From b329b32854eca71853ce1e3e06b573c25b262d5f Mon Sep 17 00:00:00 2001 From: Jani Nikula Date: Fri, 8 Nov 2013 16:48:57 +0200 Subject: [PATCH] drm/i915: fix gen2-gen3 backlight set Citing Jani's response to Imre's question in the review discussion: > According to the gen2/3 bspec I have, the correct mask is > BACKLIGHT_DUTY_CYCLE_MASK_PNV only in case of IS_PINEVIEW(dev), for > everything else it's BACKLIGHT_DUTY_CYCLE_MASK. What you say is correct, but we've treated all gen2/3 similar to PNV since commit ca88479c1c3b7b1a9f94320745f5331e1de77f80 Author: Keith Packard Date: Fri Nov 18 11:09:24 2011 -0800 drm/i915: Treat pre-gen4 backlight duty cycle value consistently i.e. we only use the high 15 bits for all gen2/3. For non-PNV this just means the lowest bit is always zero. For PNV the lowest bit has a different meaning in both the PWM freq and duty cycle fields. Signed-off-by: Jani Nikula Reviewed-by: Imre Deak [danvet: Make the commit message less empty.] Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_panel.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c index a821949a9c7a..e82b2dd93eef 100644 --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -555,7 +555,7 @@ static void i9xx_set_backlight(struct intel_connector *connector, u32 level) { struct drm_device *dev = connector->base.dev; struct drm_i915_private *dev_priv = dev->dev_private; - u32 tmp; + u32 tmp, mask; if (is_backlight_combination_mode(dev)) { u32 max = intel_panel_get_max_backlight(connector); @@ -570,10 +570,14 @@ static void i9xx_set_backlight(struct intel_connector *connector, u32 level) pci_write_config_byte(dev->pdev, PCI_LBPC, lbpc); } - if (INTEL_INFO(dev)->gen < 4) + if (IS_GEN4(dev)) { + mask = BACKLIGHT_DUTY_CYCLE_MASK; + } else { level <<= 1; + mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV; + } - tmp = I915_READ(BLC_PWM_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK; + tmp = I915_READ(BLC_PWM_CTL) & ~mask; I915_WRITE(BLC_PWM_CTL, tmp | level); } -- 2.20.1