projects / mirror_ubuntu-bionic-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* |
| 2 | * mpc8xx_wdt.c - MPC8xx watchdog userspace interface | |
| 3 | * | |
| 4 | * Author: Florian Schirmer <jolt@tuxbox.org> | |
| 5 | * | |
| 6 | * 2002 (c) Florian Schirmer <jolt@tuxbox.org> This file is licensed under | |
| 7 | * the terms of the GNU General Public License version 2. This program | |
| 8 | * is licensed "as is" without any warranty of any kind, whether express | |
| 9 | * or implied. | |
| 10 | */ | |
| 11 | ||
| 12 | #include <linux/config.h> | |
| 13 | #include <linux/fs.h> | |
| 14 | #include <linux/init.h> | |
| 15 | #include <linux/kernel.h> | |
| 16 | #include <linux/miscdevice.h> | |
| 17 | #include <linux/module.h> | |
| 18 | #include <linux/watchdog.h> | |
| 19 | #include <asm/8xx_immap.h> | |
| 20 | #include <asm/uaccess.h> | |
| 21 | #include <syslib/m8xx_wdt.h> | |
| 22 | ||
| 23 | static unsigned long wdt_opened; | |
| 24 | static int wdt_status; | |
| 25 | ||
| 26 | static void mpc8xx_wdt_handler_disable(void) | |
| 27 | { | |
| 28 | volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR; | |
| 29 | ||
| 30 | imap->im_sit.sit_piscr &= ~(PISCR_PIE | PISCR_PTE); | |
| 31 | ||
| 32 | printk(KERN_NOTICE "mpc8xx_wdt: keep-alive handler deactivated\n"); | |
| 33 | } | |
| 34 | ||
| 35 | static void mpc8xx_wdt_handler_enable(void) | |
| 36 | { | |
| 37 | volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR; | |
| 38 | ||
| 39 | imap->im_sit.sit_piscr |= PISCR_PIE | PISCR_PTE; | |
| 40 | ||
| 41 | printk(KERN_NOTICE "mpc8xx_wdt: keep-alive handler activated\n"); | |
| 42 | } | |
| 43 | ||
| 44 | static int mpc8xx_wdt_open(struct inode *inode, struct file *file) | |
| 45 | { | |
| 46 | if (test_and_set_bit(0, &wdt_opened)) | |
| 47 | return -EBUSY; | |
| 48 | ||
| 49 | m8xx_wdt_reset(); | |
| 50 | mpc8xx_wdt_handler_disable(); | |
| 51 | ||
| 52 | return 0; | |
| 53 | } | |
| 54 | ||
| 55 | static int mpc8xx_wdt_release(struct inode *inode, struct file *file) | |
| 56 | { | |
| 57 | m8xx_wdt_reset(); | |
| 58 | ||
| 59 | #if !defined(CONFIG_WATCHDOG_NOWAYOUT) | |
| 60 | mpc8xx_wdt_handler_enable(); | |
| 61 | #endif | |
| 62 | ||
| 63 | clear_bit(0, &wdt_opened); | |
| 64 | ||
| 65 | return 0; | |
| 66 | } | |
| 67 | ||
| 68 | static ssize_t mpc8xx_wdt_write(struct file *file, const char *data, size_t len, | |
| 69 | loff_t * ppos) | |
| 70 | { | |
| 71 | if (ppos != &file->f_pos) | |
| 72 | return -ESPIPE; | |
| 73 | ||
| 74 | if (len) | |
| 75 | m8xx_wdt_reset(); | |
| 76 | ||
| 77 | return len; | |
| 78 | } | |
| 79 | ||
| 80 | static int mpc8xx_wdt_ioctl(struct inode *inode, struct file *file, | |
| 81 | unsigned int cmd, unsigned long arg) | |
| 82 | { | |
| 83 | int timeout; | |
| 84 | static struct watchdog_info info = { | |
| 85 | .options = WDIOF_KEEPALIVEPING, | |
| 86 | .firmware_version = 0, | |
| 87 | .identity = "MPC8xx watchdog", | |
| 88 | }; | |
| 89 | ||
| 90 | switch (cmd) { | |
| 91 | case WDIOC_GETSUPPORT: | |
| 92 | if (copy_to_user((void *)arg, &info, sizeof(info))) | |
| 93 | return -EFAULT; | |
| 94 | break; | |
| 95 | ||
| 96 | case WDIOC_GETSTATUS: | |
| 97 | case WDIOC_GETBOOTSTATUS: | |
| 98 | if (put_user(wdt_status, (int *)arg)) | |
| 99 | return -EFAULT; | |
| 100 | wdt_status &= ~WDIOF_KEEPALIVEPING; | |
| 101 | break; | |
| 102 | ||
| 103 | case WDIOC_GETTEMP: | |
| 104 | return -EOPNOTSUPP; | |
| 105 | ||
| 106 | case WDIOC_SETOPTIONS: | |
| 107 | return -EOPNOTSUPP; | |
| 108 | ||
| 109 | case WDIOC_KEEPALIVE: | |
| 110 | m8xx_wdt_reset(); | |
| 111 | wdt_status |= WDIOF_KEEPALIVEPING; | |
| 112 | break; | |
| 113 | ||
| 114 | case WDIOC_SETTIMEOUT: | |
| 115 | return -EOPNOTSUPP; | |
| 116 | ||
| 117 | case WDIOC_GETTIMEOUT: | |
| 118 | timeout = m8xx_wdt_get_timeout(); | |
| 119 | if (put_user(timeout, (int *)arg)) | |
| 120 | return -EFAULT; | |
| 121 | break; | |
| 122 | ||
| 123 | default: | |
| 124 | return -ENOIOCTLCMD; | |
| 125 | } | |
| 126 | ||
| 127 | return 0; | |
| 128 | } | |
| 129 | ||
| 130 | static struct file_operations mpc8xx_wdt_fops = { | |
| 131 | .owner = THIS_MODULE, | |
| 132 | .llseek = no_llseek, | |
| 133 | .write = mpc8xx_wdt_write, | |
| 134 | .ioctl = mpc8xx_wdt_ioctl, | |
| 135 | .open = mpc8xx_wdt_open, | |
| 136 | .release = mpc8xx_wdt_release, | |
| 137 | }; | |
| 138 | ||
| 139 | static struct miscdevice mpc8xx_wdt_miscdev = { | |
| 140 | .minor = WATCHDOG_MINOR, | |
| 141 | .name = "watchdog", | |
| 142 | .fops = &mpc8xx_wdt_fops, | |
| 143 | }; | |
| 144 | ||
| 145 | static int __init mpc8xx_wdt_init(void) | |
| 146 | { | |
| 147 | return misc_register(&mpc8xx_wdt_miscdev); | |
| 148 | } | |
| 149 | ||
| 150 | static void __exit mpc8xx_wdt_exit(void) | |
| 151 | { | |
| 152 | misc_deregister(&mpc8xx_wdt_miscdev); | |
| 153 | ||
| 154 | m8xx_wdt_reset(); | |
| 155 | mpc8xx_wdt_handler_enable(); | |
| 156 | } | |
| 157 | ||
| 158 | module_init(mpc8xx_wdt_init); | |
| 159 | module_exit(mpc8xx_wdt_exit); | |
| 160 | ||
| 161 | MODULE_AUTHOR("Florian Schirmer <jolt@tuxbox.org>"); | |
| 162 | MODULE_DESCRIPTION("MPC8xx watchdog driver"); | |
| 163 | MODULE_LICENSE("GPL"); | |
| 164 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |