LXR linux/drivers/gpu/drm/i915/display/intel_dp_aux

   1/*
   2 * Copyright © 2015 Intel Corporation
   3 *
   4 * Permission is hereby granted, free of charge, to any person obtaining a
   5 * copy of this software and associated documentation files (the "Software"),
   6 * to deal in the Software without restriction, including without limitation
   7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8 * and/or sell copies of the Software, and to permit persons to whom the
   9 * Software is furnished to do so, subject to the following conditions:
  10 *
  11 * The above copyright notice and this permission notice (including the next
  12 * paragraph) shall be included in all copies or substantial portions of the
  13 * Software.
  14 *
  15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21 * IN THE SOFTWARE.
  22 *
  23 */
  24
  25/*
  26 * Laptops with Intel GPUs which have panels that support controlling the
  27 * backlight through DP AUX can actually use two different interfaces: Intel's
  28 * proprietary DP AUX backlight interface, and the standard VESA backlight
  29 * interface. Unfortunately, at the time of writing this a lot of laptops will
  30 * advertise support for the standard VESA backlight interface when they
  31 * don't properly support it. However, on these systems the Intel backlight
  32 * interface generally does work properly. Additionally, these systems will
  33 * usually just indicate that they use PWM backlight controls in their VBIOS
  34 * for some reason.
  35 */
  36
  37#include "intel_display_types.h"
  38#include "intel_dp_aux_backlight.h"
  39#include "intel_panel.h"
  40
  41/* TODO:
  42 * Implement HDR, right now we just implement the bare minimum to bring us back into SDR mode so we
  43 * can make people's backlights work in the mean time
  44 */
  45
  46/*
  47 * DP AUX registers for Intel's proprietary HDR backlight interface. We define
  48 * them here since we'll likely be the only driver to ever use these.
  49 */
  50#define INTEL_EDP_HDR_TCON_CAP0                                        0x340
  51
  52#define INTEL_EDP_HDR_TCON_CAP1                                        0x341
  53# define INTEL_EDP_HDR_TCON_2084_DECODE_CAP                           BIT(0)
  54# define INTEL_EDP_HDR_TCON_2020_GAMUT_CAP                            BIT(1)
  55# define INTEL_EDP_HDR_TCON_TONE_MAPPING_CAP                          BIT(2)
  56# define INTEL_EDP_HDR_TCON_SEGMENTED_BACKLIGHT_CAP                   BIT(3)
  57# define INTEL_EDP_HDR_TCON_BRIGHTNESS_NITS_CAP                       BIT(4)
  58# define INTEL_EDP_HDR_TCON_OPTIMIZATION_CAP                          BIT(5)
  59# define INTEL_EDP_HDR_TCON_SDP_COLORIMETRY_CAP                       BIT(6)
  60# define INTEL_EDP_HDR_TCON_SRGB_TO_PANEL_GAMUT_CONVERSION_CAP        BIT(7)
  61
  62#define INTEL_EDP_HDR_TCON_CAP2                                        0x342
  63# define INTEL_EDP_SDR_TCON_BRIGHTNESS_AUX_CAP                        BIT(0)
  64
  65#define INTEL_EDP_HDR_TCON_CAP3                                        0x343
  66
  67#define INTEL_EDP_HDR_GETSET_CTRL_PARAMS                               0x344
  68# define INTEL_EDP_HDR_TCON_2084_DECODE_ENABLE                        BIT(0)
  69# define INTEL_EDP_HDR_TCON_2020_GAMUT_ENABLE                         BIT(1)
  70# define INTEL_EDP_HDR_TCON_TONE_MAPPING_ENABLE                       BIT(2) /* Pre-TGL+ */
  71# define INTEL_EDP_HDR_TCON_SEGMENTED_BACKLIGHT_ENABLE                BIT(3)
  72# define INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE                     BIT(4)
  73# define INTEL_EDP_HDR_TCON_SRGB_TO_PANEL_GAMUT_ENABLE                BIT(5)
  74/* Bit 6 is reserved */
  75# define INTEL_EDP_HDR_TCON_SDP_COLORIMETRY_ENABLE                    BIT(7)
  76
  77#define INTEL_EDP_HDR_CONTENT_LUMINANCE                                0x346 /* Pre-TGL+ */
  78#define INTEL_EDP_HDR_PANEL_LUMINANCE_OVERRIDE                         0x34A
  79#define INTEL_EDP_SDR_LUMINANCE_LEVEL                                  0x352
  80#define INTEL_EDP_BRIGHTNESS_NITS_LSB                                  0x354
  81#define INTEL_EDP_BRIGHTNESS_NITS_MSB                                  0x355
  82#define INTEL_EDP_BRIGHTNESS_DELAY_FRAMES                              0x356
  83#define INTEL_EDP_BRIGHTNESS_PER_FRAME_STEPS                           0x357
  84
  85#define INTEL_EDP_BRIGHTNESS_OPTIMIZATION_0                            0x358
  86# define INTEL_EDP_TCON_USAGE_MASK                             GENMASK(0, 3)
  87# define INTEL_EDP_TCON_USAGE_UNKNOWN                                    0x0
  88# define INTEL_EDP_TCON_USAGE_DESKTOP                                    0x1
  89# define INTEL_EDP_TCON_USAGE_FULL_SCREEN_MEDIA                          0x2
  90# define INTEL_EDP_TCON_USAGE_FULL_SCREEN_GAMING                         0x3
  91# define INTEL_EDP_TCON_POWER_MASK                                    BIT(4)
  92# define INTEL_EDP_TCON_POWER_DC                                    (0 << 4)
  93# define INTEL_EDP_TCON_POWER_AC                                    (1 << 4)
  94# define INTEL_EDP_TCON_OPTIMIZATION_STRENGTH_MASK             GENMASK(5, 7)
  95
  96#define INTEL_EDP_BRIGHTNESS_OPTIMIZATION_1                            0x359
  97
  98/* Intel EDP backlight callbacks */
  99static bool
 100intel_dp_aux_supports_hdr_backlight(struct intel_connector *connector)
 101{
 102        struct drm_i915_private *i915 = to_i915(connector->base.dev);
 103        struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
 104        struct drm_dp_aux *aux = &intel_dp->aux;
 105        struct intel_panel *panel = &connector->panel;
 106        int ret;
 107        u8 tcon_cap[4];
 108
 109        ret = drm_dp_dpcd_read(aux, INTEL_EDP_HDR_TCON_CAP0, tcon_cap, sizeof(tcon_cap));
 110        if (ret != sizeof(tcon_cap))
 111                return false;
 112
 113        if (!(tcon_cap[1] & INTEL_EDP_HDR_TCON_BRIGHTNESS_NITS_CAP))
 114                return false;
 115
 116        if (tcon_cap[0] >= 1) {
 117                drm_dbg_kms(&i915->drm, "Detected Intel HDR backlight interface version %d\n",
 118                            tcon_cap[0]);
 119        } else {
 120                drm_dbg_kms(&i915->drm, "Detected unsupported HDR backlight interface version %d\n",
 121                            tcon_cap[0]);
 122                return false;
 123        }
 124
 125        panel->backlight.edp.intel.sdr_uses_aux =
 126                tcon_cap[2] & INTEL_EDP_SDR_TCON_BRIGHTNESS_AUX_CAP;
 127
 128        return true;
 129}
 130
 131static u32
 132intel_dp_aux_hdr_get_backlight(struct intel_connector *connector, enum pipe pipe)
 133{
 134        struct drm_i915_private *i915 = to_i915(connector->base.dev);
 135        struct intel_panel *panel = &connector->panel;
 136        struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
 137        u8 tmp;
 138        u8 buf[2] = { 0 };
 139
 140        if (drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &tmp) != 1) {
 141                drm_err(&i915->drm, "Failed to read current backlight mode from DPCD\n");
 142                return 0;
 143        }
 144
 145        if (!(tmp & INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE)) {
 146                if (!panel->backlight.edp.intel.sdr_uses_aux) {
 147                        u32 pwm_level = panel->backlight.pwm_funcs->get(connector, pipe);
 148
 149                        return intel_panel_backlight_level_from_pwm(connector, pwm_level);
 150                }
 151
 152                /* Assume 100% brightness if backlight controls aren't enabled yet */
 153                return panel->backlight.max;
 154        }
 155
 156        if (drm_dp_dpcd_read(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf,
 157                             sizeof(buf)) != sizeof(buf)) {
 158                drm_err(&i915->drm, "Failed to read brightness from DPCD\n");
 159                return 0;
 160        }
 161
 162        return (buf[1] << 8 | buf[0]);
 163}
 164
 165static void
 166intel_dp_aux_hdr_set_aux_backlight(const struct drm_connector_state *conn_state, u32 level)
 167{
 168        struct intel_connector *connector = to_intel_connector(conn_state->connector);
 169        struct drm_device *dev = connector->base.dev;
 170        struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
 171        u8 buf[4] = { 0 };
 172
 173        buf[0] = level & 0xFF;
 174        buf[1] = (level & 0xFF00) >> 8;
 175
 176        if (drm_dp_dpcd_write(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf,
 177                              sizeof(buf)) != sizeof(buf))
 178                drm_err(dev, "Failed to write brightness level to DPCD\n");
 179}
 180
 181static void
 182intel_dp_aux_hdr_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 183{
 184        struct intel_connector *connector = to_intel_connector(conn_state->connector);
 185        struct intel_panel *panel = &connector->panel;
 186
 187        if (panel->backlight.edp.intel.sdr_uses_aux) {
 188                intel_dp_aux_hdr_set_aux_backlight(conn_state, level);
 189        } else {
 190                const u32 pwm_level = intel_panel_backlight_level_to_pwm(connector, level);
 191
 192                intel_panel_set_pwm_level(conn_state, pwm_level);
 193        }
 194}
 195
 196static void
 197intel_dp_aux_hdr_enable_backlight(const struct intel_crtc_state *crtc_state,
 198                                  const struct drm_connector_state *conn_state, u32 level)
 199{
 200        struct intel_connector *connector = to_intel_connector(conn_state->connector);
 201        struct intel_panel *panel = &connector->panel;
 202        struct drm_i915_private *i915 = to_i915(connector->base.dev);
 203        struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
 204        int ret;
 205        u8 old_ctrl, ctrl;
 206
 207        ret = drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &old_ctrl);
 208        if (ret != 1) {
 209                drm_err(&i915->drm, "Failed to read current backlight control mode: %d\n", ret);
 210                return;
 211        }
 212
 213        ctrl = old_ctrl;
 214        if (panel->backlight.edp.intel.sdr_uses_aux) {
 215                ctrl |= INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE;
 216                intel_dp_aux_hdr_set_aux_backlight(conn_state, level);
 217        } else {
 218                u32 pwm_level = intel_panel_backlight_level_to_pwm(connector, level);
 219
 220                panel->backlight.pwm_funcs->enable(crtc_state, conn_state, pwm_level);
 221
 222                ctrl &= ~INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE;
 223        }
 224
 225        if (ctrl != old_ctrl)
 226                if (drm_dp_dpcd_writeb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, ctrl) != 1)
 227                        drm_err(&i915->drm, "Failed to configure DPCD brightness controls\n");
 228}
 229
 230static void
 231intel_dp_aux_hdr_disable_backlight(const struct drm_connector_state *conn_state, u32 level)
 232{
 233        struct intel_connector *connector = to_intel_connector(conn_state->connector);
 234        struct intel_panel *panel = &connector->panel;
 235
 236        /* Nothing to do for AUX based backlight controls */
 237        if (panel->backlight.edp.intel.sdr_uses_aux)
 238                return;
 239
 240        /* Note we want the actual pwm_level to be 0, regardless of pwm_min */
 241        panel->backlight.pwm_funcs->disable(conn_state, intel_panel_invert_pwm_level(connector, 0));
 242}
 243
 244static int
 245intel_dp_aux_hdr_setup_backlight(struct intel_connector *connector, enum pipe pipe)
 246{
 247        struct drm_i915_private *i915 = to_i915(connector->base.dev);
 248        struct intel_panel *panel = &connector->panel;
 249        int ret;
 250
 251        if (panel->backlight.edp.intel.sdr_uses_aux) {
 252                drm_dbg_kms(&i915->drm, "SDR backlight is controlled through DPCD\n");
 253        } else {
 254                drm_dbg_kms(&i915->drm, "SDR backlight is controlled through PWM\n");
 255
 256                ret = panel->backlight.pwm_funcs->setup(connector, pipe);
 257                if (ret < 0) {
 258                        drm_err(&i915->drm,
 259                                "Failed to setup SDR backlight controls through PWM: %d\n", ret);
 260                        return ret;
 261                }
 262        }
 263
 264        panel->backlight.max = 512;
 265        panel->backlight.min = 0;
 266        panel->backlight.level = intel_dp_aux_hdr_get_backlight(connector, pipe);
 267        panel->backlight.enabled = panel->backlight.level != 0;
 268
 269        return 0;
 270}
 271
 272/* VESA backlight callbacks */
 273static u32 intel_dp_aux_vesa_get_backlight(struct intel_connector *connector, enum pipe unused)
 274{
 275        return connector->panel.backlight.level;
 276}
 277
 278static void
 279intel_dp_aux_vesa_set_backlight(const struct drm_connector_state *conn_state, u32 level)
 280{
 281        struct intel_connector *connector = to_intel_connector(conn_state->connector);
 282        struct intel_panel *panel = &connector->panel;
 283        struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
 284
 285        drm_edp_backlight_set_level(&intel_dp->aux, &panel->backlight.edp.vesa.info, level);
 286}
 287
 288static void
 289intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state,
 290                                   const struct drm_connector_state *conn_state, u32 level)
 291{
 292        struct intel_connector *connector = to_intel_connector(conn_state->connector);
 293        struct intel_panel *panel = &connector->panel;
 294        struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
 295
 296        drm_edp_backlight_enable(&intel_dp->aux, &panel->backlight.edp.vesa.info, level);
 297}
 298
 299static void intel_dp_aux_vesa_disable_backlight(const struct drm_connector_state *old_conn_state,
 300                                                u32 level)
 301{
 302        struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
 303        struct intel_panel *panel = &connector->panel;
 304        struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
 305
 306        drm_edp_backlight_disable(&intel_dp->aux, &panel->backlight.edp.vesa.info);
 307}
 308
 309static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector, enum pipe pipe)
 310{
 311        struct intel_dp *intel_dp = intel_attached_dp(connector);
 312        struct intel_panel *panel = &connector->panel;
 313        struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 314        u16 current_level;
 315        u8 current_mode;
 316        int ret;
 317
 318        ret = drm_edp_backlight_init(&intel_dp->aux, &panel->backlight.edp.vesa.info,
 319                                     i915->vbt.backlight.pwm_freq_hz, intel_dp->edp_dpcd,
 320                                     &current_level, &current_mode);
 321        if (ret < 0)
 322                return ret;
 323
 324        panel->backlight.max = panel->backlight.edp.vesa.info.max;
 325        panel->backlight.min = 0;
 326        if (current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) {
 327                panel->backlight.level = current_level;
 328                panel->backlight.enabled = panel->backlight.level != 0;
 329        } else {
 330                panel->backlight.level = panel->backlight.max;
 331                panel->backlight.enabled = false;
 332        }
 333
 334        return 0;
 335}
 336
 337static bool
 338intel_dp_aux_supports_vesa_backlight(struct intel_connector *connector)
 339{
 340        struct intel_dp *intel_dp = intel_attached_dp(connector);
 341        struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 342
 343        /* TODO: We currently only support AUX only backlight configurations, not backlights which
 344         * require a mix of PWM and AUX controls to work. In the mean time, these machines typically
 345         * work just fine using normal PWM controls anyway.
 346         */
 347        if ((intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) &&
 348            drm_edp_backlight_supported(intel_dp->edp_dpcd)) {
 349                drm_dbg_kms(&i915->drm, "AUX Backlight Control Supported!\n");
 350                return true;
 351        }
 352        return false;
 353}
 354
 355static const struct intel_panel_bl_funcs intel_dp_hdr_bl_funcs = {
 356        .setup = intel_dp_aux_hdr_setup_backlight,
 357        .enable = intel_dp_aux_hdr_enable_backlight,
 358        .disable = intel_dp_aux_hdr_disable_backlight,
 359        .set = intel_dp_aux_hdr_set_backlight,
 360        .get = intel_dp_aux_hdr_get_backlight,
 361};
 362
 363static const struct intel_panel_bl_funcs intel_dp_vesa_bl_funcs = {
 364        .setup = intel_dp_aux_vesa_setup_backlight,
 365        .enable = intel_dp_aux_vesa_enable_backlight,
 366        .disable = intel_dp_aux_vesa_disable_backlight,
 367        .set = intel_dp_aux_vesa_set_backlight,
 368        .get = intel_dp_aux_vesa_get_backlight,
 369};
 370
 371enum intel_dp_aux_backlight_modparam {
 372        INTEL_DP_AUX_BACKLIGHT_AUTO = -1,
 373        INTEL_DP_AUX_BACKLIGHT_OFF = 0,
 374        INTEL_DP_AUX_BACKLIGHT_ON = 1,
 375        INTEL_DP_AUX_BACKLIGHT_FORCE_VESA = 2,
 376        INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL = 3,
 377};
 378
 379int intel_dp_aux_init_backlight_funcs(struct intel_connector *connector)
 380{
 381        struct drm_device *dev = connector->base.dev;
 382        struct intel_panel *panel = &connector->panel;
 383        struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
 384        struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 385        bool try_intel_interface = false, try_vesa_interface = false;
 386
 387        /* Check the VBT and user's module parameters to figure out which
 388         * interfaces to probe
 389         */
 390        switch (i915->params.enable_dpcd_backlight) {
 391        case INTEL_DP_AUX_BACKLIGHT_OFF:
 392                return -ENODEV;
 393        case INTEL_DP_AUX_BACKLIGHT_AUTO:
 394                switch (i915->vbt.backlight.type) {
 395                case INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE:
 396                        try_vesa_interface = true;
 397                        break;
 398                case INTEL_BACKLIGHT_DISPLAY_DDI:
 399                        try_intel_interface = true;
 400                        break;
 401                default:
 402                        return -ENODEV;
 403                }
 404                break;
 405        case INTEL_DP_AUX_BACKLIGHT_ON:
 406                if (i915->vbt.backlight.type != INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE)
 407                        try_intel_interface = true;
 408
 409                try_vesa_interface = true;
 410                break;
 411        case INTEL_DP_AUX_BACKLIGHT_FORCE_VESA:
 412                try_vesa_interface = true;
 413                break;
 414        case INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL:
 415                try_intel_interface = true;
 416                break;
 417        }
 418
 419        /*
 420         * A lot of eDP panels in the wild will report supporting both the
 421         * Intel proprietary backlight control interface, and the VESA
 422         * backlight control interface. Many of these panels are liars though,
 423         * and will only work with the Intel interface. So, always probe for
 424         * that first.
 425         */
 426        if (try_intel_interface && intel_dp_aux_supports_hdr_backlight(connector)) {
 427                drm_dbg_kms(dev, "Using Intel proprietary eDP backlight controls\n");
 428                panel->backlight.funcs = &intel_dp_hdr_bl_funcs;
 429                return 0;
 430        }
 431
 432        if (try_vesa_interface && intel_dp_aux_supports_vesa_backlight(connector)) {
 433                drm_dbg_kms(dev, "Using VESA eDP backlight controls\n");
 434                panel->backlight.funcs = &intel_dp_vesa_bl_funcs;
 435                return 0;
 436        }
 437
 438        return -ENODEV;
 439}
 440