drm/i915: don't hard code vlv backlight frequency if unset

Fall back to VBT based backlight modulation frequency if it's not
set. Do not hard code.

This could be a problem if there is no VBT.

Cc: Clint Taylor <clinton.a.taylor@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Clint Taylor <Clinton.A.Taylor@intel.com>
Reviewed-by: Clint Taylor <Clinton.A.Taylor@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index d3a312c409eb4e9b052031b901bd93edc1abaeb4..2034438a06646bf6987b48cfca52bd5a87892cb0 100644 (file)
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -1532,21 +1532,8 @@ static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe
        struct drm_device *dev = connector->base.dev;
        struct drm_i915_private *dev_priv = dev->dev_private;
        struct intel_panel *panel = &connector->panel;
-       enum pipe p;
        u32 ctl, ctl2, val;
 
-       for_each_pipe(dev_priv, p) {
-               u32 cur_val = I915_READ(VLV_BLC_PWM_CTL(p));
-
-               /* Skip if the modulation freq is already set */
-               if (cur_val & ~BACKLIGHT_DUTY_CYCLE_MASK)
-                       continue;
-
-               cur_val &= BACKLIGHT_DUTY_CYCLE_MASK;
-               I915_WRITE(VLV_BLC_PWM_CTL(p), (0xf42 << 16) |
-                          cur_val);
-       }
-
        if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
                return -ENODEV;