1 /*
2  * Copyright © 2006-2011 Intel Corporation
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, write to the Free Software Foundation, Inc.,
15  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
16  *
17  * Authors:
18  *	Eric Anholt <eric@anholt.net>
19  *	Dave Airlie <airlied@linux.ie>
20  *	Jesse Barnes <jesse.barnes@intel.com>
21  */
22 
23 #include <linux/i2c.h>
24 #include <linux/dmi.h>
25 #include <drm/drmP.h>
26 
27 #include "intel_bios.h"
28 #include "psb_drv.h"
29 #include "psb_intel_drv.h"
30 #include "psb_intel_reg.h"
31 #include "power.h"
32 #include <linux/pm_runtime.h>
33 #include "cdv_device.h"
34 
35 /**
36  * LVDS I2C backlight control macros
37  */
38 #define BRIGHTNESS_MAX_LEVEL 100
39 #define BRIGHTNESS_MASK 0xFF
40 #define BLC_I2C_TYPE	0x01
41 #define BLC_PWM_TYPT	0x02
42 
43 #define BLC_POLARITY_NORMAL 0
44 #define BLC_POLARITY_INVERSE 1
45 
46 #define PSB_BLC_MAX_PWM_REG_FREQ       (0xFFFE)
47 #define PSB_BLC_MIN_PWM_REG_FREQ	(0x2)
48 #define PSB_BLC_PWM_PRECISION_FACTOR	(10)
49 #define PSB_BACKLIGHT_PWM_CTL_SHIFT	(16)
50 #define PSB_BACKLIGHT_PWM_POLARITY_BIT_CLEAR (0xFFFE)
51 
52 struct cdv_intel_lvds_priv {
53 	/**
54 	 * Saved LVDO output states
55 	 */
56 	uint32_t savePP_ON;
57 	uint32_t savePP_OFF;
58 	uint32_t saveLVDS;
59 	uint32_t savePP_CONTROL;
60 	uint32_t savePP_CYCLE;
61 	uint32_t savePFIT_CONTROL;
62 	uint32_t savePFIT_PGM_RATIOS;
63 	uint32_t saveBLC_PWM_CTL;
64 };
65 
66 /*
67  * Returns the maximum level of the backlight duty cycle field.
68  */
69 static u32 cdv_intel_lvds_get_max_backlight(struct drm_device *dev)
70 {
71 	struct drm_psb_private *dev_priv = dev->dev_private;
72 	u32 retval;
73 
74 	if (gma_power_begin(dev, false)) {
75 		retval = ((REG_READ(BLC_PWM_CTL) &
76 			  BACKLIGHT_MODULATION_FREQ_MASK) >>
77 			  BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
78 
79 		gma_power_end(dev);
80 	} else
81 		retval = ((dev_priv->regs.saveBLC_PWM_CTL &
82 			  BACKLIGHT_MODULATION_FREQ_MASK) >>
83 			  BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
84 
85 	return retval;
86 }
87 
88 #if 0
89 /*
90  * Set LVDS backlight level by I2C command
91  */
92 static int cdv_lvds_i2c_set_brightness(struct drm_device *dev,
93 					unsigned int level)
94 {
95 	struct drm_psb_private *dev_priv = dev->dev_private;
96 	struct psb_intel_i2c_chan *lvds_i2c_bus = dev_priv->lvds_i2c_bus;
97 	u8 out_buf[2];
98 	unsigned int blc_i2c_brightness;
99 
100 	struct i2c_msg msgs[] = {
101 		{
102 			.addr = lvds_i2c_bus->slave_addr,
103 			.flags = 0,
104 			.len = 2,
105 			.buf = out_buf,
106 		}
107 	};
108 
109 	blc_i2c_brightness = BRIGHTNESS_MASK & ((unsigned int)level *
110 			     BRIGHTNESS_MASK /
111 			     BRIGHTNESS_MAX_LEVEL);
112 
113 	if (dev_priv->lvds_bl->pol == BLC_POLARITY_INVERSE)
114 		blc_i2c_brightness = BRIGHTNESS_MASK - blc_i2c_brightness;
115 
116 	out_buf[0] = dev_priv->lvds_bl->brightnesscmd;
117 	out_buf[1] = (u8)blc_i2c_brightness;
118 
119 	if (i2c_transfer(&lvds_i2c_bus->adapter, msgs, 1) == 1)
120 		return 0;
121 
122 	DRM_ERROR("I2C transfer error\n");
123 	return -1;
124 }
125 
126 
127 static int cdv_lvds_pwm_set_brightness(struct drm_device *dev, int level)
128 {
129 	struct drm_psb_private *dev_priv = dev->dev_private;
130 
131 	u32 max_pwm_blc;
132 	u32 blc_pwm_duty_cycle;
133 
134 	max_pwm_blc = cdv_intel_lvds_get_max_backlight(dev);
135 
136 	/*BLC_PWM_CTL Should be initiated while backlight device init*/
137 	BUG_ON((max_pwm_blc & PSB_BLC_MAX_PWM_REG_FREQ) == 0);
138 
139 	blc_pwm_duty_cycle = level * max_pwm_blc / BRIGHTNESS_MAX_LEVEL;
140 
141 	if (dev_priv->lvds_bl->pol == BLC_POLARITY_INVERSE)
142 		blc_pwm_duty_cycle = max_pwm_blc - blc_pwm_duty_cycle;
143 
144 	blc_pwm_duty_cycle &= PSB_BACKLIGHT_PWM_POLARITY_BIT_CLEAR;
145 	REG_WRITE(BLC_PWM_CTL,
146 		  (max_pwm_blc << PSB_BACKLIGHT_PWM_CTL_SHIFT) |
147 		  (blc_pwm_duty_cycle));
148 
149 	return 0;
150 }
151 
152 /*
153  * Set LVDS backlight level either by I2C or PWM
154  */
155 void cdv_intel_lvds_set_brightness(struct drm_device *dev, int level)
156 {
157 	struct drm_psb_private *dev_priv = dev->dev_private;
158 
159 	if (!dev_priv->lvds_bl) {
160 		DRM_ERROR("NO LVDS Backlight Info\n");
161 		return;
162 	}
163 
164 	if (dev_priv->lvds_bl->type == BLC_I2C_TYPE)
165 		cdv_lvds_i2c_set_brightness(dev, level);
166 	else
167 		cdv_lvds_pwm_set_brightness(dev, level);
168 }
169 #endif
170 
171 /**
172  * Sets the backlight level.
173  *
174  * level backlight level, from 0 to cdv_intel_lvds_get_max_backlight().
175  */
176 static void cdv_intel_lvds_set_backlight(struct drm_device *dev, int level)
177 {
178 	struct drm_psb_private *dev_priv = dev->dev_private;
179 	u32 blc_pwm_ctl;
180 
181 	if (gma_power_begin(dev, false)) {
182 		blc_pwm_ctl =
183 			REG_READ(BLC_PWM_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
184 		REG_WRITE(BLC_PWM_CTL,
185 				(blc_pwm_ctl |
186 				(level << BACKLIGHT_DUTY_CYCLE_SHIFT)));
187 		gma_power_end(dev);
188 	} else {
189 		blc_pwm_ctl = dev_priv->regs.saveBLC_PWM_CTL &
190 				~BACKLIGHT_DUTY_CYCLE_MASK;
191 		dev_priv->regs.saveBLC_PWM_CTL = (blc_pwm_ctl |
192 					(level << BACKLIGHT_DUTY_CYCLE_SHIFT));
193 	}
194 }
195 
196 /**
197  * Sets the power state for the panel.
198  */
199 static void cdv_intel_lvds_set_power(struct drm_device *dev,
200 				     struct drm_encoder *encoder, bool on)
201 {
202 	struct drm_psb_private *dev_priv = dev->dev_private;
203 	u32 pp_status;
204 
205 	if (!gma_power_begin(dev, true))
206 		return;
207 
208 	if (on) {
209 		REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) |
210 			  POWER_TARGET_ON);
211 		do {
212 			pp_status = REG_READ(PP_STATUS);
213 		} while ((pp_status & PP_ON) == 0);
214 
215 		cdv_intel_lvds_set_backlight(dev,
216 				dev_priv->mode_dev.backlight_duty_cycle);
217 	} else {
218 		cdv_intel_lvds_set_backlight(dev, 0);
219 
220 		REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) &
221 			  ~POWER_TARGET_ON);
222 		do {
223 			pp_status = REG_READ(PP_STATUS);
224 		} while (pp_status & PP_ON);
225 	}
226 	gma_power_end(dev);
227 }
228 
229 static void cdv_intel_lvds_encoder_dpms(struct drm_encoder *encoder, int mode)
230 {
231 	struct drm_device *dev = encoder->dev;
232 	if (mode == DRM_MODE_DPMS_ON)
233 		cdv_intel_lvds_set_power(dev, encoder, true);
234 	else
235 		cdv_intel_lvds_set_power(dev, encoder, false);
236 	/* XXX: We never power down the LVDS pairs. */
237 }
238 
239 static void cdv_intel_lvds_save(struct drm_connector *connector)
240 {
241 }
242 
243 static void cdv_intel_lvds_restore(struct drm_connector *connector)
244 {
245 }
246 
247 static int cdv_intel_lvds_mode_valid(struct drm_connector *connector,
248 			      struct drm_display_mode *mode)
249 {
250 	struct drm_device *dev = connector->dev;
251 	struct drm_psb_private *dev_priv = dev->dev_private;
252 	struct drm_display_mode *fixed_mode =
253 					dev_priv->mode_dev.panel_fixed_mode;
254 
255 	/* just in case */
256 	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
257 		return MODE_NO_DBLESCAN;
258 
259 	/* just in case */
260 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
261 		return MODE_NO_INTERLACE;
262 
263 	if (fixed_mode) {
264 		if (mode->hdisplay > fixed_mode->hdisplay)
265 			return MODE_PANEL;
266 		if (mode->vdisplay > fixed_mode->vdisplay)
267 			return MODE_PANEL;
268 	}
269 	return MODE_OK;
270 }
271 
272 static bool cdv_intel_lvds_mode_fixup(struct drm_encoder *encoder,
273 				  const struct drm_display_mode *mode,
274 				  struct drm_display_mode *adjusted_mode)
275 {
276 	struct drm_device *dev = encoder->dev;
277 	struct drm_psb_private *dev_priv = dev->dev_private;
278 	struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
279 	struct drm_encoder *tmp_encoder;
280 	struct drm_display_mode *panel_fixed_mode = mode_dev->panel_fixed_mode;
281 
282 	/* Should never happen!! */
283 	list_for_each_entry(tmp_encoder, &dev->mode_config.encoder_list,
284 			    head) {
285 		if (tmp_encoder != encoder
286 		    && tmp_encoder->crtc == encoder->crtc) {
287 			printk(KERN_ERR "Can't enable LVDS and another "
288 			       "encoder on the same pipe\n");
289 			return false;
290 		}
291 	}
292 
293 	/*
294 	 * If we have timings from the BIOS for the panel, put them in
295 	 * to the adjusted mode.  The CRTC will be set up for this mode,
296 	 * with the panel scaling set up to source from the H/VDisplay
297 	 * of the original mode.
298 	 */
299 	if (panel_fixed_mode != NULL) {
300 		adjusted_mode->hdisplay = panel_fixed_mode->hdisplay;
301 		adjusted_mode->hsync_start = panel_fixed_mode->hsync_start;
302 		adjusted_mode->hsync_end = panel_fixed_mode->hsync_end;
303 		adjusted_mode->htotal = panel_fixed_mode->htotal;
304 		adjusted_mode->vdisplay = panel_fixed_mode->vdisplay;
305 		adjusted_mode->vsync_start = panel_fixed_mode->vsync_start;
306 		adjusted_mode->vsync_end = panel_fixed_mode->vsync_end;
307 		adjusted_mode->vtotal = panel_fixed_mode->vtotal;
308 		adjusted_mode->clock = panel_fixed_mode->clock;
309 		drm_mode_set_crtcinfo(adjusted_mode,
310 				      CRTC_INTERLACE_HALVE_V);
311 	}
312 
313 	/*
314 	 * XXX: It would be nice to support lower refresh rates on the
315 	 * panels to reduce power consumption, and perhaps match the
316 	 * user's requested refresh rate.
317 	 */
318 
319 	return true;
320 }
321 
322 static void cdv_intel_lvds_prepare(struct drm_encoder *encoder)
323 {
324 	struct drm_device *dev = encoder->dev;
325 	struct drm_psb_private *dev_priv = dev->dev_private;
326 	struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
327 
328 	if (!gma_power_begin(dev, true))
329 		return;
330 
331 	mode_dev->saveBLC_PWM_CTL = REG_READ(BLC_PWM_CTL);
332 	mode_dev->backlight_duty_cycle = (mode_dev->saveBLC_PWM_CTL &
333 					  BACKLIGHT_DUTY_CYCLE_MASK);
334 
335 	cdv_intel_lvds_set_power(dev, encoder, false);
336 
337 	gma_power_end(dev);
338 }
339 
340 static void cdv_intel_lvds_commit(struct drm_encoder *encoder)
341 {
342 	struct drm_device *dev = encoder->dev;
343 	struct drm_psb_private *dev_priv = dev->dev_private;
344 	struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
345 
346 	if (mode_dev->backlight_duty_cycle == 0)
347 		mode_dev->backlight_duty_cycle =
348 		    cdv_intel_lvds_get_max_backlight(dev);
349 
350 	cdv_intel_lvds_set_power(dev, encoder, true);
351 }
352 
353 static void cdv_intel_lvds_mode_set(struct drm_encoder *encoder,
354 				struct drm_display_mode *mode,
355 				struct drm_display_mode *adjusted_mode)
356 {
357 	struct drm_device *dev = encoder->dev;
358 	struct drm_psb_private *dev_priv = dev->dev_private;
359 	struct psb_intel_crtc *psb_intel_crtc = to_psb_intel_crtc(
360 							encoder->crtc);
361 	u32 pfit_control;
362 
363 	/*
364 	 * The LVDS pin pair will already have been turned on in the
365 	 * cdv_intel_crtc_mode_set since it has a large impact on the DPLL
366 	 * settings.
367 	 */
368 
369 	/*
370 	 * Enable automatic panel scaling so that non-native modes fill the
371 	 * screen.  Should be enabled before the pipe is enabled, according to
372 	 * register description and PRM.
373 	 */
374 	if (mode->hdisplay != adjusted_mode->hdisplay ||
375 	    mode->vdisplay != adjusted_mode->vdisplay)
376 		pfit_control = (PFIT_ENABLE | VERT_AUTO_SCALE |
377 				HORIZ_AUTO_SCALE | VERT_INTERP_BILINEAR |
378 				HORIZ_INTERP_BILINEAR);
379 	else
380 		pfit_control = 0;
381 
382 	pfit_control |= psb_intel_crtc->pipe << PFIT_PIPE_SHIFT;
383 
384 	if (dev_priv->lvds_dither)
385 		pfit_control |= PANEL_8TO6_DITHER_ENABLE;
386 
387 	REG_WRITE(PFIT_CONTROL, pfit_control);
388 }
389 
390 /**
391  * Detect the LVDS connection.
392  *
393  * This always returns CONNECTOR_STATUS_CONNECTED.
394  * This connector should only have
395  * been set up if the LVDS was actually connected anyway.
396  */
397 static enum drm_connector_status cdv_intel_lvds_detect(
398 				struct drm_connector *connector, bool force)
399 {
400 	return connector_status_connected;
401 }
402 
403 /**
404  * Return the list of DDC modes if available, or the BIOS fixed mode otherwise.
405  */
406 static int cdv_intel_lvds_get_modes(struct drm_connector *connector)
407 {
408 	struct drm_device *dev = connector->dev;
409 	struct drm_psb_private *dev_priv = dev->dev_private;
410 	struct psb_intel_encoder *psb_intel_encoder =
411 					psb_intel_attached_encoder(connector);
412 	struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
413 	int ret;
414 
415 	ret = psb_intel_ddc_get_modes(connector, &psb_intel_encoder->i2c_bus->adapter);
416 
417 	if (ret)
418 		return ret;
419 
420 	/* Didn't get an EDID, so
421 	 * Set wide sync ranges so we get all modes
422 	 * handed to valid_mode for checking
423 	 */
424 	connector->display_info.min_vfreq = 0;
425 	connector->display_info.max_vfreq = 200;
426 	connector->display_info.min_hfreq = 0;
427 	connector->display_info.max_hfreq = 200;
428 	if (mode_dev->panel_fixed_mode != NULL) {
429 		struct drm_display_mode *mode =
430 		    drm_mode_duplicate(dev, mode_dev->panel_fixed_mode);
431 		drm_mode_probed_add(connector, mode);
432 		return 1;
433 	}
434 
435 	return 0;
436 }
437 
438 /**
439  * cdv_intel_lvds_destroy - unregister and free LVDS structures
440  * @connector: connector to free
441  *
442  * Unregister the DDC bus for this connector then free the driver private
443  * structure.
444  */
445 static void cdv_intel_lvds_destroy(struct drm_connector *connector)
446 {
447 	struct psb_intel_encoder *psb_intel_encoder =
448 					psb_intel_attached_encoder(connector);
449 
450 	if (psb_intel_encoder->i2c_bus)
451 		psb_intel_i2c_destroy(psb_intel_encoder->i2c_bus);
452 	drm_sysfs_connector_remove(connector);
453 	drm_connector_cleanup(connector);
454 	kfree(connector);
455 }
456 
457 static int cdv_intel_lvds_set_property(struct drm_connector *connector,
458 				       struct drm_property *property,
459 				       uint64_t value)
460 {
461 	struct drm_encoder *encoder = connector->encoder;
462 
463 	if (!strcmp(property->name, "scaling mode") && encoder) {
464 		struct psb_intel_crtc *crtc =
465 					to_psb_intel_crtc(encoder->crtc);
466 		uint64_t curValue;
467 
468 		if (!crtc)
469 			return -1;
470 
471 		switch (value) {
472 		case DRM_MODE_SCALE_FULLSCREEN:
473 			break;
474 		case DRM_MODE_SCALE_NO_SCALE:
475 			break;
476 		case DRM_MODE_SCALE_ASPECT:
477 			break;
478 		default:
479 			return -1;
480 		}
481 
482 		if (drm_object_property_get_value(&connector->base,
483 						     property,
484 						     &curValue))
485 			return -1;
486 
487 		if (curValue == value)
488 			return 0;
489 
490 		if (drm_object_property_set_value(&connector->base,
491 							property,
492 							value))
493 			return -1;
494 
495 		if (crtc->saved_mode.hdisplay != 0 &&
496 		    crtc->saved_mode.vdisplay != 0) {
497 			if (!drm_crtc_helper_set_mode(encoder->crtc,
498 						      &crtc->saved_mode,
499 						      encoder->crtc->x,
500 						      encoder->crtc->y,
501 						      encoder->crtc->fb))
502 				return -1;
503 		}
504 	} else if (!strcmp(property->name, "backlight") && encoder) {
505 		if (drm_object_property_set_value(&connector->base,
506 							property,
507 							value))
508 			return -1;
509 		else
510                         gma_backlight_set(encoder->dev, value);
511 	} else if (!strcmp(property->name, "DPMS") && encoder) {
512 		struct drm_encoder_helper_funcs *helpers =
513 					encoder->helper_private;
514 		helpers->dpms(encoder, value);
515 	}
516 	return 0;
517 }
518 
519 static const struct drm_encoder_helper_funcs
520 					cdv_intel_lvds_helper_funcs = {
521 	.dpms = cdv_intel_lvds_encoder_dpms,
522 	.mode_fixup = cdv_intel_lvds_mode_fixup,
523 	.prepare = cdv_intel_lvds_prepare,
524 	.mode_set = cdv_intel_lvds_mode_set,
525 	.commit = cdv_intel_lvds_commit,
526 };
527 
528 static const struct drm_connector_helper_funcs
529 				cdv_intel_lvds_connector_helper_funcs = {
530 	.get_modes = cdv_intel_lvds_get_modes,
531 	.mode_valid = cdv_intel_lvds_mode_valid,
532 	.best_encoder = psb_intel_best_encoder,
533 };
534 
535 static const struct drm_connector_funcs cdv_intel_lvds_connector_funcs = {
536 	.dpms = drm_helper_connector_dpms,
537 	.save = cdv_intel_lvds_save,
538 	.restore = cdv_intel_lvds_restore,
539 	.detect = cdv_intel_lvds_detect,
540 	.fill_modes = drm_helper_probe_single_connector_modes,
541 	.set_property = cdv_intel_lvds_set_property,
542 	.destroy = cdv_intel_lvds_destroy,
543 };
544 
545 
546 static void cdv_intel_lvds_enc_destroy(struct drm_encoder *encoder)
547 {
548 	drm_encoder_cleanup(encoder);
549 }
550 
551 static const struct drm_encoder_funcs cdv_intel_lvds_enc_funcs = {
552 	.destroy = cdv_intel_lvds_enc_destroy,
553 };
554 
555 /*
556  * Enumerate the child dev array parsed from VBT to check whether
557  * the LVDS is present.
558  * If it is present, return 1.
559  * If it is not present, return false.
560  * If no child dev is parsed from VBT, it assumes that the LVDS is present.
561  */
562 static bool lvds_is_present_in_vbt(struct drm_device *dev,
563 				   u8 *i2c_pin)
564 {
565 	struct drm_psb_private *dev_priv = dev->dev_private;
566 	int i;
567 
568 	if (!dev_priv->child_dev_num)
569 		return true;
570 
571 	for (i = 0; i < dev_priv->child_dev_num; i++) {
572 		struct child_device_config *child = dev_priv->child_dev + i;
573 
574 		/* If the device type is not LFP, continue.
575 		 * We have to check both the new identifiers as well as the
576 		 * old for compatibility with some BIOSes.
577 		 */
578 		if (child->device_type != DEVICE_TYPE_INT_LFP &&
579 		    child->device_type != DEVICE_TYPE_LFP)
580 			continue;
581 
582 		if (child->i2c_pin)
583 		    *i2c_pin = child->i2c_pin;
584 
585 		/* However, we cannot trust the BIOS writers to populate
586 		 * the VBT correctly.  Since LVDS requires additional
587 		 * information from AIM blocks, a non-zero addin offset is
588 		 * a good indicator that the LVDS is actually present.
589 		 */
590 		if (child->addin_offset)
591 			return true;
592 
593 		/* But even then some BIOS writers perform some black magic
594 		 * and instantiate the device without reference to any
595 		 * additional data.  Trust that if the VBT was written into
596 		 * the OpRegion then they have validated the LVDS's existence.
597 		 */
598 		if (dev_priv->opregion.vbt)
599 			return true;
600 	}
601 
602 	return false;
603 }
604 
605 /**
606  * cdv_intel_lvds_init - setup LVDS connectors on this device
607  * @dev: drm device
608  *
609  * Create the connector, register the LVDS DDC bus, and try to figure out what
610  * modes we can display on the LVDS panel (if present).
611  */
612 void cdv_intel_lvds_init(struct drm_device *dev,
613 		     struct psb_intel_mode_device *mode_dev)
614 {
615 	struct psb_intel_encoder *psb_intel_encoder;
616 	struct psb_intel_connector *psb_intel_connector;
617 	struct cdv_intel_lvds_priv *lvds_priv;
618 	struct drm_connector *connector;
619 	struct drm_encoder *encoder;
620 	struct drm_display_mode *scan;
621 	struct drm_crtc *crtc;
622 	struct drm_psb_private *dev_priv = dev->dev_private;
623 	u32 lvds;
624 	int pipe;
625 	u8 pin;
626 
627 	pin = GMBUS_PORT_PANEL;
628 	if (!lvds_is_present_in_vbt(dev, &pin)) {
629 		DRM_DEBUG_KMS("LVDS is not present in VBT\n");
630 		return;
631 	}
632 
633 	psb_intel_encoder = kzalloc(sizeof(struct psb_intel_encoder),
634 				    GFP_KERNEL);
635 	if (!psb_intel_encoder)
636 		return;
637 
638 	psb_intel_connector = kzalloc(sizeof(struct psb_intel_connector),
639 				      GFP_KERNEL);
640 	if (!psb_intel_connector)
641 		goto failed_connector;
642 
643 	lvds_priv = kzalloc(sizeof(struct cdv_intel_lvds_priv), GFP_KERNEL);
644 	if (!lvds_priv)
645 		goto failed_lvds_priv;
646 
647 	psb_intel_encoder->dev_priv = lvds_priv;
648 
649 	connector = &psb_intel_connector->base;
650 	encoder = &psb_intel_encoder->base;
651 
652 
653 	drm_connector_init(dev, connector,
654 			   &cdv_intel_lvds_connector_funcs,
655 			   DRM_MODE_CONNECTOR_LVDS);
656 
657 	drm_encoder_init(dev, encoder,
658 			 &cdv_intel_lvds_enc_funcs,
659 			 DRM_MODE_ENCODER_LVDS);
660 
661 
662 	psb_intel_connector_attach_encoder(psb_intel_connector,
663 					   psb_intel_encoder);
664 	psb_intel_encoder->type = INTEL_OUTPUT_LVDS;
665 
666 	drm_encoder_helper_add(encoder, &cdv_intel_lvds_helper_funcs);
667 	drm_connector_helper_add(connector,
668 				 &cdv_intel_lvds_connector_helper_funcs);
669 	connector->display_info.subpixel_order = SubPixelHorizontalRGB;
670 	connector->interlace_allowed = false;
671 	connector->doublescan_allowed = false;
672 
673 	/*Attach connector properties*/
674 	drm_object_attach_property(&connector->base,
675 				      dev->mode_config.scaling_mode_property,
676 				      DRM_MODE_SCALE_FULLSCREEN);
677 	drm_object_attach_property(&connector->base,
678 				      dev_priv->backlight_property,
679 				      BRIGHTNESS_MAX_LEVEL);
680 
681 	/**
682 	 * Set up I2C bus
683 	 * FIXME: distroy i2c_bus when exit
684 	 */
685 	psb_intel_encoder->i2c_bus = psb_intel_i2c_create(dev,
686 							 GPIOB,
687 							 "LVDSBLC_B");
688 	if (!psb_intel_encoder->i2c_bus) {
689 		dev_printk(KERN_ERR,
690 			&dev->pdev->dev, "I2C bus registration failed.\n");
691 		goto failed_blc_i2c;
692 	}
693 	psb_intel_encoder->i2c_bus->slave_addr = 0x2C;
694 	dev_priv->lvds_i2c_bus = psb_intel_encoder->i2c_bus;
695 
696 	/*
697 	 * LVDS discovery:
698 	 * 1) check for EDID on DDC
699 	 * 2) check for VBT data
700 	 * 3) check to see if LVDS is already on
701 	 *    if none of the above, no panel
702 	 * 4) make sure lid is open
703 	 *    if closed, act like it's not there for now
704 	 */
705 
706 	/* Set up the DDC bus. */
707 	psb_intel_encoder->ddc_bus = psb_intel_i2c_create(dev,
708 							 GPIOC,
709 							 "LVDSDDC_C");
710 	if (!psb_intel_encoder->ddc_bus) {
711 		dev_printk(KERN_ERR, &dev->pdev->dev,
712 			   "DDC bus registration " "failed.\n");
713 		goto failed_ddc;
714 	}
715 
716 	/*
717 	 * Attempt to get the fixed panel mode from DDC.  Assume that the
718 	 * preferred mode is the right one.
719 	 */
720 	psb_intel_ddc_get_modes(connector,
721 				&psb_intel_encoder->ddc_bus->adapter);
722 	list_for_each_entry(scan, &connector->probed_modes, head) {
723 		if (scan->type & DRM_MODE_TYPE_PREFERRED) {
724 			mode_dev->panel_fixed_mode =
725 			    drm_mode_duplicate(dev, scan);
726 			goto out;	/* FIXME: check for quirks */
727 		}
728 	}
729 
730 	/* Failed to get EDID, what about VBT? do we need this?*/
731 	if (dev_priv->lfp_lvds_vbt_mode) {
732 		mode_dev->panel_fixed_mode =
733 			drm_mode_duplicate(dev, dev_priv->lfp_lvds_vbt_mode);
734 		if (mode_dev->panel_fixed_mode) {
735 			mode_dev->panel_fixed_mode->type |=
736 				DRM_MODE_TYPE_PREFERRED;
737 			goto out;	/* FIXME: check for quirks */
738 		}
739 	}
740 	/*
741 	 * If we didn't get EDID, try checking if the panel is already turned
742 	 * on.	If so, assume that whatever is currently programmed is the
743 	 * correct mode.
744 	 */
745 	lvds = REG_READ(LVDS);
746 	pipe = (lvds & LVDS_PIPEB_SELECT) ? 1 : 0;
747 	crtc = psb_intel_get_crtc_from_pipe(dev, pipe);
748 
749 	if (crtc && (lvds & LVDS_PORT_EN)) {
750 		mode_dev->panel_fixed_mode =
751 		    cdv_intel_crtc_mode_get(dev, crtc);
752 		if (mode_dev->panel_fixed_mode) {
753 			mode_dev->panel_fixed_mode->type |=
754 			    DRM_MODE_TYPE_PREFERRED;
755 			goto out;	/* FIXME: check for quirks */
756 		}
757 	}
758 
759 	/* If we still don't have a mode after all that, give up. */
760 	if (!mode_dev->panel_fixed_mode) {
761 		DRM_DEBUG
762 			("Found no modes on the lvds, ignoring the LVDS\n");
763 		goto failed_find;
764 	}
765 
766 	/* setup PWM */
767 	{
768 		u32 pwm;
769 
770 		pwm = REG_READ(BLC_PWM_CTL2);
771 		if (pipe == 1)
772 			pwm |= PWM_PIPE_B;
773 		else
774 			pwm &= ~PWM_PIPE_B;
775 		pwm |= PWM_ENABLE;
776 		REG_WRITE(BLC_PWM_CTL2, pwm);
777 	}
778 
779 out:
780 	drm_sysfs_connector_add(connector);
781 	return;
782 
783 failed_find:
784 	printk(KERN_ERR "Failed find\n");
785 	if (psb_intel_encoder->ddc_bus)
786 		psb_intel_i2c_destroy(psb_intel_encoder->ddc_bus);
787 failed_ddc:
788 	printk(KERN_ERR "Failed DDC\n");
789 	if (psb_intel_encoder->i2c_bus)
790 		psb_intel_i2c_destroy(psb_intel_encoder->i2c_bus);
791 failed_blc_i2c:
792 	printk(KERN_ERR "Failed BLC\n");
793 	drm_encoder_cleanup(encoder);
794 	drm_connector_cleanup(connector);
795 	kfree(lvds_priv);
796 failed_lvds_priv:
797 	kfree(psb_intel_connector);
798 failed_connector:
799 	kfree(psb_intel_encoder);
800 }
801