1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * PC Watchdog Driver |
4 | * by Ken Hollis (khollis@bitgate.com) |
5 | * |
6 | * Permission granted from Simon Machell (smachell@berkprod.com) |
7 | * Written for the Linux Kernel, and GPLed by Ken Hollis |
8 | * |
9 | * 960107 Added request_region routines, modulized the whole thing. |
10 | * 960108 Fixed end-of-file pointer (Thanks to Dan Hollis), added |
11 | * WD_TIMEOUT define. |
12 | * 960216 Added eof marker on the file, and changed verbose messages. |
13 | * 960716 Made functional and cosmetic changes to the source for |
14 | * inclusion in Linux 2.0.x kernels, thanks to Alan Cox. |
15 | * 960717 Removed read/seek routines, replaced with ioctl. Also, added |
16 | * check_region command due to Alan's suggestion. |
17 | * 960821 Made changes to compile in newer 2.0.x kernels. Added |
18 | * "cold reboot sense" entry. |
19 | * 960825 Made a few changes to code, deleted some defines and made |
20 | * typedefs to replace them. Made heartbeat reset only available |
21 | * via ioctl, and removed the write routine. |
22 | * 960828 Added new items for PC Watchdog Rev.C card. |
23 | * 960829 Changed around all of the IOCTLs, added new features, |
24 | * added watchdog disable/re-enable routines. Added firmware |
25 | * version reporting. Added read routine for temperature. |
26 | * Removed some extra defines, added an autodetect Revision |
27 | * routine. |
28 | * 961006 Revised some documentation, fixed some cosmetic bugs. Made |
29 | * drivers to panic the system if it's overheating at bootup. |
30 | * 961118 Changed some verbiage on some of the output, tidied up |
31 | * code bits, and added compatibility to 2.1.x. |
32 | * 970912 Enabled board on open and disable on close. |
33 | * 971107 Took account of recent VFS changes (broke read). |
34 | * 971210 Disable board on initialisation in case board already ticking. |
35 | * 971222 Changed open/close for temperature handling |
36 | * Michael Meskes <meskes@debian.org>. |
37 | * 980112 Used minor numbers from include/linux/miscdevice.h |
38 | * 990403 Clear reset status after reading control status register in |
39 | * pcwd_showprevstate(). [Marc Boucher <marc@mbsi.ca>] |
40 | * 990605 Made changes to code to support Firmware 1.22a, added |
41 | * fairly useless proc entry. |
42 | * 990610 removed said useless proc code for the merge <alan> |
43 | * 000403 Removed last traces of proc code. <davej> |
44 | * 011214 Added nowayout module option to override |
45 | * CONFIG_WATCHDOG_NOWAYOUT <Matt_Domsch@dell.com> |
46 | * Added timeout module option to override default |
47 | */ |
48 | |
49 | /* |
50 | * A bells and whistles driver is available from http://www.pcwd.de/ |
51 | * More info available at http://www.berkprod.com/ or |
52 | * http://www.pcwatchdog.com/ |
53 | */ |
54 | |
55 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
56 | |
57 | #include <linux/module.h> /* For module specific items */ |
58 | #include <linux/moduleparam.h> /* For new moduleparam's */ |
59 | #include <linux/types.h> /* For standard types (like size_t) */ |
60 | #include <linux/errno.h> /* For the -ENODEV/... values */ |
61 | #include <linux/kernel.h> /* For printk/panic/... */ |
62 | #include <linux/delay.h> /* For mdelay function */ |
63 | #include <linux/timer.h> /* For timer related operations */ |
64 | #include <linux/jiffies.h> /* For jiffies stuff */ |
65 | #include <linux/miscdevice.h> /* For struct miscdevice */ |
66 | #include <linux/watchdog.h> /* For the watchdog specific items */ |
67 | #include <linux/reboot.h> /* For kernel_power_off() */ |
68 | #include <linux/init.h> /* For __init/__exit/... */ |
69 | #include <linux/fs.h> /* For file operations */ |
70 | #include <linux/isa.h> /* For isa devices */ |
71 | #include <linux/ioport.h> /* For io-port access */ |
72 | #include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */ |
73 | #include <linux/uaccess.h> /* For copy_to_user/put_user/... */ |
74 | #include <linux/io.h> /* For inb/outb/... */ |
75 | |
76 | /* Module and version information */ |
77 | #define WATCHDOG_VERSION "1.20" |
78 | #define WATCHDOG_DATE "18 Feb 2007" |
79 | #define WATCHDOG_DRIVER_NAME "ISA-PC Watchdog" |
80 | #define WATCHDOG_NAME "pcwd" |
81 | #define DRIVER_VERSION WATCHDOG_DRIVER_NAME " driver, v" WATCHDOG_VERSION "\n" |
82 | |
83 | /* |
84 | * It should be noted that PCWD_REVISION_B was removed because A and B |
85 | * are essentially the same types of card, with the exception that B |
86 | * has temperature reporting. Since I didn't receive a Rev.B card, |
87 | * the Rev.B card is not supported. (It's a good thing too, as they |
88 | * are no longer in production.) |
89 | */ |
90 | #define PCWD_REVISION_A 1 |
91 | #define PCWD_REVISION_C 2 |
92 | |
93 | /* |
94 | * These are the auto-probe addresses available. |
95 | * |
96 | * Revision A only uses ports 0x270 and 0x370. Revision C introduced 0x350. |
97 | * Revision A has an address range of 2 addresses, while Revision C has 4. |
98 | */ |
99 | #define PCWD_ISA_NR_CARDS 3 |
100 | static int pcwd_ioports[] = { 0x270, 0x350, 0x370, 0x000 }; |
101 | |
102 | /* |
103 | * These are the defines that describe the control status bits for the |
104 | * PCI-PC Watchdog card. |
105 | */ |
106 | /* Port 1 : Control Status #1 for the PC Watchdog card, revision A. */ |
107 | #define WD_WDRST 0x01 /* Previously reset state */ |
108 | #define WD_T110 0x02 /* Temperature overheat sense */ |
109 | #define WD_HRTBT 0x04 /* Heartbeat sense */ |
110 | #define WD_RLY2 0x08 /* External relay triggered */ |
111 | #define WD_SRLY2 0x80 /* Software external relay triggered */ |
112 | /* Port 1 : Control Status #1 for the PC Watchdog card, revision C. */ |
113 | #define WD_REVC_WTRP 0x01 /* Watchdog Trip status */ |
114 | #define WD_REVC_HRBT 0x02 /* Watchdog Heartbeat */ |
115 | #define WD_REVC_TTRP 0x04 /* Temperature Trip status */ |
116 | #define WD_REVC_RL2A 0x08 /* Relay 2 activated by |
117 | on-board processor */ |
118 | #define WD_REVC_RL1A 0x10 /* Relay 1 active */ |
119 | #define WD_REVC_R2DS 0x40 /* Relay 2 disable */ |
120 | #define WD_REVC_RLY2 0x80 /* Relay 2 activated? */ |
121 | /* Port 2 : Control Status #2 */ |
122 | #define WD_WDIS 0x10 /* Watchdog Disabled */ |
123 | #define WD_ENTP 0x20 /* Watchdog Enable Temperature Trip */ |
124 | #define WD_SSEL 0x40 /* Watchdog Switch Select |
125 | (1:SW1 <-> 0:SW2) */ |
126 | #define WD_WCMD 0x80 /* Watchdog Command Mode */ |
127 | |
128 | /* max. time we give an ISA watchdog card to process a command */ |
129 | /* 500ms for each 4 bit response (according to spec.) */ |
130 | #define ISA_COMMAND_TIMEOUT 1000 |
131 | |
132 | /* Watchdog's internal commands */ |
133 | #define CMD_ISA_IDLE 0x00 |
134 | #define CMD_ISA_VERSION_INTEGER 0x01 |
135 | #define CMD_ISA_VERSION_TENTH 0x02 |
136 | #define CMD_ISA_VERSION_HUNDRETH 0x03 |
137 | #define CMD_ISA_VERSION_MINOR 0x04 |
138 | #define CMD_ISA_SWITCH_SETTINGS 0x05 |
139 | #define CMD_ISA_RESET_PC 0x06 |
140 | #define CMD_ISA_ARM_0 0x07 |
141 | #define CMD_ISA_ARM_30 0x08 |
142 | #define CMD_ISA_ARM_60 0x09 |
143 | #define CMD_ISA_DELAY_TIME_2SECS 0x0A |
144 | #define CMD_ISA_DELAY_TIME_4SECS 0x0B |
145 | #define CMD_ISA_DELAY_TIME_8SECS 0x0C |
146 | #define CMD_ISA_RESET_RELAYS 0x0D |
147 | |
148 | /* Watchdog's Dip Switch heartbeat values */ |
149 | static const int heartbeat_tbl[] = { |
150 | 20, /* OFF-OFF-OFF = 20 Sec */ |
151 | 40, /* OFF-OFF-ON = 40 Sec */ |
152 | 60, /* OFF-ON-OFF = 1 Min */ |
153 | 300, /* OFF-ON-ON = 5 Min */ |
154 | 600, /* ON-OFF-OFF = 10 Min */ |
155 | 1800, /* ON-OFF-ON = 30 Min */ |
156 | 3600, /* ON-ON-OFF = 1 Hour */ |
157 | 7200, /* ON-ON-ON = 2 hour */ |
158 | }; |
159 | |
160 | /* |
161 | * We are using an kernel timer to do the pinging of the watchdog |
162 | * every ~500ms. We try to set the internal heartbeat of the |
163 | * watchdog to 2 ms. |
164 | */ |
165 | |
166 | #define WDT_INTERVAL (HZ/2+1) |
167 | |
168 | /* We can only use 1 card due to the /dev/watchdog restriction */ |
169 | static int cards_found; |
170 | |
171 | /* internal variables */ |
172 | static unsigned long open_allowed; |
173 | static char expect_close; |
174 | static int temp_panic; |
175 | |
176 | /* this is private data for each ISA-PC watchdog card */ |
177 | static struct { |
178 | char fw_ver_str[6]; /* The cards firmware version */ |
179 | int revision; /* The card's revision */ |
180 | int supports_temp; /* Whether or not the card has |
181 | a temperature device */ |
182 | int command_mode; /* Whether or not the card is in |
183 | command mode */ |
184 | int boot_status; /* The card's boot status */ |
185 | int io_addr; /* The cards I/O address */ |
186 | spinlock_t io_lock; /* the lock for io operations */ |
187 | struct timer_list timer; /* The timer that pings the watchdog */ |
188 | unsigned long next_heartbeat; /* the next_heartbeat for the timer */ |
189 | } pcwd_private; |
190 | |
191 | /* module parameters */ |
192 | #define QUIET 0 /* Default */ |
193 | #define VERBOSE 1 /* Verbose */ |
194 | #define DEBUG 2 /* print fancy stuff too */ |
195 | static int debug = QUIET; |
196 | module_param(debug, int, 0); |
197 | MODULE_PARM_DESC(debug, |
198 | "Debug level: 0=Quiet, 1=Verbose, 2=Debug (default=0)" ); |
199 | |
200 | /* default heartbeat = delay-time from dip-switches */ |
201 | #define WATCHDOG_HEARTBEAT 0 |
202 | static int heartbeat = WATCHDOG_HEARTBEAT; |
203 | module_param(heartbeat, int, 0); |
204 | MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. " |
205 | "(2 <= heartbeat <= 7200 or 0=delay-time from dip-switches, default=" |
206 | __MODULE_STRING(WATCHDOG_HEARTBEAT) ")" ); |
207 | |
208 | static bool nowayout = WATCHDOG_NOWAYOUT; |
209 | module_param(nowayout, bool, 0); |
210 | MODULE_PARM_DESC(nowayout, |
211 | "Watchdog cannot be stopped once started (default=" |
212 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")" ); |
213 | |
214 | /* |
215 | * Internal functions |
216 | */ |
217 | |
218 | static int send_isa_command(int cmd) |
219 | { |
220 | int i; |
221 | int control_status; |
222 | int port0, last_port0; /* Double read for stabilising */ |
223 | |
224 | if (debug >= DEBUG) |
225 | pr_debug("sending following data cmd=0x%02x\n" , cmd); |
226 | |
227 | /* The WCMD bit must be 1 and the command is only 4 bits in size */ |
228 | control_status = (cmd & 0x0F) | WD_WCMD; |
229 | outb_p(value: control_status, port: pcwd_private.io_addr + 2); |
230 | udelay(ISA_COMMAND_TIMEOUT); |
231 | |
232 | port0 = inb_p(port: pcwd_private.io_addr); |
233 | for (i = 0; i < 25; ++i) { |
234 | last_port0 = port0; |
235 | port0 = inb_p(port: pcwd_private.io_addr); |
236 | |
237 | if (port0 == last_port0) |
238 | break; /* Data is stable */ |
239 | |
240 | udelay(250); |
241 | } |
242 | |
243 | if (debug >= DEBUG) |
244 | pr_debug("received following data for cmd=0x%02x: port0=0x%02x last_port0=0x%02x\n" , |
245 | cmd, port0, last_port0); |
246 | |
247 | return port0; |
248 | } |
249 | |
250 | static int set_command_mode(void) |
251 | { |
252 | int i, found = 0, count = 0; |
253 | |
254 | /* Set the card into command mode */ |
255 | spin_lock(lock: &pcwd_private.io_lock); |
256 | while ((!found) && (count < 3)) { |
257 | i = send_isa_command(CMD_ISA_IDLE); |
258 | |
259 | if (i == 0x00) |
260 | found = 1; |
261 | else if (i == 0xF3) { |
262 | /* Card does not like what we've done to it */ |
263 | outb_p(value: 0x00, port: pcwd_private.io_addr + 2); |
264 | udelay(1200); /* Spec says wait 1ms */ |
265 | outb_p(value: 0x00, port: pcwd_private.io_addr + 2); |
266 | udelay(ISA_COMMAND_TIMEOUT); |
267 | } |
268 | count++; |
269 | } |
270 | spin_unlock(lock: &pcwd_private.io_lock); |
271 | pcwd_private.command_mode = found; |
272 | |
273 | if (debug >= DEBUG) |
274 | pr_debug("command_mode=%d\n" , pcwd_private.command_mode); |
275 | |
276 | return found; |
277 | } |
278 | |
279 | static void unset_command_mode(void) |
280 | { |
281 | /* Set the card into normal mode */ |
282 | spin_lock(lock: &pcwd_private.io_lock); |
283 | outb_p(value: 0x00, port: pcwd_private.io_addr + 2); |
284 | udelay(ISA_COMMAND_TIMEOUT); |
285 | spin_unlock(lock: &pcwd_private.io_lock); |
286 | |
287 | pcwd_private.command_mode = 0; |
288 | |
289 | if (debug >= DEBUG) |
290 | pr_debug("command_mode=%d\n" , pcwd_private.command_mode); |
291 | } |
292 | |
293 | static inline void pcwd_check_temperature_support(void) |
294 | { |
295 | if (inb(port: pcwd_private.io_addr) != 0xF0) |
296 | pcwd_private.supports_temp = 1; |
297 | } |
298 | |
299 | static inline void pcwd_get_firmware(void) |
300 | { |
301 | int one, ten, hund, minor; |
302 | |
303 | strcpy(p: pcwd_private.fw_ver_str, q: "ERROR" ); |
304 | |
305 | if (set_command_mode()) { |
306 | one = send_isa_command(CMD_ISA_VERSION_INTEGER); |
307 | ten = send_isa_command(CMD_ISA_VERSION_TENTH); |
308 | hund = send_isa_command(CMD_ISA_VERSION_HUNDRETH); |
309 | minor = send_isa_command(CMD_ISA_VERSION_MINOR); |
310 | sprintf(buf: pcwd_private.fw_ver_str, fmt: "%c.%c%c%c" , |
311 | one, ten, hund, minor); |
312 | } |
313 | unset_command_mode(); |
314 | |
315 | return; |
316 | } |
317 | |
318 | static inline int pcwd_get_option_switches(void) |
319 | { |
320 | int option_switches = 0; |
321 | |
322 | if (set_command_mode()) { |
323 | /* Get switch settings */ |
324 | option_switches = send_isa_command(CMD_ISA_SWITCH_SETTINGS); |
325 | } |
326 | |
327 | unset_command_mode(); |
328 | return option_switches; |
329 | } |
330 | |
331 | static void pcwd_show_card_info(void) |
332 | { |
333 | int option_switches; |
334 | |
335 | /* Get some extra info from the hardware (in command/debug/diag mode) */ |
336 | if (pcwd_private.revision == PCWD_REVISION_A) |
337 | pr_info("ISA-PC Watchdog (REV.A) detected at port 0x%04x\n" , |
338 | pcwd_private.io_addr); |
339 | else if (pcwd_private.revision == PCWD_REVISION_C) { |
340 | pcwd_get_firmware(); |
341 | pr_info("ISA-PC Watchdog (REV.C) detected at port 0x%04x (Firmware version: %s)\n" , |
342 | pcwd_private.io_addr, pcwd_private.fw_ver_str); |
343 | option_switches = pcwd_get_option_switches(); |
344 | pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n" , |
345 | option_switches, |
346 | ((option_switches & 0x10) ? "ON" : "OFF" ), |
347 | ((option_switches & 0x08) ? "ON" : "OFF" )); |
348 | |
349 | /* Reprogram internal heartbeat to 2 seconds */ |
350 | if (set_command_mode()) { |
351 | send_isa_command(CMD_ISA_DELAY_TIME_2SECS); |
352 | unset_command_mode(); |
353 | } |
354 | } |
355 | |
356 | if (pcwd_private.supports_temp) |
357 | pr_info("Temperature Option Detected\n" ); |
358 | |
359 | if (pcwd_private.boot_status & WDIOF_CARDRESET) |
360 | pr_info("Previous reboot was caused by the card\n" ); |
361 | |
362 | if (pcwd_private.boot_status & WDIOF_OVERHEAT) { |
363 | pr_emerg("Card senses a CPU Overheat. Panicking!\n" ); |
364 | pr_emerg("CPU Overheat\n" ); |
365 | } |
366 | |
367 | if (pcwd_private.boot_status == 0) |
368 | pr_info("No previous trip detected - Cold boot or reset\n" ); |
369 | } |
370 | |
371 | static void pcwd_timer_ping(struct timer_list *unused) |
372 | { |
373 | int wdrst_stat; |
374 | |
375 | /* If we got a heartbeat pulse within the WDT_INTERVAL |
376 | * we agree to ping the WDT */ |
377 | if (time_before(jiffies, pcwd_private.next_heartbeat)) { |
378 | /* Ping the watchdog */ |
379 | spin_lock(lock: &pcwd_private.io_lock); |
380 | if (pcwd_private.revision == PCWD_REVISION_A) { |
381 | /* Rev A cards are reset by setting the |
382 | WD_WDRST bit in register 1 */ |
383 | wdrst_stat = inb_p(port: pcwd_private.io_addr); |
384 | wdrst_stat &= 0x0F; |
385 | wdrst_stat |= WD_WDRST; |
386 | |
387 | outb_p(value: wdrst_stat, port: pcwd_private.io_addr + 1); |
388 | } else { |
389 | /* Re-trigger watchdog by writing to port 0 */ |
390 | outb_p(value: 0x00, port: pcwd_private.io_addr); |
391 | } |
392 | |
393 | /* Re-set the timer interval */ |
394 | mod_timer(timer: &pcwd_private.timer, expires: jiffies + WDT_INTERVAL); |
395 | |
396 | spin_unlock(lock: &pcwd_private.io_lock); |
397 | } else { |
398 | pr_warn("Heartbeat lost! Will not ping the watchdog\n" ); |
399 | } |
400 | } |
401 | |
402 | static int pcwd_start(void) |
403 | { |
404 | int stat_reg; |
405 | |
406 | pcwd_private.next_heartbeat = jiffies + (heartbeat * HZ); |
407 | |
408 | /* Start the timer */ |
409 | mod_timer(timer: &pcwd_private.timer, expires: jiffies + WDT_INTERVAL); |
410 | |
411 | /* Enable the port */ |
412 | if (pcwd_private.revision == PCWD_REVISION_C) { |
413 | spin_lock(lock: &pcwd_private.io_lock); |
414 | outb_p(value: 0x00, port: pcwd_private.io_addr + 3); |
415 | udelay(ISA_COMMAND_TIMEOUT); |
416 | stat_reg = inb_p(port: pcwd_private.io_addr + 2); |
417 | spin_unlock(lock: &pcwd_private.io_lock); |
418 | if (stat_reg & WD_WDIS) { |
419 | pr_info("Could not start watchdog\n" ); |
420 | return -EIO; |
421 | } |
422 | } |
423 | |
424 | if (debug >= VERBOSE) |
425 | pr_debug("Watchdog started\n" ); |
426 | |
427 | return 0; |
428 | } |
429 | |
430 | static int pcwd_stop(void) |
431 | { |
432 | int stat_reg; |
433 | |
434 | /* Stop the timer */ |
435 | del_timer(timer: &pcwd_private.timer); |
436 | |
437 | /* Disable the board */ |
438 | if (pcwd_private.revision == PCWD_REVISION_C) { |
439 | spin_lock(lock: &pcwd_private.io_lock); |
440 | outb_p(value: 0xA5, port: pcwd_private.io_addr + 3); |
441 | udelay(ISA_COMMAND_TIMEOUT); |
442 | outb_p(value: 0xA5, port: pcwd_private.io_addr + 3); |
443 | udelay(ISA_COMMAND_TIMEOUT); |
444 | stat_reg = inb_p(port: pcwd_private.io_addr + 2); |
445 | spin_unlock(lock: &pcwd_private.io_lock); |
446 | if ((stat_reg & WD_WDIS) == 0) { |
447 | pr_info("Could not stop watchdog\n" ); |
448 | return -EIO; |
449 | } |
450 | } |
451 | |
452 | if (debug >= VERBOSE) |
453 | pr_debug("Watchdog stopped\n" ); |
454 | |
455 | return 0; |
456 | } |
457 | |
458 | static int pcwd_keepalive(void) |
459 | { |
460 | /* user land ping */ |
461 | pcwd_private.next_heartbeat = jiffies + (heartbeat * HZ); |
462 | |
463 | if (debug >= DEBUG) |
464 | pr_debug("Watchdog keepalive signal send\n" ); |
465 | |
466 | return 0; |
467 | } |
468 | |
469 | static int pcwd_set_heartbeat(int t) |
470 | { |
471 | if (t < 2 || t > 7200) /* arbitrary upper limit */ |
472 | return -EINVAL; |
473 | |
474 | heartbeat = t; |
475 | |
476 | if (debug >= VERBOSE) |
477 | pr_debug("New heartbeat: %d\n" , heartbeat); |
478 | |
479 | return 0; |
480 | } |
481 | |
482 | static int pcwd_get_status(int *status) |
483 | { |
484 | int control_status; |
485 | |
486 | *status = 0; |
487 | spin_lock(lock: &pcwd_private.io_lock); |
488 | if (pcwd_private.revision == PCWD_REVISION_A) |
489 | /* Rev A cards return status information from |
490 | * the base register, which is used for the |
491 | * temperature in other cards. */ |
492 | control_status = inb(port: pcwd_private.io_addr); |
493 | else { |
494 | /* Rev C cards return card status in the base |
495 | * address + 1 register. And use different bits |
496 | * to indicate a card initiated reset, and an |
497 | * over-temperature condition. And the reboot |
498 | * status can be reset. */ |
499 | control_status = inb(port: pcwd_private.io_addr + 1); |
500 | } |
501 | spin_unlock(lock: &pcwd_private.io_lock); |
502 | |
503 | if (pcwd_private.revision == PCWD_REVISION_A) { |
504 | if (control_status & WD_WDRST) |
505 | *status |= WDIOF_CARDRESET; |
506 | |
507 | if (control_status & WD_T110) { |
508 | *status |= WDIOF_OVERHEAT; |
509 | if (temp_panic) { |
510 | pr_info("Temperature overheat trip!\n" ); |
511 | kernel_power_off(); |
512 | } |
513 | } |
514 | } else { |
515 | if (control_status & WD_REVC_WTRP) |
516 | *status |= WDIOF_CARDRESET; |
517 | |
518 | if (control_status & WD_REVC_TTRP) { |
519 | *status |= WDIOF_OVERHEAT; |
520 | if (temp_panic) { |
521 | pr_info("Temperature overheat trip!\n" ); |
522 | kernel_power_off(); |
523 | } |
524 | } |
525 | } |
526 | |
527 | return 0; |
528 | } |
529 | |
530 | static int pcwd_clear_status(void) |
531 | { |
532 | int control_status; |
533 | |
534 | if (pcwd_private.revision == PCWD_REVISION_C) { |
535 | spin_lock(lock: &pcwd_private.io_lock); |
536 | |
537 | if (debug >= VERBOSE) |
538 | pr_info("clearing watchdog trip status\n" ); |
539 | |
540 | control_status = inb_p(port: pcwd_private.io_addr + 1); |
541 | |
542 | if (debug >= DEBUG) { |
543 | pr_debug("status was: 0x%02x\n" , control_status); |
544 | pr_debug("sending: 0x%02x\n" , |
545 | (control_status & WD_REVC_R2DS)); |
546 | } |
547 | |
548 | /* clear reset status & Keep Relay 2 disable state as it is */ |
549 | outb_p(value: (control_status & WD_REVC_R2DS), |
550 | port: pcwd_private.io_addr + 1); |
551 | |
552 | spin_unlock(lock: &pcwd_private.io_lock); |
553 | } |
554 | return 0; |
555 | } |
556 | |
557 | static int pcwd_get_temperature(int *temperature) |
558 | { |
559 | /* check that port 0 gives temperature info and no command results */ |
560 | if (pcwd_private.command_mode) |
561 | return -1; |
562 | |
563 | *temperature = 0; |
564 | if (!pcwd_private.supports_temp) |
565 | return -ENODEV; |
566 | |
567 | /* |
568 | * Convert celsius to fahrenheit, since this was |
569 | * the decided 'standard' for this return value. |
570 | */ |
571 | spin_lock(lock: &pcwd_private.io_lock); |
572 | *temperature = ((inb(port: pcwd_private.io_addr)) * 9 / 5) + 32; |
573 | spin_unlock(lock: &pcwd_private.io_lock); |
574 | |
575 | if (debug >= DEBUG) { |
576 | pr_debug("temperature is: %d F\n" , *temperature); |
577 | } |
578 | |
579 | return 0; |
580 | } |
581 | |
582 | /* |
583 | * /dev/watchdog handling |
584 | */ |
585 | |
586 | static long pcwd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
587 | { |
588 | int rv; |
589 | int status; |
590 | int temperature; |
591 | int new_heartbeat; |
592 | int __user *argp = (int __user *)arg; |
593 | static const struct watchdog_info ident = { |
594 | .options = WDIOF_OVERHEAT | |
595 | WDIOF_CARDRESET | |
596 | WDIOF_KEEPALIVEPING | |
597 | WDIOF_SETTIMEOUT | |
598 | WDIOF_MAGICCLOSE, |
599 | .firmware_version = 1, |
600 | .identity = "PCWD" , |
601 | }; |
602 | |
603 | switch (cmd) { |
604 | case WDIOC_GETSUPPORT: |
605 | if (copy_to_user(to: argp, from: &ident, n: sizeof(ident))) |
606 | return -EFAULT; |
607 | return 0; |
608 | |
609 | case WDIOC_GETSTATUS: |
610 | pcwd_get_status(status: &status); |
611 | return put_user(status, argp); |
612 | |
613 | case WDIOC_GETBOOTSTATUS: |
614 | return put_user(pcwd_private.boot_status, argp); |
615 | |
616 | case WDIOC_GETTEMP: |
617 | if (pcwd_get_temperature(temperature: &temperature)) |
618 | return -EFAULT; |
619 | |
620 | return put_user(temperature, argp); |
621 | |
622 | case WDIOC_SETOPTIONS: |
623 | if (pcwd_private.revision == PCWD_REVISION_C) { |
624 | if (get_user(rv, argp)) |
625 | return -EFAULT; |
626 | |
627 | if (rv & WDIOS_DISABLECARD) { |
628 | status = pcwd_stop(); |
629 | if (status < 0) |
630 | return status; |
631 | } |
632 | if (rv & WDIOS_ENABLECARD) { |
633 | status = pcwd_start(); |
634 | if (status < 0) |
635 | return status; |
636 | } |
637 | if (rv & WDIOS_TEMPPANIC) |
638 | temp_panic = 1; |
639 | } |
640 | return -EINVAL; |
641 | |
642 | case WDIOC_KEEPALIVE: |
643 | pcwd_keepalive(); |
644 | return 0; |
645 | |
646 | case WDIOC_SETTIMEOUT: |
647 | if (get_user(new_heartbeat, argp)) |
648 | return -EFAULT; |
649 | |
650 | if (pcwd_set_heartbeat(t: new_heartbeat)) |
651 | return -EINVAL; |
652 | |
653 | pcwd_keepalive(); |
654 | fallthrough; |
655 | |
656 | case WDIOC_GETTIMEOUT: |
657 | return put_user(heartbeat, argp); |
658 | |
659 | default: |
660 | return -ENOTTY; |
661 | } |
662 | |
663 | return 0; |
664 | } |
665 | |
666 | static ssize_t pcwd_write(struct file *file, const char __user *buf, size_t len, |
667 | loff_t *ppos) |
668 | { |
669 | if (len) { |
670 | if (!nowayout) { |
671 | size_t i; |
672 | |
673 | /* In case it was set long ago */ |
674 | expect_close = 0; |
675 | |
676 | for (i = 0; i != len; i++) { |
677 | char c; |
678 | |
679 | if (get_user(c, buf + i)) |
680 | return -EFAULT; |
681 | if (c == 'V') |
682 | expect_close = 42; |
683 | } |
684 | } |
685 | pcwd_keepalive(); |
686 | } |
687 | return len; |
688 | } |
689 | |
690 | static int pcwd_open(struct inode *inode, struct file *file) |
691 | { |
692 | if (test_and_set_bit(nr: 0, addr: &open_allowed)) |
693 | return -EBUSY; |
694 | if (nowayout) |
695 | __module_get(THIS_MODULE); |
696 | /* Activate */ |
697 | pcwd_start(); |
698 | pcwd_keepalive(); |
699 | return stream_open(inode, filp: file); |
700 | } |
701 | |
702 | static int pcwd_close(struct inode *inode, struct file *file) |
703 | { |
704 | if (expect_close == 42) |
705 | pcwd_stop(); |
706 | else { |
707 | pr_crit("Unexpected close, not stopping watchdog!\n" ); |
708 | pcwd_keepalive(); |
709 | } |
710 | expect_close = 0; |
711 | clear_bit(nr: 0, addr: &open_allowed); |
712 | return 0; |
713 | } |
714 | |
715 | /* |
716 | * /dev/temperature handling |
717 | */ |
718 | |
719 | static ssize_t pcwd_temp_read(struct file *file, char __user *buf, size_t count, |
720 | loff_t *ppos) |
721 | { |
722 | int temperature; |
723 | |
724 | if (pcwd_get_temperature(temperature: &temperature)) |
725 | return -EFAULT; |
726 | |
727 | if (copy_to_user(to: buf, from: &temperature, n: 1)) |
728 | return -EFAULT; |
729 | |
730 | return 1; |
731 | } |
732 | |
733 | static int pcwd_temp_open(struct inode *inode, struct file *file) |
734 | { |
735 | if (!pcwd_private.supports_temp) |
736 | return -ENODEV; |
737 | |
738 | return stream_open(inode, filp: file); |
739 | } |
740 | |
741 | static int pcwd_temp_close(struct inode *inode, struct file *file) |
742 | { |
743 | return 0; |
744 | } |
745 | |
746 | /* |
747 | * Kernel Interfaces |
748 | */ |
749 | |
750 | static const struct file_operations pcwd_fops = { |
751 | .owner = THIS_MODULE, |
752 | .llseek = no_llseek, |
753 | .write = pcwd_write, |
754 | .unlocked_ioctl = pcwd_ioctl, |
755 | .compat_ioctl = compat_ptr_ioctl, |
756 | .open = pcwd_open, |
757 | .release = pcwd_close, |
758 | }; |
759 | |
760 | static struct miscdevice pcwd_miscdev = { |
761 | .minor = WATCHDOG_MINOR, |
762 | .name = "watchdog" , |
763 | .fops = &pcwd_fops, |
764 | }; |
765 | |
766 | static const struct file_operations pcwd_temp_fops = { |
767 | .owner = THIS_MODULE, |
768 | .llseek = no_llseek, |
769 | .read = pcwd_temp_read, |
770 | .open = pcwd_temp_open, |
771 | .release = pcwd_temp_close, |
772 | }; |
773 | |
774 | static struct miscdevice temp_miscdev = { |
775 | .minor = TEMP_MINOR, |
776 | .name = "temperature" , |
777 | .fops = &pcwd_temp_fops, |
778 | }; |
779 | |
780 | /* |
781 | * Init & exit routines |
782 | */ |
783 | |
784 | static inline int get_revision(void) |
785 | { |
786 | int r = PCWD_REVISION_C; |
787 | |
788 | spin_lock(lock: &pcwd_private.io_lock); |
789 | /* REV A cards use only 2 io ports; test |
790 | * presumes a floating bus reads as 0xff. */ |
791 | if ((inb(port: pcwd_private.io_addr + 2) == 0xFF) || |
792 | (inb(port: pcwd_private.io_addr + 3) == 0xFF)) |
793 | r = PCWD_REVISION_A; |
794 | spin_unlock(lock: &pcwd_private.io_lock); |
795 | |
796 | return r; |
797 | } |
798 | |
799 | /* |
800 | * The ISA cards have a heartbeat bit in one of the registers, which |
801 | * register is card dependent. The heartbeat bit is monitored, and if |
802 | * found, is considered proof that a Berkshire card has been found. |
803 | * The initial rate is once per second at board start up, then twice |
804 | * per second for normal operation. |
805 | */ |
806 | static int pcwd_isa_match(struct device *dev, unsigned int id) |
807 | { |
808 | int base_addr = pcwd_ioports[id]; |
809 | int port0, last_port0; /* Reg 0, in case it's REV A */ |
810 | int port1, last_port1; /* Register 1 for REV C cards */ |
811 | int i; |
812 | int retval; |
813 | |
814 | if (debug >= DEBUG) |
815 | pr_debug("pcwd_isa_match id=%d\n" , id); |
816 | |
817 | if (!request_region(base_addr, 4, "PCWD" )) { |
818 | pr_info("Port 0x%04x unavailable\n" , base_addr); |
819 | return 0; |
820 | } |
821 | |
822 | retval = 0; |
823 | |
824 | port0 = inb_p(port: base_addr); /* For REV A boards */ |
825 | port1 = inb_p(port: base_addr + 1); /* For REV C boards */ |
826 | if (port0 != 0xff || port1 != 0xff) { |
827 | /* Not an 'ff' from a floating bus, so must be a card! */ |
828 | for (i = 0; i < 4; ++i) { |
829 | |
830 | msleep(msecs: 500); |
831 | |
832 | last_port0 = port0; |
833 | last_port1 = port1; |
834 | |
835 | port0 = inb_p(port: base_addr); |
836 | port1 = inb_p(port: base_addr + 1); |
837 | |
838 | /* Has either hearbeat bit changed? */ |
839 | if ((port0 ^ last_port0) & WD_HRTBT || |
840 | (port1 ^ last_port1) & WD_REVC_HRBT) { |
841 | retval = 1; |
842 | break; |
843 | } |
844 | } |
845 | } |
846 | release_region(base_addr, 4); |
847 | |
848 | return retval; |
849 | } |
850 | |
851 | static int pcwd_isa_probe(struct device *dev, unsigned int id) |
852 | { |
853 | int ret; |
854 | |
855 | if (debug >= DEBUG) |
856 | pr_debug("pcwd_isa_probe id=%d\n" , id); |
857 | |
858 | cards_found++; |
859 | if (cards_found == 1) |
860 | pr_info("v%s Ken Hollis (kenji@bitgate.com)\n" , |
861 | WATCHDOG_VERSION); |
862 | |
863 | if (cards_found > 1) { |
864 | pr_err("This driver only supports 1 device\n" ); |
865 | return -ENODEV; |
866 | } |
867 | |
868 | if (pcwd_ioports[id] == 0x0000) { |
869 | pr_err("No I/O-Address for card detected\n" ); |
870 | return -ENODEV; |
871 | } |
872 | pcwd_private.io_addr = pcwd_ioports[id]; |
873 | |
874 | spin_lock_init(&pcwd_private.io_lock); |
875 | |
876 | /* Check card's revision */ |
877 | pcwd_private.revision = get_revision(); |
878 | |
879 | if (!request_region(pcwd_private.io_addr, |
880 | (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4, "PCWD" )) { |
881 | pr_err("I/O address 0x%04x already in use\n" , |
882 | pcwd_private.io_addr); |
883 | ret = -EIO; |
884 | goto error_request_region; |
885 | } |
886 | |
887 | /* Initial variables */ |
888 | pcwd_private.supports_temp = 0; |
889 | temp_panic = 0; |
890 | pcwd_private.boot_status = 0x0000; |
891 | |
892 | /* get the boot_status */ |
893 | pcwd_get_status(status: &pcwd_private.boot_status); |
894 | |
895 | /* clear the "card caused reboot" flag */ |
896 | pcwd_clear_status(); |
897 | |
898 | timer_setup(&pcwd_private.timer, pcwd_timer_ping, 0); |
899 | |
900 | /* Disable the board */ |
901 | pcwd_stop(); |
902 | |
903 | /* Check whether or not the card supports the temperature device */ |
904 | pcwd_check_temperature_support(); |
905 | |
906 | /* Show info about the card itself */ |
907 | pcwd_show_card_info(); |
908 | |
909 | /* If heartbeat = 0 then we use the heartbeat from the dip-switches */ |
910 | if (heartbeat == 0) |
911 | heartbeat = heartbeat_tbl[(pcwd_get_option_switches() & 0x07)]; |
912 | |
913 | /* Check that the heartbeat value is within it's range; |
914 | if not reset to the default */ |
915 | if (pcwd_set_heartbeat(t: heartbeat)) { |
916 | pcwd_set_heartbeat(WATCHDOG_HEARTBEAT); |
917 | pr_info("heartbeat value must be 2 <= heartbeat <= 7200, using %d\n" , |
918 | WATCHDOG_HEARTBEAT); |
919 | } |
920 | |
921 | if (pcwd_private.supports_temp) { |
922 | ret = misc_register(misc: &temp_miscdev); |
923 | if (ret) { |
924 | pr_err("cannot register miscdev on minor=%d (err=%d)\n" , |
925 | TEMP_MINOR, ret); |
926 | goto error_misc_register_temp; |
927 | } |
928 | } |
929 | |
930 | ret = misc_register(misc: &pcwd_miscdev); |
931 | if (ret) { |
932 | pr_err("cannot register miscdev on minor=%d (err=%d)\n" , |
933 | WATCHDOG_MINOR, ret); |
934 | goto error_misc_register_watchdog; |
935 | } |
936 | |
937 | pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n" , |
938 | heartbeat, nowayout); |
939 | |
940 | return 0; |
941 | |
942 | error_misc_register_watchdog: |
943 | if (pcwd_private.supports_temp) |
944 | misc_deregister(misc: &temp_miscdev); |
945 | error_misc_register_temp: |
946 | release_region(pcwd_private.io_addr, |
947 | (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4); |
948 | error_request_region: |
949 | pcwd_private.io_addr = 0x0000; |
950 | cards_found--; |
951 | return ret; |
952 | } |
953 | |
954 | static void pcwd_isa_remove(struct device *dev, unsigned int id) |
955 | { |
956 | if (debug >= DEBUG) |
957 | pr_debug("pcwd_isa_remove id=%d\n" , id); |
958 | |
959 | /* Disable the board */ |
960 | if (!nowayout) |
961 | pcwd_stop(); |
962 | |
963 | /* Deregister */ |
964 | misc_deregister(misc: &pcwd_miscdev); |
965 | if (pcwd_private.supports_temp) |
966 | misc_deregister(misc: &temp_miscdev); |
967 | release_region(pcwd_private.io_addr, |
968 | (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4); |
969 | pcwd_private.io_addr = 0x0000; |
970 | cards_found--; |
971 | } |
972 | |
973 | static void pcwd_isa_shutdown(struct device *dev, unsigned int id) |
974 | { |
975 | if (debug >= DEBUG) |
976 | pr_debug("pcwd_isa_shutdown id=%d\n" , id); |
977 | |
978 | pcwd_stop(); |
979 | } |
980 | |
981 | static struct isa_driver pcwd_isa_driver = { |
982 | .match = pcwd_isa_match, |
983 | .probe = pcwd_isa_probe, |
984 | .remove = pcwd_isa_remove, |
985 | .shutdown = pcwd_isa_shutdown, |
986 | .driver = { |
987 | .owner = THIS_MODULE, |
988 | .name = WATCHDOG_NAME, |
989 | }, |
990 | }; |
991 | |
992 | module_isa_driver(pcwd_isa_driver, PCWD_ISA_NR_CARDS); |
993 | |
994 | MODULE_AUTHOR("Ken Hollis <kenji@bitgate.com>, " |
995 | "Wim Van Sebroeck <wim@iguana.be>" ); |
996 | MODULE_DESCRIPTION("Berkshire ISA-PC Watchdog driver" ); |
997 | MODULE_VERSION(WATCHDOG_VERSION); |
998 | MODULE_LICENSE("GPL" ); |
999 | |