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/kernel.h>
  34 #include <linux/moduleparam.h>
  35 #include "intel_drv.h"
  36
  37 void
  38 intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode,
  39                        struct drm_display_mode *adjusted_mode)
  40 {
  41         drm_mode_copy(adjusted_mode, fixed_mode);
  42
  43         drm_mode_set_crtcinfo(adjusted_mode, 0);
  44 }
  45
  46 /**
  47  * intel_find_panel_downclock - find the reduced downclock for LVDS in EDID
  48  * @dev: drm device
  49  * @fixed_mode : panel native mode
  50  * @connector: LVDS/eDP connector
  51  *
  52  * Return downclock_avail
  53  * Find the reduced downclock for LVDS/eDP in EDID.
  54  */
  55 struct drm_display_mode *
  56 intel_find_panel_downclock(struct drm_device *dev,
  57                         struct drm_display_mode *fixed_mode,
  58                         struct drm_connector *connector)
  59 {
  60         struct drm_display_mode *scan, *tmp_mode;
  61         int temp_downclock;
  62
  63         temp_downclock = fixed_mode->clock;
  64         tmp_mode = NULL;
  65
  66         list_for_each_entry(scan, &connector->probed_modes, head) {
  67                 /*
  68                  * If one mode has the same resolution with the fixed_panel
  69                  * mode while they have the different refresh rate, it means
  70                  * that the reduced downclock is found. In such
  71                  * case we can set the different FPx0/1 to dynamically select
  72                  * between low and high frequency.
  73                  */
  74                 if (scan->hdisplay == fixed_mode->hdisplay &&
  75                     scan->hsync_start == fixed_mode->hsync_start &&
  76                     scan->hsync_end == fixed_mode->hsync_end &&
  77                     scan->htotal == fixed_mode->htotal &&
  78                     scan->vdisplay == fixed_mode->vdisplay &&
  79                     scan->vsync_start == fixed_mode->vsync_start &&
  80                     scan->vsync_end == fixed_mode->vsync_end &&
  81                     scan->vtotal == fixed_mode->vtotal) {
  82                         if (scan->clock < temp_downclock) {
  83                                 /*
  84                                  * The downclock is already found. But we
  85                                  * expect to find the lower downclock.
  86                                  */
  87                                 temp_downclock = scan->clock;
  88                                 tmp_mode = scan;
  89                         }
  90                 }
  91         }
  92
  93         if (temp_downclock < fixed_mode->clock)
  94                 return drm_mode_duplicate(dev, tmp_mode);
  95         else
  96                 return NULL;
  97 }
  98
  99 /* adjusted_mode has been preset to be the panel's fixed mode */
 100 void
 101 intel_pch_panel_fitting(struct intel_crtc *intel_crtc,
 102                         struct intel_crtc_state *pipe_config,
 103                         int fitting_mode)
 104 {
 105         struct drm_display_mode *adjusted_mode;
 106         int x, y, width, height;
 107
 108         adjusted_mode = &pipe_config->base.adjusted_mode;
 109
 110         x = y = width = height = 0;
 111
 112         /* Native modes don't need fitting */
 113         if (adjusted_mode->hdisplay == pipe_config->pipe_src_w &&
 114             adjusted_mode->vdisplay == pipe_config->pipe_src_h)
 115                 goto done;
 116
 117         switch (fitting_mode) {
 118         case DRM_MODE_SCALE_CENTER:
 119                 width = pipe_config->pipe_src_w;
 120                 height = pipe_config->pipe_src_h;
 121                 x = (adjusted_mode->hdisplay - width + 1)/2;
 122                 y = (adjusted_mode->vdisplay - height + 1)/2;
 123                 break;
 124
 125         case DRM_MODE_SCALE_ASPECT:
 126                 /* Scale but preserve the aspect ratio */
 127                 {
 128                         u32 scaled_width = adjusted_mode->hdisplay
 129                                 * pipe_config->pipe_src_h;
 130                         u32 scaled_height = pipe_config->pipe_src_w
 131                                 * adjusted_mode->vdisplay;
 132                         if (scaled_width > scaled_height) { /* pillar */
 133                                 width = scaled_height / pipe_config->pipe_src_h;
 134                                 if (width & 1)
 135                                         width++;
 136                                 x = (adjusted_mode->hdisplay - width + 1) / 2;
 137                                 y = 0;
 138                                 height = adjusted_mode->vdisplay;
 139                         } else if (scaled_width < scaled_height) { /* letter */
 140                                 height = scaled_width / pipe_config->pipe_src_w;
 141                                 if (height & 1)
 142                                     height++;
 143                                 y = (adjusted_mode->vdisplay - height + 1) / 2;
 144                                 x = 0;
 145                                 width = adjusted_mode->hdisplay;
 146                         } else {
 147                                 x = y = 0;
 148                                 width = adjusted_mode->hdisplay;
 149                                 height = adjusted_mode->vdisplay;
 150                         }
 151                 }
 152                 break;
 153
 154         case DRM_MODE_SCALE_FULLSCREEN:
 155                 x = y = 0;
 156                 width = adjusted_mode->hdisplay;
 157                 height = adjusted_mode->vdisplay;
 158                 break;
 159
 160         default:
 161                 WARN(1, "bad panel fit mode: %d\n", fitting_mode);
 162                 return;
 163         }
 164
 165 done:
 166         pipe_config->pch_pfit.pos = (x << 16) | y;
 167         pipe_config->pch_pfit.size = (width << 16) | height;
 168         pipe_config->pch_pfit.enabled = pipe_config->pch_pfit.size != 0;
 169 }
 170
 171 static void
 172 centre_horizontally(struct drm_display_mode *mode,
 173                     int width)
 174 {
 175         u32 border, sync_pos, blank_width, sync_width;
 176
 177         /* keep the hsync and hblank widths constant */
 178         sync_width = mode->crtc_hsync_end - mode->crtc_hsync_start;
 179         blank_width = mode->crtc_hblank_end - mode->crtc_hblank_start;
 180         sync_pos = (blank_width - sync_width + 1) / 2;
 181
 182         border = (mode->hdisplay - width + 1) / 2;
 183         border += border & 1; /* make the border even */
 184
 185         mode->crtc_hdisplay = width;
 186         mode->crtc_hblank_start = width + border;
 187         mode->crtc_hblank_end = mode->crtc_hblank_start + blank_width;
 188
 189         mode->crtc_hsync_start = mode->crtc_hblank_start + sync_pos;
 190         mode->crtc_hsync_end = mode->crtc_hsync_start + sync_width;
 191 }
 192
 193 static void
 194 centre_vertically(struct drm_display_mode *mode,
 195                   int height)
 196 {
 197         u32 border, sync_pos, blank_width, sync_width;
 198
 199         /* keep the vsync and vblank widths constant */
 200         sync_width = mode->crtc_vsync_end - mode->crtc_vsync_start;
 201         blank_width = mode->crtc_vblank_end - mode->crtc_vblank_start;
 202         sync_pos = (blank_width - sync_width + 1) / 2;
 203
 204         border = (mode->vdisplay - height + 1) / 2;
 205
 206         mode->crtc_vdisplay = height;
 207         mode->crtc_vblank_start = height + border;
 208         mode->crtc_vblank_end = mode->crtc_vblank_start + blank_width;
 209
 210         mode->crtc_vsync_start = mode->crtc_vblank_start + sync_pos;
 211         mode->crtc_vsync_end = mode->crtc_vsync_start + sync_width;
 212 }
 213
 214 static inline u32 panel_fitter_scaling(u32 source, u32 target)
 215 {
 216         /*
 217          * Floating point operation is not supported. So the FACTOR
 218          * is defined, which can avoid the floating point computation
 219          * when calculating the panel ratio.
 220          */
 221 #define ACCURACY 12
 222 #define FACTOR (1 << ACCURACY)
 223         u32 ratio = source * FACTOR / target;
 224         return (FACTOR * ratio + FACTOR/2) / FACTOR;
 225 }
 226
 227 static void i965_scale_aspect(struct intel_crtc_state *pipe_config,
 228                               u32 *pfit_control)
 229 {
 230         struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
 231         u32 scaled_width = adjusted_mode->hdisplay *
 232                 pipe_config->pipe_src_h;
 233         u32 scaled_height = pipe_config->pipe_src_w *
 234                 adjusted_mode->vdisplay;
 235
 236         /* 965+ is easy, it does everything in hw */
 237         if (scaled_width > scaled_height)
 238                 *pfit_control |= PFIT_ENABLE |
 239                         PFIT_SCALING_PILLAR;
 240         else if (scaled_width < scaled_height)
 241                 *pfit_control |= PFIT_ENABLE |
 242                         PFIT_SCALING_LETTER;
 243         else if (adjusted_mode->hdisplay != pipe_config->pipe_src_w)
 244                 *pfit_control |= PFIT_ENABLE | PFIT_SCALING_AUTO;
 245 }
 246
 247 static void i9xx_scale_aspect(struct intel_crtc_state *pipe_config,
 248                               u32 *pfit_control, u32 *pfit_pgm_ratios,
 249                               u32 *border)
 250 {
 251         struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
 252         u32 scaled_width = adjusted_mode->hdisplay *
 253                 pipe_config->pipe_src_h;
 254         u32 scaled_height = pipe_config->pipe_src_w *
 255                 adjusted_mode->vdisplay;
 256         u32 bits;
 257
 258         /*
 259          * For earlier chips we have to calculate the scaling
 260          * ratio by hand and program it into the
 261          * PFIT_PGM_RATIO register
 262          */
 263         if (scaled_width > scaled_height) { /* pillar */
 264                 centre_horizontally(adjusted_mode,
 265                                     scaled_height /
 266                                     pipe_config->pipe_src_h);
 267
 268                 *border = LVDS_BORDER_ENABLE;
 269                 if (pipe_config->pipe_src_h != adjusted_mode->vdisplay) {
 270                         bits = panel_fitter_scaling(pipe_config->pipe_src_h,
 271                                                     adjusted_mode->vdisplay);
 272
 273                         *pfit_pgm_ratios |= (bits << PFIT_HORIZ_SCALE_SHIFT |
 274                                              bits << PFIT_VERT_SCALE_SHIFT);
 275                         *pfit_control |= (PFIT_ENABLE |
 276                                           VERT_INTERP_BILINEAR |
 277                                           HORIZ_INTERP_BILINEAR);
 278                 }
 279         } else if (scaled_width < scaled_height) { /* letter */
 280                 centre_vertically(adjusted_mode,
 281                                   scaled_width /
 282                                   pipe_config->pipe_src_w);
 283
 284                 *border = LVDS_BORDER_ENABLE;
 285                 if (pipe_config->pipe_src_w != adjusted_mode->hdisplay) {
 286                         bits = panel_fitter_scaling(pipe_config->pipe_src_w,
 287                                                     adjusted_mode->hdisplay);
 288
 289                         *pfit_pgm_ratios |= (bits << PFIT_HORIZ_SCALE_SHIFT |
 290                                              bits << PFIT_VERT_SCALE_SHIFT);
 291                         *pfit_control |= (PFIT_ENABLE |
 292                                           VERT_INTERP_BILINEAR |
 293                                           HORIZ_INTERP_BILINEAR);
 294                 }
 295         } else {
 296                 /* Aspects match, Let hw scale both directions */
 297                 *pfit_control |= (PFIT_ENABLE |
 298                                   VERT_AUTO_SCALE | HORIZ_AUTO_SCALE |
 299                                   VERT_INTERP_BILINEAR |
 300                                   HORIZ_INTERP_BILINEAR);
 301         }
 302 }
 303
 304 void intel_gmch_panel_fitting(struct intel_crtc *intel_crtc,
 305                               struct intel_crtc_state *pipe_config,
 306                               int fitting_mode)
 307 {
 308         struct drm_device *dev = intel_crtc->base.dev;
 309         u32 pfit_control = 0, pfit_pgm_ratios = 0, border = 0;
 310         struct drm_display_mode *adjusted_mode;
 311
 312         adjusted_mode = &pipe_config->base.adjusted_mode;
 313
 314         /* Native modes don't need fitting */
 315         if (adjusted_mode->hdisplay == pipe_config->pipe_src_w &&
 316             adjusted_mode->vdisplay == pipe_config->pipe_src_h)
 317                 goto out;
 318
 319         switch (fitting_mode) {
 320         case DRM_MODE_SCALE_CENTER:
 321                 /*
 322                  * For centered modes, we have to calculate border widths &
 323                  * heights and modify the values programmed into the CRTC.
 324                  */
 325                 centre_horizontally(adjusted_mode, pipe_config->pipe_src_w);
 326                 centre_vertically(adjusted_mode, pipe_config->pipe_src_h);
 327                 border = LVDS_BORDER_ENABLE;
 328                 break;
 329         case DRM_MODE_SCALE_ASPECT:
 330                 /* Scale but preserve the aspect ratio */
 331                 if (INTEL_INFO(dev)->gen >= 4)
 332                         i965_scale_aspect(pipe_config, &pfit_control);
 333                 else
 334                         i9xx_scale_aspect(pipe_config, &pfit_control,
 335                                           &pfit_pgm_ratios, &border);
 336                 break;
 337         case DRM_MODE_SCALE_FULLSCREEN:
 338                 /*
 339                  * Full scaling, even if it changes the aspect ratio.
 340                  * Fortunately this is all done for us in hw.
 341                  */
 342                 if (pipe_config->pipe_src_h != adjusted_mode->vdisplay ||
 343                     pipe_config->pipe_src_w != adjusted_mode->hdisplay) {
 344                         pfit_control |= PFIT_ENABLE;
 345                         if (INTEL_INFO(dev)->gen >= 4)
 346                                 pfit_control |= PFIT_SCALING_AUTO;
 347                         else
 348                                 pfit_control |= (VERT_AUTO_SCALE |
 349                                                  VERT_INTERP_BILINEAR |
 350                                                  HORIZ_AUTO_SCALE |
 351                                                  HORIZ_INTERP_BILINEAR);
 352                 }
 353                 break;
 354         default:
 355                 WARN(1, "bad panel fit mode: %d\n", fitting_mode);
 356                 return;
 357         }
 358
 359         /* 965+ wants fuzzy fitting */
 360         /* FIXME: handle multiple panels by failing gracefully */
 361         if (INTEL_INFO(dev)->gen >= 4)
 362                 pfit_control |= ((intel_crtc->pipe << PFIT_PIPE_SHIFT) |
 363                                  PFIT_FILTER_FUZZY);
 364
 365 out:
 366         if ((pfit_control & PFIT_ENABLE) == 0) {
 367                 pfit_control = 0;
 368                 pfit_pgm_ratios = 0;
 369         }
 370
 371         /* Make sure pre-965 set dither correctly for 18bpp panels. */
 372         if (INTEL_INFO(dev)->gen < 4 && pipe_config->pipe_bpp == 18)
 373                 pfit_control |= PANEL_8TO6_DITHER_ENABLE;
 374
 375         pipe_config->gmch_pfit.control = pfit_control;
 376         pipe_config->gmch_pfit.pgm_ratios = pfit_pgm_ratios;
 377         pipe_config->gmch_pfit.lvds_border_bits = border;
 378 }
 379
 380 enum drm_connector_status
 381 intel_panel_detect(struct drm_device *dev)
 382 {
 383         struct drm_i915_private *dev_priv = dev->dev_private;
 384
 385         /* Assume that the BIOS does not lie through the OpRegion... */
 386         if (!i915.panel_ignore_lid && dev_priv->opregion.lid_state) {
 387                 return ioread32(dev_priv->opregion.lid_state) & 0x1 ?
 388                         connector_status_connected :
 389                         connector_status_disconnected;
 390         }
 391
 392         switch (i915.panel_ignore_lid) {
 393         case -2:
 394                 return connector_status_connected;
 395         case -1:
 396                 return connector_status_disconnected;
 397         default:
 398                 return connector_status_unknown;
 399         }
 400 }
 401
 402 /**
 403  * scale - scale values from one range to another
 404  *
 405  * @source_val: value in range [@source_min..@source_max]
 406  *
 407  * Return @source_val in range [@source_min..@source_max] scaled to range
 408  * [@target_min..@target_max].
 409  */
 410 static uint32_t scale(uint32_t source_val,
 411                       uint32_t source_min, uint32_t source_max,
 412                       uint32_t target_min, uint32_t target_max)
 413 {
 414         uint64_t target_val;
 415
 416         WARN_ON(source_min > source_max);
 417         WARN_ON(target_min > target_max);
 418
 419         /* defensive */
 420         source_val = clamp(source_val, source_min, source_max);
 421
 422         /* avoid overflows */
 423         target_val = DIV_ROUND_CLOSEST_ULL((uint64_t)(source_val - source_min) *
 424                         (target_max - target_min), source_max - source_min);
 425         target_val += target_min;
 426
 427         return target_val;
 428 }
 429
 430 /* Scale user_level in range [0..user_max] to [hw_min..hw_max]. */
 431 static inline u32 scale_user_to_hw(struct intel_connector *connector,
 432                                    u32 user_level, u32 user_max)
 433 {
 434         struct intel_panel *panel = &connector->panel;
 435
 436         return scale(user_level, 0, user_max,
 437                      panel->backlight.min, panel->backlight.max);
 438 }
 439
 440 /* Scale user_level in range [0..user_max] to [0..hw_max], clamping the result
 441  * to [hw_min..hw_max]. */
 442 static inline u32 clamp_user_to_hw(struct intel_connector *connector,
 443                                    u32 user_level, u32 user_max)
 444 {
 445         struct intel_panel *panel = &connector->panel;
 446         u32 hw_level;
 447
 448         hw_level = scale(user_level, 0, user_max, 0, panel->backlight.max);
 449         hw_level = clamp(hw_level, panel->backlight.min, panel->backlight.max);
 450
 451         return hw_level;
 452 }
 453
 454 /* Scale hw_level in range [hw_min..hw_max] to [0..user_max]. */
 455 static inline u32 scale_hw_to_user(struct intel_connector *connector,
 456                                    u32 hw_level, u32 user_max)
 457 {
 458         struct intel_panel *panel = &connector->panel;
 459
 460         return scale(hw_level, panel->backlight.min, panel->backlight.max,
 461                      0, user_max);
 462 }
 463
 464 static u32 intel_panel_compute_brightness(struct intel_connector *connector,
 465                                           u32 val)
 466 {
 467         struct drm_device *dev = connector->base.dev;
 468         struct drm_i915_private *dev_priv = dev->dev_private;
 469         struct intel_panel *panel = &connector->panel;
 470
 471         WARN_ON(panel->backlight.max == 0);
 472
 473         if (i915.invert_brightness < 0)
 474                 return val;
 475
 476         if (i915.invert_brightness > 0 ||
 477             dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
 478                 return panel->backlight.max - val;
 479         }
 480
 481         return val;
 482 }
 483
 484 static u32 bdw_get_backlight(struct intel_connector *connector)
 485 {
 486         struct drm_device *dev = connector->base.dev;
 487         struct drm_i915_private *dev_priv = dev->dev_private;
 488
 489         return I915_READ(BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
 490 }
 491
 492 static u32 pch_get_backlight(struct intel_connector *connector)
 493 {
 494         struct drm_device *dev = connector->base.dev;
 495         struct drm_i915_private *dev_priv = dev->dev_private;
 496
 497         return I915_READ(BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
 498 }
 499
 500 static u32 i9xx_get_backlight(struct intel_connector *connector)
 501 {
 502         struct drm_device *dev = connector->base.dev;
 503         struct drm_i915_private *dev_priv = dev->dev_private;
 504         struct intel_panel *panel = &connector->panel;
 505         u32 val;
 506
 507         val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
 508         if (INTEL_INFO(dev)->gen < 4)
 509                 val >>= 1;
 510
 511         if (panel->backlight.combination_mode) {
 512                 u8 lbpc;
 513
 514                 pci_read_config_byte(dev->pdev, PCI_LBPC, &lbpc);
 515                 val *= lbpc;
 516         }
 517
 518         return val;
 519 }
 520
 521 static u32 _vlv_get_backlight(struct drm_device *dev, enum pipe pipe)
 522 {
 523         struct drm_i915_private *dev_priv = dev->dev_private;
 524
 525         if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
 526                 return 0;
 527
 528         return I915_READ(VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
 529 }
 530
 531 static u32 vlv_get_backlight(struct intel_connector *connector)
 532 {
 533         struct drm_device *dev = connector->base.dev;
 534         enum pipe pipe = intel_get_pipe_from_connector(connector);
 535
 536         return _vlv_get_backlight(dev, pipe);
 537 }
 538
 539 static u32 bxt_get_backlight(struct intel_connector *connector)
 540 {
 541         struct drm_device *dev = connector->base.dev;
 542         struct drm_i915_private *dev_priv = dev->dev_private;
 543
 544         return I915_READ(BXT_BLC_PWM_DUTY1);
 545 }
 546
 547 static u32 intel_panel_get_backlight(struct intel_connector *connector)
 548 {
 549         struct drm_device *dev = connector->base.dev;
 550         struct drm_i915_private *dev_priv = dev->dev_private;
 551         struct intel_panel *panel = &connector->panel;
 552         u32 val = 0;
 553
 554         mutex_lock(&dev_priv->backlight_lock);
 555
 556         if (panel->backlight.enabled) {
 557                 val = dev_priv->display.get_backlight(connector);
 558                 val = intel_panel_compute_brightness(connector, val);
 559         }
 560
 561         mutex_unlock(&dev_priv->backlight_lock);
 562
 563         DRM_DEBUG_DRIVER("get backlight PWM = %d\n", val);
 564         return val;
 565 }
 566
 567 static void bdw_set_backlight(struct intel_connector *connector, u32 level)
 568 {
 569         struct drm_device *dev = connector->base.dev;
 570         struct drm_i915_private *dev_priv = dev->dev_private;
 571         u32 val = I915_READ(BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 572         I915_WRITE(BLC_PWM_PCH_CTL2, val | level);
 573 }
 574
 575 static void pch_set_backlight(struct intel_connector *connector, u32 level)
 576 {
 577         struct drm_device *dev = connector->base.dev;
 578         struct drm_i915_private *dev_priv = dev->dev_private;
 579         u32 tmp;
 580
 581         tmp = I915_READ(BLC_PWM_CPU_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 582         I915_WRITE(BLC_PWM_CPU_CTL, tmp | level);
 583 }
 584
 585 static void i9xx_set_backlight(struct intel_connector *connector, u32 level)
 586 {
 587         struct drm_device *dev = connector->base.dev;
 588         struct drm_i915_private *dev_priv = dev->dev_private;
 589         struct intel_panel *panel = &connector->panel;
 590         u32 tmp, mask;
 591
 592         WARN_ON(panel->backlight.max == 0);
 593
 594         if (panel->backlight.combination_mode) {
 595                 u8 lbpc;
 596
 597                 lbpc = level * 0xfe / panel->backlight.max + 1;
 598                 level /= lbpc;
 599                 pci_write_config_byte(dev->pdev, PCI_LBPC, lbpc);
 600         }
 601
 602         if (IS_GEN4(dev)) {
 603                 mask = BACKLIGHT_DUTY_CYCLE_MASK;
 604         } else {
 605                 level <<= 1;
 606                 mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV;
 607         }
 608
 609         tmp = I915_READ(BLC_PWM_CTL) & ~mask;
 610         I915_WRITE(BLC_PWM_CTL, tmp | level);
 611 }
 612
 613 static void vlv_set_backlight(struct intel_connector *connector, u32 level)
 614 {
 615         struct drm_device *dev = connector->base.dev;
 616         struct drm_i915_private *dev_priv = dev->dev_private;
 617         enum pipe pipe = intel_get_pipe_from_connector(connector);
 618         u32 tmp;
 619
 620         if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
 621                 return;
 622
 623         tmp = I915_READ(VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 624         I915_WRITE(VLV_BLC_PWM_CTL(pipe), tmp | level);
 625 }
 626
 627 static void bxt_set_backlight(struct intel_connector *connector, u32 level)
 628 {
 629         struct drm_device *dev = connector->base.dev;
 630         struct drm_i915_private *dev_priv = dev->dev_private;
 631
 632         I915_WRITE(BXT_BLC_PWM_DUTY1, level);
 633 }
 634
 635 static void
 636 intel_panel_actually_set_backlight(struct intel_connector *connector, u32 level)
 637 {
 638         struct drm_device *dev = connector->base.dev;
 639         struct drm_i915_private *dev_priv = dev->dev_private;
 640
 641         DRM_DEBUG_DRIVER("set backlight PWM = %d\n", level);
 642
 643         level = intel_panel_compute_brightness(connector, level);
 644         dev_priv->display.set_backlight(connector, level);
 645 }
 646
 647 /* set backlight brightness to level in range [0..max], scaling wrt hw min */
 648 static void intel_panel_set_backlight(struct intel_connector *connector,
 649                                       u32 user_level, u32 user_max)
 650 {
 651         struct drm_device *dev = connector->base.dev;
 652         struct drm_i915_private *dev_priv = dev->dev_private;
 653         struct intel_panel *panel = &connector->panel;
 654         u32 hw_level;
 655
 656         if (!panel->backlight.present)
 657                 return;
 658
 659         mutex_lock(&dev_priv->backlight_lock);
 660
 661         WARN_ON(panel->backlight.max == 0);
 662
 663         hw_level = scale_user_to_hw(connector, user_level, user_max);
 664         panel->backlight.level = hw_level;
 665
 666         if (panel->backlight.enabled)
 667                 intel_panel_actually_set_backlight(connector, hw_level);
 668
 669         mutex_unlock(&dev_priv->backlight_lock);
 670 }
 671
 672 /* set backlight brightness to level in range [0..max], assuming hw min is
 673  * respected.
 674  */
 675 void intel_panel_set_backlight_acpi(struct intel_connector *connector,
 676                                     u32 user_level, u32 user_max)
 677 {
 678         struct drm_device *dev = connector->base.dev;
 679         struct drm_i915_private *dev_priv = dev->dev_private;
 680         struct intel_panel *panel = &connector->panel;
 681         enum pipe pipe = intel_get_pipe_from_connector(connector);
 682         u32 hw_level;
 683
 684         /*
 685          * INVALID_PIPE may occur during driver init because
 686          * connection_mutex isn't held across the entire backlight
 687          * setup + modeset readout, and the BIOS can issue the
 688          * requests at any time.
 689          */
 690         if (!panel->backlight.present || pipe == INVALID_PIPE)
 691                 return;
 692
 693         mutex_lock(&dev_priv->backlight_lock);
 694
 695         WARN_ON(panel->backlight.max == 0);
 696
 697         hw_level = clamp_user_to_hw(connector, user_level, user_max);
 698         panel->backlight.level = hw_level;
 699
 700         if (panel->backlight.device)
 701                 panel->backlight.device->props.brightness =
 702                         scale_hw_to_user(connector,
 703                                          panel->backlight.level,
 704                                          panel->backlight.device->props.max_brightness);
 705
 706         if (panel->backlight.enabled)
 707                 intel_panel_actually_set_backlight(connector, hw_level);
 708
 709         mutex_unlock(&dev_priv->backlight_lock);
 710 }
 711
 712 static void pch_disable_backlight(struct intel_connector *connector)
 713 {
 714         struct drm_device *dev = connector->base.dev;
 715         struct drm_i915_private *dev_priv = dev->dev_private;
 716         u32 tmp;
 717
 718         intel_panel_actually_set_backlight(connector, 0);
 719
 720         tmp = I915_READ(BLC_PWM_CPU_CTL2);
 721         I915_WRITE(BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
 722
 723         tmp = I915_READ(BLC_PWM_PCH_CTL1);
 724         I915_WRITE(BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
 725 }
 726
 727 static void i9xx_disable_backlight(struct intel_connector *connector)
 728 {
 729         intel_panel_actually_set_backlight(connector, 0);
 730 }
 731
 732 static void i965_disable_backlight(struct intel_connector *connector)
 733 {
 734         struct drm_device *dev = connector->base.dev;
 735         struct drm_i915_private *dev_priv = dev->dev_private;
 736         u32 tmp;
 737
 738         intel_panel_actually_set_backlight(connector, 0);
 739
 740         tmp = I915_READ(BLC_PWM_CTL2);
 741         I915_WRITE(BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
 742 }
 743
 744 static void vlv_disable_backlight(struct intel_connector *connector)
 745 {
 746         struct drm_device *dev = connector->base.dev;
 747         struct drm_i915_private *dev_priv = dev->dev_private;
 748         enum pipe pipe = intel_get_pipe_from_connector(connector);
 749         u32 tmp;
 750
 751         if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
 752                 return;
 753
 754         intel_panel_actually_set_backlight(connector, 0);
 755
 756         tmp = I915_READ(VLV_BLC_PWM_CTL2(pipe));
 757         I915_WRITE(VLV_BLC_PWM_CTL2(pipe), tmp & ~BLM_PWM_ENABLE);
 758 }
 759
 760 static void bxt_disable_backlight(struct intel_connector *connector)
 761 {
 762         struct drm_device *dev = connector->base.dev;
 763         struct drm_i915_private *dev_priv = dev->dev_private;
 764         u32 tmp;
 765
 766         intel_panel_actually_set_backlight(connector, 0);
 767
 768         tmp = I915_READ(BXT_BLC_PWM_CTL1);
 769         I915_WRITE(BXT_BLC_PWM_CTL1, tmp & ~BXT_BLC_PWM_ENABLE);
 770 }
 771
 772 void intel_panel_disable_backlight(struct intel_connector *connector)
 773 {
 774         struct drm_device *dev = connector->base.dev;
 775         struct drm_i915_private *dev_priv = dev->dev_private;
 776         struct intel_panel *panel = &connector->panel;
 777
 778         if (!panel->backlight.present)
 779                 return;
 780
 781         /*
 782          * Do not disable backlight on the vgaswitcheroo path. When switching
 783          * away from i915, the other client may depend on i915 to handle the
 784          * backlight. This will leave the backlight on unnecessarily when
 785          * another client is not activated.
 786          */
 787         if (dev->switch_power_state == DRM_SWITCH_POWER_CHANGING) {
 788                 DRM_DEBUG_DRIVER("Skipping backlight disable on vga switch\n");
 789                 return;
 790         }
 791
 792         mutex_lock(&dev_priv->backlight_lock);
 793
 794         if (panel->backlight.device)
 795                 panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
 796         panel->backlight.enabled = false;
 797         dev_priv->display.disable_backlight(connector);
 798
 799         mutex_unlock(&dev_priv->backlight_lock);
 800 }
 801
 802 static void bdw_enable_backlight(struct intel_connector *connector)
 803 {
 804         struct drm_device *dev = connector->base.dev;
 805         struct drm_i915_private *dev_priv = dev->dev_private;
 806         struct intel_panel *panel = &connector->panel;
 807         u32 pch_ctl1, pch_ctl2;
 808
 809         pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
 810         if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
 811                 DRM_DEBUG_KMS("pch backlight already enabled\n");
 812                 pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
 813                 I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
 814         }
 815
 816         pch_ctl2 = panel->backlight.max << 16;
 817         I915_WRITE(BLC_PWM_PCH_CTL2, pch_ctl2);
 818
 819         pch_ctl1 = 0;
 820         if (panel->backlight.active_low_pwm)
 821                 pch_ctl1 |= BLM_PCH_POLARITY;
 822
 823         /* After LPT, override is the default. */
 824         if (HAS_PCH_LPT(dev_priv))
 825                 pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
 826
 827         I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
 828         POSTING_READ(BLC_PWM_PCH_CTL1);
 829         I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
 830
 831         /* This won't stick until the above enable. */
 832         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 833 }
 834
 835 static void pch_enable_backlight(struct intel_connector *connector)
 836 {
 837         struct drm_device *dev = connector->base.dev;
 838         struct drm_i915_private *dev_priv = dev->dev_private;
 839         struct intel_panel *panel = &connector->panel;
 840         enum pipe pipe = intel_get_pipe_from_connector(connector);
 841         enum transcoder cpu_transcoder =
 842                 intel_pipe_to_cpu_transcoder(dev_priv, pipe);
 843         u32 cpu_ctl2, pch_ctl1, pch_ctl2;
 844
 845         cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
 846         if (cpu_ctl2 & BLM_PWM_ENABLE) {
 847                 DRM_DEBUG_KMS("cpu backlight already enabled\n");
 848                 cpu_ctl2 &= ~BLM_PWM_ENABLE;
 849                 I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2);
 850         }
 851
 852         pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
 853         if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
 854                 DRM_DEBUG_KMS("pch backlight already enabled\n");
 855                 pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
 856                 I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
 857         }
 858
 859         if (cpu_transcoder == TRANSCODER_EDP)
 860                 cpu_ctl2 = BLM_TRANSCODER_EDP;
 861         else
 862                 cpu_ctl2 = BLM_PIPE(cpu_transcoder);
 863         I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2);
 864         POSTING_READ(BLC_PWM_CPU_CTL2);
 865         I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
 866
 867         /* This won't stick until the above enable. */
 868         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 869
 870         pch_ctl2 = panel->backlight.max << 16;
 871         I915_WRITE(BLC_PWM_PCH_CTL2, pch_ctl2);
 872
 873         pch_ctl1 = 0;
 874         if (panel->backlight.active_low_pwm)
 875                 pch_ctl1 |= BLM_PCH_POLARITY;
 876
 877         I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
 878         POSTING_READ(BLC_PWM_PCH_CTL1);
 879         I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
 880 }
 881
 882 static void i9xx_enable_backlight(struct intel_connector *connector)
 883 {
 884         struct drm_device *dev = connector->base.dev;
 885         struct drm_i915_private *dev_priv = dev->dev_private;
 886         struct intel_panel *panel = &connector->panel;
 887         u32 ctl, freq;
 888
 889         ctl = I915_READ(BLC_PWM_CTL);
 890         if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
 891                 DRM_DEBUG_KMS("backlight already enabled\n");
 892                 I915_WRITE(BLC_PWM_CTL, 0);
 893         }
 894
 895         freq = panel->backlight.max;
 896         if (panel->backlight.combination_mode)
 897                 freq /= 0xff;
 898
 899         ctl = freq << 17;
 900         if (panel->backlight.combination_mode)
 901                 ctl |= BLM_LEGACY_MODE;
 902         if (IS_PINEVIEW(dev) && panel->backlight.active_low_pwm)
 903                 ctl |= BLM_POLARITY_PNV;
 904
 905         I915_WRITE(BLC_PWM_CTL, ctl);
 906         POSTING_READ(BLC_PWM_CTL);
 907
 908         /* XXX: combine this into above write? */
 909         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 910
 911         /*
 912          * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is
 913          * 855gm only, but checking for gen2 is safe, as 855gm is the only gen2
 914          * that has backlight.
 915          */
 916         if (IS_GEN2(dev))
 917                 I915_WRITE(BLC_HIST_CTL, BLM_HISTOGRAM_ENABLE);
 918 }
 919
 920 static void i965_enable_backlight(struct intel_connector *connector)
 921 {
 922         struct drm_device *dev = connector->base.dev;
 923         struct drm_i915_private *dev_priv = dev->dev_private;
 924         struct intel_panel *panel = &connector->panel;
 925         enum pipe pipe = intel_get_pipe_from_connector(connector);
 926         u32 ctl, ctl2, freq;
 927
 928         ctl2 = I915_READ(BLC_PWM_CTL2);
 929         if (ctl2 & BLM_PWM_ENABLE) {
 930                 DRM_DEBUG_KMS("backlight already enabled\n");
 931                 ctl2 &= ~BLM_PWM_ENABLE;
 932                 I915_WRITE(BLC_PWM_CTL2, ctl2);
 933         }
 934
 935         freq = panel->backlight.max;
 936         if (panel->backlight.combination_mode)
 937                 freq /= 0xff;
 938
 939         ctl = freq << 16;
 940         I915_WRITE(BLC_PWM_CTL, ctl);
 941
 942         ctl2 = BLM_PIPE(pipe);
 943         if (panel->backlight.combination_mode)
 944                 ctl2 |= BLM_COMBINATION_MODE;
 945         if (panel->backlight.active_low_pwm)
 946                 ctl2 |= BLM_POLARITY_I965;
 947         I915_WRITE(BLC_PWM_CTL2, ctl2);
 948         POSTING_READ(BLC_PWM_CTL2);
 949         I915_WRITE(BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
 950
 951         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 952 }
 953
 954 static void vlv_enable_backlight(struct intel_connector *connector)
 955 {
 956         struct drm_device *dev = connector->base.dev;
 957         struct drm_i915_private *dev_priv = dev->dev_private;
 958         struct intel_panel *panel = &connector->panel;
 959         enum pipe pipe = intel_get_pipe_from_connector(connector);
 960         u32 ctl, ctl2;
 961
 962         if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
 963                 return;
 964
 965         ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
 966         if (ctl2 & BLM_PWM_ENABLE) {
 967                 DRM_DEBUG_KMS("backlight already enabled\n");
 968                 ctl2 &= ~BLM_PWM_ENABLE;
 969                 I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
 970         }
 971
 972         ctl = panel->backlight.max << 16;
 973         I915_WRITE(VLV_BLC_PWM_CTL(pipe), ctl);
 974
 975         /* XXX: combine this into above write? */
 976         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 977
 978         ctl2 = 0;
 979         if (panel->backlight.active_low_pwm)
 980                 ctl2 |= BLM_POLARITY_I965;
 981         I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
 982         POSTING_READ(VLV_BLC_PWM_CTL2(pipe));
 983         I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2 | BLM_PWM_ENABLE);
 984 }
 985
 986 static void bxt_enable_backlight(struct intel_connector *connector)
 987 {
 988         struct drm_device *dev = connector->base.dev;
 989         struct drm_i915_private *dev_priv = dev->dev_private;
 990         struct intel_panel *panel = &connector->panel;
 991         u32 pwm_ctl;
 992
 993         pwm_ctl = I915_READ(BXT_BLC_PWM_CTL1);
 994         if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
 995                 DRM_DEBUG_KMS("backlight already enabled\n");
 996                 pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
 997                 I915_WRITE(BXT_BLC_PWM_CTL1, pwm_ctl);
 998         }
 999
1000         I915_WRITE(BXT_BLC_PWM_FREQ1, panel->backlight.max);
1001
1002         intel_panel_actually_set_backlight(connector, panel->backlight.level);
1003
1004         pwm_ctl = 0;
1005         if (panel->backlight.active_low_pwm)
1006                 pwm_ctl |= BXT_BLC_PWM_POLARITY;
1007
1008         I915_WRITE(BXT_BLC_PWM_CTL1, pwm_ctl);
1009         POSTING_READ(BXT_BLC_PWM_CTL1);
1010         I915_WRITE(BXT_BLC_PWM_CTL1, pwm_ctl | BXT_BLC_PWM_ENABLE);
1011 }
1012
1013 void intel_panel_enable_backlight(struct intel_connector *connector)
1014 {
1015         struct drm_device *dev = connector->base.dev;
1016         struct drm_i915_private *dev_priv = dev->dev_private;
1017         struct intel_panel *panel = &connector->panel;
1018         enum pipe pipe = intel_get_pipe_from_connector(connector);
1019
1020         if (!panel->backlight.present)
1021                 return;
1022
1023         DRM_DEBUG_KMS("pipe %c\n", pipe_name(pipe));
1024
1025         mutex_lock(&dev_priv->backlight_lock);
1026
1027         WARN_ON(panel->backlight.max == 0);
1028
1029         if (panel->backlight.level <= panel->backlight.min) {
1030                 panel->backlight.level = panel->backlight.max;
1031                 if (panel->backlight.device)
1032                         panel->backlight.device->props.brightness =
1033                                 scale_hw_to_user(connector,
1034                                                  panel->backlight.level,
1035                                                  panel->backlight.device->props.max_brightness);
1036         }
1037
1038         dev_priv->display.enable_backlight(connector);
1039         panel->backlight.enabled = true;
1040         if (panel->backlight.device)
1041                 panel->backlight.device->props.power = FB_BLANK_UNBLANK;
1042
1043         mutex_unlock(&dev_priv->backlight_lock);
1044 }
1045
1046 #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
1047 static int intel_backlight_device_update_status(struct backlight_device *bd)
1048 {
1049         struct intel_connector *connector = bl_get_data(bd);
1050         struct intel_panel *panel = &connector->panel;
1051         struct drm_device *dev = connector->base.dev;
1052
1053         drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
1054         DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
1055                       bd->props.brightness, bd->props.max_brightness);
1056         intel_panel_set_backlight(connector, bd->props.brightness,
1057                                   bd->props.max_brightness);
1058
1059         /*
1060          * Allow flipping bl_power as a sub-state of enabled. Sadly the
1061          * backlight class device does not make it easy to to differentiate
1062          * between callbacks for brightness and bl_power, so our backlight_power
1063          * callback needs to take this into account.
1064          */
1065         if (panel->backlight.enabled) {
1066                 if (panel->backlight_power) {
1067                         bool enable = bd->props.power == FB_BLANK_UNBLANK &&
1068                                 bd->props.brightness != 0;
1069                         panel->backlight_power(connector, enable);
1070                 }
1071         } else {
1072                 bd->props.power = FB_BLANK_POWERDOWN;
1073         }
1074
1075         drm_modeset_unlock(&dev->mode_config.connection_mutex);
1076         return 0;
1077 }
1078
1079 static int intel_backlight_device_get_brightness(struct backlight_device *bd)
1080 {
1081         struct intel_connector *connector = bl_get_data(bd);
1082         struct drm_device *dev = connector->base.dev;
1083         struct drm_i915_private *dev_priv = dev->dev_private;
1084         u32 hw_level;
1085         int ret;
1086
1087         intel_runtime_pm_get(dev_priv);
1088         drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
1089
1090         hw_level = intel_panel_get_backlight(connector);
1091         ret = scale_hw_to_user(connector, hw_level, bd->props.max_brightness);
1092
1093         drm_modeset_unlock(&dev->mode_config.connection_mutex);
1094         intel_runtime_pm_put(dev_priv);
1095
1096         return ret;
1097 }
1098
1099 static const struct backlight_ops intel_backlight_device_ops = {
1100         .update_status = intel_backlight_device_update_status,
1101         .get_brightness = intel_backlight_device_get_brightness,
1102 };
1103
1104 static int intel_backlight_device_register(struct intel_connector *connector)
1105 {
1106         struct intel_panel *panel = &connector->panel;
1107         struct backlight_properties props;
1108
1109         if (WARN_ON(panel->backlight.device))
1110                 return -ENODEV;
1111
1112         if (!panel->backlight.present)
1113                 return 0;
1114
1115         WARN_ON(panel->backlight.max == 0);
1116
1117         memset(&props, 0, sizeof(props));
1118         props.type = BACKLIGHT_RAW;
1119
1120         /*
1121          * Note: Everything should work even if the backlight device max
1122          * presented to the userspace is arbitrarily chosen.
1123          */
1124         props.max_brightness = panel->backlight.max;
1125         props.brightness = scale_hw_to_user(connector,
1126                                             panel->backlight.level,
1127                                             props.max_brightness);
1128
1129         if (panel->backlight.enabled)
1130                 props.power = FB_BLANK_UNBLANK;
1131         else
1132                 props.power = FB_BLANK_POWERDOWN;
1133
1134         /*
1135          * Note: using the same name independent of the connector prevents
1136          * registration of multiple backlight devices in the driver.
1137          */
1138         panel->backlight.device =
1139                 backlight_device_register("intel_backlight",
1140                                           connector->base.kdev,
1141                                           connector,
1142                                           &intel_backlight_device_ops, &props);
1143
1144         if (IS_ERR(panel->backlight.device)) {
1145                 DRM_ERROR("Failed to register backlight: %ld\n",
1146                           PTR_ERR(panel->backlight.device));
1147                 panel->backlight.device = NULL;
1148                 return -ENODEV;
1149         }
1150
1151         DRM_DEBUG_KMS("Connector %s backlight sysfs interface registered\n",
1152                       connector->base.name);
1153
1154         return 0;
1155 }
1156
1157 static void intel_backlight_device_unregister(struct intel_connector *connector)
1158 {
1159         struct intel_panel *panel = &connector->panel;
1160
1161         if (panel->backlight.device) {
1162                 backlight_device_unregister(panel->backlight.device);
1163                 panel->backlight.device = NULL;
1164         }
1165 }
1166 #else /* CONFIG_BACKLIGHT_CLASS_DEVICE */
1167 static int intel_backlight_device_register(struct intel_connector *connector)
1168 {
1169         return 0;
1170 }
1171 static void intel_backlight_device_unregister(struct intel_connector *connector)
1172 {
1173 }
1174 #endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
1175
1176 /*
1177  * Note: The setup hooks can't assume pipe is set!
1178  *
1179  * XXX: Query mode clock or hardware clock and program PWM modulation frequency
1180  * appropriately when it's 0. Use VBT and/or sane defaults.
1181  */
1182 static u32 get_backlight_min_vbt(struct intel_connector *connector)
1183 {
1184         struct drm_device *dev = connector->base.dev;
1185         struct drm_i915_private *dev_priv = dev->dev_private;
1186         struct intel_panel *panel = &connector->panel;
1187         int min;
1188
1189         WARN_ON(panel->backlight.max == 0);
1190
1191         /*
1192          * XXX: If the vbt value is 255, it makes min equal to max, which leads
1193          * to problems. There are such machines out there. Either our
1194          * interpretation is wrong or the vbt has bogus data. Or both. Safeguard
1195          * against this by letting the minimum be at most (arbitrarily chosen)
1196          * 25% of the max.
1197          */
1198         min = clamp_t(int, dev_priv->vbt.backlight.min_brightness, 0, 64);
1199         if (min != dev_priv->vbt.backlight.min_brightness) {
1200                 DRM_DEBUG_KMS("clamping VBT min backlight %d/255 to %d/255\n",
1201                               dev_priv->vbt.backlight.min_brightness, min);
1202         }
1203
1204         /* vbt value is a coefficient in range [0..255] */
1205         return scale(min, 0, 255, 0, panel->backlight.max);
1206 }
1207
1208 static int bdw_setup_backlight(struct intel_connector *connector, enum pipe unused)
1209 {
1210         struct drm_device *dev = connector->base.dev;
1211         struct drm_i915_private *dev_priv = dev->dev_private;
1212         struct intel_panel *panel = &connector->panel;
1213         u32 pch_ctl1, pch_ctl2, val;
1214
1215         pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
1216         panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1217
1218         pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
1219         panel->backlight.max = pch_ctl2 >> 16;
1220         if (!panel->backlight.max)
1221                 return -ENODEV;
1222
1223         panel->backlight.min = get_backlight_min_vbt(connector);
1224
1225         val = bdw_get_backlight(connector);
1226         panel->backlight.level = intel_panel_compute_brightness(connector, val);
1227
1228         panel->backlight.enabled = (pch_ctl1 & BLM_PCH_PWM_ENABLE) &&
1229                 panel->backlight.level != 0;
1230
1231         return 0;
1232 }
1233
1234 static int pch_setup_backlight(struct intel_connector *connector, enum pipe unused)
1235 {
1236         struct drm_device *dev = connector->base.dev;
1237         struct drm_i915_private *dev_priv = dev->dev_private;
1238         struct intel_panel *panel = &connector->panel;
1239         u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
1240
1241         pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
1242         panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1243
1244         pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2);
1245         panel->backlight.max = pch_ctl2 >> 16;
1246         if (!panel->backlight.max)
1247                 return -ENODEV;
1248
1249         panel->backlight.min = get_backlight_min_vbt(connector);
1250
1251         val = pch_get_backlight(connector);
1252         panel->backlight.level = intel_panel_compute_brightness(connector, val);
1253
1254         cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
1255         panel->backlight.enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
1256                 (pch_ctl1 & BLM_PCH_PWM_ENABLE) && panel->backlight.level != 0;
1257
1258         return 0;
1259 }
1260
1261 static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unused)
1262 {
1263         struct drm_device *dev = connector->base.dev;
1264         struct drm_i915_private *dev_priv = dev->dev_private;
1265         struct intel_panel *panel = &connector->panel;
1266         u32 ctl, val;
1267
1268         ctl = I915_READ(BLC_PWM_CTL);
1269
1270         if (IS_GEN2(dev) || IS_I915GM(dev) || IS_I945GM(dev))
1271                 panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
1272
1273         if (IS_PINEVIEW(dev))
1274                 panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
1275
1276         panel->backlight.max = ctl >> 17;
1277         if (panel->backlight.combination_mode)
1278                 panel->backlight.max *= 0xff;
1279
1280         if (!panel->backlight.max)
1281                 return -ENODEV;
1282
1283         panel->backlight.min = get_backlight_min_vbt(connector);
1284
1285         val = i9xx_get_backlight(connector);
1286         panel->backlight.level = intel_panel_compute_brightness(connector, val);
1287
1288         panel->backlight.enabled = panel->backlight.level != 0;
1289
1290         return 0;
1291 }
1292
1293 static int i965_setup_backlight(struct intel_connector *connector, enum pipe unused)
1294 {
1295         struct drm_device *dev = connector->base.dev;
1296         struct drm_i915_private *dev_priv = dev->dev_private;
1297         struct intel_panel *panel = &connector->panel;
1298         u32 ctl, ctl2, val;
1299
1300         ctl2 = I915_READ(BLC_PWM_CTL2);
1301         panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
1302         panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1303
1304         ctl = I915_READ(BLC_PWM_CTL);
1305         panel->backlight.max = ctl >> 16;
1306         if (panel->backlight.combination_mode)
1307                 panel->backlight.max *= 0xff;
1308
1309         if (!panel->backlight.max)
1310                 return -ENODEV;
1311
1312         panel->backlight.min = get_backlight_min_vbt(connector);
1313
1314         val = i9xx_get_backlight(connector);
1315         panel->backlight.level = intel_panel_compute_brightness(connector, val);
1316
1317         panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
1318                 panel->backlight.level != 0;
1319
1320         return 0;
1321 }
1322
1323 static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe)
1324 {
1325         struct drm_device *dev = connector->base.dev;
1326         struct drm_i915_private *dev_priv = dev->dev_private;
1327         struct intel_panel *panel = &connector->panel;
1328         enum pipe p;
1329         u32 ctl, ctl2, val;
1330
1331         for_each_pipe(dev_priv, p) {
1332                 u32 cur_val = I915_READ(VLV_BLC_PWM_CTL(p));
1333
1334                 /* Skip if the modulation freq is already set */
1335                 if (cur_val & ~BACKLIGHT_DUTY_CYCLE_MASK)
1336                         continue;
1337
1338                 cur_val &= BACKLIGHT_DUTY_CYCLE_MASK;
1339                 I915_WRITE(VLV_BLC_PWM_CTL(p), (0xf42 << 16) |
1340                            cur_val);
1341         }
1342
1343         if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
1344                 return -ENODEV;
1345
1346         ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
1347         panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1348
1349         ctl = I915_READ(VLV_BLC_PWM_CTL(pipe));
1350         panel->backlight.max = ctl >> 16;
1351         if (!panel->backlight.max)
1352                 return -ENODEV;
1353
1354         panel->backlight.min = get_backlight_min_vbt(connector);
1355
1356         val = _vlv_get_backlight(dev, pipe);
1357         panel->backlight.level = intel_panel_compute_brightness(connector, val);
1358
1359         panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
1360                 panel->backlight.level != 0;
1361
1362         return 0;
1363 }
1364
1365 static int
1366 bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
1367 {
1368         struct drm_device *dev = connector->base.dev;
1369         struct drm_i915_private *dev_priv = dev->dev_private;
1370         struct intel_panel *panel = &connector->panel;
1371         u32 pwm_ctl, val;
1372
1373         pwm_ctl = I915_READ(BXT_BLC_PWM_CTL1);
1374         panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
1375
1376         panel->backlight.max = I915_READ(BXT_BLC_PWM_FREQ1);
1377         if (!panel->backlight.max)
1378                 return -ENODEV;
1379
1380         val = bxt_get_backlight(connector);
1381         panel->backlight.level = intel_panel_compute_brightness(connector, val);
1382
1383         panel->backlight.enabled = (pwm_ctl & BXT_BLC_PWM_ENABLE) &&
1384                 panel->backlight.level != 0;
1385
1386         return 0;
1387 }
1388
1389 int intel_panel_setup_backlight(struct drm_connector *connector, enum pipe pipe)
1390 {
1391         struct drm_device *dev = connector->dev;
1392         struct drm_i915_private *dev_priv = dev->dev_private;
1393         struct intel_connector *intel_connector = to_intel_connector(connector);
1394         struct intel_panel *panel = &intel_connector->panel;
1395         int ret;
1396
1397         if (!dev_priv->vbt.backlight.present) {
1398                 if (dev_priv->quirks & QUIRK_BACKLIGHT_PRESENT) {
1399                         DRM_DEBUG_KMS("no backlight present per VBT, but present per quirk\n");
1400                 } else {
1401                         DRM_DEBUG_KMS("no backlight present per VBT\n");
1402                         return 0;
1403                 }
1404         }
1405
1406         /* set level and max in panel struct */
1407         mutex_lock(&dev_priv->backlight_lock);
1408         ret = dev_priv->display.setup_backlight(intel_connector, pipe);
1409         mutex_unlock(&dev_priv->backlight_lock);
1410
1411         if (ret) {
1412                 DRM_DEBUG_KMS("failed to setup backlight for connector %s\n",
1413                               connector->name);
1414                 return ret;
1415         }
1416
1417         panel->backlight.present = true;
1418
1419         DRM_DEBUG_KMS("Connector %s backlight initialized, %s, brightness %u/%u\n",
1420                       connector->name,
1421                       panel->backlight.enabled ? "enabled" : "disabled",
1422                       panel->backlight.level, panel->backlight.max);
1423
1424         return 0;
1425 }
1426
1427 void intel_panel_destroy_backlight(struct drm_connector *connector)
1428 {
1429         struct intel_connector *intel_connector = to_intel_connector(connector);
1430         struct intel_panel *panel = &intel_connector->panel;
1431
1432         panel->backlight.present = false;
1433 }
1434
1435 /* Set up chip specific backlight functions */
1436 void intel_panel_init_backlight_funcs(struct drm_device *dev)
1437 {
1438         struct drm_i915_private *dev_priv = dev->dev_private;
1439
1440         if (IS_BROXTON(dev)) {
1441                 dev_priv->display.setup_backlight = bxt_setup_backlight;
1442                 dev_priv->display.enable_backlight = bxt_enable_backlight;
1443                 dev_priv->display.disable_backlight = bxt_disable_backlight;
1444                 dev_priv->display.set_backlight = bxt_set_backlight;
1445                 dev_priv->display.get_backlight = bxt_get_backlight;
1446         } else if (IS_BROADWELL(dev) || IS_SKYLAKE(dev)) {
1447                 dev_priv->display.setup_backlight = bdw_setup_backlight;
1448                 dev_priv->display.enable_backlight = bdw_enable_backlight;
1449                 dev_priv->display.disable_backlight = pch_disable_backlight;
1450                 dev_priv->display.set_backlight = bdw_set_backlight;
1451                 dev_priv->display.get_backlight = bdw_get_backlight;
1452         } else if (HAS_PCH_SPLIT(dev)) {
1453                 dev_priv->display.setup_backlight = pch_setup_backlight;
1454                 dev_priv->display.enable_backlight = pch_enable_backlight;
1455                 dev_priv->display.disable_backlight = pch_disable_backlight;
1456                 dev_priv->display.set_backlight = pch_set_backlight;
1457                 dev_priv->display.get_backlight = pch_get_backlight;
1458         } else if (IS_VALLEYVIEW(dev)) {
1459                 dev_priv->display.setup_backlight = vlv_setup_backlight;
1460                 dev_priv->display.enable_backlight = vlv_enable_backlight;
1461                 dev_priv->display.disable_backlight = vlv_disable_backlight;
1462                 dev_priv->display.set_backlight = vlv_set_backlight;
1463                 dev_priv->display.get_backlight = vlv_get_backlight;
1464         } else if (IS_GEN4(dev)) {
1465                 dev_priv->display.setup_backlight = i965_setup_backlight;
1466                 dev_priv->display.enable_backlight = i965_enable_backlight;
1467                 dev_priv->display.disable_backlight = i965_disable_backlight;
1468                 dev_priv->display.set_backlight = i9xx_set_backlight;
1469                 dev_priv->display.get_backlight = i9xx_get_backlight;
1470         } else {
1471                 dev_priv->display.setup_backlight = i9xx_setup_backlight;
1472                 dev_priv->display.enable_backlight = i9xx_enable_backlight;
1473                 dev_priv->display.disable_backlight = i9xx_disable_backlight;
1474                 dev_priv->display.set_backlight = i9xx_set_backlight;
1475                 dev_priv->display.get_backlight = i9xx_get_backlight;
1476         }
1477 }
1478
1479 int intel_panel_init(struct intel_panel *panel,
1480                      struct drm_display_mode *fixed_mode,
1481                      struct drm_display_mode *downclock_mode)
1482 {
1483         panel->fixed_mode = fixed_mode;
1484         panel->downclock_mode = downclock_mode;
1485
1486         return 0;
1487 }
1488
1489 void intel_panel_fini(struct intel_panel *panel)
1490 {
1491         struct intel_connector *intel_connector =
1492                 container_of(panel, struct intel_connector, panel);
1493
1494         if (panel->fixed_mode)
1495                 drm_mode_destroy(intel_connector->base.dev, panel->fixed_mode);
1496
1497         if (panel->downclock_mode)
1498                 drm_mode_destroy(intel_connector->base.dev,
1499                                 panel->downclock_mode);
1500 }
1501
1502 void intel_backlight_register(struct drm_device *dev)
1503 {
1504         struct intel_connector *connector;
1505
1506         list_for_each_entry(connector, &dev->mode_config.connector_list, base.head)
1507                 intel_backlight_device_register(connector);
1508 }
1509
1510 void intel_backlight_unregister(struct drm_device *dev)
1511 {
1512         struct intel_connector *connector;
1513
1514         list_for_each_entry(connector, &dev->mode_config.connector_list, base.head)
1515                 intel_backlight_device_unregister(connector);
1516 }