diff options
Diffstat (limited to 'drivers/char/watchdog/mpc8xx_wdt.c')
-rw-r--r-- | drivers/char/watchdog/mpc8xx_wdt.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/drivers/char/watchdog/mpc8xx_wdt.c b/drivers/char/watchdog/mpc8xx_wdt.c new file mode 100644 index 000000000000..56d62ba7c6ce --- /dev/null +++ b/drivers/char/watchdog/mpc8xx_wdt.c @@ -0,0 +1,164 @@ +/* + * 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/config.h> +#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 <syslib/m8xx_wdt.h> + +static unsigned long wdt_opened; +static int wdt_status; + +static void mpc8xx_wdt_handler_disable(void) +{ + volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR; + + imap->im_sit.sit_piscr &= ~(PISCR_PIE | PISCR_PTE); + + printk(KERN_NOTICE "mpc8xx_wdt: keep-alive handler deactivated\n"); +} + +static void mpc8xx_wdt_handler_enable(void) +{ + volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR; + + imap->im_sit.sit_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 0; +} + +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 (ppos != &file->f_pos) + return -ESPIPE; + + 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 -ENOIOCTLCMD; + } + + return 0; +} + +static 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); |