction_output(sda_index, 1);
+	udelay(ADAP_DELAY);
+}
+
+static inline void sdahi(void)
+{
+	gpio_direction_input(sda_index);
+	udelay(ADAP_DELAY);
+}
+
+static inline void scllo(void)
+{
+   gpio_direction_output(scl_index, 1);
+	udelay(ADAP_DELAY);
+}
+
+static inline int getscl(void)
+{
+	return (gpio_get_value(scl_index));
+}
+
+static inline int getsda(void)
+{
+	return (gpio_get_value(sda_index));
+}
+
+/*
+ * We shouldn't simply set the SCL pin to high. Like SDA, the SCL line is
+ * bidirectional too. According to the I2C spec, the slave is allowed to
+ * pull down the SCL line to slow down the clock, so we need to check this.
+ * Generally, we'd need a timeout here, but in our case, we just check the
+ * line, assuming the RTC chip behaves well.
+ */
+static int sclhi(void)
+{
+	gpio_direction_input(scl_index);
+	udelay(ADAP_DELAY);
+	if (!getscl()) {
+		printk(KERN_ERR "SCL pin should be low\n");
+		return -ETIMEDOUT;
+	}
+	return 0;
+}
+
+static void i2c_start(void)
+{
+	sdalo();
+	scllo();
+}
+
+static void i2c_stop(void)
+{
+	sdalo();
+	sclhi();
+	sdahi();
+}
+
+static int i2c_outb(int c)
+{
+	int i;
+	int ack;
+
+	/* assert: scl is low */
+	for (i = 7; i >= 0; i--) {
+		if (c & ( 1 << i )) {
+			sdahi();
+		} else {
+			sdalo();
+		}
+		if (sclhi() < 0) { /* timed out */
+			sdahi(); /* we don't want to block the net */
+			return -ETIMEDOUT;
+		};
+		scllo();
+	}
+	sdahi();
+	if (sclhi() < 0) {
+		return -ETIMEDOUT;
+	};
+	/* read ack: SDA should be pulled down by slave */
+	ack = getsda() == 0;	/* ack: sda is pulled low ->success.	 */
+	scllo();
+
+	if (rtc_debug)
+		printk(KERN_DEBUG "i2c_outb(0x%02x) -> %s\n",
+		       c, ack ? "ACK": "NAK");
+
+	return ack;		/* return 1 if device acked	 */
+	/* assert: scl is low (sda undef) */
+}
+
+static int i2c_inb(int ack)
+{
+	int i;
+	unsigned int indata = 0;
+
+	/* assert: scl is low */
+
+	sdahi();
+	for (i = 0; i < 8; i++) {
+		if (sclhi() < 0) {
+			return -ETIMEDOUT;
+		};
+		indata *= 2;
+		if (getsda())
+			indata |= 0x01;
+		scllo();
+	}
+	if (ack) {
+		sdalo();
+	} else {
+		sdahi();
+	}
+
+	if (sclhi() < 0) {
+		sdahi();
+		return -ETIMEDOUT;
+	}
+	scllo();
+	sdahi();
+
+	if (rtc_debug)
+		printk(KERN_DEBUG "i2c_inb() -> 0x%02x\n", indata);
+
+	/* assert: scl is low */
+	return indata & 0xff;
+}
+
+static void i2c_init(void)
+{
+    /* no gpio_control for EXTIF */
+	// gpio_control(sda_mask | scl_mask, 0);
+
+   gpio_set_value(sda_index, 0);
+   gpio_set_value(scl_index, 0);
+	sdahi();
+	sclhi();
+}
+
+static int rtc_open(UNUSED struct inode *inode, UNUSED struct file *filp)
+{
+	spin_lock_irq(&rtc_lock);
+
+	if (rtc_status & RTC_IS_OPEN) {
+		spin_unlock_irq(&rtc_lock);
+		return -EBUSY;
+	}
+
+	rtc_status |= RTC_IS_OPEN;
+
+	/*
+	 * The following call is only necessary if we use both this driver and
+	 * the proprietary one from asus at the same time (which, b.t.w. only
+	 * makes sense during development). Otherwise, each access via the asus
+	 * driver will make access via this driver impossible.
+	 */
+	i2c_init();
+
+	spin_unlock_irq(&rtc_lock);
+
+	return 0;
+}
+
+static int rtc_release(UNUSED struct inode *inode, UNUSED struct file *filp)
+{
+	/* No need for locking here. */
+	rtc_status &= ~RTC_IS_OPEN;
+	return 0;
+}
+
+static int from_bcd(int bcdnum)
+{
+	int fac, num = 0;
+
+	for (fac = 1; bcdnum; fac *= 10) {
+		num += (bcdnum % 16) * fac;
+		bcdnum /= 16;
+	}
+
+	return num;
+}
+
+static int to_bcd(int decnum)
+{
+	int fac, num = 0;
+
+	for (fac = 1; decnum; fac *= 16) {
+		num += (decnum % 10) * fac;
+		decnum /= 10;
+	}
+
+	return num;
+}
+
+static void get_rtc_time(struct rtc_time *rtc_tm)
+{
+	int cr2;
+
+	/*
+	 * Read date and time from the RTC. We use read method (3).
+	 */
+
+	i2c_start();
+	i2c_outb(RTC_I2C_ADDRESS | I2C_READ_MASK);
+	cr2             = i2c_inb(I2C_ACK);
+	rtc_tm->tm_sec  = i2c_inb(I2C_ACK);
+	rtc_tm->tm_min  = i2c_inb(I2C_ACK);
+	rtc_tm->tm_hour = i2c_inb(I2C_ACK);
+	rtc_tm->tm_wday = i2c_inb(I2C_ACK);
+	rtc_tm->tm_mday = i2c_inb(I2C_ACK);
+	rtc_tm->tm_mon  = i2c_inb(I2C_ACK);
+	rtc_tm->tm_year = i2c_inb(I2C_NAK);
+	i2c_stop();
+
+	if (cr2 & RTC_VDET_MASK) {
+		printk(KERN_WARNING "***RTC BATTERY FAILURE***\n");
+	}
+
+	/* Handle century bit */
+	if (rtc_tm->tm_mon & RTC_Y2K_MASK) {
+		rtc_tm->tm_mon &= ~RTC_Y2K_MASK;
+		rtc_tm->tm_year += 0x100;
+	}
+
+	rtc_tm->tm_sec  = from_bcd(rtc_tm->tm_sec);
+	rtc_tm->tm_min  = from_bcd(rtc_tm->tm_min);
+	rtc_tm->tm_hour = from_bcd(rtc_tm->tm_hour);
+	rtc_tm->tm_mday = from_bcd(rtc_tm->tm_mday);
+	rtc_tm->tm_mon  = from_bcd(rtc_tm->tm_mon) - 1;
+	rtc_tm->tm_year = from_bcd(rtc_tm->tm_year);
+
+	rtc_tm->tm_isdst = -1; /* DST not known */
+}
+
+static void set_rtc_time(struct rtc_time *rtc_tm)
+{
+	rtc_tm->tm_sec  = to_bcd(rtc_tm->tm_sec);
+	rtc_tm->tm_min  = to_bcd(rtc_tm->tm_min);
+	rtc_tm->tm_hour = to_bcd(rtc_tm->tm_hour);
+	rtc_tm->tm_mday = to_bcd(rtc_tm->tm_mday);
+	rtc_tm->tm_mon  = to_bcd(rtc_tm->tm_mon + 1);
+	rtc_tm->tm_year = to_bcd(rtc_tm->tm_year);
+
+	if (rtc_tm->tm_year >= 0x100) {
+		rtc_tm->tm_year -= 0x100;
+		rtc_tm->tm_mon |= RTC_Y2K_MASK;
+	}
+
+	i2c_start();
+	i2c_outb(RTC_I2C_ADDRESS | I2C_WRITE_MASK);
+	i2c_outb(0x00);	/* set starting register to 0 (=seconds) */
+	i2c_outb(rtc_tm->tm_sec);
+	i2c_outb(rtc_tm->tm_min);
+	i2c_outb(rtc_tm->tm_hour);
+	i2c_outb(rtc_tm->tm_wday);
+	i2c_outb(rtc_tm->tm_mday);
+	i2c_outb(rtc_tm->tm_mon);
+	i2c_outb(rtc_tm->tm_year);
+	i2c_stop();
+}
+
+static ssize_t rtc_write(UNUSED struct file *filp, const char *buf,
+                         size_t count, loff_t *ppos)
+{
+	struct rtc_time rtc_tm;
+	char buffer[23];
+	char *p;
+
+	if (!capable(CAP_SYS_TIME))
+		return -EACCES;
+
+	if (ppos != &filp->f_pos)
+		return -ESPIPE;
+
+	/*
+	 * For simplicity, the only acceptable format is:
+	 * YYYY:MM:DD:W:HH:MM:SS\n
+	 */
+
+	if (count != 22)
+		goto err_out;
+
+	if (copy_from_user(buffer, buf, count))
+		return -EFAULT;
+
+	buffer[sizeof(buffer)-1] = '\0';
+
+	p = &buffer[0];
+
+	rtc_tm.tm_year  = simple_strtoul(p, &p, 10);
+	if (*p++ != ':') goto err_out;
+
+	rtc_tm.tm_mon = simple_strtoul(p, &p, 10) - 1;
+	if (*p++ != ':') goto err_out;
+
+	rtc_tm.tm_mday = simple_strtoul(p, &p, 10);
+	if (*p++ != ':') goto err_out;
+
+	rtc_tm.tm_wday = simple_strtoul(p, &p, 10);
+	if (*p++ != ':') goto err_out;
+
+	rtc_tm.tm_hour = simple_strtoul(p, &p, 10);
+	if (*p++ != ':') goto err_out;
+
+	rtc_tm.tm_min = simple_strtoul(p, &p, 10);
+	if (*p++ != ':') goto err_out;
+
+	rtc_tm.tm_sec = simple_strtoul(p, &p, 10);
+	if (*p != '\n') goto err_out;
+
+	rtc_tm.tm_year -= RTC_EPOCH;
+
+	set_rtc_time(&rtc_tm);
+
+	*ppos += count;
+
+	return count;
+
+ err_out:
+	printk(KERN_ERR "invalid format: use YYYY:MM:DD:W:HH:MM:SS\\n\n");
+	return -EINVAL;
+}
+
+
+static ssize_t rtc_read(UNUSED struct file *filp, char *buf, size_t count,
+                        loff_t *ppos)
+{
+	char wbuf[23];
+	struct rtc_time tm;
+	ssize_t len;
+
+	if (count == 0 || *ppos != 0)
+		return 0;
+
+	get_rtc_time(&tm);
+
+	len = sprintf(wbuf, "%04d:%02d:%02d:%d:%02d:%02d:%02d\n",
+		      tm.tm_year + RTC_EPOCH,
+		      tm.tm_mon + 1,
+		      tm.tm_mday,
+		      tm.tm_wday,
+		      tm.tm_hour,
+		      tm.tm_min,
+		      tm.tm_sec);
+
+	if (len > (ssize_t)count)
+		len = count;
+
+	if (copy_to_user(buf, wbuf, len))
+		return -EFAULT;
+
+	*ppos += len;
+
+	return len;
+}
+
+static int rtc_ioctl(UNUSED struct inode *inode, UNUSED struct file *filp,
+		     unsigned int cmd, unsigned long arg)
+{
+	struct rtc_time rtc_tm;
+
+	switch (cmd) {
+		case RTC_RD_TIME:
+			memset(&rtc_tm, 0, sizeof(struct rtc_time));
+			get_rtc_time(&rtc_tm);
+			if (copy_to_user((void *)arg, &rtc_tm, sizeof(rtc_tm)))
+				return -EFAULT;
+			break;
+
+		case RTC_SET_TIME:
+			if (!capable(CAP_SYS_TIME))
+				return -EACCES;
+
+			if (copy_from_user(&rtc_tm, (struct rtc_time *)arg,
+					   sizeof(struct rtc_time)))
+				return -EFAULT;
+
+			set_rtc_time(&rtc_tm);
+			break;
+
+		default:
+			return -ENOTTY;
+	}
+
+	return 0;
+}
+
+static struct file_operations rtc_fops = {
+	.owner   = THIS_MODULE,
+	.llseek  = no_llseek,
+	.read    = rtc_read,
+	.write   = rtc_write,
+	.ioctl   = rtc_ioctl,
+	.open    = rtc_open,
+	.release = rtc_release,
+};
+
+static struct miscdevice rtc_dev = {
+	.minor = RTC_MINOR,
+	.name  = "rtc",
+	.fops  = &rtc_fops,
+};
+
+/* Savagely ripped from diag.c.  */
+extern char *nvram_get(char *str);
+#define getvar(str) (nvram_get(str)?:"")
+static inline int startswith (char *source, char *cmp)
+{	return !strncmp(source,cmp,strlen(cmp)); }
+static void platform_detect(void)
+{
+	char *buf;
+
+	/* Based on "model_no".  */
+	if ((buf = nvram_get("model_no"))) {
+		if (startswith(buf,"WL700")) { /* WL700* */
+			sda_index = 2;
+			scl_index = 5;
+			return;
+		}
+	}
+
+	if (startswith(getvar("hardware_version"), "WL300-")) {
+		/* Either WL-300g or WL-HDD, do more extensive checks */
+		if ((simple_strtoul(getvar("et0phyaddr"), NULL, 0) == 0) &&
+			 (simple_strtoul(getvar("et1phyaddr"), NULL, 0) == 1)) {
+			sda_index = 4;
+			scl_index = 5;
+			return;
+		}
+	}
+	/* not found */
+}
+
+static int __init rtc_init(void)
+{
+	int cr1;
+
+	platform_detect();
+
+	if (sda_index == scl_index) {
+		printk(KERN_ERR "RTC-RV5C386A: unrecognized platform!\n");
+		return -ENODEV;
+	}
+
+	i2c_init();
+
+	/*
+	 * Switch RTC to 24h mode
+	 */
+	i2c_start();
+	i2c_outb(RTC_I2C_ADDRESS | I2C_WRITE_MASK);
+	i2c_outb(0xE4); /* start at address 0xE, transmission mode 4 */
+	cr1 = i2c_inb(I2C_NAK);
+	i2c_stop();
+	if ((cr1 & RTC_24HOUR_MODE_MASK) == 0) {
+		/* RTC is running in 12h mode */
+		printk(KERN_INFO "rtc.o: switching to 24h mode\n");
+		i2c_start();
+		i2c_outb(RTC_I2C_ADDRESS | I2C_WRITE_MASK);
+		i2c_outb(0xE0);
+		i2c_outb(cr1 | RTC_24HOUR_MODE_MASK);
+		i2c_stop();
+	}
+
+	misc_register(&rtc_dev);
+
+	printk(KERN_INFO "RV5C386A Real Time Clock Driver loaded\n");
+
+	return 0;
+}
+
+static void __exit rtc_exit (void)
+{
+	misc_deregister(&rtc_dev);
+	printk(KERN_INFO "Successfully removed RTC RV5C386A driver\n");
+}
+
+module_init(rtc_init);
+module_exit(rtc_exit);
+
+/*
+ * Local Variables:
+ * indent-tabs-mode:t
+ * c-basic-offset:8
+ * End:
+ */