/* * mpc8xx_wdt.c - MPC8xx watchdog userspace interface * * Author: Florian Schirmer <jolt@tuxbox.org> * * 2002 (c) Florian Schirmer <jolt@tuxbox.org> This file is licensed under * the terms of the GNU General Public License version 2. This program * is licensed "as is" without any warranty of any kind, whether express * or implied. */ #include <linux/fs.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/miscdevice.h> #include <linux/module.h> #include <linux/watchdog.h> #include <asm/8xx_immap.h> #include <asm/uaccess.h> #include <asm/io.h> #include <syslib/m8xx_wdt.h> static unsigned long wdt_opened; static int wdt_status; static void mpc8xx_wdt_handler_disable(void) { volatile uint __iomem *piscr; piscr = (uint *)&((immap_t*)IMAP_ADDR)->im_sit.sit_piscr; if (!m8xx_has_internal_rtc) m8xx_wdt_stop_timer(); else out_be32(piscr, in_be32(piscr) & ~(PISCR_PIE | PISCR_PTE)); printk(KERN_NOTICE "mpc8xx_wdt: keep-alive handler deactivated\n"); } static void mpc8xx_wdt_handler_enable(void) { volatile uint __iomem *piscr; piscr = (uint *)&((immap_t*)IMAP_ADDR)->im_sit.sit_piscr; if (!m8xx_has_internal_rtc) m8xx_wdt_install_timer(); else out_be32(piscr, in_be32(piscr) | PISCR_PIE | PISCR_PTE); printk(KERN_NOTICE "mpc8xx_wdt: keep-alive handler activated\n"); } static int mpc8xx_wdt_open(struct inode *inode, struct file *file) { if (test_and_set_bit(0, &wdt_opened)) return -EBUSY; m8xx_wdt_reset(); mpc8xx_wdt_handler_disable(); return nonseekable_open(inode, file); } static int mpc8xx_wdt_release(struct inode *inode, struct file *file) { m8xx_wdt_reset(); #if !defined(CONFIG_WATCHDOG_NOWAYOUT) mpc8xx_wdt_handler_enable(); #endif clear_bit(0, &wdt_opened); return 0; } static ssize_t mpc8xx_wdt_write(struct file *file, const char *data, size_t len, loff_t * ppos) { if (len) m8xx_wdt_reset(); return len; } static int mpc8xx_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) { int timeout; static struct watchdog_info info = { .options = WDIOF_KEEPALIVEPING, .firmware_version = 0, .identity = "MPC8xx watchdog", }; switch (cmd) { case WDIOC_GETSUPPORT: if (copy_to_user((void *)arg, &info, sizeof(info))) return -EFAULT; break; case WDIOC_GETSTATUS: case WDIOC_GETBOOTSTATUS: if (put_user(wdt_status, (int *)arg)) return -EFAULT; wdt_status &= ~WDIOF_KEEPALIVEPING; break; case WDIOC_GETTEMP: return -EOPNOTSUPP; case WDIOC_SETOPTIONS: return -EOPNOTSUPP; case WDIOC_KEEPALIVE: m8xx_wdt_reset(); wdt_status |= WDIOF_KEEPALIVEPING; break; case WDIOC_SETTIMEOUT: return -EOPNOTSUPP; case WDIOC_GETTIMEOUT: timeout = m8xx_wdt_get_timeout(); if (put_user(timeout, (int *)arg)) return -EFAULT; break; default: return -ENOTTY; } return 0; } static const struct file_operations mpc8xx_wdt_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .write = mpc8xx_wdt_write, .ioctl = mpc8xx_wdt_ioctl, .open = mpc8xx_wdt_open, .release = mpc8xx_wdt_release, }; static struct miscdevice mpc8xx_wdt_miscdev = { .minor = WATCHDOG_MINOR, .name = "watchdog", .fops = &mpc8xx_wdt_fops, }; static int __init mpc8xx_wdt_init(void) { return misc_register(&mpc8xx_wdt_miscdev); } static void __exit mpc8xx_wdt_exit(void) { misc_deregister(&mpc8xx_wdt_miscdev); m8xx_wdt_reset(); mpc8xx_wdt_handler_enable(); } module_init(mpc8xx_wdt_init); module_exit(mpc8xx_wdt_exit); MODULE_AUTHOR("Florian Schirmer <jolt@tuxbox.org>"); MODULE_DESCRIPTION("MPC8xx watchdog driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);