diff options
Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_bios.c')
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_bios.c | 30 |
1 files changed, 28 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c index 5804eb9faf24..b4d99d0bf696 100644 --- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -425,6 +425,7 @@ parse_lfp_backlight(struct drm_i915_private *dev_priv, const struct bdb_lfp_backlight_data *backlight_data; const struct lfp_backlight_data_entry *entry; int panel_type = dev_priv->vbt.panel_type; + u16 level; backlight_data = find_section(bdb, BDB_LVDS_BACKLIGHT); if (!backlight_data) @@ -459,14 +460,39 @@ parse_lfp_backlight(struct drm_i915_private *dev_priv, dev_priv->vbt.backlight.pwm_freq_hz = entry->pwm_freq_hz; dev_priv->vbt.backlight.active_low_pwm = entry->active_low_pwm; - dev_priv->vbt.backlight.min_brightness = entry->min_brightness; + + if (bdb->version >= 234) { + u16 min_level; + bool scale; + + level = backlight_data->brightness_level[panel_type].level; + min_level = backlight_data->brightness_min_level[panel_type].level; + + if (bdb->version >= 236) + scale = backlight_data->brightness_precision_bits[panel_type] == 16; + else + scale = level > 255; + + if (scale) + min_level = min_level / 255; + + if (min_level > 255) { + drm_warn(&dev_priv->drm, "Brightness min level > 255\n"); + level = 255; + } + dev_priv->vbt.backlight.min_brightness = min_level; + } else { + level = backlight_data->level[panel_type]; + dev_priv->vbt.backlight.min_brightness = entry->min_brightness; + } + drm_dbg_kms(&dev_priv->drm, "VBT backlight PWM modulation frequency %u Hz, " "active %s, min brightness %u, level %u, controller %u\n", dev_priv->vbt.backlight.pwm_freq_hz, dev_priv->vbt.backlight.active_low_pwm ? "low" : "high", dev_priv->vbt.backlight.min_brightness, - backlight_data->level[panel_type], + level, dev_priv->vbt.backlight.controller); } |