Merge tag 'drm-intel-next-2014-04-16' of git://anongit.freedesktop.org/drm-intel...

[cascardo/linux.git] / drivers / gpu / drm / i915 / intel_bios.c

diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 054dbe7..fba9efd 100644 (file)
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -309,6 +309,9 @@ parse_lfp_backlight(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
        const struct bdb_lfp_backlight_data *backlight_data;
        const struct bdb_lfp_backlight_data_entry *entry;
 
+       /* Err to enabling backlight if no backlight block. */
+       dev_priv->vbt.backlight.present = true;
+
        backlight_data = find_section(bdb, BDB_LVDS_BACKLIGHT);
        if (!backlight_data)
                return;
@@ -321,6 +324,13 @@ parse_lfp_backlight(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
 
        entry = &backlight_data->data[panel_type];
 
+       dev_priv->vbt.backlight.present = entry->type == BDB_BACKLIGHT_TYPE_PWM;
+       if (!dev_priv->vbt.backlight.present) {
+               DRM_DEBUG_KMS("PWM backlight not present in VBT (type %u)\n",
+                             entry->type);
+               return;
+       }
+
        dev_priv->vbt.backlight.pwm_freq_hz = entry->pwm_freq_hz;
        dev_priv->vbt.backlight.active_low_pwm = entry->active_low_pwm;
        DRM_DEBUG_KMS("VBT backlight PWM modulation frequency %u Hz, "