xref: /dragonfly/sys/dev/drm/i915/intel_lvds.c (revision 2b57e6df)
1 /*
2  * Copyright © 2006-2007 Intel Corporation
3  * Copyright (c) 2006 Dave Airlie <airlied@linux.ie>
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the next
13  * paragraph) shall be included in all copies or substantial portions of the
14  * Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22  * DEALINGS IN THE SOFTWARE.
23  *
24  * Authors:
25  *	Eric Anholt <eric@anholt.net>
26  *      Dave Airlie <airlied@linux.ie>
27  *      Jesse Barnes <jesse.barnes@intel.com>
28  */
29 
30 #include "opt_drm.h"
31 
32 #include <linux/dmi.h>
33 #include <linux/i2c.h>
34 #include <linux/slab.h>
35 #include <linux/vga_switcheroo.h>
36 #include <drm/drmP.h>
37 #include <drm/drm_atomic_helper.h>
38 #include <drm/drm_crtc.h>
39 #include <drm/drm_edid.h>
40 #include "intel_drv.h"
41 #include <drm/i915_drm.h>
42 #include "i915_drv.h"
43 #include <linux/acpi.h>
44 
45 /* Private structure for the integrated LVDS support */
46 struct intel_lvds_connector {
47 	struct intel_connector base;
48 
49 	struct notifier_block lid_notifier;
50 };
51 
52 struct intel_lvds_pps {
53 	/* 100us units */
54 	int t1_t2;
55 	int t3;
56 	int t4;
57 	int t5;
58 	int tx;
59 
60 	int divider;
61 
62 	int port;
63 	bool powerdown_on_reset;
64 };
65 
66 struct intel_lvds_encoder {
67 	struct intel_encoder base;
68 
69 	bool is_dual_link;
70 	i915_reg_t reg;
71 	u32 a3_power;
72 
73 	struct intel_lvds_pps init_pps;
74 	u32 init_lvds_val;
75 
76 	struct intel_lvds_connector *attached_connector;
77 };
78 
79 static struct intel_lvds_encoder *to_lvds_encoder(struct drm_encoder *encoder)
80 {
81 	return container_of(encoder, struct intel_lvds_encoder, base.base);
82 }
83 
84 static struct intel_lvds_connector *to_lvds_connector(struct drm_connector *connector)
85 {
86 	return container_of(connector, struct intel_lvds_connector, base.base);
87 }
88 
89 static bool intel_lvds_get_hw_state(struct intel_encoder *encoder,
90 				    enum i915_pipe *pipe)
91 {
92 	struct drm_device *dev = encoder->base.dev;
93 	struct drm_i915_private *dev_priv = to_i915(dev);
94 	struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
95 	u32 tmp;
96 	bool ret;
97 
98 	if (!intel_display_power_get_if_enabled(dev_priv,
99 						encoder->power_domain))
100 		return false;
101 
102 	ret = false;
103 
104 	tmp = I915_READ(lvds_encoder->reg);
105 
106 	if (!(tmp & LVDS_PORT_EN))
107 		goto out;
108 
109 	if (HAS_PCH_CPT(dev_priv))
110 		*pipe = PORT_TO_PIPE_CPT(tmp);
111 	else
112 		*pipe = PORT_TO_PIPE(tmp);
113 
114 	ret = true;
115 
116 out:
117 	intel_display_power_put(dev_priv, encoder->power_domain);
118 
119 	return ret;
120 }
121 
122 static void intel_lvds_get_config(struct intel_encoder *encoder,
123 				  struct intel_crtc_state *pipe_config)
124 {
125 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
126 	struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
127 	u32 tmp, flags = 0;
128 
129 	tmp = I915_READ(lvds_encoder->reg);
130 	if (tmp & LVDS_HSYNC_POLARITY)
131 		flags |= DRM_MODE_FLAG_NHSYNC;
132 	else
133 		flags |= DRM_MODE_FLAG_PHSYNC;
134 	if (tmp & LVDS_VSYNC_POLARITY)
135 		flags |= DRM_MODE_FLAG_NVSYNC;
136 	else
137 		flags |= DRM_MODE_FLAG_PVSYNC;
138 
139 	pipe_config->base.adjusted_mode.flags |= flags;
140 
141 	if (INTEL_GEN(dev_priv) < 5)
142 		pipe_config->gmch_pfit.lvds_border_bits =
143 			tmp & LVDS_BORDER_ENABLE;
144 
145 	/* gen2/3 store dither state in pfit control, needs to match */
146 	if (INTEL_GEN(dev_priv) < 4) {
147 		tmp = I915_READ(PFIT_CONTROL);
148 
149 		pipe_config->gmch_pfit.control |= tmp & PANEL_8TO6_DITHER_ENABLE;
150 	}
151 
152 	pipe_config->base.adjusted_mode.crtc_clock = pipe_config->port_clock;
153 }
154 
155 static void intel_lvds_pps_get_hw_state(struct drm_i915_private *dev_priv,
156 					struct intel_lvds_pps *pps)
157 {
158 	u32 val;
159 
160 	pps->powerdown_on_reset = I915_READ(PP_CONTROL(0)) & PANEL_POWER_RESET;
161 
162 	val = I915_READ(PP_ON_DELAYS(0));
163 	pps->port = (val & PANEL_PORT_SELECT_MASK) >>
164 		    PANEL_PORT_SELECT_SHIFT;
165 	pps->t1_t2 = (val & PANEL_POWER_UP_DELAY_MASK) >>
166 		     PANEL_POWER_UP_DELAY_SHIFT;
167 	pps->t5 = (val & PANEL_LIGHT_ON_DELAY_MASK) >>
168 		  PANEL_LIGHT_ON_DELAY_SHIFT;
169 
170 	val = I915_READ(PP_OFF_DELAYS(0));
171 	pps->t3 = (val & PANEL_POWER_DOWN_DELAY_MASK) >>
172 		  PANEL_POWER_DOWN_DELAY_SHIFT;
173 	pps->tx = (val & PANEL_LIGHT_OFF_DELAY_MASK) >>
174 		  PANEL_LIGHT_OFF_DELAY_SHIFT;
175 
176 	val = I915_READ(PP_DIVISOR(0));
177 	pps->divider = (val & PP_REFERENCE_DIVIDER_MASK) >>
178 		       PP_REFERENCE_DIVIDER_SHIFT;
179 	val = (val & PANEL_POWER_CYCLE_DELAY_MASK) >>
180 	      PANEL_POWER_CYCLE_DELAY_SHIFT;
181 	/*
182 	 * Remove the BSpec specified +1 (100ms) offset that accounts for a
183 	 * too short power-cycle delay due to the asynchronous programming of
184 	 * the register.
185 	 */
186 	if (val)
187 		val--;
188 	/* Convert from 100ms to 100us units */
189 	pps->t4 = val * 1000;
190 
191 	if (INTEL_INFO(dev_priv)->gen <= 4 &&
192 	    pps->t1_t2 == 0 && pps->t5 == 0 && pps->t3 == 0 && pps->tx == 0) {
193 		DRM_DEBUG_KMS("Panel power timings uninitialized, "
194 			      "setting defaults\n");
195 		/* Set T2 to 40ms and T5 to 200ms in 100 usec units */
196 		pps->t1_t2 = 40 * 10;
197 		pps->t5 = 200 * 10;
198 		/* Set T3 to 35ms and Tx to 200ms in 100 usec units */
199 		pps->t3 = 35 * 10;
200 		pps->tx = 200 * 10;
201 	}
202 
203 	DRM_DEBUG_DRIVER("LVDS PPS:t1+t2 %d t3 %d t4 %d t5 %d tx %d "
204 			 "divider %d port %d powerdown_on_reset %d\n",
205 			 pps->t1_t2, pps->t3, pps->t4, pps->t5, pps->tx,
206 			 pps->divider, pps->port, pps->powerdown_on_reset);
207 }
208 
209 static void intel_lvds_pps_init_hw(struct drm_i915_private *dev_priv,
210 				   struct intel_lvds_pps *pps)
211 {
212 	u32 val;
213 
214 	val = I915_READ(PP_CONTROL(0));
215 	WARN_ON((val & PANEL_UNLOCK_MASK) != PANEL_UNLOCK_REGS);
216 	if (pps->powerdown_on_reset)
217 		val |= PANEL_POWER_RESET;
218 	I915_WRITE(PP_CONTROL(0), val);
219 
220 	I915_WRITE(PP_ON_DELAYS(0), (pps->port << PANEL_PORT_SELECT_SHIFT) |
221 				    (pps->t1_t2 << PANEL_POWER_UP_DELAY_SHIFT) |
222 				    (pps->t5 << PANEL_LIGHT_ON_DELAY_SHIFT));
223 	I915_WRITE(PP_OFF_DELAYS(0), (pps->t3 << PANEL_POWER_DOWN_DELAY_SHIFT) |
224 				     (pps->tx << PANEL_LIGHT_OFF_DELAY_SHIFT));
225 
226 	val = pps->divider << PP_REFERENCE_DIVIDER_SHIFT;
227 	val |= (DIV_ROUND_UP(pps->t4, 1000) + 1) <<
228 	       PANEL_POWER_CYCLE_DELAY_SHIFT;
229 	I915_WRITE(PP_DIVISOR(0), val);
230 }
231 
232 static void intel_pre_enable_lvds(struct intel_encoder *encoder,
233 				  struct intel_crtc_state *pipe_config,
234 				  struct drm_connector_state *conn_state)
235 {
236 	struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
237 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
238 	struct intel_crtc *crtc = to_intel_crtc(pipe_config->base.crtc);
239 	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
240 	int pipe = crtc->pipe;
241 	u32 temp;
242 
243 	if (HAS_PCH_SPLIT(dev_priv)) {
244 		assert_fdi_rx_pll_disabled(dev_priv, pipe);
245 		assert_shared_dpll_disabled(dev_priv,
246 					    pipe_config->shared_dpll);
247 	} else {
248 		assert_pll_disabled(dev_priv, pipe);
249 	}
250 
251 	intel_lvds_pps_init_hw(dev_priv, &lvds_encoder->init_pps);
252 
253 	temp = lvds_encoder->init_lvds_val;
254 	temp |= LVDS_PORT_EN | LVDS_A0A2_CLKA_POWER_UP;
255 
256 	if (HAS_PCH_CPT(dev_priv)) {
257 		temp &= ~PORT_TRANS_SEL_MASK;
258 		temp |= PORT_TRANS_SEL_CPT(pipe);
259 	} else {
260 		if (pipe == 1) {
261 			temp |= LVDS_PIPEB_SELECT;
262 		} else {
263 			temp &= ~LVDS_PIPEB_SELECT;
264 		}
265 	}
266 
267 	/* set the corresponsding LVDS_BORDER bit */
268 	temp &= ~LVDS_BORDER_ENABLE;
269 	temp |= pipe_config->gmch_pfit.lvds_border_bits;
270 	/* Set the B0-B3 data pairs corresponding to whether we're going to
271 	 * set the DPLLs for dual-channel mode or not.
272 	 */
273 	if (lvds_encoder->is_dual_link)
274 		temp |= LVDS_B0B3_POWER_UP | LVDS_CLKB_POWER_UP;
275 	else
276 		temp &= ~(LVDS_B0B3_POWER_UP | LVDS_CLKB_POWER_UP);
277 
278 	/* It would be nice to set 24 vs 18-bit mode (LVDS_A3_POWER_UP)
279 	 * appropriately here, but we need to look more thoroughly into how
280 	 * panels behave in the two modes. For now, let's just maintain the
281 	 * value we got from the BIOS.
282 	 */
283 	temp &= ~LVDS_A3_POWER_MASK;
284 	temp |= lvds_encoder->a3_power;
285 
286 	/* Set the dithering flag on LVDS as needed, note that there is no
287 	 * special lvds dither control bit on pch-split platforms, dithering is
288 	 * only controlled through the PIPECONF reg. */
289 	if (IS_GEN4(dev_priv)) {
290 		/* Bspec wording suggests that LVDS port dithering only exists
291 		 * for 18bpp panels. */
292 		if (pipe_config->dither && pipe_config->pipe_bpp == 18)
293 			temp |= LVDS_ENABLE_DITHER;
294 		else
295 			temp &= ~LVDS_ENABLE_DITHER;
296 	}
297 	temp &= ~(LVDS_HSYNC_POLARITY | LVDS_VSYNC_POLARITY);
298 	if (adjusted_mode->flags & DRM_MODE_FLAG_NHSYNC)
299 		temp |= LVDS_HSYNC_POLARITY;
300 	if (adjusted_mode->flags & DRM_MODE_FLAG_NVSYNC)
301 		temp |= LVDS_VSYNC_POLARITY;
302 
303 	I915_WRITE(lvds_encoder->reg, temp);
304 }
305 
306 /**
307  * Sets the power state for the panel.
308  */
309 static void intel_enable_lvds(struct intel_encoder *encoder,
310 			      struct intel_crtc_state *pipe_config,
311 			      struct drm_connector_state *conn_state)
312 {
313 	struct drm_device *dev = encoder->base.dev;
314 	struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
315 	struct intel_connector *intel_connector =
316 		&lvds_encoder->attached_connector->base;
317 	struct drm_i915_private *dev_priv = to_i915(dev);
318 
319 	I915_WRITE(lvds_encoder->reg, I915_READ(lvds_encoder->reg) | LVDS_PORT_EN);
320 
321 	I915_WRITE(PP_CONTROL(0), I915_READ(PP_CONTROL(0)) | PANEL_POWER_ON);
322 	POSTING_READ(lvds_encoder->reg);
323 	if (intel_wait_for_register(dev_priv, PP_STATUS(0), PP_ON, PP_ON, 1000))
324 		DRM_ERROR("timed out waiting for panel to power on\n");
325 
326 	intel_panel_enable_backlight(intel_connector);
327 }
328 
329 static void intel_disable_lvds(struct intel_encoder *encoder,
330 			       struct intel_crtc_state *old_crtc_state,
331 			       struct drm_connector_state *old_conn_state)
332 {
333 	struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
334 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
335 
336 	I915_WRITE(PP_CONTROL(0), I915_READ(PP_CONTROL(0)) & ~PANEL_POWER_ON);
337 	if (intel_wait_for_register(dev_priv, PP_STATUS(0), PP_ON, 0, 1000))
338 		DRM_ERROR("timed out waiting for panel to power off\n");
339 
340 	I915_WRITE(lvds_encoder->reg, I915_READ(lvds_encoder->reg) & ~LVDS_PORT_EN);
341 	POSTING_READ(lvds_encoder->reg);
342 }
343 
344 static void gmch_disable_lvds(struct intel_encoder *encoder,
345 			      struct intel_crtc_state *old_crtc_state,
346 			      struct drm_connector_state *old_conn_state)
347 
348 {
349 	struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
350 	struct intel_connector *intel_connector =
351 		&lvds_encoder->attached_connector->base;
352 
353 	intel_panel_disable_backlight(intel_connector);
354 
355 	intel_disable_lvds(encoder, old_crtc_state, old_conn_state);
356 }
357 
358 static void pch_disable_lvds(struct intel_encoder *encoder,
359 			     struct intel_crtc_state *old_crtc_state,
360 			     struct drm_connector_state *old_conn_state)
361 {
362 	struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
363 	struct intel_connector *intel_connector =
364 		&lvds_encoder->attached_connector->base;
365 
366 	intel_panel_disable_backlight(intel_connector);
367 }
368 
369 static void pch_post_disable_lvds(struct intel_encoder *encoder,
370 				  struct intel_crtc_state *old_crtc_state,
371 				  struct drm_connector_state *old_conn_state)
372 {
373 	intel_disable_lvds(encoder, old_crtc_state, old_conn_state);
374 }
375 
376 static enum drm_mode_status
377 intel_lvds_mode_valid(struct drm_connector *connector,
378 		      struct drm_display_mode *mode)
379 {
380 	struct intel_connector *intel_connector = to_intel_connector(connector);
381 	struct drm_display_mode *fixed_mode = intel_connector->panel.fixed_mode;
382 	int max_pixclk = to_i915(connector->dev)->max_dotclk_freq;
383 
384 	if (mode->hdisplay > fixed_mode->hdisplay)
385 		return MODE_PANEL;
386 	if (mode->vdisplay > fixed_mode->vdisplay)
387 		return MODE_PANEL;
388 	if (fixed_mode->clock > max_pixclk)
389 		return MODE_CLOCK_HIGH;
390 
391 	return MODE_OK;
392 }
393 
394 static bool intel_lvds_compute_config(struct intel_encoder *intel_encoder,
395 				      struct intel_crtc_state *pipe_config,
396 				      struct drm_connector_state *conn_state)
397 {
398 	struct drm_i915_private *dev_priv = to_i915(intel_encoder->base.dev);
399 	struct intel_lvds_encoder *lvds_encoder =
400 		to_lvds_encoder(&intel_encoder->base);
401 	struct intel_connector *intel_connector =
402 		&lvds_encoder->attached_connector->base;
403 	struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
404 	struct intel_crtc *intel_crtc = to_intel_crtc(pipe_config->base.crtc);
405 	unsigned int lvds_bpp;
406 
407 	/* Should never happen!! */
408 	if (INTEL_GEN(dev_priv) < 4 && intel_crtc->pipe == 0) {
409 		DRM_ERROR("Can't support LVDS on pipe A\n");
410 		return false;
411 	}
412 
413 	if (lvds_encoder->a3_power == LVDS_A3_POWER_UP)
414 		lvds_bpp = 8*3;
415 	else
416 		lvds_bpp = 6*3;
417 
418 	if (lvds_bpp != pipe_config->pipe_bpp && !pipe_config->bw_constrained) {
419 		DRM_DEBUG_KMS("forcing display bpp (was %d) to LVDS (%d)\n",
420 			      pipe_config->pipe_bpp, lvds_bpp);
421 		pipe_config->pipe_bpp = lvds_bpp;
422 	}
423 
424 	/*
425 	 * We have timings from the BIOS for the panel, put them in
426 	 * to the adjusted mode.  The CRTC will be set up for this mode,
427 	 * with the panel scaling set up to source from the H/VDisplay
428 	 * of the original mode.
429 	 */
430 	intel_fixed_panel_mode(intel_connector->panel.fixed_mode,
431 			       adjusted_mode);
432 
433 	if (HAS_PCH_SPLIT(dev_priv)) {
434 		pipe_config->has_pch_encoder = true;
435 
436 		intel_pch_panel_fitting(intel_crtc, pipe_config,
437 					intel_connector->panel.fitting_mode);
438 	} else {
439 		intel_gmch_panel_fitting(intel_crtc, pipe_config,
440 					 intel_connector->panel.fitting_mode);
441 
442 	}
443 
444 	/*
445 	 * XXX: It would be nice to support lower refresh rates on the
446 	 * panels to reduce power consumption, and perhaps match the
447 	 * user's requested refresh rate.
448 	 */
449 
450 	return true;
451 }
452 
453 /**
454  * Detect the LVDS connection.
455  *
456  * Since LVDS doesn't have hotlug, we use the lid as a proxy.  Open means
457  * connected and closed means disconnected.  We also send hotplug events as
458  * needed, using lid status notification from the input layer.
459  */
460 static enum drm_connector_status
461 intel_lvds_detect(struct drm_connector *connector, bool force)
462 {
463 	struct drm_i915_private *dev_priv = to_i915(connector->dev);
464 	enum drm_connector_status status;
465 
466 	DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
467 		      connector->base.id, connector->name);
468 
469 	status = intel_panel_detect(dev_priv);
470 	if (status != connector_status_unknown)
471 		return status;
472 
473 	return connector_status_connected;
474 }
475 
476 /**
477  * Return the list of DDC modes if available, or the BIOS fixed mode otherwise.
478  */
479 static int intel_lvds_get_modes(struct drm_connector *connector)
480 {
481 	struct intel_lvds_connector *lvds_connector = to_lvds_connector(connector);
482 	struct drm_device *dev = connector->dev;
483 	struct drm_display_mode *mode;
484 
485 	/* use cached edid if we have one */
486 	if (!IS_ERR_OR_NULL(lvds_connector->base.edid))
487 		return drm_add_edid_modes(connector, lvds_connector->base.edid);
488 
489 	mode = drm_mode_duplicate(dev, lvds_connector->base.panel.fixed_mode);
490 	if (mode == NULL)
491 		return 0;
492 
493 	drm_mode_probed_add(connector, mode);
494 	return 1;
495 }
496 
497 #if 0 /* unused */
498 static int intel_no_modeset_on_lid_dmi_callback(const struct dmi_system_id *id)
499 {
500 	DRM_INFO("Skipping forced modeset for %s\n", id->ident);
501 	return 1;
502 }
503 
504 /* The GPU hangs up on these systems if modeset is performed on LID open */
505 static const struct dmi_system_id intel_no_modeset_on_lid[] = {
506 	{
507 		.callback = intel_no_modeset_on_lid_dmi_callback,
508 		.ident = "Toshiba Tecra A11",
509 		.matches = {
510 			DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
511 			DMI_MATCH(DMI_PRODUCT_NAME, "TECRA A11"),
512 		},
513 	},
514 
515 	{ }	/* terminating entry */
516 };
517 
518 /*
519  * Lid events. Note the use of 'modeset':
520  *  - we set it to MODESET_ON_LID_OPEN on lid close,
521  *    and set it to MODESET_DONE on open
522  *  - we use it as a "only once" bit (ie we ignore
523  *    duplicate events where it was already properly set)
524  *  - the suspend/resume paths will set it to
525  *    MODESET_SUSPENDED and ignore the lid open event,
526  *    because they restore the mode ("lid open").
527  */
528 static int intel_lid_notify(struct notifier_block *nb, unsigned long val,
529 			    void *unused)
530 {
531 	struct intel_lvds_connector *lvds_connector =
532 		container_of(nb, struct intel_lvds_connector, lid_notifier);
533 	struct drm_connector *connector = &lvds_connector->base.base;
534 	struct drm_device *dev = connector->dev;
535 	struct drm_i915_private *dev_priv = to_i915(dev);
536 
537 	if (dev->switch_power_state != DRM_SWITCH_POWER_ON)
538 		return NOTIFY_OK;
539 
540 	mutex_lock(&dev_priv->modeset_restore_lock);
541 	if (dev_priv->modeset_restore == MODESET_SUSPENDED)
542 		goto exit;
543 	/*
544 	 * check and update the status of LVDS connector after receiving
545 	 * the LID nofication event.
546 	 */
547 	connector->status = connector->funcs->detect(connector, false);
548 
549 	/* Don't force modeset on machines where it causes a GPU lockup */
550 	if (dmi_check_system(intel_no_modeset_on_lid))
551 		goto exit;
552 	if (!acpi_lid_open()) {
553 		/* do modeset on next lid open event */
554 		dev_priv->modeset_restore = MODESET_ON_LID_OPEN;
555 		goto exit;
556 	}
557 
558 	if (dev_priv->modeset_restore == MODESET_DONE)
559 		goto exit;
560 
561 	/*
562 	 * Some old platform's BIOS love to wreak havoc while the lid is closed.
563 	 * We try to detect this here and undo any damage. The split for PCH
564 	 * platforms is rather conservative and a bit arbitrary expect that on
565 	 * those platforms VGA disabling requires actual legacy VGA I/O access,
566 	 * and as part of the cleanup in the hw state restore we also redisable
567 	 * the vga plane.
568 	 */
569 	if (!HAS_PCH_SPLIT(dev_priv))
570 		intel_display_resume(dev);
571 
572 	dev_priv->modeset_restore = MODESET_DONE;
573 
574 exit:
575 	mutex_unlock(&dev_priv->modeset_restore_lock);
576 	return NOTIFY_OK;
577 }
578 #endif
579 
580 /**
581  * intel_lvds_destroy - unregister and free LVDS structures
582  * @connector: connector to free
583  *
584  * Unregister the DDC bus for this connector then free the driver private
585  * structure.
586  */
587 static void intel_lvds_destroy(struct drm_connector *connector)
588 {
589 	struct intel_lvds_connector *lvds_connector =
590 		to_lvds_connector(connector);
591 
592 #if 0
593 	if (lvds_connector->lid_notifier.notifier_call)
594 		acpi_lid_notifier_unregister(&lvds_connector->lid_notifier);
595 #endif
596 
597 	if (!IS_ERR_OR_NULL(lvds_connector->base.edid))
598 		kfree(lvds_connector->base.edid);
599 
600 	intel_panel_fini(&lvds_connector->base.panel);
601 
602 	drm_connector_cleanup(connector);
603 	kfree(connector);
604 }
605 
606 static int intel_lvds_set_property(struct drm_connector *connector,
607 				   struct drm_property *property,
608 				   uint64_t value)
609 {
610 	struct intel_connector *intel_connector = to_intel_connector(connector);
611 	struct drm_device *dev = connector->dev;
612 
613 	if (property == dev->mode_config.scaling_mode_property) {
614 		struct drm_crtc *crtc;
615 
616 		if (value == DRM_MODE_SCALE_NONE) {
617 			DRM_DEBUG_KMS("no scaling not supported\n");
618 			return -EINVAL;
619 		}
620 
621 		if (intel_connector->panel.fitting_mode == value) {
622 			/* the LVDS scaling property is not changed */
623 			return 0;
624 		}
625 		intel_connector->panel.fitting_mode = value;
626 
627 		crtc = intel_attached_encoder(connector)->base.crtc;
628 		if (crtc && crtc->state->enable) {
629 			/*
630 			 * If the CRTC is enabled, the display will be changed
631 			 * according to the new panel fitting mode.
632 			 */
633 			intel_crtc_restore_mode(crtc);
634 		}
635 	}
636 
637 	return 0;
638 }
639 
640 static const struct drm_connector_helper_funcs intel_lvds_connector_helper_funcs = {
641 	.get_modes = intel_lvds_get_modes,
642 	.mode_valid = intel_lvds_mode_valid,
643 };
644 
645 static const struct drm_connector_funcs intel_lvds_connector_funcs = {
646 	.dpms = drm_atomic_helper_connector_dpms,
647 	.detect = intel_lvds_detect,
648 	.fill_modes = drm_helper_probe_single_connector_modes,
649 	.set_property = intel_lvds_set_property,
650 	.atomic_get_property = intel_connector_atomic_get_property,
651 	.late_register = intel_connector_register,
652 	.early_unregister = intel_connector_unregister,
653 	.destroy = intel_lvds_destroy,
654 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
655 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
656 };
657 
658 static const struct drm_encoder_funcs intel_lvds_enc_funcs = {
659 	.destroy = intel_encoder_destroy,
660 };
661 
662 static int intel_no_lvds_dmi_callback(const struct dmi_system_id *id)
663 {
664 	DRM_INFO("Skipping LVDS initialization for %s\n", id->ident);
665 	return 1;
666 }
667 
668 /* These systems claim to have LVDS, but really don't */
669 static const struct dmi_system_id intel_no_lvds[] = {
670 	{
671 		.callback = intel_no_lvds_dmi_callback,
672 		.ident = "Apple Mac Mini (Core series)",
673 		.matches = {
674 			DMI_MATCH(DMI_SYS_VENDOR, "Apple"),
675 			DMI_MATCH(DMI_PRODUCT_NAME, "Macmini1,1"),
676 		},
677 	},
678 	{
679 		.callback = intel_no_lvds_dmi_callback,
680 		.ident = "Apple Mac Mini (Core 2 series)",
681 		.matches = {
682 			DMI_MATCH(DMI_SYS_VENDOR, "Apple"),
683 			DMI_MATCH(DMI_PRODUCT_NAME, "Macmini2,1"),
684 		},
685 	},
686 	{
687 		.callback = intel_no_lvds_dmi_callback,
688 		.ident = "MSI IM-945GSE-A",
689 		.matches = {
690 			DMI_MATCH(DMI_SYS_VENDOR, "MSI"),
691 			DMI_MATCH(DMI_PRODUCT_NAME, "A9830IMS"),
692 		},
693 	},
694 	{
695 		.callback = intel_no_lvds_dmi_callback,
696 		.ident = "Dell Studio Hybrid",
697 		.matches = {
698 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
699 			DMI_MATCH(DMI_PRODUCT_NAME, "Studio Hybrid 140g"),
700 		},
701 	},
702 	{
703 		.callback = intel_no_lvds_dmi_callback,
704 		.ident = "Dell OptiPlex FX170",
705 		.matches = {
706 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
707 			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex FX170"),
708 		},
709 	},
710 	{
711 		.callback = intel_no_lvds_dmi_callback,
712 		.ident = "AOpen Mini PC",
713 		.matches = {
714 			DMI_MATCH(DMI_SYS_VENDOR, "AOpen"),
715 			DMI_MATCH(DMI_PRODUCT_NAME, "i965GMx-IF"),
716 		},
717 	},
718 	{
719 		.callback = intel_no_lvds_dmi_callback,
720 		.ident = "AOpen Mini PC MP915",
721 		.matches = {
722 			DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
723 			DMI_MATCH(DMI_BOARD_NAME, "i915GMx-F"),
724 		},
725 	},
726 	{
727 		.callback = intel_no_lvds_dmi_callback,
728 		.ident = "AOpen i915GMm-HFS",
729 		.matches = {
730 			DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
731 			DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
732 		},
733 	},
734 	{
735 		.callback = intel_no_lvds_dmi_callback,
736                 .ident = "AOpen i45GMx-I",
737                 .matches = {
738                         DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
739                         DMI_MATCH(DMI_BOARD_NAME, "i45GMx-I"),
740                 },
741         },
742 	{
743 		.callback = intel_no_lvds_dmi_callback,
744 		.ident = "Aopen i945GTt-VFA",
745 		.matches = {
746 			DMI_MATCH(DMI_PRODUCT_VERSION, "AO00001JW"),
747 		},
748 	},
749 	{
750 		.callback = intel_no_lvds_dmi_callback,
751 		.ident = "Clientron U800",
752 		.matches = {
753 			DMI_MATCH(DMI_SYS_VENDOR, "Clientron"),
754 			DMI_MATCH(DMI_PRODUCT_NAME, "U800"),
755 		},
756 	},
757 	{
758                 .callback = intel_no_lvds_dmi_callback,
759                 .ident = "Clientron E830",
760                 .matches = {
761                         DMI_MATCH(DMI_SYS_VENDOR, "Clientron"),
762                         DMI_MATCH(DMI_PRODUCT_NAME, "E830"),
763                 },
764         },
765         {
766 		.callback = intel_no_lvds_dmi_callback,
767 		.ident = "Asus EeeBox PC EB1007",
768 		.matches = {
769 			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer INC."),
770 			DMI_MATCH(DMI_PRODUCT_NAME, "EB1007"),
771 		},
772 	},
773 	{
774 		.callback = intel_no_lvds_dmi_callback,
775 		.ident = "Asus AT5NM10T-I",
776 		.matches = {
777 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
778 			DMI_MATCH(DMI_BOARD_NAME, "AT5NM10T-I"),
779 		},
780 	},
781 	{
782 		.callback = intel_no_lvds_dmi_callback,
783 		.ident = "Hewlett-Packard HP t5740",
784 		.matches = {
785 			DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
786 			DMI_MATCH(DMI_PRODUCT_NAME, " t5740"),
787 		},
788 	},
789 	{
790 		.callback = intel_no_lvds_dmi_callback,
791 		.ident = "Hewlett-Packard t5745",
792 		.matches = {
793 			DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
794 			DMI_MATCH(DMI_PRODUCT_NAME, "hp t5745"),
795 		},
796 	},
797 	{
798 		.callback = intel_no_lvds_dmi_callback,
799 		.ident = "Hewlett-Packard st5747",
800 		.matches = {
801 			DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
802 			DMI_MATCH(DMI_PRODUCT_NAME, "hp st5747"),
803 		},
804 	},
805 	{
806 		.callback = intel_no_lvds_dmi_callback,
807 		.ident = "MSI Wind Box DC500",
808 		.matches = {
809 			DMI_MATCH(DMI_BOARD_VENDOR, "MICRO-STAR INTERNATIONAL CO., LTD"),
810 			DMI_MATCH(DMI_BOARD_NAME, "MS-7469"),
811 		},
812 	},
813 	{
814 		.callback = intel_no_lvds_dmi_callback,
815 		.ident = "Gigabyte GA-D525TUD",
816 		.matches = {
817 			DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
818 			DMI_MATCH(DMI_BOARD_NAME, "D525TUD"),
819 		},
820 	},
821 	{
822 		.callback = intel_no_lvds_dmi_callback,
823 		.ident = "Supermicro X7SPA-H",
824 		.matches = {
825 			DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
826 			DMI_MATCH(DMI_PRODUCT_NAME, "X7SPA-H"),
827 		},
828 	},
829 	{
830 		.callback = intel_no_lvds_dmi_callback,
831 		.ident = "Fujitsu Esprimo Q900",
832 		.matches = {
833 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
834 			DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Q900"),
835 		},
836 	},
837 	{
838 		.callback = intel_no_lvds_dmi_callback,
839 		.ident = "Intel D410PT",
840 		.matches = {
841 			DMI_MATCH(DMI_BOARD_VENDOR, "Intel"),
842 			DMI_MATCH(DMI_BOARD_NAME, "D410PT"),
843 		},
844 	},
845 	{
846 		.callback = intel_no_lvds_dmi_callback,
847 		.ident = "Intel D425KT",
848 		.matches = {
849 			DMI_MATCH(DMI_BOARD_VENDOR, "Intel"),
850 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "D425KT"),
851 		},
852 	},
853 	{
854 		.callback = intel_no_lvds_dmi_callback,
855 		.ident = "Intel D510MO",
856 		.matches = {
857 			DMI_MATCH(DMI_BOARD_VENDOR, "Intel"),
858 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "D510MO"),
859 		},
860 	},
861 	{
862 		.callback = intel_no_lvds_dmi_callback,
863 		.ident = "Intel D525MW",
864 		.matches = {
865 			DMI_MATCH(DMI_BOARD_VENDOR, "Intel"),
866 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "D525MW"),
867 		},
868 	},
869 
870 	{ }	/* terminating entry */
871 };
872 
873 static int intel_dual_link_lvds_callback(const struct dmi_system_id *id)
874 {
875 	DRM_INFO("Forcing lvds to dual link mode on %s\n", id->ident);
876 	return 1;
877 }
878 
879 static const struct dmi_system_id intel_dual_link_lvds[] = {
880 	{
881 		.callback = intel_dual_link_lvds_callback,
882 		.ident = "Apple MacBook Pro 15\" (2010)",
883 		.matches = {
884 			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
885 			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro6,2"),
886 		},
887 	},
888 	{
889 		.callback = intel_dual_link_lvds_callback,
890 		.ident = "Apple MacBook Pro 15\" (2011)",
891 		.matches = {
892 			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
893 			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro8,2"),
894 		},
895 	},
896 	{
897 		.callback = intel_dual_link_lvds_callback,
898 		.ident = "Apple MacBook Pro 15\" (2012)",
899 		.matches = {
900 			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
901 			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro9,1"),
902 		},
903 	},
904 	{ }	/* terminating entry */
905 };
906 
907 struct intel_encoder *intel_get_lvds_encoder(struct drm_device *dev)
908 {
909 	struct intel_encoder *intel_encoder;
910 
911 	for_each_intel_encoder(dev, intel_encoder)
912 		if (intel_encoder->type == INTEL_OUTPUT_LVDS)
913 			return intel_encoder;
914 
915 	return NULL;
916 }
917 
918 bool intel_is_dual_link_lvds(struct drm_device *dev)
919 {
920 	struct intel_encoder *encoder = intel_get_lvds_encoder(dev);
921 
922 	return encoder && to_lvds_encoder(&encoder->base)->is_dual_link;
923 }
924 
925 static bool compute_is_dual_link_lvds(struct intel_lvds_encoder *lvds_encoder)
926 {
927 	struct drm_device *dev = lvds_encoder->base.base.dev;
928 	unsigned int val;
929 	struct drm_i915_private *dev_priv = to_i915(dev);
930 
931 	/* use the module option value if specified */
932 	if (i915.lvds_channel_mode > 0)
933 		return i915.lvds_channel_mode == 2;
934 
935 	/* single channel LVDS is limited to 112 MHz */
936 	if (lvds_encoder->attached_connector->base.panel.fixed_mode->clock
937 	    > 112999)
938 		return true;
939 
940 	if (dmi_check_system(intel_dual_link_lvds))
941 		return true;
942 
943 	/* BIOS should set the proper LVDS register value at boot, but
944 	 * in reality, it doesn't set the value when the lid is closed;
945 	 * we need to check "the value to be set" in VBT when LVDS
946 	 * register is uninitialized.
947 	 */
948 	val = I915_READ(lvds_encoder->reg);
949 	if (!(val & ~(LVDS_PIPE_MASK | LVDS_DETECTED)))
950 		val = dev_priv->vbt.bios_lvds_val;
951 
952 	return (val & LVDS_CLKB_POWER_MASK) == LVDS_CLKB_POWER_UP;
953 }
954 
955 static bool intel_lvds_supported(struct drm_i915_private *dev_priv)
956 {
957 	/* With the introduction of the PCH we gained a dedicated
958 	 * LVDS presence pin, use it. */
959 	if (HAS_PCH_IBX(dev_priv) || HAS_PCH_CPT(dev_priv))
960 		return true;
961 
962 	/* Otherwise LVDS was only attached to mobile products,
963 	 * except for the inglorious 830gm */
964 	if (INTEL_GEN(dev_priv) <= 4 &&
965 	    IS_MOBILE(dev_priv) && !IS_I830(dev_priv))
966 		return true;
967 
968 	return false;
969 }
970 
971 /**
972  * intel_lvds_init - setup LVDS connectors on this device
973  * @dev: drm device
974  *
975  * Create the connector, register the LVDS DDC bus, and try to figure out what
976  * modes we can display on the LVDS panel (if present).
977  */
978 void intel_lvds_init(struct drm_i915_private *dev_priv)
979 {
980 	struct drm_device *dev = &dev_priv->drm;
981 	struct intel_lvds_encoder *lvds_encoder;
982 	struct intel_encoder *intel_encoder;
983 	struct intel_lvds_connector *lvds_connector;
984 	struct intel_connector *intel_connector;
985 	struct drm_connector *connector;
986 	struct drm_encoder *encoder;
987 	struct drm_display_mode *scan; /* *modes, *bios_mode; */
988 	struct drm_display_mode *fixed_mode = NULL;
989 	struct drm_display_mode *downclock_mode = NULL;
990 	struct edid *edid;
991 	struct intel_crtc *crtc;
992 	i915_reg_t lvds_reg;
993 	u32 lvds;
994 	int pipe;
995 	u8 pin;
996 
997 	if (!intel_lvds_supported(dev_priv))
998 		return;
999 
1000 	/* Skip init on machines we know falsely report LVDS */
1001 	if (dmi_check_system(intel_no_lvds))
1002 		return;
1003 
1004 	if (HAS_PCH_SPLIT(dev_priv))
1005 		lvds_reg = PCH_LVDS;
1006 	else
1007 		lvds_reg = LVDS;
1008 
1009 	lvds = I915_READ(lvds_reg);
1010 
1011 	if (HAS_PCH_SPLIT(dev_priv)) {
1012 		if ((lvds & LVDS_DETECTED) == 0)
1013 			return;
1014 		if (dev_priv->vbt.edp.support) {
1015 			DRM_DEBUG_KMS("disable LVDS for eDP support\n");
1016 			return;
1017 		}
1018 	}
1019 
1020 	pin = GMBUS_PIN_PANEL;
1021 	if (!intel_bios_is_lvds_present(dev_priv, &pin)) {
1022 		if ((lvds & LVDS_PORT_EN) == 0) {
1023 			DRM_DEBUG_KMS("LVDS is not present in VBT\n");
1024 			return;
1025 		}
1026 		DRM_DEBUG_KMS("LVDS is not present in VBT, but enabled anyway\n");
1027 	}
1028 
1029 	lvds_encoder = kzalloc(sizeof(*lvds_encoder), GFP_KERNEL);
1030 	if (!lvds_encoder)
1031 		return;
1032 
1033 	lvds_connector = kzalloc(sizeof(*lvds_connector), GFP_KERNEL);
1034 	if (!lvds_connector) {
1035 		kfree(lvds_encoder);
1036 		return;
1037 	}
1038 
1039 	if (intel_connector_init(&lvds_connector->base) < 0) {
1040 		kfree(lvds_connector);
1041 		kfree(lvds_encoder);
1042 		return;
1043 	}
1044 
1045 	lvds_encoder->attached_connector = lvds_connector;
1046 
1047 	intel_encoder = &lvds_encoder->base;
1048 	encoder = &intel_encoder->base;
1049 	intel_connector = &lvds_connector->base;
1050 	connector = &intel_connector->base;
1051 	drm_connector_init(dev, &intel_connector->base, &intel_lvds_connector_funcs,
1052 			   DRM_MODE_CONNECTOR_LVDS);
1053 
1054 	drm_encoder_init(dev, &intel_encoder->base, &intel_lvds_enc_funcs,
1055 			 DRM_MODE_ENCODER_LVDS, "LVDS");
1056 
1057 	intel_encoder->enable = intel_enable_lvds;
1058 	intel_encoder->pre_enable = intel_pre_enable_lvds;
1059 	intel_encoder->compute_config = intel_lvds_compute_config;
1060 	if (HAS_PCH_SPLIT(dev_priv)) {
1061 		intel_encoder->disable = pch_disable_lvds;
1062 		intel_encoder->post_disable = pch_post_disable_lvds;
1063 	} else {
1064 		intel_encoder->disable = gmch_disable_lvds;
1065 	}
1066 	intel_encoder->get_hw_state = intel_lvds_get_hw_state;
1067 	intel_encoder->get_config = intel_lvds_get_config;
1068 	intel_connector->get_hw_state = intel_connector_get_hw_state;
1069 
1070 	intel_connector_attach_encoder(intel_connector, intel_encoder);
1071 
1072 	intel_encoder->type = INTEL_OUTPUT_LVDS;
1073 	intel_encoder->power_domain = POWER_DOMAIN_PORT_OTHER;
1074 	intel_encoder->port = PORT_NONE;
1075 	intel_encoder->cloneable = 0;
1076 	if (HAS_PCH_SPLIT(dev_priv))
1077 		intel_encoder->crtc_mask = (1 << 0) | (1 << 1) | (1 << 2);
1078 	else if (IS_GEN4(dev_priv))
1079 		intel_encoder->crtc_mask = (1 << 0) | (1 << 1);
1080 	else
1081 		intel_encoder->crtc_mask = (1 << 1);
1082 
1083 	drm_connector_helper_add(connector, &intel_lvds_connector_helper_funcs);
1084 	connector->display_info.subpixel_order = SubPixelHorizontalRGB;
1085 	connector->interlace_allowed = false;
1086 	connector->doublescan_allowed = false;
1087 
1088 	lvds_encoder->reg = lvds_reg;
1089 
1090 	/* create the scaling mode property */
1091 	drm_mode_create_scaling_mode_property(dev);
1092 	drm_object_attach_property(&connector->base,
1093 				      dev->mode_config.scaling_mode_property,
1094 				      DRM_MODE_SCALE_ASPECT);
1095 	intel_connector->panel.fitting_mode = DRM_MODE_SCALE_ASPECT;
1096 
1097 	intel_lvds_pps_get_hw_state(dev_priv, &lvds_encoder->init_pps);
1098 	lvds_encoder->init_lvds_val = lvds;
1099 
1100 	/*
1101 	 * LVDS discovery:
1102 	 * 1) check for EDID on DDC
1103 	 * 2) check for VBT data
1104 	 * 3) check to see if LVDS is already on
1105 	 *    if none of the above, no panel
1106 	 * 4) make sure lid is open
1107 	 *    if closed, act like it's not there for now
1108 	 */
1109 
1110 	/*
1111 	 * Attempt to get the fixed panel mode from DDC.  Assume that the
1112 	 * preferred mode is the right one.
1113 	 */
1114 	mutex_lock(&dev->mode_config.mutex);
1115 	if (vga_switcheroo_handler_flags() & VGA_SWITCHEROO_CAN_SWITCH_DDC)
1116 		edid = drm_get_edid_switcheroo(connector,
1117 				    intel_gmbus_get_adapter(dev_priv, pin));
1118 	else
1119 		edid = drm_get_edid(connector,
1120 				    intel_gmbus_get_adapter(dev_priv, pin));
1121 	if (edid) {
1122 		if (drm_add_edid_modes(connector, edid)) {
1123 			drm_mode_connector_update_edid_property(connector,
1124 								edid);
1125 		} else {
1126 			kfree(edid);
1127 			edid = ERR_PTR(-EINVAL);
1128 		}
1129 	} else {
1130 		edid = ERR_PTR(-ENOENT);
1131 	}
1132 	lvds_connector->base.edid = edid;
1133 
1134 	list_for_each_entry(scan, &connector->probed_modes, head) {
1135 		if (scan->type & DRM_MODE_TYPE_PREFERRED) {
1136 			DRM_DEBUG_KMS("using preferred mode from EDID: ");
1137 			drm_mode_debug_printmodeline(scan);
1138 
1139 			fixed_mode = drm_mode_duplicate(dev, scan);
1140 			if (fixed_mode)
1141 				goto out;
1142 		}
1143 	}
1144 
1145 	/* Failed to get EDID, what about VBT? */
1146 	if (dev_priv->vbt.lfp_lvds_vbt_mode) {
1147 		DRM_DEBUG_KMS("using mode from VBT: ");
1148 		drm_mode_debug_printmodeline(dev_priv->vbt.lfp_lvds_vbt_mode);
1149 
1150 		fixed_mode = drm_mode_duplicate(dev, dev_priv->vbt.lfp_lvds_vbt_mode);
1151 		if (fixed_mode) {
1152 			fixed_mode->type |= DRM_MODE_TYPE_PREFERRED;
1153 			connector->display_info.width_mm = fixed_mode->width_mm;
1154 			connector->display_info.height_mm = fixed_mode->height_mm;
1155 			goto out;
1156 		}
1157 	}
1158 
1159 	/*
1160 	 * If we didn't get EDID, try checking if the panel is already turned
1161 	 * on.  If so, assume that whatever is currently programmed is the
1162 	 * correct mode.
1163 	 */
1164 
1165 	/* Ironlake: FIXME if still fail, not try pipe mode now */
1166 	if (HAS_PCH_SPLIT(dev_priv))
1167 		goto failed;
1168 
1169 	pipe = (lvds & LVDS_PIPEB_SELECT) ? 1 : 0;
1170 	crtc = intel_get_crtc_for_pipe(dev_priv, pipe);
1171 
1172 	if (crtc && (lvds & LVDS_PORT_EN)) {
1173 		fixed_mode = intel_crtc_mode_get(dev, &crtc->base);
1174 		if (fixed_mode) {
1175 			DRM_DEBUG_KMS("using current (BIOS) mode: ");
1176 			drm_mode_debug_printmodeline(fixed_mode);
1177 			fixed_mode->type |= DRM_MODE_TYPE_PREFERRED;
1178 			goto out;
1179 		}
1180 	}
1181 
1182 	/* If we still don't have a mode after all that, give up. */
1183 	if (!fixed_mode)
1184 		goto failed;
1185 
1186 out:
1187 	mutex_unlock(&dev->mode_config.mutex);
1188 
1189 	intel_panel_init(&intel_connector->panel, fixed_mode, downclock_mode);
1190 	intel_panel_setup_backlight(connector, INVALID_PIPE);
1191 
1192 	lvds_encoder->is_dual_link = compute_is_dual_link_lvds(lvds_encoder);
1193 	DRM_DEBUG_KMS("detected %s-link lvds configuration\n",
1194 		      lvds_encoder->is_dual_link ? "dual" : "single");
1195 
1196 	lvds_encoder->a3_power = lvds & LVDS_A3_POWER_MASK;
1197 
1198 #if 0
1199 	lvds_connector->lid_notifier.notifier_call = intel_lid_notify;
1200 	if (acpi_lid_notifier_register(&lvds_connector->lid_notifier)) {
1201 		DRM_DEBUG_KMS("lid notifier registration failed\n");
1202 		lvds_connector->lid_notifier.notifier_call = NULL;
1203 	}
1204 #endif
1205 
1206 	return;
1207 
1208 failed:
1209 	mutex_unlock(&dev->mode_config.mutex);
1210 
1211 	DRM_DEBUG_KMS("No LVDS modes found, disabling.\n");
1212 	drm_connector_cleanup(connector);
1213 	drm_encoder_cleanup(encoder);
1214 	kfree(lvds_encoder);
1215 	kfree(lvds_connector);
1216 	return;
1217 }
1218