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-rw-r--r--package/kernel/rtc-rv5c386a/src/rtc.c613
1 files changed, 613 insertions, 0 deletions
diff --git a/package/kernel/rtc-rv5c386a/src/rtc.c b/package/kernel/rtc-rv5c386a/src/rtc.c
new file mode 100644
index 0000000..2fc6f09
--- /dev/null
+++ b/package/kernel/rtc-rv5c386a/src/rtc.c
@@ -0,0 +1,613 @@
+/*
+ * 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/mc146818rtc.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/rtc.h>
+#include <linux/delay.h>
+#include <linux/version.h>
+#include <linux/gpio.h>
+#include <linux/uaccess.h>
+
+#include <asm/current.h>
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3,4,0)
+#include <asm/system.h>
+#endif
+
+#include <bcm47xx.h>
+#include <bcm47xx_nvram.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. */
+
+/* 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. */
+module_param(rtc_debug, int, 0);
+
+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 */
+ // ssb_gpio_control(&ssb, 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).
+ */
+
+ spin_lock_irq(&rtc_lock);
+ 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();
+ spin_unlock_irq(&rtc_lock);
+
+ 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;
+ }
+
+ spin_lock_irq(&rtc_lock);
+ 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();
+ spin_unlock_irq(&rtc_lock);
+}
+
+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_do_ioctl(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 long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ long ret;
+ ret = rtc_do_ioctl(cmd, arg);
+ return ret;
+}
+
+static const struct file_operations rtc_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .read = rtc_read,
+ .write = rtc_write,
+ .unlocked_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. */
+static inline int startswith (char *source, char *cmp)
+{
+ return !strncmp(source, cmp, strlen(cmp));
+}
+
+static void platform_detect(void)
+{
+ char buf[20];
+ int et0phyaddr, et1phyaddr;
+
+ /* Based on "model_no". */
+ if (bcm47xx_nvram_getenv("model_no", buf, sizeof(buf)) >= 0) {
+ if (startswith(buf, "WL700")) { /* WL700* */
+ sda_index = 2;
+ scl_index = 5;
+ return;
+ }
+ }
+
+ if (bcm47xx_nvram_getenv("et0phyaddr", buf, sizeof(buf)) >= 0 )
+ et0phyaddr = simple_strtoul(buf, NULL, 0);
+ if (bcm47xx_nvram_getenv("et1phyaddr", buf, sizeof(buf)) >= 0 )
+ et1phyaddr = simple_strtoul(buf, NULL, 0);
+
+ if (bcm47xx_nvram_getenv("hardware_version", buf, sizeof(buf)) >= 0) {
+ /* Either WL-300g or WL-HDD, do more extensive checks */
+ if (startswith(buf, "WL300-") && et0phyaddr == 0 && et1phyaddr == 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
+ */
+ spin_lock_irq(&rtc_lock);
+ 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();
+ spin_unlock_irq(&rtc_lock);
+ if ((cr1 & RTC_24HOUR_MODE_MASK) == 0) {
+ /* RTC is running in 12h mode */
+ printk(KERN_INFO "rtc.o: switching to 24h mode\n");
+ spin_lock_irq(&rtc_lock);
+ i2c_start();
+ i2c_outb(RTC_I2C_ADDRESS | I2C_WRITE_MASK);
+ i2c_outb(0xE0);
+ i2c_outb(cr1 | RTC_24HOUR_MODE_MASK);
+ i2c_stop();
+ spin_unlock_irq(&rtc_lock);
+ }
+
+ 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:
+ */
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