Pileus Git - ~andy/linux/blob - drivers/gpu/drm/i915/intel_panel.c

   1 /*
   2  * Copyright © 2006-2010 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  *      Chris Wilson <chris@chris-wilson.co.uk>
  29  */
  30
  31 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  32
  33 #include <linux/moduleparam.h>
  34 #include "intel_drv.h"
  35
  36 #define PCI_LBPC 0xf4 /* legacy/combination backlight modes */
  37
  38 void
  39 intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode,
  40                        struct drm_display_mode *adjusted_mode)
  41 {
  42         drm_mode_copy(adjusted_mode, fixed_mode);
  43
  44         drm_mode_set_crtcinfo(adjusted_mode, 0);
  45 }
  46
  47 /* adjusted_mode has been preset to be the panel's fixed mode */
  48 void
  49 intel_pch_panel_fitting(struct intel_crtc *intel_crtc,
  50                         struct intel_crtc_config *pipe_config,
  51                         int fitting_mode)
  52 {
  53         struct drm_display_mode *adjusted_mode;
  54         int x, y, width, height;
  55
  56         adjusted_mode = &pipe_config->adjusted_mode;
  57
  58         x = y = width = height = 0;
  59
  60         /* Native modes don't need fitting */
  61         if (adjusted_mode->hdisplay == pipe_config->pipe_src_w &&
  62             adjusted_mode->vdisplay == pipe_config->pipe_src_h)
  63                 goto done;
  64
  65         switch (fitting_mode) {
  66         case DRM_MODE_SCALE_CENTER:
  67                 width = pipe_config->pipe_src_w;
  68                 height = pipe_config->pipe_src_h;
  69                 x = (adjusted_mode->hdisplay - width + 1)/2;
  70                 y = (adjusted_mode->vdisplay - height + 1)/2;
  71                 break;
  72
  73         case DRM_MODE_SCALE_ASPECT:
  74                 /* Scale but preserve the aspect ratio */
  75                 {
  76                         u32 scaled_width = adjusted_mode->hdisplay
  77                                 * pipe_config->pipe_src_h;
  78                         u32 scaled_height = pipe_config->pipe_src_w
  79                                 * adjusted_mode->vdisplay;
  80                         if (scaled_width > scaled_height) { /* pillar */
  81                                 width = scaled_height / pipe_config->pipe_src_h;
  82                                 if (width & 1)
  83                                         width++;
  84                                 x = (adjusted_mode->hdisplay - width + 1) / 2;
  85                                 y = 0;
  86                                 height = adjusted_mode->vdisplay;
  87                         } else if (scaled_width < scaled_height) { /* letter */
  88                                 height = scaled_width / pipe_config->pipe_src_w;
  89                                 if (height & 1)
  90                                     height++;
  91                                 y = (adjusted_mode->vdisplay - height + 1) / 2;
  92                                 x = 0;
  93                                 width = adjusted_mode->hdisplay;
  94                         } else {
  95                                 x = y = 0;
  96                                 width = adjusted_mode->hdisplay;
  97                                 height = adjusted_mode->vdisplay;
  98                         }
  99                 }
 100                 break;
 101
 102         case DRM_MODE_SCALE_FULLSCREEN:
 103                 x = y = 0;
 104                 width = adjusted_mode->hdisplay;
 105                 height = adjusted_mode->vdisplay;
 106                 break;
 107
 108         default:
 109                 WARN(1, "bad panel fit mode: %d\n", fitting_mode);
 110                 return;
 111         }
 112
 113 done:
 114         pipe_config->pch_pfit.pos = (x << 16) | y;
 115         pipe_config->pch_pfit.size = (width << 16) | height;
 116         pipe_config->pch_pfit.enabled = pipe_config->pch_pfit.size != 0;
 117 }
 118
 119 static void
 120 centre_horizontally(struct drm_display_mode *mode,
 121                     int width)
 122 {
 123         u32 border, sync_pos, blank_width, sync_width;
 124
 125         /* keep the hsync and hblank widths constant */
 126         sync_width = mode->crtc_hsync_end - mode->crtc_hsync_start;
 127         blank_width = mode->crtc_hblank_end - mode->crtc_hblank_start;
 128         sync_pos = (blank_width - sync_width + 1) / 2;
 129
 130         border = (mode->hdisplay - width + 1) / 2;
 131         border += border & 1; /* make the border even */
 132
 133         mode->crtc_hdisplay = width;
 134         mode->crtc_hblank_start = width + border;
 135         mode->crtc_hblank_end = mode->crtc_hblank_start + blank_width;
 136
 137         mode->crtc_hsync_start = mode->crtc_hblank_start + sync_pos;
 138         mode->crtc_hsync_end = mode->crtc_hsync_start + sync_width;
 139 }
 140
 141 static void
 142 centre_vertically(struct drm_display_mode *mode,
 143                   int height)
 144 {
 145         u32 border, sync_pos, blank_width, sync_width;
 146
 147         /* keep the vsync and vblank widths constant */
 148         sync_width = mode->crtc_vsync_end - mode->crtc_vsync_start;
 149         blank_width = mode->crtc_vblank_end - mode->crtc_vblank_start;
 150         sync_pos = (blank_width - sync_width + 1) / 2;
 151
 152         border = (mode->vdisplay - height + 1) / 2;
 153
 154         mode->crtc_vdisplay = height;
 155         mode->crtc_vblank_start = height + border;
 156         mode->crtc_vblank_end = mode->crtc_vblank_start + blank_width;
 157
 158         mode->crtc_vsync_start = mode->crtc_vblank_start + sync_pos;
 159         mode->crtc_vsync_end = mode->crtc_vsync_start + sync_width;
 160 }
 161
 162 static inline u32 panel_fitter_scaling(u32 source, u32 target)
 163 {
 164         /*
 165          * Floating point operation is not supported. So the FACTOR
 166          * is defined, which can avoid the floating point computation
 167          * when calculating the panel ratio.
 168          */
 169 #define ACCURACY 12
 170 #define FACTOR (1 << ACCURACY)
 171         u32 ratio = source * FACTOR / target;
 172         return (FACTOR * ratio + FACTOR/2) / FACTOR;
 173 }
 174
 175 static void i965_scale_aspect(struct intel_crtc_config *pipe_config,
 176                               u32 *pfit_control)
 177 {
 178         struct drm_display_mode *adjusted_mode = &pipe_config->adjusted_mode;
 179         u32 scaled_width = adjusted_mode->hdisplay *
 180                 pipe_config->pipe_src_h;
 181         u32 scaled_height = pipe_config->pipe_src_w *
 182                 adjusted_mode->vdisplay;
 183
 184         /* 965+ is easy, it does everything in hw */
 185         if (scaled_width > scaled_height)
 186                 *pfit_control |= PFIT_ENABLE |
 187                         PFIT_SCALING_PILLAR;
 188         else if (scaled_width < scaled_height)
 189                 *pfit_control |= PFIT_ENABLE |
 190                         PFIT_SCALING_LETTER;
 191         else if (adjusted_mode->hdisplay != pipe_config->pipe_src_w)
 192                 *pfit_control |= PFIT_ENABLE | PFIT_SCALING_AUTO;
 193 }
 194
 195 static void i9xx_scale_aspect(struct intel_crtc_config *pipe_config,
 196                               u32 *pfit_control, u32 *pfit_pgm_ratios,
 197                               u32 *border)
 198 {
 199         struct drm_display_mode *adjusted_mode = &pipe_config->adjusted_mode;
 200         u32 scaled_width = adjusted_mode->hdisplay *
 201                 pipe_config->pipe_src_h;
 202         u32 scaled_height = pipe_config->pipe_src_w *
 203                 adjusted_mode->vdisplay;
 204         u32 bits;
 205
 206         /*
 207          * For earlier chips we have to calculate the scaling
 208          * ratio by hand and program it into the
 209          * PFIT_PGM_RATIO register
 210          */
 211         if (scaled_width > scaled_height) { /* pillar */
 212                 centre_horizontally(adjusted_mode,
 213                                     scaled_height /
 214                                     pipe_config->pipe_src_h);
 215
 216                 *border = LVDS_BORDER_ENABLE;
 217                 if (pipe_config->pipe_src_h != adjusted_mode->vdisplay) {
 218                         bits = panel_fitter_scaling(pipe_config->pipe_src_h,
 219                                                     adjusted_mode->vdisplay);
 220
 221                         *pfit_pgm_ratios |= (bits << PFIT_HORIZ_SCALE_SHIFT |
 222                                              bits << PFIT_VERT_SCALE_SHIFT);
 223                         *pfit_control |= (PFIT_ENABLE |
 224                                           VERT_INTERP_BILINEAR |
 225                                           HORIZ_INTERP_BILINEAR);
 226                 }
 227         } else if (scaled_width < scaled_height) { /* letter */
 228                 centre_vertically(adjusted_mode,
 229                                   scaled_width /
 230                                   pipe_config->pipe_src_w);
 231
 232                 *border = LVDS_BORDER_ENABLE;
 233                 if (pipe_config->pipe_src_w != adjusted_mode->hdisplay) {
 234                         bits = panel_fitter_scaling(pipe_config->pipe_src_w,
 235                                                     adjusted_mode->hdisplay);
 236
 237                         *pfit_pgm_ratios |= (bits << PFIT_HORIZ_SCALE_SHIFT |
 238                                              bits << PFIT_VERT_SCALE_SHIFT);
 239                         *pfit_control |= (PFIT_ENABLE |
 240                                           VERT_INTERP_BILINEAR |
 241                                           HORIZ_INTERP_BILINEAR);
 242                 }
 243         } else {
 244                 /* Aspects match, Let hw scale both directions */
 245                 *pfit_control |= (PFIT_ENABLE |
 246                                   VERT_AUTO_SCALE | HORIZ_AUTO_SCALE |
 247                                   VERT_INTERP_BILINEAR |
 248                                   HORIZ_INTERP_BILINEAR);
 249         }
 250 }
 251
 252 void intel_gmch_panel_fitting(struct intel_crtc *intel_crtc,
 253                               struct intel_crtc_config *pipe_config,
 254                               int fitting_mode)
 255 {
 256         struct drm_device *dev = intel_crtc->base.dev;
 257         u32 pfit_control = 0, pfit_pgm_ratios = 0, border = 0;
 258         struct drm_display_mode *adjusted_mode;
 259
 260         adjusted_mode = &pipe_config->adjusted_mode;
 261
 262         /* Native modes don't need fitting */
 263         if (adjusted_mode->hdisplay == pipe_config->pipe_src_w &&
 264             adjusted_mode->vdisplay == pipe_config->pipe_src_h)
 265                 goto out;
 266
 267         switch (fitting_mode) {
 268         case DRM_MODE_SCALE_CENTER:
 269                 /*
 270                  * For centered modes, we have to calculate border widths &
 271                  * heights and modify the values programmed into the CRTC.
 272                  */
 273                 centre_horizontally(adjusted_mode, pipe_config->pipe_src_w);
 274                 centre_vertically(adjusted_mode, pipe_config->pipe_src_h);
 275                 border = LVDS_BORDER_ENABLE;
 276                 break;
 277         case DRM_MODE_SCALE_ASPECT:
 278                 /* Scale but preserve the aspect ratio */
 279                 if (INTEL_INFO(dev)->gen >= 4)
 280                         i965_scale_aspect(pipe_config, &pfit_control);
 281                 else
 282                         i9xx_scale_aspect(pipe_config, &pfit_control,
 283                                           &pfit_pgm_ratios, &border);
 284                 break;
 285         case DRM_MODE_SCALE_FULLSCREEN:
 286                 /*
 287                  * Full scaling, even if it changes the aspect ratio.
 288                  * Fortunately this is all done for us in hw.
 289                  */
 290                 if (pipe_config->pipe_src_h != adjusted_mode->vdisplay ||
 291                     pipe_config->pipe_src_w != adjusted_mode->hdisplay) {
 292                         pfit_control |= PFIT_ENABLE;
 293                         if (INTEL_INFO(dev)->gen >= 4)
 294                                 pfit_control |= PFIT_SCALING_AUTO;
 295                         else
 296                                 pfit_control |= (VERT_AUTO_SCALE |
 297                                                  VERT_INTERP_BILINEAR |
 298                                                  HORIZ_AUTO_SCALE |
 299                                                  HORIZ_INTERP_BILINEAR);
 300                 }
 301                 break;
 302         default:
 303                 WARN(1, "bad panel fit mode: %d\n", fitting_mode);
 304                 return;
 305         }
 306
 307         /* 965+ wants fuzzy fitting */
 308         /* FIXME: handle multiple panels by failing gracefully */
 309         if (INTEL_INFO(dev)->gen >= 4)
 310                 pfit_control |= ((intel_crtc->pipe << PFIT_PIPE_SHIFT) |
 311                                  PFIT_FILTER_FUZZY);
 312
 313 out:
 314         if ((pfit_control & PFIT_ENABLE) == 0) {
 315                 pfit_control = 0;
 316                 pfit_pgm_ratios = 0;
 317         }
 318
 319         /* Make sure pre-965 set dither correctly for 18bpp panels. */
 320         if (INTEL_INFO(dev)->gen < 4 && pipe_config->pipe_bpp == 18)
 321                 pfit_control |= PANEL_8TO6_DITHER_ENABLE;
 322
 323         pipe_config->gmch_pfit.control = pfit_control;
 324         pipe_config->gmch_pfit.pgm_ratios = pfit_pgm_ratios;
 325         pipe_config->gmch_pfit.lvds_border_bits = border;
 326 }
 327
 328 static int i915_panel_invert_brightness;
 329 MODULE_PARM_DESC(invert_brightness, "Invert backlight brightness "
 330         "(-1 force normal, 0 machine defaults, 1 force inversion), please "
 331         "report PCI device ID, subsystem vendor and subsystem device ID "
 332         "to dri-devel@lists.freedesktop.org, if your machine needs it. "
 333         "It will then be included in an upcoming module version.");
 334 module_param_named(invert_brightness, i915_panel_invert_brightness, int, 0600);
 335 static u32 intel_panel_compute_brightness(struct intel_connector *connector,
 336                                           u32 val)
 337 {
 338         struct drm_device *dev = connector->base.dev;
 339         struct drm_i915_private *dev_priv = dev->dev_private;
 340         struct intel_panel *panel = &connector->panel;
 341
 342         WARN_ON(panel->backlight.max == 0);
 343
 344         if (i915_panel_invert_brightness < 0)
 345                 return val;
 346
 347         if (i915_panel_invert_brightness > 0 ||
 348             dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
 349                 return panel->backlight.max - val;
 350         }
 351
 352         return val;
 353 }
 354
 355 static u32 bdw_get_backlight(struct intel_connector *connector)
 356 {
 357         struct drm_device *dev = connector->base.dev;
 358         struct drm_i915_private *dev_priv = dev->dev_private;
 359
 360         return I915_READ(BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
 361 }
 362
 363 static u32 pch_get_backlight(struct intel_connector *connector)
 364 {
 365         struct drm_device *dev = connector->base.dev;
 366         struct drm_i915_private *dev_priv = dev->dev_private;
 367
 368         return I915_READ(BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
 369 }
 370
 371 static u32 i9xx_get_backlight(struct intel_connector *connector)
 372 {
 373         struct drm_device *dev = connector->base.dev;
 374         struct drm_i915_private *dev_priv = dev->dev_private;
 375         struct intel_panel *panel = &connector->panel;
 376         u32 val;
 377
 378         val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
 379         if (INTEL_INFO(dev)->gen < 4)
 380                 val >>= 1;
 381
 382         if (panel->backlight.combination_mode) {
 383                 u8 lbpc;
 384
 385                 pci_read_config_byte(dev->pdev, PCI_LBPC, &lbpc);
 386                 val *= lbpc;
 387         }
 388
 389         return val;
 390 }
 391
 392 static u32 _vlv_get_backlight(struct drm_device *dev, enum pipe pipe)
 393 {
 394         struct drm_i915_private *dev_priv = dev->dev_private;
 395
 396         return I915_READ(VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
 397 }
 398
 399 static u32 vlv_get_backlight(struct intel_connector *connector)
 400 {
 401         struct drm_device *dev = connector->base.dev;
 402         enum pipe pipe = intel_get_pipe_from_connector(connector);
 403
 404         return _vlv_get_backlight(dev, pipe);
 405 }
 406
 407 static u32 intel_panel_get_backlight(struct intel_connector *connector)
 408 {
 409         struct drm_device *dev = connector->base.dev;
 410         struct drm_i915_private *dev_priv = dev->dev_private;
 411         u32 val;
 412         unsigned long flags;
 413
 414         spin_lock_irqsave(&dev_priv->backlight_lock, flags);
 415
 416         val = dev_priv->display.get_backlight(connector);
 417         val = intel_panel_compute_brightness(connector, val);
 418
 419         spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
 420
 421         DRM_DEBUG_DRIVER("get backlight PWM = %d\n", val);
 422         return val;
 423 }
 424
 425 static void bdw_set_backlight(struct intel_connector *connector, u32 level)
 426 {
 427         struct drm_device *dev = connector->base.dev;
 428         struct drm_i915_private *dev_priv = dev->dev_private;
 429         u32 val = I915_READ(BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 430         I915_WRITE(BLC_PWM_PCH_CTL2, val | level);
 431 }
 432
 433 static void pch_set_backlight(struct intel_connector *connector, u32 level)
 434 {
 435         struct drm_device *dev = connector->base.dev;
 436         struct drm_i915_private *dev_priv = dev->dev_private;
 437         u32 tmp;
 438
 439         tmp = I915_READ(BLC_PWM_CPU_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 440         I915_WRITE(BLC_PWM_CPU_CTL, tmp | level);
 441 }
 442
 443 static void i9xx_set_backlight(struct intel_connector *connector, u32 level)
 444 {
 445         struct drm_device *dev = connector->base.dev;
 446         struct drm_i915_private *dev_priv = dev->dev_private;
 447         struct intel_panel *panel = &connector->panel;
 448         u32 tmp, mask;
 449
 450         WARN_ON(panel->backlight.max == 0);
 451
 452         if (panel->backlight.combination_mode) {
 453                 u8 lbpc;
 454
 455                 lbpc = level * 0xfe / panel->backlight.max + 1;
 456                 level /= lbpc;
 457                 pci_write_config_byte(dev->pdev, PCI_LBPC, lbpc);
 458         }
 459
 460         if (IS_GEN4(dev)) {
 461                 mask = BACKLIGHT_DUTY_CYCLE_MASK;
 462         } else {
 463                 level <<= 1;
 464                 mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV;
 465         }
 466
 467         tmp = I915_READ(BLC_PWM_CTL) & ~mask;
 468         I915_WRITE(BLC_PWM_CTL, tmp | level);
 469 }
 470
 471 static void vlv_set_backlight(struct intel_connector *connector, u32 level)
 472 {
 473         struct drm_device *dev = connector->base.dev;
 474         struct drm_i915_private *dev_priv = dev->dev_private;
 475         enum pipe pipe = intel_get_pipe_from_connector(connector);
 476         u32 tmp;
 477
 478         tmp = I915_READ(VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 479         I915_WRITE(VLV_BLC_PWM_CTL(pipe), tmp | level);
 480 }
 481
 482 static void
 483 intel_panel_actually_set_backlight(struct intel_connector *connector, u32 level)
 484 {
 485         struct drm_device *dev = connector->base.dev;
 486         struct drm_i915_private *dev_priv = dev->dev_private;
 487
 488         DRM_DEBUG_DRIVER("set backlight PWM = %d\n", level);
 489
 490         level = intel_panel_compute_brightness(connector, level);
 491         dev_priv->display.set_backlight(connector, level);
 492 }
 493
 494 /* set backlight brightness to level in range [0..max] */
 495 void intel_panel_set_backlight(struct intel_connector *connector, u32 level,
 496                                u32 max)
 497 {
 498         struct drm_device *dev = connector->base.dev;
 499         struct drm_i915_private *dev_priv = dev->dev_private;
 500         struct intel_panel *panel = &connector->panel;
 501         enum pipe pipe = intel_get_pipe_from_connector(connector);
 502         u32 freq;
 503         unsigned long flags;
 504
 505         if (!panel->backlight.present || pipe == INVALID_PIPE)
 506                 return;
 507
 508         spin_lock_irqsave(&dev_priv->backlight_lock, flags);
 509
 510         WARN_ON(panel->backlight.max == 0);
 511
 512         /* scale to hardware max, but be careful to not overflow */
 513         freq = panel->backlight.max;
 514         if (freq < max)
 515                 level = level * freq / max;
 516         else
 517                 level = freq / max * level;
 518
 519         panel->backlight.level = level;
 520         if (panel->backlight.device)
 521                 panel->backlight.device->props.brightness = level;
 522
 523         if (panel->backlight.enabled)
 524                 intel_panel_actually_set_backlight(connector, level);
 525
 526         spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
 527 }
 528
 529 static void pch_disable_backlight(struct intel_connector *connector)
 530 {
 531         struct drm_device *dev = connector->base.dev;
 532         struct drm_i915_private *dev_priv = dev->dev_private;
 533         u32 tmp;
 534
 535         intel_panel_actually_set_backlight(connector, 0);
 536
 537         tmp = I915_READ(BLC_PWM_CPU_CTL2);
 538         I915_WRITE(BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
 539
 540         tmp = I915_READ(BLC_PWM_PCH_CTL1);
 541         I915_WRITE(BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
 542 }
 543
 544 static void i9xx_disable_backlight(struct intel_connector *connector)
 545 {
 546         intel_panel_actually_set_backlight(connector, 0);
 547 }
 548
 549 static void i965_disable_backlight(struct intel_connector *connector)
 550 {
 551         struct drm_device *dev = connector->base.dev;
 552         struct drm_i915_private *dev_priv = dev->dev_private;
 553         u32 tmp;
 554
 555         intel_panel_actually_set_backlight(connector, 0);
 556
 557         tmp = I915_READ(BLC_PWM_CTL2);
 558         I915_WRITE(BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
 559 }
 560
 561 static void vlv_disable_backlight(struct intel_connector *connector)
 562 {
 563         struct drm_device *dev = connector->base.dev;
 564         struct drm_i915_private *dev_priv = dev->dev_private;
 565         enum pipe pipe = intel_get_pipe_from_connector(connector);
 566         u32 tmp;
 567
 568         intel_panel_actually_set_backlight(connector, 0);
 569
 570         tmp = I915_READ(VLV_BLC_PWM_CTL2(pipe));
 571         I915_WRITE(VLV_BLC_PWM_CTL2(pipe), tmp & ~BLM_PWM_ENABLE);
 572 }
 573
 574 void intel_panel_disable_backlight(struct intel_connector *connector)
 575 {
 576         struct drm_device *dev = connector->base.dev;
 577         struct drm_i915_private *dev_priv = dev->dev_private;
 578         struct intel_panel *panel = &connector->panel;
 579         enum pipe pipe = intel_get_pipe_from_connector(connector);
 580         unsigned long flags;
 581
 582         if (!panel->backlight.present || pipe == INVALID_PIPE)
 583                 return;
 584
 585         /*
 586          * Do not disable backlight on the vgaswitcheroo path. When switching
 587          * away from i915, the other client may depend on i915 to handle the
 588          * backlight. This will leave the backlight on unnecessarily when
 589          * another client is not activated.
 590          */
 591         if (dev->switch_power_state == DRM_SWITCH_POWER_CHANGING) {
 592                 DRM_DEBUG_DRIVER("Skipping backlight disable on vga switch\n");
 593                 return;
 594         }
 595
 596         spin_lock_irqsave(&dev_priv->backlight_lock, flags);
 597
 598         panel->backlight.enabled = false;
 599         dev_priv->display.disable_backlight(connector);
 600
 601         spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
 602 }
 603
 604 static void bdw_enable_backlight(struct intel_connector *connector)
 605 {
 606         struct drm_device *dev = connector->base.dev;
 607         struct drm_i915_private *dev_priv = dev->dev_private;
 608         struct intel_panel *panel = &connector->panel;
 609         u32 pch_ctl1, pch_ctl2;
 610
 611         pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
 612         if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
 613                 DRM_DEBUG_KMS("pch backlight already enabled\n");
 614                 pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
 615                 I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
 616         }
 617
 618         pch_ctl2 = panel->backlight.max << 16;
 619         I915_WRITE(BLC_PWM_PCH_CTL2, pch_ctl2);
 620
 621         pch_ctl1 = 0;
 622         if (panel->backlight.active_low_pwm)
 623                 pch_ctl1 |= BLM_PCH_POLARITY;
 624
 625         /* BDW always uses the pch pwm controls. */
 626         pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
 627
 628         I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
 629         POSTING_READ(BLC_PWM_PCH_CTL1);
 630         I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
 631
 632         /* This won't stick until the above enable. */
 633         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 634 }
 635
 636 static void pch_enable_backlight(struct intel_connector *connector)
 637 {
 638         struct drm_device *dev = connector->base.dev;
 639         struct drm_i915_private *dev_priv = dev->dev_private;
 640         struct intel_panel *panel = &connector->panel;
 641         enum pipe pipe = intel_get_pipe_from_connector(connector);
 642         enum transcoder cpu_transcoder =
 643                 intel_pipe_to_cpu_transcoder(dev_priv, pipe);
 644         u32 cpu_ctl2, pch_ctl1, pch_ctl2;
 645
 646         cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
 647         if (cpu_ctl2 & BLM_PWM_ENABLE) {
 648                 WARN(1, "cpu backlight already enabled\n");
 649                 cpu_ctl2 &= ~BLM_PWM_ENABLE;
 650                 I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2);
 651         }
 652
 653         pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
 654         if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
 655                 DRM_DEBUG_KMS("pch backlight already enabled\n");
 656                 pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
 657                 I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
 658         }
 659
 660         if (cpu_transcoder == TRANSCODER_EDP)
 661                 cpu_ctl2 = BLM_TRANSCODER_EDP;
 662         else
 663                 cpu_ctl2 = BLM_PIPE(cpu_transcoder);
 664         I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2);
 665         POSTING_READ(BLC_PWM_CPU_CTL2);
 666         I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
 667
 668         /* This won't stick until the above enable. */
 669         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 670
 671         pch_ctl2 = panel->backlight.max << 16;
 672         I915_WRITE(BLC_PWM_PCH_CTL2, pch_ctl2);
 673
 674         pch_ctl1 = 0;
 675         if (panel->backlight.active_low_pwm)
 676                 pch_ctl1 |= BLM_PCH_POLARITY;
 677
 678         I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
 679         POSTING_READ(BLC_PWM_PCH_CTL1);
 680         I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
 681 }
 682
 683 static void i9xx_enable_backlight(struct intel_connector *connector)
 684 {
 685         struct drm_device *dev = connector->base.dev;
 686         struct drm_i915_private *dev_priv = dev->dev_private;
 687         struct intel_panel *panel = &connector->panel;
 688         u32 ctl, freq;
 689
 690         ctl = I915_READ(BLC_PWM_CTL);
 691         if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
 692                 WARN(1, "backlight already enabled\n");
 693                 I915_WRITE(BLC_PWM_CTL, 0);
 694         }
 695
 696         freq = panel->backlight.max;
 697         if (panel->backlight.combination_mode)
 698                 freq /= 0xff;
 699
 700         ctl = freq << 17;
 701         if (panel->backlight.combination_mode)
 702                 ctl |= BLM_LEGACY_MODE;
 703         if (IS_PINEVIEW(dev) && panel->backlight.active_low_pwm)
 704                 ctl |= BLM_POLARITY_PNV;
 705
 706         I915_WRITE(BLC_PWM_CTL, ctl);
 707         POSTING_READ(BLC_PWM_CTL);
 708
 709         /* XXX: combine this into above write? */
 710         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 711 }
 712
 713 static void i965_enable_backlight(struct intel_connector *connector)
 714 {
 715         struct drm_device *dev = connector->base.dev;
 716         struct drm_i915_private *dev_priv = dev->dev_private;
 717         struct intel_panel *panel = &connector->panel;
 718         enum pipe pipe = intel_get_pipe_from_connector(connector);
 719         u32 ctl, ctl2, freq;
 720
 721         ctl2 = I915_READ(BLC_PWM_CTL2);
 722         if (ctl2 & BLM_PWM_ENABLE) {
 723                 WARN(1, "backlight already enabled\n");
 724                 ctl2 &= ~BLM_PWM_ENABLE;
 725                 I915_WRITE(BLC_PWM_CTL2, ctl2);
 726         }
 727
 728         freq = panel->backlight.max;
 729         if (panel->backlight.combination_mode)
 730                 freq /= 0xff;
 731
 732         ctl = freq << 16;
 733         I915_WRITE(BLC_PWM_CTL, ctl);
 734
 735         /* XXX: combine this into above write? */
 736         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 737
 738         ctl2 = BLM_PIPE(pipe);
 739         if (panel->backlight.combination_mode)
 740                 ctl2 |= BLM_COMBINATION_MODE;
 741         if (panel->backlight.active_low_pwm)
 742                 ctl2 |= BLM_POLARITY_I965;
 743         I915_WRITE(BLC_PWM_CTL2, ctl2);
 744         POSTING_READ(BLC_PWM_CTL2);
 745         I915_WRITE(BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
 746 }
 747
 748 static void vlv_enable_backlight(struct intel_connector *connector)
 749 {
 750         struct drm_device *dev = connector->base.dev;
 751         struct drm_i915_private *dev_priv = dev->dev_private;
 752         struct intel_panel *panel = &connector->panel;
 753         enum pipe pipe = intel_get_pipe_from_connector(connector);
 754         u32 ctl, ctl2;
 755
 756         ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
 757         if (ctl2 & BLM_PWM_ENABLE) {
 758                 WARN(1, "backlight already enabled\n");
 759                 ctl2 &= ~BLM_PWM_ENABLE;
 760                 I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
 761         }
 762
 763         ctl = panel->backlight.max << 16;
 764         I915_WRITE(VLV_BLC_PWM_CTL(pipe), ctl);
 765
 766         /* XXX: combine this into above write? */
 767         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 768
 769         ctl2 = 0;
 770         if (panel->backlight.active_low_pwm)
 771                 ctl2 |= BLM_POLARITY_I965;
 772         I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
 773         POSTING_READ(VLV_BLC_PWM_CTL2(pipe));
 774         I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2 | BLM_PWM_ENABLE);
 775 }
 776
 777 void intel_panel_enable_backlight(struct intel_connector *connector)
 778 {
 779         struct drm_device *dev = connector->base.dev;
 780         struct drm_i915_private *dev_priv = dev->dev_private;
 781         struct intel_panel *panel = &connector->panel;
 782         enum pipe pipe = intel_get_pipe_from_connector(connector);
 783         unsigned long flags;
 784
 785         if (!panel->backlight.present || pipe == INVALID_PIPE)
 786                 return;
 787
 788         DRM_DEBUG_KMS("pipe %c\n", pipe_name(pipe));
 789
 790         spin_lock_irqsave(&dev_priv->backlight_lock, flags);
 791
 792         WARN_ON(panel->backlight.max == 0);
 793
 794         if (panel->backlight.level == 0) {
 795                 panel->backlight.level = panel->backlight.max;
 796                 if (panel->backlight.device)
 797                         panel->backlight.device->props.brightness =
 798                                 panel->backlight.level;
 799         }
 800
 801         dev_priv->display.enable_backlight(connector);
 802         panel->backlight.enabled = true;
 803
 804         spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
 805 }
 806
 807 enum drm_connector_status
 808 intel_panel_detect(struct drm_device *dev)
 809 {
 810         struct drm_i915_private *dev_priv = dev->dev_private;
 811
 812         /* Assume that the BIOS does not lie through the OpRegion... */
 813         if (!i915_panel_ignore_lid && dev_priv->opregion.lid_state) {
 814                 return ioread32(dev_priv->opregion.lid_state) & 0x1 ?
 815                         connector_status_connected :
 816                         connector_status_disconnected;
 817         }
 818
 819         switch (i915_panel_ignore_lid) {
 820         case -2:
 821                 return connector_status_connected;
 822         case -1:
 823                 return connector_status_disconnected;
 824         default:
 825                 return connector_status_unknown;
 826         }
 827 }
 828
 829 #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
 830 static int intel_backlight_device_update_status(struct backlight_device *bd)
 831 {
 832         struct intel_connector *connector = bl_get_data(bd);
 833         struct drm_device *dev = connector->base.dev;
 834
 835         mutex_lock(&dev->mode_config.mutex);
 836         DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
 837                       bd->props.brightness, bd->props.max_brightness);
 838         intel_panel_set_backlight(connector, bd->props.brightness,
 839                                   bd->props.max_brightness);
 840         mutex_unlock(&dev->mode_config.mutex);
 841         return 0;
 842 }
 843
 844 static int intel_backlight_device_get_brightness(struct backlight_device *bd)
 845 {
 846         struct intel_connector *connector = bl_get_data(bd);
 847         struct drm_device *dev = connector->base.dev;
 848         struct drm_i915_private *dev_priv = dev->dev_private;
 849         int ret;
 850
 851         intel_runtime_pm_get(dev_priv);
 852         mutex_lock(&dev->mode_config.mutex);
 853         ret = intel_panel_get_backlight(connector);
 854         mutex_unlock(&dev->mode_config.mutex);
 855         intel_runtime_pm_put(dev_priv);
 856
 857         return ret;
 858 }
 859
 860 static const struct backlight_ops intel_backlight_device_ops = {
 861         .update_status = intel_backlight_device_update_status,
 862         .get_brightness = intel_backlight_device_get_brightness,
 863 };
 864
 865 static int intel_backlight_device_register(struct intel_connector *connector)
 866 {
 867         struct intel_panel *panel = &connector->panel;
 868         struct backlight_properties props;
 869
 870         if (WARN_ON(panel->backlight.device))
 871                 return -ENODEV;
 872
 873         BUG_ON(panel->backlight.max == 0);
 874
 875         memset(&props, 0, sizeof(props));
 876         props.type = BACKLIGHT_RAW;
 877         props.brightness = panel->backlight.level;
 878         props.max_brightness = panel->backlight.max;
 879
 880         /*
 881          * Note: using the same name independent of the connector prevents
 882          * registration of multiple backlight devices in the driver.
 883          */
 884         panel->backlight.device =
 885                 backlight_device_register("intel_backlight",
 886                                           connector->base.kdev,
 887                                           connector,
 888                                           &intel_backlight_device_ops, &props);
 889
 890         if (IS_ERR(panel->backlight.device)) {
 891                 DRM_ERROR("Failed to register backlight: %ld\n",
 892                           PTR_ERR(panel->backlight.device));
 893                 panel->backlight.device = NULL;
 894                 return -ENODEV;
 895         }
 896         return 0;
 897 }
 898
 899 static void intel_backlight_device_unregister(struct intel_connector *connector)
 900 {
 901         struct intel_panel *panel = &connector->panel;
 902
 903         if (panel->backlight.device) {
 904                 backlight_device_unregister(panel->backlight.device);
 905                 panel->backlight.device = NULL;
 906         }
 907 }
 908 #else /* CONFIG_BACKLIGHT_CLASS_DEVICE */
 909 static int intel_backlight_device_register(struct intel_connector *connector)
 910 {
 911         return 0;
 912 }
 913 static void intel_backlight_device_unregister(struct intel_connector *connector)
 914 {
 915 }
 916 #endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
 917
 918 /*
 919  * Note: The setup hooks can't assume pipe is set!
 920  *
 921  * XXX: Query mode clock or hardware clock and program PWM modulation frequency
 922  * appropriately when it's 0. Use VBT and/or sane defaults.
 923  */
 924 static int bdw_setup_backlight(struct intel_connector *connector)
 925 {
 926         struct drm_device *dev = connector->base.dev;
 927         struct drm_i915_private *dev_priv = dev->dev_private;
 928         struct intel_panel *panel = &connector->panel;
 929         u32 pch_ctl1, pch_ctl2, val;
 930
 931         pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
 932         panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
 933
 934         pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
 935         panel->backlight.max = pch_ctl2 >> 16;
 936         if (!panel->backlight.max)
 937                 return -ENODEV;
 938
 939         val = bdw_get_backlight(connector);
 940         panel->backlight.level = intel_panel_compute_brightness(connector, val);
 941
 942         panel->backlight.enabled = (pch_ctl1 & BLM_PCH_PWM_ENABLE) &&
 943                 panel->backlight.level != 0;
 944
 945         return 0;
 946 }
 947
 948 static int pch_setup_backlight(struct intel_connector *connector)
 949 {
 950         struct drm_device *dev = connector->base.dev;
 951         struct drm_i915_private *dev_priv = dev->dev_private;
 952         struct intel_panel *panel = &connector->panel;
 953         u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
 954
 955         pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
 956         panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
 957
 958         pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
 959         panel->backlight.max = pch_ctl2 >> 16;
 960         if (!panel->backlight.max)
 961                 return -ENODEV;
 962
 963         val = pch_get_backlight(connector);
 964         panel->backlight.level = intel_panel_compute_brightness(connector, val);
 965
 966         cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
 967         panel->backlight.enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
 968                 (pch_ctl1 & BLM_PCH_PWM_ENABLE) && panel->backlight.level != 0;
 969
 970         return 0;
 971 }
 972
 973 static int i9xx_setup_backlight(struct intel_connector *connector)
 974 {
 975         struct drm_device *dev = connector->base.dev;
 976         struct drm_i915_private *dev_priv = dev->dev_private;
 977         struct intel_panel *panel = &connector->panel;
 978         u32 ctl, val;
 979
 980         ctl = I915_READ(BLC_PWM_CTL);
 981
 982         if (IS_GEN2(dev) || IS_I915GM(dev) || IS_I945GM(dev))
 983                 panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
 984
 985         if (IS_PINEVIEW(dev))
 986                 panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
 987
 988         panel->backlight.max = ctl >> 17;
 989         if (panel->backlight.combination_mode)
 990                 panel->backlight.max *= 0xff;
 991
 992         if (!panel->backlight.max)
 993                 return -ENODEV;
 994
 995         val = i9xx_get_backlight(connector);
 996         panel->backlight.level = intel_panel_compute_brightness(connector, val);
 997
 998         panel->backlight.enabled = panel->backlight.level != 0;
 999
1000         return 0;
1001 }
1002
1003 static int i965_setup_backlight(struct intel_connector *connector)
1004 {
1005         struct drm_device *dev = connector->base.dev;
1006         struct drm_i915_private *dev_priv = dev->dev_private;
1007         struct intel_panel *panel = &connector->panel;
1008         u32 ctl, ctl2, val;
1009
1010         ctl2 = I915_READ(BLC_PWM_CTL2);
1011         panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
1012         panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1013
1014         ctl = I915_READ(BLC_PWM_CTL);
1015         panel->backlight.max = ctl >> 16;
1016         if (panel->backlight.combination_mode)
1017                 panel->backlight.max *= 0xff;
1018
1019         if (!panel->backlight.max)
1020                 return -ENODEV;
1021
1022         val = i9xx_get_backlight(connector);
1023         panel->backlight.level = intel_panel_compute_brightness(connector, val);
1024
1025         panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
1026                 panel->backlight.level != 0;
1027
1028         return 0;
1029 }
1030
1031 static int vlv_setup_backlight(struct intel_connector *connector)
1032 {
1033         struct drm_device *dev = connector->base.dev;
1034         struct drm_i915_private *dev_priv = dev->dev_private;
1035         struct intel_panel *panel = &connector->panel;
1036         enum pipe pipe;
1037         u32 ctl, ctl2, val;
1038
1039         for_each_pipe(pipe) {
1040                 u32 cur_val = I915_READ(VLV_BLC_PWM_CTL(pipe));
1041
1042                 /* Skip if the modulation freq is already set */
1043                 if (cur_val & ~BACKLIGHT_DUTY_CYCLE_MASK)
1044                         continue;
1045
1046                 cur_val &= BACKLIGHT_DUTY_CYCLE_MASK;
1047                 I915_WRITE(VLV_BLC_PWM_CTL(pipe), (0xf42 << 16) |
1048                            cur_val);
1049         }
1050
1051         ctl2 = I915_READ(VLV_BLC_PWM_CTL2(PIPE_A));
1052         panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1053
1054         ctl = I915_READ(VLV_BLC_PWM_CTL(PIPE_A));
1055         panel->backlight.max = ctl >> 16;
1056         if (!panel->backlight.max)
1057                 return -ENODEV;
1058
1059         val = _vlv_get_backlight(dev, PIPE_A);
1060         panel->backlight.level = intel_panel_compute_brightness(connector, val);
1061
1062         panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
1063                 panel->backlight.level != 0;
1064
1065         return 0;
1066 }
1067
1068 int intel_panel_setup_backlight(struct drm_connector *connector)
1069 {
1070         struct drm_device *dev = connector->dev;
1071         struct drm_i915_private *dev_priv = dev->dev_private;
1072         struct intel_connector *intel_connector = to_intel_connector(connector);
1073         struct intel_panel *panel = &intel_connector->panel;
1074         unsigned long flags;
1075         int ret;
1076
1077         /* set level and max in panel struct */
1078         spin_lock_irqsave(&dev_priv->backlight_lock, flags);
1079         ret = dev_priv->display.setup_backlight(intel_connector);
1080         spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
1081
1082         if (ret) {
1083                 DRM_DEBUG_KMS("failed to setup backlight for connector %s\n",
1084                               drm_get_connector_name(connector));
1085                 return ret;
1086         }
1087
1088         intel_backlight_device_register(intel_connector);
1089
1090         panel->backlight.present = true;
1091
1092         DRM_DEBUG_KMS("backlight initialized, %s, brightness %u/%u, "
1093                       "sysfs interface %sregistered\n",
1094                       panel->backlight.enabled ? "enabled" : "disabled",
1095                       panel->backlight.level, panel->backlight.max,
1096                       panel->backlight.device ? "" : "not ");
1097
1098         return 0;
1099 }
1100
1101 void intel_panel_destroy_backlight(struct drm_connector *connector)
1102 {
1103         struct intel_connector *intel_connector = to_intel_connector(connector);
1104         struct intel_panel *panel = &intel_connector->panel;
1105
1106         panel->backlight.present = false;
1107         intel_backlight_device_unregister(intel_connector);
1108 }
1109
1110 /**
1111  * intel_find_panel_downclock - find the reduced downclock for LVDS in EDID
1112  * @dev: drm device
1113  * @fixed_mode : panel native mode
1114  * @connector: LVDS/eDP connector
1115  *
1116  * Return downclock_avail
1117  * Find the reduced downclock for LVDS/eDP in EDID.
1118  */
1119 struct drm_display_mode *
1120 intel_find_panel_downclock(struct drm_device *dev,
1121                         struct drm_display_mode *fixed_mode,
1122                         struct drm_connector *connector)
1123 {
1124         struct drm_display_mode *scan, *tmp_mode;
1125         int temp_downclock;
1126
1127         temp_downclock = fixed_mode->clock;
1128         tmp_mode = NULL;
1129
1130         list_for_each_entry(scan, &connector->probed_modes, head) {
1131                 /*
1132                  * If one mode has the same resolution with the fixed_panel
1133                  * mode while they have the different refresh rate, it means
1134                  * that the reduced downclock is found. In such
1135                  * case we can set the different FPx0/1 to dynamically select
1136                  * between low and high frequency.
1137                  */
1138                 if (scan->hdisplay == fixed_mode->hdisplay &&
1139                     scan->hsync_start == fixed_mode->hsync_start &&
1140                     scan->hsync_end == fixed_mode->hsync_end &&
1141                     scan->htotal == fixed_mode->htotal &&
1142                     scan->vdisplay == fixed_mode->vdisplay &&
1143                     scan->vsync_start == fixed_mode->vsync_start &&
1144                     scan->vsync_end == fixed_mode->vsync_end &&
1145                     scan->vtotal == fixed_mode->vtotal) {
1146                         if (scan->clock < temp_downclock) {
1147                                 /*
1148                                  * The downclock is already found. But we
1149                                  * expect to find the lower downclock.
1150                                  */
1151                                 temp_downclock = scan->clock;
1152                                 tmp_mode = scan;
1153                         }
1154                 }
1155         }
1156
1157         if (temp_downclock < fixed_mode->clock)
1158                 return drm_mode_duplicate(dev, tmp_mode);
1159         else
1160                 return NULL;
1161 }
1162
1163 /* Set up chip specific backlight functions */
1164 void intel_panel_init_backlight_funcs(struct drm_device *dev)
1165 {
1166         struct drm_i915_private *dev_priv = dev->dev_private;
1167
1168         if (IS_BROADWELL(dev)) {
1169                 dev_priv->display.setup_backlight = bdw_setup_backlight;
1170                 dev_priv->display.enable_backlight = bdw_enable_backlight;
1171                 dev_priv->display.disable_backlight = pch_disable_backlight;
1172                 dev_priv->display.set_backlight = bdw_set_backlight;
1173                 dev_priv->display.get_backlight = bdw_get_backlight;
1174         } else if (HAS_PCH_SPLIT(dev)) {
1175                 dev_priv->display.setup_backlight = pch_setup_backlight;
1176                 dev_priv->display.enable_backlight = pch_enable_backlight;
1177                 dev_priv->display.disable_backlight = pch_disable_backlight;
1178                 dev_priv->display.set_backlight = pch_set_backlight;
1179                 dev_priv->display.get_backlight = pch_get_backlight;
1180         } else if (IS_VALLEYVIEW(dev)) {
1181                 dev_priv->display.setup_backlight = vlv_setup_backlight;
1182                 dev_priv->display.enable_backlight = vlv_enable_backlight;
1183                 dev_priv->display.disable_backlight = vlv_disable_backlight;
1184                 dev_priv->display.set_backlight = vlv_set_backlight;
1185                 dev_priv->display.get_backlight = vlv_get_backlight;
1186         } else if (IS_GEN4(dev)) {
1187                 dev_priv->display.setup_backlight = i965_setup_backlight;
1188                 dev_priv->display.enable_backlight = i965_enable_backlight;
1189                 dev_priv->display.disable_backlight = i965_disable_backlight;
1190                 dev_priv->display.set_backlight = i9xx_set_backlight;
1191                 dev_priv->display.get_backlight = i9xx_get_backlight;
1192         } else {
1193                 dev_priv->display.setup_backlight = i9xx_setup_backlight;
1194                 dev_priv->display.enable_backlight = i9xx_enable_backlight;
1195                 dev_priv->display.disable_backlight = i9xx_disable_backlight;
1196                 dev_priv->display.set_backlight = i9xx_set_backlight;
1197                 dev_priv->display.get_backlight = i9xx_get_backlight;
1198         }
1199 }
1200
1201 int intel_panel_init(struct intel_panel *panel,
1202                      struct drm_display_mode *fixed_mode)
1203 {
1204         panel->fixed_mode = fixed_mode;
1205
1206         return 0;
1207 }
1208
1209 void intel_panel_fini(struct intel_panel *panel)
1210 {
1211         struct intel_connector *intel_connector =
1212                 container_of(panel, struct intel_connector, panel);
1213
1214         if (panel->fixed_mode)
1215                 drm_mode_destroy(intel_connector->base.dev, panel->fixed_mode);
1216
1217         if (panel->downclock_mode)
1218                 drm_mode_destroy(intel_connector->base.dev,
1219                                 panel->downclock_mode);
1220 }