diff options
Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c')
-rw-r--r-- | drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 549 |
1 files changed, 549 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c new file mode 100644 index 0000000000..95cc525184 --- /dev/null +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -0,0 +1,549 @@ +/* + * Copyright © 2015 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + * + */ + +/* + * Laptops with Intel GPUs which have panels that support controlling the + * backlight through DP AUX can actually use two different interfaces: Intel's + * proprietary DP AUX backlight interface, and the standard VESA backlight + * interface. Unfortunately, at the time of writing this a lot of laptops will + * advertise support for the standard VESA backlight interface when they + * don't properly support it. However, on these systems the Intel backlight + * interface generally does work properly. Additionally, these systems will + * usually just indicate that they use PWM backlight controls in their VBIOS + * for some reason. + */ + +#include "i915_drv.h" +#include "intel_backlight.h" +#include "intel_display_types.h" +#include "intel_dp.h" +#include "intel_dp_aux_backlight.h" + +/* TODO: + * Implement HDR, right now we just implement the bare minimum to bring us back into SDR mode so we + * can make people's backlights work in the mean time + */ + +/* + * DP AUX registers for Intel's proprietary HDR backlight interface. We define + * them here since we'll likely be the only driver to ever use these. + */ +#define INTEL_EDP_HDR_TCON_CAP0 0x340 + +#define INTEL_EDP_HDR_TCON_CAP1 0x341 +# define INTEL_EDP_HDR_TCON_2084_DECODE_CAP BIT(0) +# define INTEL_EDP_HDR_TCON_2020_GAMUT_CAP BIT(1) +# define INTEL_EDP_HDR_TCON_TONE_MAPPING_CAP BIT(2) +# define INTEL_EDP_HDR_TCON_SEGMENTED_BACKLIGHT_CAP BIT(3) +# define INTEL_EDP_HDR_TCON_BRIGHTNESS_NITS_CAP BIT(4) +# define INTEL_EDP_HDR_TCON_OPTIMIZATION_CAP BIT(5) +# define INTEL_EDP_HDR_TCON_SDP_COLORIMETRY_CAP BIT(6) +# define INTEL_EDP_HDR_TCON_SRGB_TO_PANEL_GAMUT_CONVERSION_CAP BIT(7) + +#define INTEL_EDP_HDR_TCON_CAP2 0x342 +# define INTEL_EDP_SDR_TCON_BRIGHTNESS_AUX_CAP BIT(0) + +#define INTEL_EDP_HDR_TCON_CAP3 0x343 + +#define INTEL_EDP_HDR_GETSET_CTRL_PARAMS 0x344 +# define INTEL_EDP_HDR_TCON_2084_DECODE_ENABLE BIT(0) +# define INTEL_EDP_HDR_TCON_2020_GAMUT_ENABLE BIT(1) +# define INTEL_EDP_HDR_TCON_TONE_MAPPING_ENABLE BIT(2) /* Pre-TGL+ */ +# define INTEL_EDP_HDR_TCON_SEGMENTED_BACKLIGHT_ENABLE BIT(3) +# define INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE BIT(4) +# define INTEL_EDP_HDR_TCON_SRGB_TO_PANEL_GAMUT_ENABLE BIT(5) +/* Bit 6 is reserved */ +# define INTEL_EDP_HDR_TCON_SDP_COLORIMETRY_ENABLE BIT(7) + +#define INTEL_EDP_HDR_CONTENT_LUMINANCE 0x346 /* Pre-TGL+ */ +#define INTEL_EDP_HDR_PANEL_LUMINANCE_OVERRIDE 0x34A +#define INTEL_EDP_SDR_LUMINANCE_LEVEL 0x352 +#define INTEL_EDP_BRIGHTNESS_NITS_LSB 0x354 +#define INTEL_EDP_BRIGHTNESS_NITS_MSB 0x355 +#define INTEL_EDP_BRIGHTNESS_DELAY_FRAMES 0x356 +#define INTEL_EDP_BRIGHTNESS_PER_FRAME_STEPS 0x357 + +#define INTEL_EDP_BRIGHTNESS_OPTIMIZATION_0 0x358 +# define INTEL_EDP_TCON_USAGE_MASK GENMASK(0, 3) +# define INTEL_EDP_TCON_USAGE_UNKNOWN 0x0 +# define INTEL_EDP_TCON_USAGE_DESKTOP 0x1 +# define INTEL_EDP_TCON_USAGE_FULL_SCREEN_MEDIA 0x2 +# define INTEL_EDP_TCON_USAGE_FULL_SCREEN_GAMING 0x3 +# define INTEL_EDP_TCON_POWER_MASK BIT(4) +# define INTEL_EDP_TCON_POWER_DC (0 << 4) +# define INTEL_EDP_TCON_POWER_AC (1 << 4) +# define INTEL_EDP_TCON_OPTIMIZATION_STRENGTH_MASK GENMASK(5, 7) + +#define INTEL_EDP_BRIGHTNESS_OPTIMIZATION_1 0x359 + +enum intel_dp_aux_backlight_modparam { + INTEL_DP_AUX_BACKLIGHT_AUTO = -1, + INTEL_DP_AUX_BACKLIGHT_OFF = 0, + INTEL_DP_AUX_BACKLIGHT_ON = 1, + INTEL_DP_AUX_BACKLIGHT_FORCE_VESA = 2, + INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL = 3, +}; + +static bool is_intel_tcon_cap(const u8 tcon_cap[4]) +{ + return tcon_cap[0] >= 1; +} + +/* Intel EDP backlight callbacks */ +static bool +intel_dp_aux_supports_hdr_backlight(struct intel_connector *connector) +{ + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + struct drm_dp_aux *aux = &intel_dp->aux; + struct intel_panel *panel = &connector->panel; + int ret; + u8 tcon_cap[4]; + + intel_dp_wait_source_oui(intel_dp); + + ret = drm_dp_dpcd_read(aux, INTEL_EDP_HDR_TCON_CAP0, tcon_cap, sizeof(tcon_cap)); + if (ret != sizeof(tcon_cap)) + return false; + + if (!(tcon_cap[1] & INTEL_EDP_HDR_TCON_BRIGHTNESS_NITS_CAP)) + return false; + + drm_dbg_kms(&i915->drm, "[CONNECTOR:%d:%s] Detected %s HDR backlight interface version %d\n", + connector->base.base.id, connector->base.name, + is_intel_tcon_cap(tcon_cap) ? "Intel" : "unsupported", tcon_cap[0]); + + if (!is_intel_tcon_cap(tcon_cap)) + return false; + + /* + * If we don't have HDR static metadata there is no way to + * runtime detect used range for nits based control. For now + * do not use Intel proprietary eDP backlight control if we + * don't have this data in panel EDID. In case we find panel + * which supports only nits based control, but doesn't provide + * HDR static metadata we need to start maintaining table of + * ranges for such panels. + */ + if (i915->params.enable_dpcd_backlight != INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL && + !(connector->base.hdr_sink_metadata.hdmi_type1.metadata_type & + BIT(HDMI_STATIC_METADATA_TYPE1))) { + drm_info(&i915->drm, + "[CONNECTOR:%d:%s] Panel is missing HDR static metadata. Possible support for Intel HDR backlight interface is not used. If your backlight controls don't work try booting with i915.enable_dpcd_backlight=%d. needs this, please file a _new_ bug report on drm/i915, see " FDO_BUG_URL " for details.\n", + connector->base.base.id, connector->base.name, + INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL); + return false; + } + + panel->backlight.edp.intel.sdr_uses_aux = + tcon_cap[2] & INTEL_EDP_SDR_TCON_BRIGHTNESS_AUX_CAP; + + return true; +} + +static u32 +intel_dp_aux_hdr_get_backlight(struct intel_connector *connector, enum pipe pipe) +{ + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_panel *panel = &connector->panel; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + u8 tmp; + u8 buf[2] = { 0 }; + + if (drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &tmp) != 1) { + drm_err(&i915->drm, "[CONNECTOR:%d:%s] Failed to read current backlight mode from DPCD\n", + connector->base.base.id, connector->base.name); + return 0; + } + + if (!(tmp & INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE)) { + if (!panel->backlight.edp.intel.sdr_uses_aux) { + u32 pwm_level = panel->backlight.pwm_funcs->get(connector, pipe); + + return intel_backlight_level_from_pwm(connector, pwm_level); + } + + /* Assume 100% brightness if backlight controls aren't enabled yet */ + return panel->backlight.max; + } + + if (drm_dp_dpcd_read(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf, + sizeof(buf)) != sizeof(buf)) { + drm_err(&i915->drm, "[CONNECTOR:%d:%s] Failed to read brightness from DPCD\n", + connector->base.base.id, connector->base.name); + return 0; + } + + return (buf[1] << 8 | buf[0]); +} + +static void +intel_dp_aux_hdr_set_aux_backlight(const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct drm_device *dev = connector->base.dev; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + u8 buf[4] = { 0 }; + + buf[0] = level & 0xFF; + buf[1] = (level & 0xFF00) >> 8; + + if (drm_dp_dpcd_write(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf, + sizeof(buf)) != sizeof(buf)) + drm_err(dev, "[CONNECTOR:%d:%s] Failed to write brightness level to DPCD\n", + connector->base.base.id, connector->base.name); +} + +static void +intel_dp_aux_hdr_set_backlight(const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + + if (panel->backlight.edp.intel.sdr_uses_aux) { + intel_dp_aux_hdr_set_aux_backlight(conn_state, level); + } else { + const u32 pwm_level = intel_backlight_level_to_pwm(connector, level); + + intel_backlight_set_pwm_level(conn_state, pwm_level); + } +} + +static void +intel_dp_aux_hdr_enable_backlight(const struct intel_crtc_state *crtc_state, + const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + int ret; + u8 old_ctrl, ctrl; + + intel_dp_wait_source_oui(intel_dp); + + ret = drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &old_ctrl); + if (ret != 1) { + drm_err(&i915->drm, "[CONNECTOR:%d:%s] Failed to read current backlight control mode: %d\n", + connector->base.base.id, connector->base.name, ret); + return; + } + + ctrl = old_ctrl; + if (panel->backlight.edp.intel.sdr_uses_aux) { + ctrl |= INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE; + intel_dp_aux_hdr_set_aux_backlight(conn_state, level); + } else { + u32 pwm_level = intel_backlight_level_to_pwm(connector, level); + + panel->backlight.pwm_funcs->enable(crtc_state, conn_state, pwm_level); + + ctrl &= ~INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE; + } + + if (ctrl != old_ctrl && + drm_dp_dpcd_writeb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, ctrl) != 1) + drm_err(&i915->drm, "[CONNECTOR:%d:%s] Failed to configure DPCD brightness controls\n", + connector->base.base.id, connector->base.name); +} + +static void +intel_dp_aux_hdr_disable_backlight(const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + + /* Nothing to do for AUX based backlight controls */ + if (panel->backlight.edp.intel.sdr_uses_aux) + return; + + /* Note we want the actual pwm_level to be 0, regardless of pwm_min */ + panel->backlight.pwm_funcs->disable(conn_state, intel_backlight_invert_pwm_level(connector, 0)); +} + +static const char *dpcd_vs_pwm_str(bool aux) +{ + return aux ? "DPCD" : "PWM"; +} + +static int +intel_dp_aux_hdr_setup_backlight(struct intel_connector *connector, enum pipe pipe) +{ + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_panel *panel = &connector->panel; + struct drm_luminance_range_info *luminance_range = + &connector->base.display_info.luminance_range; + int ret; + + drm_dbg_kms(&i915->drm, "[CONNECTOR:%d:%s] SDR backlight is controlled through %s\n", + connector->base.base.id, connector->base.name, + dpcd_vs_pwm_str(panel->backlight.edp.intel.sdr_uses_aux)); + + if (!panel->backlight.edp.intel.sdr_uses_aux) { + ret = panel->backlight.pwm_funcs->setup(connector, pipe); + if (ret < 0) { + drm_err(&i915->drm, + "[CONNECTOR:%d:%s] Failed to setup SDR backlight controls through PWM: %d\n", + connector->base.base.id, connector->base.name, ret); + return ret; + } + } + + if (luminance_range->max_luminance) { + panel->backlight.max = luminance_range->max_luminance; + panel->backlight.min = luminance_range->min_luminance; + } else { + panel->backlight.max = 512; + panel->backlight.min = 0; + } + + drm_dbg_kms(&i915->drm, "[CONNECTOR:%d:%s] Using AUX HDR interface for backlight control (range %d..%d)\n", + connector->base.base.id, connector->base.name, + panel->backlight.min, panel->backlight.max); + + + panel->backlight.level = intel_dp_aux_hdr_get_backlight(connector, pipe); + panel->backlight.enabled = panel->backlight.level != 0; + + return 0; +} + +/* VESA backlight callbacks */ +static u32 intel_dp_aux_vesa_get_backlight(struct intel_connector *connector, enum pipe unused) +{ + return connector->panel.backlight.level; +} + +static void +intel_dp_aux_vesa_set_backlight(const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + + if (!panel->backlight.edp.vesa.info.aux_set) { + const u32 pwm_level = intel_backlight_level_to_pwm(connector, level); + + intel_backlight_set_pwm_level(conn_state, pwm_level); + } + + drm_edp_backlight_set_level(&intel_dp->aux, &panel->backlight.edp.vesa.info, level); +} + +static void +intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state, + const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + + if (!panel->backlight.edp.vesa.info.aux_enable) { + u32 pwm_level; + + if (!panel->backlight.edp.vesa.info.aux_set) + pwm_level = intel_backlight_level_to_pwm(connector, level); + else + pwm_level = intel_backlight_invert_pwm_level(connector, + panel->backlight.pwm_level_max); + + panel->backlight.pwm_funcs->enable(crtc_state, conn_state, pwm_level); + } + + drm_edp_backlight_enable(&intel_dp->aux, &panel->backlight.edp.vesa.info, level); +} + +static void intel_dp_aux_vesa_disable_backlight(const struct drm_connector_state *old_conn_state, + u32 level) +{ + struct intel_connector *connector = to_intel_connector(old_conn_state->connector); + struct intel_panel *panel = &connector->panel; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + + drm_edp_backlight_disable(&intel_dp->aux, &panel->backlight.edp.vesa.info); + + if (!panel->backlight.edp.vesa.info.aux_enable) + panel->backlight.pwm_funcs->disable(old_conn_state, + intel_backlight_invert_pwm_level(connector, 0)); +} + +static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector, enum pipe pipe) +{ + struct intel_dp *intel_dp = intel_attached_dp(connector); + struct intel_panel *panel = &connector->panel; + struct drm_i915_private *i915 = dp_to_i915(intel_dp); + u16 current_level; + u8 current_mode; + int ret; + + ret = drm_edp_backlight_init(&intel_dp->aux, &panel->backlight.edp.vesa.info, + panel->vbt.backlight.pwm_freq_hz, intel_dp->edp_dpcd, + ¤t_level, ¤t_mode); + if (ret < 0) + return ret; + + drm_dbg_kms(&i915->drm, "[CONNECTOR:%d:%s] AUX VESA backlight enable is controlled through %s\n", + connector->base.base.id, connector->base.name, + dpcd_vs_pwm_str(panel->backlight.edp.vesa.info.aux_enable)); + drm_dbg_kms(&i915->drm, "[CONNECTOR:%d:%s] AUX VESA backlight level is controlled through %s\n", + connector->base.base.id, connector->base.name, + dpcd_vs_pwm_str(panel->backlight.edp.vesa.info.aux_set)); + + if (!panel->backlight.edp.vesa.info.aux_set || !panel->backlight.edp.vesa.info.aux_enable) { + ret = panel->backlight.pwm_funcs->setup(connector, pipe); + if (ret < 0) { + drm_err(&i915->drm, + "[CONNECTOR:%d:%s] Failed to setup PWM backlight controls for eDP backlight: %d\n", + connector->base.base.id, connector->base.name, ret); + return ret; + } + } + + if (panel->backlight.edp.vesa.info.aux_set) { + panel->backlight.max = panel->backlight.edp.vesa.info.max; + panel->backlight.min = 0; + if (current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) { + panel->backlight.level = current_level; + panel->backlight.enabled = panel->backlight.level != 0; + } else { + panel->backlight.level = panel->backlight.max; + panel->backlight.enabled = false; + } + } else { + panel->backlight.max = panel->backlight.pwm_level_max; + panel->backlight.min = panel->backlight.pwm_level_min; + if (current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_PWM) { + panel->backlight.level = panel->backlight.pwm_funcs->get(connector, pipe); + panel->backlight.enabled = panel->backlight.pwm_enabled; + } else { + panel->backlight.level = panel->backlight.max; + panel->backlight.enabled = false; + } + } + + drm_dbg_kms(&i915->drm, "[CONNECTOR:%d:%s] Using AUX VESA interface for backlight control\n", + connector->base.base.id, connector->base.name); + + return 0; +} + +static bool +intel_dp_aux_supports_vesa_backlight(struct intel_connector *connector) +{ + struct intel_dp *intel_dp = intel_attached_dp(connector); + struct drm_i915_private *i915 = dp_to_i915(intel_dp); + + if (drm_edp_backlight_supported(intel_dp->edp_dpcd)) { + drm_dbg_kms(&i915->drm, "[CONNECTOR:%d:%s] AUX Backlight Control Supported!\n", + connector->base.base.id, connector->base.name); + return true; + } + return false; +} + +static const struct intel_panel_bl_funcs intel_dp_hdr_bl_funcs = { + .setup = intel_dp_aux_hdr_setup_backlight, + .enable = intel_dp_aux_hdr_enable_backlight, + .disable = intel_dp_aux_hdr_disable_backlight, + .set = intel_dp_aux_hdr_set_backlight, + .get = intel_dp_aux_hdr_get_backlight, +}; + +static const struct intel_panel_bl_funcs intel_dp_vesa_bl_funcs = { + .setup = intel_dp_aux_vesa_setup_backlight, + .enable = intel_dp_aux_vesa_enable_backlight, + .disable = intel_dp_aux_vesa_disable_backlight, + .set = intel_dp_aux_vesa_set_backlight, + .get = intel_dp_aux_vesa_get_backlight, +}; + +int intel_dp_aux_init_backlight_funcs(struct intel_connector *connector) +{ + struct drm_device *dev = connector->base.dev; + struct intel_panel *panel = &connector->panel; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + struct drm_i915_private *i915 = dp_to_i915(intel_dp); + bool try_intel_interface = false, try_vesa_interface = false; + + /* Check the VBT and user's module parameters to figure out which + * interfaces to probe + */ + switch (i915->params.enable_dpcd_backlight) { + case INTEL_DP_AUX_BACKLIGHT_OFF: + return -ENODEV; + case INTEL_DP_AUX_BACKLIGHT_AUTO: + switch (panel->vbt.backlight.type) { + case INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE: + try_vesa_interface = true; + break; + case INTEL_BACKLIGHT_DISPLAY_DDI: + try_intel_interface = true; + break; + default: + return -ENODEV; + } + break; + case INTEL_DP_AUX_BACKLIGHT_ON: + if (panel->vbt.backlight.type != INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE) + try_intel_interface = true; + + try_vesa_interface = true; + break; + case INTEL_DP_AUX_BACKLIGHT_FORCE_VESA: + try_vesa_interface = true; + break; + case INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL: + try_intel_interface = true; + break; + } + + /* + * Since Intel has their own backlight control interface, the majority of machines out there + * using DPCD backlight controls with Intel GPUs will be using this interface as opposed to + * the VESA interface. However, other GPUs (such as Nvidia's) will always use the VESA + * interface. This means that there's quite a number of panels out there that will advertise + * support for both interfaces, primarily systems with Intel/Nvidia hybrid GPU setups. + * + * There's a catch to this though: on many panels that advertise support for both + * interfaces, the VESA backlight interface will stop working once we've programmed the + * panel with Intel's OUI - which is also required for us to be able to detect Intel's + * backlight interface at all. This means that the only sensible way for us to detect both + * interfaces is to probe for Intel's first, and VESA's second. + */ + if (try_intel_interface && intel_dp_aux_supports_hdr_backlight(connector)) { + drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Using Intel proprietary eDP backlight controls\n", + connector->base.base.id, connector->base.name); + panel->backlight.funcs = &intel_dp_hdr_bl_funcs; + return 0; + } + + if (try_vesa_interface && intel_dp_aux_supports_vesa_backlight(connector)) { + drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Using VESA eDP backlight controls\n", + connector->base.base.id, connector->base.name); + panel->backlight.funcs = &intel_dp_vesa_bl_funcs; + return 0; + } + + return -ENODEV; +} |