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authorJani Nikula <jani.nikula@intel.com>2014-04-09 11:22:06 +0300
committerJani Nikula <jani.nikula@intel.com>2014-04-11 13:22:27 +0300
commit39fbc9c8f6765959b55e0b127dd5c57df5a47d67 (patch)
tree6369df006d91ad85b659f26a98f05b725584cca5 /drivers/gpu/drm/i915/intel_bios.c
parent2ab1bc9df01dbc19b55b2271100db7407fa6bfdc (diff)
drm/i915: check VBT for supported backlight type
The only supported types are none and PWM. Other values are obsolete or reserved, don't add them. Tested-by: Kamal Mostafa <kamal@canonical.com> Tested-by: Martin <bugs@mrvanes.com> Tested-by: jrg.otte@gmail.com Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Diffstat (limited to 'drivers/gpu/drm/i915/intel_bios.c')
-rw-r--r--drivers/gpu/drm/i915/intel_bios.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 4867f4cc0938..fa486c5fbb02 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -287,6 +287,9 @@ 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;
@@ -299,6 +302,13 @@ 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, "