drivers/gpu/drm/i915/display/intel_backlight.c

   1 // SPDX-License-Identifier: MIT
   2 /*
   3  * Copyright © 2021 Intel Corporation
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/pwm.h>
   8 #include <linux/string_helpers.h>
   9
  10 #include "intel_backlight.h"
  11 #include "intel_connector.h"
  12 #include "intel_de.h"
  13 #include "intel_display_types.h"
  14 #include "intel_dp_aux_backlight.h"
  15 #include "intel_dsi_dcs_backlight.h"
  16 #include "intel_panel.h"
  17 #include "intel_pci_config.h"
  18
  19 /**
  20  * scale - scale values from one range to another
  21  * @source_val: value in range [@source_min..@source_max]
  22  * @source_min: minimum legal value for @source_val
  23  * @source_max: maximum legal value for @source_val
  24  * @target_min: corresponding target value for @source_min
  25  * @target_max: corresponding target value for @source_max
  26  *
  27  * Return @source_val in range [@source_min..@source_max] scaled to range
  28  * [@target_min..@target_max].
  29  */
  30 static u32 scale(u32 source_val,
  31                  u32 source_min, u32 source_max,
  32                  u32 target_min, u32 target_max)
  33 {
  34         u64 target_val;
  35
  36         WARN_ON(source_min > source_max);
  37         WARN_ON(target_min > target_max);
  38
  39         /* defensive */
  40         source_val = clamp(source_val, source_min, source_max);
  41
  42         /* avoid overflows */
  43         target_val = mul_u32_u32(source_val - source_min,
  44                                  target_max - target_min);
  45         target_val = DIV_ROUND_CLOSEST_ULL(target_val, source_max - source_min);
  46         target_val += target_min;
  47
  48         return target_val;
  49 }
  50
  51 /*
  52  * Scale user_level in range [0..user_max] to [0..hw_max], clamping the result
  53  * to [hw_min..hw_max].
  54  */
  55 static u32 clamp_user_to_hw(struct intel_connector *connector,
  56                             u32 user_level, u32 user_max)
  57 {
  58         struct intel_panel *panel = &connector->panel;
  59         u32 hw_level;
  60
  61         hw_level = scale(user_level, 0, user_max, 0, panel->backlight.max);
  62         hw_level = clamp(hw_level, panel->backlight.min, panel->backlight.max);
  63
  64         return hw_level;
  65 }
  66
  67 /* Scale hw_level in range [hw_min..hw_max] to [0..user_max]. */
  68 static u32 scale_hw_to_user(struct intel_connector *connector,
  69                             u32 hw_level, u32 user_max)
  70 {
  71         struct intel_panel *panel = &connector->panel;
  72
  73         return scale(hw_level, panel->backlight.min, panel->backlight.max,
  74                      0, user_max);
  75 }
  76
  77 u32 intel_backlight_invert_pwm_level(struct intel_connector *connector, u32 val)
  78 {
  79         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
  80         struct intel_panel *panel = &connector->panel;
  81
  82         drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
  83
  84         if (dev_priv->params.invert_brightness < 0)
  85                 return val;
  86
  87         if (dev_priv->params.invert_brightness > 0 ||
  88             dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
  89                 return panel->backlight.pwm_level_max - val + panel->backlight.pwm_level_min;
  90         }
  91
  92         return val;
  93 }
  94
  95 void intel_backlight_set_pwm_level(const struct drm_connector_state *conn_state, u32 val)
  96 {
  97         struct intel_connector *connector = to_intel_connector(conn_state->connector);
  98         struct drm_i915_private *i915 = to_i915(connector->base.dev);
  99         struct intel_panel *panel = &connector->panel;
 100
 101         drm_dbg_kms(&i915->drm, "set backlight PWM = %d\n", val);
 102         panel->backlight.pwm_funcs->set(conn_state, val);
 103 }
 104
 105 u32 intel_backlight_level_to_pwm(struct intel_connector *connector, u32 val)
 106 {
 107         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 108         struct intel_panel *panel = &connector->panel;
 109
 110         drm_WARN_ON_ONCE(&dev_priv->drm,
 111                          panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
 112
 113         val = scale(val, panel->backlight.min, panel->backlight.max,
 114                     panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
 115
 116         return intel_backlight_invert_pwm_level(connector, val);
 117 }
 118
 119 u32 intel_backlight_level_from_pwm(struct intel_connector *connector, u32 val)
 120 {
 121         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 122         struct intel_panel *panel = &connector->panel;
 123
 124         drm_WARN_ON_ONCE(&dev_priv->drm,
 125                          panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
 126
 127         if (dev_priv->params.invert_brightness > 0 ||
 128             (dev_priv->params.invert_brightness == 0 && dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS))
 129                 val = panel->backlight.pwm_level_max - (val - panel->backlight.pwm_level_min);
 130
 131         return scale(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max,
 132                      panel->backlight.min, panel->backlight.max);
 133 }
 134
 135 static u32 lpt_get_backlight(struct intel_connector *connector, enum pipe unused)
 136 {
 137         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 138
 139         return intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
 140 }
 141
 142 static u32 pch_get_backlight(struct intel_connector *connector, enum pipe unused)
 143 {
 144         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 145
 146         return intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
 147 }
 148
 149 static u32 i9xx_get_backlight(struct intel_connector *connector, enum pipe unused)
 150 {
 151         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 152         struct intel_panel *panel = &connector->panel;
 153         u32 val;
 154
 155         val = intel_de_read(dev_priv, BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
 156         if (DISPLAY_VER(dev_priv) < 4)
 157                 val >>= 1;
 158
 159         if (panel->backlight.combination_mode) {
 160                 u8 lbpc;
 161
 162                 pci_read_config_byte(to_pci_dev(dev_priv->drm.dev), LBPC, &lbpc);
 163                 val *= lbpc;
 164         }
 165
 166         return val;
 167 }
 168
 169 static u32 vlv_get_backlight(struct intel_connector *connector, enum pipe pipe)
 170 {
 171         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 172
 173         if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
 174                 return 0;
 175
 176         return intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
 177 }
 178
 179 static u32 bxt_get_backlight(struct intel_connector *connector, enum pipe unused)
 180 {
 181         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 182         struct intel_panel *panel = &connector->panel;
 183
 184         return intel_de_read(dev_priv,
 185                              BXT_BLC_PWM_DUTY(panel->backlight.controller));
 186 }
 187
 188 static u32 ext_pwm_get_backlight(struct intel_connector *connector, enum pipe unused)
 189 {
 190         struct intel_panel *panel = &connector->panel;
 191         struct pwm_state state;
 192
 193         pwm_get_state(panel->backlight.pwm, &state);
 194         return pwm_get_relative_duty_cycle(&state, 100);
 195 }
 196
 197 static void lpt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 198 {
 199         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 200         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 201
 202         u32 val = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 203         intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, val | level);
 204 }
 205
 206 static void pch_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 207 {
 208         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 209         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 210         u32 tmp;
 211
 212         tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 213         intel_de_write(dev_priv, BLC_PWM_CPU_CTL, tmp | level);
 214 }
 215
 216 static void i9xx_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 217 {
 218         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 219         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 220         struct intel_panel *panel = &connector->panel;
 221         u32 tmp, mask;
 222
 223         drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
 224
 225         if (panel->backlight.combination_mode) {
 226                 u8 lbpc;
 227
 228                 lbpc = level * 0xfe / panel->backlight.pwm_level_max + 1;
 229                 level /= lbpc;
 230                 pci_write_config_byte(to_pci_dev(dev_priv->drm.dev), LBPC, lbpc);
 231         }
 232
 233         if (DISPLAY_VER(dev_priv) == 4) {
 234                 mask = BACKLIGHT_DUTY_CYCLE_MASK;
 235         } else {
 236                 level <<= 1;
 237                 mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV;
 238         }
 239
 240         tmp = intel_de_read(dev_priv, BLC_PWM_CTL) & ~mask;
 241         intel_de_write(dev_priv, BLC_PWM_CTL, tmp | level);
 242 }
 243
 244 static void vlv_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 245 {
 246         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 247         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 248         enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
 249         u32 tmp;
 250
 251         tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 252         intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), tmp | level);
 253 }
 254
 255 static void bxt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 256 {
 257         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 258         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 259         struct intel_panel *panel = &connector->panel;
 260
 261         intel_de_write(dev_priv,
 262                        BXT_BLC_PWM_DUTY(panel->backlight.controller), level);
 263 }
 264
 265 static void ext_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 266 {
 267         struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
 268
 269         pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
 270         pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
 271 }
 272
 273 static void
 274 intel_panel_actually_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 275 {
 276         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 277         struct drm_i915_private *i915 = to_i915(connector->base.dev);
 278         struct intel_panel *panel = &connector->panel;
 279
 280         drm_dbg_kms(&i915->drm, "set backlight level = %d\n", level);
 281
 282         panel->backlight.funcs->set(conn_state, level);
 283 }
 284
 285 /* set backlight brightness to level in range [0..max], assuming hw min is
 286  * respected.
 287  */
 288 void intel_backlight_set_acpi(const struct drm_connector_state *conn_state,
 289                               u32 user_level, u32 user_max)
 290 {
 291         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 292         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 293         struct intel_panel *panel = &connector->panel;
 294         u32 hw_level;
 295
 296         /*
 297          * Lack of crtc may occur during driver init because
 298          * connection_mutex isn't held across the entire backlight
 299          * setup + modeset readout, and the BIOS can issue the
 300          * requests at any time.
 301          */
 302         if (!panel->backlight.present || !conn_state->crtc)
 303                 return;
 304
 305         mutex_lock(&dev_priv->backlight_lock);
 306
 307         drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
 308
 309         hw_level = clamp_user_to_hw(connector, user_level, user_max);
 310         panel->backlight.level = hw_level;
 311
 312         if (panel->backlight.device)
 313                 panel->backlight.device->props.brightness =
 314                         scale_hw_to_user(connector,
 315                                          panel->backlight.level,
 316                                          panel->backlight.device->props.max_brightness);
 317
 318         if (panel->backlight.enabled)
 319                 intel_panel_actually_set_backlight(conn_state, hw_level);
 320
 321         mutex_unlock(&dev_priv->backlight_lock);
 322 }
 323
 324 static void lpt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
 325 {
 326         struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 327         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 328         u32 tmp;
 329
 330         intel_backlight_set_pwm_level(old_conn_state, level);
 331
 332         /*
 333          * Although we don't support or enable CPU PWM with LPT/SPT based
 334          * systems, it may have been enabled prior to loading the
 335          * driver. Disable to avoid warnings on LCPLL disable.
 336          *
 337          * This needs rework if we need to add support for CPU PWM on PCH split
 338          * platforms.
 339          */
 340         tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
 341         if (tmp & BLM_PWM_ENABLE) {
 342                 drm_dbg_kms(&dev_priv->drm,
 343                             "cpu backlight was enabled, disabling\n");
 344                 intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
 345                                tmp & ~BLM_PWM_ENABLE);
 346         }
 347
 348         tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
 349         intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
 350 }
 351
 352 static void pch_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
 353 {
 354         struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 355         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 356         u32 tmp;
 357
 358         intel_backlight_set_pwm_level(old_conn_state, val);
 359
 360         tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
 361         intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
 362
 363         tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
 364         intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
 365 }
 366
 367 static void i9xx_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
 368 {
 369         intel_backlight_set_pwm_level(old_conn_state, val);
 370 }
 371
 372 static void i965_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
 373 {
 374         struct drm_i915_private *dev_priv = to_i915(old_conn_state->connector->dev);
 375         u32 tmp;
 376
 377         intel_backlight_set_pwm_level(old_conn_state, val);
 378
 379         tmp = intel_de_read(dev_priv, BLC_PWM_CTL2);
 380         intel_de_write(dev_priv, BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
 381 }
 382
 383 static void vlv_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
 384 {
 385         struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 386         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 387         enum pipe pipe = to_intel_crtc(old_conn_state->crtc)->pipe;
 388         u32 tmp;
 389
 390         intel_backlight_set_pwm_level(old_conn_state, val);
 391
 392         tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
 393         intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
 394                        tmp & ~BLM_PWM_ENABLE);
 395 }
 396
 397 static void bxt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
 398 {
 399         struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 400         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 401         struct intel_panel *panel = &connector->panel;
 402         u32 tmp;
 403
 404         intel_backlight_set_pwm_level(old_conn_state, val);
 405
 406         tmp = intel_de_read(dev_priv,
 407                             BXT_BLC_PWM_CTL(panel->backlight.controller));
 408         intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
 409                        tmp & ~BXT_BLC_PWM_ENABLE);
 410
 411         if (panel->backlight.controller == 1) {
 412                 val = intel_de_read(dev_priv, UTIL_PIN_CTL);
 413                 val &= ~UTIL_PIN_ENABLE;
 414                 intel_de_write(dev_priv, UTIL_PIN_CTL, val);
 415         }
 416 }
 417
 418 static void cnp_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
 419 {
 420         struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 421         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 422         struct intel_panel *panel = &connector->panel;
 423         u32 tmp;
 424
 425         intel_backlight_set_pwm_level(old_conn_state, val);
 426
 427         tmp = intel_de_read(dev_priv,
 428                             BXT_BLC_PWM_CTL(panel->backlight.controller));
 429         intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
 430                        tmp & ~BXT_BLC_PWM_ENABLE);
 431 }
 432
 433 static void ext_pwm_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
 434 {
 435         struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 436         struct intel_panel *panel = &connector->panel;
 437
 438         intel_backlight_set_pwm_level(old_conn_state, level);
 439
 440         panel->backlight.pwm_state.enabled = false;
 441         pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
 442 }
 443
 444 void intel_backlight_disable(const struct drm_connector_state *old_conn_state)
 445 {
 446         struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 447         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 448         struct intel_panel *panel = &connector->panel;
 449
 450         if (!panel->backlight.present)
 451                 return;
 452
 453         /*
 454          * Do not disable backlight on the vga_switcheroo path. When switching
 455          * away from i915, the other client may depend on i915 to handle the
 456          * backlight. This will leave the backlight on unnecessarily when
 457          * another client is not activated.
 458          */
 459         if (dev_priv->drm.switch_power_state == DRM_SWITCH_POWER_CHANGING) {
 460                 drm_dbg_kms(&dev_priv->drm,
 461                             "Skipping backlight disable on vga switch\n");
 462                 return;
 463         }
 464
 465         mutex_lock(&dev_priv->backlight_lock);
 466
 467         if (panel->backlight.device)
 468                 panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
 469         panel->backlight.enabled = false;
 470         panel->backlight.funcs->disable(old_conn_state, 0);
 471
 472         mutex_unlock(&dev_priv->backlight_lock);
 473 }
 474
 475 static void lpt_enable_backlight(const struct intel_crtc_state *crtc_state,
 476                                  const struct drm_connector_state *conn_state, u32 level)
 477 {
 478         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 479         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 480         struct intel_panel *panel = &connector->panel;
 481         u32 pch_ctl1, pch_ctl2, schicken;
 482
 483         pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
 484         if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
 485                 drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
 486                 pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
 487                 intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
 488         }
 489
 490         if (HAS_PCH_LPT(dev_priv)) {
 491                 schicken = intel_de_read(dev_priv, SOUTH_CHICKEN2);
 492                 if (panel->backlight.alternate_pwm_increment)
 493                         schicken |= LPT_PWM_GRANULARITY;
 494                 else
 495                         schicken &= ~LPT_PWM_GRANULARITY;
 496                 intel_de_write(dev_priv, SOUTH_CHICKEN2, schicken);
 497         } else {
 498                 schicken = intel_de_read(dev_priv, SOUTH_CHICKEN1);
 499                 if (panel->backlight.alternate_pwm_increment)
 500                         schicken |= SPT_PWM_GRANULARITY;
 501                 else
 502                         schicken &= ~SPT_PWM_GRANULARITY;
 503                 intel_de_write(dev_priv, SOUTH_CHICKEN1, schicken);
 504         }
 505
 506         pch_ctl2 = panel->backlight.pwm_level_max << 16;
 507         intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
 508
 509         pch_ctl1 = 0;
 510         if (panel->backlight.active_low_pwm)
 511                 pch_ctl1 |= BLM_PCH_POLARITY;
 512
 513         /* After LPT, override is the default. */
 514         if (HAS_PCH_LPT(dev_priv))
 515                 pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
 516
 517         intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
 518         intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
 519         intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
 520                        pch_ctl1 | BLM_PCH_PWM_ENABLE);
 521
 522         /* This won't stick until the above enable. */
 523         intel_backlight_set_pwm_level(conn_state, level);
 524 }
 525
 526 static void pch_enable_backlight(const struct intel_crtc_state *crtc_state,
 527                                  const struct drm_connector_state *conn_state, u32 level)
 528 {
 529         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 530         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 531         struct intel_panel *panel = &connector->panel;
 532         enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
 533         u32 cpu_ctl2, pch_ctl1, pch_ctl2;
 534
 535         cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
 536         if (cpu_ctl2 & BLM_PWM_ENABLE) {
 537                 drm_dbg_kms(&dev_priv->drm, "cpu backlight already enabled\n");
 538                 cpu_ctl2 &= ~BLM_PWM_ENABLE;
 539                 intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
 540         }
 541
 542         pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
 543         if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
 544                 drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
 545                 pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
 546                 intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
 547         }
 548
 549         if (cpu_transcoder == TRANSCODER_EDP)
 550                 cpu_ctl2 = BLM_TRANSCODER_EDP;
 551         else
 552                 cpu_ctl2 = BLM_PIPE(cpu_transcoder);
 553         intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
 554         intel_de_posting_read(dev_priv, BLC_PWM_CPU_CTL2);
 555         intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
 556
 557         /* This won't stick until the above enable. */
 558         intel_backlight_set_pwm_level(conn_state, level);
 559
 560         pch_ctl2 = panel->backlight.pwm_level_max << 16;
 561         intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
 562
 563         pch_ctl1 = 0;
 564         if (panel->backlight.active_low_pwm)
 565                 pch_ctl1 |= BLM_PCH_POLARITY;
 566
 567         intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
 568         intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
 569         intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
 570                        pch_ctl1 | BLM_PCH_PWM_ENABLE);
 571 }
 572
 573 static void i9xx_enable_backlight(const struct intel_crtc_state *crtc_state,
 574                                   const struct drm_connector_state *conn_state, u32 level)
 575 {
 576         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 577         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 578         struct intel_panel *panel = &connector->panel;
 579         u32 ctl, freq;
 580
 581         ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
 582         if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
 583                 drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
 584                 intel_de_write(dev_priv, BLC_PWM_CTL, 0);
 585         }
 586
 587         freq = panel->backlight.pwm_level_max;
 588         if (panel->backlight.combination_mode)
 589                 freq /= 0xff;
 590
 591         ctl = freq << 17;
 592         if (panel->backlight.combination_mode)
 593                 ctl |= BLM_LEGACY_MODE;
 594         if (IS_PINEVIEW(dev_priv) && panel->backlight.active_low_pwm)
 595                 ctl |= BLM_POLARITY_PNV;
 596
 597         intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
 598         intel_de_posting_read(dev_priv, BLC_PWM_CTL);
 599
 600         /* XXX: combine this into above write? */
 601         intel_backlight_set_pwm_level(conn_state, level);
 602
 603         /*
 604          * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is
 605          * 855gm only, but checking for gen2 is safe, as 855gm is the only gen2
 606          * that has backlight.
 607          */
 608         if (DISPLAY_VER(dev_priv) == 2)
 609                 intel_de_write(dev_priv, BLC_HIST_CTL, BLM_HISTOGRAM_ENABLE);
 610 }
 611
 612 static void i965_enable_backlight(const struct intel_crtc_state *crtc_state,
 613                                   const struct drm_connector_state *conn_state, u32 level)
 614 {
 615         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 616         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 617         struct intel_panel *panel = &connector->panel;
 618         enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
 619         u32 ctl, ctl2, freq;
 620
 621         ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
 622         if (ctl2 & BLM_PWM_ENABLE) {
 623                 drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
 624                 ctl2 &= ~BLM_PWM_ENABLE;
 625                 intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
 626         }
 627
 628         freq = panel->backlight.pwm_level_max;
 629         if (panel->backlight.combination_mode)
 630                 freq /= 0xff;
 631
 632         ctl = freq << 16;
 633         intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
 634
 635         ctl2 = BLM_PIPE(pipe);
 636         if (panel->backlight.combination_mode)
 637                 ctl2 |= BLM_COMBINATION_MODE;
 638         if (panel->backlight.active_low_pwm)
 639                 ctl2 |= BLM_POLARITY_I965;
 640         intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
 641         intel_de_posting_read(dev_priv, BLC_PWM_CTL2);
 642         intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
 643
 644         intel_backlight_set_pwm_level(conn_state, level);
 645 }
 646
 647 static void vlv_enable_backlight(const struct intel_crtc_state *crtc_state,
 648                                  const struct drm_connector_state *conn_state, u32 level)
 649 {
 650         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 651         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 652         struct intel_panel *panel = &connector->panel;
 653         enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
 654         u32 ctl, ctl2;
 655
 656         ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
 657         if (ctl2 & BLM_PWM_ENABLE) {
 658                 drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
 659                 ctl2 &= ~BLM_PWM_ENABLE;
 660                 intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
 661         }
 662
 663         ctl = panel->backlight.pwm_level_max << 16;
 664         intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), ctl);
 665
 666         /* XXX: combine this into above write? */
 667         intel_backlight_set_pwm_level(conn_state, level);
 668
 669         ctl2 = 0;
 670         if (panel->backlight.active_low_pwm)
 671                 ctl2 |= BLM_POLARITY_I965;
 672         intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
 673         intel_de_posting_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
 674         intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
 675                        ctl2 | BLM_PWM_ENABLE);
 676 }
 677
 678 static void bxt_enable_backlight(const struct intel_crtc_state *crtc_state,
 679                                  const struct drm_connector_state *conn_state, u32 level)
 680 {
 681         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 682         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 683         struct intel_panel *panel = &connector->panel;
 684         enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
 685         u32 pwm_ctl, val;
 686
 687         /* Controller 1 uses the utility pin. */
 688         if (panel->backlight.controller == 1) {
 689                 val = intel_de_read(dev_priv, UTIL_PIN_CTL);
 690                 if (val & UTIL_PIN_ENABLE) {
 691                         drm_dbg_kms(&dev_priv->drm,
 692                                     "util pin already enabled\n");
 693                         val &= ~UTIL_PIN_ENABLE;
 694                         intel_de_write(dev_priv, UTIL_PIN_CTL, val);
 695                 }
 696
 697                 val = 0;
 698                 if (panel->backlight.util_pin_active_low)
 699                         val |= UTIL_PIN_POLARITY;
 700                 intel_de_write(dev_priv, UTIL_PIN_CTL,
 701                                val | UTIL_PIN_PIPE(pipe) | UTIL_PIN_MODE_PWM | UTIL_PIN_ENABLE);
 702         }
 703
 704         pwm_ctl = intel_de_read(dev_priv,
 705                                 BXT_BLC_PWM_CTL(panel->backlight.controller));
 706         if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
 707                 drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
 708                 pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
 709                 intel_de_write(dev_priv,
 710                                BXT_BLC_PWM_CTL(panel->backlight.controller),
 711                                pwm_ctl);
 712         }
 713
 714         intel_de_write(dev_priv,
 715                        BXT_BLC_PWM_FREQ(panel->backlight.controller),
 716                        panel->backlight.pwm_level_max);
 717
 718         intel_backlight_set_pwm_level(conn_state, level);
 719
 720         pwm_ctl = 0;
 721         if (panel->backlight.active_low_pwm)
 722                 pwm_ctl |= BXT_BLC_PWM_POLARITY;
 723
 724         intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
 725                        pwm_ctl);
 726         intel_de_posting_read(dev_priv,
 727                               BXT_BLC_PWM_CTL(panel->backlight.controller));
 728         intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
 729                        pwm_ctl | BXT_BLC_PWM_ENABLE);
 730 }
 731
 732 static void cnp_enable_backlight(const struct intel_crtc_state *crtc_state,
 733                                  const struct drm_connector_state *conn_state, u32 level)
 734 {
 735         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 736         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 737         struct intel_panel *panel = &connector->panel;
 738         u32 pwm_ctl;
 739
 740         pwm_ctl = intel_de_read(dev_priv,
 741                                 BXT_BLC_PWM_CTL(panel->backlight.controller));
 742         if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
 743                 drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
 744                 pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
 745                 intel_de_write(dev_priv,
 746                                BXT_BLC_PWM_CTL(panel->backlight.controller),
 747                                pwm_ctl);
 748         }
 749
 750         intel_de_write(dev_priv,
 751                        BXT_BLC_PWM_FREQ(panel->backlight.controller),
 752                        panel->backlight.pwm_level_max);
 753
 754         intel_backlight_set_pwm_level(conn_state, level);
 755
 756         pwm_ctl = 0;
 757         if (panel->backlight.active_low_pwm)
 758                 pwm_ctl |= BXT_BLC_PWM_POLARITY;
 759
 760         intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
 761                        pwm_ctl);
 762         intel_de_posting_read(dev_priv,
 763                               BXT_BLC_PWM_CTL(panel->backlight.controller));
 764         intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
 765                        pwm_ctl | BXT_BLC_PWM_ENABLE);
 766 }
 767
 768 static void ext_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
 769                                      const struct drm_connector_state *conn_state, u32 level)
 770 {
 771         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 772         struct intel_panel *panel = &connector->panel;
 773
 774         pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
 775         panel->backlight.pwm_state.enabled = true;
 776         pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
 777 }
 778
 779 static void __intel_backlight_enable(const struct intel_crtc_state *crtc_state,
 780                                      const struct drm_connector_state *conn_state)
 781 {
 782         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 783         struct intel_panel *panel = &connector->panel;
 784
 785         WARN_ON(panel->backlight.max == 0);
 786
 787         if (panel->backlight.level <= panel->backlight.min) {
 788                 panel->backlight.level = panel->backlight.max;
 789                 if (panel->backlight.device)
 790                         panel->backlight.device->props.brightness =
 791                                 scale_hw_to_user(connector,
 792                                                  panel->backlight.level,
 793                                                  panel->backlight.device->props.max_brightness);
 794         }
 795
 796         panel->backlight.funcs->enable(crtc_state, conn_state, panel->backlight.level);
 797         panel->backlight.enabled = true;
 798         if (panel->backlight.device)
 799                 panel->backlight.device->props.power = FB_BLANK_UNBLANK;
 800 }
 801
 802 void intel_backlight_enable(const struct intel_crtc_state *crtc_state,
 803                             const struct drm_connector_state *conn_state)
 804 {
 805         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 806         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 807         struct intel_panel *panel = &connector->panel;
 808         enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
 809
 810         if (!panel->backlight.present)
 811                 return;
 812
 813         drm_dbg_kms(&dev_priv->drm, "pipe %c\n", pipe_name(pipe));
 814
 815         mutex_lock(&dev_priv->backlight_lock);
 816
 817         __intel_backlight_enable(crtc_state, conn_state);
 818
 819         mutex_unlock(&dev_priv->backlight_lock);
 820 }
 821
 822 #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
 823 static u32 intel_panel_get_backlight(struct intel_connector *connector)
 824 {
 825         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 826         struct intel_panel *panel = &connector->panel;
 827         u32 val = 0;
 828
 829         mutex_lock(&dev_priv->backlight_lock);
 830
 831         if (panel->backlight.enabled)
 832                 val = panel->backlight.funcs->get(connector, intel_connector_get_pipe(connector));
 833
 834         mutex_unlock(&dev_priv->backlight_lock);
 835
 836         drm_dbg_kms(&dev_priv->drm, "get backlight PWM = %d\n", val);
 837         return val;
 838 }
 839
 840 /* Scale user_level in range [0..user_max] to [hw_min..hw_max]. */
 841 static u32 scale_user_to_hw(struct intel_connector *connector,
 842                             u32 user_level, u32 user_max)
 843 {
 844         struct intel_panel *panel = &connector->panel;
 845
 846         return scale(user_level, 0, user_max,
 847                      panel->backlight.min, panel->backlight.max);
 848 }
 849
 850 /* set backlight brightness to level in range [0..max], scaling wrt hw min */
 851 static void intel_panel_set_backlight(const struct drm_connector_state *conn_state,
 852                                       u32 user_level, u32 user_max)
 853 {
 854         struct intel_connector *connector = to_intel_connector(conn_state->connector);
 855         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
 856         struct intel_panel *panel = &connector->panel;
 857         u32 hw_level;
 858
 859         if (!panel->backlight.present)
 860                 return;
 861
 862         mutex_lock(&dev_priv->backlight_lock);
 863
 864         drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
 865
 866         hw_level = scale_user_to_hw(connector, user_level, user_max);
 867         panel->backlight.level = hw_level;
 868
 869         if (panel->backlight.enabled)
 870                 intel_panel_actually_set_backlight(conn_state, hw_level);
 871
 872         mutex_unlock(&dev_priv->backlight_lock);
 873 }
 874
 875 static int intel_backlight_device_update_status(struct backlight_device *bd)
 876 {
 877         struct intel_connector *connector = bl_get_data(bd);
 878         struct intel_panel *panel = &connector->panel;
 879         struct drm_device *dev = connector->base.dev;
 880
 881         drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 882         DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
 883                       bd->props.brightness, bd->props.max_brightness);
 884         intel_panel_set_backlight(connector->base.state, bd->props.brightness,
 885                                   bd->props.max_brightness);
 886
 887         /*
 888          * Allow flipping bl_power as a sub-state of enabled. Sadly the
 889          * backlight class device does not make it easy to differentiate
 890          * between callbacks for brightness and bl_power, so our backlight_power
 891          * callback needs to take this into account.
 892          */
 893         if (panel->backlight.enabled) {
 894                 if (panel->backlight.power) {
 895                         bool enable = bd->props.power == FB_BLANK_UNBLANK &&
 896                                 bd->props.brightness != 0;
 897                         panel->backlight.power(connector, enable);
 898                 }
 899         } else {
 900                 bd->props.power = FB_BLANK_POWERDOWN;
 901         }
 902
 903         drm_modeset_unlock(&dev->mode_config.connection_mutex);
 904         return 0;
 905 }
 906
 907 static int intel_backlight_device_get_brightness(struct backlight_device *bd)
 908 {
 909         struct intel_connector *connector = bl_get_data(bd);
 910         struct drm_device *dev = connector->base.dev;
 911         struct drm_i915_private *dev_priv = to_i915(dev);
 912         intel_wakeref_t wakeref;
 913         int ret = 0;
 914
 915         with_intel_runtime_pm(&dev_priv->runtime_pm, wakeref) {
 916                 u32 hw_level;
 917
 918                 drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 919
 920                 hw_level = intel_panel_get_backlight(connector);
 921                 ret = scale_hw_to_user(connector,
 922                                        hw_level, bd->props.max_brightness);
 923
 924                 drm_modeset_unlock(&dev->mode_config.connection_mutex);
 925         }
 926
 927         return ret;
 928 }
 929
 930 static const struct backlight_ops intel_backlight_device_ops = {
 931         .update_status = intel_backlight_device_update_status,
 932         .get_brightness = intel_backlight_device_get_brightness,
 933 };
 934
 935 int intel_backlight_device_register(struct intel_connector *connector)
 936 {
 937         struct drm_i915_private *i915 = to_i915(connector->base.dev);
 938         struct intel_panel *panel = &connector->panel;
 939         struct backlight_properties props;
 940         struct backlight_device *bd;
 941         const char *name;
 942         int ret = 0;
 943
 944         if (WARN_ON(panel->backlight.device))
 945                 return -ENODEV;
 946
 947         if (!panel->backlight.present)
 948                 return 0;
 949
 950         WARN_ON(panel->backlight.max == 0);
 951
 952         memset(&props, 0, sizeof(props));
 953         props.type = BACKLIGHT_RAW;
 954
 955         /*
 956          * Note: Everything should work even if the backlight device max
 957          * presented to the userspace is arbitrarily chosen.
 958          */
 959         props.max_brightness = panel->backlight.max;
 960         props.brightness = scale_hw_to_user(connector,
 961                                             panel->backlight.level,
 962                                             props.max_brightness);
 963
 964         if (panel->backlight.enabled)
 965                 props.power = FB_BLANK_UNBLANK;
 966         else
 967                 props.power = FB_BLANK_POWERDOWN;
 968
 969         name = kstrdup("intel_backlight", GFP_KERNEL);
 970         if (!name)
 971                 return -ENOMEM;
 972
 973         bd = backlight_device_register(name, connector->base.kdev, connector,
 974                                        &intel_backlight_device_ops, &props);
 975
 976         /*
 977          * Using the same name independent of the drm device or connector
 978          * prevents registration of multiple backlight devices in the
 979          * driver. However, we need to use the default name for backward
 980          * compatibility. Use unique names for subsequent backlight devices as a
 981          * fallback when the default name already exists.
 982          */
 983         if (IS_ERR(bd) && PTR_ERR(bd) == -EEXIST) {
 984                 kfree(name);
 985                 name = kasprintf(GFP_KERNEL, "card%d-%s-backlight",
 986                                  i915->drm.primary->index, connector->base.name);
 987                 if (!name)
 988                         return -ENOMEM;
 989
 990                 bd = backlight_device_register(name, connector->base.kdev, connector,
 991                                                &intel_backlight_device_ops, &props);
 992         }
 993
 994         if (IS_ERR(bd)) {
 995                 drm_err(&i915->drm,
 996                         "[CONNECTOR:%d:%s] backlight device %s register failed: %ld\n",
 997                         connector->base.base.id, connector->base.name, name, PTR_ERR(bd));
 998                 ret = PTR_ERR(bd);
 999                 goto out;
1000         }
1001
1002         panel->backlight.device = bd;
1003
1004         drm_dbg_kms(&i915->drm,
1005                     "[CONNECTOR:%d:%s] backlight device %s registered\n",
1006                     connector->base.base.id, connector->base.name, name);
1007
1008 out:
1009         kfree(name);
1010
1011         return ret;
1012 }
1013
1014 void intel_backlight_device_unregister(struct intel_connector *connector)
1015 {
1016         struct intel_panel *panel = &connector->panel;
1017
1018         if (panel->backlight.device) {
1019                 backlight_device_unregister(panel->backlight.device);
1020                 panel->backlight.device = NULL;
1021         }
1022 }
1023 #endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
1024
1025 /*
1026  * CNP: PWM clock frequency is 19.2 MHz or 24 MHz.
1027  *      PWM increment = 1
1028  */
1029 static u32 cnp_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1030 {
1031         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1032
1033         return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
1034                                  pwm_freq_hz);
1035 }
1036
1037 /*
1038  * BXT: PWM clock frequency = 19.2 MHz.
1039  */
1040 static u32 bxt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1041 {
1042         return DIV_ROUND_CLOSEST(KHz(19200), pwm_freq_hz);
1043 }
1044
1045 /*
1046  * SPT: This value represents the period of the PWM stream in clock periods
1047  * multiplied by 16 (default increment) or 128 (alternate increment selected in
1048  * SCHICKEN_1 bit 0). PWM clock is 24 MHz.
1049  */
1050 static u32 spt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1051 {
1052         struct intel_panel *panel = &connector->panel;
1053         u32 mul;
1054
1055         if (panel->backlight.alternate_pwm_increment)
1056                 mul = 128;
1057         else
1058                 mul = 16;
1059
1060         return DIV_ROUND_CLOSEST(MHz(24), pwm_freq_hz * mul);
1061 }
1062
1063 /*
1064  * LPT: This value represents the period of the PWM stream in clock periods
1065  * multiplied by 128 (default increment) or 16 (alternate increment, selected in
1066  * LPT SOUTH_CHICKEN2 register bit 5).
1067  */
1068 static u32 lpt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1069 {
1070         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1071         struct intel_panel *panel = &connector->panel;
1072         u32 mul, clock;
1073
1074         if (panel->backlight.alternate_pwm_increment)
1075                 mul = 16;
1076         else
1077                 mul = 128;
1078
1079         if (HAS_PCH_LPT_H(dev_priv))
1080                 clock = MHz(135); /* LPT:H */
1081         else
1082                 clock = MHz(24); /* LPT:LP */
1083
1084         return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
1085 }
1086
1087 /*
1088  * ILK/SNB/IVB: This value represents the period of the PWM stream in PCH
1089  * display raw clocks multiplied by 128.
1090  */
1091 static u32 pch_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1092 {
1093         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1094
1095         return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
1096                                  pwm_freq_hz * 128);
1097 }
1098
1099 /*
1100  * Gen2: This field determines the number of time base events (display core
1101  * clock frequency/32) in total for a complete cycle of modulated backlight
1102  * control.
1103  *
1104  * Gen3: A time base event equals the display core clock ([DevPNV] HRAW clock)
1105  * divided by 32.
1106  */
1107 static u32 i9xx_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1108 {
1109         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1110         int clock;
1111
1112         if (IS_PINEVIEW(dev_priv))
1113                 clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
1114         else
1115                 clock = KHz(dev_priv->cdclk.hw.cdclk);
1116
1117         return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 32);
1118 }
1119
1120 /*
1121  * Gen4: This value represents the period of the PWM stream in display core
1122  * clocks ([DevCTG] HRAW clocks) multiplied by 128.
1123  *
1124  */
1125 static u32 i965_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1126 {
1127         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1128         int clock;
1129
1130         if (IS_G4X(dev_priv))
1131                 clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
1132         else
1133                 clock = KHz(dev_priv->cdclk.hw.cdclk);
1134
1135         return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 128);
1136 }
1137
1138 /*
1139  * VLV: This value represents the period of the PWM stream in display core
1140  * clocks ([DevCTG] 200MHz HRAW clocks) multiplied by 128 or 25MHz S0IX clocks
1141  * multiplied by 16. CHV uses a 19.2MHz S0IX clock.
1142  */
1143 static u32 vlv_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
1144 {
1145         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1146         int mul, clock;
1147
1148         if ((intel_de_read(dev_priv, CBR1_VLV) & CBR_PWM_CLOCK_MUX_SELECT) == 0) {
1149                 if (IS_CHERRYVIEW(dev_priv))
1150                         clock = KHz(19200);
1151                 else
1152                         clock = MHz(25);
1153                 mul = 16;
1154         } else {
1155                 clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
1156                 mul = 128;
1157         }
1158
1159         return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
1160 }
1161
1162 static u16 get_vbt_pwm_freq(struct drm_i915_private *dev_priv)
1163 {
1164         u16 pwm_freq_hz = dev_priv->vbt.backlight.pwm_freq_hz;
1165
1166         if (pwm_freq_hz) {
1167                 drm_dbg_kms(&dev_priv->drm,
1168                             "VBT defined backlight frequency %u Hz\n",
1169                             pwm_freq_hz);
1170         } else {
1171                 pwm_freq_hz = 200;
1172                 drm_dbg_kms(&dev_priv->drm,
1173                             "default backlight frequency %u Hz\n",
1174                             pwm_freq_hz);
1175         }
1176
1177         return pwm_freq_hz;
1178 }
1179
1180 static u32 get_backlight_max_vbt(struct intel_connector *connector)
1181 {
1182         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1183         struct intel_panel *panel = &connector->panel;
1184         u16 pwm_freq_hz = get_vbt_pwm_freq(dev_priv);
1185         u32 pwm;
1186
1187         if (!panel->backlight.pwm_funcs->hz_to_pwm) {
1188                 drm_dbg_kms(&dev_priv->drm,
1189                             "backlight frequency conversion not supported\n");
1190                 return 0;
1191         }
1192
1193         pwm = panel->backlight.pwm_funcs->hz_to_pwm(connector, pwm_freq_hz);
1194         if (!pwm) {
1195                 drm_dbg_kms(&dev_priv->drm,
1196                             "backlight frequency conversion failed\n");
1197                 return 0;
1198         }
1199
1200         return pwm;
1201 }
1202
1203 /*
1204  * Note: The setup hooks can't assume pipe is set!
1205  */
1206 static u32 get_backlight_min_vbt(struct intel_connector *connector)
1207 {
1208         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1209         struct intel_panel *panel = &connector->panel;
1210         int min;
1211
1212         drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
1213
1214         /*
1215          * XXX: If the vbt value is 255, it makes min equal to max, which leads
1216          * to problems. There are such machines out there. Either our
1217          * interpretation is wrong or the vbt has bogus data. Or both. Safeguard
1218          * against this by letting the minimum be at most (arbitrarily chosen)
1219          * 25% of the max.
1220          */
1221         min = clamp_t(int, dev_priv->vbt.backlight.min_brightness, 0, 64);
1222         if (min != dev_priv->vbt.backlight.min_brightness) {
1223                 drm_dbg_kms(&dev_priv->drm,
1224                             "clamping VBT min backlight %d/255 to %d/255\n",
1225                             dev_priv->vbt.backlight.min_brightness, min);
1226         }
1227
1228         /* vbt value is a coefficient in range [0..255] */
1229         return scale(min, 0, 255, 0, panel->backlight.pwm_level_max);
1230 }
1231
1232 static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unused)
1233 {
1234         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1235         struct intel_panel *panel = &connector->panel;
1236         u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
1237         bool alt, cpu_mode;
1238
1239         if (HAS_PCH_LPT(dev_priv))
1240                 alt = intel_de_read(dev_priv, SOUTH_CHICKEN2) & LPT_PWM_GRANULARITY;
1241         else
1242                 alt = intel_de_read(dev_priv, SOUTH_CHICKEN1) & SPT_PWM_GRANULARITY;
1243         panel->backlight.alternate_pwm_increment = alt;
1244
1245         pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
1246         panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1247
1248         pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
1249         panel->backlight.pwm_level_max = pch_ctl2 >> 16;
1250
1251         cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
1252
1253         if (!panel->backlight.pwm_level_max)
1254                 panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1255
1256         if (!panel->backlight.pwm_level_max)
1257                 return -ENODEV;
1258
1259         panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1260
1261         panel->backlight.pwm_enabled = pch_ctl1 & BLM_PCH_PWM_ENABLE;
1262
1263         cpu_mode = panel->backlight.pwm_enabled && HAS_PCH_LPT(dev_priv) &&
1264                    !(pch_ctl1 & BLM_PCH_OVERRIDE_ENABLE) &&
1265                    (cpu_ctl2 & BLM_PWM_ENABLE);
1266
1267         if (cpu_mode) {
1268                 val = pch_get_backlight(connector, unused);
1269
1270                 drm_dbg_kms(&dev_priv->drm,
1271                             "CPU backlight register was enabled, switching to PCH override\n");
1272
1273                 /* Write converted CPU PWM value to PCH override register */
1274                 lpt_set_backlight(connector->base.state, val);
1275                 intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
1276                                pch_ctl1 | BLM_PCH_OVERRIDE_ENABLE);
1277
1278                 intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
1279                                cpu_ctl2 & ~BLM_PWM_ENABLE);
1280         }
1281
1282         return 0;
1283 }
1284
1285 static int pch_setup_backlight(struct intel_connector *connector, enum pipe unused)
1286 {
1287         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1288         struct intel_panel *panel = &connector->panel;
1289         u32 cpu_ctl2, pch_ctl1, pch_ctl2;
1290
1291         pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
1292         panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
1293
1294         pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
1295         panel->backlight.pwm_level_max = pch_ctl2 >> 16;
1296
1297         if (!panel->backlight.pwm_level_max)
1298                 panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1299
1300         if (!panel->backlight.pwm_level_max)
1301                 return -ENODEV;
1302
1303         panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1304
1305         cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
1306         panel->backlight.pwm_enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
1307                 (pch_ctl1 & BLM_PCH_PWM_ENABLE);
1308
1309         return 0;
1310 }
1311
1312 static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unused)
1313 {
1314         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1315         struct intel_panel *panel = &connector->panel;
1316         u32 ctl, val;
1317
1318         ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
1319
1320         if (DISPLAY_VER(dev_priv) == 2 || IS_I915GM(dev_priv) || IS_I945GM(dev_priv))
1321                 panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
1322
1323         if (IS_PINEVIEW(dev_priv))
1324                 panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
1325
1326         panel->backlight.pwm_level_max = ctl >> 17;
1327
1328         if (!panel->backlight.pwm_level_max) {
1329                 panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1330                 panel->backlight.pwm_level_max >>= 1;
1331         }
1332
1333         if (!panel->backlight.pwm_level_max)
1334                 return -ENODEV;
1335
1336         if (panel->backlight.combination_mode)
1337                 panel->backlight.pwm_level_max *= 0xff;
1338
1339         panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1340
1341         val = i9xx_get_backlight(connector, unused);
1342         val = intel_backlight_invert_pwm_level(connector, val);
1343         val = clamp(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
1344
1345         panel->backlight.pwm_enabled = val != 0;
1346
1347         return 0;
1348 }
1349
1350 static int i965_setup_backlight(struct intel_connector *connector, enum pipe unused)
1351 {
1352         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1353         struct intel_panel *panel = &connector->panel;
1354         u32 ctl, ctl2;
1355
1356         ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
1357         panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
1358         panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1359
1360         ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
1361         panel->backlight.pwm_level_max = ctl >> 16;
1362
1363         if (!panel->backlight.pwm_level_max)
1364                 panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1365
1366         if (!panel->backlight.pwm_level_max)
1367                 return -ENODEV;
1368
1369         if (panel->backlight.combination_mode)
1370                 panel->backlight.pwm_level_max *= 0xff;
1371
1372         panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1373
1374         panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
1375
1376         return 0;
1377 }
1378
1379 static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe)
1380 {
1381         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1382         struct intel_panel *panel = &connector->panel;
1383         u32 ctl, ctl2;
1384
1385         if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
1386                 return -ENODEV;
1387
1388         ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
1389         panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
1390
1391         ctl = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe));
1392         panel->backlight.pwm_level_max = ctl >> 16;
1393
1394         if (!panel->backlight.pwm_level_max)
1395                 panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1396
1397         if (!panel->backlight.pwm_level_max)
1398                 return -ENODEV;
1399
1400         panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1401
1402         panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
1403
1404         return 0;
1405 }
1406
1407 static int
1408 bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
1409 {
1410         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1411         struct intel_panel *panel = &connector->panel;
1412         u32 pwm_ctl, val;
1413
1414         panel->backlight.controller = dev_priv->vbt.backlight.controller;
1415
1416         pwm_ctl = intel_de_read(dev_priv,
1417                                 BXT_BLC_PWM_CTL(panel->backlight.controller));
1418
1419         /* Controller 1 uses the utility pin. */
1420         if (panel->backlight.controller == 1) {
1421                 val = intel_de_read(dev_priv, UTIL_PIN_CTL);
1422                 panel->backlight.util_pin_active_low =
1423                                         val & UTIL_PIN_POLARITY;
1424         }
1425
1426         panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
1427         panel->backlight.pwm_level_max =
1428                 intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
1429
1430         if (!panel->backlight.pwm_level_max)
1431                 panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1432
1433         if (!panel->backlight.pwm_level_max)
1434                 return -ENODEV;
1435
1436         panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1437
1438         panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
1439
1440         return 0;
1441 }
1442
1443 static int
1444 cnp_setup_backlight(struct intel_connector *connector, enum pipe unused)
1445 {
1446         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1447         struct intel_panel *panel = &connector->panel;
1448         u32 pwm_ctl;
1449
1450         /*
1451          * CNP has the BXT implementation of backlight, but with only one
1452          * controller. TODO: ICP has multiple controllers but we only use
1453          * controller 0 for now.
1454          */
1455         panel->backlight.controller = 0;
1456
1457         pwm_ctl = intel_de_read(dev_priv,
1458                                 BXT_BLC_PWM_CTL(panel->backlight.controller));
1459
1460         panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
1461         panel->backlight.pwm_level_max =
1462                 intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
1463
1464         if (!panel->backlight.pwm_level_max)
1465                 panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
1466
1467         if (!panel->backlight.pwm_level_max)
1468                 return -ENODEV;
1469
1470         panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1471
1472         panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
1473
1474         return 0;
1475 }
1476
1477 static int ext_pwm_setup_backlight(struct intel_connector *connector,
1478                                    enum pipe pipe)
1479 {
1480         struct drm_device *dev = connector->base.dev;
1481         struct drm_i915_private *dev_priv = to_i915(dev);
1482         struct intel_panel *panel = &connector->panel;
1483         const char *desc;
1484         u32 level;
1485
1486         /* Get the right PWM chip for DSI backlight according to VBT */
1487         if (dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC) {
1488                 panel->backlight.pwm = pwm_get(dev->dev, "pwm_pmic_backlight");
1489                 desc = "PMIC";
1490         } else {
1491                 panel->backlight.pwm = pwm_get(dev->dev, "pwm_soc_backlight");
1492                 desc = "SoC";
1493         }
1494
1495         if (IS_ERR(panel->backlight.pwm)) {
1496                 drm_err(&dev_priv->drm, "Failed to get the %s PWM chip\n",
1497                         desc);
1498                 panel->backlight.pwm = NULL;
1499                 return -ENODEV;
1500         }
1501
1502         panel->backlight.pwm_level_max = 100; /* 100% */
1503         panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
1504
1505         if (pwm_is_enabled(panel->backlight.pwm)) {
1506                 /* PWM is already enabled, use existing settings */
1507                 pwm_get_state(panel->backlight.pwm, &panel->backlight.pwm_state);
1508
1509                 level = pwm_get_relative_duty_cycle(&panel->backlight.pwm_state,
1510                                                     100);
1511                 level = intel_backlight_invert_pwm_level(connector, level);
1512                 panel->backlight.pwm_enabled = true;
1513
1514                 drm_dbg_kms(&dev_priv->drm, "PWM already enabled at freq %ld, VBT freq %d, level %d\n",
1515                             NSEC_PER_SEC / (unsigned long)panel->backlight.pwm_state.period,
1516                             get_vbt_pwm_freq(dev_priv), level);
1517         } else {
1518                 /* Set period from VBT frequency, leave other settings at 0. */
1519                 panel->backlight.pwm_state.period =
1520                         NSEC_PER_SEC / get_vbt_pwm_freq(dev_priv);
1521         }
1522
1523         drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n",
1524                  desc);
1525         return 0;
1526 }
1527
1528 static void intel_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
1529 {
1530         struct intel_connector *connector = to_intel_connector(conn_state->connector);
1531         struct intel_panel *panel = &connector->panel;
1532
1533         panel->backlight.pwm_funcs->set(conn_state,
1534                                         intel_backlight_invert_pwm_level(connector, level));
1535 }
1536
1537 static u32 intel_pwm_get_backlight(struct intel_connector *connector, enum pipe pipe)
1538 {
1539         struct intel_panel *panel = &connector->panel;
1540
1541         return intel_backlight_invert_pwm_level(connector,
1542                                             panel->backlight.pwm_funcs->get(connector, pipe));
1543 }
1544
1545 static void intel_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
1546                                        const struct drm_connector_state *conn_state, u32 level)
1547 {
1548         struct intel_connector *connector = to_intel_connector(conn_state->connector);
1549         struct intel_panel *panel = &connector->panel;
1550
1551         panel->backlight.pwm_funcs->enable(crtc_state, conn_state,
1552                                            intel_backlight_invert_pwm_level(connector, level));
1553 }
1554
1555 static void intel_pwm_disable_backlight(const struct drm_connector_state *conn_state, u32 level)
1556 {
1557         struct intel_connector *connector = to_intel_connector(conn_state->connector);
1558         struct intel_panel *panel = &connector->panel;
1559
1560         panel->backlight.pwm_funcs->disable(conn_state,
1561                                             intel_backlight_invert_pwm_level(connector, level));
1562 }
1563
1564 static int intel_pwm_setup_backlight(struct intel_connector *connector, enum pipe pipe)
1565 {
1566         struct intel_panel *panel = &connector->panel;
1567         int ret = panel->backlight.pwm_funcs->setup(connector, pipe);
1568
1569         if (ret < 0)
1570                 return ret;
1571
1572         panel->backlight.min = panel->backlight.pwm_level_min;
1573         panel->backlight.max = panel->backlight.pwm_level_max;
1574         panel->backlight.level = intel_pwm_get_backlight(connector, pipe);
1575         panel->backlight.enabled = panel->backlight.pwm_enabled;
1576
1577         return 0;
1578 }
1579
1580 void intel_backlight_update(struct intel_atomic_state *state,
1581                             struct intel_encoder *encoder,
1582                             const struct intel_crtc_state *crtc_state,
1583                             const struct drm_connector_state *conn_state)
1584 {
1585         struct intel_connector *connector = to_intel_connector(conn_state->connector);
1586         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1587         struct intel_panel *panel = &connector->panel;
1588
1589         if (!panel->backlight.present)
1590                 return;
1591
1592         mutex_lock(&dev_priv->backlight_lock);
1593         if (!panel->backlight.enabled)
1594                 __intel_backlight_enable(crtc_state, conn_state);
1595
1596         mutex_unlock(&dev_priv->backlight_lock);
1597 }
1598
1599 int intel_backlight_setup(struct intel_connector *connector, enum pipe pipe)
1600 {
1601         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1602         struct intel_panel *panel = &connector->panel;
1603         int ret;
1604
1605         if (!dev_priv->vbt.backlight.present) {
1606                 if (dev_priv->quirks & QUIRK_BACKLIGHT_PRESENT) {
1607                         drm_dbg_kms(&dev_priv->drm,
1608                                     "no backlight present per VBT, but present per quirk\n");
1609                 } else {
1610                         drm_dbg_kms(&dev_priv->drm,
1611                                     "no backlight present per VBT\n");
1612                         return 0;
1613                 }
1614         }
1615
1616         /* ensure intel_panel has been initialized first */
1617         if (drm_WARN_ON(&dev_priv->drm, !panel->backlight.funcs))
1618                 return -ENODEV;
1619
1620         /* set level and max in panel struct */
1621         mutex_lock(&dev_priv->backlight_lock);
1622         ret = panel->backlight.funcs->setup(connector, pipe);
1623         mutex_unlock(&dev_priv->backlight_lock);
1624
1625         if (ret) {
1626                 drm_dbg_kms(&dev_priv->drm,
1627                             "failed to setup backlight for connector %s\n",
1628                             connector->base.name);
1629                 return ret;
1630         }
1631
1632         panel->backlight.present = true;
1633
1634         drm_dbg_kms(&dev_priv->drm,
1635                     "Connector %s backlight initialized, %s, brightness %u/%u\n",
1636                     connector->base.name,
1637                     str_enabled_disabled(panel->backlight.enabled),
1638                     panel->backlight.level, panel->backlight.max);
1639
1640         return 0;
1641 }
1642
1643 void intel_backlight_destroy(struct intel_panel *panel)
1644 {
1645         /* dispose of the pwm */
1646         if (panel->backlight.pwm)
1647                 pwm_put(panel->backlight.pwm);
1648
1649         panel->backlight.present = false;
1650 }
1651
1652 static const struct intel_panel_bl_funcs bxt_pwm_funcs = {
1653         .setup = bxt_setup_backlight,
1654         .enable = bxt_enable_backlight,
1655         .disable = bxt_disable_backlight,
1656         .set = bxt_set_backlight,
1657         .get = bxt_get_backlight,
1658         .hz_to_pwm = bxt_hz_to_pwm,
1659 };
1660
1661 static const struct intel_panel_bl_funcs cnp_pwm_funcs = {
1662         .setup = cnp_setup_backlight,
1663         .enable = cnp_enable_backlight,
1664         .disable = cnp_disable_backlight,
1665         .set = bxt_set_backlight,
1666         .get = bxt_get_backlight,
1667         .hz_to_pwm = cnp_hz_to_pwm,
1668 };
1669
1670 static const struct intel_panel_bl_funcs lpt_pwm_funcs = {
1671         .setup = lpt_setup_backlight,
1672         .enable = lpt_enable_backlight,
1673         .disable = lpt_disable_backlight,
1674         .set = lpt_set_backlight,
1675         .get = lpt_get_backlight,
1676         .hz_to_pwm = lpt_hz_to_pwm,
1677 };
1678
1679 static const struct intel_panel_bl_funcs spt_pwm_funcs = {
1680         .setup = lpt_setup_backlight,
1681         .enable = lpt_enable_backlight,
1682         .disable = lpt_disable_backlight,
1683         .set = lpt_set_backlight,
1684         .get = lpt_get_backlight,
1685         .hz_to_pwm = spt_hz_to_pwm,
1686 };
1687
1688 static const struct intel_panel_bl_funcs pch_pwm_funcs = {
1689         .setup = pch_setup_backlight,
1690         .enable = pch_enable_backlight,
1691         .disable = pch_disable_backlight,
1692         .set = pch_set_backlight,
1693         .get = pch_get_backlight,
1694         .hz_to_pwm = pch_hz_to_pwm,
1695 };
1696
1697 static const struct intel_panel_bl_funcs ext_pwm_funcs = {
1698         .setup = ext_pwm_setup_backlight,
1699         .enable = ext_pwm_enable_backlight,
1700         .disable = ext_pwm_disable_backlight,
1701         .set = ext_pwm_set_backlight,
1702         .get = ext_pwm_get_backlight,
1703 };
1704
1705 static const struct intel_panel_bl_funcs vlv_pwm_funcs = {
1706         .setup = vlv_setup_backlight,
1707         .enable = vlv_enable_backlight,
1708         .disable = vlv_disable_backlight,
1709         .set = vlv_set_backlight,
1710         .get = vlv_get_backlight,
1711         .hz_to_pwm = vlv_hz_to_pwm,
1712 };
1713
1714 static const struct intel_panel_bl_funcs i965_pwm_funcs = {
1715         .setup = i965_setup_backlight,
1716         .enable = i965_enable_backlight,
1717         .disable = i965_disable_backlight,
1718         .set = i9xx_set_backlight,
1719         .get = i9xx_get_backlight,
1720         .hz_to_pwm = i965_hz_to_pwm,
1721 };
1722
1723 static const struct intel_panel_bl_funcs i9xx_pwm_funcs = {
1724         .setup = i9xx_setup_backlight,
1725         .enable = i9xx_enable_backlight,
1726         .disable = i9xx_disable_backlight,
1727         .set = i9xx_set_backlight,
1728         .get = i9xx_get_backlight,
1729         .hz_to_pwm = i9xx_hz_to_pwm,
1730 };
1731
1732 static const struct intel_panel_bl_funcs pwm_bl_funcs = {
1733         .setup = intel_pwm_setup_backlight,
1734         .enable = intel_pwm_enable_backlight,
1735         .disable = intel_pwm_disable_backlight,
1736         .set = intel_pwm_set_backlight,
1737         .get = intel_pwm_get_backlight,
1738 };
1739
1740 /* Set up chip specific backlight functions */
1741 void intel_backlight_init_funcs(struct intel_panel *panel)
1742 {
1743         struct intel_connector *connector =
1744                 container_of(panel, struct intel_connector, panel);
1745         struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
1746
1747         if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI &&
1748             intel_dsi_dcs_init_backlight_funcs(connector) == 0)
1749                 return;
1750
1751         if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv)) {
1752                 panel->backlight.pwm_funcs = &bxt_pwm_funcs;
1753         } else if (INTEL_PCH_TYPE(dev_priv) >= PCH_CNP) {
1754                 panel->backlight.pwm_funcs = &cnp_pwm_funcs;
1755         } else if (INTEL_PCH_TYPE(dev_priv) >= PCH_LPT) {
1756                 if (HAS_PCH_LPT(dev_priv))
1757                         panel->backlight.pwm_funcs = &lpt_pwm_funcs;
1758                 else
1759                         panel->backlight.pwm_funcs = &spt_pwm_funcs;
1760         } else if (HAS_PCH_SPLIT(dev_priv)) {
1761                 panel->backlight.pwm_funcs = &pch_pwm_funcs;
1762         } else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
1763                 if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI) {
1764                         panel->backlight.pwm_funcs = &ext_pwm_funcs;
1765                 } else {
1766                         panel->backlight.pwm_funcs = &vlv_pwm_funcs;
1767                 }
1768         } else if (DISPLAY_VER(dev_priv) == 4) {
1769                 panel->backlight.pwm_funcs = &i965_pwm_funcs;
1770         } else {
1771                 panel->backlight.pwm_funcs = &i9xx_pwm_funcs;
1772         }
1773
1774         if (connector->base.connector_type == DRM_MODE_CONNECTOR_eDP &&
1775             intel_dp_aux_init_backlight_funcs(connector) == 0)
1776                 return;
1777
1778         /* We're using a standard PWM backlight interface */
1779         panel->backlight.funcs = &pwm_bl_funcs;
1780 }