From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/watchdog/mixcomwd.c | 317 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 317 insertions(+) create mode 100644 drivers/watchdog/mixcomwd.c (limited to 'drivers/watchdog/mixcomwd.c') diff --git a/drivers/watchdog/mixcomwd.c b/drivers/watchdog/mixcomwd.c new file mode 100644 index 000000000..be86ea359 --- /dev/null +++ b/drivers/watchdog/mixcomwd.c @@ -0,0 +1,317 @@ +/* + * MixCom Watchdog: A Simple Hardware Watchdog Device + * Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis + * + * Author: Gergely Madarasz + * + * Copyright (c) 1999 ITConsult-Pro Co. + * + * 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. + * + * Version 0.1 (99/04/15): + * - first version + * + * Version 0.2 (99/06/16): + * - added kernel timer watchdog ping after close + * since the hardware does not support watchdog shutdown + * + * Version 0.3 (99/06/21): + * - added WDIOC_GETSTATUS and WDIOC_GETSUPPORT ioctl calls + * + * Version 0.3.1 (99/06/22): + * - allow module removal while internal timer is active, + * print warning about probable reset + * + * Version 0.4 (99/11/15): + * - support for one more type board + * + * Version 0.5 (2001/12/14) Matt Domsch + * - added nowayout module option to override + * CONFIG_WATCHDOG_NOWAYOUT + * + * Version 0.6 (2002/04/12): Rob Radez + * - make mixcomwd_opened unsigned, + * removed lock_kernel/unlock_kernel from mixcomwd_release, + * modified ioctl a bit to conform to API + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#define VERSION "0.6" +#define WATCHDOG_NAME "mixcomwd" + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * We have two types of cards that can be probed: + * 1) The Mixcom cards: these cards can be found at addresses + * 0x180, 0x280, 0x380 with an additional offset of 0xc10. + * (Or 0xd90, 0xe90, 0xf90). + * 2) The FlashCOM cards: these cards can be set up at + * 0x300 -> 0x378, in 0x8 jumps with an offset of 0x04. + * (Or 0x304 -> 0x37c in 0x8 jumps). + * Each card has it's own ID. + */ +#define MIXCOM_ID 0x11 +#define FLASHCOM_ID 0x18 +static struct { + int ioport; + int id; +} mixcomwd_io_info[] = { + /* The Mixcom cards */ + {0x0d90, MIXCOM_ID}, + {0x0e90, MIXCOM_ID}, + {0x0f90, MIXCOM_ID}, + /* The FlashCOM cards */ + {0x0304, FLASHCOM_ID}, + {0x030c, FLASHCOM_ID}, + {0x0314, FLASHCOM_ID}, + {0x031c, FLASHCOM_ID}, + {0x0324, FLASHCOM_ID}, + {0x032c, FLASHCOM_ID}, + {0x0334, FLASHCOM_ID}, + {0x033c, FLASHCOM_ID}, + {0x0344, FLASHCOM_ID}, + {0x034c, FLASHCOM_ID}, + {0x0354, FLASHCOM_ID}, + {0x035c, FLASHCOM_ID}, + {0x0364, FLASHCOM_ID}, + {0x036c, FLASHCOM_ID}, + {0x0374, FLASHCOM_ID}, + {0x037c, FLASHCOM_ID}, + /* The end of the list */ + {0x0000, 0}, +}; + +static void mixcomwd_timerfun(unsigned long d); + +static unsigned long mixcomwd_opened; /* long req'd for setbit --RR */ + +static int watchdog_port; +static int mixcomwd_timer_alive; +static DEFINE_TIMER(mixcomwd_timer, mixcomwd_timerfun, 0, 0); +static char expect_close; + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, + "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +static void mixcomwd_ping(void) +{ + outb_p(55, watchdog_port); + return; +} + +static void mixcomwd_timerfun(unsigned long d) +{ + mixcomwd_ping(); + mod_timer(&mixcomwd_timer, jiffies + 5 * HZ); +} + +/* + * Allow only one person to hold it open + */ + +static int mixcomwd_open(struct inode *inode, struct file *file) +{ + if (test_and_set_bit(0, &mixcomwd_opened)) + return -EBUSY; + + mixcomwd_ping(); + + if (nowayout) + /* + * fops_get() code via open() has already done + * a try_module_get() so it is safe to do the + * __module_get(). + */ + __module_get(THIS_MODULE); + else { + if (mixcomwd_timer_alive) { + del_timer(&mixcomwd_timer); + mixcomwd_timer_alive = 0; + } + } + return nonseekable_open(inode, file); +} + +static int mixcomwd_release(struct inode *inode, struct file *file) +{ + if (expect_close == 42) { + if (mixcomwd_timer_alive) { + pr_err("release called while internal timer alive\n"); + return -EBUSY; + } + mixcomwd_timer_alive = 1; + mod_timer(&mixcomwd_timer, jiffies + 5 * HZ); + } else + pr_crit("WDT device closed unexpectedly. WDT will not stop!\n"); + + clear_bit(0, &mixcomwd_opened); + expect_close = 0; + return 0; +} + + +static ssize_t mixcomwd_write(struct file *file, const char __user *data, + size_t len, loff_t *ppos) +{ + if (len) { + if (!nowayout) { + size_t i; + + /* In case it was set long ago */ + expect_close = 0; + + for (i = 0; i != len; i++) { + char c; + if (get_user(c, data + i)) + return -EFAULT; + if (c == 'V') + expect_close = 42; + } + } + mixcomwd_ping(); + } + return len; +} + +static long mixcomwd_ioctl(struct file *file, + unsigned int cmd, unsigned long arg) +{ + void __user *argp = (void __user *)arg; + int __user *p = argp; + int status; + static const struct watchdog_info ident = { + .options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, + .firmware_version = 1, + .identity = "MixCOM watchdog", + }; + + switch (cmd) { + case WDIOC_GETSUPPORT: + if (copy_to_user(argp, &ident, sizeof(ident))) + return -EFAULT; + break; + case WDIOC_GETSTATUS: + status = mixcomwd_opened; + if (!nowayout) + status |= mixcomwd_timer_alive; + return put_user(status, p); + case WDIOC_GETBOOTSTATUS: + return put_user(0, p); + case WDIOC_KEEPALIVE: + mixcomwd_ping(); + break; + default: + return -ENOTTY; + } + return 0; +} + +static const struct file_operations mixcomwd_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = mixcomwd_write, + .unlocked_ioctl = mixcomwd_ioctl, + .open = mixcomwd_open, + .release = mixcomwd_release, +}; + +static struct miscdevice mixcomwd_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &mixcomwd_fops, +}; + +static int __init checkcard(int port, int card_id) +{ + int id; + + if (!request_region(port, 1, "MixCOM watchdog")) + return 0; + + id = inb_p(port); + if (card_id == MIXCOM_ID) + id &= 0x3f; + + if (id != card_id) { + release_region(port, 1); + return 0; + } + return 1; +} + +static int __init mixcomwd_init(void) +{ + int i, ret, found = 0; + + for (i = 0; !found && mixcomwd_io_info[i].ioport != 0; i++) { + if (checkcard(mixcomwd_io_info[i].ioport, + mixcomwd_io_info[i].id)) { + found = 1; + watchdog_port = mixcomwd_io_info[i].ioport; + } + } + + if (!found) { + pr_err("No card detected, or port not available\n"); + return -ENODEV; + } + + ret = misc_register(&mixcomwd_miscdev); + if (ret) { + pr_err("cannot register miscdev on minor=%d (err=%d)\n", + WATCHDOG_MINOR, ret); + goto error_misc_register_watchdog; + } + + pr_info("MixCOM watchdog driver v%s, watchdog port at 0x%3x\n", + VERSION, watchdog_port); + + return 0; + +error_misc_register_watchdog: + release_region(watchdog_port, 1); + watchdog_port = 0x0000; + return ret; +} + +static void __exit mixcomwd_exit(void) +{ + if (!nowayout) { + if (mixcomwd_timer_alive) { + pr_warn("I quit now, hardware will probably reboot!\n"); + del_timer_sync(&mixcomwd_timer); + mixcomwd_timer_alive = 0; + } + } + misc_deregister(&mixcomwd_miscdev); + release_region(watchdog_port, 1); +} + +module_init(mixcomwd_init); +module_exit(mixcomwd_exit); + +MODULE_AUTHOR("Gergely Madarasz "); +MODULE_DESCRIPTION("MixCom Watchdog driver"); +MODULE_VERSION(VERSION); +MODULE_LICENSE("GPL"); -- cgit v1.2.3-54-g00ecf