1 // SPDX-License-Identifier: GPL-2.0-or-later
9  *	any of this software. This material is provided "AS-IS" in
12  *	(C) Copyright 2003-2006  Sven Anders <anders@anduras.de>
15  *	2003 - Created version 1.0 for Linux 2.4.x.
16  *	2006 - Ported to Linux 2.6, added nowayout and MAGICCLOSE
33  *	reset the system (causing a reboot) after the timeout occurs.
38  * For an example userspace keep-alive daemon, see:
60 /* enable support for minutes as units? */
77 static int timeout = 60;	/* timeout value: default is 60 "units" */  variable
86 /* -- Low level function ----------------------------------------*/
124 /* -- Medium level functions ------------------------------------*/
128 	/* -- General Purpose I/O Bit 1.2 --  in gpio_bit12()
131 	 * Bit 2,   Group Enable Intr.: 0 = Disable, 1 = Enable  in gpio_bit12()
142 	/* -- General Purpose I/O Bit 1.3 --  in gpio_bit13()
145 	 * Bit 2,  Group Enable Intr.: 0 = Disable, 1 = Enable  in gpio_bit13()
147 	 * Bit 4-6 (Reserved)  in gpio_bit13()
155 	/* -- Watchdog timer units --  in wdt_timer_units()
156 	 * Bit 0-6 (Reserved)  in wdt_timer_units()
157 	 * Bit 7,  WDT Time-out Value Units Select  in wdt_timer_units()
165 	/* -- Watchdog Timer Time-out Value --  in wdt_timeout_value()
166 	 * Bit 0-7 Binary coded units (0=Disabled, 1..255)  in wdt_timeout_value()
173 	/* -- Watchdog timer configuration --  in wdt_timer_conf()
174 	 * Bit 0   Joystick enable: 0* = No Reset, 1 = Reset WDT upon  in wdt_timer_conf()
176 	 * Bit 1   Keyboard enable: 0* = No Reset, 1 = Reset WDT upon KBD Intr.  in wdt_timer_conf()
177 	 * Bit 2   Mouse enable: 0* = No Reset, 1 = Reset WDT upon Mouse Intr  in wdt_timer_conf()
181 	 * Bit 4-7 WDT Interrupt Mapping: (0000* = Disabled,  in wdt_timer_conf()
189 	/* -- Watchdog timer control --  in wdt_timer_ctrl()
190 	 * Bit 0   Status Bit: 0 = Timer counting, 1 = Timeout occurred  in wdt_timer_ctrl()
192 	 * Bit 2   Force Timeout: 1 = Forces WD timeout event (self-cleaning)  in wdt_timer_ctrl()
193 	 * Bit 3   P20 Force Timeout enabled:  in wdt_timer_ctrl()
194 	 *          0 = P20 activity does not generate the WD timeout event  in wdt_timer_ctrl()
196 	 *              controller, to force the WD timeout event.  in wdt_timer_ctrl()
198 	 * -- Soft power management --  in wdt_timer_ctrl()
200 	 *            set via register 0xB8, (self-cleaning)  in wdt_timer_ctrl()
203 	 *            set via register 0xB8, (self-cleaning)  in wdt_timer_ctrl()
204 	 * Bit 7   SPOFF: 1 = Force software power down (self-cleaning)  in wdt_timer_ctrl()
209 /* -- Higher level functions ------------------------------------*/
221 	/* enable the watchdog */  in wb_smsc_wdt_initialize()
225 	/* disable the timeout */  in wb_smsc_wdt_initialize()
264 	/* disable timeout */  in wb_smsc_wdt_shutdown()
271 /* set timeout => enable watchdog */
279 	/* set Power LED to blink, if we enable the timeout */  in wb_smsc_wdt_set_timeout()
282 	/* set timeout value */  in wb_smsc_wdt_set_timeout()
289 /* get timeout */
309 	/* set the timeout to 0 to disable the watchdog */  in wb_smsc_wdt_disable()
313 /* enable watchdog by setting the current timeout */
317 	/* set the current timeout... */  in wb_smsc_wdt_enable()
318 	wb_smsc_wdt_set_timeout(timeout);  in wb_smsc_wdt_enable()
330 	wdt_timeout_value(timeout);  in wb_smsc_wdt_reset_timer()
337 /* return, if the watchdog is enabled (timeout is set...) */
345 /* -- File operations -------------------------------------------*/
347 /* open => enable watchdog and set initial timeout */
354 		return -EBUSY;  in wb_smsc_wdt_open()
362 	pr_info("Watchdog enabled. Timeout set to %d %s\n",  in wb_smsc_wdt_open()
363 		timeout, (unit == UNIT_SECOND) ? "second(s)" : "minute(s)");  in wb_smsc_wdt_open()
405 					return -EFAULT;  in wb_smsc_wdt_write()
442 								? -EFAULT : 0;  in wb_smsc_wdt_ioctl()
449 		int options, retval = -EINVAL;  in wb_smsc_wdt_ioctl()
452 			return -EFAULT;  in wb_smsc_wdt_ioctl()
469 			return -EFAULT;  in wb_smsc_wdt_ioctl()
474 			return -EINVAL;  in wb_smsc_wdt_ioctl()
475 		timeout = new_timeout;  in wb_smsc_wdt_ioctl()
476 		wb_smsc_wdt_set_timeout(timeout);  in wb_smsc_wdt_ioctl()
477 		fallthrough;	/* and return the new timeout */  in wb_smsc_wdt_ioctl()
479 		new_timeout = timeout;  in wb_smsc_wdt_ioctl()
484 		return -ENOTTY;  in wb_smsc_wdt_ioctl()
488 /* -- Notifier funtions -----------------------------------------*/
494 		/* set timeout to 0, to avoid possible race-condition */  in wb_smsc_wdt_notify_sys()
495 		timeout = 0;  in wb_smsc_wdt_notify_sys()
501 /* -- Module's structures ---------------------------------------*/
522 /* -- Module init functions -------------------------------------*/
535 		ret = -EBUSY;  in wb_smsc_wdt_init()
540 	if (timeout > MAX_TIMEOUT)  in wb_smsc_wdt_init()
541 		timeout = MAX_TIMEOUT;  in wb_smsc_wdt_init()
560 	pr_info("Timeout set to %d %s\n",  in wb_smsc_wdt_init()
561 		timeout, (unit == UNIT_SECOND) ? "second(s)" : "minute(s)");  in wb_smsc_wdt_init()
608 module_param(timeout, int, 0);
609 MODULE_PARM_DESC(timeout, "range is 1-255 units, default is 60");