1 /*
2 * dell-smm-hwmon.c -- Linux driver for accessing the SMM BIOS on Dell laptops.
3 *
4 * Copyright (C) 2001 Massimo Dal Zotto <dz@debian.org>
5 *
6 * Hwmon integration:
7 * Copyright (C) 2011 Jean Delvare <jdelvare@suse.de>
8 * Copyright (C) 2013, 2014 Guenter Roeck <linux@roeck-us.net>
9 * Copyright (C) 2014, 2015 Pali Rohár <pali.rohar@gmail.com>
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the
13 * Free Software Foundation; either version 2, or (at your option) any
14 * later version.
15 *
16 * This program is distributed in the hope that it will be useful, but
17 * WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * General Public License for more details.
20 */
21
22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23
24 #include <linux/cpu.h>
25 #include <linux/delay.h>
26 #include <linux/module.h>
27 #include <linux/types.h>
28 #include <linux/init.h>
29 #include <linux/proc_fs.h>
30 #include <linux/seq_file.h>
31 #include <linux/dmi.h>
32 #include <linux/capability.h>
33 #include <linux/mutex.h>
34 #include <linux/hwmon.h>
35 #include <linux/hwmon-sysfs.h>
36 #include <linux/uaccess.h>
37 #include <linux/io.h>
38 #include <linux/sched.h>
39 #include <linux/ctype.h>
40 #include <linux/smp.h>
41
42 #include <linux/i8k.h>
43
44 #define I8K_SMM_FN_STATUS 0x0025
45 #define I8K_SMM_POWER_STATUS 0x0069
46 #define I8K_SMM_SET_FAN 0x01a3
47 #define I8K_SMM_GET_FAN 0x00a3
48 #define I8K_SMM_GET_SPEED 0x02a3
49 #define I8K_SMM_GET_FAN_TYPE 0x03a3
50 #define I8K_SMM_GET_NOM_SPEED 0x04a3
51 #define I8K_SMM_GET_TEMP 0x10a3
52 #define I8K_SMM_GET_TEMP_TYPE 0x11a3
53 #define I8K_SMM_GET_DELL_SIG1 0xfea3
54 #define I8K_SMM_GET_DELL_SIG2 0xffa3
55
56 #define I8K_FAN_MULT 30
57 #define I8K_FAN_MAX_RPM 30000
58 #define I8K_MAX_TEMP 127
59
60 #define I8K_FN_NONE 0x00
61 #define I8K_FN_UP 0x01
62 #define I8K_FN_DOWN 0x02
63 #define I8K_FN_MUTE 0x04
64 #define I8K_FN_MASK 0x07
65 #define I8K_FN_SHIFT 8
66
67 #define I8K_POWER_AC 0x05
68 #define I8K_POWER_BATTERY 0x01
69
70 static DEFINE_MUTEX(i8k_mutex);
71 static char bios_version[4];
72 static char bios_machineid[16];
73 static struct device *i8k_hwmon_dev;
74 static u32 i8k_hwmon_flags;
75 static uint i8k_fan_mult = I8K_FAN_MULT;
76 static uint i8k_pwm_mult;
77 static uint i8k_fan_max = I8K_FAN_HIGH;
78 static bool disallow_fan_type_call;
79 static bool disallow_fan_support;
80
81 #define I8K_HWMON_HAVE_TEMP1 (1 << 0)
82 #define I8K_HWMON_HAVE_TEMP2 (1 << 1)
83 #define I8K_HWMON_HAVE_TEMP3 (1 << 2)
84 #define I8K_HWMON_HAVE_TEMP4 (1 << 3)
85 #define I8K_HWMON_HAVE_FAN1 (1 << 4)
86 #define I8K_HWMON_HAVE_FAN2 (1 << 5)
87 #define I8K_HWMON_HAVE_FAN3 (1 << 6)
88
89 MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
90 MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
91 MODULE_DESCRIPTION("Dell laptop SMM BIOS hwmon driver");
92 MODULE_LICENSE("GPL");
93 MODULE_ALIAS("i8k");
94
95 static bool force;
96 module_param(force, bool, 0);
97 MODULE_PARM_DESC(force, "Force loading without checking for supported models");
98
99 static bool ignore_dmi;
100 module_param(ignore_dmi, bool, 0);
101 MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
102
103 #if IS_ENABLED(CONFIG_I8K)
104 static bool restricted = true;
105 module_param(restricted, bool, 0);
106 MODULE_PARM_DESC(restricted, "Restrict fan control and serial number to CAP_SYS_ADMIN (default: 1)");
107
108 static bool power_status;
109 module_param(power_status, bool, 0600);
110 MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k (default: 0)");
111 #endif
112
113 static uint fan_mult;
114 module_param(fan_mult, uint, 0);
115 MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with (default: autodetect)");
116
117 static uint fan_max;
118 module_param(fan_max, uint, 0);
119 MODULE_PARM_DESC(fan_max, "Maximum configurable fan speed (default: autodetect)");
120
121 struct smm_regs {
122 unsigned int eax;
123 unsigned int ebx __packed;
124 unsigned int ecx __packed;
125 unsigned int edx __packed;
126 unsigned int esi __packed;
127 unsigned int edi __packed;
128 };
129
i8k_get_dmi_data(int field)130 static inline const char *i8k_get_dmi_data(int field)
131 {
132 const char *dmi_data = dmi_get_system_info(field);
133
134 return dmi_data && *dmi_data ? dmi_data : "?";
135 }
136
137 /*
138 * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard.
139 */
i8k_smm_func(void * par)140 static int i8k_smm_func(void *par)
141 {
142 int rc;
143 struct smm_regs *regs = par;
144 int eax = regs->eax;
145
146 #ifdef DEBUG
147 int ebx = regs->ebx;
148 unsigned long duration;
149 ktime_t calltime, delta, rettime;
150
151 calltime = ktime_get();
152 #endif
153
154 /* SMM requires CPU 0 */
155 if (smp_processor_id() != 0)
156 return -EBUSY;
157
158 #if defined(CONFIG_X86_64)
159 asm volatile("pushq %%rax\n\t"
160 "movl 0(%%rax),%%edx\n\t"
161 "pushq %%rdx\n\t"
162 "movl 4(%%rax),%%ebx\n\t"
163 "movl 8(%%rax),%%ecx\n\t"
164 "movl 12(%%rax),%%edx\n\t"
165 "movl 16(%%rax),%%esi\n\t"
166 "movl 20(%%rax),%%edi\n\t"
167 "popq %%rax\n\t"
168 "out %%al,$0xb2\n\t"
169 "out %%al,$0x84\n\t"
170 "xchgq %%rax,(%%rsp)\n\t"
171 "movl %%ebx,4(%%rax)\n\t"
172 "movl %%ecx,8(%%rax)\n\t"
173 "movl %%edx,12(%%rax)\n\t"
174 "movl %%esi,16(%%rax)\n\t"
175 "movl %%edi,20(%%rax)\n\t"
176 "popq %%rdx\n\t"
177 "movl %%edx,0(%%rax)\n\t"
178 "pushfq\n\t"
179 "popq %%rax\n\t"
180 "andl $1,%%eax\n"
181 : "=a"(rc)
182 : "a"(regs)
183 : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
184 #else
185 asm volatile("pushl %%eax\n\t"
186 "movl 0(%%eax),%%edx\n\t"
187 "push %%edx\n\t"
188 "movl 4(%%eax),%%ebx\n\t"
189 "movl 8(%%eax),%%ecx\n\t"
190 "movl 12(%%eax),%%edx\n\t"
191 "movl 16(%%eax),%%esi\n\t"
192 "movl 20(%%eax),%%edi\n\t"
193 "popl %%eax\n\t"
194 "out %%al,$0xb2\n\t"
195 "out %%al,$0x84\n\t"
196 "xchgl %%eax,(%%esp)\n\t"
197 "movl %%ebx,4(%%eax)\n\t"
198 "movl %%ecx,8(%%eax)\n\t"
199 "movl %%edx,12(%%eax)\n\t"
200 "movl %%esi,16(%%eax)\n\t"
201 "movl %%edi,20(%%eax)\n\t"
202 "popl %%edx\n\t"
203 "movl %%edx,0(%%eax)\n\t"
204 "lahf\n\t"
205 "shrl $8,%%eax\n\t"
206 "andl $1,%%eax\n"
207 : "=a"(rc)
208 : "a"(regs)
209 : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
210 #endif
211 if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
212 rc = -EINVAL;
213
214 #ifdef DEBUG
215 rettime = ktime_get();
216 delta = ktime_sub(rettime, calltime);
217 duration = ktime_to_ns(delta) >> 10;
218 pr_debug("smm(0x%.4x 0x%.4x) = 0x%.4x (took %7lu usecs)\n", eax, ebx,
219 (rc ? 0xffff : regs->eax & 0xffff), duration);
220 #endif
221
222 return rc;
223 }
224
225 /*
226 * Call the System Management Mode BIOS.
227 */
i8k_smm(struct smm_regs * regs)228 static int i8k_smm(struct smm_regs *regs)
229 {
230 int ret;
231
232 get_online_cpus();
233 ret = smp_call_on_cpu(0, i8k_smm_func, regs, true);
234 put_online_cpus();
235
236 return ret;
237 }
238
239 /*
240 * Read the fan status.
241 */
i8k_get_fan_status(int fan)242 static int i8k_get_fan_status(int fan)
243 {
244 struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, };
245
246 if (disallow_fan_support)
247 return -EINVAL;
248
249 regs.ebx = fan & 0xff;
250 return i8k_smm(®s) ? : regs.eax & 0xff;
251 }
252
253 /*
254 * Read the fan speed in RPM.
255 */
i8k_get_fan_speed(int fan)256 static int i8k_get_fan_speed(int fan)
257 {
258 struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, };
259
260 if (disallow_fan_support)
261 return -EINVAL;
262
263 regs.ebx = fan & 0xff;
264 return i8k_smm(®s) ? : (regs.eax & 0xffff) * i8k_fan_mult;
265 }
266
267 /*
268 * Read the fan type.
269 */
_i8k_get_fan_type(int fan)270 static int _i8k_get_fan_type(int fan)
271 {
272 struct smm_regs regs = { .eax = I8K_SMM_GET_FAN_TYPE, };
273
274 if (disallow_fan_support || disallow_fan_type_call)
275 return -EINVAL;
276
277 regs.ebx = fan & 0xff;
278 return i8k_smm(®s) ? : regs.eax & 0xff;
279 }
280
i8k_get_fan_type(int fan)281 static int i8k_get_fan_type(int fan)
282 {
283 /* I8K_SMM_GET_FAN_TYPE SMM call is expensive, so cache values */
284 static int types[3] = { INT_MIN, INT_MIN, INT_MIN };
285
286 if (types[fan] == INT_MIN)
287 types[fan] = _i8k_get_fan_type(fan);
288
289 return types[fan];
290 }
291
292 /*
293 * Read the fan nominal rpm for specific fan speed.
294 */
i8k_get_fan_nominal_speed(int fan,int speed)295 static int i8k_get_fan_nominal_speed(int fan, int speed)
296 {
297 struct smm_regs regs = { .eax = I8K_SMM_GET_NOM_SPEED, };
298
299 if (disallow_fan_support)
300 return -EINVAL;
301
302 regs.ebx = (fan & 0xff) | (speed << 8);
303 return i8k_smm(®s) ? : (regs.eax & 0xffff) * i8k_fan_mult;
304 }
305
306 /*
307 * Set the fan speed (off, low, high). Returns the new fan status.
308 */
i8k_set_fan(int fan,int speed)309 static int i8k_set_fan(int fan, int speed)
310 {
311 struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
312
313 if (disallow_fan_support)
314 return -EINVAL;
315
316 speed = (speed < 0) ? 0 : ((speed > i8k_fan_max) ? i8k_fan_max : speed);
317 regs.ebx = (fan & 0xff) | (speed << 8);
318
319 return i8k_smm(®s) ? : i8k_get_fan_status(fan);
320 }
321
i8k_get_temp_type(int sensor)322 static int i8k_get_temp_type(int sensor)
323 {
324 struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP_TYPE, };
325
326 regs.ebx = sensor & 0xff;
327 return i8k_smm(®s) ? : regs.eax & 0xff;
328 }
329
330 /*
331 * Read the cpu temperature.
332 */
_i8k_get_temp(int sensor)333 static int _i8k_get_temp(int sensor)
334 {
335 struct smm_regs regs = {
336 .eax = I8K_SMM_GET_TEMP,
337 .ebx = sensor & 0xff,
338 };
339
340 return i8k_smm(®s) ? : regs.eax & 0xff;
341 }
342
i8k_get_temp(int sensor)343 static int i8k_get_temp(int sensor)
344 {
345 int temp = _i8k_get_temp(sensor);
346
347 /*
348 * Sometimes the temperature sensor returns 0x99, which is out of range.
349 * In this case we retry (once) before returning an error.
350 # 1003655137 00000058 00005a4b
351 # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
352 # 1003655139 00000054 00005c52
353 */
354 if (temp == 0x99) {
355 msleep(100);
356 temp = _i8k_get_temp(sensor);
357 }
358 /*
359 * Return -ENODATA for all invalid temperatures.
360 *
361 * Known instances are the 0x99 value as seen above as well as
362 * 0xc1 (193), which may be returned when trying to read the GPU
363 * temperature if the system supports a GPU and it is currently
364 * turned off.
365 */
366 if (temp > I8K_MAX_TEMP)
367 return -ENODATA;
368
369 return temp;
370 }
371
i8k_get_dell_signature(int req_fn)372 static int i8k_get_dell_signature(int req_fn)
373 {
374 struct smm_regs regs = { .eax = req_fn, };
375 int rc;
376
377 rc = i8k_smm(®s);
378 if (rc < 0)
379 return rc;
380
381 return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
382 }
383
384 #if IS_ENABLED(CONFIG_I8K)
385
386 /*
387 * Read the Fn key status.
388 */
i8k_get_fn_status(void)389 static int i8k_get_fn_status(void)
390 {
391 struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, };
392 int rc;
393
394 rc = i8k_smm(®s);
395 if (rc < 0)
396 return rc;
397
398 switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) {
399 case I8K_FN_UP:
400 return I8K_VOL_UP;
401 case I8K_FN_DOWN:
402 return I8K_VOL_DOWN;
403 case I8K_FN_MUTE:
404 return I8K_VOL_MUTE;
405 default:
406 return 0;
407 }
408 }
409
410 /*
411 * Read the power status.
412 */
i8k_get_power_status(void)413 static int i8k_get_power_status(void)
414 {
415 struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, };
416 int rc;
417
418 rc = i8k_smm(®s);
419 if (rc < 0)
420 return rc;
421
422 return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY;
423 }
424
425 /*
426 * Procfs interface
427 */
428
429 static int
i8k_ioctl_unlocked(struct file * fp,unsigned int cmd,unsigned long arg)430 i8k_ioctl_unlocked(struct file *fp, unsigned int cmd, unsigned long arg)
431 {
432 int val = 0;
433 int speed;
434 unsigned char buff[16];
435 int __user *argp = (int __user *)arg;
436
437 if (!argp)
438 return -EINVAL;
439
440 switch (cmd) {
441 case I8K_BIOS_VERSION:
442 if (!isdigit(bios_version[0]) || !isdigit(bios_version[1]) ||
443 !isdigit(bios_version[2]))
444 return -EINVAL;
445
446 val = (bios_version[0] << 16) |
447 (bios_version[1] << 8) | bios_version[2];
448 break;
449
450 case I8K_MACHINE_ID:
451 if (restricted && !capable(CAP_SYS_ADMIN))
452 return -EPERM;
453
454 memset(buff, 0, sizeof(buff));
455 strlcpy(buff, bios_machineid, sizeof(buff));
456 break;
457
458 case I8K_FN_STATUS:
459 val = i8k_get_fn_status();
460 break;
461
462 case I8K_POWER_STATUS:
463 val = i8k_get_power_status();
464 break;
465
466 case I8K_GET_TEMP:
467 val = i8k_get_temp(0);
468 break;
469
470 case I8K_GET_SPEED:
471 if (copy_from_user(&val, argp, sizeof(int)))
472 return -EFAULT;
473
474 val = i8k_get_fan_speed(val);
475 break;
476
477 case I8K_GET_FAN:
478 if (copy_from_user(&val, argp, sizeof(int)))
479 return -EFAULT;
480
481 val = i8k_get_fan_status(val);
482 break;
483
484 case I8K_SET_FAN:
485 if (restricted && !capable(CAP_SYS_ADMIN))
486 return -EPERM;
487
488 if (copy_from_user(&val, argp, sizeof(int)))
489 return -EFAULT;
490
491 if (copy_from_user(&speed, argp + 1, sizeof(int)))
492 return -EFAULT;
493
494 val = i8k_set_fan(val, speed);
495 break;
496
497 default:
498 return -EINVAL;
499 }
500
501 if (val < 0)
502 return val;
503
504 switch (cmd) {
505 case I8K_BIOS_VERSION:
506 if (copy_to_user(argp, &val, 4))
507 return -EFAULT;
508
509 break;
510 case I8K_MACHINE_ID:
511 if (copy_to_user(argp, buff, 16))
512 return -EFAULT;
513
514 break;
515 default:
516 if (copy_to_user(argp, &val, sizeof(int)))
517 return -EFAULT;
518
519 break;
520 }
521
522 return 0;
523 }
524
i8k_ioctl(struct file * fp,unsigned int cmd,unsigned long arg)525 static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
526 {
527 long ret;
528
529 mutex_lock(&i8k_mutex);
530 ret = i8k_ioctl_unlocked(fp, cmd, arg);
531 mutex_unlock(&i8k_mutex);
532
533 return ret;
534 }
535
536 /*
537 * Print the information for /proc/i8k.
538 */
i8k_proc_show(struct seq_file * seq,void * offset)539 static int i8k_proc_show(struct seq_file *seq, void *offset)
540 {
541 int fn_key, cpu_temp, ac_power;
542 int left_fan, right_fan, left_speed, right_speed;
543
544 cpu_temp = i8k_get_temp(0); /* 11100 µs */
545 left_fan = i8k_get_fan_status(I8K_FAN_LEFT); /* 580 µs */
546 right_fan = i8k_get_fan_status(I8K_FAN_RIGHT); /* 580 µs */
547 left_speed = i8k_get_fan_speed(I8K_FAN_LEFT); /* 580 µs */
548 right_speed = i8k_get_fan_speed(I8K_FAN_RIGHT); /* 580 µs */
549 fn_key = i8k_get_fn_status(); /* 750 µs */
550 if (power_status)
551 ac_power = i8k_get_power_status(); /* 14700 µs */
552 else
553 ac_power = -1;
554
555 /*
556 * Info:
557 *
558 * 1) Format version (this will change if format changes)
559 * 2) BIOS version
560 * 3) BIOS machine ID
561 * 4) Cpu temperature
562 * 5) Left fan status
563 * 6) Right fan status
564 * 7) Left fan speed
565 * 8) Right fan speed
566 * 9) AC power
567 * 10) Fn Key status
568 */
569 seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
570 I8K_PROC_FMT,
571 bios_version,
572 (restricted && !capable(CAP_SYS_ADMIN)) ? "-1" : bios_machineid,
573 cpu_temp,
574 left_fan, right_fan, left_speed, right_speed,
575 ac_power, fn_key);
576
577 return 0;
578 }
579
i8k_open_fs(struct inode * inode,struct file * file)580 static int i8k_open_fs(struct inode *inode, struct file *file)
581 {
582 return single_open(file, i8k_proc_show, NULL);
583 }
584
585 static const struct file_operations i8k_fops = {
586 .owner = THIS_MODULE,
587 .open = i8k_open_fs,
588 .read = seq_read,
589 .llseek = seq_lseek,
590 .release = single_release,
591 .unlocked_ioctl = i8k_ioctl,
592 };
593
i8k_init_procfs(void)594 static void __init i8k_init_procfs(void)
595 {
596 /* Register the proc entry */
597 proc_create("i8k", 0, NULL, &i8k_fops);
598 }
599
i8k_exit_procfs(void)600 static void __exit i8k_exit_procfs(void)
601 {
602 remove_proc_entry("i8k", NULL);
603 }
604
605 #else
606
i8k_init_procfs(void)607 static inline void __init i8k_init_procfs(void)
608 {
609 }
610
i8k_exit_procfs(void)611 static inline void __exit i8k_exit_procfs(void)
612 {
613 }
614
615 #endif
616
617 /*
618 * Hwmon interface
619 */
620
i8k_hwmon_show_temp_label(struct device * dev,struct device_attribute * devattr,char * buf)621 static ssize_t i8k_hwmon_show_temp_label(struct device *dev,
622 struct device_attribute *devattr,
623 char *buf)
624 {
625 static const char * const labels[] = {
626 "CPU",
627 "GPU",
628 "SODIMM",
629 "Other",
630 "Ambient",
631 "Other",
632 };
633 int index = to_sensor_dev_attr(devattr)->index;
634 int type;
635
636 type = i8k_get_temp_type(index);
637 if (type < 0)
638 return type;
639 if (type >= ARRAY_SIZE(labels))
640 type = ARRAY_SIZE(labels) - 1;
641 return sprintf(buf, "%s\n", labels[type]);
642 }
643
i8k_hwmon_show_temp(struct device * dev,struct device_attribute * devattr,char * buf)644 static ssize_t i8k_hwmon_show_temp(struct device *dev,
645 struct device_attribute *devattr,
646 char *buf)
647 {
648 int index = to_sensor_dev_attr(devattr)->index;
649 int temp;
650
651 temp = i8k_get_temp(index);
652 if (temp < 0)
653 return temp;
654 return sprintf(buf, "%d\n", temp * 1000);
655 }
656
i8k_hwmon_show_fan_label(struct device * dev,struct device_attribute * devattr,char * buf)657 static ssize_t i8k_hwmon_show_fan_label(struct device *dev,
658 struct device_attribute *devattr,
659 char *buf)
660 {
661 static const char * const labels[] = {
662 "Processor Fan",
663 "Motherboard Fan",
664 "Video Fan",
665 "Power Supply Fan",
666 "Chipset Fan",
667 "Other Fan",
668 };
669 int index = to_sensor_dev_attr(devattr)->index;
670 bool dock = false;
671 int type;
672
673 type = i8k_get_fan_type(index);
674 if (type < 0)
675 return type;
676
677 if (type & 0x10) {
678 dock = true;
679 type &= 0x0F;
680 }
681
682 if (type >= ARRAY_SIZE(labels))
683 type = (ARRAY_SIZE(labels) - 1);
684
685 return sprintf(buf, "%s%s\n", (dock ? "Docking " : ""), labels[type]);
686 }
687
i8k_hwmon_show_fan(struct device * dev,struct device_attribute * devattr,char * buf)688 static ssize_t i8k_hwmon_show_fan(struct device *dev,
689 struct device_attribute *devattr,
690 char *buf)
691 {
692 int index = to_sensor_dev_attr(devattr)->index;
693 int fan_speed;
694
695 fan_speed = i8k_get_fan_speed(index);
696 if (fan_speed < 0)
697 return fan_speed;
698 return sprintf(buf, "%d\n", fan_speed);
699 }
700
i8k_hwmon_show_pwm(struct device * dev,struct device_attribute * devattr,char * buf)701 static ssize_t i8k_hwmon_show_pwm(struct device *dev,
702 struct device_attribute *devattr,
703 char *buf)
704 {
705 int index = to_sensor_dev_attr(devattr)->index;
706 int status;
707
708 status = i8k_get_fan_status(index);
709 if (status < 0)
710 return -EIO;
711 return sprintf(buf, "%d\n", clamp_val(status * i8k_pwm_mult, 0, 255));
712 }
713
i8k_hwmon_set_pwm(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)714 static ssize_t i8k_hwmon_set_pwm(struct device *dev,
715 struct device_attribute *attr,
716 const char *buf, size_t count)
717 {
718 int index = to_sensor_dev_attr(attr)->index;
719 unsigned long val;
720 int err;
721
722 err = kstrtoul(buf, 10, &val);
723 if (err)
724 return err;
725 val = clamp_val(DIV_ROUND_CLOSEST(val, i8k_pwm_mult), 0, i8k_fan_max);
726
727 mutex_lock(&i8k_mutex);
728 err = i8k_set_fan(index, val);
729 mutex_unlock(&i8k_mutex);
730
731 return err < 0 ? -EIO : count;
732 }
733
734 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 0);
735 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
736 0);
737 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 1);
738 static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
739 1);
740 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 2);
741 static SENSOR_DEVICE_ATTR(temp3_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
742 2);
743 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 3);
744 static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
745 3);
746 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, i8k_hwmon_show_fan, NULL, 0);
747 static SENSOR_DEVICE_ATTR(fan1_label, S_IRUGO, i8k_hwmon_show_fan_label, NULL,
748 0);
749 static SENSOR_DEVICE_ATTR(pwm1, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
750 i8k_hwmon_set_pwm, 0);
751 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
752 1);
753 static SENSOR_DEVICE_ATTR(fan2_label, S_IRUGO, i8k_hwmon_show_fan_label, NULL,
754 1);
755 static SENSOR_DEVICE_ATTR(pwm2, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
756 i8k_hwmon_set_pwm, 1);
757 static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
758 2);
759 static SENSOR_DEVICE_ATTR(fan3_label, S_IRUGO, i8k_hwmon_show_fan_label, NULL,
760 2);
761 static SENSOR_DEVICE_ATTR(pwm3, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
762 i8k_hwmon_set_pwm, 2);
763
764 static struct attribute *i8k_attrs[] = {
765 &sensor_dev_attr_temp1_input.dev_attr.attr, /* 0 */
766 &sensor_dev_attr_temp1_label.dev_attr.attr, /* 1 */
767 &sensor_dev_attr_temp2_input.dev_attr.attr, /* 2 */
768 &sensor_dev_attr_temp2_label.dev_attr.attr, /* 3 */
769 &sensor_dev_attr_temp3_input.dev_attr.attr, /* 4 */
770 &sensor_dev_attr_temp3_label.dev_attr.attr, /* 5 */
771 &sensor_dev_attr_temp4_input.dev_attr.attr, /* 6 */
772 &sensor_dev_attr_temp4_label.dev_attr.attr, /* 7 */
773 &sensor_dev_attr_fan1_input.dev_attr.attr, /* 8 */
774 &sensor_dev_attr_fan1_label.dev_attr.attr, /* 9 */
775 &sensor_dev_attr_pwm1.dev_attr.attr, /* 10 */
776 &sensor_dev_attr_fan2_input.dev_attr.attr, /* 11 */
777 &sensor_dev_attr_fan2_label.dev_attr.attr, /* 12 */
778 &sensor_dev_attr_pwm2.dev_attr.attr, /* 13 */
779 &sensor_dev_attr_fan3_input.dev_attr.attr, /* 14 */
780 &sensor_dev_attr_fan3_label.dev_attr.attr, /* 15 */
781 &sensor_dev_attr_pwm3.dev_attr.attr, /* 16 */
782 NULL
783 };
784
i8k_is_visible(struct kobject * kobj,struct attribute * attr,int index)785 static umode_t i8k_is_visible(struct kobject *kobj, struct attribute *attr,
786 int index)
787 {
788 if (disallow_fan_support && index >= 8)
789 return 0;
790 if (disallow_fan_type_call &&
791 (index == 9 || index == 12 || index == 15))
792 return 0;
793 if (index >= 0 && index <= 1 &&
794 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP1))
795 return 0;
796 if (index >= 2 && index <= 3 &&
797 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP2))
798 return 0;
799 if (index >= 4 && index <= 5 &&
800 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP3))
801 return 0;
802 if (index >= 6 && index <= 7 &&
803 !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP4))
804 return 0;
805 if (index >= 8 && index <= 10 &&
806 !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN1))
807 return 0;
808 if (index >= 11 && index <= 13 &&
809 !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN2))
810 return 0;
811 if (index >= 14 && index <= 16 &&
812 !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN3))
813 return 0;
814
815 return attr->mode;
816 }
817
818 static const struct attribute_group i8k_group = {
819 .attrs = i8k_attrs,
820 .is_visible = i8k_is_visible,
821 };
822 __ATTRIBUTE_GROUPS(i8k);
823
i8k_init_hwmon(void)824 static int __init i8k_init_hwmon(void)
825 {
826 int err;
827
828 i8k_hwmon_flags = 0;
829
830 /* CPU temperature attributes, if temperature type is OK */
831 err = i8k_get_temp_type(0);
832 if (err >= 0)
833 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP1;
834 /* check for additional temperature sensors */
835 err = i8k_get_temp_type(1);
836 if (err >= 0)
837 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP2;
838 err = i8k_get_temp_type(2);
839 if (err >= 0)
840 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP3;
841 err = i8k_get_temp_type(3);
842 if (err >= 0)
843 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP4;
844
845 /* First fan attributes, if fan status or type is OK */
846 err = i8k_get_fan_status(0);
847 if (err < 0)
848 err = i8k_get_fan_type(0);
849 if (err >= 0)
850 i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN1;
851
852 /* Second fan attributes, if fan status or type is OK */
853 err = i8k_get_fan_status(1);
854 if (err < 0)
855 err = i8k_get_fan_type(1);
856 if (err >= 0)
857 i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN2;
858
859 /* Third fan attributes, if fan status or type is OK */
860 err = i8k_get_fan_status(2);
861 if (err < 0)
862 err = i8k_get_fan_type(2);
863 if (err >= 0)
864 i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN3;
865
866 i8k_hwmon_dev = hwmon_device_register_with_groups(NULL, "dell_smm",
867 NULL, i8k_groups);
868 if (IS_ERR(i8k_hwmon_dev)) {
869 err = PTR_ERR(i8k_hwmon_dev);
870 i8k_hwmon_dev = NULL;
871 pr_err("hwmon registration failed (%d)\n", err);
872 return err;
873 }
874 return 0;
875 }
876
877 struct i8k_config_data {
878 uint fan_mult;
879 uint fan_max;
880 };
881
882 enum i8k_configs {
883 DELL_LATITUDE_D520,
884 DELL_PRECISION_490,
885 DELL_STUDIO,
886 DELL_XPS,
887 };
888
889 static const struct i8k_config_data i8k_config_data[] = {
890 [DELL_LATITUDE_D520] = {
891 .fan_mult = 1,
892 .fan_max = I8K_FAN_TURBO,
893 },
894 [DELL_PRECISION_490] = {
895 .fan_mult = 1,
896 .fan_max = I8K_FAN_TURBO,
897 },
898 [DELL_STUDIO] = {
899 .fan_mult = 1,
900 .fan_max = I8K_FAN_HIGH,
901 },
902 [DELL_XPS] = {
903 .fan_mult = 1,
904 .fan_max = I8K_FAN_HIGH,
905 },
906 };
907
908 static const struct dmi_system_id i8k_dmi_table[] __initconst = {
909 {
910 .ident = "Dell Inspiron",
911 .matches = {
912 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
913 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
914 },
915 },
916 {
917 .ident = "Dell Latitude",
918 .matches = {
919 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
920 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
921 },
922 },
923 {
924 .ident = "Dell Inspiron 2",
925 .matches = {
926 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
927 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
928 },
929 },
930 {
931 .ident = "Dell Latitude D520",
932 .matches = {
933 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
934 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude D520"),
935 },
936 .driver_data = (void *)&i8k_config_data[DELL_LATITUDE_D520],
937 },
938 {
939 .ident = "Dell Latitude 2",
940 .matches = {
941 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
942 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
943 },
944 },
945 { /* UK Inspiron 6400 */
946 .ident = "Dell Inspiron 3",
947 .matches = {
948 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
949 DMI_MATCH(DMI_PRODUCT_NAME, "MM061"),
950 },
951 },
952 {
953 .ident = "Dell Inspiron 3",
954 .matches = {
955 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
956 DMI_MATCH(DMI_PRODUCT_NAME, "MP061"),
957 },
958 },
959 {
960 .ident = "Dell Precision 490",
961 .matches = {
962 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
963 DMI_MATCH(DMI_PRODUCT_NAME,
964 "Precision WorkStation 490"),
965 },
966 .driver_data = (void *)&i8k_config_data[DELL_PRECISION_490],
967 },
968 {
969 .ident = "Dell Precision",
970 .matches = {
971 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
972 DMI_MATCH(DMI_PRODUCT_NAME, "Precision"),
973 },
974 },
975 {
976 .ident = "Dell Vostro",
977 .matches = {
978 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
979 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
980 },
981 },
982 {
983 .ident = "Dell XPS421",
984 .matches = {
985 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
986 DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
987 },
988 },
989 {
990 .ident = "Dell Studio",
991 .matches = {
992 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
993 DMI_MATCH(DMI_PRODUCT_NAME, "Studio"),
994 },
995 .driver_data = (void *)&i8k_config_data[DELL_STUDIO],
996 },
997 {
998 .ident = "Dell XPS 13",
999 .matches = {
1000 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1001 DMI_MATCH(DMI_PRODUCT_NAME, "XPS13"),
1002 },
1003 .driver_data = (void *)&i8k_config_data[DELL_XPS],
1004 },
1005 {
1006 .ident = "Dell XPS M140",
1007 .matches = {
1008 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1009 DMI_MATCH(DMI_PRODUCT_NAME, "MXC051"),
1010 },
1011 .driver_data = (void *)&i8k_config_data[DELL_XPS],
1012 },
1013 {
1014 .ident = "Dell XPS 15 9560",
1015 .matches = {
1016 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1017 DMI_MATCH(DMI_PRODUCT_NAME, "XPS 15 9560"),
1018 },
1019 },
1020 { }
1021 };
1022
1023 MODULE_DEVICE_TABLE(dmi, i8k_dmi_table);
1024
1025 /*
1026 * On some machines once I8K_SMM_GET_FAN_TYPE is issued then CPU fan speed
1027 * randomly going up and down due to bug in Dell SMM or BIOS. Here is blacklist
1028 * of affected Dell machines for which we disallow I8K_SMM_GET_FAN_TYPE call.
1029 * See bug: https://bugzilla.kernel.org/show_bug.cgi?id=100121
1030 */
1031 static const struct dmi_system_id i8k_blacklist_fan_type_dmi_table[] __initconst = {
1032 {
1033 .ident = "Dell Studio XPS 8000",
1034 .matches = {
1035 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1036 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Studio XPS 8000"),
1037 },
1038 },
1039 {
1040 .ident = "Dell Studio XPS 8100",
1041 .matches = {
1042 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1043 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Studio XPS 8100"),
1044 },
1045 },
1046 {
1047 .ident = "Dell Inspiron 580",
1048 .matches = {
1049 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1050 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Inspiron 580 "),
1051 },
1052 },
1053 { }
1054 };
1055
1056 /*
1057 * On some machines all fan related SMM functions implemented by Dell BIOS
1058 * firmware freeze kernel for about 500ms. Until Dell fixes these problems fan
1059 * support for affected blacklisted Dell machines stay disabled.
1060 * See bug: https://bugzilla.kernel.org/show_bug.cgi?id=195751
1061 */
1062 static struct dmi_system_id i8k_blacklist_fan_support_dmi_table[] __initdata = {
1063 {
1064 .ident = "Dell Inspiron 7720",
1065 .matches = {
1066 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1067 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Inspiron 7720"),
1068 },
1069 },
1070 {
1071 .ident = "Dell Vostro 3360",
1072 .matches = {
1073 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1074 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Vostro 3360"),
1075 },
1076 },
1077 {
1078 .ident = "Dell XPS13 9333",
1079 .matches = {
1080 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1081 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "XPS13 9333"),
1082 },
1083 },
1084 { }
1085 };
1086
1087 /*
1088 * Probe for the presence of a supported laptop.
1089 */
i8k_probe(void)1090 static int __init i8k_probe(void)
1091 {
1092 const struct dmi_system_id *id;
1093 int fan, ret;
1094
1095 /*
1096 * Get DMI information
1097 */
1098 if (!dmi_check_system(i8k_dmi_table)) {
1099 if (!ignore_dmi && !force)
1100 return -ENODEV;
1101
1102 pr_info("not running on a supported Dell system.\n");
1103 pr_info("vendor=%s, model=%s, version=%s\n",
1104 i8k_get_dmi_data(DMI_SYS_VENDOR),
1105 i8k_get_dmi_data(DMI_PRODUCT_NAME),
1106 i8k_get_dmi_data(DMI_BIOS_VERSION));
1107 }
1108
1109 if (dmi_check_system(i8k_blacklist_fan_support_dmi_table)) {
1110 pr_warn("broken Dell BIOS detected, disallow fan support\n");
1111 if (!force)
1112 disallow_fan_support = true;
1113 }
1114
1115 if (dmi_check_system(i8k_blacklist_fan_type_dmi_table)) {
1116 pr_warn("broken Dell BIOS detected, disallow fan type call\n");
1117 if (!force)
1118 disallow_fan_type_call = true;
1119 }
1120
1121 strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION),
1122 sizeof(bios_version));
1123 strlcpy(bios_machineid, i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
1124 sizeof(bios_machineid));
1125
1126 /*
1127 * Get SMM Dell signature
1128 */
1129 if (i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG1) &&
1130 i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) {
1131 pr_err("unable to get SMM Dell signature\n");
1132 if (!force)
1133 return -ENODEV;
1134 }
1135
1136 /*
1137 * Set fan multiplier and maximal fan speed from dmi config
1138 * Values specified in module parameters override values from dmi
1139 */
1140 id = dmi_first_match(i8k_dmi_table);
1141 if (id && id->driver_data) {
1142 const struct i8k_config_data *conf = id->driver_data;
1143 if (!fan_mult && conf->fan_mult)
1144 fan_mult = conf->fan_mult;
1145 if (!fan_max && conf->fan_max)
1146 fan_max = conf->fan_max;
1147 }
1148
1149 i8k_fan_max = fan_max ? : I8K_FAN_HIGH; /* Must not be 0 */
1150 i8k_pwm_mult = DIV_ROUND_UP(255, i8k_fan_max);
1151
1152 if (!fan_mult) {
1153 /*
1154 * Autodetect fan multiplier based on nominal rpm
1155 * If fan reports rpm value too high then set multiplier to 1
1156 */
1157 for (fan = 0; fan < 2; ++fan) {
1158 ret = i8k_get_fan_nominal_speed(fan, i8k_fan_max);
1159 if (ret < 0)
1160 continue;
1161 if (ret > I8K_FAN_MAX_RPM)
1162 i8k_fan_mult = 1;
1163 break;
1164 }
1165 } else {
1166 /* Fan multiplier was specified in module param or in dmi */
1167 i8k_fan_mult = fan_mult;
1168 }
1169
1170 return 0;
1171 }
1172
i8k_init(void)1173 static int __init i8k_init(void)
1174 {
1175 int err;
1176
1177 /* Are we running on an supported laptop? */
1178 if (i8k_probe())
1179 return -ENODEV;
1180
1181 err = i8k_init_hwmon();
1182 if (err)
1183 return err;
1184
1185 i8k_init_procfs();
1186 return 0;
1187 }
1188
i8k_exit(void)1189 static void __exit i8k_exit(void)
1190 {
1191 hwmon_device_unregister(i8k_hwmon_dev);
1192 i8k_exit_procfs();
1193 }
1194
1195 module_init(i8k_init);
1196 module_exit(i8k_exit);
1197
