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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * dell-smm-hwmon.c -- Linux driver for accessing the SMM BIOS on Dell laptops.
4 *
5 * Copyright (C) 2001 Massimo Dal Zotto <dz@debian.org>
6 *
7 * Hwmon integration:
8 * Copyright (C) 2011 Jean Delvare <jdelvare@suse.de>
9 * Copyright (C) 2013, 2014 Guenter Roeck <linux@roeck-us.net>
10 * Copyright (C) 2014, 2015 Pali Rohár <pali@kernel.org>
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/cpu.h>
16#include <linux/delay.h>
17#include <linux/module.h>
18#include <linux/types.h>
19#include <linux/init.h>
20#include <linux/proc_fs.h>
21#include <linux/seq_file.h>
22#include <linux/dmi.h>
23#include <linux/capability.h>
24#include <linux/mutex.h>
25#include <linux/hwmon.h>
26#include <linux/hwmon-sysfs.h>
27#include <linux/uaccess.h>
28#include <linux/io.h>
29#include <linux/sched.h>
30#include <linux/ctype.h>
31#include <linux/smp.h>
32
33#include <linux/i8k.h>
34
35#define I8K_SMM_FN_STATUS 0x0025
36#define I8K_SMM_POWER_STATUS 0x0069
37#define I8K_SMM_SET_FAN 0x01a3
38#define I8K_SMM_GET_FAN 0x00a3
39#define I8K_SMM_GET_SPEED 0x02a3
40#define I8K_SMM_GET_FAN_TYPE 0x03a3
41#define I8K_SMM_GET_NOM_SPEED 0x04a3
42#define I8K_SMM_GET_TEMP 0x10a3
43#define I8K_SMM_GET_TEMP_TYPE 0x11a3
44#define I8K_SMM_GET_DELL_SIG1 0xfea3
45#define I8K_SMM_GET_DELL_SIG2 0xffa3
46
47#define I8K_FAN_MULT 30
48#define I8K_FAN_MAX_RPM 30000
49#define I8K_MAX_TEMP 127
50
51#define I8K_FN_NONE 0x00
52#define I8K_FN_UP 0x01
53#define I8K_FN_DOWN 0x02
54#define I8K_FN_MUTE 0x04
55#define I8K_FN_MASK 0x07
56#define I8K_FN_SHIFT 8
57
58#define I8K_POWER_AC 0x05
59#define I8K_POWER_BATTERY 0x01
60
61static DEFINE_MUTEX(i8k_mutex);
62static char bios_version[4];
63static char bios_machineid[16];
64static struct device *i8k_hwmon_dev;
65static u32 i8k_hwmon_flags;
66static uint i8k_fan_mult = I8K_FAN_MULT;
67static uint i8k_pwm_mult;
68static uint i8k_fan_max = I8K_FAN_HIGH;
69static bool disallow_fan_type_call;
70static bool disallow_fan_support;
71static unsigned int manual_fan;
72static unsigned int auto_fan;
73
74#define I8K_HWMON_HAVE_TEMP1 (1 << 0)
75#define I8K_HWMON_HAVE_TEMP2 (1 << 1)
76#define I8K_HWMON_HAVE_TEMP3 (1 << 2)
77#define I8K_HWMON_HAVE_TEMP4 (1 << 3)
78#define I8K_HWMON_HAVE_TEMP5 (1 << 4)
79#define I8K_HWMON_HAVE_TEMP6 (1 << 5)
80#define I8K_HWMON_HAVE_TEMP7 (1 << 6)
81#define I8K_HWMON_HAVE_TEMP8 (1 << 7)
82#define I8K_HWMON_HAVE_TEMP9 (1 << 8)
83#define I8K_HWMON_HAVE_TEMP10 (1 << 9)
84#define I8K_HWMON_HAVE_FAN1 (1 << 10)
85#define I8K_HWMON_HAVE_FAN2 (1 << 11)
86#define I8K_HWMON_HAVE_FAN3 (1 << 12)
87
88MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
89MODULE_AUTHOR("Pali Rohár <pali@kernel.org>");
90MODULE_DESCRIPTION("Dell laptop SMM BIOS hwmon driver");
91MODULE_LICENSE("GPL");
92MODULE_ALIAS("i8k");
93
94static bool force;
95module_param(force, bool, 0);
96MODULE_PARM_DESC(force, "Force loading without checking for supported models");
97
98static bool ignore_dmi;
99module_param(ignore_dmi, bool, 0);
100MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
101
102#if IS_ENABLED(CONFIG_I8K)
103static bool restricted = true;
104module_param(restricted, bool, 0);
105MODULE_PARM_DESC(restricted, "Restrict fan control and serial number to CAP_SYS_ADMIN (default: 1)");
106
107static bool power_status;
108module_param(power_status, bool, 0600);
109MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k (default: 0)");
110#endif
111
112static uint fan_mult;
113module_param(fan_mult, uint, 0);
114MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with (default: autodetect)");
115
116static uint fan_max;
117module_param(fan_max, uint, 0);
118MODULE_PARM_DESC(fan_max, "Maximum configurable fan speed (default: autodetect)");
119
120struct smm_regs {
121 unsigned int eax;
122 unsigned int ebx __packed;
123 unsigned int ecx __packed;
124 unsigned int edx __packed;
125 unsigned int esi __packed;
126 unsigned int edi __packed;
127};
128
129static inline const char *i8k_get_dmi_data(int field)
130{
131 const char *dmi_data = dmi_get_system_info(field);
132
133 return dmi_data && *dmi_data ? dmi_data : "?";
134}
135
136/*
137 * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard.
138 */
139static int i8k_smm_func(void *par)
140{
141 int rc;
142 struct smm_regs *regs = par;
143 int eax = regs->eax;
144
145#ifdef DEBUG
146 int ebx = regs->ebx;
147 unsigned long duration;
148 ktime_t calltime, delta, rettime;
149
150 calltime = ktime_get();
151#endif
152
153 /* SMM requires CPU 0 */
154 if (smp_processor_id() != 0)
155 return -EBUSY;
156
157#if defined(CONFIG_X86_64)
158 asm volatile("pushq %%rax\n\t"
159 "movl 0(%%rax),%%edx\n\t"
160 "pushq %%rdx\n\t"
161 "movl 4(%%rax),%%ebx\n\t"
162 "movl 8(%%rax),%%ecx\n\t"
163 "movl 12(%%rax),%%edx\n\t"
164 "movl 16(%%rax),%%esi\n\t"
165 "movl 20(%%rax),%%edi\n\t"
166 "popq %%rax\n\t"
167 "out %%al,$0xb2\n\t"
168 "out %%al,$0x84\n\t"
169 "xchgq %%rax,(%%rsp)\n\t"
170 "movl %%ebx,4(%%rax)\n\t"
171 "movl %%ecx,8(%%rax)\n\t"
172 "movl %%edx,12(%%rax)\n\t"
173 "movl %%esi,16(%%rax)\n\t"
174 "movl %%edi,20(%%rax)\n\t"
175 "popq %%rdx\n\t"
176 "movl %%edx,0(%%rax)\n\t"
177 "pushfq\n\t"
178 "popq %%rax\n\t"
179 "andl $1,%%eax\n"
180 : "=a"(rc)
181 : "a"(regs)
182 : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
183#else
184 asm volatile("pushl %%eax\n\t"
185 "movl 0(%%eax),%%edx\n\t"
186 "push %%edx\n\t"
187 "movl 4(%%eax),%%ebx\n\t"
188 "movl 8(%%eax),%%ecx\n\t"
189 "movl 12(%%eax),%%edx\n\t"
190 "movl 16(%%eax),%%esi\n\t"
191 "movl 20(%%eax),%%edi\n\t"
192 "popl %%eax\n\t"
193 "out %%al,$0xb2\n\t"
194 "out %%al,$0x84\n\t"
195 "xchgl %%eax,(%%esp)\n\t"
196 "movl %%ebx,4(%%eax)\n\t"
197 "movl %%ecx,8(%%eax)\n\t"
198 "movl %%edx,12(%%eax)\n\t"
199 "movl %%esi,16(%%eax)\n\t"
200 "movl %%edi,20(%%eax)\n\t"
201 "popl %%edx\n\t"
202 "movl %%edx,0(%%eax)\n\t"
203 "lahf\n\t"
204 "shrl $8,%%eax\n\t"
205 "andl $1,%%eax\n"
206 : "=a"(rc)
207 : "a"(regs)
208 : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
209#endif
210 if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
211 rc = -EINVAL;
212
213#ifdef DEBUG
214 rettime = ktime_get();
215 delta = ktime_sub(rettime, calltime);
216 duration = ktime_to_ns(delta) >> 10;
217 pr_debug("smm(0x%.4x 0x%.4x) = 0x%.4x (took %7lu usecs)\n", eax, ebx,
218 (rc ? 0xffff : regs->eax & 0xffff), duration);
219#endif
220
221 return rc;
222}
223
224/*
225 * Call the System Management Mode BIOS.
226 */
227static int i8k_smm(struct smm_regs *regs)
228{
229 int ret;
230
231 get_online_cpus();
232 ret = smp_call_on_cpu(0, i8k_smm_func, regs, true);
233 put_online_cpus();
234
235 return ret;
236}
237
238/*
239 * Read the fan status.
240 */
241static int i8k_get_fan_status(int fan)
242{
243 struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, };
244
245 if (disallow_fan_support)
246 return -EINVAL;
247
248 regs.ebx = fan & 0xff;
249 return i8k_smm(®s) ? : regs.eax & 0xff;
250}
251
252/*
253 * Read the fan speed in RPM.
254 */
255static int i8k_get_fan_speed(int fan)
256{
257 struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, };
258
259 if (disallow_fan_support)
260 return -EINVAL;
261
262 regs.ebx = fan & 0xff;
263 return i8k_smm(®s) ? : (regs.eax & 0xffff) * i8k_fan_mult;
264}
265
266/*
267 * Read the fan type.
268 */
269static int _i8k_get_fan_type(int fan)
270{
271 struct smm_regs regs = { .eax = I8K_SMM_GET_FAN_TYPE, };
272
273 if (disallow_fan_support || disallow_fan_type_call)
274 return -EINVAL;
275
276 regs.ebx = fan & 0xff;
277 return i8k_smm(®s) ? : regs.eax & 0xff;
278}
279
280static int i8k_get_fan_type(int fan)
281{
282 /* I8K_SMM_GET_FAN_TYPE SMM call is expensive, so cache values */
283 static int types[3] = { INT_MIN, INT_MIN, INT_MIN };
284
285 if (types[fan] == INT_MIN)
286 types[fan] = _i8k_get_fan_type(fan);
287
288 return types[fan];
289}
290
291/*
292 * Read the fan nominal rpm for specific fan speed.
293 */
294static int i8k_get_fan_nominal_speed(int fan, int speed)
295{
296 struct smm_regs regs = { .eax = I8K_SMM_GET_NOM_SPEED, };
297
298 if (disallow_fan_support)
299 return -EINVAL;
300
301 regs.ebx = (fan & 0xff) | (speed << 8);
302 return i8k_smm(®s) ? : (regs.eax & 0xffff) * i8k_fan_mult;
303}
304
305/*
306 * Enable or disable automatic BIOS fan control support
307 */
308static int i8k_enable_fan_auto_mode(bool enable)
309{
310 struct smm_regs regs = { };
311
312 if (disallow_fan_support)
313 return -EINVAL;
314
315 regs.eax = enable ? auto_fan : manual_fan;
316 return i8k_smm(®s);
317}
318
319/*
320 * Set the fan speed (off, low, high). Returns the new fan status.
321 */
322static int i8k_set_fan(int fan, int speed)
323{
324 struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
325
326 if (disallow_fan_support)
327 return -EINVAL;
328
329 speed = (speed < 0) ? 0 : ((speed > i8k_fan_max) ? i8k_fan_max : speed);
330 regs.ebx = (fan & 0xff) | (speed << 8);
331
332 return i8k_smm(®s) ? : i8k_get_fan_status(fan);
333}
334
335static int i8k_get_temp_type(int sensor)
336{
337 struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP_TYPE, };
338
339 regs.ebx = sensor & 0xff;
340 return i8k_smm(®s) ? : regs.eax & 0xff;
341}
342
343/*
344 * Read the cpu temperature.
345 */
346static int _i8k_get_temp(int sensor)
347{
348 struct smm_regs regs = {
349 .eax = I8K_SMM_GET_TEMP,
350 .ebx = sensor & 0xff,
351 };
352
353 return i8k_smm(®s) ? : regs.eax & 0xff;
354}
355
356static int i8k_get_temp(int sensor)
357{
358 int temp = _i8k_get_temp(sensor);
359
360 /*
361 * Sometimes the temperature sensor returns 0x99, which is out of range.
362 * In this case we retry (once) before returning an error.
363 # 1003655137 00000058 00005a4b
364 # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
365 # 1003655139 00000054 00005c52
366 */
367 if (temp == 0x99) {
368 msleep(100);
369 temp = _i8k_get_temp(sensor);
370 }
371 /*
372 * Return -ENODATA for all invalid temperatures.
373 *
374 * Known instances are the 0x99 value as seen above as well as
375 * 0xc1 (193), which may be returned when trying to read the GPU
376 * temperature if the system supports a GPU and it is currently
377 * turned off.
378 */
379 if (temp > I8K_MAX_TEMP)
380 return -ENODATA;
381
382 return temp;
383}
384
385static int i8k_get_dell_signature(int req_fn)
386{
387 struct smm_regs regs = { .eax = req_fn, };
388 int rc;
389
390 rc = i8k_smm(®s);
391 if (rc < 0)
392 return rc;
393
394 return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
395}
396
397#if IS_ENABLED(CONFIG_I8K)
398
399/*
400 * Read the Fn key status.
401 */
402static int i8k_get_fn_status(void)
403{
404 struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, };
405 int rc;
406
407 rc = i8k_smm(®s);
408 if (rc < 0)
409 return rc;
410
411 switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) {
412 case I8K_FN_UP:
413 return I8K_VOL_UP;
414 case I8K_FN_DOWN:
415 return I8K_VOL_DOWN;
416 case I8K_FN_MUTE:
417 return I8K_VOL_MUTE;
418 default:
419 return 0;
420 }
421}
422
423/*
424 * Read the power status.
425 */
426static int i8k_get_power_status(void)
427{
428 struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, };
429 int rc;
430
431 rc = i8k_smm(®s);
432 if (rc < 0)
433 return rc;
434
435 return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY;
436}
437
438/*
439 * Procfs interface
440 */
441
442static int
443i8k_ioctl_unlocked(struct file *fp, unsigned int cmd, unsigned long arg)
444{
445 int val = 0;
446 int speed;
447 unsigned char buff[16];
448 int __user *argp = (int __user *)arg;
449
450 if (!argp)
451 return -EINVAL;
452
453 switch (cmd) {
454 case I8K_BIOS_VERSION:
455 if (!isdigit(bios_version[0]) || !isdigit(bios_version[1]) ||
456 !isdigit(bios_version[2]))
457 return -EINVAL;
458
459 val = (bios_version[0] << 16) |
460 (bios_version[1] << 8) | bios_version[2];
461 break;
462
463 case I8K_MACHINE_ID:
464 if (restricted && !capable(CAP_SYS_ADMIN))
465 return -EPERM;
466
467 memset(buff, 0, sizeof(buff));
468 strlcpy(buff, bios_machineid, sizeof(buff));
469 break;
470
471 case I8K_FN_STATUS:
472 val = i8k_get_fn_status();
473 break;
474
475 case I8K_POWER_STATUS:
476 val = i8k_get_power_status();
477 break;
478
479 case I8K_GET_TEMP:
480 val = i8k_get_temp(0);
481 break;
482
483 case I8K_GET_SPEED:
484 if (copy_from_user(&val, argp, sizeof(int)))
485 return -EFAULT;
486
487 val = i8k_get_fan_speed(val);
488 break;
489
490 case I8K_GET_FAN:
491 if (copy_from_user(&val, argp, sizeof(int)))
492 return -EFAULT;
493
494 val = i8k_get_fan_status(val);
495 break;
496
497 case I8K_SET_FAN:
498 if (restricted && !capable(CAP_SYS_ADMIN))
499 return -EPERM;
500
501 if (copy_from_user(&val, argp, sizeof(int)))
502 return -EFAULT;
503
504 if (copy_from_user(&speed, argp + 1, sizeof(int)))
505 return -EFAULT;
506
507 val = i8k_set_fan(val, speed);
508 break;
509
510 default:
511 return -EINVAL;
512 }
513
514 if (val < 0)
515 return val;
516
517 switch (cmd) {
518 case I8K_BIOS_VERSION:
519 if (copy_to_user(argp, &val, 4))
520 return -EFAULT;
521
522 break;
523 case I8K_MACHINE_ID:
524 if (copy_to_user(argp, buff, 16))
525 return -EFAULT;
526
527 break;
528 default:
529 if (copy_to_user(argp, &val, sizeof(int)))
530 return -EFAULT;
531
532 break;
533 }
534
535 return 0;
536}
537
538static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
539{
540 long ret;
541
542 mutex_lock(&i8k_mutex);
543 ret = i8k_ioctl_unlocked(fp, cmd, arg);
544 mutex_unlock(&i8k_mutex);
545
546 return ret;
547}
548
549/*
550 * Print the information for /proc/i8k.
551 */
552static int i8k_proc_show(struct seq_file *seq, void *offset)
553{
554 int fn_key, cpu_temp, ac_power;
555 int left_fan, right_fan, left_speed, right_speed;
556
557 cpu_temp = i8k_get_temp(0); /* 11100 µs */
558 left_fan = i8k_get_fan_status(I8K_FAN_LEFT); /* 580 µs */
559 right_fan = i8k_get_fan_status(I8K_FAN_RIGHT); /* 580 µs */
560 left_speed = i8k_get_fan_speed(I8K_FAN_LEFT); /* 580 µs */
561 right_speed = i8k_get_fan_speed(I8K_FAN_RIGHT); /* 580 µs */
562 fn_key = i8k_get_fn_status(); /* 750 µs */
563 if (power_status)
564 ac_power = i8k_get_power_status(); /* 14700 µs */
565 else
566 ac_power = -1;
567
568 /*
569 * Info:
570 *
571 * 1) Format version (this will change if format changes)
572 * 2) BIOS version
573 * 3) BIOS machine ID
574 * 4) Cpu temperature
575 * 5) Left fan status
576 * 6) Right fan status
577 * 7) Left fan speed
578 * 8) Right fan speed
579 * 9) AC power
580 * 10) Fn Key status
581 */
582 seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
583 I8K_PROC_FMT,
584 bios_version,
585 (restricted && !capable(CAP_SYS_ADMIN)) ? "-1" : bios_machineid,
586 cpu_temp,
587 left_fan, right_fan, left_speed, right_speed,
588 ac_power, fn_key);
589
590 return 0;
591}
592
593static int i8k_open_fs(struct inode *inode, struct file *file)
594{
595 return single_open(file, i8k_proc_show, NULL);
596}
597
598static const struct proc_ops i8k_proc_ops = {
599 .proc_open = i8k_open_fs,
600 .proc_read = seq_read,
601 .proc_lseek = seq_lseek,
602 .proc_release = single_release,
603 .proc_ioctl = i8k_ioctl,
604};
605
606static void __init i8k_init_procfs(void)
607{
608 /* Register the proc entry */
609 proc_create("i8k", 0, NULL, &i8k_proc_ops);
610}
611
612static void __exit i8k_exit_procfs(void)
613{
614 remove_proc_entry("i8k", NULL);
615}
616
617#else
618
619static inline void __init i8k_init_procfs(void)
620{
621}
622
623static inline void __exit i8k_exit_procfs(void)
624{
625}
626
627#endif
628
629/*
630 * Hwmon interface
631 */
632
633static ssize_t i8k_hwmon_temp_label_show(struct device *dev,
634 struct device_attribute *devattr,
635 char *buf)
636{
637 static const char * const labels[] = {
638 "CPU",
639 "GPU",
640 "SODIMM",
641 "Other",
642 "Ambient",
643 "Other",
644 };
645 int index = to_sensor_dev_attr(devattr)->index;
646 int type;
647
648 type = i8k_get_temp_type(index);
649 if (type < 0)
650 return type;
651 if (type >= ARRAY_SIZE(labels))
652 type = ARRAY_SIZE(labels) - 1;
653 return sprintf(buf, "%s\n", labels[type]);
654}
655
656static ssize_t i8k_hwmon_temp_show(struct device *dev,
657 struct device_attribute *devattr,
658 char *buf)
659{
660 int index = to_sensor_dev_attr(devattr)->index;
661 int temp;
662
663 temp = i8k_get_temp(index);
664 if (temp < 0)
665 return temp;
666 return sprintf(buf, "%d\n", temp * 1000);
667}
668
669static ssize_t i8k_hwmon_fan_label_show(struct device *dev,
670 struct device_attribute *devattr,
671 char *buf)
672{
673 static const char * const labels[] = {
674 "Processor Fan",
675 "Motherboard Fan",
676 "Video Fan",
677 "Power Supply Fan",
678 "Chipset Fan",
679 "Other Fan",
680 };
681 int index = to_sensor_dev_attr(devattr)->index;
682 bool dock = false;
683 int type;
684
685 type = i8k_get_fan_type(index);
686 if (type < 0)
687 return type;
688
689 if (type & 0x10) {
690 dock = true;
691 type &= 0x0F;
692 }
693
694 if (type >= ARRAY_SIZE(labels))
695 type = (ARRAY_SIZE(labels) - 1);
696
697 return sprintf(buf, "%s%s\n", (dock ? "Docking " : ""), labels[type]);
698}
699
700static ssize_t i8k_hwmon_fan_show(struct device *dev,
701 struct device_attribute *devattr, char *buf)
702{
703 int index = to_sensor_dev_attr(devattr)->index;
704 int fan_speed;
705
706 fan_speed = i8k_get_fan_speed(index);
707 if (fan_speed < 0)
708 return fan_speed;
709 return sprintf(buf, "%d\n", fan_speed);
710}
711
712static ssize_t i8k_hwmon_pwm_show(struct device *dev,
713 struct device_attribute *devattr, char *buf)
714{
715 int index = to_sensor_dev_attr(devattr)->index;
716 int status;
717
718 status = i8k_get_fan_status(index);
719 if (status < 0)
720 return -EIO;
721 return sprintf(buf, "%d\n", clamp_val(status * i8k_pwm_mult, 0, 255));
722}
723
724static ssize_t i8k_hwmon_pwm_store(struct device *dev,
725 struct device_attribute *attr,
726 const char *buf, size_t count)
727{
728 int index = to_sensor_dev_attr(attr)->index;
729 unsigned long val;
730 int err;
731
732 err = kstrtoul(buf, 10, &val);
733 if (err)
734 return err;
735 val = clamp_val(DIV_ROUND_CLOSEST(val, i8k_pwm_mult), 0, i8k_fan_max);
736
737 mutex_lock(&i8k_mutex);
738 err = i8k_set_fan(index, val);
739 mutex_unlock(&i8k_mutex);
740
741 return err < 0 ? -EIO : count;
742}
743
744static ssize_t i8k_hwmon_pwm_enable_store(struct device *dev,
745 struct device_attribute *attr,
746 const char *buf, size_t count)
747{
748 int err;
749 bool enable;
750 unsigned long val;
751
752 if (!auto_fan)
753 return -ENODEV;
754
755 err = kstrtoul(buf, 10, &val);
756 if (err)
757 return err;
758
759 if (val == 1)
760 enable = false;
761 else if (val == 2)
762 enable = true;
763 else
764 return -EINVAL;
765
766 mutex_lock(&i8k_mutex);
767 err = i8k_enable_fan_auto_mode(enable);
768 mutex_unlock(&i8k_mutex);
769
770 return err ? err : count;
771}
772
773static SENSOR_DEVICE_ATTR_RO(temp1_input, i8k_hwmon_temp, 0);
774static SENSOR_DEVICE_ATTR_RO(temp1_label, i8k_hwmon_temp_label, 0);
775static SENSOR_DEVICE_ATTR_RO(temp2_input, i8k_hwmon_temp, 1);
776static SENSOR_DEVICE_ATTR_RO(temp2_label, i8k_hwmon_temp_label, 1);
777static SENSOR_DEVICE_ATTR_RO(temp3_input, i8k_hwmon_temp, 2);
778static SENSOR_DEVICE_ATTR_RO(temp3_label, i8k_hwmon_temp_label, 2);
779static SENSOR_DEVICE_ATTR_RO(temp4_input, i8k_hwmon_temp, 3);
780static SENSOR_DEVICE_ATTR_RO(temp4_label, i8k_hwmon_temp_label, 3);
781static SENSOR_DEVICE_ATTR_RO(temp5_input, i8k_hwmon_temp, 4);
782static SENSOR_DEVICE_ATTR_RO(temp5_label, i8k_hwmon_temp_label, 4);
783static SENSOR_DEVICE_ATTR_RO(temp6_input, i8k_hwmon_temp, 5);
784static SENSOR_DEVICE_ATTR_RO(temp6_label, i8k_hwmon_temp_label, 5);
785static SENSOR_DEVICE_ATTR_RO(temp7_input, i8k_hwmon_temp, 6);
786static SENSOR_DEVICE_ATTR_RO(temp7_label, i8k_hwmon_temp_label, 6);
787static SENSOR_DEVICE_ATTR_RO(temp8_input, i8k_hwmon_temp, 7);
788static SENSOR_DEVICE_ATTR_RO(temp8_label, i8k_hwmon_temp_label, 7);
789static SENSOR_DEVICE_ATTR_RO(temp9_input, i8k_hwmon_temp, 8);
790static SENSOR_DEVICE_ATTR_RO(temp9_label, i8k_hwmon_temp_label, 8);
791static SENSOR_DEVICE_ATTR_RO(temp10_input, i8k_hwmon_temp, 9);
792static SENSOR_DEVICE_ATTR_RO(temp10_label, i8k_hwmon_temp_label, 9);
793static SENSOR_DEVICE_ATTR_RO(fan1_input, i8k_hwmon_fan, 0);
794static SENSOR_DEVICE_ATTR_RO(fan1_label, i8k_hwmon_fan_label, 0);
795static SENSOR_DEVICE_ATTR_RW(pwm1, i8k_hwmon_pwm, 0);
796static SENSOR_DEVICE_ATTR_WO(pwm1_enable, i8k_hwmon_pwm_enable, 0);
797static SENSOR_DEVICE_ATTR_RO(fan2_input, i8k_hwmon_fan, 1);
798static SENSOR_DEVICE_ATTR_RO(fan2_label, i8k_hwmon_fan_label, 1);
799static SENSOR_DEVICE_ATTR_RW(pwm2, i8k_hwmon_pwm, 1);
800static SENSOR_DEVICE_ATTR_RO(fan3_input, i8k_hwmon_fan, 2);
801static SENSOR_DEVICE_ATTR_RO(fan3_label, i8k_hwmon_fan_label, 2);
802static SENSOR_DEVICE_ATTR_RW(pwm3, i8k_hwmon_pwm, 2);
803
804static struct attribute *i8k_attrs[] = {
805 &sensor_dev_attr_temp1_input.dev_attr.attr, /* 0 */
806 &sensor_dev_attr_temp1_label.dev_attr.attr, /* 1 */
807 &sensor_dev_attr_temp2_input.dev_attr.attr, /* 2 */
808 &sensor_dev_attr_temp2_label.dev_attr.attr, /* 3 */
809 &sensor_dev_attr_temp3_input.dev_attr.attr, /* 4 */
810 &sensor_dev_attr_temp3_label.dev_attr.attr, /* 5 */
811 &sensor_dev_attr_temp4_input.dev_attr.attr, /* 6 */
812 &sensor_dev_attr_temp4_label.dev_attr.attr, /* 7 */
813 &sensor_dev_attr_temp5_input.dev_attr.attr, /* 8 */
814 &sensor_dev_attr_temp5_label.dev_attr.attr, /* 9 */
815 &sensor_dev_attr_temp6_input.dev_attr.attr, /* 10 */
816 &sensor_dev_attr_temp6_label.dev_attr.attr, /* 11 */
817 &sensor_dev_attr_temp7_input.dev_attr.attr, /* 12 */
818 &sensor_dev_attr_temp7_label.dev_attr.attr, /* 13 */
819 &sensor_dev_attr_temp8_input.dev_attr.attr, /* 14 */
820 &sensor_dev_attr_temp8_label.dev_attr.attr, /* 15 */
821 &sensor_dev_attr_temp9_input.dev_attr.attr, /* 16 */
822 &sensor_dev_attr_temp9_label.dev_attr.attr, /* 17 */
823 &sensor_dev_attr_temp10_input.dev_attr.attr, /* 18 */
824 &sensor_dev_attr_temp10_label.dev_attr.attr, /* 19 */
825 &sensor_dev_attr_fan1_input.dev_attr.attr, /* 20 */
826 &sensor_dev_attr_fan1_label.dev_attr.attr, /* 21 */
827 &sensor_dev_attr_pwm1.dev_attr.attr, /* 22 */
828 &sensor_dev_attr_pwm1_enable.dev_attr.attr, /* 23 */
829 &sensor_dev_attr_fan2_input.dev_attr.attr, /* 24 */
830 &sensor_dev_attr_fan2_label.dev_attr.attr, /* 25 */
831 &sensor_dev_attr_pwm2.dev_attr.attr, /* 26 */
832 &sensor_dev_attr_fan3_input.dev_attr.attr, /* 27 */
833 &sensor_dev_attr_fan3_label.dev_attr.attr, /* 28 */
834 &sensor_dev_attr_pwm3.dev_attr.attr, /* 29 */
835 NULL
836};
837
838static umode_t i8k_is_visible(struct kobject *kobj, struct attribute *attr,
839 int index)
840{
841 if (disallow_fan_support && index >= 20)
842 return 0;
843 if (disallow_fan_type_call &&
844 (index == 21 || index == 25 || index == 28))
845 return 0;
846 if (index >= 0 && index <= 1 &&
847 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP1))
848 return 0;
849 if (index >= 2 && index <= 3 &&
850 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP2))
851 return 0;
852 if (index >= 4 && index <= 5 &&
853 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP3))
854 return 0;
855 if (index >= 6 && index <= 7 &&
856 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP4))
857 return 0;
858 if (index >= 8 && index <= 9 &&
859 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP5))
860 return 0;
861 if (index >= 10 && index <= 11 &&
862 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP6))
863 return 0;
864 if (index >= 12 && index <= 13 &&
865 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP7))
866 return 0;
867 if (index >= 14 && index <= 15 &&
868 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP8))
869 return 0;
870 if (index >= 16 && index <= 17 &&
871 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP9))
872 return 0;
873 if (index >= 18 && index <= 19 &&
874 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP10))
875 return 0;
876
877 if (index >= 20 && index <= 23 &&
878 !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN1))
879 return 0;
880 if (index >= 24 && index <= 26 &&
881 !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN2))
882 return 0;
883 if (index >= 27 && index <= 29 &&
884 !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN3))
885 return 0;
886
887 if (index == 23 && !auto_fan)
888 return 0;
889
890 return attr->mode;
891}
892
893static const struct attribute_group i8k_group = {
894 .attrs = i8k_attrs,
895 .is_visible = i8k_is_visible,
896};
897__ATTRIBUTE_GROUPS(i8k);
898
899static int __init i8k_init_hwmon(void)
900{
901 int err;
902
903 i8k_hwmon_flags = 0;
904
905 /* CPU temperature attributes, if temperature type is OK */
906 err = i8k_get_temp_type(0);
907 if (err >= 0)
908 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP1;
909 /* check for additional temperature sensors */
910 err = i8k_get_temp_type(1);
911 if (err >= 0)
912 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP2;
913 err = i8k_get_temp_type(2);
914 if (err >= 0)
915 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP3;
916 err = i8k_get_temp_type(3);
917 if (err >= 0)
918 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP4;
919 err = i8k_get_temp_type(4);
920 if (err >= 0)
921 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP5;
922 err = i8k_get_temp_type(5);
923 if (err >= 0)
924 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP6;
925 err = i8k_get_temp_type(6);
926 if (err >= 0)
927 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP7;
928 err = i8k_get_temp_type(7);
929 if (err >= 0)
930 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP8;
931 err = i8k_get_temp_type(8);
932 if (err >= 0)
933 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP9;
934 err = i8k_get_temp_type(9);
935 if (err >= 0)
936 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP10;
937
938 /* First fan attributes, if fan status or type is OK */
939 err = i8k_get_fan_status(0);
940 if (err < 0)
941 err = i8k_get_fan_type(0);
942 if (err >= 0)
943 i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN1;
944
945 /* Second fan attributes, if fan status or type is OK */
946 err = i8k_get_fan_status(1);
947 if (err < 0)
948 err = i8k_get_fan_type(1);
949 if (err >= 0)
950 i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN2;
951
952 /* Third fan attributes, if fan status or type is OK */
953 err = i8k_get_fan_status(2);
954 if (err < 0)
955 err = i8k_get_fan_type(2);
956 if (err >= 0)
957 i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN3;
958
959 i8k_hwmon_dev = hwmon_device_register_with_groups(NULL, "dell_smm",
960 NULL, i8k_groups);
961 if (IS_ERR(i8k_hwmon_dev)) {
962 err = PTR_ERR(i8k_hwmon_dev);
963 i8k_hwmon_dev = NULL;
964 pr_err("hwmon registration failed (%d)\n", err);
965 return err;
966 }
967 return 0;
968}
969
970struct i8k_config_data {
971 uint fan_mult;
972 uint fan_max;
973};
974
975enum i8k_configs {
976 DELL_LATITUDE_D520,
977 DELL_PRECISION_490,
978 DELL_STUDIO,
979 DELL_XPS,
980};
981
982static const struct i8k_config_data i8k_config_data[] = {
983 [DELL_LATITUDE_D520] = {
984 .fan_mult = 1,
985 .fan_max = I8K_FAN_TURBO,
986 },
987 [DELL_PRECISION_490] = {
988 .fan_mult = 1,
989 .fan_max = I8K_FAN_TURBO,
990 },
991 [DELL_STUDIO] = {
992 .fan_mult = 1,
993 .fan_max = I8K_FAN_HIGH,
994 },
995 [DELL_XPS] = {
996 .fan_mult = 1,
997 .fan_max = I8K_FAN_HIGH,
998 },
999};
1000
1001static const struct dmi_system_id i8k_dmi_table[] __initconst = {
1002 {
1003 .ident = "Dell Inspiron",
1004 .matches = {
1005 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
1006 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
1007 },
1008 },
1009 {
1010 .ident = "Dell Latitude",
1011 .matches = {
1012 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
1013 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
1014 },
1015 },
1016 {
1017 .ident = "Dell Inspiron 2",
1018 .matches = {
1019 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1020 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
1021 },
1022 },
1023 {
1024 .ident = "Dell Latitude D520",
1025 .matches = {
1026 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1027 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude D520"),
1028 },
1029 .driver_data = (void *)&i8k_config_data[DELL_LATITUDE_D520],
1030 },
1031 {
1032 .ident = "Dell Latitude 2",
1033 .matches = {
1034 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1035 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
1036 },
1037 },
1038 { /* UK Inspiron 6400 */
1039 .ident = "Dell Inspiron 3",
1040 .matches = {
1041 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1042 DMI_MATCH(DMI_PRODUCT_NAME, "MM061"),
1043 },
1044 },
1045 {
1046 .ident = "Dell Inspiron 3",
1047 .matches = {
1048 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1049 DMI_MATCH(DMI_PRODUCT_NAME, "MP061"),
1050 },
1051 },
1052 {
1053 .ident = "Dell Precision 490",
1054 .matches = {
1055 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1056 DMI_MATCH(DMI_PRODUCT_NAME,
1057 "Precision WorkStation 490"),
1058 },
1059 .driver_data = (void *)&i8k_config_data[DELL_PRECISION_490],
1060 },
1061 {
1062 .ident = "Dell Precision",
1063 .matches = {
1064 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1065 DMI_MATCH(DMI_PRODUCT_NAME, "Precision"),
1066 },
1067 },
1068 {
1069 .ident = "Dell Vostro",
1070 .matches = {
1071 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1072 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
1073 },
1074 },
1075 {
1076 .ident = "Dell Studio",
1077 .matches = {
1078 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1079 DMI_MATCH(DMI_PRODUCT_NAME, "Studio"),
1080 },
1081 .driver_data = (void *)&i8k_config_data[DELL_STUDIO],
1082 },
1083 {
1084 .ident = "Dell XPS M140",
1085 .matches = {
1086 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1087 DMI_MATCH(DMI_PRODUCT_NAME, "MXC051"),
1088 },
1089 .driver_data = (void *)&i8k_config_data[DELL_XPS],
1090 },
1091 {
1092 .ident = "Dell XPS",
1093 .matches = {
1094 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1095 DMI_MATCH(DMI_PRODUCT_NAME, "XPS"),
1096 },
1097 },
1098 { }
1099};
1100
1101MODULE_DEVICE_TABLE(dmi, i8k_dmi_table);
1102
1103/*
1104 * On some machines once I8K_SMM_GET_FAN_TYPE is issued then CPU fan speed
1105 * randomly going up and down due to bug in Dell SMM or BIOS. Here is blacklist
1106 * of affected Dell machines for which we disallow I8K_SMM_GET_FAN_TYPE call.
1107 * See bug: https://bugzilla.kernel.org/show_bug.cgi?id=100121
1108 */
1109static const struct dmi_system_id i8k_blacklist_fan_type_dmi_table[] __initconst = {
1110 {
1111 .ident = "Dell Studio XPS 8000",
1112 .matches = {
1113 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1114 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Studio XPS 8000"),
1115 },
1116 },
1117 {
1118 .ident = "Dell Studio XPS 8100",
1119 .matches = {
1120 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1121 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Studio XPS 8100"),
1122 },
1123 },
1124 {
1125 .ident = "Dell Inspiron 580",
1126 .matches = {
1127 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1128 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Inspiron 580 "),
1129 },
1130 },
1131 { }
1132};
1133
1134/*
1135 * On some machines all fan related SMM functions implemented by Dell BIOS
1136 * firmware freeze kernel for about 500ms. Until Dell fixes these problems fan
1137 * support for affected blacklisted Dell machines stay disabled.
1138 * See bug: https://bugzilla.kernel.org/show_bug.cgi?id=195751
1139 */
1140static struct dmi_system_id i8k_blacklist_fan_support_dmi_table[] __initdata = {
1141 {
1142 .ident = "Dell Inspiron 7720",
1143 .matches = {
1144 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1145 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Inspiron 7720"),
1146 },
1147 },
1148 {
1149 .ident = "Dell Vostro 3360",
1150 .matches = {
1151 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1152 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Vostro 3360"),
1153 },
1154 },
1155 {
1156 .ident = "Dell XPS13 9333",
1157 .matches = {
1158 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1159 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "XPS13 9333"),
1160 },
1161 },
1162 {
1163 .ident = "Dell XPS 15 L502X",
1164 .matches = {
1165 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1166 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L502X"),
1167 },
1168 },
1169 { }
1170};
1171
1172struct i8k_fan_control_data {
1173 unsigned int manual_fan;
1174 unsigned int auto_fan;
1175};
1176
1177enum i8k_fan_controls {
1178 I8K_FAN_34A3_35A3,
1179};
1180
1181static const struct i8k_fan_control_data i8k_fan_control_data[] = {
1182 [I8K_FAN_34A3_35A3] = {
1183 .manual_fan = 0x34a3,
1184 .auto_fan = 0x35a3,
1185 },
1186};
1187
1188static struct dmi_system_id i8k_whitelist_fan_control[] __initdata = {
1189 {
1190 .ident = "Dell Precision 5530",
1191 .matches = {
1192 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1193 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Precision 5530"),
1194 },
1195 .driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
1196 },
1197 {
1198 .ident = "Dell Latitude 5480",
1199 .matches = {
1200 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1201 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude 5480"),
1202 },
1203 .driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
1204 },
1205 {
1206 .ident = "Dell Latitude E6440",
1207 .matches = {
1208 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1209 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude E6440"),
1210 },
1211 .driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
1212 },
1213 {
1214 .ident = "Dell Latitude E7440",
1215 .matches = {
1216 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1217 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude E7440"),
1218 },
1219 .driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
1220 },
1221 { }
1222};
1223
1224/*
1225 * Probe for the presence of a supported laptop.
1226 */
1227static int __init i8k_probe(void)
1228{
1229 const struct dmi_system_id *id, *fan_control;
1230 int fan, ret;
1231
1232 /*
1233 * Get DMI information
1234 */
1235 if (!dmi_check_system(i8k_dmi_table)) {
1236 if (!ignore_dmi && !force)
1237 return -ENODEV;
1238
1239 pr_info("not running on a supported Dell system.\n");
1240 pr_info("vendor=%s, model=%s, version=%s\n",
1241 i8k_get_dmi_data(DMI_SYS_VENDOR),
1242 i8k_get_dmi_data(DMI_PRODUCT_NAME),
1243 i8k_get_dmi_data(DMI_BIOS_VERSION));
1244 }
1245
1246 if (dmi_check_system(i8k_blacklist_fan_support_dmi_table)) {
1247 pr_warn("broken Dell BIOS detected, disallow fan support\n");
1248 if (!force)
1249 disallow_fan_support = true;
1250 }
1251
1252 if (dmi_check_system(i8k_blacklist_fan_type_dmi_table)) {
1253 pr_warn("broken Dell BIOS detected, disallow fan type call\n");
1254 if (!force)
1255 disallow_fan_type_call = true;
1256 }
1257
1258 strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION),
1259 sizeof(bios_version));
1260 strlcpy(bios_machineid, i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
1261 sizeof(bios_machineid));
1262
1263 /*
1264 * Get SMM Dell signature
1265 */
1266 if (i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG1) &&
1267 i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) {
1268 pr_err("unable to get SMM Dell signature\n");
1269 if (!force)
1270 return -ENODEV;
1271 }
1272
1273 /*
1274 * Set fan multiplier and maximal fan speed from dmi config
1275 * Values specified in module parameters override values from dmi
1276 */
1277 id = dmi_first_match(i8k_dmi_table);
1278 if (id && id->driver_data) {
1279 const struct i8k_config_data *conf = id->driver_data;
1280 if (!fan_mult && conf->fan_mult)
1281 fan_mult = conf->fan_mult;
1282 if (!fan_max && conf->fan_max)
1283 fan_max = conf->fan_max;
1284 }
1285
1286 i8k_fan_max = fan_max ? : I8K_FAN_HIGH; /* Must not be 0 */
1287 i8k_pwm_mult = DIV_ROUND_UP(255, i8k_fan_max);
1288
1289 fan_control = dmi_first_match(i8k_whitelist_fan_control);
1290 if (fan_control && fan_control->driver_data) {
1291 const struct i8k_fan_control_data *data = fan_control->driver_data;
1292
1293 manual_fan = data->manual_fan;
1294 auto_fan = data->auto_fan;
1295 pr_info("enabling support for setting automatic/manual fan control\n");
1296 }
1297
1298 if (!fan_mult) {
1299 /*
1300 * Autodetect fan multiplier based on nominal rpm
1301 * If fan reports rpm value too high then set multiplier to 1
1302 */
1303 for (fan = 0; fan < 2; ++fan) {
1304 ret = i8k_get_fan_nominal_speed(fan, i8k_fan_max);
1305 if (ret < 0)
1306 continue;
1307 if (ret > I8K_FAN_MAX_RPM)
1308 i8k_fan_mult = 1;
1309 break;
1310 }
1311 } else {
1312 /* Fan multiplier was specified in module param or in dmi */
1313 i8k_fan_mult = fan_mult;
1314 }
1315
1316 return 0;
1317}
1318
1319static int __init i8k_init(void)
1320{
1321 int err;
1322
1323 /* Are we running on an supported laptop? */
1324 if (i8k_probe())
1325 return -ENODEV;
1326
1327 err = i8k_init_hwmon();
1328 if (err)
1329 return err;
1330
1331 i8k_init_procfs();
1332 return 0;
1333}
1334
1335static void __exit i8k_exit(void)
1336{
1337 hwmon_device_unregister(i8k_hwmon_dev);
1338 i8k_exit_procfs();
1339}
1340
1341module_init(i8k_init);
1342module_exit(i8k_exit);