cregit-Linux how code gets into the kernel

Release 4.10 drivers/watchdog/sc1200wdt.c

Directory: drivers/watchdog
/*
 *      National Semiconductor PC87307/PC97307 (ala SC1200) WDT driver
 *      (c) Copyright 2002 Zwane Mwaikambo <zwane@commfireservices.com>,
 *                      All Rights Reserved.
 *      Based on wdt.c and wdt977.c by Alan Cox and Woody Suwalski respectively.
 *
 *      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.
 *
 *      The author(s) of this software shall not be held liable for damages
 *      of any nature resulting due to the use of this software. This
 *      software is provided AS-IS with no warranties.
 *
 *      Changelog:
 *      20020220 Zwane Mwaikambo        Code based on datasheet, no hardware.
 *      20020221 Zwane Mwaikambo        Cleanups as suggested by Jeff Garzik
 *                                      and Alan Cox.
 *      20020222 Zwane Mwaikambo        Added probing.
 *      20020225 Zwane Mwaikambo        Added ISAPNP support.
 *      20020412 Rob Radez              Broke out start/stop functions
 *               <rob@osinvestor.com>   Return proper status instead of
 *                                      temperature warning
 *                                      Add WDIOC_GETBOOTSTATUS and
 *                                      WDIOC_SETOPTIONS ioctls
 *                                      Fix CONFIG_WATCHDOG_NOWAYOUT
 *      20020530 Joel Becker            Add Matt Domsch's nowayout module
 *                                      option
 *      20030116 Adam Belay             Updated to the latest pnp code
 *
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/ioport.h>
#include <linux/spinlock.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/pnp.h>
#include <linux/fs.h>
#include <linux/semaphore.h>
#include <linux/io.h>
#include <linux/uaccess.h>


#define SC1200_MODULE_VER	"build 20020303"

#define SC1200_MODULE_NAME	"sc1200wdt"


#define	MAX_TIMEOUT	255	
/* 255 minutes */

#define PMIR		(io)	
/* Power Management Index Register */

#define PMDR		(io+1)	
/* Power Management Data Register */

/* Data Register indexes */

#define FER1		0x00	
/* Function enable register 1 */

#define FER2		0x01	
/* Function enable register 2 */

#define PMC1		0x02	
/* Power Management Ctrl 1 */

#define PMC2		0x03	
/* Power Management Ctrl 2 */

#define PMC3		0x04	
/* Power Management Ctrl 3 */

#define WDTO		0x05	
/* Watchdog timeout register */

#define	WDCF		0x06	
/* Watchdog config register */

#define WDST		0x07	
/* Watchdog status register */

/* WDCF bitfields - which devices assert WDO */

#define KBC_IRQ		0x01	
/* Keyboard Controller */

#define MSE_IRQ		0x02	
/* Mouse */

#define UART1_IRQ	0x03	
/* Serial0 */

#define UART2_IRQ	0x04	
/* Serial1 */
/* 5 -7 are reserved */


static int timeout = 1;

static int io = -1;

static int io_len = 2;		
/* for non plug and play */

static unsigned long open_flag;

static char expect_close;
static DEFINE_SPINLOCK(sc1200wdt_lock);	/* io port access serialisation */

#if defined CONFIG_PNP

static int isapnp = 1;

static struct pnp_dev *wdt_dev;

module_param(isapnp, int, 0);
MODULE_PARM_DESC(isapnp,
	"When set to 0 driver ISA PnP support will be disabled");
#endif

module_param(io, int, 0);
MODULE_PARM_DESC(io, "io port");
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout, "range is 0-255 minutes, default is 1");


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) ")");



/* Read from Data Register */

static inline void __sc1200wdt_read_data(unsigned char index, unsigned char *data) { outb_p(index, PMIR); *data = inb(PMDR); }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones2993.55%150.00%
alan coxalan cox26.45%150.00%
Total31100.00%2100.00%


static void sc1200wdt_read_data(unsigned char index, unsigned char *data) { spin_lock(&sc1200wdt_lock); __sc1200wdt_read_data(index, data); spin_unlock(&sc1200wdt_lock); }

Contributors

PersonTokensPropCommitsCommitProp
alan coxalan cox2779.41%150.00%
dave jonesdave jones720.59%150.00%
Total34100.00%2100.00%

/* Write to Data Register */
static inline void __sc1200wdt_write_data(unsigned char index, unsigned char data) { outb_p(index, PMIR); outb(data, PMDR); }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones2793.10%150.00%
alan coxalan cox26.90%150.00%
Total29100.00%2100.00%


static inline void sc1200wdt_write_data(unsigned char index, unsigned char data) { spin_lock(&sc1200wdt_lock); __sc1200wdt_write_data(index, data); spin_unlock(&sc1200wdt_lock); }

Contributors

PersonTokensPropCommitsCommitProp
alan coxalan cox2779.41%150.00%
dave jonesdave jones720.59%150.00%
Total34100.00%2100.00%


static void sc1200wdt_start(void) { unsigned char reg; spin_lock(&sc1200wdt_lock); __sc1200wdt_read_data(WDCF, &reg); /* assert WDO when any of the following interrupts are triggered too */ reg |= (KBC_IRQ | MSE_IRQ | UART1_IRQ | UART2_IRQ); __sc1200wdt_write_data(WDCF, reg); /* set the timeout and get the ball rolling */ __sc1200wdt_write_data(WDTO, timeout); spin_unlock(&sc1200wdt_lock); }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones4575.00%150.00%
alan coxalan cox1525.00%150.00%
Total60100.00%2100.00%


static void sc1200wdt_stop(void) { sc1200wdt_write_data(WDTO, 0); }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones15100.00%1100.00%
Total15100.00%1100.00%

/* This returns the status of the WDO signal, inactive high. */
static inline int sc1200wdt_status(void) { unsigned char ret; sc1200wdt_read_data(WDST, &ret); /* If the bit is inactive, the watchdog is enabled, so return * KEEPALIVEPING which is a bit of a kludge because there's nothing * else for enabled/disabled status */ return (ret & 0x01) ? 0 : WDIOF_KEEPALIVEPING; }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones33100.00%1100.00%
Total33100.00%1100.00%


static int sc1200wdt_open(struct inode *inode, struct file *file) { /* allow one at a time */ if (test_and_set_bit(0, &open_flag)) return -EBUSY; if (timeout > MAX_TIMEOUT) timeout = MAX_TIMEOUT; sc1200wdt_start(); pr_info("Watchdog enabled, timeout = %d min(s)", timeout); return nonseekable_open(inode, file); }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones4677.97%125.00%
wim van sebroeckwim van sebroeck610.17%125.00%
alan coxalan cox46.78%125.00%
joe perchesjoe perches35.08%125.00%
Total59100.00%4100.00%


static long sc1200wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { int new_timeout; void __user *argp = (void __user *)arg; int __user *p = argp; static const struct watchdog_info ident = { .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, .firmware_version = 0, .identity = "PC87307/PC97307", }; switch (cmd) { case WDIOC_GETSUPPORT: if (copy_to_user(argp, &ident, sizeof(ident))) return -EFAULT; return 0; case WDIOC_GETSTATUS: return put_user(sc1200wdt_status(), p); case WDIOC_GETBOOTSTATUS: return put_user(0, p); case WDIOC_SETOPTIONS: { int options, retval = -EINVAL; if (get_user(options, p)) return -EFAULT; if (options & WDIOS_DISABLECARD) { sc1200wdt_stop(); retval = 0; } if (options & WDIOS_ENABLECARD) { sc1200wdt_start(); retval = 0; } return retval; } case WDIOC_KEEPALIVE: sc1200wdt_write_data(WDTO, timeout); return 0; case WDIOC_SETTIMEOUT: if (get_user(new_timeout, p)) return -EFAULT; /* the API states this is given in secs */ new_timeout /= 60; if (new_timeout < 0 || new_timeout > MAX_TIMEOUT) return -EINVAL; timeout = new_timeout; sc1200wdt_write_data(WDTO, timeout); /* fall through and return the new timeout */ case WDIOC_GETTIMEOUT: return put_user(timeout * 60, p); default: return -ENOTTY; } }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones16664.09%228.57%
wim van sebroeckwim van sebroeck6223.94%342.86%
al viroal viro249.27%114.29%
alan coxalan cox72.70%114.29%
Total259100.00%7100.00%


static int sc1200wdt_release(struct inode *inode, struct file *file) { if (expect_close == 42) { sc1200wdt_stop(); pr_info("Watchdog disabled\n"); } else { sc1200wdt_write_data(WDTO, timeout); pr_crit("Unexpected close!, timeout = %d min(s)\n", timeout); } clear_bit(0, &open_flag); expect_close = 0; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones5585.94%133.33%
joe perchesjoe perches57.81%133.33%
alan coxalan cox46.25%133.33%
Total64100.00%3100.00%


static ssize_t sc1200wdt_write(struct file *file, const char __user *data, size_t len, loff_t *ppos) { if (len) { if (!nowayout) { size_t i; 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; } } sc1200wdt_write_data(WDTO, timeout); return len; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones9999.00%266.67%
al viroal viro11.00%133.33%
Total100100.00%3100.00%


static int sc1200wdt_notify_sys(struct notifier_block *this, unsigned long code, void *unused) { if (code == SYS_DOWN || code == SYS_HALT) sc1200wdt_stop(); return NOTIFY_DONE; }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones35100.00%1100.00%
Total35100.00%1100.00%

static struct notifier_block sc1200wdt_notifier = { .notifier_call = sc1200wdt_notify_sys, }; static const struct file_operations sc1200wdt_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .write = sc1200wdt_write, .unlocked_ioctl = sc1200wdt_ioctl, .open = sc1200wdt_open, .release = sc1200wdt_release, }; static struct miscdevice sc1200wdt_miscdev = { .minor = WATCHDOG_MINOR, .name = "watchdog", .fops = &sc1200wdt_fops, };
static int __init sc1200wdt_probe(void) { /* The probe works by reading the PMC3 register's default value of 0x0e * there is one caveat, if the device disables the parallel port or any * of the UARTs we won't be able to detect it. * NB. This could be done with accuracy by reading the SID registers, * but we don't have access to those io regions. */ unsigned char reg; sc1200wdt_read_data(PMC3, &reg); reg &= 0x0f; /* we don't want the UART busy bits */ return (reg == 0x0e) ? 0 : -ENODEV; }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones3897.44%150.00%
alan coxalan cox12.56%150.00%
Total39100.00%2100.00%

#if defined CONFIG_PNP static struct pnp_device_id scl200wdt_pnp_devices[] = { /* National Semiconductor PC87307/PC97307 watchdog component */ {.id = "NSC0800", .driver_data = 0}, {.id = ""}, };
static int scl200wdt_pnp_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id) { /* this driver only supports one card at a time */ if (wdt_dev || !isapnp) return -EBUSY; wdt_dev = dev; io = pnp_port_start(wdt_dev, 0); io_len = pnp_port_len(wdt_dev, 0); if (!request_region(io, io_len, SC1200_MODULE_NAME)) { pr_err("Unable to register IO port %#x\n", io); return -EBUSY; } pr_info("PnP device found at io port %#x/%d\n", io, io_len); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones8394.32%266.67%
joe perchesjoe perches55.68%133.33%
Total88100.00%3100.00%


static void scl200wdt_pnp_remove(struct pnp_dev *dev) { if (wdt_dev) { release_region(io, io_len); wdt_dev = NULL; } }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones28100.00%2100.00%
Total28100.00%2100.00%

static struct pnp_driver scl200wdt_pnp_driver = { .name = "scl200wdt", .id_table = scl200wdt_pnp_devices, .probe = scl200wdt_pnp_probe, .remove = scl200wdt_pnp_remove, }; #endif /* CONFIG_PNP */
static int __init sc1200wdt_init(void) { int ret; pr_info("%s\n", SC1200_MODULE_VER); #if defined CONFIG_PNP if (isapnp) { ret = pnp_register_driver(&scl200wdt_pnp_driver); if (ret) goto out_clean; } #endif if (io == -1) { pr_err("io parameter must be specified\n"); ret = -EINVAL; goto out_pnp; } #if defined CONFIG_PNP /* now that the user has specified an IO port and we haven't detected * any devices, disable pnp support */ if (isapnp) pnp_unregister_driver(&scl200wdt_pnp_driver); isapnp = 0; #endif if (!request_region(io, io_len, SC1200_MODULE_NAME)) { pr_err("Unable to register IO port %#x\n", io); ret = -EBUSY; goto out_pnp; } ret = sc1200wdt_probe(); if (ret) goto out_io; ret = register_reboot_notifier(&sc1200wdt_notifier); if (ret) { pr_err("Unable to register reboot notifier err = %d\n", ret); goto out_io; } ret = misc_register(&sc1200wdt_miscdev); if (ret) { pr_err("Unable to register miscdev on minor %d\n", WATCHDOG_MINOR); goto out_rbt; } /* ret = 0 */ out_clean: return ret; out_rbt: unregister_reboot_notifier(&sc1200wdt_notifier); out_io: release_region(io, io_len); out_pnp: #if defined CONFIG_PNP if (isapnp) pnp_unregister_driver(&scl200wdt_pnp_driver); #endif goto out_clean; }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones18281.98%457.14%
akinobu mitaakinobu mita209.01%114.29%
joe perchesjoe perches135.86%114.29%
alan one thousand gnomesalan one thousand gnomes73.15%114.29%
Total222100.00%7100.00%


static void __exit sc1200wdt_exit(void) { misc_deregister(&sc1200wdt_miscdev); unregister_reboot_notifier(&sc1200wdt_notifier); #if defined CONFIG_PNP if (isapnp) pnp_unregister_driver(&scl200wdt_pnp_driver); else #endif release_region(io, io_len); }

Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones45100.00%2100.00%
Total45100.00%2100.00%

module_init(sc1200wdt_init); module_exit(sc1200wdt_exit); MODULE_AUTHOR("Zwane Mwaikambo <zwane@commfireservices.com>"); MODULE_DESCRIPTION( "Driver for National Semiconductor PC87307/PC97307 watchdog component"); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
dave jonesdave jones130581.41%726.92%
alan coxalan cox965.99%13.85%
wim van sebroeckwim van sebroeck895.55%830.77%
joe perchesjoe perches332.06%13.85%
al viroal viro251.56%13.85%
akinobu mitaakinobu mita201.25%13.85%
andrew mortonandrew morton181.12%13.85%
alan one thousand gnomesalan one thousand gnomes70.44%13.85%
alexey dobriyanalexey dobriyan40.25%13.85%
adrian bunkadrian bunk30.19%13.85%
matthew wilcoxmatthew wilcox10.06%13.85%
andrey paninandrey panin10.06%13.85%
arjan van de venarjan van de ven10.06%13.85%
Total1603100.00%26100.00%
Directory: drivers/watchdog
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.