diff options
Diffstat (limited to 'target/linux/ar7/files/drivers/char/watchdog/ar7_wdt.c')
-rw-r--r-- | target/linux/ar7/files/drivers/char/watchdog/ar7_wdt.c | 349 |
1 files changed, 0 insertions, 349 deletions
diff --git a/target/linux/ar7/files/drivers/char/watchdog/ar7_wdt.c b/target/linux/ar7/files/drivers/char/watchdog/ar7_wdt.c deleted file mode 100644 index 97cd8105a..000000000 --- a/target/linux/ar7/files/drivers/char/watchdog/ar7_wdt.c +++ /dev/null @@ -1,349 +0,0 @@ -/* - * drivers/watchdog/ar7_wdt.c - * - * Copyright (C) 2007 Nicolas Thill <nico@openwrt.org> - * Copyright (c) 2005 Enrik Berkhan <Enrik.Berkhan@akk.org> - * - * Some code taken from: - * National Semiconductor SCx200 Watchdog support - * Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com> - * - * 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. - * - * This program 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 this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#include <linux/module.h> -#include <linux/moduleparam.h> -#include <linux/errno.h> -#include <linux/init.h> -#include <linux/miscdevice.h> -#include <linux/watchdog.h> -#include <linux/notifier.h> -#include <linux/reboot.h> -#include <linux/fs.h> -#include <linux/ioport.h> -#include <linux/io.h> -#include <linux/uaccess.h> - -#include <asm/addrspace.h> -#include <asm/ar7/ar7.h> - -#define DRVNAME "ar7_wdt" -#define LONGNAME "TI AR7 Watchdog Timer" - -MODULE_AUTHOR("Nicolas Thill <nico@openwrt.org>"); -MODULE_DESCRIPTION(LONGNAME); -MODULE_LICENSE("GPL"); -MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); - -static int margin = 60; -module_param(margin, int, 0); -MODULE_PARM_DESC(margin, "Watchdog margin in seconds"); - -static int nowayout = WATCHDOG_NOWAYOUT; -module_param(nowayout, int, 0); -MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close"); - -#define READ_REG(x) readl((void __iomem *)&(x)) -#define WRITE_REG(x, v) writel((v), (void __iomem *)&(x)) - -struct ar7_wdt { - u32 kick_lock; - u32 kick; - u32 change_lock; - u32 change; - u32 disable_lock; - u32 disable; - u32 prescale_lock; - u32 prescale; -}; - -static struct semaphore open_semaphore; -static unsigned expect_close; - -/* XXX currently fixed, allows max margin ~68.72 secs */ -#define prescale_value 0xffff - -/* Offset of the WDT registers */ -static unsigned long ar7_regs_wdt; -/* Pointer to the remapped WDT IO space */ -static struct ar7_wdt *ar7_wdt; -static void ar7_wdt_get_regs(void) -{ - u16 chip_id = ar7_chip_id(); - switch (chip_id) { - case AR7_CHIP_7100: - case AR7_CHIP_7200: - ar7_regs_wdt = AR7_REGS_WDT; - break; - default: - ar7_regs_wdt = UR8_REGS_WDT; - break; - } -} - - -static void ar7_wdt_kick(u32 value) -{ - WRITE_REG(ar7_wdt->kick_lock, 0x5555); - if ((READ_REG(ar7_wdt->kick_lock) & 3) == 1) { - WRITE_REG(ar7_wdt->kick_lock, 0xaaaa); - if ((READ_REG(ar7_wdt->kick_lock) & 3) == 3) { - WRITE_REG(ar7_wdt->kick, value); - return; - } - } - printk(KERN_ERR DRVNAME ": failed to unlock WDT kick reg\n"); -} - -static void ar7_wdt_prescale(u32 value) -{ - WRITE_REG(ar7_wdt->prescale_lock, 0x5a5a); - if ((READ_REG(ar7_wdt->prescale_lock) & 3) == 1) { - WRITE_REG(ar7_wdt->prescale_lock, 0xa5a5); - if ((READ_REG(ar7_wdt->prescale_lock) & 3) == 3) { - WRITE_REG(ar7_wdt->prescale, value); - return; - } - } - printk(KERN_ERR DRVNAME ": failed to unlock WDT prescale reg\n"); -} - -static void ar7_wdt_change(u32 value) -{ - WRITE_REG(ar7_wdt->change_lock, 0x6666); - if ((READ_REG(ar7_wdt->change_lock) & 3) == 1) { - WRITE_REG(ar7_wdt->change_lock, 0xbbbb); - if ((READ_REG(ar7_wdt->change_lock) & 3) == 3) { - WRITE_REG(ar7_wdt->change, value); - return; - } - } - printk(KERN_ERR DRVNAME ": failed to unlock WDT change reg\n"); -} - -static void ar7_wdt_disable(u32 value) -{ - WRITE_REG(ar7_wdt->disable_lock, 0x7777); - if ((READ_REG(ar7_wdt->disable_lock) & 3) == 1) { - WRITE_REG(ar7_wdt->disable_lock, 0xcccc); - if ((READ_REG(ar7_wdt->disable_lock) & 3) == 2) { - WRITE_REG(ar7_wdt->disable_lock, 0xdddd); - if ((READ_REG(ar7_wdt->disable_lock) & 3) == 3) { - WRITE_REG(ar7_wdt->disable, value); - return; - } - } - } - printk(KERN_ERR DRVNAME ": failed to unlock WDT disable reg\n"); -} - -static void ar7_wdt_update_margin(int new_margin) -{ - u32 change; - - change = new_margin * (ar7_vbus_freq() / prescale_value); - if (change < 1) change = 1; - if (change > 0xffff) change = 0xffff; - ar7_wdt_change(change); - margin = change * prescale_value / ar7_vbus_freq(); - printk(KERN_INFO DRVNAME - ": timer margin %d seconds (prescale %d, change %d, freq %d)\n", - margin, prescale_value, change, ar7_vbus_freq()); -} - -static void ar7_wdt_enable_wdt(void) -{ - printk(KERN_DEBUG DRVNAME ": enabling watchdog timer\n"); - ar7_wdt_disable(1); - ar7_wdt_kick(1); -} - -static void ar7_wdt_disable_wdt(void) -{ - printk(KERN_DEBUG DRVNAME ": disabling watchdog timer\n"); - ar7_wdt_disable(0); -} - -static int ar7_wdt_open(struct inode *inode, struct file *file) -{ - /* only allow one at a time */ - if (down_trylock(&open_semaphore)) - return -EBUSY; - ar7_wdt_enable_wdt(); - expect_close = 0; - - return nonseekable_open(inode, file); -} - -static int ar7_wdt_release(struct inode *inode, struct file *file) -{ - if (!expect_close) - printk(KERN_WARNING DRVNAME - ": watchdog device closed unexpectedly," - "will not disable the watchdog timer\n"); - else if (!nowayout) - ar7_wdt_disable_wdt(); - - up(&open_semaphore); - - return 0; -} - -static int ar7_wdt_notify_sys(struct notifier_block *this, - unsigned long code, void *unused) -{ - if (code == SYS_HALT || code == SYS_POWER_OFF) - if (!nowayout) - ar7_wdt_disable_wdt(); - - return NOTIFY_DONE; -} - -static struct notifier_block ar7_wdt_notifier = { - .notifier_call = ar7_wdt_notify_sys -}; - -static ssize_t ar7_wdt_write(struct file *file, const char *data, - size_t len, loff_t *ppos) -{ - /* check for a magic close character */ - if (len) { - size_t i; - - ar7_wdt_kick(1); - - expect_close = 0; - for (i = 0; i < len; ++i) { - char c; - if (get_user(c, data+i)) - return -EFAULT; - if (c == 'V') - expect_close = 1; - } - - } - return len; -} - -static int ar7_wdt_ioctl(struct inode *inode, struct file *file, - unsigned int cmd, unsigned long arg) -{ - static struct watchdog_info ident = { - .identity = LONGNAME, - .firmware_version = 1, - .options = (WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING), - }; - int new_margin; - - switch (cmd) { - default: - return -ENOTTY; - case WDIOC_GETSUPPORT: - if (copy_to_user((struct watchdog_info *)arg, &ident, - sizeof(ident))) - return -EFAULT; - return 0; - case WDIOC_GETSTATUS: - case WDIOC_GETBOOTSTATUS: - if (put_user(0, (int *)arg)) - return -EFAULT; - return 0; - case WDIOC_KEEPALIVE: - ar7_wdt_kick(1); - return 0; - case WDIOC_SETTIMEOUT: - if (get_user(new_margin, (int *)arg)) - return -EFAULT; - if (new_margin < 1) - return -EINVAL; - - ar7_wdt_update_margin(new_margin); - ar7_wdt_kick(1); - - case WDIOC_GETTIMEOUT: - if (put_user(margin, (int *)arg)) - return -EFAULT; - return 0; - } -} - -static struct file_operations ar7_wdt_fops = { - .owner = THIS_MODULE, - .write = ar7_wdt_write, - .ioctl = ar7_wdt_ioctl, - .open = ar7_wdt_open, - .release = ar7_wdt_release, -}; - -static struct miscdevice ar7_wdt_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &ar7_wdt_fops, -}; - -static int __init ar7_wdt_init(void) -{ - int rc; - - ar7_wdt_get_regs(); - - if (!request_mem_region(ar7_regs_wdt, sizeof(struct ar7_wdt), - LONGNAME)) { - printk(KERN_WARNING DRVNAME ": watchdog I/O region busy\n"); - return -EBUSY; - } - - ar7_wdt = (struct ar7_wdt *) - ioremap(ar7_regs_wdt, sizeof(struct ar7_wdt)); - - ar7_wdt_disable_wdt(); - ar7_wdt_prescale(prescale_value); - ar7_wdt_update_margin(margin); - - sema_init(&open_semaphore, 1); - - rc = register_reboot_notifier(&ar7_wdt_notifier); - if (rc) { - printk(KERN_ERR DRVNAME - ": unable to register reboot notifier\n"); - goto out_alloc; - } - - rc = misc_register(&ar7_wdt_miscdev); - if (rc) { - printk(KERN_ERR DRVNAME ": unable to register misc device\n"); - goto out_register; - } - goto out; - -out_register: - unregister_reboot_notifier(&ar7_wdt_notifier); -out_alloc: - iounmap(ar7_wdt); - release_mem_region(ar7_regs_wdt, sizeof(struct ar7_wdt)); -out: - return rc; -} - -static void __exit ar7_wdt_cleanup(void) -{ - misc_deregister(&ar7_wdt_miscdev); - unregister_reboot_notifier(&ar7_wdt_notifier); - iounmap(ar7_wdt); - release_mem_region(ar7_regs_wdt, sizeof(struct ar7_wdt)); -} - -module_init(ar7_wdt_init); -module_exit(ar7_wdt_cleanup); |