From 078a033f45471c44befd72ccacf3f31d75299dba Mon Sep 17 00:00:00 2001 From: Li Peng Date: Tue, 15 Sep 2009 13:03:36 +0800 Subject: [PATCH] drm/i915: fix opregion backlight chip detect and range BLC_PWM_CTL2 is for 965+ only, so add device model check for legacy backlight control. For native backlight control, it maps the backlight value (0~255) in opregion ASLE[BCLP] to backlight duty cycle (0~max_backlight) and set into control register. It also add support for IGD device, which follows opregion spec. Signed-off-by: Li Peng Signed-off-by: Jesse Barnes --- drivers/gpu/drm/i915/i915_opregion.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_opregion.c b/drivers/gpu/drm/i915/i915_opregion.c index e4b4e8898e39..2d5193556d3f 100644 --- a/drivers/gpu/drm/i915/i915_opregion.c +++ b/drivers/gpu/drm/i915/i915_opregion.c @@ -148,6 +148,7 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp) struct drm_i915_private *dev_priv = dev->dev_private; struct opregion_asle *asle = dev_priv->opregion.asle; u32 blc_pwm_ctl, blc_pwm_ctl2; + u32 max_backlight, level, shift; if (!(bclp & ASLE_BCLP_VALID)) return ASLE_BACKLIGHT_FAIL; @@ -157,14 +158,25 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp) return ASLE_BACKLIGHT_FAIL; blc_pwm_ctl = I915_READ(BLC_PWM_CTL); - blc_pwm_ctl &= ~BACKLIGHT_DUTY_CYCLE_MASK; blc_pwm_ctl2 = I915_READ(BLC_PWM_CTL2); - if (blc_pwm_ctl2 & BLM_COMBINATION_MODE) + if (IS_I965G(dev) && (blc_pwm_ctl2 & BLM_COMBINATION_MODE)) pci_write_config_dword(dev->pdev, PCI_LBPC, bclp); - else - I915_WRITE(BLC_PWM_CTL, blc_pwm_ctl | ((bclp * 0x101)-1)); - + else { + if (IS_IGD(dev)) { + blc_pwm_ctl &= ~(BACKLIGHT_DUTY_CYCLE_MASK - 1); + max_backlight = (blc_pwm_ctl & BACKLIGHT_MODULATION_FREQ_MASK) >> + BACKLIGHT_MODULATION_FREQ_SHIFT; + shift = BACKLIGHT_DUTY_CYCLE_SHIFT + 1; + } else { + blc_pwm_ctl &= ~BACKLIGHT_DUTY_CYCLE_MASK; + max_backlight = ((blc_pwm_ctl & BACKLIGHT_MODULATION_FREQ_MASK) >> + BACKLIGHT_MODULATION_FREQ_SHIFT) * 2; + shift = BACKLIGHT_DUTY_CYCLE_SHIFT; + } + level = (bclp * max_backlight) / 255; + I915_WRITE(BLC_PWM_CTL, blc_pwm_ctl | (level << shift)); + } asle->cblv = (bclp*0x64)/0xff | ASLE_CBLV_VALID; return 0; -- 2.20.1