xref: /linux/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2  * Copyright 2012 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  */
23 
24 #include <linux/pci.h>
25 #include <linux/acpi.h>
26 #include <linux/slab.h>
27 #include <linux/power_supply.h>
28 #include <linux/pm_runtime.h>
29 #include <acpi/video.h>
30 #include <drm/drmP.h>
31 #include <drm/drm_crtc_helper.h>
32 #include "amdgpu.h"
33 #include "amd_acpi.h"
34 #include "atom.h"
35 
36 extern void amdgpu_pm_acpi_event_handler(struct amdgpu_device *adev);
37 /* Call the ATIF method
38  */
39 /**
40  * amdgpu_atif_call - call an ATIF method
41  *
42  * @handle: acpi handle
43  * @function: the ATIF function to execute
44  * @params: ATIF function params
45  *
46  * Executes the requested ATIF function (all asics).
47  * Returns a pointer to the acpi output buffer.
48  */
49 static union acpi_object *amdgpu_atif_call(acpi_handle handle, int function,
50 		struct acpi_buffer *params)
51 {
52 	acpi_status status;
53 	union acpi_object atif_arg_elements[2];
54 	struct acpi_object_list atif_arg;
55 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
56 
57 	atif_arg.count = 2;
58 	atif_arg.pointer = &atif_arg_elements[0];
59 
60 	atif_arg_elements[0].type = ACPI_TYPE_INTEGER;
61 	atif_arg_elements[0].integer.value = function;
62 
63 	if (params) {
64 		atif_arg_elements[1].type = ACPI_TYPE_BUFFER;
65 		atif_arg_elements[1].buffer.length = params->length;
66 		atif_arg_elements[1].buffer.pointer = params->pointer;
67 	} else {
68 		/* We need a second fake parameter */
69 		atif_arg_elements[1].type = ACPI_TYPE_INTEGER;
70 		atif_arg_elements[1].integer.value = 0;
71 	}
72 
73 	status = acpi_evaluate_object(handle, "ATIF", &atif_arg, &buffer);
74 
75 	/* Fail only if calling the method fails and ATIF is supported */
76 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
77 		DRM_DEBUG_DRIVER("failed to evaluate ATIF got %s\n",
78 				 acpi_format_exception(status));
79 		kfree(buffer.pointer);
80 		return NULL;
81 	}
82 
83 	return buffer.pointer;
84 }
85 
86 /**
87  * amdgpu_atif_parse_notification - parse supported notifications
88  *
89  * @n: supported notifications struct
90  * @mask: supported notifications mask from ATIF
91  *
92  * Use the supported notifications mask from ATIF function
93  * ATIF_FUNCTION_VERIFY_INTERFACE to determine what notifications
94  * are supported (all asics).
95  */
96 static void amdgpu_atif_parse_notification(struct amdgpu_atif_notifications *n, u32 mask)
97 {
98 	n->display_switch = mask & ATIF_DISPLAY_SWITCH_REQUEST_SUPPORTED;
99 	n->expansion_mode_change = mask & ATIF_EXPANSION_MODE_CHANGE_REQUEST_SUPPORTED;
100 	n->thermal_state = mask & ATIF_THERMAL_STATE_CHANGE_REQUEST_SUPPORTED;
101 	n->forced_power_state = mask & ATIF_FORCED_POWER_STATE_CHANGE_REQUEST_SUPPORTED;
102 	n->system_power_state = mask & ATIF_SYSTEM_POWER_SOURCE_CHANGE_REQUEST_SUPPORTED;
103 	n->display_conf_change = mask & ATIF_DISPLAY_CONF_CHANGE_REQUEST_SUPPORTED;
104 	n->px_gfx_switch = mask & ATIF_PX_GFX_SWITCH_REQUEST_SUPPORTED;
105 	n->brightness_change = mask & ATIF_PANEL_BRIGHTNESS_CHANGE_REQUEST_SUPPORTED;
106 	n->dgpu_display_event = mask & ATIF_DGPU_DISPLAY_EVENT_SUPPORTED;
107 }
108 
109 /**
110  * amdgpu_atif_parse_functions - parse supported functions
111  *
112  * @f: supported functions struct
113  * @mask: supported functions mask from ATIF
114  *
115  * Use the supported functions mask from ATIF function
116  * ATIF_FUNCTION_VERIFY_INTERFACE to determine what functions
117  * are supported (all asics).
118  */
119 static void amdgpu_atif_parse_functions(struct amdgpu_atif_functions *f, u32 mask)
120 {
121 	f->system_params = mask & ATIF_GET_SYSTEM_PARAMETERS_SUPPORTED;
122 	f->sbios_requests = mask & ATIF_GET_SYSTEM_BIOS_REQUESTS_SUPPORTED;
123 	f->select_active_disp = mask & ATIF_SELECT_ACTIVE_DISPLAYS_SUPPORTED;
124 	f->lid_state = mask & ATIF_GET_LID_STATE_SUPPORTED;
125 	f->get_tv_standard = mask & ATIF_GET_TV_STANDARD_FROM_CMOS_SUPPORTED;
126 	f->set_tv_standard = mask & ATIF_SET_TV_STANDARD_IN_CMOS_SUPPORTED;
127 	f->get_panel_expansion_mode = mask & ATIF_GET_PANEL_EXPANSION_MODE_FROM_CMOS_SUPPORTED;
128 	f->set_panel_expansion_mode = mask & ATIF_SET_PANEL_EXPANSION_MODE_IN_CMOS_SUPPORTED;
129 	f->temperature_change = mask & ATIF_TEMPERATURE_CHANGE_NOTIFICATION_SUPPORTED;
130 	f->graphics_device_types = mask & ATIF_GET_GRAPHICS_DEVICE_TYPES_SUPPORTED;
131 }
132 
133 /**
134  * amdgpu_atif_verify_interface - verify ATIF
135  *
136  * @handle: acpi handle
137  * @atif: amdgpu atif struct
138  *
139  * Execute the ATIF_FUNCTION_VERIFY_INTERFACE ATIF function
140  * to initialize ATIF and determine what features are supported
141  * (all asics).
142  * returns 0 on success, error on failure.
143  */
144 static int amdgpu_atif_verify_interface(acpi_handle handle,
145 		struct amdgpu_atif *atif)
146 {
147 	union acpi_object *info;
148 	struct atif_verify_interface output;
149 	size_t size;
150 	int err = 0;
151 
152 	info = amdgpu_atif_call(handle, ATIF_FUNCTION_VERIFY_INTERFACE, NULL);
153 	if (!info)
154 		return -EIO;
155 
156 	memset(&output, 0, sizeof(output));
157 
158 	size = *(u16 *) info->buffer.pointer;
159 	if (size < 12) {
160 		DRM_INFO("ATIF buffer is too small: %zu\n", size);
161 		err = -EINVAL;
162 		goto out;
163 	}
164 	size = min(sizeof(output), size);
165 
166 	memcpy(&output, info->buffer.pointer, size);
167 
168 	/* TODO: check version? */
169 	DRM_DEBUG_DRIVER("ATIF version %u\n", output.version);
170 
171 	amdgpu_atif_parse_notification(&atif->notifications, output.notification_mask);
172 	amdgpu_atif_parse_functions(&atif->functions, output.function_bits);
173 
174 out:
175 	kfree(info);
176 	return err;
177 }
178 
179 /**
180  * amdgpu_atif_get_notification_params - determine notify configuration
181  *
182  * @handle: acpi handle
183  * @n: atif notification configuration struct
184  *
185  * Execute the ATIF_FUNCTION_GET_SYSTEM_PARAMETERS ATIF function
186  * to determine if a notifier is used and if so which one
187  * (all asics).  This is either Notify(VGA, 0x81) or Notify(VGA, n)
188  * where n is specified in the result if a notifier is used.
189  * Returns 0 on success, error on failure.
190  */
191 static int amdgpu_atif_get_notification_params(acpi_handle handle,
192 		struct amdgpu_atif_notification_cfg *n)
193 {
194 	union acpi_object *info;
195 	struct atif_system_params params;
196 	size_t size;
197 	int err = 0;
198 
199 	info = amdgpu_atif_call(handle, ATIF_FUNCTION_GET_SYSTEM_PARAMETERS, NULL);
200 	if (!info) {
201 		err = -EIO;
202 		goto out;
203 	}
204 
205 	size = *(u16 *) info->buffer.pointer;
206 	if (size < 10) {
207 		err = -EINVAL;
208 		goto out;
209 	}
210 
211 	memset(&params, 0, sizeof(params));
212 	size = min(sizeof(params), size);
213 	memcpy(&params, info->buffer.pointer, size);
214 
215 	DRM_DEBUG_DRIVER("SYSTEM_PARAMS: mask = %#x, flags = %#x\n",
216 			params.flags, params.valid_mask);
217 	params.flags = params.flags & params.valid_mask;
218 
219 	if ((params.flags & ATIF_NOTIFY_MASK) == ATIF_NOTIFY_NONE) {
220 		n->enabled = false;
221 		n->command_code = 0;
222 	} else if ((params.flags & ATIF_NOTIFY_MASK) == ATIF_NOTIFY_81) {
223 		n->enabled = true;
224 		n->command_code = 0x81;
225 	} else {
226 		if (size < 11) {
227 			err = -EINVAL;
228 			goto out;
229 		}
230 		n->enabled = true;
231 		n->command_code = params.command_code;
232 	}
233 
234 out:
235 	DRM_DEBUG_DRIVER("Notification %s, command code = %#x\n",
236 			(n->enabled ? "enabled" : "disabled"),
237 			n->command_code);
238 	kfree(info);
239 	return err;
240 }
241 
242 /**
243  * amdgpu_atif_get_sbios_requests - get requested sbios event
244  *
245  * @handle: acpi handle
246  * @req: atif sbios request struct
247  *
248  * Execute the ATIF_FUNCTION_GET_SYSTEM_BIOS_REQUESTS ATIF function
249  * to determine what requests the sbios is making to the driver
250  * (all asics).
251  * Returns 0 on success, error on failure.
252  */
253 static int amdgpu_atif_get_sbios_requests(acpi_handle handle,
254 		struct atif_sbios_requests *req)
255 {
256 	union acpi_object *info;
257 	size_t size;
258 	int count = 0;
259 
260 	info = amdgpu_atif_call(handle, ATIF_FUNCTION_GET_SYSTEM_BIOS_REQUESTS, NULL);
261 	if (!info)
262 		return -EIO;
263 
264 	size = *(u16 *)info->buffer.pointer;
265 	if (size < 0xd) {
266 		count = -EINVAL;
267 		goto out;
268 	}
269 	memset(req, 0, sizeof(*req));
270 
271 	size = min(sizeof(*req), size);
272 	memcpy(req, info->buffer.pointer, size);
273 	DRM_DEBUG_DRIVER("SBIOS pending requests: %#x\n", req->pending);
274 
275 	count = hweight32(req->pending);
276 
277 out:
278 	kfree(info);
279 	return count;
280 }
281 
282 /**
283  * amdgpu_atif_handler - handle ATIF notify requests
284  *
285  * @adev: amdgpu_device pointer
286  * @event: atif sbios request struct
287  *
288  * Checks the acpi event and if it matches an atif event,
289  * handles it.
290  * Returns NOTIFY code
291  */
292 int amdgpu_atif_handler(struct amdgpu_device *adev,
293 			struct acpi_bus_event *event)
294 {
295 	struct amdgpu_atif *atif = &adev->atif;
296 	struct atif_sbios_requests req;
297 	acpi_handle handle;
298 	int count;
299 
300 	DRM_DEBUG_DRIVER("event, device_class = %s, type = %#x\n",
301 			event->device_class, event->type);
302 
303 	if (strcmp(event->device_class, ACPI_VIDEO_CLASS) != 0)
304 		return NOTIFY_DONE;
305 
306 	if (!atif->notification_cfg.enabled ||
307 	    event->type != atif->notification_cfg.command_code)
308 		/* Not our event */
309 		return NOTIFY_DONE;
310 
311 	/* Check pending SBIOS requests */
312 	handle = ACPI_HANDLE(&adev->pdev->dev);
313 	count = amdgpu_atif_get_sbios_requests(handle, &req);
314 
315 	if (count <= 0)
316 		return NOTIFY_DONE;
317 
318 	DRM_DEBUG_DRIVER("ATIF: %d pending SBIOS requests\n", count);
319 
320 	if (req.pending & ATIF_PANEL_BRIGHTNESS_CHANGE_REQUEST) {
321 		struct amdgpu_encoder *enc = atif->encoder_for_bl;
322 
323 		if (enc) {
324 			struct amdgpu_encoder_atom_dig *dig = enc->enc_priv;
325 
326 			DRM_DEBUG_DRIVER("Changing brightness to %d\n",
327 					req.backlight_level);
328 
329 			amdgpu_display_backlight_set_level(adev, enc, req.backlight_level);
330 
331 #if defined(CONFIG_BACKLIGHT_CLASS_DEVICE) || defined(CONFIG_BACKLIGHT_CLASS_DEVICE_MODULE)
332 			backlight_force_update(dig->bl_dev,
333 					       BACKLIGHT_UPDATE_HOTKEY);
334 #endif
335 		}
336 	}
337 	if (req.pending & ATIF_DGPU_DISPLAY_EVENT) {
338 		if ((adev->flags & AMD_IS_PX) &&
339 		    amdgpu_atpx_dgpu_req_power_for_displays()) {
340 			pm_runtime_get_sync(adev->ddev->dev);
341 			/* Just fire off a uevent and let userspace tell us what to do */
342 			drm_helper_hpd_irq_event(adev->ddev);
343 			pm_runtime_mark_last_busy(adev->ddev->dev);
344 			pm_runtime_put_autosuspend(adev->ddev->dev);
345 		}
346 	}
347 	/* TODO: check other events */
348 
349 	/* We've handled the event, stop the notifier chain. The ACPI interface
350 	 * overloads ACPI_VIDEO_NOTIFY_PROBE, we don't want to send that to
351 	 * userspace if the event was generated only to signal a SBIOS
352 	 * request.
353 	 */
354 	return NOTIFY_BAD;
355 }
356 
357 /* Call the ATCS method
358  */
359 /**
360  * amdgpu_atcs_call - call an ATCS method
361  *
362  * @handle: acpi handle
363  * @function: the ATCS function to execute
364  * @params: ATCS function params
365  *
366  * Executes the requested ATCS function (all asics).
367  * Returns a pointer to the acpi output buffer.
368  */
369 static union acpi_object *amdgpu_atcs_call(acpi_handle handle, int function,
370 					   struct acpi_buffer *params)
371 {
372 	acpi_status status;
373 	union acpi_object atcs_arg_elements[2];
374 	struct acpi_object_list atcs_arg;
375 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
376 
377 	atcs_arg.count = 2;
378 	atcs_arg.pointer = &atcs_arg_elements[0];
379 
380 	atcs_arg_elements[0].type = ACPI_TYPE_INTEGER;
381 	atcs_arg_elements[0].integer.value = function;
382 
383 	if (params) {
384 		atcs_arg_elements[1].type = ACPI_TYPE_BUFFER;
385 		atcs_arg_elements[1].buffer.length = params->length;
386 		atcs_arg_elements[1].buffer.pointer = params->pointer;
387 	} else {
388 		/* We need a second fake parameter */
389 		atcs_arg_elements[1].type = ACPI_TYPE_INTEGER;
390 		atcs_arg_elements[1].integer.value = 0;
391 	}
392 
393 	status = acpi_evaluate_object(handle, "ATCS", &atcs_arg, &buffer);
394 
395 	/* Fail only if calling the method fails and ATIF is supported */
396 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
397 		DRM_DEBUG_DRIVER("failed to evaluate ATCS got %s\n",
398 				 acpi_format_exception(status));
399 		kfree(buffer.pointer);
400 		return NULL;
401 	}
402 
403 	return buffer.pointer;
404 }
405 
406 /**
407  * amdgpu_atcs_parse_functions - parse supported functions
408  *
409  * @f: supported functions struct
410  * @mask: supported functions mask from ATCS
411  *
412  * Use the supported functions mask from ATCS function
413  * ATCS_FUNCTION_VERIFY_INTERFACE to determine what functions
414  * are supported (all asics).
415  */
416 static void amdgpu_atcs_parse_functions(struct amdgpu_atcs_functions *f, u32 mask)
417 {
418 	f->get_ext_state = mask & ATCS_GET_EXTERNAL_STATE_SUPPORTED;
419 	f->pcie_perf_req = mask & ATCS_PCIE_PERFORMANCE_REQUEST_SUPPORTED;
420 	f->pcie_dev_rdy = mask & ATCS_PCIE_DEVICE_READY_NOTIFICATION_SUPPORTED;
421 	f->pcie_bus_width = mask & ATCS_SET_PCIE_BUS_WIDTH_SUPPORTED;
422 }
423 
424 /**
425  * amdgpu_atcs_verify_interface - verify ATCS
426  *
427  * @handle: acpi handle
428  * @atcs: amdgpu atcs struct
429  *
430  * Execute the ATCS_FUNCTION_VERIFY_INTERFACE ATCS function
431  * to initialize ATCS and determine what features are supported
432  * (all asics).
433  * returns 0 on success, error on failure.
434  */
435 static int amdgpu_atcs_verify_interface(acpi_handle handle,
436 					struct amdgpu_atcs *atcs)
437 {
438 	union acpi_object *info;
439 	struct atcs_verify_interface output;
440 	size_t size;
441 	int err = 0;
442 
443 	info = amdgpu_atcs_call(handle, ATCS_FUNCTION_VERIFY_INTERFACE, NULL);
444 	if (!info)
445 		return -EIO;
446 
447 	memset(&output, 0, sizeof(output));
448 
449 	size = *(u16 *) info->buffer.pointer;
450 	if (size < 8) {
451 		DRM_INFO("ATCS buffer is too small: %zu\n", size);
452 		err = -EINVAL;
453 		goto out;
454 	}
455 	size = min(sizeof(output), size);
456 
457 	memcpy(&output, info->buffer.pointer, size);
458 
459 	/* TODO: check version? */
460 	DRM_DEBUG_DRIVER("ATCS version %u\n", output.version);
461 
462 	amdgpu_atcs_parse_functions(&atcs->functions, output.function_bits);
463 
464 out:
465 	kfree(info);
466 	return err;
467 }
468 
469 /**
470  * amdgpu_acpi_is_pcie_performance_request_supported
471  *
472  * @adev: amdgpu_device pointer
473  *
474  * Check if the ATCS pcie_perf_req and pcie_dev_rdy methods
475  * are supported (all asics).
476  * returns true if supported, false if not.
477  */
478 bool amdgpu_acpi_is_pcie_performance_request_supported(struct amdgpu_device *adev)
479 {
480 	struct amdgpu_atcs *atcs = &adev->atcs;
481 
482 	if (atcs->functions.pcie_perf_req && atcs->functions.pcie_dev_rdy)
483 		return true;
484 
485 	return false;
486 }
487 
488 /**
489  * amdgpu_acpi_pcie_notify_device_ready
490  *
491  * @adev: amdgpu_device pointer
492  *
493  * Executes the PCIE_DEVICE_READY_NOTIFICATION method
494  * (all asics).
495  * returns 0 on success, error on failure.
496  */
497 int amdgpu_acpi_pcie_notify_device_ready(struct amdgpu_device *adev)
498 {
499 	acpi_handle handle;
500 	union acpi_object *info;
501 	struct amdgpu_atcs *atcs = &adev->atcs;
502 
503 	/* Get the device handle */
504 	handle = ACPI_HANDLE(&adev->pdev->dev);
505 	if (!handle)
506 		return -EINVAL;
507 
508 	if (!atcs->functions.pcie_dev_rdy)
509 		return -EINVAL;
510 
511 	info = amdgpu_atcs_call(handle, ATCS_FUNCTION_PCIE_DEVICE_READY_NOTIFICATION, NULL);
512 	if (!info)
513 		return -EIO;
514 
515 	kfree(info);
516 
517 	return 0;
518 }
519 
520 /**
521  * amdgpu_acpi_pcie_performance_request
522  *
523  * @adev: amdgpu_device pointer
524  * @perf_req: requested perf level (pcie gen speed)
525  * @advertise: set advertise caps flag if set
526  *
527  * Executes the PCIE_PERFORMANCE_REQUEST method to
528  * change the pcie gen speed (all asics).
529  * returns 0 on success, error on failure.
530  */
531 int amdgpu_acpi_pcie_performance_request(struct amdgpu_device *adev,
532 					 u8 perf_req, bool advertise)
533 {
534 	acpi_handle handle;
535 	union acpi_object *info;
536 	struct amdgpu_atcs *atcs = &adev->atcs;
537 	struct atcs_pref_req_input atcs_input;
538 	struct atcs_pref_req_output atcs_output;
539 	struct acpi_buffer params;
540 	size_t size;
541 	u32 retry = 3;
542 
543 	/* Get the device handle */
544 	handle = ACPI_HANDLE(&adev->pdev->dev);
545 	if (!handle)
546 		return -EINVAL;
547 
548 	if (!atcs->functions.pcie_perf_req)
549 		return -EINVAL;
550 
551 	atcs_input.size = sizeof(struct atcs_pref_req_input);
552 	/* client id (bit 2-0: func num, 7-3: dev num, 15-8: bus num) */
553 	atcs_input.client_id = adev->pdev->devfn | (adev->pdev->bus->number << 8);
554 	atcs_input.valid_flags_mask = ATCS_VALID_FLAGS_MASK;
555 	atcs_input.flags = ATCS_WAIT_FOR_COMPLETION;
556 	if (advertise)
557 		atcs_input.flags |= ATCS_ADVERTISE_CAPS;
558 	atcs_input.req_type = ATCS_PCIE_LINK_SPEED;
559 	atcs_input.perf_req = perf_req;
560 
561 	params.length = sizeof(struct atcs_pref_req_input);
562 	params.pointer = &atcs_input;
563 
564 	while (retry--) {
565 		info = amdgpu_atcs_call(handle, ATCS_FUNCTION_PCIE_PERFORMANCE_REQUEST, &params);
566 		if (!info)
567 			return -EIO;
568 
569 		memset(&atcs_output, 0, sizeof(atcs_output));
570 
571 		size = *(u16 *) info->buffer.pointer;
572 		if (size < 3) {
573 			DRM_INFO("ATCS buffer is too small: %zu\n", size);
574 			kfree(info);
575 			return -EINVAL;
576 		}
577 		size = min(sizeof(atcs_output), size);
578 
579 		memcpy(&atcs_output, info->buffer.pointer, size);
580 
581 		kfree(info);
582 
583 		switch (atcs_output.ret_val) {
584 		case ATCS_REQUEST_REFUSED:
585 		default:
586 			return -EINVAL;
587 		case ATCS_REQUEST_COMPLETE:
588 			return 0;
589 		case ATCS_REQUEST_IN_PROGRESS:
590 			udelay(10);
591 			break;
592 		}
593 	}
594 
595 	return 0;
596 }
597 
598 /**
599  * amdgpu_acpi_event - handle notify events
600  *
601  * @nb: notifier block
602  * @val: val
603  * @data: acpi event
604  *
605  * Calls relevant amdgpu functions in response to various
606  * acpi events.
607  * Returns NOTIFY code
608  */
609 static int amdgpu_acpi_event(struct notifier_block *nb,
610 			     unsigned long val,
611 			     void *data)
612 {
613 	struct amdgpu_device *adev = container_of(nb, struct amdgpu_device, acpi_nb);
614 	struct acpi_bus_event *entry = (struct acpi_bus_event *)data;
615 
616 	if (strcmp(entry->device_class, ACPI_AC_CLASS) == 0) {
617 		if (power_supply_is_system_supplied() > 0)
618 			DRM_DEBUG_DRIVER("pm: AC\n");
619 		else
620 			DRM_DEBUG_DRIVER("pm: DC\n");
621 
622 		amdgpu_pm_acpi_event_handler(adev);
623 	}
624 
625 	/* Check for pending SBIOS requests */
626 	return amdgpu_atif_handler(adev, entry);
627 }
628 
629 /* Call all ACPI methods here */
630 /**
631  * amdgpu_acpi_init - init driver acpi support
632  *
633  * @adev: amdgpu_device pointer
634  *
635  * Verifies the AMD ACPI interfaces and registers with the acpi
636  * notifier chain (all asics).
637  * Returns 0 on success, error on failure.
638  */
639 int amdgpu_acpi_init(struct amdgpu_device *adev)
640 {
641 	acpi_handle handle;
642 	struct amdgpu_atif *atif = &adev->atif;
643 	struct amdgpu_atcs *atcs = &adev->atcs;
644 	int ret;
645 
646 	/* Get the device handle */
647 	handle = ACPI_HANDLE(&adev->pdev->dev);
648 
649 	if (!adev->bios || !handle)
650 		return 0;
651 
652 	/* Call the ATCS method */
653 	ret = amdgpu_atcs_verify_interface(handle, atcs);
654 	if (ret) {
655 		DRM_DEBUG_DRIVER("Call to ATCS verify_interface failed: %d\n", ret);
656 	}
657 
658 	/* Call the ATIF method */
659 	ret = amdgpu_atif_verify_interface(handle, atif);
660 	if (ret) {
661 		DRM_DEBUG_DRIVER("Call to ATIF verify_interface failed: %d\n", ret);
662 		goto out;
663 	}
664 
665 	if (atif->notifications.brightness_change) {
666 		struct drm_encoder *tmp;
667 
668 		/* Find the encoder controlling the brightness */
669 		list_for_each_entry(tmp, &adev->ddev->mode_config.encoder_list,
670 				head) {
671 			struct amdgpu_encoder *enc = to_amdgpu_encoder(tmp);
672 
673 			if ((enc->devices & (ATOM_DEVICE_LCD_SUPPORT)) &&
674 			    enc->enc_priv) {
675 				struct amdgpu_encoder_atom_dig *dig = enc->enc_priv;
676 				if (dig->bl_dev) {
677 					atif->encoder_for_bl = enc;
678 					break;
679 				}
680 			}
681 		}
682 	}
683 
684 	if (atif->functions.sbios_requests && !atif->functions.system_params) {
685 		/* XXX check this workraround, if sbios request function is
686 		 * present we have to see how it's configured in the system
687 		 * params
688 		 */
689 		atif->functions.system_params = true;
690 	}
691 
692 	if (atif->functions.system_params) {
693 		ret = amdgpu_atif_get_notification_params(handle,
694 				&atif->notification_cfg);
695 		if (ret) {
696 			DRM_DEBUG_DRIVER("Call to GET_SYSTEM_PARAMS failed: %d\n",
697 					ret);
698 			/* Disable notification */
699 			atif->notification_cfg.enabled = false;
700 		}
701 	}
702 
703 out:
704 	adev->acpi_nb.notifier_call = amdgpu_acpi_event;
705 	register_acpi_notifier(&adev->acpi_nb);
706 
707 	return ret;
708 }
709 
710 /**
711  * amdgpu_acpi_fini - tear down driver acpi support
712  *
713  * @adev: amdgpu_device pointer
714  *
715  * Unregisters with the acpi notifier chain (all asics).
716  */
717 void amdgpu_acpi_fini(struct amdgpu_device *adev)
718 {
719 	unregister_acpi_notifier(&adev->acpi_nb);
720 }
721