ACPI: EC: export ec_transaction() for msi-laptop driver
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / acpi / processor_perflib.c
blob7ba5e49ab302c523848930773d474c351fed30a1
1 /*
2 * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $)
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8 * - Added processor hotplug support
11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or (at
16 * your option) any later version.
18 * This program is distributed in the hope that it will be useful, but
19 * WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * General Public License for more details.
23 * You should have received a copy of the GNU General Public License along
24 * with this program; if not, write to the Free Software Foundation, Inc.,
25 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/cpufreq.h>
34 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
35 #include <linux/proc_fs.h>
36 #include <linux/seq_file.h>
37 #include <linux/mutex.h>
39 #include <asm/uaccess.h>
40 #endif
42 #include <acpi/acpi_bus.h>
43 #include <acpi/processor.h>
45 #define ACPI_PROCESSOR_COMPONENT 0x01000000
46 #define ACPI_PROCESSOR_CLASS "processor"
47 #define ACPI_PROCESSOR_DRIVER_NAME "ACPI Processor Driver"
48 #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance"
49 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
50 ACPI_MODULE_NAME("acpi_processor")
52 static DEFINE_MUTEX(performance_mutex);
55 * _PPC support is implemented as a CPUfreq policy notifier:
56 * This means each time a CPUfreq driver registered also with
57 * the ACPI core is asked to change the speed policy, the maximum
58 * value is adjusted so that it is within the platform limit.
60 * Also, when a new platform limit value is detected, the CPUfreq
61 * policy is adjusted accordingly.
64 #define PPC_REGISTERED 1
65 #define PPC_IN_USE 2
67 static int acpi_processor_ppc_status = 0;
69 static int acpi_processor_ppc_notifier(struct notifier_block *nb,
70 unsigned long event, void *data)
72 struct cpufreq_policy *policy = data;
73 struct acpi_processor *pr;
74 unsigned int ppc = 0;
76 mutex_lock(&performance_mutex);
78 if (event != CPUFREQ_INCOMPATIBLE)
79 goto out;
81 pr = processors[policy->cpu];
82 if (!pr || !pr->performance)
83 goto out;
85 ppc = (unsigned int)pr->performance_platform_limit;
86 if (!ppc)
87 goto out;
89 if (ppc > pr->performance->state_count)
90 goto out;
92 cpufreq_verify_within_limits(policy, 0,
93 pr->performance->states[ppc].
94 core_frequency * 1000);
96 out:
97 mutex_unlock(&performance_mutex);
99 return 0;
102 static struct notifier_block acpi_ppc_notifier_block = {
103 .notifier_call = acpi_processor_ppc_notifier,
106 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
108 acpi_status status = 0;
109 unsigned long ppc = 0;
112 if (!pr)
113 return -EINVAL;
116 * _PPC indicates the maximum state currently supported by the platform
117 * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
119 status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
121 if (status != AE_NOT_FOUND)
122 acpi_processor_ppc_status |= PPC_IN_USE;
124 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
125 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC"));
126 return -ENODEV;
129 pr->performance_platform_limit = (int)ppc;
131 return 0;
134 int acpi_processor_ppc_has_changed(struct acpi_processor *pr)
136 int ret = acpi_processor_get_platform_limit(pr);
137 if (ret < 0)
138 return (ret);
139 else
140 return cpufreq_update_policy(pr->id);
143 void acpi_processor_ppc_init(void)
145 if (!cpufreq_register_notifier
146 (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
147 acpi_processor_ppc_status |= PPC_REGISTERED;
148 else
149 printk(KERN_DEBUG
150 "Warning: Processor Platform Limit not supported.\n");
153 void acpi_processor_ppc_exit(void)
155 if (acpi_processor_ppc_status & PPC_REGISTERED)
156 cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
157 CPUFREQ_POLICY_NOTIFIER);
159 acpi_processor_ppc_status &= ~PPC_REGISTERED;
162 static int acpi_processor_get_performance_control(struct acpi_processor *pr)
164 int result = 0;
165 acpi_status status = 0;
166 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
167 union acpi_object *pct = NULL;
168 union acpi_object obj = { 0 };
171 status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
172 if (ACPI_FAILURE(status)) {
173 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT"));
174 return -ENODEV;
177 pct = (union acpi_object *)buffer.pointer;
178 if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
179 || (pct->package.count != 2)) {
180 printk(KERN_ERR PREFIX "Invalid _PCT data\n");
181 result = -EFAULT;
182 goto end;
186 * control_register
189 obj = pct->package.elements[0];
191 if ((obj.type != ACPI_TYPE_BUFFER)
192 || (obj.buffer.length < sizeof(struct acpi_pct_register))
193 || (obj.buffer.pointer == NULL)) {
194 printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n");
195 result = -EFAULT;
196 goto end;
198 memcpy(&pr->performance->control_register, obj.buffer.pointer,
199 sizeof(struct acpi_pct_register));
202 * status_register
205 obj = pct->package.elements[1];
207 if ((obj.type != ACPI_TYPE_BUFFER)
208 || (obj.buffer.length < sizeof(struct acpi_pct_register))
209 || (obj.buffer.pointer == NULL)) {
210 printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n");
211 result = -EFAULT;
212 goto end;
215 memcpy(&pr->performance->status_register, obj.buffer.pointer,
216 sizeof(struct acpi_pct_register));
218 end:
219 kfree(buffer.pointer);
221 return result;
224 static int acpi_processor_get_performance_states(struct acpi_processor *pr)
226 int result = 0;
227 acpi_status status = AE_OK;
228 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
229 struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" };
230 struct acpi_buffer state = { 0, NULL };
231 union acpi_object *pss = NULL;
232 int i;
235 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
236 if (ACPI_FAILURE(status)) {
237 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS"));
238 return -ENODEV;
241 pss = (union acpi_object *)buffer.pointer;
242 if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
243 printk(KERN_ERR PREFIX "Invalid _PSS data\n");
244 result = -EFAULT;
245 goto end;
248 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
249 pss->package.count));
251 pr->performance->state_count = pss->package.count;
252 pr->performance->states =
253 kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
254 GFP_KERNEL);
255 if (!pr->performance->states) {
256 result = -ENOMEM;
257 goto end;
260 for (i = 0; i < pr->performance->state_count; i++) {
262 struct acpi_processor_px *px = &(pr->performance->states[i]);
264 state.length = sizeof(struct acpi_processor_px);
265 state.pointer = px;
267 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
269 status = acpi_extract_package(&(pss->package.elements[i]),
270 &format, &state);
271 if (ACPI_FAILURE(status)) {
272 ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data"));
273 result = -EFAULT;
274 kfree(pr->performance->states);
275 goto end;
278 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
279 "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
281 (u32) px->core_frequency,
282 (u32) px->power,
283 (u32) px->transition_latency,
284 (u32) px->bus_master_latency,
285 (u32) px->control, (u32) px->status));
287 if (!px->core_frequency) {
288 printk(KERN_ERR PREFIX
289 "Invalid _PSS data: freq is zero\n");
290 result = -EFAULT;
291 kfree(pr->performance->states);
292 goto end;
296 end:
297 kfree(buffer.pointer);
299 return result;
302 static int acpi_processor_get_performance_info(struct acpi_processor *pr)
304 int result = 0;
305 acpi_status status = AE_OK;
306 acpi_handle handle = NULL;
309 if (!pr || !pr->performance || !pr->handle)
310 return -EINVAL;
312 status = acpi_get_handle(pr->handle, "_PCT", &handle);
313 if (ACPI_FAILURE(status)) {
314 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
315 "ACPI-based processor performance control unavailable\n"));
316 return -ENODEV;
319 result = acpi_processor_get_performance_control(pr);
320 if (result)
321 return result;
323 result = acpi_processor_get_performance_states(pr);
324 if (result)
325 return result;
327 result = acpi_processor_get_platform_limit(pr);
328 if (result)
329 return result;
331 return 0;
334 int acpi_processor_notify_smm(struct module *calling_module)
336 acpi_status status;
337 static int is_done = 0;
340 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
341 return -EBUSY;
343 if (!try_module_get(calling_module))
344 return -EINVAL;
346 /* is_done is set to negative if an error occured,
347 * and to postitive if _no_ error occured, but SMM
348 * was already notified. This avoids double notification
349 * which might lead to unexpected results...
351 if (is_done > 0) {
352 module_put(calling_module);
353 return 0;
354 } else if (is_done < 0) {
355 module_put(calling_module);
356 return is_done;
359 is_done = -EIO;
361 /* Can't write pstate_cnt to smi_cmd if either value is zero */
362 if ((!acpi_fadt.smi_cmd) || (!acpi_fadt.pstate_cnt)) {
363 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_cnt\n"));
364 module_put(calling_module);
365 return 0;
368 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
369 "Writing pstate_cnt [0x%x] to smi_cmd [0x%x]\n",
370 acpi_fadt.pstate_cnt, acpi_fadt.smi_cmd));
372 /* FADT v1 doesn't support pstate_cnt, many BIOS vendors use
373 * it anyway, so we need to support it... */
374 if (acpi_fadt_is_v1) {
375 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
376 "Using v1.0 FADT reserved value for pstate_cnt\n"));
379 status = acpi_os_write_port(acpi_fadt.smi_cmd,
380 (u32) acpi_fadt.pstate_cnt, 8);
381 if (ACPI_FAILURE(status)) {
382 ACPI_EXCEPTION((AE_INFO, status,
383 "Failed to write pstate_cnt [0x%x] to "
384 "smi_cmd [0x%x]", acpi_fadt.pstate_cnt,
385 acpi_fadt.smi_cmd));
386 module_put(calling_module);
387 return status;
390 /* Success. If there's no _PPC, we need to fear nothing, so
391 * we can allow the cpufreq driver to be rmmod'ed. */
392 is_done = 1;
394 if (!(acpi_processor_ppc_status & PPC_IN_USE))
395 module_put(calling_module);
397 return 0;
400 EXPORT_SYMBOL(acpi_processor_notify_smm);
402 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
403 /* /proc/acpi/processor/../performance interface (DEPRECATED) */
405 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file);
406 static struct file_operations acpi_processor_perf_fops = {
407 .open = acpi_processor_perf_open_fs,
408 .read = seq_read,
409 .llseek = seq_lseek,
410 .release = single_release,
413 static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset)
415 struct acpi_processor *pr = (struct acpi_processor *)seq->private;
416 int i;
419 if (!pr)
420 goto end;
422 if (!pr->performance) {
423 seq_puts(seq, "<not supported>\n");
424 goto end;
427 seq_printf(seq, "state count: %d\n"
428 "active state: P%d\n",
429 pr->performance->state_count, pr->performance->state);
431 seq_puts(seq, "states:\n");
432 for (i = 0; i < pr->performance->state_count; i++)
433 seq_printf(seq,
434 " %cP%d: %d MHz, %d mW, %d uS\n",
435 (i == pr->performance->state ? '*' : ' '), i,
436 (u32) pr->performance->states[i].core_frequency,
437 (u32) pr->performance->states[i].power,
438 (u32) pr->performance->states[i].transition_latency);
440 end:
441 return 0;
444 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file)
446 return single_open(file, acpi_processor_perf_seq_show,
447 PDE(inode)->data);
450 static ssize_t
451 acpi_processor_write_performance(struct file *file,
452 const char __user * buffer,
453 size_t count, loff_t * data)
455 int result = 0;
456 struct seq_file *m = (struct seq_file *)file->private_data;
457 struct acpi_processor *pr = (struct acpi_processor *)m->private;
458 struct acpi_processor_performance *perf;
459 char state_string[12] = { '\0' };
460 unsigned int new_state = 0;
461 struct cpufreq_policy policy;
464 if (!pr || (count > sizeof(state_string) - 1))
465 return -EINVAL;
467 perf = pr->performance;
468 if (!perf)
469 return -EINVAL;
471 if (copy_from_user(state_string, buffer, count))
472 return -EFAULT;
474 state_string[count] = '\0';
475 new_state = simple_strtoul(state_string, NULL, 0);
477 if (new_state >= perf->state_count)
478 return -EINVAL;
480 cpufreq_get_policy(&policy, pr->id);
482 policy.cpu = pr->id;
483 policy.min = perf->states[new_state].core_frequency * 1000;
484 policy.max = perf->states[new_state].core_frequency * 1000;
486 result = cpufreq_set_policy(&policy);
487 if (result)
488 return result;
490 return count;
493 static void acpi_cpufreq_add_file(struct acpi_processor *pr)
495 struct proc_dir_entry *entry = NULL;
496 struct acpi_device *device = NULL;
499 if (acpi_bus_get_device(pr->handle, &device))
500 return;
502 /* add file 'performance' [R/W] */
503 entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
504 S_IFREG | S_IRUGO | S_IWUSR,
505 acpi_device_dir(device));
506 if (entry){
507 acpi_processor_perf_fops.write = acpi_processor_write_performance;
508 entry->proc_fops = &acpi_processor_perf_fops;
509 entry->data = acpi_driver_data(device);
510 entry->owner = THIS_MODULE;
512 return;
515 static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
517 struct acpi_device *device = NULL;
520 if (acpi_bus_get_device(pr->handle, &device))
521 return;
523 /* remove file 'performance' */
524 remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
525 acpi_device_dir(device));
527 return;
530 #else
531 static void acpi_cpufreq_add_file(struct acpi_processor *pr)
533 return;
535 static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
537 return;
539 #endif /* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */
541 static int acpi_processor_get_psd(struct acpi_processor *pr)
543 int result = 0;
544 acpi_status status = AE_OK;
545 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
546 struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"};
547 struct acpi_buffer state = {0, NULL};
548 union acpi_object *psd = NULL;
549 struct acpi_psd_package *pdomain;
551 status = acpi_evaluate_object(pr->handle, "_PSD", NULL, &buffer);
552 if (ACPI_FAILURE(status)) {
553 return -ENODEV;
556 psd = (union acpi_object *) buffer.pointer;
557 if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) {
558 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
559 result = -EFAULT;
560 goto end;
563 if (psd->package.count != 1) {
564 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
565 result = -EFAULT;
566 goto end;
569 pdomain = &(pr->performance->domain_info);
571 state.length = sizeof(struct acpi_psd_package);
572 state.pointer = pdomain;
574 status = acpi_extract_package(&(psd->package.elements[0]),
575 &format, &state);
576 if (ACPI_FAILURE(status)) {
577 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
578 result = -EFAULT;
579 goto end;
582 if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) {
583 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:num_entries\n"));
584 result = -EFAULT;
585 goto end;
588 if (pdomain->revision != ACPI_PSD_REV0_REVISION) {
589 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:revision\n"));
590 result = -EFAULT;
591 goto end;
594 end:
595 kfree(buffer.pointer);
596 return result;
599 int acpi_processor_preregister_performance(
600 struct acpi_processor_performance **performance)
602 int count, count_target;
603 int retval = 0;
604 unsigned int i, j;
605 cpumask_t covered_cpus;
606 struct acpi_processor *pr;
607 struct acpi_psd_package *pdomain;
608 struct acpi_processor *match_pr;
609 struct acpi_psd_package *match_pdomain;
611 mutex_lock(&performance_mutex);
613 retval = 0;
615 /* Call _PSD for all CPUs */
616 for_each_possible_cpu(i) {
617 pr = processors[i];
618 if (!pr) {
619 /* Look only at processors in ACPI namespace */
620 continue;
623 if (pr->performance) {
624 retval = -EBUSY;
625 continue;
628 if (!performance || !performance[i]) {
629 retval = -EINVAL;
630 continue;
633 pr->performance = performance[i];
634 cpu_set(i, pr->performance->shared_cpu_map);
635 if (acpi_processor_get_psd(pr)) {
636 retval = -EINVAL;
637 continue;
640 if (retval)
641 goto err_ret;
644 * Now that we have _PSD data from all CPUs, lets setup P-state
645 * domain info.
647 for_each_possible_cpu(i) {
648 pr = processors[i];
649 if (!pr)
650 continue;
652 /* Basic validity check for domain info */
653 pdomain = &(pr->performance->domain_info);
654 if ((pdomain->revision != ACPI_PSD_REV0_REVISION) ||
655 (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES)) {
656 retval = -EINVAL;
657 goto err_ret;
659 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
660 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
661 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
662 retval = -EINVAL;
663 goto err_ret;
667 cpus_clear(covered_cpus);
668 for_each_possible_cpu(i) {
669 pr = processors[i];
670 if (!pr)
671 continue;
673 if (cpu_isset(i, covered_cpus))
674 continue;
676 pdomain = &(pr->performance->domain_info);
677 cpu_set(i, pr->performance->shared_cpu_map);
678 cpu_set(i, covered_cpus);
679 if (pdomain->num_processors <= 1)
680 continue;
682 /* Validate the Domain info */
683 count_target = pdomain->num_processors;
684 count = 1;
685 if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
686 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
687 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
688 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW;
689 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
690 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY;
692 for_each_possible_cpu(j) {
693 if (i == j)
694 continue;
696 match_pr = processors[j];
697 if (!match_pr)
698 continue;
700 match_pdomain = &(match_pr->performance->domain_info);
701 if (match_pdomain->domain != pdomain->domain)
702 continue;
704 /* Here i and j are in the same domain */
706 if (match_pdomain->num_processors != count_target) {
707 retval = -EINVAL;
708 goto err_ret;
711 if (pdomain->coord_type != match_pdomain->coord_type) {
712 retval = -EINVAL;
713 goto err_ret;
716 cpu_set(j, covered_cpus);
717 cpu_set(j, pr->performance->shared_cpu_map);
718 count++;
721 for_each_possible_cpu(j) {
722 if (i == j)
723 continue;
725 match_pr = processors[j];
726 if (!match_pr)
727 continue;
729 match_pdomain = &(match_pr->performance->domain_info);
730 if (match_pdomain->domain != pdomain->domain)
731 continue;
733 match_pr->performance->shared_type =
734 pr->performance->shared_type;
735 match_pr->performance->shared_cpu_map =
736 pr->performance->shared_cpu_map;
740 err_ret:
741 if (retval) {
742 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error while parsing _PSD domain information. Assuming no coordination\n"));
745 for_each_possible_cpu(i) {
746 pr = processors[i];
747 if (!pr || !pr->performance)
748 continue;
750 /* Assume no coordination on any error parsing domain info */
751 if (retval) {
752 cpus_clear(pr->performance->shared_cpu_map);
753 cpu_set(i, pr->performance->shared_cpu_map);
754 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
756 pr->performance = NULL; /* Will be set for real in register */
759 mutex_unlock(&performance_mutex);
760 return retval;
762 EXPORT_SYMBOL(acpi_processor_preregister_performance);
766 acpi_processor_register_performance(struct acpi_processor_performance
767 *performance, unsigned int cpu)
769 struct acpi_processor *pr;
772 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
773 return -EINVAL;
775 mutex_lock(&performance_mutex);
777 pr = processors[cpu];
778 if (!pr) {
779 mutex_unlock(&performance_mutex);
780 return -ENODEV;
783 if (pr->performance) {
784 mutex_unlock(&performance_mutex);
785 return -EBUSY;
788 WARN_ON(!performance);
790 pr->performance = performance;
792 if (acpi_processor_get_performance_info(pr)) {
793 pr->performance = NULL;
794 mutex_unlock(&performance_mutex);
795 return -EIO;
798 acpi_cpufreq_add_file(pr);
800 mutex_unlock(&performance_mutex);
801 return 0;
804 EXPORT_SYMBOL(acpi_processor_register_performance);
806 void
807 acpi_processor_unregister_performance(struct acpi_processor_performance
808 *performance, unsigned int cpu)
810 struct acpi_processor *pr;
813 mutex_lock(&performance_mutex);
815 pr = processors[cpu];
816 if (!pr) {
817 mutex_unlock(&performance_mutex);
818 return;
821 if (pr->performance)
822 kfree(pr->performance->states);
823 pr->performance = NULL;
825 acpi_cpufreq_remove_file(pr);
827 mutex_unlock(&performance_mutex);
829 return;
832 EXPORT_SYMBOL(acpi_processor_unregister_performance);