ARM: dts: add 'dr_mode' property to hsotg devices for exynos boards
[linux/fpc-iii.git] / drivers / watchdog / sch311x_wdt.c
blob43d0cbb7ba0b9dfe8c662df42332c212f8997932
1 /*
2 * sch311x_wdt.c - Driver for the SCH311x Super-I/O chips
3 * integrated watchdog.
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, ...
21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23 /* Includes */
24 #include <linux/module.h> /* For module specific items */
25 #include <linux/moduleparam.h> /* For new moduleparam's */
26 #include <linux/types.h> /* For standard types (like size_t) */
27 #include <linux/errno.h> /* For the -ENODEV/... values */
28 #include <linux/kernel.h> /* For printk/... */
29 #include <linux/miscdevice.h> /* For struct miscdevice */
30 #include <linux/watchdog.h> /* For the watchdog specific items */
31 #include <linux/init.h> /* For __init/__exit/... */
32 #include <linux/fs.h> /* For file operations */
33 #include <linux/platform_device.h> /* For platform_driver framework */
34 #include <linux/ioport.h> /* For io-port access */
35 #include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
36 #include <linux/uaccess.h> /* For copy_to_user/put_user/... */
37 #include <linux/io.h> /* For inb/outb/... */
39 /* Module and version information */
40 #define DRV_NAME "sch311x_wdt"
42 /* Runtime registers */
43 #define GP60 0x47
44 #define WDT_TIME_OUT 0x65
45 #define WDT_VAL 0x66
46 #define WDT_CFG 0x67
47 #define WDT_CTRL 0x68
49 /* internal variables */
50 static unsigned long sch311x_wdt_is_open;
51 static char sch311x_wdt_expect_close;
52 static struct platform_device *sch311x_wdt_pdev;
54 static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e, 0x00 };
56 static struct { /* The devices private data */
57 /* the Runtime Register base address */
58 unsigned short runtime_reg;
59 /* The card's boot status */
60 int boot_status;
61 /* the lock for io operations */
62 spinlock_t io_lock;
63 } sch311x_wdt_data;
65 /* Module load parameters */
66 static unsigned short force_id;
67 module_param(force_id, ushort, 0);
68 MODULE_PARM_DESC(force_id, "Override the detected device ID");
70 #define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
71 static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
72 module_param(timeout, int, 0);
73 MODULE_PARM_DESC(timeout,
74 "Watchdog timeout in seconds. 1<= timeout <=15300, default="
75 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
77 static bool nowayout = WATCHDOG_NOWAYOUT;
78 module_param(nowayout, bool, 0);
79 MODULE_PARM_DESC(nowayout,
80 "Watchdog cannot be stopped once started (default="
81 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
84 * Super-IO functions
87 static inline void sch311x_sio_enter(int sio_config_port)
89 outb(0x55, sio_config_port);
92 static inline void sch311x_sio_exit(int sio_config_port)
94 outb(0xaa, sio_config_port);
97 static inline int sch311x_sio_inb(int sio_config_port, int reg)
99 outb(reg, sio_config_port);
100 return inb(sio_config_port + 1);
103 static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
105 outb(reg, sio_config_port);
106 outb(val, sio_config_port + 1);
110 * Watchdog Operations
113 static void sch311x_wdt_set_timeout(int t)
115 unsigned char timeout_unit = 0x80;
117 /* When new timeout is bigger then 255 seconds, we will use minutes */
118 if (t > 255) {
119 timeout_unit = 0;
120 t /= 60;
123 /* -- Watchdog Timeout --
124 * Bit 0-6 (Reserved)
125 * Bit 7 WDT Time-out Value Units Select
126 * (0 = Minutes, 1 = Seconds)
128 outb(timeout_unit, sch311x_wdt_data.runtime_reg + WDT_TIME_OUT);
130 /* -- Watchdog Timer Time-out Value --
131 * Bit 0-7 Binary coded units (0=Disabled, 1..255)
133 outb(t, sch311x_wdt_data.runtime_reg + WDT_VAL);
136 static void sch311x_wdt_start(void)
138 unsigned char t;
140 spin_lock(&sch311x_wdt_data.io_lock);
142 /* set watchdog's timeout */
143 sch311x_wdt_set_timeout(timeout);
144 /* enable the watchdog */
145 /* -- General Purpose I/O Bit 6.0 --
146 * Bit 0, In/Out: 0 = Output, 1 = Input
147 * Bit 1, Polarity: 0 = No Invert, 1 = Invert
148 * Bit 2-3, Function select: 00 = GPI/O, 01 = LED1, 11 = WDT,
149 * 10 = Either Edge Triggered Intr.4
150 * Bit 4-6 (Reserved)
151 * Bit 7, Output Type: 0 = Push Pull Bit, 1 = Open Drain
153 t = inb(sch311x_wdt_data.runtime_reg + GP60);
154 outb((t & ~0x0d) | 0x0c, sch311x_wdt_data.runtime_reg + GP60);
156 spin_unlock(&sch311x_wdt_data.io_lock);
160 static void sch311x_wdt_stop(void)
162 unsigned char t;
164 spin_lock(&sch311x_wdt_data.io_lock);
166 /* stop the watchdog */
167 t = inb(sch311x_wdt_data.runtime_reg + GP60);
168 outb((t & ~0x0d) | 0x01, sch311x_wdt_data.runtime_reg + GP60);
169 /* disable timeout by setting it to 0 */
170 sch311x_wdt_set_timeout(0);
172 spin_unlock(&sch311x_wdt_data.io_lock);
175 static void sch311x_wdt_keepalive(void)
177 spin_lock(&sch311x_wdt_data.io_lock);
178 sch311x_wdt_set_timeout(timeout);
179 spin_unlock(&sch311x_wdt_data.io_lock);
182 static int sch311x_wdt_set_heartbeat(int t)
184 if (t < 1 || t > (255*60))
185 return -EINVAL;
187 /* When new timeout is bigger then 255 seconds,
188 * we will round up to minutes (with a max of 255) */
189 if (t > 255)
190 t = (((t - 1) / 60) + 1) * 60;
192 timeout = t;
193 return 0;
196 static void sch311x_wdt_get_status(int *status)
198 unsigned char new_status;
200 *status = 0;
202 spin_lock(&sch311x_wdt_data.io_lock);
204 /* -- Watchdog timer control --
205 * Bit 0 Status Bit: 0 = Timer counting, 1 = Timeout occurred
206 * Bit 1 Reserved
207 * Bit 2 Force Timeout: 1 = Forces WD timeout event (self-cleaning)
208 * Bit 3 P20 Force Timeout enabled:
209 * 0 = P20 activity does not generate the WD timeout event
210 * 1 = P20 Allows rising edge of P20, from the keyboard
211 * controller, to force the WD timeout event.
212 * Bit 4-7 Reserved
214 new_status = inb(sch311x_wdt_data.runtime_reg + WDT_CTRL);
215 if (new_status & 0x01)
216 *status |= WDIOF_CARDRESET;
218 spin_unlock(&sch311x_wdt_data.io_lock);
222 * /dev/watchdog handling
225 static ssize_t sch311x_wdt_write(struct file *file, const char __user *buf,
226 size_t count, loff_t *ppos)
228 if (count) {
229 if (!nowayout) {
230 size_t i;
232 sch311x_wdt_expect_close = 0;
234 for (i = 0; i != count; i++) {
235 char c;
236 if (get_user(c, buf + i))
237 return -EFAULT;
238 if (c == 'V')
239 sch311x_wdt_expect_close = 42;
242 sch311x_wdt_keepalive();
244 return count;
247 static long sch311x_wdt_ioctl(struct file *file, unsigned int cmd,
248 unsigned long arg)
250 int status;
251 int new_timeout;
252 void __user *argp = (void __user *)arg;
253 int __user *p = argp;
254 static const struct watchdog_info ident = {
255 .options = WDIOF_KEEPALIVEPING |
256 WDIOF_SETTIMEOUT |
257 WDIOF_MAGICCLOSE,
258 .firmware_version = 1,
259 .identity = DRV_NAME,
262 switch (cmd) {
263 case WDIOC_GETSUPPORT:
264 if (copy_to_user(argp, &ident, sizeof(ident)))
265 return -EFAULT;
266 break;
268 case WDIOC_GETSTATUS:
270 sch311x_wdt_get_status(&status);
271 return put_user(status, p);
273 case WDIOC_GETBOOTSTATUS:
274 return put_user(sch311x_wdt_data.boot_status, p);
276 case WDIOC_SETOPTIONS:
278 int options, retval = -EINVAL;
280 if (get_user(options, p))
281 return -EFAULT;
282 if (options & WDIOS_DISABLECARD) {
283 sch311x_wdt_stop();
284 retval = 0;
286 if (options & WDIOS_ENABLECARD) {
287 sch311x_wdt_start();
288 retval = 0;
290 return retval;
292 case WDIOC_KEEPALIVE:
293 sch311x_wdt_keepalive();
294 break;
296 case WDIOC_SETTIMEOUT:
297 if (get_user(new_timeout, p))
298 return -EFAULT;
299 if (sch311x_wdt_set_heartbeat(new_timeout))
300 return -EINVAL;
301 sch311x_wdt_keepalive();
302 /* Fall */
303 case WDIOC_GETTIMEOUT:
304 return put_user(timeout, p);
305 default:
306 return -ENOTTY;
308 return 0;
311 static int sch311x_wdt_open(struct inode *inode, struct file *file)
313 if (test_and_set_bit(0, &sch311x_wdt_is_open))
314 return -EBUSY;
316 * Activate
318 sch311x_wdt_start();
319 return nonseekable_open(inode, file);
322 static int sch311x_wdt_close(struct inode *inode, struct file *file)
324 if (sch311x_wdt_expect_close == 42) {
325 sch311x_wdt_stop();
326 } else {
327 pr_crit("Unexpected close, not stopping watchdog!\n");
328 sch311x_wdt_keepalive();
330 clear_bit(0, &sch311x_wdt_is_open);
331 sch311x_wdt_expect_close = 0;
332 return 0;
336 * Kernel Interfaces
339 static const struct file_operations sch311x_wdt_fops = {
340 .owner = THIS_MODULE,
341 .llseek = no_llseek,
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,
350 .name = "watchdog",
351 .fops = &sch311x_wdt_fops,
355 * Init & exit routines
358 static int sch311x_wdt_probe(struct platform_device *pdev)
360 struct device *dev = &pdev->dev;
361 int err;
363 spin_lock_init(&sch311x_wdt_data.io_lock);
365 if (!request_region(sch311x_wdt_data.runtime_reg + GP60, 1, DRV_NAME)) {
366 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
367 sch311x_wdt_data.runtime_reg + GP60,
368 sch311x_wdt_data.runtime_reg + GP60);
369 err = -EBUSY;
370 goto exit;
373 if (!request_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4,
374 DRV_NAME)) {
375 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
376 sch311x_wdt_data.runtime_reg + WDT_TIME_OUT,
377 sch311x_wdt_data.runtime_reg + WDT_CTRL);
378 err = -EBUSY;
379 goto exit_release_region;
382 /* Make sure that the watchdog is not running */
383 sch311x_wdt_stop();
385 /* Disable keyboard and mouse interaction and interrupt */
386 /* -- Watchdog timer configuration --
387 * Bit 0 Reserved
388 * Bit 1 Keyboard enable: 0* = No Reset, 1 = Reset WDT upon KBD Intr.
389 * Bit 2 Mouse enable: 0* = No Reset, 1 = Reset WDT upon Mouse Intr
390 * Bit 3 Reserved
391 * Bit 4-7 WDT Interrupt Mapping: (0000* = Disabled,
392 * 0001=IRQ1, 0010=(Invalid), 0011=IRQ3 to 1111=IRQ15)
394 outb(0, sch311x_wdt_data.runtime_reg + WDT_CFG);
396 /* Check that the heartbeat value is within it's range ;
397 * if not reset to the default */
398 if (sch311x_wdt_set_heartbeat(timeout)) {
399 sch311x_wdt_set_heartbeat(WATCHDOG_TIMEOUT);
400 dev_info(dev, "timeout value must be 1<=x<=15300, using %d\n",
401 timeout);
404 /* Get status at boot */
405 sch311x_wdt_get_status(&sch311x_wdt_data.boot_status);
407 sch311x_wdt_miscdev.parent = dev;
409 err = misc_register(&sch311x_wdt_miscdev);
410 if (err != 0) {
411 dev_err(dev, "cannot register miscdev on minor=%d (err=%d)\n",
412 WATCHDOG_MINOR, err);
413 goto exit_release_region2;
416 dev_info(dev,
417 "SMSC SCH311x WDT initialized. timeout=%d sec (nowayout=%d)\n",
418 timeout, nowayout);
420 return 0;
422 exit_release_region2:
423 release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4);
424 exit_release_region:
425 release_region(sch311x_wdt_data.runtime_reg + GP60, 1);
426 sch311x_wdt_data.runtime_reg = 0;
427 exit:
428 return err;
431 static int sch311x_wdt_remove(struct platform_device *pdev)
433 /* Stop the timer before we leave */
434 if (!nowayout)
435 sch311x_wdt_stop();
437 /* Deregister */
438 misc_deregister(&sch311x_wdt_miscdev);
439 release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4);
440 release_region(sch311x_wdt_data.runtime_reg + GP60, 1);
441 sch311x_wdt_data.runtime_reg = 0;
442 return 0;
445 static void sch311x_wdt_shutdown(struct platform_device *dev)
447 /* Turn the WDT off if we have a soft shutdown */
448 sch311x_wdt_stop();
451 static struct platform_driver sch311x_wdt_driver = {
452 .probe = sch311x_wdt_probe,
453 .remove = sch311x_wdt_remove,
454 .shutdown = sch311x_wdt_shutdown,
455 .driver = {
456 .name = DRV_NAME,
460 static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
462 int err = 0, reg;
463 unsigned short base_addr;
464 unsigned char dev_id;
466 sch311x_sio_enter(sio_config_port);
468 /* Check device ID. We currently know about:
469 * SCH3112 (0x7c), SCH3114 (0x7d), and SCH3116 (0x7f). */
470 reg = force_id ? force_id : sch311x_sio_inb(sio_config_port, 0x20);
471 if (!(reg == 0x7c || reg == 0x7d || reg == 0x7f)) {
472 err = -ENODEV;
473 goto exit;
475 dev_id = reg == 0x7c ? 2 : reg == 0x7d ? 4 : 6;
477 /* Select logical device A (runtime registers) */
478 sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
480 /* Check if Logical Device Register is currently active */
481 if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
482 pr_info("Seems that LDN 0x0a is not active...\n");
484 /* Get the base address of the runtime registers */
485 base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
486 sch311x_sio_inb(sio_config_port, 0x61);
487 if (!base_addr) {
488 pr_err("Base address not set\n");
489 err = -ENODEV;
490 goto exit;
492 *addr = base_addr;
494 pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);
496 exit:
497 sch311x_sio_exit(sio_config_port);
498 return err;
501 static int __init sch311x_wdt_init(void)
503 int err, i, found = 0;
504 unsigned short addr = 0;
506 for (i = 0; !found && sch311x_ioports[i]; i++)
507 if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
508 found++;
510 if (!found)
511 return -ENODEV;
513 sch311x_wdt_data.runtime_reg = addr;
515 err = platform_driver_register(&sch311x_wdt_driver);
516 if (err)
517 return err;
519 sch311x_wdt_pdev = platform_device_register_simple(DRV_NAME, addr,
520 NULL, 0);
522 if (IS_ERR(sch311x_wdt_pdev)) {
523 err = PTR_ERR(sch311x_wdt_pdev);
524 goto unreg_platform_driver;
527 return 0;
529 unreg_platform_driver:
530 platform_driver_unregister(&sch311x_wdt_driver);
531 return err;
534 static void __exit sch311x_wdt_exit(void)
536 platform_device_unregister(sch311x_wdt_pdev);
537 platform_driver_unregister(&sch311x_wdt_driver);
540 module_init(sch311x_wdt_init);
541 module_exit(sch311x_wdt_exit);
543 MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
544 MODULE_DESCRIPTION("SMSC SCH311x WatchDog Timer Driver");
545 MODULE_LICENSE("GPL");