From 904a2b4014ea38c67b6bd19de12c27a2d5f7a6b1 Mon Sep 17 00:00:00 2001 From: Lyude Paul Date: Mon, 29 Jun 2020 15:01:49 -0400 Subject: [PATCH 2/2] WIP: drm/i915: Enable Intel's HDR backlight interface (only SDR for now) So-recently a bunch of laptops on the market have started using DPCD backlight controls instead of the traditional DDI backlight controls. Originally we thought we had this handled by adding VESA backlight control support to i915, but the story ended up being a lot more complicated then that. Simply put-there's two main backlight interfaces Intel can see in the wild. Intel's proprietary HDR backlight interface, and the standard VESA backlight interface. Note that many panels have been observed to report support for both backlight interfaces, but testing has shown far more panels work with the Intel HDR backlight interface at the moment. Additionally, the VBT appears to be capable of reporting support for the VESA backlight interface but not the Intel HDR interface which needs to be probed by setting the right magic OUI. For the time being we've been using EDIDs to maintain a list of quirks for panels that safely do support the VESA backlight interface. Adding support for Intel's HDR backlight interface in addition however, should finally allow us to auto-detect eDP backlight controls properly so long as we probe like so: * If the panel's VBT reports VESA backlight support, assume it really does support it * If the panel's VBT reports DDI backlight controls: * First probe for Intel's HDR backlight interface * If that fails, probe for VESA's backlight interface * If that fails, assume no DPCD backlight control * If the panel's VBT reports any other backlight type: just assume it doesn't have DPCD backlight controls Note as well that in order for us to make Intel's HDR backlight interface appear, we need to start programming the appropriate source OUI on the eDP panel as early as possible in the probing process. Note that this technically could be done at any time before setting up backlight controls, but this way allows us to avoid re-writing it multiple times in case we need to use other source-OUI enabled features in the future. Finally, we also make sure to document the registers for this backlight interface since eventually, we want to actually implement the full interface instead of keeping it in SDR mode. Signed-off-by: Lyude Paul --- .../drm/i915/display/intel_display_types.h | 9 +- drivers/gpu/drm/i915/display/intel_dp.c | 15 + .../drm/i915/display/intel_dp_aux_backlight.c | 334 +++++++++++++++--- drivers/gpu/drm/i915/i915_params.c | 2 +- 4 files changed, 308 insertions(+), 52 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index 5e00e611f077..b89e67e271ed 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -219,7 +219,14 @@ struct intel_panel { struct pwm_device *pwm; /* DPCD backlight */ - u8 pwmgen_bit_count; + union { + struct { + u8 pwmgen_bit_count; + } vesa; + struct { + + } intel; + } edp; struct backlight_device *device; diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 9231a0ef6270..5a66cf5caefe 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -3201,7 +3201,10 @@ void intel_dp_sink_set_decompression_state(struct intel_dp *intel_dp, /* If the sink supports it, try to set the power state appropriately */ void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode) { + struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp); + struct drm_i915_private *dev_priv = to_i915(intel_dig_port->base.base.dev); int ret, i; + u8 edp_oui[] = { 0x00, 0xaa, 0x01 }; /* Should have a valid DPCD by this point */ if (intel_dp->dpcd[DP_DPCD_REV] < 0x11) @@ -3216,6 +3219,16 @@ void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode) } else { struct intel_lspcon *lspcon = dp_to_lspcon(intel_dp); + /* Write the source OUI as early as possible */ + if (intel_dp_is_edp(intel_dp)) { + ret = drm_dp_dpcd_write(&intel_dp->aux, + DP_SOURCE_OUI, edp_oui, + sizeof(edp_oui)); + if (ret < 0) + drm_err(&dev_priv->drm, + "Failed to write eDP source OUI\n"); + } + /* * When turning on, we need to retry for 1ms to give the sink * time to wake up. @@ -4408,6 +4421,8 @@ static void intel_dp_get_dsc_sink_cap(struct intel_dp *intel_dp) } } + + static void intel_edp_init_source_oui(struct intel_dp *intel_dp) { diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c index dbfa6895795b..9d43003760fd 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -22,10 +22,196 @@ * */ +/* XXX: maybe make this kernel docs */ +/* + * 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 "intel_display_types.h" #include "intel_dp_aux_backlight.h" -static void set_aux_backlight_enable(struct intel_dp *intel_dp, bool enable) +/* + * 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 + +/* Intel EDP backlight callbacks */ +static bool +intel_dp_aux_supports_hdr_backlight(struct intel_connector *connector) +{ + struct drm_device *dev = connector->base.dev; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + struct drm_dp_aux *aux = &intel_dp->aux; + int ret; + u8 tcon_cap[4]; + + ret = drm_dp_dpcd_read(aux, INTEL_EDP_HDR_TCON_CAP0, + tcon_cap, sizeof(tcon_cap)); + if (ret < 0) + return false; + + if (!(tcon_cap[1] & INTEL_EDP_HDR_TCON_BRIGHTNESS_NITS_CAP)) + return false; + + /* TODO: Add support for AUX backlight controls in HDR mode */ + if (!(tcon_cap[2] & INTEL_EDP_SDR_TCON_BRIGHTNESS_AUX_CAP)) { + DRM_DEV_DEBUG_KMS(dev->dev, + "Panel only supports AUX backlight controls for HDR mode, this isn't implemented yet\n"); + return false; + } + + return true; +} + +static u32 +intel_dp_aux_hdr_get_backlight(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); + u8 tmp; + u8 buf[2] = { 0 }; + + if (drm_dp_dpcd_readb(&intel_dp->aux, + INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &tmp) < 0) + DRM_DEV_DEBUG_KMS(dev->dev, + "Failed to read current backlight mode from DPCD\n"); + + /* Assume 100% brightness if backlight controls aren't enabled over + * AUX yet + */ + if (!(tmp & INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE)) + return panel->backlight.max; + + if (drm_dp_dpcd_read(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, + buf, sizeof(buf)) < 0) { + DRM_DEV_DEBUG_KMS(dev->dev, + "Failed to read brightness from DPCD\n"); + return 0; + } + + return (buf[1] << 8 | buf[0]); +} + +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 drm_device *dev = connector->base.dev; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + uint8_t 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, 4) < 0) + DRM_DEV_DEBUG_KMS(dev->dev, + "Failed to write brightness level to DPCD\n"); +} + +static void +intel_dp_aux_hdr_enable_backlight(const struct intel_crtc_state *crtc_state, + const struct drm_connector_state *conn_state) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + struct drm_device *dev = connector->base.dev; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + + /* FIXME: figure out if we really need to clear the register + * beforehand, ideally we want to avoid turning the backlight off when + * it's not needed + */ + if (drm_dp_dpcd_writeb(&intel_dp->aux, + INTEL_EDP_HDR_GETSET_CTRL_PARAMS, + INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE) < 0) + drm_err(dev, "Failed to enable AUX brightness control\n"); + + intel_dp_aux_hdr_set_backlight(conn_state, panel->backlight.level); + /* FIXME: do we need to write the brightness level before or after we + * enable the relevant brightness modes? + */ +} + +static void +intel_dp_aux_hdr_disable_backlight(const struct drm_connector_state *old_conn_state) +{ + /* no-op */ +} + +static int +intel_dp_aux_hdr_setup_backlight(struct intel_connector *connector, + enum pipe pipe) +{ + struct intel_panel *panel = &connector->panel; + + panel->backlight.max = 512; + panel->backlight.min = 0; + panel->backlight.level = intel_dp_aux_hdr_get_backlight(connector); + panel->backlight.enabled = panel->backlight.level != 0; + + return 0; +} + +/* VESA backlight callbacks */ +static void set_vesa_backlight_enable(struct intel_dp *intel_dp, bool enable) { u8 reg_val = 0; @@ -55,7 +241,7 @@ static void set_aux_backlight_enable(struct intel_dp *intel_dp, bool enable) * Read the current backlight value from DPCD register(s) based * on if 8-bit(MSB) or 16-bit(MSB and LSB) values are supported */ -static u32 intel_dp_aux_get_backlight(struct intel_connector *connector) +static u32 intel_dp_aux_vesa_get_backlight(struct intel_connector *connector) { struct intel_dp *intel_dp = intel_attached_dp(connector); u8 read_val[2] = { 0x0 }; @@ -96,7 +282,7 @@ static u32 intel_dp_aux_get_backlight(struct intel_connector *connector) * 8-bit or 16 bit value (MSB and LSB) */ static void -intel_dp_aux_set_backlight(const struct drm_connector_state *conn_state, u32 level) +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_dp *intel_dp = intel_attached_dp(connector); @@ -124,11 +310,11 @@ intel_dp_aux_set_backlight(const struct drm_connector_state *conn_state, u32 lev * - Where P = 2^Pn, where Pn is the value programmed by field 4:0 of the * EDP_PWMGEN_BIT_COUNT register (DPCD Address 00724h) */ -static bool intel_dp_aux_set_pwm_freq(struct intel_connector *connector) +static bool intel_dp_aux_vesa_set_pwm_freq(struct intel_connector *connector) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); struct intel_dp *intel_dp = intel_attached_dp(connector); - const u8 pn = connector->panel.backlight.pwmgen_bit_count; + const u8 pn = connector->panel.backlight.edp.vesa.pwmgen_bit_count; int freq, fxp, f, fxp_actual, fxp_min, fxp_max; freq = dev_priv->vbt.backlight.pwm_freq_hz; @@ -158,13 +344,14 @@ static bool intel_dp_aux_set_pwm_freq(struct intel_connector *connector) return true; } -static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_state, - const struct drm_connector_state *conn_state) +static void intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state, + const struct drm_connector_state *conn_state) { struct intel_connector *connector = to_intel_connector(conn_state->connector); struct intel_dp *intel_dp = intel_attached_dp(connector); struct intel_panel *panel = &connector->panel; u8 dpcd_buf, new_dpcd_buf, edp_backlight_mode; + u8 pwmgen_bit_count = panel->backlight.edp.vesa.pwmgen_bit_count; if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &dpcd_buf) != 1) { @@ -185,7 +372,7 @@ static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_st if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, - panel->backlight.pwmgen_bit_count) < 0) + pwmgen_bit_count) < 0) DRM_DEBUG_KMS("Failed to write aux pwmgen bit count\n"); break; @@ -197,7 +384,7 @@ static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_st } if (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_FREQ_AUX_SET_CAP) - if (intel_dp_aux_set_pwm_freq(connector)) + if (intel_dp_aux_vesa_set_pwm_freq(connector)) new_dpcd_buf |= DP_EDP_BACKLIGHT_FREQ_AUX_SET_ENABLE; if (new_dpcd_buf != dpcd_buf) { @@ -207,18 +394,18 @@ static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_st } } - intel_dp_aux_set_backlight(conn_state, - connector->panel.backlight.level); - set_aux_backlight_enable(intel_dp, true); + intel_dp_aux_vesa_set_backlight(conn_state, + connector->panel.backlight.level); + set_vesa_backlight_enable(intel_dp, true); } -static void intel_dp_aux_disable_backlight(const struct drm_connector_state *old_conn_state) +static void intel_dp_aux_vesa_disable_backlight(const struct drm_connector_state *old_conn_state) { - set_aux_backlight_enable(enc_to_intel_dp(to_intel_encoder(old_conn_state->best_encoder)), - false); + set_vesa_backlight_enable(enc_to_intel_dp(to_intel_encoder(old_conn_state->best_encoder)), + false); } -static u32 intel_dp_aux_calc_max_backlight(struct intel_connector *connector) +static u32 intel_dp_aux_vesa_calc_max_backlight(struct intel_connector *connector) { struct drm_i915_private *i915 = to_i915(connector->base.dev); struct intel_dp *intel_dp = intel_attached_dp(connector); @@ -285,31 +472,31 @@ static u32 intel_dp_aux_calc_max_backlight(struct intel_connector *connector) DRM_DEBUG_KMS("Failed to write aux pwmgen bit count\n"); return max_backlight; } - panel->backlight.pwmgen_bit_count = pn; + panel->backlight.edp.vesa.pwmgen_bit_count = pn; max_backlight = (1 << pn) - 1; return max_backlight; } -static int intel_dp_aux_setup_backlight(struct intel_connector *connector, - enum pipe pipe) +static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector, + enum pipe pipe) { struct intel_panel *panel = &connector->panel; - panel->backlight.max = intel_dp_aux_calc_max_backlight(connector); + panel->backlight.max = intel_dp_aux_vesa_calc_max_backlight(connector); if (!panel->backlight.max) return -ENODEV; panel->backlight.min = 0; - panel->backlight.level = intel_dp_aux_get_backlight(connector); + panel->backlight.level = intel_dp_aux_vesa_get_backlight(connector); panel->backlight.enabled = panel->backlight.level != 0; return 0; } static bool -intel_dp_aux_display_control_capable(struct intel_connector *connector) +intel_dp_aux_supports_vesa_backlight(struct intel_connector *connector) { struct intel_dp *intel_dp = intel_attached_dp(connector); @@ -325,41 +512,88 @@ intel_dp_aux_display_control_capable(struct intel_connector *connector) return false; } -int intel_dp_aux_init_backlight_funcs(struct intel_connector *intel_connector) +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, +}; + +int intel_dp_aux_init_backlight_funcs(struct intel_connector *connector) { - struct intel_panel *panel = &intel_connector->panel; - struct intel_dp *intel_dp = enc_to_intel_dp(intel_connector->encoder); - struct drm_device *dev = intel_connector->base.dev; - struct drm_i915_private *dev_priv = to_i915(dev); + struct drm_device *dev = connector->base.dev; + struct intel_panel *panel = &connector->panel; + struct drm_i915_private *i915 = to_i915(dev); + bool try_intel_interface = false, try_vesa_interface = false; - if (i915_modparams.enable_dpcd_backlight == 0 || - !intel_dp_aux_display_control_capable(intel_connector)) + /* Check the VBT and user's module parameters to figure out which + * interfaces to probe + */ + switch (i915_modparams.enable_dpcd_backlight) { + case INTEL_DP_AUX_BACKLIGHT_OFF: return -ENODEV; + case INTEL_DP_AUX_BACKLIGHT_AUTO: + switch (i915->vbt.backlight.type) { + case INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE: + try_vesa_interface = true; + break; + case INTEL_BACKLIGHT_DISPLAY_DDI: + try_intel_interface = true; + try_vesa_interface = true; + break; + default: + return -ENODEV; + } + break; + case INTEL_DP_AUX_BACKLIGHT_ON: + if (i915->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; + } /* - * There are a lot of machines that don't advertise the backlight - * control interface to use properly in their VBIOS, :\ + * A lot of eDP panels in the wild will report supporting both the + * Intel proprietary backlight control interface, and the VESA + * backlight control interface. Many of these panels are liars though, + * and will only work with the Intel interface. So, always probe for + * that first. */ - if (dev_priv->vbt.backlight.type != - INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE && - i915_modparams.enable_dpcd_backlight != 1 && - !drm_dp_has_quirk(&intel_dp->desc, intel_dp->edid_quirks, - DP_QUIRK_FORCE_DPCD_BACKLIGHT)) { - DRM_DEV_INFO(dev->dev, - "Panel advertises DPCD backlight support, but " - "VBT disagrees. If your backlight controls " - "don't work try booting with " - "i915.enable_dpcd_backlight=1. If your machine " - "needs this, please file a _new_ bug report on " - "drm/i915, see " FDO_BUG_URL " for details.\n"); - return -ENODEV; + if (try_intel_interface && + intel_dp_aux_supports_hdr_backlight(connector)) { + DRM_DEV_DEBUG_DRIVER(dev->dev, + "Using Intel proprietary eDP backlight controls\n"); + + panel->backlight.setup = intel_dp_aux_hdr_setup_backlight; + panel->backlight.enable = intel_dp_aux_hdr_enable_backlight; + panel->backlight.disable = intel_dp_aux_hdr_disable_backlight; + panel->backlight.set = intel_dp_aux_hdr_set_backlight; + panel->backlight.get = intel_dp_aux_hdr_get_backlight; + + return 0; } - panel->backlight.setup = intel_dp_aux_setup_backlight; - panel->backlight.enable = intel_dp_aux_enable_backlight; - panel->backlight.disable = intel_dp_aux_disable_backlight; - panel->backlight.set = intel_dp_aux_set_backlight; - panel->backlight.get = intel_dp_aux_get_backlight; + if (try_vesa_interface && + intel_dp_aux_supports_vesa_backlight(connector)) { + DRM_DEV_DEBUG_DRIVER(dev->dev, + "Using VESA eDP backlight controls\n"); + panel->backlight.setup = intel_dp_aux_vesa_setup_backlight; + panel->backlight.enable = intel_dp_aux_vesa_enable_backlight; + panel->backlight.disable = intel_dp_aux_vesa_disable_backlight; + panel->backlight.set = intel_dp_aux_vesa_set_backlight; + panel->backlight.get = intel_dp_aux_vesa_get_backlight; - return 0; + return 0; + } + + return -ENODEV; } diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c index add00ec1f787..a1f939988240 100644 --- a/drivers/gpu/drm/i915/i915_params.c +++ b/drivers/gpu/drm/i915/i915_params.c @@ -165,7 +165,7 @@ i915_param_named_unsafe(inject_probe_failure, uint, 0400, i915_param_named(enable_dpcd_backlight, int, 0600, "Enable support for DPCD backlight control" - "(-1=use per-VBT LFP backlight type setting [default], 0=disabled, 1=enabled)"); + "(-1=use per-VBT LFP backlight type setting [default], 0=disabled, 1=enable, 2=force VESA interface, 3=force Intel interface)"); #if IS_ENABLED(CONFIG_DRM_I915_GVT) i915_param_named(enable_gvt, bool, 0400, -- 2.27.0