drivers/gpu/drm/gma500/cdv_intel_lvds.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright © 2006-2011 Intel Corporation
   4  *
   5  * Authors:
   6  *      Eric Anholt <eric@anholt.net>
   7  *      Dave Airlie <airlied@linux.ie>
   8  *      Jesse Barnes <jesse.barnes@intel.com>
   9  */
  10
  11 #include <linux/dmi.h>
  12 #include <linux/i2c.h>
  13 #include <linux/pm_runtime.h>
  14
  15 #include <drm/drm_simple_kms_helper.h>
  16
  17 #include "cdv_device.h"
  18 #include "intel_bios.h"
  19 #include "power.h"
  20 #include "psb_drv.h"
  21 #include "psb_intel_drv.h"
  22 #include "psb_intel_reg.h"
  23
  24 /*
  25  * LVDS I2C backlight control macros
  26  */
  27 #define BRIGHTNESS_MAX_LEVEL 100
  28 #define BRIGHTNESS_MASK 0xFF
  29 #define BLC_I2C_TYPE    0x01
  30 #define BLC_PWM_TYPT    0x02
  31
  32 #define BLC_POLARITY_NORMAL 0
  33 #define BLC_POLARITY_INVERSE 1
  34
  35 #define PSB_BLC_MAX_PWM_REG_FREQ       (0xFFFE)
  36 #define PSB_BLC_MIN_PWM_REG_FREQ        (0x2)
  37 #define PSB_BLC_PWM_PRECISION_FACTOR    (10)
  38 #define PSB_BACKLIGHT_PWM_CTL_SHIFT     (16)
  39 #define PSB_BACKLIGHT_PWM_POLARITY_BIT_CLEAR (0xFFFE)
  40
  41 struct cdv_intel_lvds_priv {
  42         /**
  43          * Saved LVDO output states
  44          */
  45         uint32_t savePP_ON;
  46         uint32_t savePP_OFF;
  47         uint32_t saveLVDS;
  48         uint32_t savePP_CONTROL;
  49         uint32_t savePP_CYCLE;
  50         uint32_t savePFIT_CONTROL;
  51         uint32_t savePFIT_PGM_RATIOS;
  52         uint32_t saveBLC_PWM_CTL;
  53 };
  54
  55 /*
  56  * Returns the maximum level of the backlight duty cycle field.
  57  */
  58 static u32 cdv_intel_lvds_get_max_backlight(struct drm_device *dev)
  59 {
  60         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
  61         u32 retval;
  62
  63         if (gma_power_begin(dev, false)) {
  64                 retval = ((REG_READ(BLC_PWM_CTL) &
  65                           BACKLIGHT_MODULATION_FREQ_MASK) >>
  66                           BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
  67
  68                 gma_power_end(dev);
  69         } else
  70                 retval = ((dev_priv->regs.saveBLC_PWM_CTL &
  71                           BACKLIGHT_MODULATION_FREQ_MASK) >>
  72                           BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
  73
  74         return retval;
  75 }
  76
  77 /*
  78  * Sets the backlight level.
  79  *
  80  * level backlight level, from 0 to cdv_intel_lvds_get_max_backlight().
  81  */
  82 static void cdv_intel_lvds_set_backlight(struct drm_device *dev, int level)
  83 {
  84         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
  85         u32 blc_pwm_ctl;
  86
  87         if (gma_power_begin(dev, false)) {
  88                 blc_pwm_ctl =
  89                         REG_READ(BLC_PWM_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
  90                 REG_WRITE(BLC_PWM_CTL,
  91                                 (blc_pwm_ctl |
  92                                 (level << BACKLIGHT_DUTY_CYCLE_SHIFT)));
  93                 gma_power_end(dev);
  94         } else {
  95                 blc_pwm_ctl = dev_priv->regs.saveBLC_PWM_CTL &
  96                                 ~BACKLIGHT_DUTY_CYCLE_MASK;
  97                 dev_priv->regs.saveBLC_PWM_CTL = (blc_pwm_ctl |
  98                                         (level << BACKLIGHT_DUTY_CYCLE_SHIFT));
  99         }
 100 }
 101
 102 /*
 103  * Sets the power state for the panel.
 104  */
 105 static void cdv_intel_lvds_set_power(struct drm_device *dev,
 106                                      struct drm_encoder *encoder, bool on)
 107 {
 108         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
 109         u32 pp_status;
 110
 111         if (!gma_power_begin(dev, true))
 112                 return;
 113
 114         if (on) {
 115                 REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) |
 116                           POWER_TARGET_ON);
 117                 do {
 118                         pp_status = REG_READ(PP_STATUS);
 119                 } while ((pp_status & PP_ON) == 0);
 120
 121                 cdv_intel_lvds_set_backlight(dev,
 122                                 dev_priv->mode_dev.backlight_duty_cycle);
 123         } else {
 124                 cdv_intel_lvds_set_backlight(dev, 0);
 125
 126                 REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) &
 127                           ~POWER_TARGET_ON);
 128                 do {
 129                         pp_status = REG_READ(PP_STATUS);
 130                 } while (pp_status & PP_ON);
 131         }
 132         gma_power_end(dev);
 133 }
 134
 135 static void cdv_intel_lvds_encoder_dpms(struct drm_encoder *encoder, int mode)
 136 {
 137         struct drm_device *dev = encoder->dev;
 138         if (mode == DRM_MODE_DPMS_ON)
 139                 cdv_intel_lvds_set_power(dev, encoder, true);
 140         else
 141                 cdv_intel_lvds_set_power(dev, encoder, false);
 142         /* XXX: We never power down the LVDS pairs. */
 143 }
 144
 145 static void cdv_intel_lvds_save(struct drm_connector *connector)
 146 {
 147 }
 148
 149 static void cdv_intel_lvds_restore(struct drm_connector *connector)
 150 {
 151 }
 152
 153 static enum drm_mode_status cdv_intel_lvds_mode_valid(struct drm_connector *connector,
 154                               struct drm_display_mode *mode)
 155 {
 156         struct drm_device *dev = connector->dev;
 157         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
 158         struct drm_display_mode *fixed_mode =
 159                                         dev_priv->mode_dev.panel_fixed_mode;
 160
 161         /* just in case */
 162         if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
 163                 return MODE_NO_DBLESCAN;
 164
 165         /* just in case */
 166         if (mode->flags & DRM_MODE_FLAG_INTERLACE)
 167                 return MODE_NO_INTERLACE;
 168
 169         if (fixed_mode) {
 170                 if (mode->hdisplay > fixed_mode->hdisplay)
 171                         return MODE_PANEL;
 172                 if (mode->vdisplay > fixed_mode->vdisplay)
 173                         return MODE_PANEL;
 174         }
 175         return MODE_OK;
 176 }
 177
 178 static bool cdv_intel_lvds_mode_fixup(struct drm_encoder *encoder,
 179                                   const struct drm_display_mode *mode,
 180                                   struct drm_display_mode *adjusted_mode)
 181 {
 182         struct drm_device *dev = encoder->dev;
 183         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
 184         struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
 185         struct drm_encoder *tmp_encoder;
 186         struct drm_display_mode *panel_fixed_mode = mode_dev->panel_fixed_mode;
 187
 188         /* Should never happen!! */
 189         list_for_each_entry(tmp_encoder, &dev->mode_config.encoder_list,
 190                             head) {
 191                 if (tmp_encoder != encoder
 192                     && tmp_encoder->crtc == encoder->crtc) {
 193                         pr_err("Can't enable LVDS and another encoder on the same pipe\n");
 194                         return false;
 195                 }
 196         }
 197
 198         /*
 199          * If we have timings from the BIOS for the panel, put them in
 200          * to the adjusted mode.  The CRTC will be set up for this mode,
 201          * with the panel scaling set up to source from the H/VDisplay
 202          * of the original mode.
 203          */
 204         if (panel_fixed_mode != NULL) {
 205                 adjusted_mode->hdisplay = panel_fixed_mode->hdisplay;
 206                 adjusted_mode->hsync_start = panel_fixed_mode->hsync_start;
 207                 adjusted_mode->hsync_end = panel_fixed_mode->hsync_end;
 208                 adjusted_mode->htotal = panel_fixed_mode->htotal;
 209                 adjusted_mode->vdisplay = panel_fixed_mode->vdisplay;
 210                 adjusted_mode->vsync_start = panel_fixed_mode->vsync_start;
 211                 adjusted_mode->vsync_end = panel_fixed_mode->vsync_end;
 212                 adjusted_mode->vtotal = panel_fixed_mode->vtotal;
 213                 adjusted_mode->clock = panel_fixed_mode->clock;
 214                 drm_mode_set_crtcinfo(adjusted_mode,
 215                                       CRTC_INTERLACE_HALVE_V);
 216         }
 217
 218         /*
 219          * XXX: It would be nice to support lower refresh rates on the
 220          * panels to reduce power consumption, and perhaps match the
 221          * user's requested refresh rate.
 222          */
 223
 224         return true;
 225 }
 226
 227 static void cdv_intel_lvds_prepare(struct drm_encoder *encoder)
 228 {
 229         struct drm_device *dev = encoder->dev;
 230         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
 231         struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
 232
 233         if (!gma_power_begin(dev, true))
 234                 return;
 235
 236         mode_dev->saveBLC_PWM_CTL = REG_READ(BLC_PWM_CTL);
 237         mode_dev->backlight_duty_cycle = (mode_dev->saveBLC_PWM_CTL &
 238                                           BACKLIGHT_DUTY_CYCLE_MASK);
 239
 240         cdv_intel_lvds_set_power(dev, encoder, false);
 241
 242         gma_power_end(dev);
 243 }
 244
 245 static void cdv_intel_lvds_commit(struct drm_encoder *encoder)
 246 {
 247         struct drm_device *dev = encoder->dev;
 248         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
 249         struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
 250
 251         if (mode_dev->backlight_duty_cycle == 0)
 252                 mode_dev->backlight_duty_cycle =
 253                     cdv_intel_lvds_get_max_backlight(dev);
 254
 255         cdv_intel_lvds_set_power(dev, encoder, true);
 256 }
 257
 258 static void cdv_intel_lvds_mode_set(struct drm_encoder *encoder,
 259                                 struct drm_display_mode *mode,
 260                                 struct drm_display_mode *adjusted_mode)
 261 {
 262         struct drm_device *dev = encoder->dev;
 263         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
 264         struct gma_crtc *gma_crtc = to_gma_crtc(encoder->crtc);
 265         u32 pfit_control;
 266
 267         /*
 268          * The LVDS pin pair will already have been turned on in the
 269          * cdv_intel_crtc_mode_set since it has a large impact on the DPLL
 270          * settings.
 271          */
 272
 273         /*
 274          * Enable automatic panel scaling so that non-native modes fill the
 275          * screen.  Should be enabled before the pipe is enabled, according to
 276          * register description and PRM.
 277          */
 278         if (mode->hdisplay != adjusted_mode->hdisplay ||
 279             mode->vdisplay != adjusted_mode->vdisplay)
 280                 pfit_control = (PFIT_ENABLE | VERT_AUTO_SCALE |
 281                                 HORIZ_AUTO_SCALE | VERT_INTERP_BILINEAR |
 282                                 HORIZ_INTERP_BILINEAR);
 283         else
 284                 pfit_control = 0;
 285
 286         pfit_control |= gma_crtc->pipe << PFIT_PIPE_SHIFT;
 287
 288         if (dev_priv->lvds_dither)
 289                 pfit_control |= PANEL_8TO6_DITHER_ENABLE;
 290
 291         REG_WRITE(PFIT_CONTROL, pfit_control);
 292 }
 293
 294 /*
 295  * Return the list of DDC modes if available, or the BIOS fixed mode otherwise.
 296  */
 297 static int cdv_intel_lvds_get_modes(struct drm_connector *connector)
 298 {
 299         struct drm_device *dev = connector->dev;
 300         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
 301         struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
 302         int ret;
 303
 304         ret = psb_intel_ddc_get_modes(connector, connector->ddc);
 305
 306         if (ret)
 307                 return ret;
 308
 309         if (mode_dev->panel_fixed_mode != NULL) {
 310                 struct drm_display_mode *mode =
 311                     drm_mode_duplicate(dev, mode_dev->panel_fixed_mode);
 312                 drm_mode_probed_add(connector, mode);
 313                 return 1;
 314         }
 315
 316         return 0;
 317 }
 318
 319 static void cdv_intel_lvds_destroy(struct drm_connector *connector)
 320 {
 321         struct gma_connector *gma_connector = to_gma_connector(connector);
 322         struct gma_encoder *gma_encoder = gma_attached_encoder(connector);
 323
 324         gma_i2c_destroy(to_gma_i2c_chan(connector->ddc));
 325         gma_i2c_destroy(gma_encoder->i2c_bus);
 326         drm_connector_cleanup(connector);
 327         kfree(gma_connector);
 328 }
 329
 330 static int cdv_intel_lvds_set_property(struct drm_connector *connector,
 331                                        struct drm_property *property,
 332                                        uint64_t value)
 333 {
 334         struct drm_encoder *encoder = connector->encoder;
 335
 336         if (!strcmp(property->name, "scaling mode") && encoder) {
 337                 struct gma_crtc *crtc = to_gma_crtc(encoder->crtc);
 338                 uint64_t curValue;
 339
 340                 if (!crtc)
 341                         return -1;
 342
 343                 switch (value) {
 344                 case DRM_MODE_SCALE_FULLSCREEN:
 345                         break;
 346                 case DRM_MODE_SCALE_NO_SCALE:
 347                         break;
 348                 case DRM_MODE_SCALE_ASPECT:
 349                         break;
 350                 default:
 351                         return -1;
 352                 }
 353
 354                 if (drm_object_property_get_value(&connector->base,
 355                                                      property,
 356                                                      &curValue))
 357                         return -1;
 358
 359                 if (curValue == value)
 360                         return 0;
 361
 362                 if (drm_object_property_set_value(&connector->base,
 363                                                         property,
 364                                                         value))
 365                         return -1;
 366
 367                 if (crtc->saved_mode.hdisplay != 0 &&
 368                     crtc->saved_mode.vdisplay != 0) {
 369                         if (!drm_crtc_helper_set_mode(encoder->crtc,
 370                                                       &crtc->saved_mode,
 371                                                       encoder->crtc->x,
 372                                                       encoder->crtc->y,
 373                                                       encoder->crtc->primary->fb))
 374                                 return -1;
 375                 }
 376         } else if (!strcmp(property->name, "backlight") && encoder) {
 377                 if (drm_object_property_set_value(&connector->base,
 378                                                         property,
 379                                                         value))
 380                         return -1;
 381                 else
 382                         gma_backlight_set(encoder->dev, value);
 383         } else if (!strcmp(property->name, "DPMS") && encoder) {
 384                 const struct drm_encoder_helper_funcs *helpers =
 385                                         encoder->helper_private;
 386                 helpers->dpms(encoder, value);
 387         }
 388         return 0;
 389 }
 390
 391 static const struct drm_encoder_helper_funcs
 392                                         cdv_intel_lvds_helper_funcs = {
 393         .dpms = cdv_intel_lvds_encoder_dpms,
 394         .mode_fixup = cdv_intel_lvds_mode_fixup,
 395         .prepare = cdv_intel_lvds_prepare,
 396         .mode_set = cdv_intel_lvds_mode_set,
 397         .commit = cdv_intel_lvds_commit,
 398 };
 399
 400 static const struct drm_connector_helper_funcs
 401                                 cdv_intel_lvds_connector_helper_funcs = {
 402         .get_modes = cdv_intel_lvds_get_modes,
 403         .mode_valid = cdv_intel_lvds_mode_valid,
 404         .best_encoder = gma_best_encoder,
 405 };
 406
 407 static const struct drm_connector_funcs cdv_intel_lvds_connector_funcs = {
 408         .dpms = drm_helper_connector_dpms,
 409         .fill_modes = drm_helper_probe_single_connector_modes,
 410         .set_property = cdv_intel_lvds_set_property,
 411         .destroy = cdv_intel_lvds_destroy,
 412 };
 413
 414 /*
 415  * Enumerate the child dev array parsed from VBT to check whether
 416  * the LVDS is present.
 417  * If it is present, return 1.
 418  * If it is not present, return false.
 419  * If no child dev is parsed from VBT, it assumes that the LVDS is present.
 420  */
 421 static bool lvds_is_present_in_vbt(struct drm_device *dev,
 422                                    u8 *i2c_pin)
 423 {
 424         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
 425         int i;
 426
 427         if (!dev_priv->child_dev_num)
 428                 return true;
 429
 430         for (i = 0; i < dev_priv->child_dev_num; i++) {
 431                 struct child_device_config *child = dev_priv->child_dev + i;
 432
 433                 /* If the device type is not LFP, continue.
 434                  * We have to check both the new identifiers as well as the
 435                  * old for compatibility with some BIOSes.
 436                  */
 437                 if (child->device_type != DEVICE_TYPE_INT_LFP &&
 438                     child->device_type != DEVICE_TYPE_LFP)
 439                         continue;
 440
 441                 if (child->i2c_pin)
 442                     *i2c_pin = child->i2c_pin;
 443
 444                 /* However, we cannot trust the BIOS writers to populate
 445                  * the VBT correctly.  Since LVDS requires additional
 446                  * information from AIM blocks, a non-zero addin offset is
 447                  * a good indicator that the LVDS is actually present.
 448                  */
 449                 if (child->addin_offset)
 450                         return true;
 451
 452                 /* But even then some BIOS writers perform some black magic
 453                  * and instantiate the device without reference to any
 454                  * additional data.  Trust that if the VBT was written into
 455                  * the OpRegion then they have validated the LVDS's existence.
 456                  */
 457                 if (dev_priv->opregion.vbt)
 458                         return true;
 459         }
 460
 461         return false;
 462 }
 463
 464 /**
 465  * cdv_intel_lvds_init - setup LVDS connectors on this device
 466  * @dev: drm device
 467  * @mode_dev: PSB mode device
 468  *
 469  * Create the connector, register the LVDS DDC bus, and try to figure out what
 470  * modes we can display on the LVDS panel (if present).
 471  */
 472 void cdv_intel_lvds_init(struct drm_device *dev,
 473                      struct psb_intel_mode_device *mode_dev)
 474 {
 475         struct gma_encoder *gma_encoder;
 476         struct gma_connector *gma_connector;
 477         struct cdv_intel_lvds_priv *lvds_priv;
 478         struct drm_connector *connector;
 479         struct drm_encoder *encoder;
 480         struct drm_display_mode *scan;
 481         struct drm_crtc *crtc;
 482         struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
 483         struct gma_i2c_chan *ddc_bus;
 484         u32 lvds;
 485         int pipe;
 486         int ret;
 487         u8 pin;
 488
 489         if (!dev_priv->lvds_enabled_in_vbt)
 490                 return;
 491
 492         pin = GMBUS_PORT_PANEL;
 493         if (!lvds_is_present_in_vbt(dev, &pin)) {
 494                 DRM_DEBUG_KMS("LVDS is not present in VBT\n");
 495                 return;
 496         }
 497
 498         gma_encoder = kzalloc(sizeof(struct gma_encoder),
 499                                     GFP_KERNEL);
 500         if (!gma_encoder)
 501                 return;
 502
 503         gma_connector = kzalloc(sizeof(struct gma_connector),
 504                                       GFP_KERNEL);
 505         if (!gma_connector)
 506                 goto err_free_encoder;
 507
 508         lvds_priv = kzalloc(sizeof(struct cdv_intel_lvds_priv), GFP_KERNEL);
 509         if (!lvds_priv)
 510                 goto err_free_connector;
 511
 512         gma_encoder->dev_priv = lvds_priv;
 513
 514         connector = &gma_connector->base;
 515         gma_connector->save = cdv_intel_lvds_save;
 516         gma_connector->restore = cdv_intel_lvds_restore;
 517         encoder = &gma_encoder->base;
 518
 519         /* Set up the DDC bus. */
 520         ddc_bus = gma_i2c_create(dev, GPIOC, "LVDSDDC_C");
 521         if (!ddc_bus) {
 522                 dev_printk(KERN_ERR, dev->dev,
 523                            "DDC bus registration " "failed.\n");
 524                 goto err_free_lvds_priv;
 525         }
 526
 527         ret = drm_connector_init_with_ddc(dev, connector,
 528                                           &cdv_intel_lvds_connector_funcs,
 529                                           DRM_MODE_CONNECTOR_LVDS,
 530                                           &ddc_bus->base);
 531         if (ret)
 532                 goto err_destroy_ddc;
 533
 534         ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_LVDS);
 535         if (ret)
 536                 goto err_connector_cleanup;
 537
 538         gma_connector_attach_encoder(gma_connector, gma_encoder);
 539         gma_encoder->type = INTEL_OUTPUT_LVDS;
 540
 541         drm_encoder_helper_add(encoder, &cdv_intel_lvds_helper_funcs);
 542         drm_connector_helper_add(connector,
 543                                  &cdv_intel_lvds_connector_helper_funcs);
 544         connector->display_info.subpixel_order = SubPixelHorizontalRGB;
 545         connector->interlace_allowed = false;
 546         connector->doublescan_allowed = false;
 547
 548         /*Attach connector properties*/
 549         drm_object_attach_property(&connector->base,
 550                                       dev->mode_config.scaling_mode_property,
 551                                       DRM_MODE_SCALE_FULLSCREEN);
 552         drm_object_attach_property(&connector->base,
 553                                       dev_priv->backlight_property,
 554                                       BRIGHTNESS_MAX_LEVEL);
 555
 556         /**
 557          * Set up I2C bus
 558          * FIXME: distroy i2c_bus when exit
 559          */
 560         gma_encoder->i2c_bus = gma_i2c_create(dev, GPIOB, "LVDSBLC_B");
 561         if (!gma_encoder->i2c_bus) {
 562                 dev_printk(KERN_ERR,
 563                         dev->dev, "I2C bus registration failed.\n");
 564                 goto err_encoder_cleanup;
 565         }
 566         gma_encoder->i2c_bus->slave_addr = 0x2C;
 567         dev_priv->lvds_i2c_bus = gma_encoder->i2c_bus;
 568
 569         /*
 570          * LVDS discovery:
 571          * 1) check for EDID on DDC
 572          * 2) check for VBT data
 573          * 3) check to see if LVDS is already on
 574          *    if none of the above, no panel
 575          * 4) make sure lid is open
 576          *    if closed, act like it's not there for now
 577          */
 578
 579         /*
 580          * Attempt to get the fixed panel mode from DDC.  Assume that the
 581          * preferred mode is the right one.
 582          */
 583         mutex_lock(&dev->mode_config.mutex);
 584         psb_intel_ddc_get_modes(connector, &ddc_bus->base);
 585
 586         list_for_each_entry(scan, &connector->probed_modes, head) {
 587                 if (scan->type & DRM_MODE_TYPE_PREFERRED) {
 588                         mode_dev->panel_fixed_mode =
 589                             drm_mode_duplicate(dev, scan);
 590                         goto out;       /* FIXME: check for quirks */
 591                 }
 592         }
 593
 594         /* Failed to get EDID, what about VBT? do we need this?*/
 595         if (dev_priv->lfp_lvds_vbt_mode) {
 596                 mode_dev->panel_fixed_mode =
 597                         drm_mode_duplicate(dev, dev_priv->lfp_lvds_vbt_mode);
 598                 if (mode_dev->panel_fixed_mode) {
 599                         mode_dev->panel_fixed_mode->type |=
 600                                 DRM_MODE_TYPE_PREFERRED;
 601                         goto out;       /* FIXME: check for quirks */
 602                 }
 603         }
 604         /*
 605          * If we didn't get EDID, try checking if the panel is already turned
 606          * on.  If so, assume that whatever is currently programmed is the
 607          * correct mode.
 608          */
 609         lvds = REG_READ(LVDS);
 610         pipe = (lvds & LVDS_PIPEB_SELECT) ? 1 : 0;
 611         crtc = psb_intel_get_crtc_from_pipe(dev, pipe);
 612
 613         if (crtc && (lvds & LVDS_PORT_EN)) {
 614                 mode_dev->panel_fixed_mode =
 615                     cdv_intel_crtc_mode_get(dev, crtc);
 616                 if (mode_dev->panel_fixed_mode) {
 617                         mode_dev->panel_fixed_mode->type |=
 618                             DRM_MODE_TYPE_PREFERRED;
 619                         goto out;       /* FIXME: check for quirks */
 620                 }
 621         }
 622
 623         /* If we still don't have a mode after all that, give up. */
 624         if (!mode_dev->panel_fixed_mode) {
 625                 DRM_DEBUG
 626                         ("Found no modes on the lvds, ignoring the LVDS\n");
 627                 goto err_unlock;
 628         }
 629
 630         /* setup PWM */
 631         {
 632                 u32 pwm;
 633
 634                 pwm = REG_READ(BLC_PWM_CTL2);
 635                 if (pipe == 1)
 636                         pwm |= PWM_PIPE_B;
 637                 else
 638                         pwm &= ~PWM_PIPE_B;
 639                 pwm |= PWM_ENABLE;
 640                 REG_WRITE(BLC_PWM_CTL2, pwm);
 641         }
 642
 643 out:
 644         mutex_unlock(&dev->mode_config.mutex);
 645         return;
 646
 647 err_unlock:
 648         mutex_unlock(&dev->mode_config.mutex);
 649         gma_i2c_destroy(gma_encoder->i2c_bus);
 650 err_encoder_cleanup:
 651         drm_encoder_cleanup(encoder);
 652 err_connector_cleanup:
 653         drm_connector_cleanup(connector);
 654 err_destroy_ddc:
 655         gma_i2c_destroy(ddc_bus);
 656 err_free_lvds_priv:
 657         kfree(lvds_priv);
 658 err_free_connector:
 659         kfree(gma_connector);
 660 err_free_encoder:
 661         kfree(gma_encoder);
 662 }