2 * sch311x_wdt.c - Driver for the SCH311x Super-I/O chips
5 * (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
12 * Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
13 * provide warranty for any of this software. This material is
14 * provided "AS-IS" and at no charge.
18 * Includes, defines, variables, module parameters, ...
22 #include <linux/module.h> /* For module specific items */
23 #include <linux/moduleparam.h> /* For new moduleparam's */
24 #include <linux/types.h> /* For standard types (like size_t) */
25 #include <linux/errno.h> /* For the -ENODEV/... values */
26 #include <linux/kernel.h> /* For printk/... */
27 #include <linux/miscdevice.h> /* For MODULE_ALIAS_MISCDEV
29 #include <linux/watchdog.h> /* For the watchdog specific items */
30 #include <linux/init.h> /* For __init/__exit/... */
31 #include <linux/fs.h> /* For file operations */
32 #include <linux/platform_device.h> /* For platform_driver framework */
33 #include <linux/ioport.h> /* For io-port access */
34 #include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
35 #include <linux/uaccess.h> /* For copy_to_user/put_user/... */
36 #include <linux/io.h> /* For inb/outb/... */
38 /* Module and version information */
39 #define DRV_NAME "sch311x_wdt"
40 #define PFX DRV_NAME ": "
42 /* Runtime registers */
45 #define WDT_TIME_OUT 0x65
50 /* internal variables */
51 static unsigned long sch311x_wdt_is_open;
52 static char sch311x_wdt_expect_close;
53 static struct platform_device *sch311x_wdt_pdev;
55 static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e, 0x00 };
57 static struct { /* The devices private data */
58 /* the Runtime Register base address */
59 unsigned short runtime_reg;
60 /* The card's boot status */
62 /* the lock for io operations */
66 /* Module load parameters */
67 static unsigned short force_id;
68 module_param(force_id, ushort, 0);
69 MODULE_PARM_DESC(force_id, "Override the detected device ID");
71 static unsigned short therm_trip;
72 module_param(therm_trip, ushort, 0);
73 MODULE_PARM_DESC(therm_trip, "Should a ThermTrip trigger the reset generator");
75 #define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
76 static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
77 module_param(timeout, int, 0);
78 MODULE_PARM_DESC(timeout,
79 "Watchdog timeout in seconds. 1<= timeout <=15300, default="
80 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
82 static int nowayout = WATCHDOG_NOWAYOUT;
83 module_param(nowayout, int, 0);
84 MODULE_PARM_DESC(nowayout,
85 "Watchdog cannot be stopped once started (default="
86 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
92 static inline void sch311x_sio_enter(int sio_config_port)
94 outb(0x55, sio_config_port);
97 static inline void sch311x_sio_exit(int sio_config_port)
99 outb(0xaa, sio_config_port);
102 static inline int sch311x_sio_inb(int sio_config_port, int reg)
104 outb(reg, sio_config_port);
105 return inb(sio_config_port + 1);
108 static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
110 outb(reg, sio_config_port);
111 outb(val, sio_config_port + 1);
115 * Watchdog Operations
118 static void sch311x_wdt_set_timeout(int t)
120 unsigned char timeout_unit = 0x80;
122 /* When new timeout is bigger then 255 seconds, we will use minutes */
128 /* -- Watchdog Timeout --
130 * Bit 7 WDT Time-out Value Units Select
131 * (0 = Minutes, 1 = Seconds)
133 outb(timeout_unit, sch311x_wdt_data.runtime_reg + WDT_TIME_OUT);
135 /* -- Watchdog Timer Time-out Value --
136 * Bit 0-7 Binary coded units (0=Disabled, 1..255)
138 outb(t, sch311x_wdt_data.runtime_reg + WDT_VAL);
141 static void sch311x_wdt_start(void)
143 spin_lock(&sch311x_wdt_data.io_lock);
145 /* set watchdog's timeout */
146 sch311x_wdt_set_timeout(timeout);
147 /* enable the watchdog */
148 /* -- General Purpose I/O Bit 6.0 --
149 * Bit 0, In/Out: 0 = Output, 1 = Input
150 * Bit 1, Polarity: 0 = No Invert, 1 = Invert
151 * Bit 2-3, Function select: 00 = GPI/O, 01 = LED1, 11 = WDT,
152 * 10 = Either Edge Triggered Intr.4
154 * Bit 7, Output Type: 0 = Push Pull Bit, 1 = Open Drain
156 outb(0x0e, sch311x_wdt_data.runtime_reg + GP60);
158 spin_unlock(&sch311x_wdt_data.io_lock);
162 static void sch311x_wdt_stop(void)
164 spin_lock(&sch311x_wdt_data.io_lock);
166 /* stop the watchdog */
167 outb(0x01, sch311x_wdt_data.runtime_reg + GP60);
168 /* disable timeout by setting it to 0 */
169 sch311x_wdt_set_timeout(0);
171 spin_unlock(&sch311x_wdt_data.io_lock);
174 static void sch311x_wdt_keepalive(void)
176 spin_lock(&sch311x_wdt_data.io_lock);
177 sch311x_wdt_set_timeout(timeout);
178 spin_unlock(&sch311x_wdt_data.io_lock);
181 static int sch311x_wdt_set_heartbeat(int t)
183 if (t < 1 || t > (255*60))
186 /* When new timeout is bigger then 255 seconds,
187 * we will round up to minutes (with a max of 255) */
189 t = (((t - 1) / 60) + 1) * 60;
195 static void sch311x_wdt_get_status(int *status)
197 unsigned char new_status;
201 spin_lock(&sch311x_wdt_data.io_lock);
203 /* -- Watchdog timer control --
204 * Bit 0 Status Bit: 0 = Timer counting, 1 = Timeout occured
206 * Bit 2 Force Timeout: 1 = Forces WD timeout event (self-cleaning)
207 * Bit 3 P20 Force Timeout enabled:
208 * 0 = P20 activity does not generate the WD timeout event
209 * 1 = P20 Allows rising edge of P20, from the keyboard
210 * controller, to force the WD timeout event.
213 new_status = inb(sch311x_wdt_data.runtime_reg + WDT_CTRL);
214 if (new_status & 0x01)
215 *status |= WDIOF_CARDRESET;
217 spin_unlock(&sch311x_wdt_data.io_lock);
221 * /dev/watchdog handling
224 static ssize_t sch311x_wdt_write(struct file *file, const char __user *buf,
225 size_t count, loff_t *ppos)
231 sch311x_wdt_expect_close = 0;
233 for (i = 0; i != count; i++) {
235 if (get_user(c, buf + i))
238 sch311x_wdt_expect_close = 42;
241 sch311x_wdt_keepalive();
246 static long sch311x_wdt_ioctl(struct file *file, unsigned int cmd,
251 void __user *argp = (void __user *)arg;
252 int __user *p = argp;
253 static const struct watchdog_info ident = {
254 .options = WDIOF_KEEPALIVEPING |
257 .firmware_version = 1,
258 .identity = DRV_NAME,
262 case WDIOC_GETSUPPORT:
263 if (copy_to_user(argp, &ident, sizeof(ident)))
267 case WDIOC_GETSTATUS:
269 sch311x_wdt_get_status(&status);
270 return put_user(status, p);
272 case WDIOC_GETBOOTSTATUS:
273 return put_user(sch311x_wdt_data.boot_status, p);
275 case WDIOC_SETOPTIONS:
277 int options, retval = -EINVAL;
279 if (get_user(options, p))
281 if (options & WDIOS_DISABLECARD) {
285 if (options & WDIOS_ENABLECARD) {
291 case WDIOC_KEEPALIVE:
292 sch311x_wdt_keepalive();
295 case WDIOC_SETTIMEOUT:
296 if (get_user(new_timeout, p))
298 if (sch311x_wdt_set_heartbeat(new_timeout))
300 sch311x_wdt_keepalive();
302 case WDIOC_GETTIMEOUT:
303 return put_user(timeout, p);
310 static int sch311x_wdt_open(struct inode *inode, struct file *file)
312 if (test_and_set_bit(0, &sch311x_wdt_is_open))
318 return nonseekable_open(inode, file);
321 static int sch311x_wdt_close(struct inode *inode, struct file *file)
323 if (sch311x_wdt_expect_close == 42) {
327 "Unexpected close, not stopping watchdog!\n");
328 sch311x_wdt_keepalive();
330 clear_bit(0, &sch311x_wdt_is_open);
331 sch311x_wdt_expect_close = 0;
339 static const struct file_operations sch311x_wdt_fops = {
340 .owner = THIS_MODULE,
342 .write = sch311x_wdt_write,
343 .unlocked_ioctl = sch311x_wdt_ioctl,
344 .open = sch311x_wdt_open,
345 .release = sch311x_wdt_close,
348 static struct miscdevice sch311x_wdt_miscdev = {
349 .minor = WATCHDOG_MINOR,
351 .fops = &sch311x_wdt_fops,
355 * Init & exit routines
358 static int __devinit sch311x_wdt_probe(struct platform_device *pdev)
360 struct device *dev = &pdev->dev;
364 spin_lock_init(&sch311x_wdt_data.io_lock);
366 if (!request_region(sch311x_wdt_data.runtime_reg + RESGEN, 1,
368 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
369 sch311x_wdt_data.runtime_reg + RESGEN,
370 sch311x_wdt_data.runtime_reg + RESGEN);
375 if (!request_region(sch311x_wdt_data.runtime_reg + GP60, 1, DRV_NAME)) {
376 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
377 sch311x_wdt_data.runtime_reg + GP60,
378 sch311x_wdt_data.runtime_reg + GP60);
380 goto exit_release_region;
383 if (!request_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4,
385 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
386 sch311x_wdt_data.runtime_reg + WDT_TIME_OUT,
387 sch311x_wdt_data.runtime_reg + WDT_CTRL);
389 goto exit_release_region2;
392 /* Make sure that the watchdog is not running */
395 /* Disable keyboard and mouse interaction and interrupt */
396 /* -- Watchdog timer configuration --
398 * Bit 1 Keyboard enable: 0* = No Reset, 1 = Reset WDT upon KBD Intr.
399 * Bit 2 Mouse enable: 0* = No Reset, 1 = Reset WDT upon Mouse Intr
401 * Bit 4-7 WDT Interrupt Mapping: (0000* = Disabled,
402 * 0001=IRQ1, 0010=(Invalid), 0011=IRQ3 to 1111=IRQ15)
404 outb(0, sch311x_wdt_data.runtime_reg + WDT_CFG);
406 /* Check that the heartbeat value is within it's range ;
407 * if not reset to the default */
408 if (sch311x_wdt_set_heartbeat(timeout)) {
409 sch311x_wdt_set_heartbeat(WATCHDOG_TIMEOUT);
410 dev_info(dev, "timeout value must be 1<=x<=15300, using %d\n",
414 /* Get status at boot */
415 sch311x_wdt_get_status(&sch311x_wdt_data.boot_status);
417 /* enable watchdog */
418 /* -- Reset Generator --
419 * Bit 0 Enable Watchdog Timer Generation: 0* = Enabled, 1 = Disabled
420 * Bit 1 Thermtrip Source Select: O* = No Source, 1 = Source
421 * Bit 2 WDT2_CTL: WDT input bit
424 outb(0, sch311x_wdt_data.runtime_reg + RESGEN);
425 val = therm_trip ? 0x06 : 0x04;
426 outb(val, sch311x_wdt_data.runtime_reg + RESGEN);
428 sch311x_wdt_miscdev.parent = dev;
430 err = misc_register(&sch311x_wdt_miscdev);
432 dev_err(dev, "cannot register miscdev on minor=%d (err=%d)\n",
433 WATCHDOG_MINOR, err);
434 goto exit_release_region3;
438 "SMSC SCH311x WDT initialized. timeout=%d sec (nowayout=%d)\n",
443 exit_release_region3:
444 release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4);
445 exit_release_region2:
446 release_region(sch311x_wdt_data.runtime_reg + GP60, 1);
448 release_region(sch311x_wdt_data.runtime_reg + RESGEN, 1);
449 sch311x_wdt_data.runtime_reg = 0;
454 static int __devexit sch311x_wdt_remove(struct platform_device *pdev)
456 /* Stop the timer before we leave */
461 misc_deregister(&sch311x_wdt_miscdev);
462 release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4);
463 release_region(sch311x_wdt_data.runtime_reg + GP60, 1);
464 release_region(sch311x_wdt_data.runtime_reg + RESGEN, 1);
465 sch311x_wdt_data.runtime_reg = 0;
469 static void sch311x_wdt_shutdown(struct platform_device *dev)
471 /* Turn the WDT off if we have a soft shutdown */
475 #define sch311x_wdt_suspend NULL
476 #define sch311x_wdt_resume NULL
478 static struct platform_driver sch311x_wdt_driver = {
479 .probe = sch311x_wdt_probe,
480 .remove = __devexit_p(sch311x_wdt_remove),
481 .shutdown = sch311x_wdt_shutdown,
482 .suspend = sch311x_wdt_suspend,
483 .resume = sch311x_wdt_resume,
485 .owner = THIS_MODULE,
490 static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
493 unsigned short base_addr;
494 unsigned char dev_id;
496 sch311x_sio_enter(sio_config_port);
498 /* Check device ID. We currently know about:
499 * SCH3112 (0x7c), SCH3114 (0x7d), and SCH3116 (0x7f). */
500 reg = force_id ? force_id : sch311x_sio_inb(sio_config_port, 0x20);
501 if (!(reg == 0x7c || reg == 0x7d || reg == 0x7f)) {
505 dev_id = reg == 0x7c ? 2 : reg == 0x7d ? 4 : 6;
507 /* Select logical device A (runtime registers) */
508 sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
510 /* Check if Logical Device Register is currently active */
511 if (sch311x_sio_inb(sio_config_port, 0x30) && 0x01 == 0)
512 printk(KERN_INFO PFX "Seems that LDN 0x0a is not active...\n");
514 /* Get the base address of the runtime registers */
515 base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
516 sch311x_sio_inb(sio_config_port, 0x61);
518 printk(KERN_ERR PFX "Base address not set.\n");
524 printk(KERN_INFO PFX "Found an SMSC SCH311%d chip at 0x%04x\n",
528 sch311x_sio_exit(sio_config_port);
532 static int __init sch311x_wdt_init(void)
534 int err, i, found = 0;
535 unsigned short addr = 0;
537 for (i = 0; !found && sch311x_ioports[i]; i++)
538 if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
544 sch311x_wdt_data.runtime_reg = addr;
546 err = platform_driver_register(&sch311x_wdt_driver);
550 sch311x_wdt_pdev = platform_device_register_simple(DRV_NAME, addr,
553 if (IS_ERR(sch311x_wdt_pdev)) {
554 err = PTR_ERR(sch311x_wdt_pdev);
555 goto unreg_platform_driver;
560 unreg_platform_driver:
561 platform_driver_unregister(&sch311x_wdt_driver);
565 static void __exit sch311x_wdt_exit(void)
567 platform_device_unregister(sch311x_wdt_pdev);
568 platform_driver_unregister(&sch311x_wdt_driver);
571 module_init(sch311x_wdt_init);
572 module_exit(sch311x_wdt_exit);
574 MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
575 MODULE_DESCRIPTION("SMSC SCH311x WatchDog Timer Driver");
576 MODULE_LICENSE("GPL");
577 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);