1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  Intel menlow Driver for thermal management extension
  4 *
  5 *  Copyright (C) 2008 Intel Corp
  6 *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
  7 *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
  8 *
  9 *  This driver creates the sys I/F for programming the sensors.
 10 *  It also implements the driver for intel menlow memory controller (hardware
 11 *  id is INT0002) which makes use of the platform specific ACPI methods
 12 *  to get/set bandwidth.
 13 */
 14
 15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 16
 17#include <linux/acpi.h>
 18#include <linux/kernel.h>
 19#include <linux/module.h>
 20#include <linux/pci.h>
 21#include <linux/pm.h>
 22#include <linux/slab.h>
 23#include <linux/thermal.h>
 24#include <linux/types.h>
 25#include <linux/units.h>
 26
 27MODULE_AUTHOR("Thomas Sujith");
 28MODULE_AUTHOR("Zhang Rui");
 29MODULE_DESCRIPTION("Intel Menlow platform specific driver");
 30MODULE_LICENSE("GPL v2");
 31
 32/*
 33 * Memory controller device control
 34 */
 35
 36#define MEMORY_GET_BANDWIDTH "GTHS"
 37#define MEMORY_SET_BANDWIDTH "STHS"
 38#define MEMORY_ARG_CUR_BANDWIDTH 1
 39#define MEMORY_ARG_MAX_BANDWIDTH 0
 40
 41static void intel_menlow_unregister_sensor(void);
 42
 43/*
 44 * GTHS returning 'n' would mean that [0,n-1] states are supported
 45 * In that case max_cstate would be n-1
 46 * GTHS returning '0' would mean that no bandwidth control states are supported
 47 */
 48static int memory_get_max_bandwidth(struct thermal_cooling_device *cdev,
 49				    unsigned long *max_state)
 50{
 51	struct acpi_device *device = cdev->devdata;
 52	acpi_handle handle = device->handle;
 53	unsigned long long value;
 54	struct acpi_object_list arg_list;
 55	union acpi_object arg;
 56	acpi_status status = AE_OK;
 57
 58	arg_list.count = 1;
 59	arg_list.pointer = &arg;
 60	arg.type = ACPI_TYPE_INTEGER;
 61	arg.integer.value = MEMORY_ARG_MAX_BANDWIDTH;
 62	status = acpi_evaluate_integer(handle, MEMORY_GET_BANDWIDTH,
 63				       &arg_list, &value);
 64	if (ACPI_FAILURE(status))
 65		return -EFAULT;
 66
 67	if (!value)
 68		return -EINVAL;
 69
 70	*max_state = value - 1;
 71	return 0;
 72}
 73
 74static int memory_get_cur_bandwidth(struct thermal_cooling_device *cdev,
 75				    unsigned long *value)
 76{
 77	struct acpi_device *device = cdev->devdata;
 78	acpi_handle handle = device->handle;
 79	unsigned long long result;
 80	struct acpi_object_list arg_list;
 81	union acpi_object arg;
 82	acpi_status status = AE_OK;
 83
 84	arg_list.count = 1;
 85	arg_list.pointer = &arg;
 86	arg.type = ACPI_TYPE_INTEGER;
 87	arg.integer.value = MEMORY_ARG_CUR_BANDWIDTH;
 88	status = acpi_evaluate_integer(handle, MEMORY_GET_BANDWIDTH,
 89				       &arg_list, &result);
 90	if (ACPI_FAILURE(status))
 91		return -EFAULT;
 92
 93	*value = result;
 94	return 0;
 95}
 96
 97static int memory_set_cur_bandwidth(struct thermal_cooling_device *cdev,
 98				    unsigned long state)
 99{
100	struct acpi_device *device = cdev->devdata;
101	acpi_handle handle = device->handle;
102	struct acpi_object_list arg_list;
103	union acpi_object arg;
104	acpi_status status;
105	unsigned long long temp;
106	unsigned long max_state;
107
108	if (memory_get_max_bandwidth(cdev, &max_state))
109		return -EFAULT;
110
111	if (state > max_state)
112		return -EINVAL;
113
114	arg_list.count = 1;
115	arg_list.pointer = &arg;
116	arg.type = ACPI_TYPE_INTEGER;
117	arg.integer.value = state;
118
119	status =
120	    acpi_evaluate_integer(handle, MEMORY_SET_BANDWIDTH, &arg_list,
121				  &temp);
122
123	pr_info("Bandwidth value was %ld: status is %d\n", state, status);
124	if (ACPI_FAILURE(status))
125		return -EFAULT;
126
127	return 0;
128}
129
130static const struct thermal_cooling_device_ops memory_cooling_ops = {
131	.get_max_state = memory_get_max_bandwidth,
132	.get_cur_state = memory_get_cur_bandwidth,
133	.set_cur_state = memory_set_cur_bandwidth,
134};
135
136/*
137 * Memory Device Management
138 */
139static int intel_menlow_memory_add(struct acpi_device *device)
140{
141	int result = -ENODEV;
142	struct thermal_cooling_device *cdev;
143
144	if (!device)
145		return -EINVAL;
146
147	if (!acpi_has_method(device->handle, MEMORY_GET_BANDWIDTH))
148		goto end;
149
150	if (!acpi_has_method(device->handle, MEMORY_SET_BANDWIDTH))
151		goto end;
152
153	cdev = thermal_cooling_device_register("Memory controller", device,
154					       &memory_cooling_ops);
155	if (IS_ERR(cdev)) {
156		result = PTR_ERR(cdev);
157		goto end;
158	}
159
160	device->driver_data = cdev;
161	result = sysfs_create_link(&device->dev.kobj,
162				&cdev->device.kobj, "thermal_cooling");
163	if (result)
164		goto unregister;
165
166	result = sysfs_create_link(&cdev->device.kobj,
167				&device->dev.kobj, "device");
168	if (result) {
169		sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
170		goto unregister;
171	}
172
173 end:
174	return result;
175
176 unregister:
177	thermal_cooling_device_unregister(cdev);
178	return result;
179
180}
181
182static void intel_menlow_memory_remove(struct acpi_device *device)
183{
184	struct thermal_cooling_device *cdev;
185
186	if (!device)
187		return;
188
189	cdev = acpi_driver_data(device);
190	if (!cdev)
191		return;
192
193	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
194	sysfs_remove_link(&cdev->device.kobj, "device");
195	thermal_cooling_device_unregister(cdev);
196}
197
198static const struct acpi_device_id intel_menlow_memory_ids[] = {
199	{"INT0002", 0},
200	{"", 0},
201};
202
203static struct acpi_driver intel_menlow_memory_driver = {
204	.name = "intel_menlow_thermal_control",
205	.ids = intel_menlow_memory_ids,
206	.ops = {
207		.add = intel_menlow_memory_add,
208		.remove = intel_menlow_memory_remove,
209		},
210};
211
212/*
213 * Sensor control on menlow platform
214 */
215
216#define THERMAL_AUX0 0
217#define THERMAL_AUX1 1
218#define GET_AUX0 "GAX0"
219#define GET_AUX1 "GAX1"
220#define SET_AUX0 "SAX0"
221#define SET_AUX1 "SAX1"
222
223struct intel_menlow_attribute {
224	struct device_attribute attr;
225	struct device *device;
226	acpi_handle handle;
227	struct list_head node;
228};
229
230static LIST_HEAD(intel_menlow_attr_list);
231static DEFINE_MUTEX(intel_menlow_attr_lock);
232
233/*
234 * sensor_get_auxtrip - get the current auxtrip value from sensor
235 * @name: Thermalzone name
236 * @auxtype : AUX0/AUX1
237 * @buf: syfs buffer
238 */
239static int sensor_get_auxtrip(acpi_handle handle, int index,
240							unsigned long long *value)
241{
242	acpi_status status;
243
244	if ((index != 0 && index != 1) || !value)
245		return -EINVAL;
246
247	status = acpi_evaluate_integer(handle, index ? GET_AUX1 : GET_AUX0,
248				       NULL, value);
249	if (ACPI_FAILURE(status))
250		return -EIO;
251
252	return 0;
253}
254
255/*
256 * sensor_set_auxtrip - set the new auxtrip value to sensor
257 * @name: Thermalzone name
258 * @auxtype : AUX0/AUX1
259 * @buf: syfs buffer
260 */
261static int sensor_set_auxtrip(acpi_handle handle, int index, int value)
262{
263	acpi_status status;
264	union acpi_object arg = {
265		ACPI_TYPE_INTEGER
266	};
267	struct acpi_object_list args = {
268		1, &arg
269	};
270	unsigned long long temp;
271
272	if (index != 0 && index != 1)
273		return -EINVAL;
274
275	status = acpi_evaluate_integer(handle, index ? GET_AUX0 : GET_AUX1,
276				       NULL, &temp);
277	if (ACPI_FAILURE(status))
278		return -EIO;
279	if ((index && value < temp) || (!index && value > temp))
280		return -EINVAL;
281
282	arg.integer.value = value;
283	status = acpi_evaluate_integer(handle, index ? SET_AUX1 : SET_AUX0,
284				       &args, &temp);
285	if (ACPI_FAILURE(status))
286		return -EIO;
287
288	/* do we need to check the return value of SAX0/SAX1 ? */
289
290	return 0;
291}
292
293#define to_intel_menlow_attr(_attr)	\
294	container_of(_attr, struct intel_menlow_attribute, attr)
295
296static ssize_t aux_show(struct device *dev, struct device_attribute *dev_attr,
297			char *buf, int idx)
298{
299	struct intel_menlow_attribute *attr = to_intel_menlow_attr(dev_attr);
300	unsigned long long value;
301	int result;
302
303	result = sensor_get_auxtrip(attr->handle, idx, &value);
304	if (result)
305		return result;
306
307	return sprintf(buf, "%lu", deci_kelvin_to_celsius(value));
308}
309
310static ssize_t aux0_show(struct device *dev,
311			 struct device_attribute *dev_attr, char *buf)
312{
313	return aux_show(dev, dev_attr, buf, 0);
314}
315
316static ssize_t aux1_show(struct device *dev,
317			 struct device_attribute *dev_attr, char *buf)
318{
319	return aux_show(dev, dev_attr, buf, 1);
320}
321
322static ssize_t aux_store(struct device *dev, struct device_attribute *dev_attr,
323			 const char *buf, size_t count, int idx)
324{
325	struct intel_menlow_attribute *attr = to_intel_menlow_attr(dev_attr);
326	int value;
327	int result;
328
329	/*Sanity check; should be a positive integer */
330	if (!sscanf(buf, "%d", &value))
331		return -EINVAL;
332
333	if (value < 0)
334		return -EINVAL;
335
336	result = sensor_set_auxtrip(attr->handle, idx,
337				    celsius_to_deci_kelvin(value));
338	return result ? result : count;
339}
340
341static ssize_t aux0_store(struct device *dev,
342			  struct device_attribute *dev_attr,
343			  const char *buf, size_t count)
344{
345	return aux_store(dev, dev_attr, buf, count, 0);
346}
347
348static ssize_t aux1_store(struct device *dev,
349			  struct device_attribute *dev_attr,
350			  const char *buf, size_t count)
351{
352	return aux_store(dev, dev_attr, buf, count, 1);
353}
354
355/* BIOS can enable/disable the thermal user application in dabney platform */
356#define BIOS_ENABLED "\\_TZ.GSTS"
357static ssize_t bios_enabled_show(struct device *dev,
358				 struct device_attribute *attr, char *buf)
359{
360	acpi_status status;
361	unsigned long long bios_enabled;
362
363	status = acpi_evaluate_integer(NULL, BIOS_ENABLED, NULL, &bios_enabled);
364	if (ACPI_FAILURE(status))
365		return -ENODEV;
366
367	return sprintf(buf, "%s\n", bios_enabled ? "enabled" : "disabled");
368}
369
370static int intel_menlow_add_one_attribute(char *name, umode_t mode, void *show,
371					  void *store, struct device *dev,
372					  acpi_handle handle)
373{
374	struct intel_menlow_attribute *attr;
375	int result;
376
377	attr = kzalloc(sizeof(struct intel_menlow_attribute), GFP_KERNEL);
378	if (!attr)
379		return -ENOMEM;
380
381	sysfs_attr_init(&attr->attr.attr); /* That is consistent naming :D */
382	attr->attr.attr.name = name;
383	attr->attr.attr.mode = mode;
384	attr->attr.show = show;
385	attr->attr.store = store;
386	attr->device = dev;
387	attr->handle = handle;
388
389	result = device_create_file(dev, &attr->attr);
390	if (result) {
391		kfree(attr);
392		return result;
393	}
394
395	mutex_lock(&intel_menlow_attr_lock);
396	list_add_tail(&attr->node, &intel_menlow_attr_list);
397	mutex_unlock(&intel_menlow_attr_lock);
398
399	return 0;
400}
401
402static acpi_status intel_menlow_register_sensor(acpi_handle handle, u32 lvl,
403						void *context, void **rv)
404{
405	acpi_status status;
406	acpi_handle dummy;
407	struct thermal_zone_device *thermal;
408	int result;
409
410	result = acpi_bus_get_private_data(handle, (void **)&thermal);
411	if (result)
412		return 0;
413
414	/* _TZ must have the AUX0/1 methods */
415	status = acpi_get_handle(handle, GET_AUX0, &dummy);
416	if (ACPI_FAILURE(status))
417		return (status == AE_NOT_FOUND) ? AE_OK : status;
418
419	status = acpi_get_handle(handle, SET_AUX0, &dummy);
420	if (ACPI_FAILURE(status))
421		return (status == AE_NOT_FOUND) ? AE_OK : status;
422
423	result = intel_menlow_add_one_attribute("aux0", 0644,
424						aux0_show, aux0_store,
425						&thermal->device, handle);
426	if (result)
427		return AE_ERROR;
428
429	status = acpi_get_handle(handle, GET_AUX1, &dummy);
430	if (ACPI_FAILURE(status))
431		goto aux1_not_found;
432
433	status = acpi_get_handle(handle, SET_AUX1, &dummy);
434	if (ACPI_FAILURE(status))
435		goto aux1_not_found;
436
437	result = intel_menlow_add_one_attribute("aux1", 0644,
438						aux1_show, aux1_store,
439						&thermal->device, handle);
440	if (result) {
441		intel_menlow_unregister_sensor();
442		return AE_ERROR;
443	}
444
445	/*
446	 * create the "dabney_enabled" attribute which means the user app
447	 * should be loaded or not
448	 */
449
450	result = intel_menlow_add_one_attribute("bios_enabled", 0444,
451						bios_enabled_show, NULL,
452						&thermal->device, handle);
453	if (result) {
454		intel_menlow_unregister_sensor();
455		return AE_ERROR;
456	}
457
458	return AE_OK;
459
460 aux1_not_found:
461	if (status == AE_NOT_FOUND)
462		return AE_OK;
463
464	intel_menlow_unregister_sensor();
465	return status;
466}
467
468static void intel_menlow_unregister_sensor(void)
469{
470	struct intel_menlow_attribute *pos, *next;
471
472	mutex_lock(&intel_menlow_attr_lock);
473	list_for_each_entry_safe(pos, next, &intel_menlow_attr_list, node) {
474		list_del(&pos->node);
475		device_remove_file(pos->device, &pos->attr);
476		kfree(pos);
477	}
478	mutex_unlock(&intel_menlow_attr_lock);
479
480	return;
481}
482
483static int __init intel_menlow_module_init(void)
484{
485	int result = -ENODEV;
486	acpi_status status;
487	unsigned long long enable;
488
489	if (acpi_disabled)
490		return result;
491
492	/* Looking for the \_TZ.GSTS method */
493	status = acpi_evaluate_integer(NULL, BIOS_ENABLED, NULL, &enable);
494	if (ACPI_FAILURE(status) || !enable)
495		return -ENODEV;
496
497	/* Looking for ACPI device MEM0 with hardware id INT0002 */
498	result = acpi_bus_register_driver(&intel_menlow_memory_driver);
499	if (result)
500		return result;
501
502	/* Looking for sensors in each ACPI thermal zone */
503	status = acpi_walk_namespace(ACPI_TYPE_THERMAL, ACPI_ROOT_OBJECT,
504				     ACPI_UINT32_MAX,
505				     intel_menlow_register_sensor, NULL, NULL, NULL);
506	if (ACPI_FAILURE(status)) {
507		acpi_bus_unregister_driver(&intel_menlow_memory_driver);
508		return -ENODEV;
509	}
510
511	return 0;
512}
513
514static void __exit intel_menlow_module_exit(void)
515{
516	acpi_bus_unregister_driver(&intel_menlow_memory_driver);
517	intel_menlow_unregister_sensor();
518}
519
520module_init(intel_menlow_module_init);
521module_exit(intel_menlow_module_exit);