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 | 193 |
1 files changed, 136 insertions, 57 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 index 7c653f8c307f..3e706bb850a8 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -57,10 +57,27 @@ static void set_aux_backlight_enable(struct intel_dp *intel_dp, bool enable) */ static u32 intel_dp_aux_get_backlight(struct intel_connector *connector) { - struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + struct intel_dp *intel_dp = intel_attached_dp(connector); u8 read_val[2] = { 0x0 }; + u8 mode_reg; u16 level = 0; + if (drm_dp_dpcd_readb(&intel_dp->aux, + DP_EDP_BACKLIGHT_MODE_SET_REGISTER, + &mode_reg) != 1) { + DRM_DEBUG_KMS("Failed to read the DPCD register 0x%x\n", + DP_EDP_BACKLIGHT_MODE_SET_REGISTER); + return 0; + } + + /* + * If we're not in DPCD control mode yet, the programmed brightness + * value is meaningless and we should assume max brightness + */ + if ((mode_reg & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK) != + DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) + return connector->panel.backlight.max; + if (drm_dp_dpcd_read(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, &read_val, sizeof(read_val)) < 0) { DRM_DEBUG_KMS("Failed to read DPCD register 0x%x\n", @@ -82,7 +99,7 @@ static void intel_dp_aux_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 = enc_to_intel_dp(connector->encoder); + struct intel_dp *intel_dp = intel_attached_dp(connector); u8 vals[2] = { 0x0 }; vals[0] = level; @@ -110,62 +127,29 @@ intel_dp_aux_set_backlight(const struct drm_connector_state *conn_state, u32 lev static bool intel_dp_aux_set_pwm_freq(struct intel_connector *connector) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); - struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); - int freq, fxp, fxp_min, fxp_max, fxp_actual, f = 1; - u8 pn, pn_min, pn_max; + struct intel_dp *intel_dp = intel_attached_dp(connector); + const u8 pn = connector->panel.backlight.pwmgen_bit_count; + int freq, fxp, f, fxp_actual, fxp_min, fxp_max; - /* Find desired value of (F x P) - * Note that, if F x P is out of supported range, the maximum value or - * minimum value will applied automatically. So no need to check that. - */ freq = dev_priv->vbt.backlight.pwm_freq_hz; - DRM_DEBUG_KMS("VBT defined backlight frequency %u Hz\n", freq); if (!freq) { DRM_DEBUG_KMS("Use panel default backlight frequency\n"); return false; } fxp = DIV_ROUND_CLOSEST(KHz(DP_EDP_BACKLIGHT_FREQ_BASE_KHZ), freq); + f = clamp(DIV_ROUND_CLOSEST(fxp, 1 << pn), 1, 255); + fxp_actual = f << pn; - /* Use highest possible value of Pn for more granularity of brightness - * adjustment while satifying the conditions below. - * - Pn is in the range of Pn_min and Pn_max - * - F is in the range of 1 and 255 - * - FxP is within 25% of desired value. - * Note: 25% is arbitrary value and may need some tweak. - */ - if (drm_dp_dpcd_readb(&intel_dp->aux, - DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN, &pn_min) != 1) { - DRM_DEBUG_KMS("Failed to read pwmgen bit count cap min\n"); - return false; - } - if (drm_dp_dpcd_readb(&intel_dp->aux, - DP_EDP_PWMGEN_BIT_COUNT_CAP_MAX, &pn_max) != 1) { - DRM_DEBUG_KMS("Failed to read pwmgen bit count cap max\n"); - return false; - } - pn_min &= DP_EDP_PWMGEN_BIT_COUNT_MASK; - pn_max &= DP_EDP_PWMGEN_BIT_COUNT_MASK; - + /* Ensure frequency is within 25% of desired value */ fxp_min = DIV_ROUND_CLOSEST(fxp * 3, 4); fxp_max = DIV_ROUND_CLOSEST(fxp * 5, 4); - if (fxp_min < (1 << pn_min) || (255 << pn_max) < fxp_max) { - DRM_DEBUG_KMS("VBT defined backlight frequency out of range\n"); - return false; - } - - for (pn = pn_max; pn >= pn_min; pn--) { - f = clamp(DIV_ROUND_CLOSEST(fxp, 1 << pn), 1, 255); - fxp_actual = f << pn; - if (fxp_min <= fxp_actual && fxp_actual <= fxp_max) - break; - } - if (drm_dp_dpcd_writeb(&intel_dp->aux, - DP_EDP_PWMGEN_BIT_COUNT, pn) < 0) { - DRM_DEBUG_KMS("Failed to write aux pwmgen bit count\n"); + if (fxp_min > fxp_actual || fxp_actual > fxp_max) { + DRM_DEBUG_KMS("Actual frequency out of range\n"); return false; } + if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_BACKLIGHT_FREQ_SET, (u8) f) < 0) { DRM_DEBUG_KMS("Failed to write aux backlight freq\n"); @@ -178,7 +162,8 @@ static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_st const struct drm_connector_state *conn_state) { struct intel_connector *connector = to_intel_connector(conn_state->connector); - struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + struct intel_dp *intel_dp = intel_attached_dp(connector); + struct intel_panel *panel = &connector->panel; u8 dpcd_buf, new_dpcd_buf, edp_backlight_mode; if (drm_dp_dpcd_readb(&intel_dp->aux, @@ -197,6 +182,12 @@ static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_st case DP_EDP_BACKLIGHT_CONTROL_MODE_PRODUCT: new_dpcd_buf &= ~DP_EDP_BACKLIGHT_CONTROL_MODE_MASK; new_dpcd_buf |= DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD; + + if (drm_dp_dpcd_writeb(&intel_dp->aux, + DP_EDP_PWMGEN_BIT_COUNT, + panel->backlight.pwmgen_bit_count) < 0) + DRM_DEBUG_KMS("Failed to write aux pwmgen bit count\n"); + break; /* Do nothing when it is already DPCD mode */ @@ -216,8 +207,9 @@ 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_set_backlight(conn_state, connector->panel.backlight.level); } static void intel_dp_aux_disable_backlight(const struct drm_connector_state *old_conn_state) @@ -226,20 +218,91 @@ static void intel_dp_aux_disable_backlight(const struct drm_connector_state *old false); } +static u32 intel_dp_aux_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); + struct intel_panel *panel = &connector->panel; + u32 max_backlight = 0; + int freq, fxp, fxp_min, fxp_max, fxp_actual, f = 1; + u8 pn, pn_min, pn_max; + + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, &pn) == 1) { + pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + max_backlight = (1 << pn) - 1; + } + + /* Find desired value of (F x P) + * Note that, if F x P is out of supported range, the maximum value or + * minimum value will applied automatically. So no need to check that. + */ + freq = i915->vbt.backlight.pwm_freq_hz; + DRM_DEBUG_KMS("VBT defined backlight frequency %u Hz\n", freq); + if (!freq) { + DRM_DEBUG_KMS("Use panel default backlight frequency\n"); + return max_backlight; + } + + fxp = DIV_ROUND_CLOSEST(KHz(DP_EDP_BACKLIGHT_FREQ_BASE_KHZ), freq); + + /* Use highest possible value of Pn for more granularity of brightness + * adjustment while satifying the conditions below. + * - Pn is in the range of Pn_min and Pn_max + * - F is in the range of 1 and 255 + * - FxP is within 25% of desired value. + * Note: 25% is arbitrary value and may need some tweak. + */ + if (drm_dp_dpcd_readb(&intel_dp->aux, + DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN, &pn_min) != 1) { + DRM_DEBUG_KMS("Failed to read pwmgen bit count cap min\n"); + return max_backlight; + } + if (drm_dp_dpcd_readb(&intel_dp->aux, + DP_EDP_PWMGEN_BIT_COUNT_CAP_MAX, &pn_max) != 1) { + DRM_DEBUG_KMS("Failed to read pwmgen bit count cap max\n"); + return max_backlight; + } + pn_min &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + pn_max &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + + fxp_min = DIV_ROUND_CLOSEST(fxp * 3, 4); + fxp_max = DIV_ROUND_CLOSEST(fxp * 5, 4); + if (fxp_min < (1 << pn_min) || (255 << pn_max) < fxp_max) { + DRM_DEBUG_KMS("VBT defined backlight frequency out of range\n"); + return max_backlight; + } + + for (pn = pn_max; pn >= pn_min; pn--) { + f = clamp(DIV_ROUND_CLOSEST(fxp, 1 << pn), 1, 255); + fxp_actual = f << pn; + if (fxp_min <= fxp_actual && fxp_actual <= fxp_max) + break; + } + + DRM_DEBUG_KMS("Using eDP pwmgen bit count of %d\n", pn); + if (drm_dp_dpcd_writeb(&intel_dp->aux, + DP_EDP_PWMGEN_BIT_COUNT, pn) < 0) { + DRM_DEBUG_KMS("Failed to write aux pwmgen bit count\n"); + return max_backlight; + } + panel->backlight.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) { - struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); struct intel_panel *panel = &connector->panel; - if (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT) - panel->backlight.max = 0xFFFF; - else - panel->backlight.max = 0xFF; + panel->backlight.max = intel_dp_aux_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.enabled = panel->backlight.level != 0; return 0; @@ -248,7 +311,7 @@ static int intel_dp_aux_setup_backlight(struct intel_connector *connector, static bool intel_dp_aux_display_control_capable(struct intel_connector *connector) { - struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + struct intel_dp *intel_dp = intel_attached_dp(connector); /* Check the eDP Display control capabilities registers to determine if * the panel can support backlight control over the aux channel @@ -265,15 +328,31 @@ intel_dp_aux_display_control_capable(struct intel_connector *connector) int intel_dp_aux_init_backlight_funcs(struct intel_connector *intel_connector) { struct intel_panel *panel = &intel_connector->panel; - struct drm_i915_private *dev_priv = to_i915(intel_connector->base.dev); + 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); if (i915_modparams.enable_dpcd_backlight == 0 || - (i915_modparams.enable_dpcd_backlight == -1 && - dev_priv->vbt.backlight.type != INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE)) + !intel_dp_aux_display_control_capable(intel_connector)) return -ENODEV; - if (!intel_dp_aux_display_control_capable(intel_connector)) + /* + * There are a lot of machines that don't advertise the backlight + * control interface to use properly in their VBIOS, :\ + */ + if (dev_priv->vbt.backlight.type != + INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE && + !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; + } panel->backlight.setup = intel_dp_aux_setup_backlight; panel->backlight.enable = intel_dp_aux_enable_backlight; |