+++ /dev/null
-/*
- * drivers/watchdog/ubi32_wdt.c
- * Ubicom32 Watchdog Driver
- *
- * Originally based on softdog.c
- * Copyright 2006-2007 Analog Devices Inc.
- * Copyright 2006-2007 Michele d'Amico
- * Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>
- * (C) Copyright 2009, Ubicom, Inc.
- *
- * This file is part of the Ubicom32 Linux Kernel Port.
- *
- * The Ubicom32 Linux Kernel Port 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.
- *
- * The Ubicom32 Linux Kernel Port is distributed in the hope that it
- * will be useful, but WITHOUT ANY WARRANTY; without even the implied
- * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
- * the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with the Ubicom32 Linux Kernel Port. If not,
- * see <http://www.gnu.org/licenses/>.
- *
- * Ubicom32 implementation derived from (with many thanks):
- * arch/m68knommu
- * arch/blackfin
- * arch/parisc
- */
-#include <linux/platform_device.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/types.h>
-#include <linux/timer.h>
-#include <linux/miscdevice.h>
-#include <linux/watchdog.h>
-#include <linux/fs.h>
-#include <linux/notifier.h>
-#include <linux/reboot.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/uaccess.h>
-#include <asm/ip5000.h>
-
-#define WATCHDOG_NAME "ubi32-wdt"
-#define PFX WATCHDOG_NAME ": "
-
-#define OSC1_FREQ 12000000
-#define WATCHDOG_SEC_TO_CYC(x) (OSC1_FREQ * (x))
-#define WATCHDOG_MAX_SEC (0xffffffff / OSC1_FREQ)
-
-#define MIN_PROCESSOR_ADDRESS 0x03000000
-
-static DEFINE_SPINLOCK(ubi32_wdt_spinlock);
-
-#define WATCHDOG_TIMEOUT 20
-
-#if defined(CONFIG_WATCHDOG_NOWAYOUT)
-#define WATCHDOG_NOWAYOUT 1
-#else
-#define WATCHDOG_NOWAYOUT 0
-#endif
-
-static unsigned int timeout = WATCHDOG_TIMEOUT;
-static int nowayout = WATCHDOG_NOWAYOUT;
-static struct watchdog_info ubi32_wdt_info;
-static unsigned long open_check;
-static char expect_close;
-
-#if !defined(CONFIG_SMP)
-#define UBI32_WDT_LOCK(lock, flags) local_irq_save(flags)
-#define UBI32_WDT_UNLOCK(lock, flags) local_irq_restore(flags)
-#define UBI32_WDT_LOCK_CHECK()
-#else
-#define UBI32_WDT_LOCK(lock, flags) spin_lock_irqsave((lock), (flags));
-#define UBI32_WDT_UNLOCK(lock, flags) spin_unlock_irqrestore((lock), (flags));
-#define UBI32_WDT_LOCK_CHECK() BUG_ON(!spin_is_locked(&ubi32_wdt_spinlock));
-#endif
-
-/*
- * ubi32_wdt_remaining()
- * Return the approximate number of seconds remaining
- */
-static int ubi32_wdt_remaining(void)
-{
- int compare;
- int curr;
-
- UBI32_WDT_LOCK_CHECK();
-
- ubicom32_write_reg(&UBICOM32_IO_TIMER->tkey, TIMER_TKEYVAL);
- compare = ubicom32_read_reg(&UBICOM32_IO_TIMER->wdcom);
- curr = ubicom32_read_reg(&UBICOM32_IO_TIMER->mptval);
- ubicom32_write_reg(&UBICOM32_IO_TIMER->tkey, 0);
- return (compare - curr) / OSC1_FREQ;
-
-}
-
-/*
- * ubi32_wdt_keepalive()
- * Keep the Userspace Watchdog Alive
- *
- * The Userspace watchdog got a KeepAlive: schedule the next timeout.
- */
-static int ubi32_wdt_keepalive(void)
-{
- UBI32_WDT_LOCK_CHECK();
- ubicom32_write_reg(&UBICOM32_IO_TIMER->tkey, TIMER_TKEYVAL);
- ubicom32_write_reg(&UBICOM32_IO_TIMER->wdcom,
- ubicom32_read_reg(&UBICOM32_IO_TIMER->mptval)
- + WATCHDOG_SEC_TO_CYC(timeout));
- ubicom32_write_reg(&UBICOM32_IO_TIMER->tkey, 0);
- return 0;
-}
-
-/*
- * ubi32_wdt_stop()
- * Stop the on-chip Watchdog
- */
-static int ubi32_wdt_stop(void)
-{
- UBI32_WDT_LOCK_CHECK();
- ubicom32_write_reg(&UBICOM32_IO_TIMER->tkey, TIMER_TKEYVAL);
- ubicom32_write_reg(&UBICOM32_IO_TIMER->wdcfg, TIMER_WATCHDOG_DISABLE);
- ubicom32_write_reg(&UBICOM32_IO_TIMER->tkey, 0);
- return 0;
-}
-
-/*
- * ubi32_wdt_start()
- * Start the on-chip Watchdog
- */
-static int ubi32_wdt_start(void)
-{
- UBI32_WDT_LOCK_CHECK();
- ubicom32_write_reg(&UBICOM32_IO_TIMER->tkey, TIMER_TKEYVAL);
- ubicom32_write_reg(&UBICOM32_IO_TIMER->wdcom,
- ubicom32_read_reg(&UBICOM32_IO_TIMER->mptval)
- + WATCHDOG_SEC_TO_CYC(timeout));
- ubicom32_write_reg(&UBICOM32_IO_TIMER->wdcfg, ~TIMER_WATCHDOG_DISABLE);
- ubicom32_write_reg(&UBICOM32_IO_TIMER->tkey, 0);
- return 0;
-}
-
-/*
- * ubi32_wdt_running()
- * Return true if the watchdog is configured
- */
-static int ubi32_wdt_running(void)
-{
- int enabled;
-
- UBI32_WDT_LOCK_CHECK();
- ubicom32_write_reg(&UBICOM32_IO_TIMER->tkey, TIMER_TKEYVAL);
- enabled = ubicom32_read_reg(&UBICOM32_IO_TIMER->wdcfg) == ~TIMER_WATCHDOG_DISABLE;
- ubicom32_write_reg(&UBICOM32_IO_TIMER->tkey, 0);
- return enabled;
-}
-
-/*
- * ubi32_wdt_set_timeout()
- * Set the Userspace Watchdog timeout
- *
- * - @t: new timeout value (in seconds)
- */
-static int ubi32_wdt_set_timeout(unsigned long t)
-{
- UBI32_WDT_LOCK_CHECK();
-
- if (t > WATCHDOG_MAX_SEC) {
- printk(KERN_WARNING PFX "request to large: %ld [1-%d] sec)\n", t, WATCHDOG_MAX_SEC);
- return -EINVAL;
- }
-
- /*
- * If we are running, then reset the time value so
- * that the new value has an immediate effect.
- */
- timeout = t;
- if (ubi32_wdt_running()) {
- ubi32_wdt_keepalive();
- }
- return 0;
-}
-
-/*
- * ubi32_wdt_open()
- * Open the Device
- */
-static int ubi32_wdt_open(struct inode *inode, struct file *file)
-{
- unsigned long flags;
-
- if (test_and_set_bit(0, &open_check))
- return -EBUSY;
-
- if (nowayout)
- __module_get(THIS_MODULE);
-
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- ubi32_wdt_start();
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
-
- return nonseekable_open(inode, file);
-}
-
-/*
- * ubi32_wdt_close()
- * Close the Device
- */
-static int ubi32_wdt_release(struct inode *inode, struct file *file)
-{
- unsigned long flags;
-
- /*
- * If we don't expect a close, then the watchdog continues
- * even though the device is closed. The caller will have
- * a full timeout value to reopen the device and continue
- * stroking it.
- */
- if (expect_close != 42) {
- printk(KERN_CRIT PFX
- "Unexpected close, not stopping watchdog!\n");
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- ubi32_wdt_keepalive();
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- } else {
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- ubi32_wdt_stop();
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- }
-
- expect_close = 0;
- clear_bit(0, &open_check);
- return 0;
-}
-
-/*
- * ubi32_wdt_write()
- * Write to Device
- *
- * If the user writes nothing, nothing happens.
- * If the user writes a V, then we expect a close and allow a release.
- * If the user writes anything else, it is ignored.
- */
-static ssize_t ubi32_wdt_write(struct file *file, const char __user *data,
- size_t len, loff_t *ppos)
-{
- size_t i;
- unsigned long flags;
-
- /*
- * Every write resets the expect_close. The last write
- * must be a V to allow shutdown on close.
- */
- expect_close = 0;
-
- /*
- * Empty writes still ping.
- */
- if (!len) {
- goto ping;
- }
-
- /*
- * If nowayout is set, it does not matter if the caller
- * is trying to send the magic 'V' we will not allow a
- * close to stop us.
- */
- if (nowayout) {
- goto ping;
- }
-
- /*
- * See if the program wrote a 'V' and if so disable
- * the watchdog on release.
- */
- for (i = 0; i < len; i++) {
- char c;
- if (get_user(c, data + i)) {
- return -EFAULT;
- }
-
- if (c == 'V') {
- expect_close = 42;
- }
- }
-
-ping:
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- ubi32_wdt_keepalive();
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- return len;
-}
-
-/*
- * ubi32_wdt_ioctl()
- * Query the watchdog device.
- *
- * Query basic information from the device or ping it, as outlined by the
- * watchdog API.
- */
-static long ubi32_wdt_ioctl(struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- void __user *argp = (void __user *)arg;
- int __user *p = argp;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- if (copy_to_user(argp, &ubi32_wdt_info, sizeof(ubi32_wdt_info))) {
- return -EFAULT;
- }
- return 0;
-
- case WDIOC_GETSTATUS: {
- unsigned long flags;
- int running;
-
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- running = ubi32_wdt_running();
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- return running;
- }
-
- case WDIOC_GETBOOTSTATUS:
- return ubicom32_get_reset_reason();
-
- case WDIOC_SETOPTIONS: {
- unsigned long flags;
- int options, ret = -EINVAL;
-
- /*
- * The sample application does not pass a pointer
- * but directly passes a value of 1 or 2; however
- * all of the implementations (and thus probably
- * the real applications) pass a pointer to a value.
- *
- * It should be noted that WDIOC_SETOPTIONS is defined as
- * _IOR(WATCHDOG_IOCTL_BASE, 4, int), which means
- * that it should be an int and NOT a pointer.
- *
- * TODO: Examine this code for future chips.
- * TODO: Report the sample code defect.
- */
- if ((int)p < MIN_PROCESSOR_ADDRESS) {
- options = (int)p;
- } else {
- if (get_user(options, p))
- return -EFAULT;
- }
-
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- if (options & WDIOS_DISABLECARD) {
- ubi32_wdt_stop();
- ret = 0;
- }
- if (options & WDIOS_ENABLECARD) {
- ubi32_wdt_start();
- ret = 0;
- }
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- return ret;
- }
-
- case WDIOC_KEEPALIVE: {
- unsigned long flags;
-
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- ubi32_wdt_keepalive();
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- return 0;
- }
-
- case WDIOC_SETTIMEOUT: {
- int new_timeout;
- unsigned long flags;
- int ret = 0;
-
- if (get_user(new_timeout, p))
- return -EFAULT;
-
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- ret = ubi32_wdt_set_timeout(new_timeout);
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- return ret;
-
- }
-
- case WDIOC_GETTIMEOUT:
- return put_user(timeout, p);
-
- case WDIOC_GETTIMELEFT: {
- unsigned long flags;
- int remaining = 0;
-
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- remaining = ubi32_wdt_remaining();
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- return put_user(remaining, p);
- }
-
- default:
- return -ENOTTY;
- }
-}
-
-/*
- * ubi32_wdt_notify_sys()
- * Notification callback function for system events.
- *
- * Turn off the watchdog during a SYS_DOWN or SYS_HALT.
- */
-static int ubi32_wdt_notify_sys(struct notifier_block *this,
- unsigned long code, void *unused)
-{
- if (code == SYS_DOWN || code == SYS_HALT) {
- unsigned long flags;
-
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- ubi32_wdt_stop();
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- }
-
- return NOTIFY_DONE;
-}
-
-#ifdef CONFIG_PM
-static int state_before_suspend;
-
-/*
- * ubi32_wdt_suspend()
- * suspend the watchdog
- *
- * Remember if the watchdog was running and stop it.
- */
-static int ubi32_wdt_suspend(struct platform_device *pdev, pm_message_t state)
-{
- unsigned long flags;
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- state_before_suspend = ubi32_wdt_running();
- ubi32_wdt_stop();
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
-
- return 0;
-}
-
-/*
- * ubi32_wdt_resume()
- * Resume the watchdog
- *
- * If the watchdog was running, turn it back on.
- */
-static int ubi32_wdt_resume(struct platform_device *pdev)
-{
- if (state_before_suspend) {
- unsigned long flags;
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- ubi32_wdt_set_timeout(timeout);
- ubi32_wdt_start();
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- }
-
- return 0;
-}
-#else
-# define ubi32_wdt_suspend NULL
-# define ubi32_wdt_resume NULL
-#endif
-
-static const struct file_operations ubi32_wdt_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = ubi32_wdt_write,
- .unlocked_ioctl = ubi32_wdt_ioctl,
- .open = ubi32_wdt_open,
- .release = ubi32_wdt_release,
-};
-
-static struct miscdevice ubi32_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &ubi32_wdt_fops,
-};
-
-static struct watchdog_info ubi32_wdt_info = {
- .identity = "Ubicom32 Watchdog",
- .options = WDIOF_SETTIMEOUT |
- WDIOF_KEEPALIVEPING |
- WDIOF_MAGICCLOSE,
-};
-
-static struct notifier_block ubi32_wdt_notifier = {
- .notifier_call = ubi32_wdt_notify_sys,
-};
-
-/*
- * ubi32_wdt_probe()
- * Probe/register the watchdog module
- *
- * Registers the misc device and notifier handler. Actual device
- * initialization is handled by ubi32_wdt_open().
- */
-static int __devinit ubi32_wdt_probe(struct platform_device *pdev)
-{
- int ret;
-
- ret = register_reboot_notifier(&ubi32_wdt_notifier);
- if (ret) {
- printk(KERN_ERR PFX
- "cannot register reboot notifier (err=%d)\n", ret);
- return ret;
- }
-
- ret = misc_register(&ubi32_wdt_miscdev);
- if (ret) {
- printk(KERN_ERR PFX
- "cannot register miscdev on minor=%d (err=%d)\n",
- WATCHDOG_MINOR, ret);
- unregister_reboot_notifier(&ubi32_wdt_notifier);
- return ret;
- }
-
- printk(KERN_INFO PFX "initialized: timeout=%d sec (nowayout=%d)\n",
- timeout, nowayout);
-
- return 0;
-}
-
-/*
- * ubi32_wdt_remove()
- * Uninstall the module
- *
- * Unregisters the misc device and notifier handler. Actual device
- * deinitialization is handled by ubi32_wdt_close().
- */
-static int __devexit ubi32_wdt_remove(struct platform_device *pdev)
-{
- misc_deregister(&ubi32_wdt_miscdev);
- unregister_reboot_notifier(&ubi32_wdt_notifier);
- return 0;
-}
-
-static struct platform_device *ubi32_wdt_device;
-
-static struct platform_driver ubi32_wdt_driver = {
- .probe = ubi32_wdt_probe,
- .remove = __devexit_p(ubi32_wdt_remove),
- .suspend = ubi32_wdt_suspend,
- .resume = ubi32_wdt_resume,
- .driver = {
- .name = WATCHDOG_NAME,
- .owner = THIS_MODULE,
- },
-};
-
-/*
- * ubi32_wdt_init()
- * Initialize the watchdog.
- *
- * Checks the module params and registers the platform device & driver.
- * Real work is in the platform probe function.
- */
-static int __init ubi32_wdt_init(void)
-{
- unsigned long flags;
- int ret;
-
- /*
- * Check that the timeout value is within range
- */
- spin_lock_irqsave(&ubi32_wdt_spinlock, flags);
- ret = ubi32_wdt_set_timeout(timeout);
- spin_unlock_irqrestore(&ubi32_wdt_spinlock, flags);
- if (ret) {
- return ret;
- }
-
- /*
- * Since this is an on-chip device and needs no board-specific
- * resources, we'll handle all the platform device stuff here.
- */
- ret = platform_driver_register(&ubi32_wdt_driver);
- if (ret) {
- printk(KERN_ERR PFX "unable to register driver\n");
- return ret;
- }
-
- ubi32_wdt_device = platform_device_register_simple(WATCHDOG_NAME, -1, NULL, 0);
- if (IS_ERR(ubi32_wdt_device)) {
- printk(KERN_ERR PFX "unable to register device\n");
- platform_driver_unregister(&ubi32_wdt_driver);
- return PTR_ERR(ubi32_wdt_device);
- }
-
- return 0;
-}
-
-/*
- * ubi32_wdt_exit()
- * Deinitialize module
- *
- * Back out the platform device & driver steps. Real work is in the
- * platform remove function.
- */
-static void __exit ubi32_wdt_exit(void)
-{
- platform_device_unregister(ubi32_wdt_device);
- platform_driver_unregister(&ubi32_wdt_driver);
-}
-
-module_init(ubi32_wdt_init);
-module_exit(ubi32_wdt_exit);
-
-MODULE_AUTHOR("Sol Kavy<sol@ubicom.com>");
-MODULE_DESCRIPTION("Ubicom32 Watchdog Device Driver");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
-
-module_param(timeout, uint, 0);
-MODULE_PARM_DESC(timeout,
- "Watchdog timeout in seconds. (1<=timeout<=((2^32)/SCLK), default="
- __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
-
-module_param(nowayout, int, 0);
-MODULE_PARM_DESC(nowayout,
- "Watchdog cannot be stopped once started (default="
- __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
projects / openwrt / svn-archive / archive.git / blobdiff