blob: b1eb376fae459fd5e28ed3dfd94de137f4857e49 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * processor_thermal.c - Passive cooling submodule of the ACPI processor driver
3 *
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
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or (at
15 * your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 * General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License along
23 * with this program; if not, write to the Free Software Foundation, Inc.,
24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25 *
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27 */
28
29#include <linux/kernel.h>
30#include <linux/module.h>
31#include <linux/init.h>
32#include <linux/cpufreq.h>
33#include <linux/proc_fs.h>
34#include <linux/seq_file.h>
Zhang Ruid9460fd22008-01-17 15:51:23 +080035#include <linux/sysdev.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036
37#include <asm/uaccess.h>
38
39#include <acpi/acpi_bus.h>
40#include <acpi/processor.h>
41#include <acpi/acpi_drivers.h>
42
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#define ACPI_PROCESSOR_CLASS "processor"
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#define _COMPONENT ACPI_PROCESSOR_COMPONENT
Len Brownf52fd662007-02-12 22:42:12 -050045ACPI_MODULE_NAME("processor_thermal");
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
47/* --------------------------------------------------------------------------
48 Limit Interface
49 -------------------------------------------------------------------------- */
Len Brown4be44fc2005-08-05 00:44:28 -040050static int acpi_processor_apply_limit(struct acpi_processor *pr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070051{
Len Brown4be44fc2005-08-05 00:44:28 -040052 int result = 0;
53 u16 px = 0;
54 u16 tx = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070055
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
57 if (!pr)
Patrick Mocheld550d982006-06-27 00:41:40 -040058 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -070059
60 if (!pr->flags.limit)
Patrick Mocheld550d982006-06-27 00:41:40 -040061 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -070062
63 if (pr->flags.throttling) {
64 if (pr->limit.user.tx > tx)
65 tx = pr->limit.user.tx;
66 if (pr->limit.thermal.tx > tx)
67 tx = pr->limit.thermal.tx;
68
69 result = acpi_processor_set_throttling(pr, tx);
70 if (result)
71 goto end;
72 }
73
74 pr->limit.state.px = px;
75 pr->limit.state.tx = tx;
76
Len Brown4be44fc2005-08-05 00:44:28 -040077 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
78 "Processor [%d] limit set to (P%d:T%d)\n", pr->id,
79 pr->limit.state.px, pr->limit.state.tx));
Linus Torvalds1da177e2005-04-16 15:20:36 -070080
Len Brown4be44fc2005-08-05 00:44:28 -040081 end:
Linus Torvalds1da177e2005-04-16 15:20:36 -070082 if (result)
Len Brown64684632006-06-26 23:41:38 -040083 printk(KERN_ERR PREFIX "Unable to set limit\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -070084
Patrick Mocheld550d982006-06-27 00:41:40 -040085 return result;
Linus Torvalds1da177e2005-04-16 15:20:36 -070086}
87
Linus Torvalds1da177e2005-04-16 15:20:36 -070088#ifdef CONFIG_CPU_FREQ
89
90/* If a passive cooling situation is detected, primarily CPUfreq is used, as it
91 * offers (in most cases) voltage scaling in addition to frequency scaling, and
92 * thus a cubic (instead of linear) reduction of energy. Also, we allow for
93 * _any_ cpufreq driver and not only the acpi-cpufreq driver.
94 */
95
Zhang Ruid9460fd22008-01-17 15:51:23 +080096#define CPUFREQ_THERMAL_MIN_STEP 0
97#define CPUFREQ_THERMAL_MAX_STEP 3
98
Mike Travisc938ac22008-03-05 08:31:29 -080099static DEFINE_PER_CPU(unsigned int, cpufreq_thermal_reduction_pctg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100static unsigned int acpi_thermal_cpufreq_is_init = 0;
101
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102static int cpu_has_cpufreq(unsigned int cpu)
103{
104 struct cpufreq_policy policy;
Thomas Renninger1cbf4c52004-09-16 11:07:00 -0400105 if (!acpi_thermal_cpufreq_is_init || cpufreq_get_policy(&policy, cpu))
Thomas Renninger75b245b32005-12-21 01:29:00 -0500106 return 0;
107 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108}
109
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110static int acpi_thermal_cpufreq_increase(unsigned int cpu)
111{
112 if (!cpu_has_cpufreq(cpu))
113 return -ENODEV;
114
Mike Travisc938ac22008-03-05 08:31:29 -0800115 if (per_cpu(cpufreq_thermal_reduction_pctg, cpu) <
Zhang Ruid9460fd22008-01-17 15:51:23 +0800116 CPUFREQ_THERMAL_MAX_STEP) {
Mike Travisc938ac22008-03-05 08:31:29 -0800117 per_cpu(cpufreq_thermal_reduction_pctg, cpu)++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 cpufreq_update_policy(cpu);
119 return 0;
120 }
121
122 return -ERANGE;
123}
124
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125static int acpi_thermal_cpufreq_decrease(unsigned int cpu)
126{
127 if (!cpu_has_cpufreq(cpu))
128 return -ENODEV;
129
Mike Travisc938ac22008-03-05 08:31:29 -0800130 if (per_cpu(cpufreq_thermal_reduction_pctg, cpu) >
Zhang Ruid9460fd22008-01-17 15:51:23 +0800131 (CPUFREQ_THERMAL_MIN_STEP + 1))
Mike Travisc938ac22008-03-05 08:31:29 -0800132 per_cpu(cpufreq_thermal_reduction_pctg, cpu)--;
Thomas Renninger1cbf4c52004-09-16 11:07:00 -0400133 else
Mike Travisc938ac22008-03-05 08:31:29 -0800134 per_cpu(cpufreq_thermal_reduction_pctg, cpu) = 0;
Thomas Renninger1cbf4c52004-09-16 11:07:00 -0400135 cpufreq_update_policy(cpu);
136 /* We reached max freq again and can leave passive mode */
Mike Travisc938ac22008-03-05 08:31:29 -0800137 return !per_cpu(cpufreq_thermal_reduction_pctg, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138}
139
Len Brown4be44fc2005-08-05 00:44:28 -0400140static int acpi_thermal_cpufreq_notifier(struct notifier_block *nb,
141 unsigned long event, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142{
143 struct cpufreq_policy *policy = data;
144 unsigned long max_freq = 0;
145
146 if (event != CPUFREQ_ADJUST)
147 goto out;
148
Mike Travisc938ac22008-03-05 08:31:29 -0800149 max_freq = (
150 policy->cpuinfo.max_freq *
151 (100 - per_cpu(cpufreq_thermal_reduction_pctg, policy->cpu) * 20)
152 ) / 100;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153
154 cpufreq_verify_within_limits(policy, 0, max_freq);
155
Len Brown4be44fc2005-08-05 00:44:28 -0400156 out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 return 0;
158}
159
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160static struct notifier_block acpi_thermal_cpufreq_notifier_block = {
161 .notifier_call = acpi_thermal_cpufreq_notifier,
162};
163
Zhang Ruid9460fd22008-01-17 15:51:23 +0800164static int cpufreq_get_max_state(unsigned int cpu)
165{
166 if (!cpu_has_cpufreq(cpu))
167 return 0;
168
169 return CPUFREQ_THERMAL_MAX_STEP;
170}
171
172static int cpufreq_get_cur_state(unsigned int cpu)
173{
174 if (!cpu_has_cpufreq(cpu))
175 return 0;
176
Mike Travisc938ac22008-03-05 08:31:29 -0800177 return per_cpu(cpufreq_thermal_reduction_pctg, cpu);
Zhang Ruid9460fd22008-01-17 15:51:23 +0800178}
179
180static int cpufreq_set_cur_state(unsigned int cpu, int state)
181{
182 if (!cpu_has_cpufreq(cpu))
183 return 0;
184
Mike Travisc938ac22008-03-05 08:31:29 -0800185 per_cpu(cpufreq_thermal_reduction_pctg, cpu) = state;
Zhang Ruid9460fd22008-01-17 15:51:23 +0800186 cpufreq_update_policy(cpu);
187 return 0;
188}
189
Len Brown4be44fc2005-08-05 00:44:28 -0400190void acpi_thermal_cpufreq_init(void)
191{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192 int i;
193
Mike Travisc938ac22008-03-05 08:31:29 -0800194 for (i = 0; i < nr_cpu_ids; i++)
195 if (cpu_present(i))
196 per_cpu(cpufreq_thermal_reduction_pctg, i) = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197
Len Brown4be44fc2005-08-05 00:44:28 -0400198 i = cpufreq_register_notifier(&acpi_thermal_cpufreq_notifier_block,
199 CPUFREQ_POLICY_NOTIFIER);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200 if (!i)
201 acpi_thermal_cpufreq_is_init = 1;
202}
203
Len Brown4be44fc2005-08-05 00:44:28 -0400204void acpi_thermal_cpufreq_exit(void)
205{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206 if (acpi_thermal_cpufreq_is_init)
Len Brown4be44fc2005-08-05 00:44:28 -0400207 cpufreq_unregister_notifier
208 (&acpi_thermal_cpufreq_notifier_block,
209 CPUFREQ_POLICY_NOTIFIER);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210
211 acpi_thermal_cpufreq_is_init = 0;
212}
213
Len Brown4be44fc2005-08-05 00:44:28 -0400214#else /* ! CONFIG_CPU_FREQ */
Zhang Ruid9460fd22008-01-17 15:51:23 +0800215static int cpufreq_get_max_state(unsigned int cpu)
216{
217 return 0;
218}
219
220static int cpufreq_get_cur_state(unsigned int cpu)
221{
222 return 0;
223}
224
225static int cpufreq_set_cur_state(unsigned int cpu, int state)
226{
227 return 0;
228}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229
Len Brown4be44fc2005-08-05 00:44:28 -0400230static int acpi_thermal_cpufreq_increase(unsigned int cpu)
231{
232 return -ENODEV;
233}
234static int acpi_thermal_cpufreq_decrease(unsigned int cpu)
235{
236 return -ENODEV;
237}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238
239#endif
240
Len Brown4be44fc2005-08-05 00:44:28 -0400241int acpi_processor_set_thermal_limit(acpi_handle handle, int type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242{
Len Brown4be44fc2005-08-05 00:44:28 -0400243 int result = 0;
244 struct acpi_processor *pr = NULL;
245 struct acpi_device *device = NULL;
Thomas Renninger1cbf4c52004-09-16 11:07:00 -0400246 int tx = 0, max_tx_px = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248
249 if ((type < ACPI_PROCESSOR_LIMIT_NONE)
Len Brown4be44fc2005-08-05 00:44:28 -0400250 || (type > ACPI_PROCESSOR_LIMIT_DECREMENT))
Patrick Mocheld550d982006-06-27 00:41:40 -0400251 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252
253 result = acpi_bus_get_device(handle, &device);
254 if (result)
Patrick Mocheld550d982006-06-27 00:41:40 -0400255 return result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256
Jan Engelhardt50dd0962006-10-01 00:28:50 +0200257 pr = acpi_driver_data(device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 if (!pr)
Patrick Mocheld550d982006-06-27 00:41:40 -0400259 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260
261 /* Thermal limits are always relative to the current Px/Tx state. */
262 if (pr->flags.throttling)
263 pr->limit.thermal.tx = pr->throttling.state;
264
265 /*
266 * Our default policy is to only use throttling at the lowest
267 * performance state.
268 */
269
270 tx = pr->limit.thermal.tx;
271
272 switch (type) {
273
274 case ACPI_PROCESSOR_LIMIT_NONE:
275 do {
276 result = acpi_thermal_cpufreq_decrease(pr->id);
277 } while (!result);
278 tx = 0;
279 break;
280
281 case ACPI_PROCESSOR_LIMIT_INCREMENT:
282 /* if going up: P-states first, T-states later */
283
284 result = acpi_thermal_cpufreq_increase(pr->id);
285 if (!result)
286 goto end;
287 else if (result == -ERANGE)
288 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
Len Brown4be44fc2005-08-05 00:44:28 -0400289 "At maximum performance state\n"));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290
291 if (pr->flags.throttling) {
292 if (tx == (pr->throttling.state_count - 1))
293 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
Len Brown4be44fc2005-08-05 00:44:28 -0400294 "At maximum throttling state\n"));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 else
296 tx++;
297 }
298 break;
299
300 case ACPI_PROCESSOR_LIMIT_DECREMENT:
301 /* if going down: T-states first, P-states later */
302
303 if (pr->flags.throttling) {
Thomas Renninger1cbf4c52004-09-16 11:07:00 -0400304 if (tx == 0) {
305 max_tx_px = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
Len Brown4be44fc2005-08-05 00:44:28 -0400307 "At minimum throttling state\n"));
Thomas Renninger1cbf4c52004-09-16 11:07:00 -0400308 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 tx--;
310 goto end;
311 }
312 }
313
314 result = acpi_thermal_cpufreq_decrease(pr->id);
Thomas Renninger1cbf4c52004-09-16 11:07:00 -0400315 if (result) {
316 /*
317 * We only could get -ERANGE, 1 or 0.
318 * In the first two cases we reached max freq again.
319 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
Len Brown4be44fc2005-08-05 00:44:28 -0400321 "At minimum performance state\n"));
Thomas Renninger1cbf4c52004-09-16 11:07:00 -0400322 max_tx_px = 1;
323 } else
324 max_tx_px = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325
326 break;
327 }
328
Len Brown4be44fc2005-08-05 00:44:28 -0400329 end:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330 if (pr->flags.throttling) {
331 pr->limit.thermal.px = 0;
332 pr->limit.thermal.tx = tx;
333
334 result = acpi_processor_apply_limit(pr);
335 if (result)
Len Brown64684632006-06-26 23:41:38 -0400336 printk(KERN_ERR PREFIX "Unable to set thermal limit\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337
338 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Thermal limit now (P%d:T%d)\n",
Len Brown4be44fc2005-08-05 00:44:28 -0400339 pr->limit.thermal.px, pr->limit.thermal.tx));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 } else
341 result = 0;
Thomas Renninger1cbf4c52004-09-16 11:07:00 -0400342 if (max_tx_px)
Patrick Mocheld550d982006-06-27 00:41:40 -0400343 return 1;
Thomas Renninger1cbf4c52004-09-16 11:07:00 -0400344 else
Patrick Mocheld550d982006-06-27 00:41:40 -0400345 return result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346}
347
Len Brown4be44fc2005-08-05 00:44:28 -0400348int acpi_processor_get_limit_info(struct acpi_processor *pr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350
351 if (!pr)
Patrick Mocheld550d982006-06-27 00:41:40 -0400352 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353
354 if (pr->flags.throttling)
355 pr->flags.limit = 1;
356
Patrick Mocheld550d982006-06-27 00:41:40 -0400357 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358}
359
Zhang Ruid9460fd22008-01-17 15:51:23 +0800360/* thermal coolign device callbacks */
361static int acpi_processor_max_state(struct acpi_processor *pr)
362{
363 int max_state = 0;
364
365 /*
366 * There exists four states according to
367 * cpufreq_thermal_reduction_ptg. 0, 1, 2, 3
368 */
369 max_state += cpufreq_get_max_state(pr->id);
370 if (pr->flags.throttling)
371 max_state += (pr->throttling.state_count -1);
372
373 return max_state;
374}
375static int
376processor_get_max_state(struct thermal_cooling_device *cdev, char *buf)
377{
378 struct acpi_device *device = cdev->devdata;
379 struct acpi_processor *pr = acpi_driver_data(device);
380
381 if (!device || !pr)
382 return -EINVAL;
383
384 return sprintf(buf, "%d\n", acpi_processor_max_state(pr));
385}
386
387static int
388processor_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
389{
390 struct acpi_device *device = cdev->devdata;
391 struct acpi_processor *pr = acpi_driver_data(device);
392 int cur_state;
393
394 if (!device || !pr)
395 return -EINVAL;
396
397 cur_state = cpufreq_get_cur_state(pr->id);
398 if (pr->flags.throttling)
399 cur_state += pr->throttling.state;
400
401 return sprintf(buf, "%d\n", cur_state);
402}
403
404static int
405processor_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
406{
407 struct acpi_device *device = cdev->devdata;
408 struct acpi_processor *pr = acpi_driver_data(device);
409 int result = 0;
410 int max_pstate;
411
412 if (!device || !pr)
413 return -EINVAL;
414
415 max_pstate = cpufreq_get_max_state(pr->id);
416
417 if (state > acpi_processor_max_state(pr))
418 return -EINVAL;
419
420 if (state <= max_pstate) {
421 if (pr->flags.throttling && pr->throttling.state)
422 result = acpi_processor_set_throttling(pr, 0);
423 cpufreq_set_cur_state(pr->id, state);
424 } else {
425 cpufreq_set_cur_state(pr->id, max_pstate);
426 result = acpi_processor_set_throttling(pr,
427 state - max_pstate);
428 }
429 return result;
430}
431
432struct thermal_cooling_device_ops processor_cooling_ops = {
433 .get_max_state = processor_get_max_state,
434 .get_cur_state = processor_get_cur_state,
435 .set_cur_state = processor_set_cur_state,
436};
437
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438/* /proc interface */
439
440static int acpi_processor_limit_seq_show(struct seq_file *seq, void *offset)
441{
Len Brown4be44fc2005-08-05 00:44:28 -0400442 struct acpi_processor *pr = (struct acpi_processor *)seq->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444
445 if (!pr)
446 goto end;
447
448 if (!pr->flags.limit) {
449 seq_puts(seq, "<not supported>\n");
450 goto end;
451 }
452
453 seq_printf(seq, "active limit: P%d:T%d\n"
Len Brown4be44fc2005-08-05 00:44:28 -0400454 "user limit: P%d:T%d\n"
455 "thermal limit: P%d:T%d\n",
456 pr->limit.state.px, pr->limit.state.tx,
457 pr->limit.user.px, pr->limit.user.tx,
458 pr->limit.thermal.px, pr->limit.thermal.tx);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459
Len Brown4be44fc2005-08-05 00:44:28 -0400460 end:
Patrick Mocheld550d982006-06-27 00:41:40 -0400461 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462}
463
464static int acpi_processor_limit_open_fs(struct inode *inode, struct file *file)
465{
466 return single_open(file, acpi_processor_limit_seq_show,
Len Brown4be44fc2005-08-05 00:44:28 -0400467 PDE(inode)->data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468}
469
Adrian Bunk757b1862006-01-07 13:19:00 -0500470static ssize_t acpi_processor_write_limit(struct file * file,
471 const char __user * buffer,
472 size_t count, loff_t * data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473{
Len Brown4be44fc2005-08-05 00:44:28 -0400474 int result = 0;
Jan Engelhardt50dd0962006-10-01 00:28:50 +0200475 struct seq_file *m = file->private_data;
476 struct acpi_processor *pr = m->private;
Len Brown4be44fc2005-08-05 00:44:28 -0400477 char limit_string[25] = { '\0' };
478 int px = 0;
479 int tx = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481
482 if (!pr || (count > sizeof(limit_string) - 1)) {
Patrick Mocheld550d982006-06-27 00:41:40 -0400483 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484 }
485
486 if (copy_from_user(limit_string, buffer, count)) {
Patrick Mocheld550d982006-06-27 00:41:40 -0400487 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488 }
489
490 limit_string[count] = '\0';
491
492 if (sscanf(limit_string, "%d:%d", &px, &tx) != 2) {
Len Brown64684632006-06-26 23:41:38 -0400493 printk(KERN_ERR PREFIX "Invalid data format\n");
Patrick Mocheld550d982006-06-27 00:41:40 -0400494 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 }
496
497 if (pr->flags.throttling) {
498 if ((tx < 0) || (tx > (pr->throttling.state_count - 1))) {
Len Brown64684632006-06-26 23:41:38 -0400499 printk(KERN_ERR PREFIX "Invalid tx\n");
Patrick Mocheld550d982006-06-27 00:41:40 -0400500 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501 }
502 pr->limit.user.tx = tx;
503 }
504
505 result = acpi_processor_apply_limit(pr);
506
Patrick Mocheld550d982006-06-27 00:41:40 -0400507 return count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508}
509
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510struct file_operations acpi_processor_limit_fops = {
Denis V. Lunevcf7acfa2008-04-29 01:02:27 -0700511 .owner = THIS_MODULE,
Len Brown4be44fc2005-08-05 00:44:28 -0400512 .open = acpi_processor_limit_open_fs,
513 .read = seq_read,
Arjan van de Vend479e902006-01-06 16:47:00 -0500514 .write = acpi_processor_write_limit,
Len Brown4be44fc2005-08-05 00:44:28 -0400515 .llseek = seq_lseek,
516 .release = single_release,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517};