diff options
Diffstat (limited to 'target/linux/ifxmips/files/drivers/watchdog/ifxmips.c')
| -rw-r--r-- | target/linux/ifxmips/files/drivers/watchdog/ifxmips.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/target/linux/ifxmips/files/drivers/watchdog/ifxmips.c b/target/linux/ifxmips/files/drivers/watchdog/ifxmips.c new file mode 100644 index 000000000..b06307cb7 --- /dev/null +++ b/target/linux/ifxmips/files/drivers/watchdog/ifxmips.c @@ -0,0 +1,195 @@ +/* + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Copyright (C) 2008 John Crispin <blogic@openwrt.org> + * Based on EP93xx wdt driver + */ + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/miscdevice.h> +#include <linux/miscdevice.h> +#include <linux/watchdog.h> +#include <linux/platform_device.h> +#include <linux/uaccess.h> + +#include <ifxmips.h> +#include <ifxmips_cgu.h> + +#define IFXMIPS_WDT_PW1 0x00BE0000 +#define IFXMIPS_WDT_PW2 0x00DC0000 + +#ifndef CONFIG_WATCHDOG_NOWAYOUT +static int wdt_ok_to_close; +#endif + +static int wdt_timeout = 30; + +int ifxmips_wdt_enable(unsigned int timeout) +{ + u32 fpi; + fpi = cgu_get_io_region_clock(); + ifxmips_w32(IFXMIPS_WDT_PW1, IFXMIPS_BIU_WDT_CR); + ifxmips_w32(IFXMIPS_WDT_PW2 | + (0x3 << 26) | /* PWL */ + (0x3 << 24) | /* CLKDIV */ + (0x1 << 31) | /* enable */ + ((timeout * (fpi / 0x40000)) + 0x1000), /* reload */ + IFXMIPS_BIU_WDT_CR); + return 0; +} + +void ifxmips_wdt_disable(void) +{ +#ifndef CONFIG_WATCHDOG_NOWAYOUT + wdt_ok_to_close = 0; +#endif + ifxmips_w32(IFXMIPS_WDT_PW1, IFXMIPS_BIU_WDT_CR); + ifxmips_w32(IFXMIPS_WDT_PW2, IFXMIPS_BIU_WDT_CR); +} + +static ssize_t ifxmips_wdt_write(struct file *file, const char __user *data, + size_t len, loff_t *ppos) +{ + size_t i; + + if (!len) + return 0; + +#ifndef CONFIG_WATCHDOG_NOWAYOUT + for (i = 0; i != len; i++) { + char c; + if (get_user(c, data + i)) + return -EFAULT; + if (c == 'V') + wdt_ok_to_close = 1; + } +#endif + ifxmips_wdt_enable(wdt_timeout); + return len; +} + +static struct watchdog_info ident = { + .options = WDIOF_MAGICCLOSE, + .identity = "ifxmips Watchdog", +}; + +static int ifxmips_wdt_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, unsigned long arg) +{ + int ret = -ENOTTY; + + switch (cmd) { + case WDIOC_GETSUPPORT: + ret = copy_to_user((struct watchdog_info __user *)arg, &ident, + sizeof(ident)) ? -EFAULT : 0; + break; + + case WDIOC_GETTIMEOUT: + ret = put_user(wdt_timeout, (int __user *)arg); + break; + + case WDIOC_SETTIMEOUT: + ret = get_user(wdt_timeout, (int __user *)arg); + break; + + case WDIOC_KEEPALIVE: + ifxmips_wdt_enable(wdt_timeout); + ret = 0; + break; + } + return ret; +} + +static int ifxmips_wdt_open(struct inode *inode, struct file *file) +{ + ifxmips_wdt_enable(wdt_timeout); + return nonseekable_open(inode, file); +} + +static int ifxmips_wdt_release(struct inode *inode, struct file *file) +{ +#ifndef CONFIG_WATCHDOG_NOWAYOUT + if (wdt_ok_to_close) + ifxmips_wdt_disable(); + else +#endif + printk(KERN_ERR "ifxmips_wdt: watchdog closed without warning," + " rebooting system\n"); + return 0; +} + +static const struct file_operations ifxmips_wdt_fops = { + .owner = THIS_MODULE, + .write = ifxmips_wdt_write, + .ioctl = ifxmips_wdt_ioctl, + .open = ifxmips_wdt_open, + .release = ifxmips_wdt_release, +}; + +static struct miscdevice ifxmips_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &ifxmips_wdt_fops, +}; + +static int ifxmips_wdt_probe(struct platform_device *dev) +{ + int err; + err = misc_register(&ifxmips_wdt_miscdev); + if (err) + printk(KERN_INFO "ifxmips_wdt: error creating device\n"); + else + printk(KERN_INFO "ifxmips_wdt: loaded\n"); + return err; +} + +static int ifxmips_wdt_remove(struct platform_device *dev) +{ + ifxmips_wdt_disable(); + misc_deregister(&ifxmips_wdt_miscdev); + return 0; +} + + +static struct platform_driver ifxmips_wdt_driver = { + .probe = ifxmips_wdt_probe, + .remove = ifxmips_wdt_remove, + .driver = { + .name = "ifxmips_wdt", + .owner = THIS_MODULE, + }, +}; + +static int __init init_ifxmips_wdt(void) +{ + int ret = platform_driver_register(&ifxmips_wdt_driver); + if (ret) + printk(KERN_INFO "ifxmips_wdt: error registering platfom driver!"); + return ret; +} + +static void __exit exit_ifxmips_wdt(void) +{ + platform_driver_unregister(&ifxmips_wdt_driver); +} + +module_init(init_ifxmips_wdt); +module_exit(exit_ifxmips_wdt); + +MODULE_AUTHOR("John Crispin <blogic@openwrt.org>"); +MODULE_DESCRIPTION("ifxmips Watchdog"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |