diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_panel.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_panel.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c index cb058408c70..cb8cfb7e097 100644 --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -492,6 +492,7 @@ void intel_panel_set_backlight(struct intel_connector *connector, u32 level, enum pipe pipe = intel_get_pipe_from_connector(connector); u32 freq; unsigned long flags; + u64 n; if (!panel->backlight.present || pipe == INVALID_PIPE) return; @@ -502,10 +503,9 @@ void intel_panel_set_backlight(struct intel_connector *connector, u32 level, /* scale to hardware max, but be careful to not overflow */ freq = panel->backlight.max; - if (freq < max) - level = level * freq / max; - else - level = freq / max * level; + n = (u64)level * freq; + do_div(n, max); + level = n; panel->backlight.level = level; if (panel->backlight.device) @@ -1065,6 +1065,11 @@ int intel_panel_setup_backlight(struct drm_connector *connector) unsigned long flags; int ret; + if (!dev_priv->vbt.backlight.present) { + DRM_DEBUG_KMS("native backlight control not available per VBT\n"); + return 0; + } + /* set level and max in panel struct */ spin_lock_irqsave(&dev_priv->backlight_lock, flags); ret = dev_priv->display.setup_backlight(intel_connector); |