xref: /openbmc/linux/drivers/hwmon/dell-smm-hwmon.c (revision 1ac731c529cd4d6adbce134754b51ff7d822b145)
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/capability.h>
16  #include <linux/cpu.h>
17  #include <linux/ctype.h>
18  #include <linux/delay.h>
19  #include <linux/dmi.h>
20  #include <linux/err.h>
21  #include <linux/errno.h>
22  #include <linux/hwmon.h>
23  #include <linux/init.h>
24  #include <linux/kconfig.h>
25  #include <linux/kernel.h>
26  #include <linux/module.h>
27  #include <linux/mutex.h>
28  #include <linux/platform_device.h>
29  #include <linux/proc_fs.h>
30  #include <linux/seq_file.h>
31  #include <linux/slab.h>
32  #include <linux/smp.h>
33  #include <linux/string.h>
34  #include <linux/thermal.h>
35  #include <linux/types.h>
36  #include <linux/uaccess.h>
37  
38  #include <linux/i8k.h>
39  
40  #define I8K_SMM_FN_STATUS	0x0025
41  #define I8K_SMM_POWER_STATUS	0x0069
42  #define I8K_SMM_SET_FAN		0x01a3
43  #define I8K_SMM_GET_FAN		0x00a3
44  #define I8K_SMM_GET_SPEED	0x02a3
45  #define I8K_SMM_GET_FAN_TYPE	0x03a3
46  #define I8K_SMM_GET_NOM_SPEED	0x04a3
47  #define I8K_SMM_GET_TEMP	0x10a3
48  #define I8K_SMM_GET_TEMP_TYPE	0x11a3
49  #define I8K_SMM_GET_DELL_SIG1	0xfea3
50  #define I8K_SMM_GET_DELL_SIG2	0xffa3
51  
52  /* in usecs */
53  #define DELL_SMM_MAX_DURATION  250000
54  
55  #define I8K_FAN_MULT		30
56  #define I8K_FAN_RPM_THRESHOLD	1000
57  #define I8K_MAX_TEMP		127
58  
59  #define I8K_FN_NONE		0x00
60  #define I8K_FN_UP		0x01
61  #define I8K_FN_DOWN		0x02
62  #define I8K_FN_MUTE		0x04
63  #define I8K_FN_MASK		0x07
64  #define I8K_FN_SHIFT		8
65  
66  #define I8K_POWER_AC		0x05
67  #define I8K_POWER_BATTERY	0x01
68  
69  #define DELL_SMM_NO_TEMP	10
70  #define DELL_SMM_NO_FANS	3
71  
72  struct dell_smm_data {
73  	struct mutex i8k_mutex; /* lock for sensors writes */
74  	char bios_version[4];
75  	char bios_machineid[16];
76  	uint i8k_fan_mult;
77  	uint i8k_pwm_mult;
78  	uint i8k_fan_max;
79  	bool disallow_fan_type_call;
80  	bool disallow_fan_support;
81  	unsigned int manual_fan;
82  	unsigned int auto_fan;
83  	int temp_type[DELL_SMM_NO_TEMP];
84  	bool fan[DELL_SMM_NO_FANS];
85  	int fan_type[DELL_SMM_NO_FANS];
86  	int *fan_nominal_speed[DELL_SMM_NO_FANS];
87  };
88  
89  struct dell_smm_cooling_data {
90  	u8 fan_num;
91  	struct dell_smm_data *data;
92  };
93  
94  MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
95  MODULE_AUTHOR("Pali Rohár <pali@kernel.org>");
96  MODULE_DESCRIPTION("Dell laptop SMM BIOS hwmon driver");
97  MODULE_LICENSE("GPL");
98  MODULE_ALIAS("i8k");
99  
100  static bool force;
101  module_param_unsafe(force, bool, 0);
102  MODULE_PARM_DESC(force, "Force loading without checking for supported models and features");
103  
104  static bool ignore_dmi;
105  module_param(ignore_dmi, bool, 0);
106  MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
107  
108  #if IS_ENABLED(CONFIG_I8K)
109  static bool restricted = true;
110  module_param(restricted, bool, 0);
111  MODULE_PARM_DESC(restricted, "Restrict fan control and serial number to CAP_SYS_ADMIN (default: 1)");
112  
113  static bool power_status;
114  module_param(power_status, bool, 0600);
115  MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k (default: 0)");
116  #endif
117  
118  static uint fan_mult;
119  module_param(fan_mult, uint, 0);
120  MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with (default: autodetect)");
121  
122  static uint fan_max;
123  module_param(fan_max, uint, 0);
124  MODULE_PARM_DESC(fan_max, "Maximum configurable fan speed (default: autodetect)");
125  
126  struct smm_regs {
127  	unsigned int eax;
128  	unsigned int ebx;
129  	unsigned int ecx;
130  	unsigned int edx;
131  	unsigned int esi;
132  	unsigned int edi;
133  };
134  
135  static const char * const temp_labels[] = {
136  	"CPU",
137  	"GPU",
138  	"SODIMM",
139  	"Other",
140  	"Ambient",
141  	"Other",
142  };
143  
144  static const char * const fan_labels[] = {
145  	"Processor Fan",
146  	"Motherboard Fan",
147  	"Video Fan",
148  	"Power Supply Fan",
149  	"Chipset Fan",
150  	"Other Fan",
151  };
152  
153  static const char * const docking_labels[] = {
154  	"Docking Processor Fan",
155  	"Docking Motherboard Fan",
156  	"Docking Video Fan",
157  	"Docking Power Supply Fan",
158  	"Docking Chipset Fan",
159  	"Docking Other Fan",
160  };
161  
i8k_get_dmi_data(int field)162  static inline const char __init *i8k_get_dmi_data(int field)
163  {
164  	const char *dmi_data = dmi_get_system_info(field);
165  
166  	return dmi_data && *dmi_data ? dmi_data : "?";
167  }
168  
169  /*
170   * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard.
171   */
i8k_smm_func(void * par)172  static int i8k_smm_func(void *par)
173  {
174  	ktime_t calltime = ktime_get();
175  	struct smm_regs *regs = par;
176  	int eax = regs->eax;
177  	int ebx = regs->ebx;
178  	unsigned char carry;
179  	long long duration;
180  
181  	/* SMM requires CPU 0 */
182  	if (smp_processor_id() != 0)
183  		return -EBUSY;
184  
185  	asm volatile("out %%al,$0xb2\n\t"
186  		     "out %%al,$0x84\n\t"
187  		     "setc %0\n"
188  		     : "=mr" (carry),
189  		       "+a" (regs->eax),
190  		       "+b" (regs->ebx),
191  		       "+c" (regs->ecx),
192  		       "+d" (regs->edx),
193  		       "+S" (regs->esi),
194  		       "+D" (regs->edi));
195  
196  	duration = ktime_us_delta(ktime_get(), calltime);
197  	pr_debug("smm(0x%.4x 0x%.4x) = 0x%.4x carry: %d (took %7lld usecs)\n",
198  		 eax, ebx, regs->eax & 0xffff, carry, duration);
199  
200  	if (duration > DELL_SMM_MAX_DURATION)
201  		pr_warn_once("SMM call took %lld usecs!\n", duration);
202  
203  	if (carry || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
204  		return -EINVAL;
205  
206  	return 0;
207  }
208  
209  /*
210   * Call the System Management Mode BIOS.
211   */
i8k_smm(struct smm_regs * regs)212  static int i8k_smm(struct smm_regs *regs)
213  {
214  	int ret;
215  
216  	cpus_read_lock();
217  	ret = smp_call_on_cpu(0, i8k_smm_func, regs, true);
218  	cpus_read_unlock();
219  
220  	return ret;
221  }
222  
223  /*
224   * Read the fan status.
225   */
i8k_get_fan_status(const struct dell_smm_data * data,u8 fan)226  static int i8k_get_fan_status(const struct dell_smm_data *data, u8 fan)
227  {
228  	struct smm_regs regs = {
229  		.eax = I8K_SMM_GET_FAN,
230  		.ebx = fan,
231  	};
232  
233  	if (data->disallow_fan_support)
234  		return -EINVAL;
235  
236  	return i8k_smm(&regs) ? : regs.eax & 0xff;
237  }
238  
239  /*
240   * Read the fan speed in RPM.
241   */
i8k_get_fan_speed(const struct dell_smm_data * data,u8 fan)242  static int i8k_get_fan_speed(const struct dell_smm_data *data, u8 fan)
243  {
244  	struct smm_regs regs = {
245  		.eax = I8K_SMM_GET_SPEED,
246  		.ebx = fan,
247  	};
248  
249  	if (data->disallow_fan_support)
250  		return -EINVAL;
251  
252  	return i8k_smm(&regs) ? : (regs.eax & 0xffff) * data->i8k_fan_mult;
253  }
254  
255  /*
256   * Read the fan type.
257   */
_i8k_get_fan_type(const struct dell_smm_data * data,u8 fan)258  static int _i8k_get_fan_type(const struct dell_smm_data *data, u8 fan)
259  {
260  	struct smm_regs regs = {
261  		.eax = I8K_SMM_GET_FAN_TYPE,
262  		.ebx = fan,
263  	};
264  
265  	if (data->disallow_fan_support || data->disallow_fan_type_call)
266  		return -EINVAL;
267  
268  	return i8k_smm(&regs) ? : regs.eax & 0xff;
269  }
270  
i8k_get_fan_type(struct dell_smm_data * data,u8 fan)271  static int i8k_get_fan_type(struct dell_smm_data *data, u8 fan)
272  {
273  	/* I8K_SMM_GET_FAN_TYPE SMM call is expensive, so cache values */
274  	if (data->fan_type[fan] == INT_MIN)
275  		data->fan_type[fan] = _i8k_get_fan_type(data, fan);
276  
277  	return data->fan_type[fan];
278  }
279  
280  /*
281   * Read the fan nominal rpm for specific fan speed.
282   */
i8k_get_fan_nominal_speed(const struct dell_smm_data * data,u8 fan,int speed)283  static int __init i8k_get_fan_nominal_speed(const struct dell_smm_data *data, u8 fan, int speed)
284  {
285  	struct smm_regs regs = {
286  		.eax = I8K_SMM_GET_NOM_SPEED,
287  		.ebx = fan | (speed << 8),
288  	};
289  
290  	if (data->disallow_fan_support)
291  		return -EINVAL;
292  
293  	return i8k_smm(&regs) ? : (regs.eax & 0xffff);
294  }
295  
296  /*
297   * Enable or disable automatic BIOS fan control support
298   */
i8k_enable_fan_auto_mode(const struct dell_smm_data * data,bool enable)299  static int i8k_enable_fan_auto_mode(const struct dell_smm_data *data, bool enable)
300  {
301  	struct smm_regs regs = { };
302  
303  	if (data->disallow_fan_support)
304  		return -EINVAL;
305  
306  	regs.eax = enable ? data->auto_fan : data->manual_fan;
307  	return i8k_smm(&regs);
308  }
309  
310  /*
311   * Set the fan speed (off, low, high, ...).
312   */
i8k_set_fan(const struct dell_smm_data * data,u8 fan,int speed)313  static int i8k_set_fan(const struct dell_smm_data *data, u8 fan, int speed)
314  {
315  	struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
316  
317  	if (data->disallow_fan_support)
318  		return -EINVAL;
319  
320  	speed = (speed < 0) ? 0 : ((speed > data->i8k_fan_max) ? data->i8k_fan_max : speed);
321  	regs.ebx = fan | (speed << 8);
322  
323  	return i8k_smm(&regs);
324  }
325  
i8k_get_temp_type(u8 sensor)326  static int __init i8k_get_temp_type(u8 sensor)
327  {
328  	struct smm_regs regs = {
329  		.eax = I8K_SMM_GET_TEMP_TYPE,
330  		.ebx = sensor,
331  	};
332  
333  	return i8k_smm(&regs) ? : regs.eax & 0xff;
334  }
335  
336  /*
337   * Read the cpu temperature.
338   */
_i8k_get_temp(u8 sensor)339  static int _i8k_get_temp(u8 sensor)
340  {
341  	struct smm_regs regs = {
342  		.eax = I8K_SMM_GET_TEMP,
343  		.ebx = sensor,
344  	};
345  
346  	return i8k_smm(&regs) ? : regs.eax & 0xff;
347  }
348  
i8k_get_temp(u8 sensor)349  static int i8k_get_temp(u8 sensor)
350  {
351  	int temp = _i8k_get_temp(sensor);
352  
353  	/*
354  	 * Sometimes the temperature sensor returns 0x99, which is out of range.
355  	 * In this case we retry (once) before returning an error.
356  	 # 1003655137 00000058 00005a4b
357  	 # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
358  	 # 1003655139 00000054 00005c52
359  	 */
360  	if (temp == 0x99) {
361  		msleep(100);
362  		temp = _i8k_get_temp(sensor);
363  	}
364  	/*
365  	 * Return -ENODATA for all invalid temperatures.
366  	 *
367  	 * Known instances are the 0x99 value as seen above as well as
368  	 * 0xc1 (193), which may be returned when trying to read the GPU
369  	 * temperature if the system supports a GPU and it is currently
370  	 * turned off.
371  	 */
372  	if (temp > I8K_MAX_TEMP)
373  		return -ENODATA;
374  
375  	return temp;
376  }
377  
i8k_get_dell_signature(int req_fn)378  static int __init i8k_get_dell_signature(int req_fn)
379  {
380  	struct smm_regs regs = { .eax = req_fn, };
381  	int rc;
382  
383  	rc = i8k_smm(&regs);
384  	if (rc < 0)
385  		return rc;
386  
387  	return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
388  }
389  
390  #if IS_ENABLED(CONFIG_I8K)
391  
392  /*
393   * Read the Fn key status.
394   */
i8k_get_fn_status(void)395  static int i8k_get_fn_status(void)
396  {
397  	struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, };
398  	int rc;
399  
400  	rc = i8k_smm(&regs);
401  	if (rc < 0)
402  		return rc;
403  
404  	switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) {
405  	case I8K_FN_UP:
406  		return I8K_VOL_UP;
407  	case I8K_FN_DOWN:
408  		return I8K_VOL_DOWN;
409  	case I8K_FN_MUTE:
410  		return I8K_VOL_MUTE;
411  	default:
412  		return 0;
413  	}
414  }
415  
416  /*
417   * Read the power status.
418   */
i8k_get_power_status(void)419  static int i8k_get_power_status(void)
420  {
421  	struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, };
422  	int rc;
423  
424  	rc = i8k_smm(&regs);
425  	if (rc < 0)
426  		return rc;
427  
428  	return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY;
429  }
430  
431  /*
432   * Procfs interface
433   */
434  
i8k_ioctl(struct file * fp,unsigned int cmd,unsigned long arg)435  static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
436  {
437  	struct dell_smm_data *data = pde_data(file_inode(fp));
438  	int __user *argp = (int __user *)arg;
439  	int speed, err;
440  	int val = 0;
441  
442  	if (!argp)
443  		return -EINVAL;
444  
445  	switch (cmd) {
446  	case I8K_BIOS_VERSION:
447  		if (!isdigit(data->bios_version[0]) || !isdigit(data->bios_version[1]) ||
448  		    !isdigit(data->bios_version[2]))
449  			return -EINVAL;
450  
451  		val = (data->bios_version[0] << 16) |
452  				(data->bios_version[1] << 8) | data->bios_version[2];
453  
454  		if (copy_to_user(argp, &val, sizeof(val)))
455  			return -EFAULT;
456  
457  		return 0;
458  	case I8K_MACHINE_ID:
459  		if (restricted && !capable(CAP_SYS_ADMIN))
460  			return -EPERM;
461  
462  		if (copy_to_user(argp, data->bios_machineid, sizeof(data->bios_machineid)))
463  			return -EFAULT;
464  
465  		return 0;
466  	case I8K_FN_STATUS:
467  		val = i8k_get_fn_status();
468  		break;
469  
470  	case I8K_POWER_STATUS:
471  		val = i8k_get_power_status();
472  		break;
473  
474  	case I8K_GET_TEMP:
475  		val = i8k_get_temp(0);
476  		break;
477  
478  	case I8K_GET_SPEED:
479  		if (copy_from_user(&val, argp, sizeof(int)))
480  			return -EFAULT;
481  
482  		if (val > U8_MAX || val < 0)
483  			return -EINVAL;
484  
485  		val = i8k_get_fan_speed(data, val);
486  		break;
487  
488  	case I8K_GET_FAN:
489  		if (copy_from_user(&val, argp, sizeof(int)))
490  			return -EFAULT;
491  
492  		if (val > U8_MAX || val < 0)
493  			return -EINVAL;
494  
495  		val = i8k_get_fan_status(data, val);
496  		break;
497  
498  	case I8K_SET_FAN:
499  		if (restricted && !capable(CAP_SYS_ADMIN))
500  			return -EPERM;
501  
502  		if (copy_from_user(&val, argp, sizeof(int)))
503  			return -EFAULT;
504  
505  		if (val > U8_MAX || val < 0)
506  			return -EINVAL;
507  
508  		if (copy_from_user(&speed, argp + 1, sizeof(int)))
509  			return -EFAULT;
510  
511  		mutex_lock(&data->i8k_mutex);
512  		err = i8k_set_fan(data, val, speed);
513  		if (err < 0)
514  			val = err;
515  		else
516  			val = i8k_get_fan_status(data, val);
517  		mutex_unlock(&data->i8k_mutex);
518  		break;
519  
520  	default:
521  		return -ENOIOCTLCMD;
522  	}
523  
524  	if (val < 0)
525  		return val;
526  
527  	if (copy_to_user(argp, &val, sizeof(int)))
528  		return -EFAULT;
529  
530  	return 0;
531  }
532  
533  /*
534   * Print the information for /proc/i8k.
535   */
i8k_proc_show(struct seq_file * seq,void * offset)536  static int i8k_proc_show(struct seq_file *seq, void *offset)
537  {
538  	struct dell_smm_data *data = seq->private;
539  	int fn_key, cpu_temp, ac_power;
540  	int left_fan, right_fan, left_speed, right_speed;
541  
542  	cpu_temp	= i8k_get_temp(0);				/* 11100 µs */
543  	left_fan	= i8k_get_fan_status(data, I8K_FAN_LEFT);	/*   580 µs */
544  	right_fan	= i8k_get_fan_status(data, I8K_FAN_RIGHT);	/*   580 µs */
545  	left_speed	= i8k_get_fan_speed(data, I8K_FAN_LEFT);	/*   580 µs */
546  	right_speed	= i8k_get_fan_speed(data, I8K_FAN_RIGHT);	/*   580 µs */
547  	fn_key		= i8k_get_fn_status();				/*   750 µs */
548  	if (power_status)
549  		ac_power = i8k_get_power_status();			/* 14700 µs */
550  	else
551  		ac_power = -1;
552  
553  	/*
554  	 * Info:
555  	 *
556  	 * 1)  Format version (this will change if format changes)
557  	 * 2)  BIOS version
558  	 * 3)  BIOS machine ID
559  	 * 4)  Cpu temperature
560  	 * 5)  Left fan status
561  	 * 6)  Right fan status
562  	 * 7)  Left fan speed
563  	 * 8)  Right fan speed
564  	 * 9)  AC power
565  	 * 10) Fn Key status
566  	 */
567  	seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
568  		   I8K_PROC_FMT,
569  		   data->bios_version,
570  		   (restricted && !capable(CAP_SYS_ADMIN)) ? "-1" : data->bios_machineid,
571  		   cpu_temp,
572  		   left_fan, right_fan, left_speed, right_speed,
573  		   ac_power, fn_key);
574  
575  	return 0;
576  }
577  
i8k_open_fs(struct inode * inode,struct file * file)578  static int i8k_open_fs(struct inode *inode, struct file *file)
579  {
580  	return single_open(file, i8k_proc_show, pde_data(inode));
581  }
582  
583  static const struct proc_ops i8k_proc_ops = {
584  	.proc_open	= i8k_open_fs,
585  	.proc_read	= seq_read,
586  	.proc_lseek	= seq_lseek,
587  	.proc_release	= single_release,
588  	.proc_ioctl	= i8k_ioctl,
589  };
590  
i8k_exit_procfs(void * param)591  static void i8k_exit_procfs(void *param)
592  {
593  	remove_proc_entry("i8k", NULL);
594  }
595  
i8k_init_procfs(struct device * dev)596  static void __init i8k_init_procfs(struct device *dev)
597  {
598  	struct dell_smm_data *data = dev_get_drvdata(dev);
599  
600  	/* Only register exit function if creation was successful */
601  	if (proc_create_data("i8k", 0, NULL, &i8k_proc_ops, data))
602  		devm_add_action_or_reset(dev, i8k_exit_procfs, NULL);
603  }
604  
605  #else
606  
i8k_init_procfs(struct device * dev)607  static void __init i8k_init_procfs(struct device *dev)
608  {
609  }
610  
611  #endif
612  
dell_smm_get_max_state(struct thermal_cooling_device * dev,unsigned long * state)613  static int dell_smm_get_max_state(struct thermal_cooling_device *dev, unsigned long *state)
614  {
615  	struct dell_smm_cooling_data *cdata = dev->devdata;
616  
617  	*state = cdata->data->i8k_fan_max;
618  
619  	return 0;
620  }
621  
dell_smm_get_cur_state(struct thermal_cooling_device * dev,unsigned long * state)622  static int dell_smm_get_cur_state(struct thermal_cooling_device *dev, unsigned long *state)
623  {
624  	struct dell_smm_cooling_data *cdata = dev->devdata;
625  	int ret;
626  
627  	ret = i8k_get_fan_status(cdata->data, cdata->fan_num);
628  	if (ret < 0)
629  		return ret;
630  
631  	*state = ret;
632  
633  	return 0;
634  }
635  
dell_smm_set_cur_state(struct thermal_cooling_device * dev,unsigned long state)636  static int dell_smm_set_cur_state(struct thermal_cooling_device *dev, unsigned long state)
637  {
638  	struct dell_smm_cooling_data *cdata = dev->devdata;
639  	struct dell_smm_data *data = cdata->data;
640  	int ret;
641  
642  	if (state > data->i8k_fan_max)
643  		return -EINVAL;
644  
645  	mutex_lock(&data->i8k_mutex);
646  	ret = i8k_set_fan(data, cdata->fan_num, (int)state);
647  	mutex_unlock(&data->i8k_mutex);
648  
649  	return ret;
650  }
651  
652  static const struct thermal_cooling_device_ops dell_smm_cooling_ops = {
653  	.get_max_state = dell_smm_get_max_state,
654  	.get_cur_state = dell_smm_get_cur_state,
655  	.set_cur_state = dell_smm_set_cur_state,
656  };
657  
dell_smm_is_visible(const void * drvdata,enum hwmon_sensor_types type,u32 attr,int channel)658  static umode_t dell_smm_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
659  				   int channel)
660  {
661  	const struct dell_smm_data *data = drvdata;
662  
663  	switch (type) {
664  	case hwmon_temp:
665  		switch (attr) {
666  		case hwmon_temp_input:
667  			/* _i8k_get_temp() is fine since we do not care about the actual value */
668  			if (data->temp_type[channel] >= 0 || _i8k_get_temp(channel) >= 0)
669  				return 0444;
670  
671  			break;
672  		case hwmon_temp_label:
673  			if (data->temp_type[channel] >= 0)
674  				return 0444;
675  
676  			break;
677  		default:
678  			break;
679  		}
680  		break;
681  	case hwmon_fan:
682  		if (data->disallow_fan_support)
683  			break;
684  
685  		switch (attr) {
686  		case hwmon_fan_input:
687  			if (data->fan[channel])
688  				return 0444;
689  
690  			break;
691  		case hwmon_fan_label:
692  			if (data->fan[channel] && !data->disallow_fan_type_call)
693  				return 0444;
694  
695  			break;
696  		case hwmon_fan_min:
697  		case hwmon_fan_max:
698  		case hwmon_fan_target:
699  			if (data->fan_nominal_speed[channel])
700  				return 0444;
701  
702  			break;
703  		default:
704  			break;
705  		}
706  		break;
707  	case hwmon_pwm:
708  		if (data->disallow_fan_support)
709  			break;
710  
711  		switch (attr) {
712  		case hwmon_pwm_input:
713  			if (data->fan[channel])
714  				return 0644;
715  
716  			break;
717  		case hwmon_pwm_enable:
718  			if (data->auto_fan)
719  				/*
720  				 * There is no command for retrieve the current status
721  				 * from BIOS, and userspace/firmware itself can change
722  				 * it.
723  				 * Thus we can only provide write-only access for now.
724  				 */
725  				return 0200;
726  
727  			break;
728  		default:
729  			break;
730  		}
731  		break;
732  	default:
733  		break;
734  	}
735  
736  	return 0;
737  }
738  
dell_smm_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)739  static int dell_smm_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
740  			 long *val)
741  {
742  	struct dell_smm_data *data = dev_get_drvdata(dev);
743  	int mult = data->i8k_fan_mult;
744  	int ret;
745  
746  	switch (type) {
747  	case hwmon_temp:
748  		switch (attr) {
749  		case hwmon_temp_input:
750  			ret = i8k_get_temp(channel);
751  			if (ret < 0)
752  				return ret;
753  
754  			*val = ret * 1000;
755  
756  			return 0;
757  		default:
758  			break;
759  		}
760  		break;
761  	case hwmon_fan:
762  		switch (attr) {
763  		case hwmon_fan_input:
764  			ret = i8k_get_fan_speed(data, channel);
765  			if (ret < 0)
766  				return ret;
767  
768  			*val = ret;
769  
770  			return 0;
771  		case hwmon_fan_min:
772  			*val = data->fan_nominal_speed[channel][0] * mult;
773  
774  			return 0;
775  		case hwmon_fan_max:
776  			*val = data->fan_nominal_speed[channel][data->i8k_fan_max] * mult;
777  
778  			return 0;
779  		case hwmon_fan_target:
780  			ret = i8k_get_fan_status(data, channel);
781  			if (ret < 0)
782  				return ret;
783  
784  			if (ret > data->i8k_fan_max)
785  				ret = data->i8k_fan_max;
786  
787  			*val = data->fan_nominal_speed[channel][ret] * mult;
788  
789  			return 0;
790  		default:
791  			break;
792  		}
793  		break;
794  	case hwmon_pwm:
795  		switch (attr) {
796  		case hwmon_pwm_input:
797  			ret = i8k_get_fan_status(data, channel);
798  			if (ret < 0)
799  				return ret;
800  
801  			*val = clamp_val(ret * data->i8k_pwm_mult, 0, 255);
802  
803  			return 0;
804  		default:
805  			break;
806  		}
807  		break;
808  	default:
809  		break;
810  	}
811  
812  	return -EOPNOTSUPP;
813  }
814  
dell_smm_fan_label(struct dell_smm_data * data,int channel)815  static const char *dell_smm_fan_label(struct dell_smm_data *data, int channel)
816  {
817  	bool dock = false;
818  	int type = i8k_get_fan_type(data, channel);
819  
820  	if (type < 0)
821  		return ERR_PTR(type);
822  
823  	if (type & 0x10) {
824  		dock = true;
825  		type &= 0x0F;
826  	}
827  
828  	if (type >= ARRAY_SIZE(fan_labels))
829  		type = ARRAY_SIZE(fan_labels) - 1;
830  
831  	return dock ? docking_labels[type] : fan_labels[type];
832  }
833  
dell_smm_read_string(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,const char ** str)834  static int dell_smm_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr,
835  				int channel, const char **str)
836  {
837  	struct dell_smm_data *data = dev_get_drvdata(dev);
838  
839  	switch (type) {
840  	case hwmon_temp:
841  		switch (attr) {
842  		case hwmon_temp_label:
843  			*str = temp_labels[data->temp_type[channel]];
844  			return 0;
845  		default:
846  			break;
847  		}
848  		break;
849  	case hwmon_fan:
850  		switch (attr) {
851  		case hwmon_fan_label:
852  			*str = dell_smm_fan_label(data, channel);
853  			return PTR_ERR_OR_ZERO(*str);
854  		default:
855  			break;
856  		}
857  		break;
858  	default:
859  		break;
860  	}
861  
862  	return -EOPNOTSUPP;
863  }
864  
dell_smm_write(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long val)865  static int dell_smm_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
866  			  long val)
867  {
868  	struct dell_smm_data *data = dev_get_drvdata(dev);
869  	unsigned long pwm;
870  	bool enable;
871  	int err;
872  
873  	switch (type) {
874  	case hwmon_pwm:
875  		switch (attr) {
876  		case hwmon_pwm_input:
877  			pwm = clamp_val(DIV_ROUND_CLOSEST(val, data->i8k_pwm_mult), 0,
878  					data->i8k_fan_max);
879  
880  			mutex_lock(&data->i8k_mutex);
881  			err = i8k_set_fan(data, channel, pwm);
882  			mutex_unlock(&data->i8k_mutex);
883  
884  			if (err < 0)
885  				return err;
886  
887  			return 0;
888  		case hwmon_pwm_enable:
889  			if (!val)
890  				return -EINVAL;
891  
892  			if (val == 1)
893  				enable = false;
894  			else
895  				enable = true;
896  
897  			mutex_lock(&data->i8k_mutex);
898  			err = i8k_enable_fan_auto_mode(data, enable);
899  			mutex_unlock(&data->i8k_mutex);
900  
901  			if (err < 0)
902  				return err;
903  
904  			return 0;
905  		default:
906  			break;
907  		}
908  		break;
909  	default:
910  		break;
911  	}
912  
913  	return -EOPNOTSUPP;
914  }
915  
916  static const struct hwmon_ops dell_smm_ops = {
917  	.is_visible = dell_smm_is_visible,
918  	.read = dell_smm_read,
919  	.read_string = dell_smm_read_string,
920  	.write = dell_smm_write,
921  };
922  
923  static const struct hwmon_channel_info * const dell_smm_info[] = {
924  	HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
925  	HWMON_CHANNEL_INFO(temp,
926  			   HWMON_T_INPUT | HWMON_T_LABEL,
927  			   HWMON_T_INPUT | HWMON_T_LABEL,
928  			   HWMON_T_INPUT | HWMON_T_LABEL,
929  			   HWMON_T_INPUT | HWMON_T_LABEL,
930  			   HWMON_T_INPUT | HWMON_T_LABEL,
931  			   HWMON_T_INPUT | HWMON_T_LABEL,
932  			   HWMON_T_INPUT | HWMON_T_LABEL,
933  			   HWMON_T_INPUT | HWMON_T_LABEL,
934  			   HWMON_T_INPUT | HWMON_T_LABEL,
935  			   HWMON_T_INPUT | HWMON_T_LABEL
936  			   ),
937  	HWMON_CHANNEL_INFO(fan,
938  			   HWMON_F_INPUT | HWMON_F_LABEL | HWMON_F_MIN | HWMON_F_MAX |
939  			   HWMON_F_TARGET,
940  			   HWMON_F_INPUT | HWMON_F_LABEL | HWMON_F_MIN | HWMON_F_MAX |
941  			   HWMON_F_TARGET,
942  			   HWMON_F_INPUT | HWMON_F_LABEL | HWMON_F_MIN | HWMON_F_MAX |
943  			   HWMON_F_TARGET
944  			   ),
945  	HWMON_CHANNEL_INFO(pwm,
946  			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
947  			   HWMON_PWM_INPUT,
948  			   HWMON_PWM_INPUT
949  			   ),
950  	NULL
951  };
952  
953  static const struct hwmon_chip_info dell_smm_chip_info = {
954  	.ops = &dell_smm_ops,
955  	.info = dell_smm_info,
956  };
957  
dell_smm_init_cdev(struct device * dev,u8 fan_num)958  static int __init dell_smm_init_cdev(struct device *dev, u8 fan_num)
959  {
960  	struct dell_smm_data *data = dev_get_drvdata(dev);
961  	struct thermal_cooling_device *cdev;
962  	struct dell_smm_cooling_data *cdata;
963  	int ret = 0;
964  	char *name;
965  
966  	name = kasprintf(GFP_KERNEL, "dell-smm-fan%u", fan_num + 1);
967  	if (!name)
968  		return -ENOMEM;
969  
970  	cdata = devm_kmalloc(dev, sizeof(*cdata), GFP_KERNEL);
971  	if (cdata) {
972  		cdata->fan_num = fan_num;
973  		cdata->data = data;
974  		cdev = devm_thermal_of_cooling_device_register(dev, NULL, name, cdata,
975  							       &dell_smm_cooling_ops);
976  		if (IS_ERR(cdev)) {
977  			devm_kfree(dev, cdata);
978  			ret = PTR_ERR(cdev);
979  		}
980  	} else {
981  		ret = -ENOMEM;
982  	}
983  
984  	kfree(name);
985  
986  	return ret;
987  }
988  
dell_smm_init_hwmon(struct device * dev)989  static int __init dell_smm_init_hwmon(struct device *dev)
990  {
991  	struct dell_smm_data *data = dev_get_drvdata(dev);
992  	struct device *dell_smm_hwmon_dev;
993  	int state, err;
994  	u8 i;
995  
996  	for (i = 0; i < DELL_SMM_NO_TEMP; i++) {
997  		data->temp_type[i] = i8k_get_temp_type(i);
998  		if (data->temp_type[i] < 0)
999  			continue;
1000  
1001  		if (data->temp_type[i] >= ARRAY_SIZE(temp_labels))
1002  			data->temp_type[i] = ARRAY_SIZE(temp_labels) - 1;
1003  	}
1004  
1005  	for (i = 0; i < DELL_SMM_NO_FANS; i++) {
1006  		data->fan_type[i] = INT_MIN;
1007  		err = i8k_get_fan_status(data, i);
1008  		if (err < 0)
1009  			err = i8k_get_fan_type(data, i);
1010  
1011  		if (err < 0)
1012  			continue;
1013  
1014  		data->fan[i] = true;
1015  
1016  		/* the cooling device is not critical, ignore failures */
1017  		if (IS_REACHABLE(CONFIG_THERMAL)) {
1018  			err = dell_smm_init_cdev(dev, i);
1019  			if (err < 0)
1020  				dev_warn(dev, "Failed to register cooling device for fan %u\n",
1021  					 i + 1);
1022  		}
1023  
1024  		data->fan_nominal_speed[i] = devm_kmalloc_array(dev, data->i8k_fan_max + 1,
1025  								sizeof(*data->fan_nominal_speed[i]),
1026  								GFP_KERNEL);
1027  		if (!data->fan_nominal_speed[i])
1028  			continue;
1029  
1030  		for (state = 0; state <= data->i8k_fan_max; state++) {
1031  			err = i8k_get_fan_nominal_speed(data, i, state);
1032  			if (err < 0) {
1033  				/* Mark nominal speed table as invalid in case of error */
1034  				devm_kfree(dev, data->fan_nominal_speed[i]);
1035  				data->fan_nominal_speed[i] = NULL;
1036  				break;
1037  			}
1038  			data->fan_nominal_speed[i][state] = err;
1039  			/*
1040  			 * Autodetect fan multiplier based on nominal rpm if multiplier
1041  			 * was not specified as module param or in DMI. If fan reports
1042  			 * rpm value too high then set multiplier to 1.
1043  			 */
1044  			if (!fan_mult && err > I8K_FAN_RPM_THRESHOLD)
1045  				data->i8k_fan_mult = 1;
1046  		}
1047  	}
1048  
1049  	dell_smm_hwmon_dev = devm_hwmon_device_register_with_info(dev, "dell_smm", data,
1050  								  &dell_smm_chip_info, NULL);
1051  
1052  	return PTR_ERR_OR_ZERO(dell_smm_hwmon_dev);
1053  }
1054  
1055  struct i8k_config_data {
1056  	uint fan_mult;
1057  	uint fan_max;
1058  };
1059  
1060  enum i8k_configs {
1061  	DELL_LATITUDE_D520,
1062  	DELL_PRECISION_490,
1063  	DELL_STUDIO,
1064  	DELL_XPS,
1065  };
1066  
1067  /*
1068   * Only use for machines which need some special configuration
1069   * in order to work correctly (e.g. if autoconfig fails on this machines).
1070   */
1071  
1072  static const struct i8k_config_data i8k_config_data[] __initconst = {
1073  	[DELL_LATITUDE_D520] = {
1074  		.fan_mult = 1,
1075  		.fan_max = I8K_FAN_TURBO,
1076  	},
1077  	[DELL_PRECISION_490] = {
1078  		.fan_mult = 1,
1079  		.fan_max = I8K_FAN_TURBO,
1080  	},
1081  	[DELL_STUDIO] = {
1082  		.fan_mult = 1,
1083  		.fan_max = I8K_FAN_HIGH,
1084  	},
1085  	[DELL_XPS] = {
1086  		.fan_mult = 1,
1087  		.fan_max = I8K_FAN_HIGH,
1088  	},
1089  };
1090  
1091  static const struct dmi_system_id i8k_dmi_table[] __initconst = {
1092  	{
1093  		.ident = "Dell G5 5590",
1094  		.matches = {
1095  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1096  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "G5 5590"),
1097  		},
1098  	},
1099  	{
1100  		.ident = "Dell Inspiron",
1101  		.matches = {
1102  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
1103  			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
1104  		},
1105  	},
1106  	{
1107  		.ident = "Dell Latitude",
1108  		.matches = {
1109  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
1110  			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
1111  		},
1112  	},
1113  	{
1114  		.ident = "Dell Inspiron 2",
1115  		.matches = {
1116  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1117  			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
1118  		},
1119  	},
1120  	{
1121  		.ident = "Dell Latitude D520",
1122  		.matches = {
1123  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1124  			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude D520"),
1125  		},
1126  		.driver_data = (void *)&i8k_config_data[DELL_LATITUDE_D520],
1127  	},
1128  	{
1129  		.ident = "Dell Latitude 2",
1130  		.matches = {
1131  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1132  			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
1133  		},
1134  	},
1135  	{	/* UK Inspiron 6400  */
1136  		.ident = "Dell Inspiron 3",
1137  		.matches = {
1138  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1139  			DMI_MATCH(DMI_PRODUCT_NAME, "MM061"),
1140  		},
1141  	},
1142  	{
1143  		.ident = "Dell Inspiron 3",
1144  		.matches = {
1145  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1146  			DMI_MATCH(DMI_PRODUCT_NAME, "MP061"),
1147  		},
1148  	},
1149  	{
1150  		.ident = "Dell Precision 490",
1151  		.matches = {
1152  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1153  			DMI_MATCH(DMI_PRODUCT_NAME,
1154  				  "Precision WorkStation 490"),
1155  		},
1156  		.driver_data = (void *)&i8k_config_data[DELL_PRECISION_490],
1157  	},
1158  	{
1159  		.ident = "Dell Precision",
1160  		.matches = {
1161  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1162  			DMI_MATCH(DMI_PRODUCT_NAME, "Precision"),
1163  		},
1164  	},
1165  	{
1166  		.ident = "Dell Vostro",
1167  		.matches = {
1168  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1169  			DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
1170  		},
1171  	},
1172  	{
1173  		.ident = "Dell Studio",
1174  		.matches = {
1175  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1176  			DMI_MATCH(DMI_PRODUCT_NAME, "Studio"),
1177  		},
1178  		.driver_data = (void *)&i8k_config_data[DELL_STUDIO],
1179  	},
1180  	{
1181  		.ident = "Dell XPS M140",
1182  		.matches = {
1183  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1184  			DMI_MATCH(DMI_PRODUCT_NAME, "MXC051"),
1185  		},
1186  		.driver_data = (void *)&i8k_config_data[DELL_XPS],
1187  	},
1188  	{
1189  		.ident = "Dell XPS",
1190  		.matches = {
1191  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1192  			DMI_MATCH(DMI_PRODUCT_NAME, "XPS"),
1193  		},
1194  	},
1195  	{ }
1196  };
1197  
1198  MODULE_DEVICE_TABLE(dmi, i8k_dmi_table);
1199  
1200  /*
1201   * On some machines once I8K_SMM_GET_FAN_TYPE is issued then CPU fan speed
1202   * randomly going up and down due to bug in Dell SMM or BIOS. Here is blacklist
1203   * of affected Dell machines for which we disallow I8K_SMM_GET_FAN_TYPE call.
1204   * See bug: https://bugzilla.kernel.org/show_bug.cgi?id=100121
1205   */
1206  static const struct dmi_system_id i8k_blacklist_fan_type_dmi_table[] __initconst = {
1207  	{
1208  		.ident = "Dell Studio XPS 8000",
1209  		.matches = {
1210  			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1211  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Studio XPS 8000"),
1212  		},
1213  	},
1214  	{
1215  		.ident = "Dell Studio XPS 8100",
1216  		.matches = {
1217  			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1218  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Studio XPS 8100"),
1219  		},
1220  	},
1221  	{
1222  		.ident = "Dell Inspiron 580",
1223  		.matches = {
1224  			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1225  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Inspiron 580 "),
1226  		},
1227  	},
1228  	{
1229  		.ident = "Dell Inspiron 3505",
1230  		.matches = {
1231  			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1232  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Inspiron 3505"),
1233  		},
1234  	},
1235  	{ }
1236  };
1237  
1238  /*
1239   * On some machines all fan related SMM functions implemented by Dell BIOS
1240   * firmware freeze kernel for about 500ms. Until Dell fixes these problems fan
1241   * support for affected blacklisted Dell machines stay disabled.
1242   * See bug: https://bugzilla.kernel.org/show_bug.cgi?id=195751
1243   */
1244  static const struct dmi_system_id i8k_blacklist_fan_support_dmi_table[] __initconst = {
1245  	{
1246  		.ident = "Dell Inspiron 7720",
1247  		.matches = {
1248  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1249  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Inspiron 7720"),
1250  		},
1251  	},
1252  	{
1253  		.ident = "Dell Vostro 3360",
1254  		.matches = {
1255  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1256  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Vostro 3360"),
1257  		},
1258  	},
1259  	{
1260  		.ident = "Dell XPS13 9333",
1261  		.matches = {
1262  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1263  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "XPS13 9333"),
1264  		},
1265  	},
1266  	{
1267  		.ident = "Dell XPS 15 L502X",
1268  		.matches = {
1269  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1270  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L502X"),
1271  		},
1272  	},
1273  	{ }
1274  };
1275  
1276  struct i8k_fan_control_data {
1277  	unsigned int manual_fan;
1278  	unsigned int auto_fan;
1279  };
1280  
1281  enum i8k_fan_controls {
1282  	I8K_FAN_34A3_35A3,
1283  };
1284  
1285  static const struct i8k_fan_control_data i8k_fan_control_data[] __initconst = {
1286  	[I8K_FAN_34A3_35A3] = {
1287  		.manual_fan = 0x34a3,
1288  		.auto_fan = 0x35a3,
1289  	},
1290  };
1291  
1292  static const struct dmi_system_id i8k_whitelist_fan_control[] __initconst = {
1293  	{
1294  		.ident = "Dell Latitude 5480",
1295  		.matches = {
1296  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1297  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude 5480"),
1298  		},
1299  		.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
1300  	},
1301  	{
1302  		.ident = "Dell Latitude E6440",
1303  		.matches = {
1304  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1305  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude E6440"),
1306  		},
1307  		.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
1308  	},
1309  	{
1310  		.ident = "Dell Latitude E7440",
1311  		.matches = {
1312  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1313  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude E7440"),
1314  		},
1315  		.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
1316  	},
1317  	{
1318  		.ident = "Dell Precision 5530",
1319  		.matches = {
1320  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1321  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Precision 5530"),
1322  		},
1323  		.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
1324  	},
1325  	{
1326  		.ident = "Dell Precision 7510",
1327  		.matches = {
1328  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1329  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Precision 7510"),
1330  		},
1331  		.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
1332  	},
1333  	{
1334  		.ident = "Dell XPS 13 7390",
1335  		.matches = {
1336  			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
1337  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "XPS 13 7390"),
1338  		},
1339  		.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
1340  	},
1341  	{ }
1342  };
1343  
dell_smm_probe(struct platform_device * pdev)1344  static int __init dell_smm_probe(struct platform_device *pdev)
1345  {
1346  	struct dell_smm_data *data;
1347  	const struct dmi_system_id *id, *fan_control;
1348  	int ret;
1349  
1350  	data = devm_kzalloc(&pdev->dev, sizeof(struct dell_smm_data), GFP_KERNEL);
1351  	if (!data)
1352  		return -ENOMEM;
1353  
1354  	mutex_init(&data->i8k_mutex);
1355  	platform_set_drvdata(pdev, data);
1356  
1357  	if (dmi_check_system(i8k_blacklist_fan_support_dmi_table)) {
1358  		if (!force) {
1359  			dev_notice(&pdev->dev, "Disabling fan support due to BIOS bugs\n");
1360  			data->disallow_fan_support = true;
1361  		} else {
1362  			dev_warn(&pdev->dev, "Enabling fan support despite BIOS bugs\n");
1363  		}
1364  	}
1365  
1366  	if (dmi_check_system(i8k_blacklist_fan_type_dmi_table)) {
1367  		if (!force) {
1368  			dev_notice(&pdev->dev, "Disabling fan type call due to BIOS bugs\n");
1369  			data->disallow_fan_type_call = true;
1370  		} else {
1371  			dev_warn(&pdev->dev, "Enabling fan type call despite BIOS bugs\n");
1372  		}
1373  	}
1374  
1375  	strscpy(data->bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION),
1376  		sizeof(data->bios_version));
1377  	strscpy(data->bios_machineid, i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
1378  		sizeof(data->bios_machineid));
1379  
1380  	/*
1381  	 * Set fan multiplier and maximal fan speed from dmi config
1382  	 * Values specified in module parameters override values from dmi
1383  	 */
1384  	id = dmi_first_match(i8k_dmi_table);
1385  	if (id && id->driver_data) {
1386  		const struct i8k_config_data *conf = id->driver_data;
1387  
1388  		if (!fan_mult && conf->fan_mult)
1389  			fan_mult = conf->fan_mult;
1390  
1391  		if (!fan_max && conf->fan_max)
1392  			fan_max = conf->fan_max;
1393  	}
1394  
1395  	/* All options must not be 0 */
1396  	data->i8k_fan_mult = fan_mult ? : I8K_FAN_MULT;
1397  	data->i8k_fan_max = fan_max ? : I8K_FAN_HIGH;
1398  	data->i8k_pwm_mult = DIV_ROUND_UP(255, data->i8k_fan_max);
1399  
1400  	fan_control = dmi_first_match(i8k_whitelist_fan_control);
1401  	if (fan_control && fan_control->driver_data) {
1402  		const struct i8k_fan_control_data *control = fan_control->driver_data;
1403  
1404  		data->manual_fan = control->manual_fan;
1405  		data->auto_fan = control->auto_fan;
1406  		dev_info(&pdev->dev, "enabling support for setting automatic/manual fan control\n");
1407  	}
1408  
1409  	ret = dell_smm_init_hwmon(&pdev->dev);
1410  	if (ret)
1411  		return ret;
1412  
1413  	i8k_init_procfs(&pdev->dev);
1414  
1415  	return 0;
1416  }
1417  
1418  static struct platform_driver dell_smm_driver = {
1419  	.driver		= {
1420  		.name	= KBUILD_MODNAME,
1421  	},
1422  };
1423  
1424  static struct platform_device *dell_smm_device;
1425  
1426  /*
1427   * Probe for the presence of a supported laptop.
1428   */
i8k_init(void)1429  static int __init i8k_init(void)
1430  {
1431  	/*
1432  	 * Get DMI information
1433  	 */
1434  	if (!dmi_check_system(i8k_dmi_table)) {
1435  		if (!ignore_dmi && !force)
1436  			return -ENODEV;
1437  
1438  		pr_info("not running on a supported Dell system.\n");
1439  		pr_info("vendor=%s, model=%s, version=%s\n",
1440  			i8k_get_dmi_data(DMI_SYS_VENDOR),
1441  			i8k_get_dmi_data(DMI_PRODUCT_NAME),
1442  			i8k_get_dmi_data(DMI_BIOS_VERSION));
1443  	}
1444  
1445  	/*
1446  	 * Get SMM Dell signature
1447  	 */
1448  	if (i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG1) &&
1449  	    i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) {
1450  		if (!force)
1451  			return -ENODEV;
1452  
1453  		pr_err("Unable to get Dell SMM signature\n");
1454  	}
1455  
1456  	dell_smm_device = platform_create_bundle(&dell_smm_driver, dell_smm_probe, NULL, 0, NULL,
1457  						 0);
1458  
1459  	return PTR_ERR_OR_ZERO(dell_smm_device);
1460  }
1461  
i8k_exit(void)1462  static void __exit i8k_exit(void)
1463  {
1464  	platform_device_unregister(dell_smm_device);
1465  	platform_driver_unregister(&dell_smm_driver);
1466  }
1467  
1468  module_init(i8k_init);
1469  module_exit(i8k_exit);
1470