Commit 3a6a399c authored by Jean Delvare's avatar Jean Delvare Committed by Wim Van Sebroeck
Browse files

watchdog: Delete the cpu5wdt driver 



This driver has a number of issues (accesses arbitrary I/O ports
without identifying the hardware, doesn't document what hardware it
supports, suspiciously inconsistent locking model, doesn't implement
WDIOC_SETTIMEOUT, potential integer overflow...)

The driver was added in 2003 and there's no evidence that it has any
recent user, all changes seem to be tree-wide, subsystem-wide, or the
result of static code analysis. So I believe we should simply drop
this legacy piece of code.

Signed-off-by: default avatarJean Delvare <jdelvare@suse.de>
Message-ID: <20241011170710.484a257a@endymion.delvare>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20241022114731.31f69c94@endymion.delvare


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarWim Van Sebroeck <wim@linux-watchdog.org>
parent 3cf67f37

Documentation/watchdog/watchdog-parameters.rst

+0 −10
Original line number Diff line number Diff line
@@ -120,16 +120,6 @@ coh901327_wdt: 


-------------------------------------------------



cpu5wdt:

    port:

	base address of watchdog card, default is 0x91

    verbose:

	be verbose, default is 0 (no)

    ticks:

	count down ticks, default is 10000



-------------------------------------------------



cpwd:

    wd0_timeout:

	Default watchdog0 timeout in 1/10secs

drivers/watchdog/Kconfig

+0 −8
Original line number Diff line number Diff line
@@ -1541,14 +1541,6 @@ config SBC7240_WDT 
	  To compile this driver as a module, choose M here: the

	  module will be called sbc7240_wdt.



config CPU5_WDT

	tristate "SMA CPU5 Watchdog"

	depends on (X86 || COMPILE_TEST) && HAS_IOPORT

	help

	  TBD.

	  To compile this driver as a module, choose M here: the

	  module will be called cpu5wdt.



config SMSC_SCH311X_WDT

	tristate "SMSC SCH311X Watchdog Timer"

	depends on (X86 || COMPILE_TEST) && HAS_IOPORT

drivers/watchdog/Makefile

+0 −1
Original line number Diff line number Diff line
@@ -138,7 +138,6 @@ obj-$(CONFIG_RDC321X_WDT) += rdc321x_wdt.o 
obj-$(CONFIG_60XX_WDT) += sbc60xxwdt.o

obj-$(CONFIG_SBC8360_WDT) += sbc8360.o

obj-$(CONFIG_SBC7240_WDT) += sbc7240_wdt.o

obj-$(CONFIG_CPU5_WDT) += cpu5wdt.o

obj-$(CONFIG_SMSC_SCH311X_WDT) += sch311x_wdt.o

obj-$(CONFIG_SMSC37B787_WDT) += smsc37b787_wdt.o

obj-$(CONFIG_TQMX86_WDT) += tqmx86_wdt.o

drivers/watchdog/cpu5wdt.c

deleted100644 → 0
+0 −284
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * sma cpu5 watchdog driver

 *

 * Copyright (C) 2003 Heiko Ronsdorf <hero@ihg.uni-duisburg.de>

 */



#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt



#include <linux/module.h>

#include <linux/moduleparam.h>

#include <linux/types.h>

#include <linux/errno.h>

#include <linux/miscdevice.h>

#include <linux/fs.h>

#include <linux/ioport.h>

#include <linux/timer.h>

#include <linux/completion.h>

#include <linux/jiffies.h>

#include <linux/io.h>

#include <linux/uaccess.h>

#include <linux/watchdog.h>



/* adjustable parameters */



static int verbose;

static int port = 0x91;

static int ticks = 10000;

static DEFINE_SPINLOCK(cpu5wdt_lock);



#define PFX			"cpu5wdt: "



#define CPU5WDT_EXTENT          0x0A



#define CPU5WDT_STATUS_REG      0x00

#define CPU5WDT_TIME_A_REG      0x02

#define CPU5WDT_TIME_B_REG      0x03

#define CPU5WDT_MODE_REG        0x04

#define CPU5WDT_TRIGGER_REG     0x07

#define CPU5WDT_ENABLE_REG      0x08

#define CPU5WDT_RESET_REG       0x09



#define CPU5WDT_INTERVAL	(HZ/10+1)



/* some device data */



static struct {

	struct completion stop;

	int running;

	struct timer_list timer;

	int queue;

	int default_ticks;

	unsigned long inuse;

} cpu5wdt_device;



/* generic helper functions */



static void cpu5wdt_trigger(struct timer_list *unused)

{

	if (verbose > 2)

		pr_debug("trigger at %i ticks\n", ticks);



	if (cpu5wdt_device.running)

		ticks--;



	spin_lock(&cpu5wdt_lock);

	/* keep watchdog alive */

	outb(1, port + CPU5WDT_TRIGGER_REG);



	/* requeue?? */

	if (cpu5wdt_device.queue && ticks)

		mod_timer(&cpu5wdt_device.timer, jiffies + CPU5WDT_INTERVAL);

	else {

		/* ticks doesn't matter anyway */

		complete(&cpu5wdt_device.stop);

	}

	spin_unlock(&cpu5wdt_lock);



}



static void cpu5wdt_reset(void)

{

	ticks = cpu5wdt_device.default_ticks;



	if (verbose)

		pr_debug("reset (%i ticks)\n", (int) ticks);



}



static void cpu5wdt_start(void)

{

	unsigned long flags;



	spin_lock_irqsave(&cpu5wdt_lock, flags);

	if (!cpu5wdt_device.queue) {

		cpu5wdt_device.queue = 1;

		outb(0, port + CPU5WDT_TIME_A_REG);

		outb(0, port + CPU5WDT_TIME_B_REG);

		outb(1, port + CPU5WDT_MODE_REG);

		outb(0, port + CPU5WDT_RESET_REG);

		outb(0, port + CPU5WDT_ENABLE_REG);

		mod_timer(&cpu5wdt_device.timer, jiffies + CPU5WDT_INTERVAL);

	}

	/* if process dies, counter is not decremented */

	cpu5wdt_device.running++;

	spin_unlock_irqrestore(&cpu5wdt_lock, flags);

}



static int cpu5wdt_stop(void)

{

	unsigned long flags;



	spin_lock_irqsave(&cpu5wdt_lock, flags);

	if (cpu5wdt_device.running)

		cpu5wdt_device.running = 0;

	ticks = cpu5wdt_device.default_ticks;

	spin_unlock_irqrestore(&cpu5wdt_lock, flags);

	if (verbose)

		pr_crit("stop not possible\n");

	return -EIO;

}



/* filesystem operations */



static int cpu5wdt_open(struct inode *inode, struct file *file)

{

	if (test_and_set_bit(0, &cpu5wdt_device.inuse))

		return -EBUSY;

	return stream_open(inode, file);

}



static int cpu5wdt_release(struct inode *inode, struct file *file)

{

	clear_bit(0, &cpu5wdt_device.inuse);

	return 0;

}



static long cpu5wdt_ioctl(struct file *file, unsigned int cmd,

						unsigned long arg)

{

	void __user *argp = (void __user *)arg;

	int __user *p = argp;

	unsigned int value;

	static const struct watchdog_info ident = {

		.options = WDIOF_CARDRESET,

		.identity = "CPU5 WDT",

	};



	switch (cmd) {

	case WDIOC_GETSUPPORT:

		if (copy_to_user(argp, &ident, sizeof(ident)))

			return -EFAULT;

		break;

	case WDIOC_GETSTATUS:

		value = inb(port + CPU5WDT_STATUS_REG);

		value = (value >> 2) & 1;

		return put_user(value, p);

	case WDIOC_GETBOOTSTATUS:

		return put_user(0, p);

	case WDIOC_SETOPTIONS:

		if (get_user(value, p))

			return -EFAULT;

		if (value & WDIOS_ENABLECARD)

			cpu5wdt_start();

		if (value & WDIOS_DISABLECARD)

			cpu5wdt_stop();

		break;

	case WDIOC_KEEPALIVE:

		cpu5wdt_reset();

		break;

	default:

		return -ENOTTY;

	}

	return 0;

}



static ssize_t cpu5wdt_write(struct file *file, const char __user *buf,

						size_t count, loff_t *ppos)

{

	if (!count)

		return -EIO;

	cpu5wdt_reset();

	return count;

}



static const struct file_operations cpu5wdt_fops = {

	.owner		= THIS_MODULE,

	.unlocked_ioctl	= cpu5wdt_ioctl,

	.compat_ioctl	= compat_ptr_ioctl,

	.open		= cpu5wdt_open,

	.write		= cpu5wdt_write,

	.release	= cpu5wdt_release,

};



static struct miscdevice cpu5wdt_misc = {

	.minor	= WATCHDOG_MINOR,

	.name	= "watchdog",

	.fops	= &cpu5wdt_fops,

};



/* init/exit function */



static int cpu5wdt_init(void)

{

	unsigned int val;

	int err;



	if (verbose)

		pr_debug("port=0x%x, verbose=%i\n", port, verbose);



	init_completion(&cpu5wdt_device.stop);

	cpu5wdt_device.queue = 0;

	timer_setup(&cpu5wdt_device.timer, cpu5wdt_trigger, 0);

	cpu5wdt_device.default_ticks = ticks;



	if (!request_region(port, CPU5WDT_EXTENT, PFX)) {

		pr_err("request_region failed\n");

		err = -EBUSY;

		goto no_port;

	}



	/* watchdog reboot? */

	val = inb(port + CPU5WDT_STATUS_REG);

	val = (val >> 2) & 1;

	if (!val)

		pr_info("sorry, was my fault\n");



	err = misc_register(&cpu5wdt_misc);

	if (err < 0) {

		pr_err("misc_register failed\n");

		goto no_misc;

	}





	pr_info("init success\n");

	return 0;



no_misc:

	release_region(port, CPU5WDT_EXTENT);

no_port:

	return err;

}



static int cpu5wdt_init_module(void)

{

	return cpu5wdt_init();

}



static void cpu5wdt_exit(void)

{

	if (cpu5wdt_device.queue) {

		cpu5wdt_device.queue = 0;

		wait_for_completion(&cpu5wdt_device.stop);

		timer_shutdown_sync(&cpu5wdt_device.timer);

	}



	misc_deregister(&cpu5wdt_misc);



	release_region(port, CPU5WDT_EXTENT);



}



static void cpu5wdt_exit_module(void)

{

	cpu5wdt_exit();

}



/* module entry points */



module_init(cpu5wdt_init_module);

module_exit(cpu5wdt_exit_module);



MODULE_AUTHOR("Heiko Ronsdorf <hero@ihg.uni-duisburg.de>");

MODULE_DESCRIPTION("sma cpu5 watchdog driver");

MODULE_LICENSE("GPL");



module_param_hw(port, int, ioport, 0);

MODULE_PARM_DESC(port, "base address of watchdog card, default is 0x91");



module_param(verbose, int, 0);

MODULE_PARM_DESC(verbose, "be verbose, default is 0 (no)");



module_param(ticks, int, 0);

MODULE_PARM_DESC(ticks, "count down ticks, default is 10000");