linux/drivers/gpu/drm/i915/intel_opregion.c
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   1/*
   2 * Copyright 2008 Intel Corporation <hong.liu@intel.com>
   3 * Copyright 2008 Red Hat <mjg@redhat.com>
   4 *
   5 * Permission is hereby granted, free of charge, to any person obtaining
   6 * a copy of this software and associated documentation files (the
   7 * "Software"), to deal in the Software without restriction, including
   8 * without limitation the rights to use, copy, modify, merge, publish,
   9 * distribute, sub license, and/or sell copies of the Software, and to
  10 * permit persons to whom the Software is furnished to do so, subject to
  11 * the following conditions:
  12 *
  13 * The above copyright notice and this permission notice (including the
  14 * next paragraph) shall be included in all copies or substantial
  15 * portions of the Software.
  16 *
  17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  20 * NON-INFRINGEMENT.  IN NO EVENT SHALL INTEL AND/OR ITS SUPPLIERS BE
  21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  22 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  24 * SOFTWARE.
  25 *
  26 */
  27
  28#include <linux/acpi.h>
  29#include <linux/dmi.h>
  30#include <acpi/video.h>
  31
  32#include <drm/drmP.h>
  33#include <drm/i915_drm.h>
  34#include "i915_drv.h"
  35#include "intel_drv.h"
  36
  37#define OPREGION_HEADER_OFFSET 0
  38#define OPREGION_ACPI_OFFSET   0x100
  39#define   ACPI_CLID 0x01ac /* current lid state indicator */
  40#define   ACPI_CDCK 0x01b0 /* current docking state indicator */
  41#define OPREGION_SWSCI_OFFSET  0x200
  42#define OPREGION_ASLE_OFFSET   0x300
  43#define OPREGION_VBT_OFFSET    0x400
  44#define OPREGION_ASLE_EXT_OFFSET        0x1C00
  45
  46#define OPREGION_SIGNATURE "IntelGraphicsMem"
  47#define MBOX_ACPI      (1<<0)
  48#define MBOX_SWSCI     (1<<1)
  49#define MBOX_ASLE      (1<<2)
  50#define MBOX_ASLE_EXT  (1<<4)
  51
  52struct opregion_header {
  53        u8 signature[16];
  54        u32 size;
  55        u32 opregion_ver;
  56        u8 bios_ver[32];
  57        u8 vbios_ver[16];
  58        u8 driver_ver[16];
  59        u32 mboxes;
  60        u32 driver_model;
  61        u32 pcon;
  62        u8 dver[32];
  63        u8 rsvd[124];
  64} __packed;
  65
  66/* OpRegion mailbox #1: public ACPI methods */
  67struct opregion_acpi {
  68        u32 drdy;       /* driver readiness */
  69        u32 csts;       /* notification status */
  70        u32 cevt;       /* current event */
  71        u8 rsvd1[20];
  72        u32 didl[8];    /* supported display devices ID list */
  73        u32 cpdl[8];    /* currently presented display list */
  74        u32 cadl[8];    /* currently active display list */
  75        u32 nadl[8];    /* next active devices list */
  76        u32 aslp;       /* ASL sleep time-out */
  77        u32 tidx;       /* toggle table index */
  78        u32 chpd;       /* current hotplug enable indicator */
  79        u32 clid;       /* current lid state*/
  80        u32 cdck;       /* current docking state */
  81        u32 sxsw;       /* Sx state resume */
  82        u32 evts;       /* ASL supported events */
  83        u32 cnot;       /* current OS notification */
  84        u32 nrdy;       /* driver status */
  85        u32 did2[7];    /* extended supported display devices ID list */
  86        u32 cpd2[7];    /* extended attached display devices list */
  87        u8 rsvd2[4];
  88} __packed;
  89
  90/* OpRegion mailbox #2: SWSCI */
  91struct opregion_swsci {
  92        u32 scic;       /* SWSCI command|status|data */
  93        u32 parm;       /* command parameters */
  94        u32 dslp;       /* driver sleep time-out */
  95        u8 rsvd[244];
  96} __packed;
  97
  98/* OpRegion mailbox #3: ASLE */
  99struct opregion_asle {
 100        u32 ardy;       /* driver readiness */
 101        u32 aslc;       /* ASLE interrupt command */
 102        u32 tche;       /* technology enabled indicator */
 103        u32 alsi;       /* current ALS illuminance reading */
 104        u32 bclp;       /* backlight brightness to set */
 105        u32 pfit;       /* panel fitting state */
 106        u32 cblv;       /* current brightness level */
 107        u16 bclm[20];   /* backlight level duty cycle mapping table */
 108        u32 cpfm;       /* current panel fitting mode */
 109        u32 epfm;       /* enabled panel fitting modes */
 110        u8 plut[74];    /* panel LUT and identifier */
 111        u32 pfmb;       /* PWM freq and min brightness */
 112        u32 cddv;       /* color correction default values */
 113        u32 pcft;       /* power conservation features */
 114        u32 srot;       /* supported rotation angles */
 115        u32 iuer;       /* IUER events */
 116        u64 fdss;
 117        u32 fdsp;
 118        u32 stat;
 119        u64 rvda;       /* Physical address of raw vbt data */
 120        u32 rvds;       /* Size of raw vbt data */
 121        u8 rsvd[58];
 122} __packed;
 123
 124/* OpRegion mailbox #5: ASLE ext */
 125struct opregion_asle_ext {
 126        u32 phed;       /* Panel Header */
 127        u8 bddc[256];   /* Panel EDID */
 128        u8 rsvd[764];
 129} __packed;
 130
 131/* Driver readiness indicator */
 132#define ASLE_ARDY_READY         (1 << 0)
 133#define ASLE_ARDY_NOT_READY     (0 << 0)
 134
 135/* ASLE Interrupt Command (ASLC) bits */
 136#define ASLC_SET_ALS_ILLUM              (1 << 0)
 137#define ASLC_SET_BACKLIGHT              (1 << 1)
 138#define ASLC_SET_PFIT                   (1 << 2)
 139#define ASLC_SET_PWM_FREQ               (1 << 3)
 140#define ASLC_SUPPORTED_ROTATION_ANGLES  (1 << 4)
 141#define ASLC_BUTTON_ARRAY               (1 << 5)
 142#define ASLC_CONVERTIBLE_INDICATOR      (1 << 6)
 143#define ASLC_DOCKING_INDICATOR          (1 << 7)
 144#define ASLC_ISCT_STATE_CHANGE          (1 << 8)
 145#define ASLC_REQ_MSK                    0x1ff
 146/* response bits */
 147#define ASLC_ALS_ILLUM_FAILED           (1 << 10)
 148#define ASLC_BACKLIGHT_FAILED           (1 << 12)
 149#define ASLC_PFIT_FAILED                (1 << 14)
 150#define ASLC_PWM_FREQ_FAILED            (1 << 16)
 151#define ASLC_ROTATION_ANGLES_FAILED     (1 << 18)
 152#define ASLC_BUTTON_ARRAY_FAILED        (1 << 20)
 153#define ASLC_CONVERTIBLE_FAILED         (1 << 22)
 154#define ASLC_DOCKING_FAILED             (1 << 24)
 155#define ASLC_ISCT_STATE_FAILED          (1 << 26)
 156
 157/* Technology enabled indicator */
 158#define ASLE_TCHE_ALS_EN        (1 << 0)
 159#define ASLE_TCHE_BLC_EN        (1 << 1)
 160#define ASLE_TCHE_PFIT_EN       (1 << 2)
 161#define ASLE_TCHE_PFMB_EN       (1 << 3)
 162
 163/* ASLE backlight brightness to set */
 164#define ASLE_BCLP_VALID                (1<<31)
 165#define ASLE_BCLP_MSK          (~(1<<31))
 166
 167/* ASLE panel fitting request */
 168#define ASLE_PFIT_VALID         (1<<31)
 169#define ASLE_PFIT_CENTER (1<<0)
 170#define ASLE_PFIT_STRETCH_TEXT (1<<1)
 171#define ASLE_PFIT_STRETCH_GFX (1<<2)
 172
 173/* PWM frequency and minimum brightness */
 174#define ASLE_PFMB_BRIGHTNESS_MASK (0xff)
 175#define ASLE_PFMB_BRIGHTNESS_VALID (1<<8)
 176#define ASLE_PFMB_PWM_MASK (0x7ffffe00)
 177#define ASLE_PFMB_PWM_VALID (1<<31)
 178
 179#define ASLE_CBLV_VALID         (1<<31)
 180
 181/* IUER */
 182#define ASLE_IUER_DOCKING               (1 << 7)
 183#define ASLE_IUER_CONVERTIBLE           (1 << 6)
 184#define ASLE_IUER_ROTATION_LOCK_BTN     (1 << 4)
 185#define ASLE_IUER_VOLUME_DOWN_BTN       (1 << 3)
 186#define ASLE_IUER_VOLUME_UP_BTN         (1 << 2)
 187#define ASLE_IUER_WINDOWS_BTN           (1 << 1)
 188#define ASLE_IUER_POWER_BTN             (1 << 0)
 189
 190/* Software System Control Interrupt (SWSCI) */
 191#define SWSCI_SCIC_INDICATOR            (1 << 0)
 192#define SWSCI_SCIC_MAIN_FUNCTION_SHIFT  1
 193#define SWSCI_SCIC_MAIN_FUNCTION_MASK   (0xf << 1)
 194#define SWSCI_SCIC_SUB_FUNCTION_SHIFT   8
 195#define SWSCI_SCIC_SUB_FUNCTION_MASK    (0xff << 8)
 196#define SWSCI_SCIC_EXIT_PARAMETER_SHIFT 8
 197#define SWSCI_SCIC_EXIT_PARAMETER_MASK  (0xff << 8)
 198#define SWSCI_SCIC_EXIT_STATUS_SHIFT    5
 199#define SWSCI_SCIC_EXIT_STATUS_MASK     (7 << 5)
 200#define SWSCI_SCIC_EXIT_STATUS_SUCCESS  1
 201
 202#define SWSCI_FUNCTION_CODE(main, sub) \
 203        ((main) << SWSCI_SCIC_MAIN_FUNCTION_SHIFT | \
 204         (sub) << SWSCI_SCIC_SUB_FUNCTION_SHIFT)
 205
 206/* SWSCI: Get BIOS Data (GBDA) */
 207#define SWSCI_GBDA                      4
 208#define SWSCI_GBDA_SUPPORTED_CALLS      SWSCI_FUNCTION_CODE(SWSCI_GBDA, 0)
 209#define SWSCI_GBDA_REQUESTED_CALLBACKS  SWSCI_FUNCTION_CODE(SWSCI_GBDA, 1)
 210#define SWSCI_GBDA_BOOT_DISPLAY_PREF    SWSCI_FUNCTION_CODE(SWSCI_GBDA, 4)
 211#define SWSCI_GBDA_PANEL_DETAILS        SWSCI_FUNCTION_CODE(SWSCI_GBDA, 5)
 212#define SWSCI_GBDA_TV_STANDARD          SWSCI_FUNCTION_CODE(SWSCI_GBDA, 6)
 213#define SWSCI_GBDA_INTERNAL_GRAPHICS    SWSCI_FUNCTION_CODE(SWSCI_GBDA, 7)
 214#define SWSCI_GBDA_SPREAD_SPECTRUM      SWSCI_FUNCTION_CODE(SWSCI_GBDA, 10)
 215
 216/* SWSCI: System BIOS Callbacks (SBCB) */
 217#define SWSCI_SBCB                      6
 218#define SWSCI_SBCB_SUPPORTED_CALLBACKS  SWSCI_FUNCTION_CODE(SWSCI_SBCB, 0)
 219#define SWSCI_SBCB_INIT_COMPLETION      SWSCI_FUNCTION_CODE(SWSCI_SBCB, 1)
 220#define SWSCI_SBCB_PRE_HIRES_SET_MODE   SWSCI_FUNCTION_CODE(SWSCI_SBCB, 3)
 221#define SWSCI_SBCB_POST_HIRES_SET_MODE  SWSCI_FUNCTION_CODE(SWSCI_SBCB, 4)
 222#define SWSCI_SBCB_DISPLAY_SWITCH       SWSCI_FUNCTION_CODE(SWSCI_SBCB, 5)
 223#define SWSCI_SBCB_SET_TV_FORMAT        SWSCI_FUNCTION_CODE(SWSCI_SBCB, 6)
 224#define SWSCI_SBCB_ADAPTER_POWER_STATE  SWSCI_FUNCTION_CODE(SWSCI_SBCB, 7)
 225#define SWSCI_SBCB_DISPLAY_POWER_STATE  SWSCI_FUNCTION_CODE(SWSCI_SBCB, 8)
 226#define SWSCI_SBCB_SET_BOOT_DISPLAY     SWSCI_FUNCTION_CODE(SWSCI_SBCB, 9)
 227#define SWSCI_SBCB_SET_PANEL_DETAILS    SWSCI_FUNCTION_CODE(SWSCI_SBCB, 10)
 228#define SWSCI_SBCB_SET_INTERNAL_GFX     SWSCI_FUNCTION_CODE(SWSCI_SBCB, 11)
 229#define SWSCI_SBCB_POST_HIRES_TO_DOS_FS SWSCI_FUNCTION_CODE(SWSCI_SBCB, 16)
 230#define SWSCI_SBCB_SUSPEND_RESUME       SWSCI_FUNCTION_CODE(SWSCI_SBCB, 17)
 231#define SWSCI_SBCB_SET_SPREAD_SPECTRUM  SWSCI_FUNCTION_CODE(SWSCI_SBCB, 18)
 232#define SWSCI_SBCB_POST_VBE_PM          SWSCI_FUNCTION_CODE(SWSCI_SBCB, 19)
 233#define SWSCI_SBCB_ENABLE_DISABLE_AUDIO SWSCI_FUNCTION_CODE(SWSCI_SBCB, 21)
 234
 235/*
 236 * ACPI Specification, Revision 5.0, Appendix B.3.2 _DOD (Enumerate All Devices
 237 * Attached to the Display Adapter).
 238 */
 239#define ACPI_DISPLAY_INDEX_SHIFT                0
 240#define ACPI_DISPLAY_INDEX_MASK                 (0xf << 0)
 241#define ACPI_DISPLAY_PORT_ATTACHMENT_SHIFT      4
 242#define ACPI_DISPLAY_PORT_ATTACHMENT_MASK       (0xf << 4)
 243#define ACPI_DISPLAY_TYPE_SHIFT                 8
 244#define ACPI_DISPLAY_TYPE_MASK                  (0xf << 8)
 245#define ACPI_DISPLAY_TYPE_OTHER                 (0 << 8)
 246#define ACPI_DISPLAY_TYPE_VGA                   (1 << 8)
 247#define ACPI_DISPLAY_TYPE_TV                    (2 << 8)
 248#define ACPI_DISPLAY_TYPE_EXTERNAL_DIGITAL      (3 << 8)
 249#define ACPI_DISPLAY_TYPE_INTERNAL_DIGITAL      (4 << 8)
 250#define ACPI_VENDOR_SPECIFIC_SHIFT              12
 251#define ACPI_VENDOR_SPECIFIC_MASK               (0xf << 12)
 252#define ACPI_BIOS_CAN_DETECT                    (1 << 16)
 253#define ACPI_DEPENDS_ON_VGA                     (1 << 17)
 254#define ACPI_PIPE_ID_SHIFT                      18
 255#define ACPI_PIPE_ID_MASK                       (7 << 18)
 256#define ACPI_DEVICE_ID_SCHEME                   (1 << 31)
 257
 258#define MAX_DSLP        1500
 259
 260static int swsci(struct drm_i915_private *dev_priv,
 261                 u32 function, u32 parm, u32 *parm_out)
 262{
 263        struct opregion_swsci *swsci = dev_priv->opregion.swsci;
 264        struct pci_dev *pdev = dev_priv->drm.pdev;
 265        u32 main_function, sub_function, scic;
 266        u16 swsci_val;
 267        u32 dslp;
 268
 269        if (!swsci)
 270                return -ENODEV;
 271
 272        main_function = (function & SWSCI_SCIC_MAIN_FUNCTION_MASK) >>
 273                SWSCI_SCIC_MAIN_FUNCTION_SHIFT;
 274        sub_function = (function & SWSCI_SCIC_SUB_FUNCTION_MASK) >>
 275                SWSCI_SCIC_SUB_FUNCTION_SHIFT;
 276
 277        /* Check if we can call the function. See swsci_setup for details. */
 278        if (main_function == SWSCI_SBCB) {
 279                if ((dev_priv->opregion.swsci_sbcb_sub_functions &
 280                     (1 << sub_function)) == 0)
 281                        return -EINVAL;
 282        } else if (main_function == SWSCI_GBDA) {
 283                if ((dev_priv->opregion.swsci_gbda_sub_functions &
 284                     (1 << sub_function)) == 0)
 285                        return -EINVAL;
 286        }
 287
 288        /* Driver sleep timeout in ms. */
 289        dslp = swsci->dslp;
 290        if (!dslp) {
 291                /* The spec says 2ms should be the default, but it's too small
 292                 * for some machines. */
 293                dslp = 50;
 294        } else if (dslp > MAX_DSLP) {
 295                /* Hey bios, trust must be earned. */
 296                DRM_INFO_ONCE("ACPI BIOS requests an excessive sleep of %u ms, "
 297                              "using %u ms instead\n", dslp, MAX_DSLP);
 298                dslp = MAX_DSLP;
 299        }
 300
 301        /* The spec tells us to do this, but we are the only user... */
 302        scic = swsci->scic;
 303        if (scic & SWSCI_SCIC_INDICATOR) {
 304                DRM_DEBUG_DRIVER("SWSCI request already in progress\n");
 305                return -EBUSY;
 306        }
 307
 308        scic = function | SWSCI_SCIC_INDICATOR;
 309
 310        swsci->parm = parm;
 311        swsci->scic = scic;
 312
 313        /* Ensure SCI event is selected and event trigger is cleared. */
 314        pci_read_config_word(pdev, SWSCI, &swsci_val);
 315        if (!(swsci_val & SWSCI_SCISEL) || (swsci_val & SWSCI_GSSCIE)) {
 316                swsci_val |= SWSCI_SCISEL;
 317                swsci_val &= ~SWSCI_GSSCIE;
 318                pci_write_config_word(pdev, SWSCI, swsci_val);
 319        }
 320
 321        /* Use event trigger to tell bios to check the mail. */
 322        swsci_val |= SWSCI_GSSCIE;
 323        pci_write_config_word(pdev, SWSCI, swsci_val);
 324
 325        /* Poll for the result. */
 326#define C (((scic = swsci->scic) & SWSCI_SCIC_INDICATOR) == 0)
 327        if (wait_for(C, dslp)) {
 328                DRM_DEBUG_DRIVER("SWSCI request timed out\n");
 329                return -ETIMEDOUT;
 330        }
 331
 332        scic = (scic & SWSCI_SCIC_EXIT_STATUS_MASK) >>
 333                SWSCI_SCIC_EXIT_STATUS_SHIFT;
 334
 335        /* Note: scic == 0 is an error! */
 336        if (scic != SWSCI_SCIC_EXIT_STATUS_SUCCESS) {
 337                DRM_DEBUG_DRIVER("SWSCI request error %u\n", scic);
 338                return -EIO;
 339        }
 340
 341        if (parm_out)
 342                *parm_out = swsci->parm;
 343
 344        return 0;
 345
 346#undef C
 347}
 348
 349#define DISPLAY_TYPE_CRT                        0
 350#define DISPLAY_TYPE_TV                         1
 351#define DISPLAY_TYPE_EXTERNAL_FLAT_PANEL        2
 352#define DISPLAY_TYPE_INTERNAL_FLAT_PANEL        3
 353
 354int intel_opregion_notify_encoder(struct intel_encoder *intel_encoder,
 355                                  bool enable)
 356{
 357        struct drm_i915_private *dev_priv = to_i915(intel_encoder->base.dev);
 358        u32 parm = 0;
 359        u32 type = 0;
 360        u32 port;
 361
 362        /* don't care about old stuff for now */
 363        if (!HAS_DDI(dev_priv))
 364                return 0;
 365
 366        if (intel_encoder->type == INTEL_OUTPUT_DSI)
 367                port = 0;
 368        else
 369                port = intel_ddi_get_encoder_port(intel_encoder);
 370
 371        if (port == PORT_E)  {
 372                port = 0;
 373        } else {
 374                parm |= 1 << port;
 375                port++;
 376        }
 377
 378        if (!enable)
 379                parm |= 4 << 8;
 380
 381        switch (intel_encoder->type) {
 382        case INTEL_OUTPUT_ANALOG:
 383                type = DISPLAY_TYPE_CRT;
 384                break;
 385        case INTEL_OUTPUT_UNKNOWN:
 386        case INTEL_OUTPUT_DP:
 387        case INTEL_OUTPUT_HDMI:
 388        case INTEL_OUTPUT_DP_MST:
 389                type = DISPLAY_TYPE_EXTERNAL_FLAT_PANEL;
 390                break;
 391        case INTEL_OUTPUT_EDP:
 392        case INTEL_OUTPUT_DSI:
 393                type = DISPLAY_TYPE_INTERNAL_FLAT_PANEL;
 394                break;
 395        default:
 396                WARN_ONCE(1, "unsupported intel_encoder type %d\n",
 397                          intel_encoder->type);
 398                return -EINVAL;
 399        }
 400
 401        parm |= type << (16 + port * 3);
 402
 403        return swsci(dev_priv, SWSCI_SBCB_DISPLAY_POWER_STATE, parm, NULL);
 404}
 405
 406static const struct {
 407        pci_power_t pci_power_state;
 408        u32 parm;
 409} power_state_map[] = {
 410        { PCI_D0,       0x00 },
 411        { PCI_D1,       0x01 },
 412        { PCI_D2,       0x02 },
 413        { PCI_D3hot,    0x04 },
 414        { PCI_D3cold,   0x04 },
 415};
 416
 417int intel_opregion_notify_adapter(struct drm_i915_private *dev_priv,
 418                                  pci_power_t state)
 419{
 420        int i;
 421
 422        if (!HAS_DDI(dev_priv))
 423                return 0;
 424
 425        for (i = 0; i < ARRAY_SIZE(power_state_map); i++) {
 426                if (state == power_state_map[i].pci_power_state)
 427                        return swsci(dev_priv, SWSCI_SBCB_ADAPTER_POWER_STATE,
 428                                     power_state_map[i].parm, NULL);
 429        }
 430
 431        return -EINVAL;
 432}
 433
 434static u32 asle_set_backlight(struct drm_i915_private *dev_priv, u32 bclp)
 435{
 436        struct intel_connector *connector;
 437        struct drm_connector_list_iter conn_iter;
 438        struct opregion_asle *asle = dev_priv->opregion.asle;
 439        struct drm_device *dev = &dev_priv->drm;
 440
 441        DRM_DEBUG_DRIVER("bclp = 0x%08x\n", bclp);
 442
 443        if (acpi_video_get_backlight_type() == acpi_backlight_native) {
 444                DRM_DEBUG_KMS("opregion backlight request ignored\n");
 445                return 0;
 446        }
 447
 448        if (!(bclp & ASLE_BCLP_VALID))
 449                return ASLC_BACKLIGHT_FAILED;
 450
 451        bclp &= ASLE_BCLP_MSK;
 452        if (bclp > 255)
 453                return ASLC_BACKLIGHT_FAILED;
 454
 455        drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 456
 457        /*
 458         * Update backlight on all connectors that support backlight (usually
 459         * only one).
 460         */
 461        DRM_DEBUG_KMS("updating opregion backlight %d/255\n", bclp);
 462        drm_connector_list_iter_begin(dev, &conn_iter);
 463        for_each_intel_connector_iter(connector, &conn_iter)
 464                intel_panel_set_backlight_acpi(connector, bclp, 255);
 465        drm_connector_list_iter_end(&conn_iter);
 466        asle->cblv = DIV_ROUND_UP(bclp * 100, 255) | ASLE_CBLV_VALID;
 467
 468        drm_modeset_unlock(&dev->mode_config.connection_mutex);
 469
 470
 471        return 0;
 472}
 473
 474static u32 asle_set_als_illum(struct drm_i915_private *dev_priv, u32 alsi)
 475{
 476        /* alsi is the current ALS reading in lux. 0 indicates below sensor
 477           range, 0xffff indicates above sensor range. 1-0xfffe are valid */
 478        DRM_DEBUG_DRIVER("Illum is not supported\n");
 479        return ASLC_ALS_ILLUM_FAILED;
 480}
 481
 482static u32 asle_set_pwm_freq(struct drm_i915_private *dev_priv, u32 pfmb)
 483{
 484        DRM_DEBUG_DRIVER("PWM freq is not supported\n");
 485        return ASLC_PWM_FREQ_FAILED;
 486}
 487
 488static u32 asle_set_pfit(struct drm_i915_private *dev_priv, u32 pfit)
 489{
 490        /* Panel fitting is currently controlled by the X code, so this is a
 491           noop until modesetting support works fully */
 492        DRM_DEBUG_DRIVER("Pfit is not supported\n");
 493        return ASLC_PFIT_FAILED;
 494}
 495
 496static u32 asle_set_supported_rotation_angles(struct drm_i915_private *dev_priv, u32 srot)
 497{
 498        DRM_DEBUG_DRIVER("SROT is not supported\n");
 499        return ASLC_ROTATION_ANGLES_FAILED;
 500}
 501
 502static u32 asle_set_button_array(struct drm_i915_private *dev_priv, u32 iuer)
 503{
 504        if (!iuer)
 505                DRM_DEBUG_DRIVER("Button array event is not supported (nothing)\n");
 506        if (iuer & ASLE_IUER_ROTATION_LOCK_BTN)
 507                DRM_DEBUG_DRIVER("Button array event is not supported (rotation lock)\n");
 508        if (iuer & ASLE_IUER_VOLUME_DOWN_BTN)
 509                DRM_DEBUG_DRIVER("Button array event is not supported (volume down)\n");
 510        if (iuer & ASLE_IUER_VOLUME_UP_BTN)
 511                DRM_DEBUG_DRIVER("Button array event is not supported (volume up)\n");
 512        if (iuer & ASLE_IUER_WINDOWS_BTN)
 513                DRM_DEBUG_DRIVER("Button array event is not supported (windows)\n");
 514        if (iuer & ASLE_IUER_POWER_BTN)
 515                DRM_DEBUG_DRIVER("Button array event is not supported (power)\n");
 516
 517        return ASLC_BUTTON_ARRAY_FAILED;
 518}
 519
 520static u32 asle_set_convertible(struct drm_i915_private *dev_priv, u32 iuer)
 521{
 522        if (iuer & ASLE_IUER_CONVERTIBLE)
 523                DRM_DEBUG_DRIVER("Convertible is not supported (clamshell)\n");
 524        else
 525                DRM_DEBUG_DRIVER("Convertible is not supported (slate)\n");
 526
 527        return ASLC_CONVERTIBLE_FAILED;
 528}
 529
 530static u32 asle_set_docking(struct drm_i915_private *dev_priv, u32 iuer)
 531{
 532        if (iuer & ASLE_IUER_DOCKING)
 533                DRM_DEBUG_DRIVER("Docking is not supported (docked)\n");
 534        else
 535                DRM_DEBUG_DRIVER("Docking is not supported (undocked)\n");
 536
 537        return ASLC_DOCKING_FAILED;
 538}
 539
 540static u32 asle_isct_state(struct drm_i915_private *dev_priv)
 541{
 542        DRM_DEBUG_DRIVER("ISCT is not supported\n");
 543        return ASLC_ISCT_STATE_FAILED;
 544}
 545
 546static void asle_work(struct work_struct *work)
 547{
 548        struct intel_opregion *opregion =
 549                container_of(work, struct intel_opregion, asle_work);
 550        struct drm_i915_private *dev_priv =
 551                container_of(opregion, struct drm_i915_private, opregion);
 552        struct opregion_asle *asle = dev_priv->opregion.asle;
 553        u32 aslc_stat = 0;
 554        u32 aslc_req;
 555
 556        if (!asle)
 557                return;
 558
 559        aslc_req = asle->aslc;
 560
 561        if (!(aslc_req & ASLC_REQ_MSK)) {
 562                DRM_DEBUG_DRIVER("No request on ASLC interrupt 0x%08x\n",
 563                                 aslc_req);
 564                return;
 565        }
 566
 567        if (aslc_req & ASLC_SET_ALS_ILLUM)
 568                aslc_stat |= asle_set_als_illum(dev_priv, asle->alsi);
 569
 570        if (aslc_req & ASLC_SET_BACKLIGHT)
 571                aslc_stat |= asle_set_backlight(dev_priv, asle->bclp);
 572
 573        if (aslc_req & ASLC_SET_PFIT)
 574                aslc_stat |= asle_set_pfit(dev_priv, asle->pfit);
 575
 576        if (aslc_req & ASLC_SET_PWM_FREQ)
 577                aslc_stat |= asle_set_pwm_freq(dev_priv, asle->pfmb);
 578
 579        if (aslc_req & ASLC_SUPPORTED_ROTATION_ANGLES)
 580                aslc_stat |= asle_set_supported_rotation_angles(dev_priv,
 581                                                        asle->srot);
 582
 583        if (aslc_req & ASLC_BUTTON_ARRAY)
 584                aslc_stat |= asle_set_button_array(dev_priv, asle->iuer);
 585
 586        if (aslc_req & ASLC_CONVERTIBLE_INDICATOR)
 587                aslc_stat |= asle_set_convertible(dev_priv, asle->iuer);
 588
 589        if (aslc_req & ASLC_DOCKING_INDICATOR)
 590                aslc_stat |= asle_set_docking(dev_priv, asle->iuer);
 591
 592        if (aslc_req & ASLC_ISCT_STATE_CHANGE)
 593                aslc_stat |= asle_isct_state(dev_priv);
 594
 595        asle->aslc = aslc_stat;
 596}
 597
 598void intel_opregion_asle_intr(struct drm_i915_private *dev_priv)
 599{
 600        if (dev_priv->opregion.asle)
 601                schedule_work(&dev_priv->opregion.asle_work);
 602}
 603
 604#define ACPI_EV_DISPLAY_SWITCH (1<<0)
 605#define ACPI_EV_LID            (1<<1)
 606#define ACPI_EV_DOCK           (1<<2)
 607
 608static struct intel_opregion *system_opregion;
 609
 610static int intel_opregion_video_event(struct notifier_block *nb,
 611                                      unsigned long val, void *data)
 612{
 613        /* The only video events relevant to opregion are 0x80. These indicate
 614           either a docking event, lid switch or display switch request. In
 615           Linux, these are handled by the dock, button and video drivers.
 616        */
 617
 618        struct acpi_bus_event *event = data;
 619        struct opregion_acpi *acpi;
 620        int ret = NOTIFY_OK;
 621
 622        if (strcmp(event->device_class, ACPI_VIDEO_CLASS) != 0)
 623                return NOTIFY_DONE;
 624
 625        if (!system_opregion)
 626                return NOTIFY_DONE;
 627
 628        acpi = system_opregion->acpi;
 629
 630        if (event->type == 0x80 && ((acpi->cevt & 1) == 0))
 631                ret = NOTIFY_BAD;
 632
 633        acpi->csts = 0;
 634
 635        return ret;
 636}
 637
 638static struct notifier_block intel_opregion_notifier = {
 639        .notifier_call = intel_opregion_video_event,
 640};
 641
 642/*
 643 * Initialise the DIDL field in opregion. This passes a list of devices to
 644 * the firmware. Values are defined by section B.4.2 of the ACPI specification
 645 * (version 3)
 646 */
 647
 648static void set_did(struct intel_opregion *opregion, int i, u32 val)
 649{
 650        if (i < ARRAY_SIZE(opregion->acpi->didl)) {
 651                opregion->acpi->didl[i] = val;
 652        } else {
 653                i -= ARRAY_SIZE(opregion->acpi->didl);
 654
 655                if (WARN_ON(i >= ARRAY_SIZE(opregion->acpi->did2)))
 656                        return;
 657
 658                opregion->acpi->did2[i] = val;
 659        }
 660}
 661
 662static u32 acpi_display_type(struct intel_connector *connector)
 663{
 664        u32 display_type;
 665
 666        switch (connector->base.connector_type) {
 667        case DRM_MODE_CONNECTOR_VGA:
 668        case DRM_MODE_CONNECTOR_DVIA:
 669                display_type = ACPI_DISPLAY_TYPE_VGA;
 670                break;
 671        case DRM_MODE_CONNECTOR_Composite:
 672        case DRM_MODE_CONNECTOR_SVIDEO:
 673        case DRM_MODE_CONNECTOR_Component:
 674        case DRM_MODE_CONNECTOR_9PinDIN:
 675        case DRM_MODE_CONNECTOR_TV:
 676                display_type = ACPI_DISPLAY_TYPE_TV;
 677                break;
 678        case DRM_MODE_CONNECTOR_DVII:
 679        case DRM_MODE_CONNECTOR_DVID:
 680        case DRM_MODE_CONNECTOR_DisplayPort:
 681        case DRM_MODE_CONNECTOR_HDMIA:
 682        case DRM_MODE_CONNECTOR_HDMIB:
 683                display_type = ACPI_DISPLAY_TYPE_EXTERNAL_DIGITAL;
 684                break;
 685        case DRM_MODE_CONNECTOR_LVDS:
 686        case DRM_MODE_CONNECTOR_eDP:
 687        case DRM_MODE_CONNECTOR_DSI:
 688                display_type = ACPI_DISPLAY_TYPE_INTERNAL_DIGITAL;
 689                break;
 690        case DRM_MODE_CONNECTOR_Unknown:
 691        case DRM_MODE_CONNECTOR_VIRTUAL:
 692                display_type = ACPI_DISPLAY_TYPE_OTHER;
 693                break;
 694        default:
 695                MISSING_CASE(connector->base.connector_type);
 696                display_type = ACPI_DISPLAY_TYPE_OTHER;
 697                break;
 698        }
 699
 700        return display_type;
 701}
 702
 703static void intel_didl_outputs(struct drm_i915_private *dev_priv)
 704{
 705        struct intel_opregion *opregion = &dev_priv->opregion;
 706        struct intel_connector *connector;
 707        struct drm_connector_list_iter conn_iter;
 708        int i = 0, max_outputs;
 709        int display_index[16] = {};
 710
 711        /*
 712         * In theory, did2, the extended didl, gets added at opregion version
 713         * 3.0. In practice, however, we're supposed to set it for earlier
 714         * versions as well, since a BIOS that doesn't understand did2 should
 715         * not look at it anyway. Use a variable so we can tweak this if a need
 716         * arises later.
 717         */
 718        max_outputs = ARRAY_SIZE(opregion->acpi->didl) +
 719                ARRAY_SIZE(opregion->acpi->did2);
 720
 721        drm_connector_list_iter_begin(&dev_priv->drm, &conn_iter);
 722        for_each_intel_connector_iter(connector, &conn_iter) {
 723                u32 device_id, type;
 724
 725                device_id = acpi_display_type(connector);
 726
 727                /* Use display type specific display index. */
 728                type = (device_id & ACPI_DISPLAY_TYPE_MASK)
 729                        >> ACPI_DISPLAY_TYPE_SHIFT;
 730                device_id |= display_index[type]++ << ACPI_DISPLAY_INDEX_SHIFT;
 731
 732                connector->acpi_device_id = device_id;
 733                if (i < max_outputs)
 734                        set_did(opregion, i, device_id);
 735                i++;
 736        }
 737        drm_connector_list_iter_end(&conn_iter);
 738
 739        DRM_DEBUG_KMS("%d outputs detected\n", i);
 740
 741        if (i > max_outputs)
 742                DRM_ERROR("More than %d outputs in connector list\n",
 743                          max_outputs);
 744
 745        /* If fewer than max outputs, the list must be null terminated */
 746        if (i < max_outputs)
 747                set_did(opregion, i, 0);
 748}
 749
 750static void intel_setup_cadls(struct drm_i915_private *dev_priv)
 751{
 752        struct intel_opregion *opregion = &dev_priv->opregion;
 753        struct intel_connector *connector;
 754        struct drm_connector_list_iter conn_iter;
 755        int i = 0;
 756
 757        /*
 758         * Initialize the CADL field from the connector device ids. This is
 759         * essentially the same as copying from the DIDL. Technically, this is
 760         * not always correct as display outputs may exist, but not active. This
 761         * initialization is necessary for some Clevo laptops that check this
 762         * field before processing the brightness and display switching hotkeys.
 763         *
 764         * Note that internal panels should be at the front of the connector
 765         * list already, ensuring they're not left out.
 766         */
 767        drm_connector_list_iter_begin(&dev_priv->drm, &conn_iter);
 768        for_each_intel_connector_iter(connector, &conn_iter) {
 769                if (i >= ARRAY_SIZE(opregion->acpi->cadl))
 770                        break;
 771                opregion->acpi->cadl[i++] = connector->acpi_device_id;
 772        }
 773        drm_connector_list_iter_end(&conn_iter);
 774
 775        /* If fewer than 8 active devices, the list must be null terminated */
 776        if (i < ARRAY_SIZE(opregion->acpi->cadl))
 777                opregion->acpi->cadl[i] = 0;
 778}
 779
 780void intel_opregion_register(struct drm_i915_private *dev_priv)
 781{
 782        struct intel_opregion *opregion = &dev_priv->opregion;
 783
 784        if (!opregion->header)
 785                return;
 786
 787        if (opregion->acpi) {
 788                intel_didl_outputs(dev_priv);
 789                intel_setup_cadls(dev_priv);
 790
 791                /* Notify BIOS we are ready to handle ACPI video ext notifs.
 792                 * Right now, all the events are handled by the ACPI video module.
 793                 * We don't actually need to do anything with them. */
 794                opregion->acpi->csts = 0;
 795                opregion->acpi->drdy = 1;
 796
 797                system_opregion = opregion;
 798                register_acpi_notifier(&intel_opregion_notifier);
 799        }
 800
 801        if (opregion->asle) {
 802                opregion->asle->tche = ASLE_TCHE_BLC_EN;
 803                opregion->asle->ardy = ASLE_ARDY_READY;
 804        }
 805}
 806
 807void intel_opregion_unregister(struct drm_i915_private *dev_priv)
 808{
 809        struct intel_opregion *opregion = &dev_priv->opregion;
 810
 811        if (!opregion->header)
 812                return;
 813
 814        if (opregion->asle)
 815                opregion->asle->ardy = ASLE_ARDY_NOT_READY;
 816
 817        cancel_work_sync(&dev_priv->opregion.asle_work);
 818
 819        if (opregion->acpi) {
 820                opregion->acpi->drdy = 0;
 821
 822                system_opregion = NULL;
 823                unregister_acpi_notifier(&intel_opregion_notifier);
 824        }
 825
 826        /* just clear all opregion memory pointers now */
 827        memunmap(opregion->header);
 828        if (opregion->rvda) {
 829                memunmap(opregion->rvda);
 830                opregion->rvda = NULL;
 831        }
 832        opregion->header = NULL;
 833        opregion->acpi = NULL;
 834        opregion->swsci = NULL;
 835        opregion->asle = NULL;
 836        opregion->vbt = NULL;
 837        opregion->lid_state = NULL;
 838}
 839
 840static void swsci_setup(struct drm_i915_private *dev_priv)
 841{
 842        struct intel_opregion *opregion = &dev_priv->opregion;
 843        bool requested_callbacks = false;
 844        u32 tmp;
 845
 846        /* Sub-function code 0 is okay, let's allow them. */
 847        opregion->swsci_gbda_sub_functions = 1;
 848        opregion->swsci_sbcb_sub_functions = 1;
 849
 850        /* We use GBDA to ask for supported GBDA calls. */
 851        if (swsci(dev_priv, SWSCI_GBDA_SUPPORTED_CALLS, 0, &tmp) == 0) {
 852                /* make the bits match the sub-function codes */
 853                tmp <<= 1;
 854                opregion->swsci_gbda_sub_functions |= tmp;
 855        }
 856
 857        /*
 858         * We also use GBDA to ask for _requested_ SBCB callbacks. The driver
 859         * must not call interfaces that are not specifically requested by the
 860         * bios.
 861         */
 862        if (swsci(dev_priv, SWSCI_GBDA_REQUESTED_CALLBACKS, 0, &tmp) == 0) {
 863                /* here, the bits already match sub-function codes */
 864                opregion->swsci_sbcb_sub_functions |= tmp;
 865                requested_callbacks = true;
 866        }
 867
 868        /*
 869         * But we use SBCB to ask for _supported_ SBCB calls. This does not mean
 870         * the callback is _requested_. But we still can't call interfaces that
 871         * are not requested.
 872         */
 873        if (swsci(dev_priv, SWSCI_SBCB_SUPPORTED_CALLBACKS, 0, &tmp) == 0) {
 874                /* make the bits match the sub-function codes */
 875                u32 low = tmp & 0x7ff;
 876                u32 high = tmp & ~0xfff; /* bit 11 is reserved */
 877                tmp = (high << 4) | (low << 1) | 1;
 878
 879                /* best guess what to do with supported wrt requested */
 880                if (requested_callbacks) {
 881                        u32 req = opregion->swsci_sbcb_sub_functions;
 882                        if ((req & tmp) != req)
 883                                DRM_DEBUG_DRIVER("SWSCI BIOS requested (%08x) SBCB callbacks that are not supported (%08x)\n", req, tmp);
 884                        /* XXX: for now, trust the requested callbacks */
 885                        /* opregion->swsci_sbcb_sub_functions &= tmp; */
 886                } else {
 887                        opregion->swsci_sbcb_sub_functions |= tmp;
 888                }
 889        }
 890
 891        DRM_DEBUG_DRIVER("SWSCI GBDA callbacks %08x, SBCB callbacks %08x\n",
 892                         opregion->swsci_gbda_sub_functions,
 893                         opregion->swsci_sbcb_sub_functions);
 894}
 895
 896static int intel_no_opregion_vbt_callback(const struct dmi_system_id *id)
 897{
 898        DRM_DEBUG_KMS("Falling back to manually reading VBT from "
 899                      "VBIOS ROM for %s\n", id->ident);
 900        return 1;
 901}
 902
 903static const struct dmi_system_id intel_no_opregion_vbt[] = {
 904        {
 905                .callback = intel_no_opregion_vbt_callback,
 906                .ident = "ThinkCentre A57",
 907                .matches = {
 908                        DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 909                        DMI_MATCH(DMI_PRODUCT_NAME, "97027RG"),
 910                },
 911        },
 912        { }
 913};
 914
 915int intel_opregion_setup(struct drm_i915_private *dev_priv)
 916{
 917        struct intel_opregion *opregion = &dev_priv->opregion;
 918        struct pci_dev *pdev = dev_priv->drm.pdev;
 919        u32 asls, mboxes;
 920        char buf[sizeof(OPREGION_SIGNATURE)];
 921        int err = 0;
 922        void *base;
 923        const void *vbt;
 924        u32 vbt_size;
 925
 926        BUILD_BUG_ON(sizeof(struct opregion_header) != 0x100);
 927        BUILD_BUG_ON(sizeof(struct opregion_acpi) != 0x100);
 928        BUILD_BUG_ON(sizeof(struct opregion_swsci) != 0x100);
 929        BUILD_BUG_ON(sizeof(struct opregion_asle) != 0x100);
 930        BUILD_BUG_ON(sizeof(struct opregion_asle_ext) != 0x400);
 931
 932        pci_read_config_dword(pdev, ASLS, &asls);
 933        DRM_DEBUG_DRIVER("graphic opregion physical addr: 0x%x\n", asls);
 934        if (asls == 0) {
 935                DRM_DEBUG_DRIVER("ACPI OpRegion not supported!\n");
 936                return -ENOTSUPP;
 937        }
 938
 939        INIT_WORK(&opregion->asle_work, asle_work);
 940
 941        base = memremap(asls, OPREGION_SIZE, MEMREMAP_WB);
 942        if (!base)
 943                return -ENOMEM;
 944
 945        memcpy(buf, base, sizeof(buf));
 946
 947        if (memcmp(buf, OPREGION_SIGNATURE, 16)) {
 948                DRM_DEBUG_DRIVER("opregion signature mismatch\n");
 949                err = -EINVAL;
 950                goto err_out;
 951        }
 952        opregion->header = base;
 953        opregion->lid_state = base + ACPI_CLID;
 954
 955        mboxes = opregion->header->mboxes;
 956        if (mboxes & MBOX_ACPI) {
 957                DRM_DEBUG_DRIVER("Public ACPI methods supported\n");
 958                opregion->acpi = base + OPREGION_ACPI_OFFSET;
 959        }
 960
 961        if (mboxes & MBOX_SWSCI) {
 962                DRM_DEBUG_DRIVER("SWSCI supported\n");
 963                opregion->swsci = base + OPREGION_SWSCI_OFFSET;
 964                swsci_setup(dev_priv);
 965        }
 966
 967        if (mboxes & MBOX_ASLE) {
 968                DRM_DEBUG_DRIVER("ASLE supported\n");
 969                opregion->asle = base + OPREGION_ASLE_OFFSET;
 970
 971                opregion->asle->ardy = ASLE_ARDY_NOT_READY;
 972        }
 973
 974        if (mboxes & MBOX_ASLE_EXT)
 975                DRM_DEBUG_DRIVER("ASLE extension supported\n");
 976
 977        if (dmi_check_system(intel_no_opregion_vbt))
 978                goto out;
 979
 980        if (opregion->header->opregion_ver >= 2 && opregion->asle &&
 981            opregion->asle->rvda && opregion->asle->rvds) {
 982                opregion->rvda = memremap(opregion->asle->rvda,
 983                                          opregion->asle->rvds,
 984                                          MEMREMAP_WB);
 985                vbt = opregion->rvda;
 986                vbt_size = opregion->asle->rvds;
 987                if (intel_bios_is_valid_vbt(vbt, vbt_size)) {
 988                        DRM_DEBUG_KMS("Found valid VBT in ACPI OpRegion (RVDA)\n");
 989                        opregion->vbt = vbt;
 990                        opregion->vbt_size = vbt_size;
 991                        goto out;
 992                } else {
 993                        DRM_DEBUG_KMS("Invalid VBT in ACPI OpRegion (RVDA)\n");
 994                }
 995        }
 996
 997        vbt = base + OPREGION_VBT_OFFSET;
 998        /*
 999         * The VBT specification says that if the ASLE ext mailbox is not used
1000         * its area is reserved, but on some CHT boards the VBT extends into the
1001         * ASLE ext area. Allow this even though it is against the spec, so we
1002         * do not end up rejecting the VBT on those boards (and end up not
1003         * finding the LCD panel because of this).
1004         */
1005        vbt_size = (mboxes & MBOX_ASLE_EXT) ?
1006                OPREGION_ASLE_EXT_OFFSET : OPREGION_SIZE;
1007        vbt_size -= OPREGION_VBT_OFFSET;
1008        if (intel_bios_is_valid_vbt(vbt, vbt_size)) {
1009                DRM_DEBUG_KMS("Found valid VBT in ACPI OpRegion (Mailbox #4)\n");
1010                opregion->vbt = vbt;
1011                opregion->vbt_size = vbt_size;
1012        } else {
1013                DRM_DEBUG_KMS("Invalid VBT in ACPI OpRegion (Mailbox #4)\n");
1014        }
1015
1016out:
1017        return 0;
1018
1019err_out:
1020        memunmap(base);
1021        return err;
1022}
1023
1024static int intel_use_opregion_panel_type_callback(const struct dmi_system_id *id)
1025{
1026        DRM_INFO("Using panel type from OpRegion on %s\n", id->ident);
1027        return 1;
1028}
1029
1030static const struct dmi_system_id intel_use_opregion_panel_type[] = {
1031        {
1032                .callback = intel_use_opregion_panel_type_callback,
1033                .ident = "Conrac GmbH IX45GM2",
1034                .matches = {DMI_MATCH(DMI_SYS_VENDOR, "Conrac GmbH"),
1035                            DMI_MATCH(DMI_PRODUCT_NAME, "IX45GM2"),
1036                },
1037        },
1038        { }
1039};
1040
1041int
1042intel_opregion_get_panel_type(struct drm_i915_private *dev_priv)
1043{
1044        u32 panel_details;
1045        int ret;
1046
1047        ret = swsci(dev_priv, SWSCI_GBDA_PANEL_DETAILS, 0x0, &panel_details);
1048        if (ret) {
1049                DRM_DEBUG_KMS("Failed to get panel details from OpRegion (%d)\n",
1050                              ret);
1051                return ret;
1052        }
1053
1054        ret = (panel_details >> 8) & 0xff;
1055        if (ret > 0x10) {
1056                DRM_DEBUG_KMS("Invalid OpRegion panel type 0x%x\n", ret);
1057                return -EINVAL;
1058        }
1059
1060        /* fall back to VBT panel type? */
1061        if (ret == 0x0) {
1062                DRM_DEBUG_KMS("No panel type in OpRegion\n");
1063                return -ENODEV;
1064        }
1065
1066        /*
1067         * So far we know that some machined must use it, others must not use it.
1068         * There doesn't seem to be any way to determine which way to go, except
1069         * via a quirk list :(
1070         */
1071        if (!dmi_check_system(intel_use_opregion_panel_type)) {
1072                DRM_DEBUG_KMS("Ignoring OpRegion panel type (%d)\n", ret - 1);
1073                return -ENODEV;
1074        }
1075
1076        return ret - 1;
1077}
1078