xref: /dflybsd-src/sys/dev/drm/i915/intel_opregion.c (revision 3a48e5e12ec3efb92c37faab0712482a4d0e1529)
1 /*
2  * Copyright 2008 Intel Corporation <hong.liu@intel.com>
3  * Copyright 2008 Red Hat <mjg@redhat.com>
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining
6  * a copy of this software and associated documentation files (the
7  * "Software"), to deal in the Software without restriction, including
8  * without limitation the rights to use, copy, modify, merge, publish,
9  * distribute, sub license, and/or sell copies of the Software, and to
10  * permit persons to whom the Software is furnished to do so, subject to
11  * the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the
14  * next paragraph) shall be included in all copies or substantial
15  * portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20  * NON-INFRINGEMENT.  IN NO EVENT SHALL INTEL AND/OR ITS SUPPLIERS BE
21  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
22  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
24  * SOFTWARE.
25  *
26  */
27 
28 #include <linux/dmi.h>
29 
30 #include <drm/drmP.h>
31 #include <drm/i915_drm.h>
32 #include "i915_drv.h"
33 #include "intel_drv.h"
34 
35 #include <contrib/dev/acpica/source/include/acpi.h>
36 #include <contrib/dev/acpica/source/include/accommon.h>
37 #include <dev/acpica/acpivar.h>
38 
39 #define OPREGION_HEADER_OFFSET 0
40 #define OPREGION_ACPI_OFFSET   0x100
41 #define   ACPI_CLID 0x01ac /* current lid state indicator */
42 #define   ACPI_CDCK 0x01b0 /* current docking state indicator */
43 #define OPREGION_SWSCI_OFFSET  0x200
44 #define OPREGION_ASLE_OFFSET   0x300
45 #define OPREGION_VBT_OFFSET    0x400
46 #define OPREGION_ASLE_EXT_OFFSET	0x1C00
47 
48 #define OPREGION_SIGNATURE "IntelGraphicsMem"
49 #define MBOX_ACPI      (1<<0)
50 #define MBOX_SWSCI     (1<<1)
51 #define MBOX_ASLE      (1<<2)
52 #define MBOX_ASLE_EXT  (1<<4)
53 
54 struct opregion_header {
55 	u8 signature[16];
56 	u32 size;
57 	u32 opregion_ver;
58 	u8 bios_ver[32];
59 	u8 vbios_ver[16];
60 	u8 driver_ver[16];
61 	u32 mboxes;
62 	u32 driver_model;
63 	u32 pcon;
64 	u8 dver[32];
65 	u8 rsvd[124];
66 } __packed;
67 
68 /* OpRegion mailbox #1: public ACPI methods */
69 struct opregion_acpi {
70 	u32 drdy;       /* driver readiness */
71 	u32 csts;       /* notification status */
72 	u32 cevt;       /* current event */
73 	u8 rsvd1[20];
74 	u32 didl[8];    /* supported display devices ID list */
75 	u32 cpdl[8];    /* currently presented display list */
76 	u32 cadl[8];    /* currently active display list */
77 	u32 nadl[8];    /* next active devices list */
78 	u32 aslp;       /* ASL sleep time-out */
79 	u32 tidx;       /* toggle table index */
80 	u32 chpd;       /* current hotplug enable indicator */
81 	u32 clid;       /* current lid state*/
82 	u32 cdck;       /* current docking state */
83 	u32 sxsw;       /* Sx state resume */
84 	u32 evts;       /* ASL supported events */
85 	u32 cnot;       /* current OS notification */
86 	u32 nrdy;       /* driver status */
87 	u32 did2[7];	/* extended supported display devices ID list */
88 	u32 cpd2[7];	/* extended attached display devices list */
89 	u8 rsvd2[4];
90 } __packed;
91 
92 /* OpRegion mailbox #2: SWSCI */
93 struct opregion_swsci {
94 	u32 scic;       /* SWSCI command|status|data */
95 	u32 parm;       /* command parameters */
96 	u32 dslp;       /* driver sleep time-out */
97 	u8 rsvd[244];
98 } __packed;
99 
100 /* OpRegion mailbox #3: ASLE */
101 struct opregion_asle {
102 	u32 ardy;       /* driver readiness */
103 	u32 aslc;       /* ASLE interrupt command */
104 	u32 tche;       /* technology enabled indicator */
105 	u32 alsi;       /* current ALS illuminance reading */
106 	u32 bclp;       /* backlight brightness to set */
107 	u32 pfit;       /* panel fitting state */
108 	u32 cblv;       /* current brightness level */
109 	u16 bclm[20];   /* backlight level duty cycle mapping table */
110 	u32 cpfm;       /* current panel fitting mode */
111 	u32 epfm;       /* enabled panel fitting modes */
112 	u8 plut[74];    /* panel LUT and identifier */
113 	u32 pfmb;       /* PWM freq and min brightness */
114 	u32 cddv;       /* color correction default values */
115 	u32 pcft;       /* power conservation features */
116 	u32 srot;       /* supported rotation angles */
117 	u32 iuer;       /* IUER events */
118 	u64 fdss;
119 	u32 fdsp;
120 	u32 stat;
121 	u64 rvda;	/* Physical address of raw vbt data */
122 	u32 rvds;	/* Size of raw vbt data */
123 	u8 rsvd[58];
124 } __packed;
125 
126 /* OpRegion mailbox #5: ASLE ext */
127 struct opregion_asle_ext {
128 	u32 phed;	/* Panel Header */
129 	u8 bddc[256];	/* Panel EDID */
130 	u8 rsvd[764];
131 } __packed;
132 
133 /* Driver readiness indicator */
134 #define ASLE_ARDY_READY		(1 << 0)
135 #define ASLE_ARDY_NOT_READY	(0 << 0)
136 
137 /* ASLE Interrupt Command (ASLC) bits */
138 #define ASLC_SET_ALS_ILLUM		(1 << 0)
139 #define ASLC_SET_BACKLIGHT		(1 << 1)
140 #define ASLC_SET_PFIT			(1 << 2)
141 #define ASLC_SET_PWM_FREQ		(1 << 3)
142 #define ASLC_SUPPORTED_ROTATION_ANGLES	(1 << 4)
143 #define ASLC_BUTTON_ARRAY		(1 << 5)
144 #define ASLC_CONVERTIBLE_INDICATOR	(1 << 6)
145 #define ASLC_DOCKING_INDICATOR		(1 << 7)
146 #define ASLC_ISCT_STATE_CHANGE		(1 << 8)
147 #define ASLC_REQ_MSK			0x1ff
148 /* response bits */
149 #define ASLC_ALS_ILLUM_FAILED		(1 << 10)
150 #define ASLC_BACKLIGHT_FAILED		(1 << 12)
151 #define ASLC_PFIT_FAILED		(1 << 14)
152 #define ASLC_PWM_FREQ_FAILED		(1 << 16)
153 #define ASLC_ROTATION_ANGLES_FAILED	(1 << 18)
154 #define ASLC_BUTTON_ARRAY_FAILED	(1 << 20)
155 #define ASLC_CONVERTIBLE_FAILED		(1 << 22)
156 #define ASLC_DOCKING_FAILED		(1 << 24)
157 #define ASLC_ISCT_STATE_FAILED		(1 << 26)
158 
159 /* Technology enabled indicator */
160 #define ASLE_TCHE_ALS_EN	(1 << 0)
161 #define ASLE_TCHE_BLC_EN	(1 << 1)
162 #define ASLE_TCHE_PFIT_EN	(1 << 2)
163 #define ASLE_TCHE_PFMB_EN	(1 << 3)
164 
165 /* ASLE backlight brightness to set */
166 #define ASLE_BCLP_VALID                (1<<31)
167 #define ASLE_BCLP_MSK          (~(1<<31))
168 
169 /* ASLE panel fitting request */
170 #define ASLE_PFIT_VALID         (1<<31)
171 #define ASLE_PFIT_CENTER (1<<0)
172 #define ASLE_PFIT_STRETCH_TEXT (1<<1)
173 #define ASLE_PFIT_STRETCH_GFX (1<<2)
174 
175 /* PWM frequency and minimum brightness */
176 #define ASLE_PFMB_BRIGHTNESS_MASK (0xff)
177 #define ASLE_PFMB_BRIGHTNESS_VALID (1<<8)
178 #define ASLE_PFMB_PWM_MASK (0x7ffffe00)
179 #define ASLE_PFMB_PWM_VALID (1<<31)
180 
181 #define ASLE_CBLV_VALID         (1<<31)
182 
183 /* IUER */
184 #define ASLE_IUER_DOCKING		(1 << 7)
185 #define ASLE_IUER_CONVERTIBLE		(1 << 6)
186 #define ASLE_IUER_ROTATION_LOCK_BTN	(1 << 4)
187 #define ASLE_IUER_VOLUME_DOWN_BTN	(1 << 3)
188 #define ASLE_IUER_VOLUME_UP_BTN		(1 << 2)
189 #define ASLE_IUER_WINDOWS_BTN		(1 << 1)
190 #define ASLE_IUER_POWER_BTN		(1 << 0)
191 
192 /* Software System Control Interrupt (SWSCI) */
193 #define SWSCI_SCIC_INDICATOR		(1 << 0)
194 #define SWSCI_SCIC_MAIN_FUNCTION_SHIFT	1
195 #define SWSCI_SCIC_MAIN_FUNCTION_MASK	(0xf << 1)
196 #define SWSCI_SCIC_SUB_FUNCTION_SHIFT	8
197 #define SWSCI_SCIC_SUB_FUNCTION_MASK	(0xff << 8)
198 #define SWSCI_SCIC_EXIT_PARAMETER_SHIFT	8
199 #define SWSCI_SCIC_EXIT_PARAMETER_MASK	(0xff << 8)
200 #define SWSCI_SCIC_EXIT_STATUS_SHIFT	5
201 #define SWSCI_SCIC_EXIT_STATUS_MASK	(7 << 5)
202 #define SWSCI_SCIC_EXIT_STATUS_SUCCESS	1
203 
204 #define SWSCI_FUNCTION_CODE(main, sub) \
205 	((main) << SWSCI_SCIC_MAIN_FUNCTION_SHIFT | \
206 	 (sub) << SWSCI_SCIC_SUB_FUNCTION_SHIFT)
207 
208 /* SWSCI: Get BIOS Data (GBDA) */
209 #define SWSCI_GBDA			4
210 #define SWSCI_GBDA_SUPPORTED_CALLS	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 0)
211 #define SWSCI_GBDA_REQUESTED_CALLBACKS	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 1)
212 #define SWSCI_GBDA_BOOT_DISPLAY_PREF	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 4)
213 #define SWSCI_GBDA_PANEL_DETAILS	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 5)
214 #define SWSCI_GBDA_TV_STANDARD		SWSCI_FUNCTION_CODE(SWSCI_GBDA, 6)
215 #define SWSCI_GBDA_INTERNAL_GRAPHICS	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 7)
216 #define SWSCI_GBDA_SPREAD_SPECTRUM	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 10)
217 
218 /* SWSCI: System BIOS Callbacks (SBCB) */
219 #define SWSCI_SBCB			6
220 #define SWSCI_SBCB_SUPPORTED_CALLBACKS	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 0)
221 #define SWSCI_SBCB_INIT_COMPLETION	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 1)
222 #define SWSCI_SBCB_PRE_HIRES_SET_MODE	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 3)
223 #define SWSCI_SBCB_POST_HIRES_SET_MODE	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 4)
224 #define SWSCI_SBCB_DISPLAY_SWITCH	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 5)
225 #define SWSCI_SBCB_SET_TV_FORMAT	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 6)
226 #define SWSCI_SBCB_ADAPTER_POWER_STATE	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 7)
227 #define SWSCI_SBCB_DISPLAY_POWER_STATE	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 8)
228 #define SWSCI_SBCB_SET_BOOT_DISPLAY	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 9)
229 #define SWSCI_SBCB_SET_PANEL_DETAILS	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 10)
230 #define SWSCI_SBCB_SET_INTERNAL_GFX	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 11)
231 #define SWSCI_SBCB_POST_HIRES_TO_DOS_FS	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 16)
232 #define SWSCI_SBCB_SUSPEND_RESUME	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 17)
233 #define SWSCI_SBCB_SET_SPREAD_SPECTRUM	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 18)
234 #define SWSCI_SBCB_POST_VBE_PM		SWSCI_FUNCTION_CODE(SWSCI_SBCB, 19)
235 #define SWSCI_SBCB_ENABLE_DISABLE_AUDIO	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 21)
236 
237 /*
238  * ACPI Specification, Revision 5.0, Appendix B.3.2 _DOD (Enumerate All Devices
239  * Attached to the Display Adapter).
240  */
241 #define ACPI_DISPLAY_INDEX_SHIFT		0
242 #define ACPI_DISPLAY_INDEX_MASK			(0xf << 0)
243 #define ACPI_DISPLAY_PORT_ATTACHMENT_SHIFT	4
244 #define ACPI_DISPLAY_PORT_ATTACHMENT_MASK	(0xf << 4)
245 #define ACPI_DISPLAY_TYPE_SHIFT			8
246 #define ACPI_DISPLAY_TYPE_MASK			(0xf << 8)
247 #define ACPI_DISPLAY_TYPE_OTHER			(0 << 8)
248 #define ACPI_DISPLAY_TYPE_VGA			(1 << 8)
249 #define ACPI_DISPLAY_TYPE_TV			(2 << 8)
250 #define ACPI_DISPLAY_TYPE_EXTERNAL_DIGITAL	(3 << 8)
251 #define ACPI_DISPLAY_TYPE_INTERNAL_DIGITAL	(4 << 8)
252 #define ACPI_VENDOR_SPECIFIC_SHIFT		12
253 #define ACPI_VENDOR_SPECIFIC_MASK		(0xf << 12)
254 #define ACPI_BIOS_CAN_DETECT			(1 << 16)
255 #define ACPI_DEPENDS_ON_VGA			(1 << 17)
256 #define ACPI_PIPE_ID_SHIFT			18
257 #define ACPI_PIPE_ID_MASK			(7 << 18)
258 #define ACPI_DEVICE_ID_SCHEME			(1 << 31)
259 
260 #define MAX_DSLP	1500
261 
262 static int swsci(struct drm_i915_private *dev_priv,
263 		 u32 function, u32 parm, u32 *parm_out)
264 {
265 	struct opregion_swsci *swsci = dev_priv->opregion.swsci;
266 	struct pci_dev *pdev = dev_priv->drm.pdev;
267 	u32 main_function, sub_function, scic;
268 	u16 swsci_val;
269 	u32 dslp;
270 
271 	if (!swsci)
272 		return -ENODEV;
273 
274 	main_function = (function & SWSCI_SCIC_MAIN_FUNCTION_MASK) >>
275 		SWSCI_SCIC_MAIN_FUNCTION_SHIFT;
276 	sub_function = (function & SWSCI_SCIC_SUB_FUNCTION_MASK) >>
277 		SWSCI_SCIC_SUB_FUNCTION_SHIFT;
278 
279 	/* Check if we can call the function. See swsci_setup for details. */
280 	if (main_function == SWSCI_SBCB) {
281 		if ((dev_priv->opregion.swsci_sbcb_sub_functions &
282 		     (1 << sub_function)) == 0)
283 			return -EINVAL;
284 	} else if (main_function == SWSCI_GBDA) {
285 		if ((dev_priv->opregion.swsci_gbda_sub_functions &
286 		     (1 << sub_function)) == 0)
287 			return -EINVAL;
288 	}
289 
290 	/* Driver sleep timeout in ms. */
291 	dslp = swsci->dslp;
292 	if (!dslp) {
293 		/* The spec says 2ms should be the default, but it's too small
294 		 * for some machines. */
295 		dslp = 50;
296 	} else if (dslp > MAX_DSLP) {
297 		/* Hey bios, trust must be earned. */
298 		DRM_INFO_ONCE("ACPI BIOS requests an excessive sleep of %u ms, "
299 			      "using %u ms instead\n", dslp, MAX_DSLP);
300 		dslp = MAX_DSLP;
301 	}
302 
303 	/* The spec tells us to do this, but we are the only user... */
304 	scic = swsci->scic;
305 	if (scic & SWSCI_SCIC_INDICATOR) {
306 		DRM_DEBUG_DRIVER("SWSCI request already in progress\n");
307 		return -EBUSY;
308 	}
309 
310 	scic = function | SWSCI_SCIC_INDICATOR;
311 
312 	swsci->parm = parm;
313 	swsci->scic = scic;
314 
315 	/* Ensure SCI event is selected and event trigger is cleared. */
316 	pci_read_config_word(pdev, SWSCI, &swsci_val);
317 	if (!(swsci_val & SWSCI_SCISEL) || (swsci_val & SWSCI_GSSCIE)) {
318 		swsci_val |= SWSCI_SCISEL;
319 		swsci_val &= ~SWSCI_GSSCIE;
320 		pci_write_config_word(pdev, SWSCI, swsci_val);
321 	}
322 
323 	/* Use event trigger to tell bios to check the mail. */
324 	swsci_val |= SWSCI_GSSCIE;
325 	pci_write_config_word(pdev, SWSCI, swsci_val);
326 
327 	/* Poll for the result. */
328 #define C (((scic = swsci->scic) & SWSCI_SCIC_INDICATOR) == 0)
329 	if (wait_for(C, dslp)) {
330 		DRM_DEBUG_DRIVER("SWSCI request timed out\n");
331 		return -ETIMEDOUT;
332 	}
333 
334 	scic = (scic & SWSCI_SCIC_EXIT_STATUS_MASK) >>
335 		SWSCI_SCIC_EXIT_STATUS_SHIFT;
336 
337 	/* Note: scic == 0 is an error! */
338 	if (scic != SWSCI_SCIC_EXIT_STATUS_SUCCESS) {
339 		DRM_DEBUG_DRIVER("SWSCI request error %u\n", scic);
340 		return -EIO;
341 	}
342 
343 	if (parm_out)
344 		*parm_out = swsci->parm;
345 
346 	return 0;
347 
348 #undef C
349 }
350 
351 #define DISPLAY_TYPE_CRT			0
352 #define DISPLAY_TYPE_TV				1
353 #define DISPLAY_TYPE_EXTERNAL_FLAT_PANEL	2
354 #define DISPLAY_TYPE_INTERNAL_FLAT_PANEL	3
355 
356 int intel_opregion_notify_encoder(struct intel_encoder *intel_encoder,
357 				  bool enable)
358 {
359 	struct drm_i915_private *dev_priv = to_i915(intel_encoder->base.dev);
360 	u32 parm = 0;
361 	u32 type = 0;
362 	u32 port;
363 
364 	/* don't care about old stuff for now */
365 	if (!HAS_DDI(dev_priv))
366 		return 0;
367 
368 	if (intel_encoder->type == INTEL_OUTPUT_DSI)
369 		port = 0;
370 	else
371 		port = intel_ddi_get_encoder_port(intel_encoder);
372 
373 	if (port == PORT_E)  {
374 		port = 0;
375 	} else {
376 		parm |= 1 << port;
377 		port++;
378 	}
379 
380 	if (!enable)
381 		parm |= 4 << 8;
382 
383 	switch (intel_encoder->type) {
384 	case INTEL_OUTPUT_ANALOG:
385 		type = DISPLAY_TYPE_CRT;
386 		break;
387 	case INTEL_OUTPUT_UNKNOWN:
388 	case INTEL_OUTPUT_DP:
389 	case INTEL_OUTPUT_HDMI:
390 	case INTEL_OUTPUT_DP_MST:
391 		type = DISPLAY_TYPE_EXTERNAL_FLAT_PANEL;
392 		break;
393 	case INTEL_OUTPUT_EDP:
394 	case INTEL_OUTPUT_DSI:
395 		type = DISPLAY_TYPE_INTERNAL_FLAT_PANEL;
396 		break;
397 	default:
398 		WARN_ONCE(1, "unsupported intel_encoder type %d\n",
399 			  intel_encoder->type);
400 		return -EINVAL;
401 	}
402 
403 	parm |= type << (16 + port * 3);
404 
405 	return swsci(dev_priv, SWSCI_SBCB_DISPLAY_POWER_STATE, parm, NULL);
406 }
407 
408 static const struct {
409 	pci_power_t pci_power_state;
410 	u32 parm;
411 } power_state_map[] = {
412 	{ PCI_D0,	0x00 },
413 	{ PCI_D1,	0x01 },
414 	{ PCI_D2,	0x02 },
415 	{ PCI_D3hot,	0x04 },
416 	{ PCI_D3cold,	0x04 },
417 };
418 
419 int intel_opregion_notify_adapter(struct drm_i915_private *dev_priv,
420 				  pci_power_t state)
421 {
422 	int i;
423 
424 	if (!HAS_DDI(dev_priv))
425 		return 0;
426 
427 	for (i = 0; i < ARRAY_SIZE(power_state_map); i++) {
428 		if (state == power_state_map[i].pci_power_state)
429 			return swsci(dev_priv, SWSCI_SBCB_ADAPTER_POWER_STATE,
430 				     power_state_map[i].parm, NULL);
431 	}
432 
433 	return -EINVAL;
434 }
435 
436 static u32 asle_set_backlight(struct drm_i915_private *dev_priv, u32 bclp)
437 {
438 	struct intel_connector *connector;
439 	struct drm_connector_list_iter conn_iter;
440 	struct opregion_asle *asle = dev_priv->opregion.asle;
441 	struct drm_device *dev = &dev_priv->drm;
442 
443 	DRM_DEBUG_DRIVER("bclp = 0x%08x\n", bclp);
444 
445 #ifndef __DragonFly__
446 	if (acpi_video_get_backlight_type() == acpi_backlight_native) {
447 		DRM_DEBUG_KMS("opregion backlight request ignored\n");
448 		return 0;
449 	}
450 #endif
451 
452 	if (!(bclp & ASLE_BCLP_VALID))
453 		return ASLC_BACKLIGHT_FAILED;
454 
455 	bclp &= ASLE_BCLP_MSK;
456 	if (bclp > 255)
457 		return ASLC_BACKLIGHT_FAILED;
458 
459 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
460 
461 	/*
462 	 * Update backlight on all connectors that support backlight (usually
463 	 * only one).
464 	 */
465 	DRM_DEBUG_KMS("updating opregion backlight %d/255\n", bclp);
466 	drm_connector_list_iter_begin(dev, &conn_iter);
467 	for_each_intel_connector_iter(connector, &conn_iter)
468 		intel_panel_set_backlight_acpi(connector, bclp, 255);
469 	drm_connector_list_iter_end(&conn_iter);
470 	asle->cblv = DIV_ROUND_UP(bclp * 100, 255) | ASLE_CBLV_VALID;
471 
472 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
473 
474 
475 	return 0;
476 }
477 
478 static u32 asle_set_als_illum(struct drm_i915_private *dev_priv, u32 alsi)
479 {
480 	/* alsi is the current ALS reading in lux. 0 indicates below sensor
481 	   range, 0xffff indicates above sensor range. 1-0xfffe are valid */
482 	DRM_DEBUG_DRIVER("Illum is not supported\n");
483 	return ASLC_ALS_ILLUM_FAILED;
484 }
485 
486 static u32 asle_set_pwm_freq(struct drm_i915_private *dev_priv, u32 pfmb)
487 {
488 	DRM_DEBUG_DRIVER("PWM freq is not supported\n");
489 	return ASLC_PWM_FREQ_FAILED;
490 }
491 
492 static u32 asle_set_pfit(struct drm_i915_private *dev_priv, u32 pfit)
493 {
494 	/* Panel fitting is currently controlled by the X code, so this is a
495 	   noop until modesetting support works fully */
496 	DRM_DEBUG_DRIVER("Pfit is not supported\n");
497 	return ASLC_PFIT_FAILED;
498 }
499 
500 static u32 asle_set_supported_rotation_angles(struct drm_i915_private *dev_priv, u32 srot)
501 {
502 	DRM_DEBUG_DRIVER("SROT is not supported\n");
503 	return ASLC_ROTATION_ANGLES_FAILED;
504 }
505 
506 static u32 asle_set_button_array(struct drm_i915_private *dev_priv, u32 iuer)
507 {
508 	if (!iuer)
509 		DRM_DEBUG_DRIVER("Button array event is not supported (nothing)\n");
510 	if (iuer & ASLE_IUER_ROTATION_LOCK_BTN)
511 		DRM_DEBUG_DRIVER("Button array event is not supported (rotation lock)\n");
512 	if (iuer & ASLE_IUER_VOLUME_DOWN_BTN)
513 		DRM_DEBUG_DRIVER("Button array event is not supported (volume down)\n");
514 	if (iuer & ASLE_IUER_VOLUME_UP_BTN)
515 		DRM_DEBUG_DRIVER("Button array event is not supported (volume up)\n");
516 	if (iuer & ASLE_IUER_WINDOWS_BTN)
517 		DRM_DEBUG_DRIVER("Button array event is not supported (windows)\n");
518 	if (iuer & ASLE_IUER_POWER_BTN)
519 		DRM_DEBUG_DRIVER("Button array event is not supported (power)\n");
520 
521 	return ASLC_BUTTON_ARRAY_FAILED;
522 }
523 
524 static u32 asle_set_convertible(struct drm_i915_private *dev_priv, u32 iuer)
525 {
526 	if (iuer & ASLE_IUER_CONVERTIBLE)
527 		DRM_DEBUG_DRIVER("Convertible is not supported (clamshell)\n");
528 	else
529 		DRM_DEBUG_DRIVER("Convertible is not supported (slate)\n");
530 
531 	return ASLC_CONVERTIBLE_FAILED;
532 }
533 
534 static u32 asle_set_docking(struct drm_i915_private *dev_priv, u32 iuer)
535 {
536 	if (iuer & ASLE_IUER_DOCKING)
537 		DRM_DEBUG_DRIVER("Docking is not supported (docked)\n");
538 	else
539 		DRM_DEBUG_DRIVER("Docking is not supported (undocked)\n");
540 
541 	return ASLC_DOCKING_FAILED;
542 }
543 
544 static u32 asle_isct_state(struct drm_i915_private *dev_priv)
545 {
546 	DRM_DEBUG_DRIVER("ISCT is not supported\n");
547 	return ASLC_ISCT_STATE_FAILED;
548 }
549 
550 static void asle_work(struct work_struct *work)
551 {
552 	struct intel_opregion *opregion =
553 		container_of(work, struct intel_opregion, asle_work);
554 	struct drm_i915_private *dev_priv =
555 		container_of(opregion, struct drm_i915_private, opregion);
556 	struct opregion_asle *asle = dev_priv->opregion.asle;
557 	u32 aslc_stat = 0;
558 	u32 aslc_req;
559 
560 	if (!asle)
561 		return;
562 
563 	aslc_req = asle->aslc;
564 
565 	if (!(aslc_req & ASLC_REQ_MSK)) {
566 		DRM_DEBUG_DRIVER("No request on ASLC interrupt 0x%08x\n",
567 				 aslc_req);
568 		return;
569 	}
570 
571 	if (aslc_req & ASLC_SET_ALS_ILLUM)
572 		aslc_stat |= asle_set_als_illum(dev_priv, asle->alsi);
573 
574 	if (aslc_req & ASLC_SET_BACKLIGHT)
575 		aslc_stat |= asle_set_backlight(dev_priv, asle->bclp);
576 
577 	if (aslc_req & ASLC_SET_PFIT)
578 		aslc_stat |= asle_set_pfit(dev_priv, asle->pfit);
579 
580 	if (aslc_req & ASLC_SET_PWM_FREQ)
581 		aslc_stat |= asle_set_pwm_freq(dev_priv, asle->pfmb);
582 
583 	if (aslc_req & ASLC_SUPPORTED_ROTATION_ANGLES)
584 		aslc_stat |= asle_set_supported_rotation_angles(dev_priv,
585 							asle->srot);
586 
587 	if (aslc_req & ASLC_BUTTON_ARRAY)
588 		aslc_stat |= asle_set_button_array(dev_priv, asle->iuer);
589 
590 	if (aslc_req & ASLC_CONVERTIBLE_INDICATOR)
591 		aslc_stat |= asle_set_convertible(dev_priv, asle->iuer);
592 
593 	if (aslc_req & ASLC_DOCKING_INDICATOR)
594 		aslc_stat |= asle_set_docking(dev_priv, asle->iuer);
595 
596 	if (aslc_req & ASLC_ISCT_STATE_CHANGE)
597 		aslc_stat |= asle_isct_state(dev_priv);
598 
599 	asle->aslc = aslc_stat;
600 }
601 
602 void intel_opregion_asle_intr(struct drm_i915_private *dev_priv)
603 {
604 	if (dev_priv->opregion.asle)
605 		schedule_work(&dev_priv->opregion.asle_work);
606 }
607 
608 #define ACPI_EV_DISPLAY_SWITCH (1<<0)
609 #define ACPI_EV_LID            (1<<1)
610 #define ACPI_EV_DOCK           (1<<2)
611 
612 static struct intel_opregion *system_opregion;
613 
614 #if 0
615 static int intel_opregion_video_event(struct notifier_block *nb,
616 				      unsigned long val, void *data)
617 {
618 	/* The only video events relevant to opregion are 0x80. These indicate
619 	   either a docking event, lid switch or display switch request. In
620 	   Linux, these are handled by the dock, button and video drivers.
621 	*/
622 
623 	struct acpi_bus_event *event = data;
624 	struct opregion_acpi *acpi;
625 	int ret = NOTIFY_OK;
626 
627 	if (strcmp(event->device_class, ACPI_VIDEO_CLASS) != 0)
628 		return NOTIFY_DONE;
629 
630 	if (!system_opregion)
631 		return NOTIFY_DONE;
632 
633 	acpi = system_opregion->acpi;
634 
635 	if (event->type == 0x80 && ((acpi->cevt & 1) == 0))
636 		ret = NOTIFY_BAD;
637 
638 	acpi->csts = 0;
639 
640 	return ret;
641 }
642 
643 static struct notifier_block intel_opregion_notifier = {
644 	.notifier_call = intel_opregion_video_event,
645 };
646 #endif
647 
648 /*
649  * Initialise the DIDL field in opregion. This passes a list of devices to
650  * the firmware. Values are defined by section B.4.2 of the ACPI specification
651  * (version 3)
652  */
653 
654 static void set_did(struct intel_opregion *opregion, int i, u32 val)
655 {
656 	if (i < ARRAY_SIZE(opregion->acpi->didl)) {
657 		opregion->acpi->didl[i] = val;
658 	} else {
659 		i -= ARRAY_SIZE(opregion->acpi->didl);
660 
661 		if (WARN_ON(i >= ARRAY_SIZE(opregion->acpi->did2)))
662 			return;
663 
664 		opregion->acpi->did2[i] = val;
665 	}
666 }
667 
668 static u32 acpi_display_type(struct intel_connector *connector)
669 {
670 	u32 display_type;
671 
672 	switch (connector->base.connector_type) {
673 	case DRM_MODE_CONNECTOR_VGA:
674 	case DRM_MODE_CONNECTOR_DVIA:
675 		display_type = ACPI_DISPLAY_TYPE_VGA;
676 		break;
677 	case DRM_MODE_CONNECTOR_Composite:
678 	case DRM_MODE_CONNECTOR_SVIDEO:
679 	case DRM_MODE_CONNECTOR_Component:
680 	case DRM_MODE_CONNECTOR_9PinDIN:
681 	case DRM_MODE_CONNECTOR_TV:
682 		display_type = ACPI_DISPLAY_TYPE_TV;
683 		break;
684 	case DRM_MODE_CONNECTOR_DVII:
685 	case DRM_MODE_CONNECTOR_DVID:
686 	case DRM_MODE_CONNECTOR_DisplayPort:
687 	case DRM_MODE_CONNECTOR_HDMIA:
688 	case DRM_MODE_CONNECTOR_HDMIB:
689 		display_type = ACPI_DISPLAY_TYPE_EXTERNAL_DIGITAL;
690 		break;
691 	case DRM_MODE_CONNECTOR_LVDS:
692 	case DRM_MODE_CONNECTOR_eDP:
693 	case DRM_MODE_CONNECTOR_DSI:
694 		display_type = ACPI_DISPLAY_TYPE_INTERNAL_DIGITAL;
695 		break;
696 	case DRM_MODE_CONNECTOR_Unknown:
697 	case DRM_MODE_CONNECTOR_VIRTUAL:
698 		display_type = ACPI_DISPLAY_TYPE_OTHER;
699 		break;
700 	default:
701 		MISSING_CASE(connector->base.connector_type);
702 		display_type = ACPI_DISPLAY_TYPE_OTHER;
703 		break;
704 	}
705 
706 	return display_type;
707 }
708 
709 static void intel_didl_outputs(struct drm_i915_private *dev_priv)
710 {
711 	struct intel_opregion *opregion = &dev_priv->opregion;
712 	struct intel_connector *connector;
713 	struct drm_connector_list_iter conn_iter;
714 	int i = 0, max_outputs;
715 	int display_index[16] = {};
716 
717 	/*
718 	 * In theory, did2, the extended didl, gets added at opregion version
719 	 * 3.0. In practice, however, we're supposed to set it for earlier
720 	 * versions as well, since a BIOS that doesn't understand did2 should
721 	 * not look at it anyway. Use a variable so we can tweak this if a need
722 	 * arises later.
723 	 */
724 	max_outputs = ARRAY_SIZE(opregion->acpi->didl) +
725 		ARRAY_SIZE(opregion->acpi->did2);
726 
727 	drm_connector_list_iter_begin(&dev_priv->drm, &conn_iter);
728 	for_each_intel_connector_iter(connector, &conn_iter) {
729 		u32 device_id, type;
730 
731 		device_id = acpi_display_type(connector);
732 
733 		/* Use display type specific display index. */
734 		type = (device_id & ACPI_DISPLAY_TYPE_MASK)
735 			>> ACPI_DISPLAY_TYPE_SHIFT;
736 		device_id |= display_index[type]++ << ACPI_DISPLAY_INDEX_SHIFT;
737 
738 		connector->acpi_device_id = device_id;
739 		if (i < max_outputs)
740 			set_did(opregion, i, device_id);
741 		i++;
742 	}
743 	drm_connector_list_iter_end(&conn_iter);
744 
745 	DRM_DEBUG_KMS("%d outputs detected\n", i);
746 
747 	if (i > max_outputs)
748 		DRM_ERROR("More than %d outputs in connector list\n",
749 			  max_outputs);
750 
751 	/* If fewer than max outputs, the list must be null terminated */
752 	if (i < max_outputs)
753 		set_did(opregion, i, 0);
754 }
755 
756 static void intel_setup_cadls(struct drm_i915_private *dev_priv)
757 {
758 	struct intel_opregion *opregion = &dev_priv->opregion;
759 	struct intel_connector *connector;
760 	struct drm_connector_list_iter conn_iter;
761 	int i = 0;
762 
763 	/*
764 	 * Initialize the CADL field from the connector device ids. This is
765 	 * essentially the same as copying from the DIDL. Technically, this is
766 	 * not always correct as display outputs may exist, but not active. This
767 	 * initialization is necessary for some Clevo laptops that check this
768 	 * field before processing the brightness and display switching hotkeys.
769 	 *
770 	 * Note that internal panels should be at the front of the connector
771 	 * list already, ensuring they're not left out.
772 	 */
773 	drm_connector_list_iter_begin(&dev_priv->drm, &conn_iter);
774 	for_each_intel_connector_iter(connector, &conn_iter) {
775 		if (i >= ARRAY_SIZE(opregion->acpi->cadl))
776 			break;
777 		opregion->acpi->cadl[i++] = connector->acpi_device_id;
778 	}
779 	drm_connector_list_iter_end(&conn_iter);
780 
781 	/* If fewer than 8 active devices, the list must be null terminated */
782 	if (i < ARRAY_SIZE(opregion->acpi->cadl))
783 		opregion->acpi->cadl[i] = 0;
784 }
785 
786 void intel_opregion_register(struct drm_i915_private *dev_priv)
787 {
788 	struct intel_opregion *opregion = &dev_priv->opregion;
789 
790 	if (!opregion->header)
791 		return;
792 
793 	if (opregion->acpi) {
794 		intel_didl_outputs(dev_priv);
795 		intel_setup_cadls(dev_priv);
796 
797 		/* Notify BIOS we are ready to handle ACPI video ext notifs.
798 		 * Right now, all the events are handled by the ACPI video module.
799 		 * We don't actually need to do anything with them. */
800 		opregion->acpi->csts = 0;
801 		opregion->acpi->drdy = 1;
802 
803 		system_opregion = opregion;
804 	}
805 
806 	if (opregion->asle) {
807 		opregion->asle->tche = ASLE_TCHE_BLC_EN;
808 		opregion->asle->ardy = ASLE_ARDY_READY;
809 	}
810 }
811 
812 void intel_opregion_unregister(struct drm_i915_private *dev_priv)
813 {
814 	struct intel_opregion *opregion = &dev_priv->opregion;
815 
816 	if (!opregion->header)
817 		return;
818 
819 	if (opregion->asle)
820 		opregion->asle->ardy = ASLE_ARDY_NOT_READY;
821 
822 	cancel_work_sync(&dev_priv->opregion.asle_work);
823 
824 	if (opregion->acpi) {
825 		opregion->acpi->drdy = 0;
826 
827 		system_opregion = NULL;
828 	}
829 
830 	/* just clear all opregion memory pointers now */
831 	iounmap(opregion->header);
832 	if (opregion->rvda) {
833 		iounmap(opregion->rvda);
834 		opregion->rvda = NULL;
835 	}
836 	opregion->header = NULL;
837 	opregion->acpi = NULL;
838 	opregion->swsci = NULL;
839 	opregion->asle = NULL;
840 	opregion->vbt = NULL;
841 	opregion->lid_state = NULL;
842 }
843 
844 static void swsci_setup(struct drm_i915_private *dev_priv)
845 {
846 	struct intel_opregion *opregion = &dev_priv->opregion;
847 	bool requested_callbacks = false;
848 	u32 tmp;
849 
850 	/* Sub-function code 0 is okay, let's allow them. */
851 	opregion->swsci_gbda_sub_functions = 1;
852 	opregion->swsci_sbcb_sub_functions = 1;
853 
854 	/* We use GBDA to ask for supported GBDA calls. */
855 	if (swsci(dev_priv, SWSCI_GBDA_SUPPORTED_CALLS, 0, &tmp) == 0) {
856 		/* make the bits match the sub-function codes */
857 		tmp <<= 1;
858 		opregion->swsci_gbda_sub_functions |= tmp;
859 	}
860 
861 	/*
862 	 * We also use GBDA to ask for _requested_ SBCB callbacks. The driver
863 	 * must not call interfaces that are not specifically requested by the
864 	 * bios.
865 	 */
866 	if (swsci(dev_priv, SWSCI_GBDA_REQUESTED_CALLBACKS, 0, &tmp) == 0) {
867 		/* here, the bits already match sub-function codes */
868 		opregion->swsci_sbcb_sub_functions |= tmp;
869 		requested_callbacks = true;
870 	}
871 
872 	/*
873 	 * But we use SBCB to ask for _supported_ SBCB calls. This does not mean
874 	 * the callback is _requested_. But we still can't call interfaces that
875 	 * are not requested.
876 	 */
877 	if (swsci(dev_priv, SWSCI_SBCB_SUPPORTED_CALLBACKS, 0, &tmp) == 0) {
878 		/* make the bits match the sub-function codes */
879 		u32 low = tmp & 0x7ff;
880 		u32 high = tmp & ~0xfff; /* bit 11 is reserved */
881 		tmp = (high << 4) | (low << 1) | 1;
882 
883 		/* best guess what to do with supported wrt requested */
884 		if (requested_callbacks) {
885 			u32 req = opregion->swsci_sbcb_sub_functions;
886 			if ((req & tmp) != req)
887 				DRM_DEBUG_DRIVER("SWSCI BIOS requested (%08x) SBCB callbacks that are not supported (%08x)\n", req, tmp);
888 			/* XXX: for now, trust the requested callbacks */
889 			/* opregion->swsci_sbcb_sub_functions &= tmp; */
890 		} else {
891 			opregion->swsci_sbcb_sub_functions |= tmp;
892 		}
893 	}
894 
895 	DRM_DEBUG_DRIVER("SWSCI GBDA callbacks %08x, SBCB callbacks %08x\n",
896 			 opregion->swsci_gbda_sub_functions,
897 			 opregion->swsci_sbcb_sub_functions);
898 }
899 
900 static int intel_no_opregion_vbt_callback(const struct dmi_system_id *id)
901 {
902 	DRM_DEBUG_KMS("Falling back to manually reading VBT from "
903 		      "VBIOS ROM for %s\n", id->ident);
904 	return 1;
905 }
906 
907 static const struct dmi_system_id intel_no_opregion_vbt[] = {
908 	{
909 		.callback = intel_no_opregion_vbt_callback,
910 		.ident = "ThinkCentre A57",
911 		.matches = {
912 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
913 			DMI_MATCH(DMI_PRODUCT_NAME, "97027RG"),
914 		},
915 	},
916 	{ }
917 };
918 
919 int intel_opregion_setup(struct drm_i915_private *dev_priv)
920 {
921 	struct intel_opregion *opregion = &dev_priv->opregion;
922 	struct pci_dev *pdev = dev_priv->drm.pdev;
923 	u32 asls, mboxes;
924 	char buf[sizeof(OPREGION_SIGNATURE)];
925 	int err = 0;
926 	void *base;
927 	const void *vbt;
928 	u32 vbt_size;
929 
930 	BUILD_BUG_ON(sizeof(struct opregion_header) != 0x100);
931 	BUILD_BUG_ON(sizeof(struct opregion_acpi) != 0x100);
932 	BUILD_BUG_ON(sizeof(struct opregion_swsci) != 0x100);
933 	BUILD_BUG_ON(sizeof(struct opregion_asle) != 0x100);
934 	BUILD_BUG_ON(sizeof(struct opregion_asle_ext) != 0x400);
935 
936 	pci_read_config_dword(pdev, ASLS, &asls);
937 	DRM_DEBUG_DRIVER("graphic opregion physical addr: 0x%x\n", asls);
938 	if (asls == 0) {
939 		DRM_DEBUG_DRIVER("ACPI OpRegion not supported!\n");
940 		return -ENOTSUPP;
941 	}
942 
943 	INIT_WORK(&opregion->asle_work, asle_work);
944 
945 	base = (void *)pmap_mapbios(asls, OPREGION_SIZE);
946 	if (!base)
947 		return -ENOMEM;
948 
949 	memcpy(buf, base, sizeof(buf));
950 
951 	if (memcmp(buf, OPREGION_SIGNATURE, 16)) {
952 		DRM_DEBUG_DRIVER("opregion signature mismatch\n");
953 		err = -EINVAL;
954 		goto err_out;
955 	}
956 	opregion->header = base;
957 	opregion->lid_state = base + ACPI_CLID;
958 
959 	mboxes = opregion->header->mboxes;
960 	if (mboxes & MBOX_ACPI) {
961 		DRM_DEBUG_DRIVER("Public ACPI methods supported\n");
962 		opregion->acpi = base + OPREGION_ACPI_OFFSET;
963 	}
964 
965 	if (mboxes & MBOX_SWSCI) {
966 		DRM_DEBUG_DRIVER("SWSCI supported\n");
967 		opregion->swsci = base + OPREGION_SWSCI_OFFSET;
968 		swsci_setup(dev_priv);
969 	}
970 
971 	if (mboxes & MBOX_ASLE) {
972 		DRM_DEBUG_DRIVER("ASLE supported\n");
973 		opregion->asle = base + OPREGION_ASLE_OFFSET;
974 
975 		opregion->asle->ardy = ASLE_ARDY_NOT_READY;
976 	}
977 
978 	if (mboxes & MBOX_ASLE_EXT)
979 		DRM_DEBUG_DRIVER("ASLE extension supported\n");
980 
981 	if (dmi_check_system(intel_no_opregion_vbt))
982 		goto out;
983 
984 	if (opregion->header->opregion_ver >= 2 && opregion->asle &&
985 	    opregion->asle->rvda && opregion->asle->rvds) {
986 		opregion->rvda = pmap_mapbios(opregion->asle->rvda,
987 					  opregion->asle->rvds);
988 		vbt = opregion->rvda;
989 		vbt_size = opregion->asle->rvds;
990 		if (intel_bios_is_valid_vbt(vbt, vbt_size)) {
991 			DRM_DEBUG_KMS("Found valid VBT in ACPI OpRegion (RVDA)\n");
992 			opregion->vbt = vbt;
993 			opregion->vbt_size = vbt_size;
994 			goto out;
995 		} else {
996 			DRM_DEBUG_KMS("Invalid VBT in ACPI OpRegion (RVDA)\n");
997 		}
998 	}
999 
1000 	vbt = base + OPREGION_VBT_OFFSET;
1001 	/*
1002 	 * The VBT specification says that if the ASLE ext mailbox is not used
1003 	 * its area is reserved, but on some CHT boards the VBT extends into the
1004 	 * ASLE ext area. Allow this even though it is against the spec, so we
1005 	 * do not end up rejecting the VBT on those boards (and end up not
1006 	 * finding the LCD panel because of this).
1007 	 */
1008 	vbt_size = (mboxes & MBOX_ASLE_EXT) ?
1009 		OPREGION_ASLE_EXT_OFFSET : OPREGION_SIZE;
1010 	vbt_size -= OPREGION_VBT_OFFSET;
1011 	if (intel_bios_is_valid_vbt(vbt, vbt_size)) {
1012 		DRM_DEBUG_KMS("Found valid VBT in ACPI OpRegion (Mailbox #4)\n");
1013 		opregion->vbt = vbt;
1014 		opregion->vbt_size = vbt_size;
1015 	} else {
1016 		DRM_DEBUG_KMS("Invalid VBT in ACPI OpRegion (Mailbox #4)\n");
1017 	}
1018 
1019 out:
1020 	return 0;
1021 
1022 err_out:
1023 	iounmap(base);
1024 	return err;
1025 }
1026 
1027 static int intel_use_opregion_panel_type_callback(const struct dmi_system_id *id)
1028 {
1029 	DRM_INFO("Using panel type from OpRegion on %s\n", id->ident);
1030 	return 1;
1031 }
1032 
1033 static const struct dmi_system_id intel_use_opregion_panel_type[] = {
1034 	{
1035 		.callback = intel_use_opregion_panel_type_callback,
1036 		.ident = "Conrac GmbH IX45GM2",
1037 		.matches = {DMI_MATCH(DMI_SYS_VENDOR, "Conrac GmbH"),
1038 			    DMI_MATCH(DMI_PRODUCT_NAME, "IX45GM2"),
1039 		},
1040 	},
1041 	{ }
1042 };
1043 
1044 int
1045 intel_opregion_get_panel_type(struct drm_i915_private *dev_priv)
1046 {
1047 	u32 panel_details;
1048 	int ret;
1049 
1050 	ret = swsci(dev_priv, SWSCI_GBDA_PANEL_DETAILS, 0x0, &panel_details);
1051 	if (ret) {
1052 		DRM_DEBUG_KMS("Failed to get panel details from OpRegion (%d)\n",
1053 			      ret);
1054 		return ret;
1055 	}
1056 
1057 	ret = (panel_details >> 8) & 0xff;
1058 	if (ret > 0x10) {
1059 		DRM_DEBUG_KMS("Invalid OpRegion panel type 0x%x\n", ret);
1060 		return -EINVAL;
1061 	}
1062 
1063 	/* fall back to VBT panel type? */
1064 	if (ret == 0x0) {
1065 		DRM_DEBUG_KMS("No panel type in OpRegion\n");
1066 		return -ENODEV;
1067 	}
1068 
1069 	/*
1070 	 * So far we know that some machined must use it, others must not use it.
1071 	 * There doesn't seem to be any way to determine which way to go, except
1072 	 * via a quirk list :(
1073 	 */
1074 	if (!dmi_check_system(intel_use_opregion_panel_type)) {
1075 		DRM_DEBUG_KMS("Ignoring OpRegion panel type (%d)\n", ret - 1);
1076 		return -ENODEV;
1077 	}
1078 
1079 	return ret - 1;
1080 }
1081