From 5075222b04a28bff6bf1c66a7baced787be6b6de Mon Sep 17 00:00:00 2001 From: Jani Nikula Date: Tue, 1 Dec 2015 10:23:51 +0200 Subject: drm/i915: use default 200 Hz backlight frequency If the backlight modulation frequency can't be extracted from the registers or from VBT, use 200 Hz as the default. This may enable backlight on some machines that previously failed. Reviewed-by: Imre Deak Tested-by: Imre Deak Signed-off-by: Jani Nikula Link: http://patchwork.freedesktop.org/patch/msgid/1448958232-26520-2-git-send-email-jani.nikula@intel.com diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c index 2d16963..2b25497 100644 --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -1393,14 +1393,18 @@ static u32 get_backlight_max_vbt(struct intel_connector *connector) u16 pwm_freq_hz = dev_priv->vbt.backlight.pwm_freq_hz; u32 pwm; - if (!pwm_freq_hz) { - DRM_DEBUG_KMS("backlight frequency not specified in VBT\n"); + if (!panel->backlight.hz_to_pwm) { + DRM_DEBUG_KMS("backlight frequency conversion not supported\n"); return 0; } - if (!panel->backlight.hz_to_pwm) { - DRM_DEBUG_KMS("backlight frequency setting from VBT currently not supported on this platform\n"); - return 0; + if (pwm_freq_hz) { + DRM_DEBUG_KMS("VBT defined backlight frequency %u Hz\n", + pwm_freq_hz); + } else { + pwm_freq_hz = 200; + DRM_DEBUG_KMS("default backlight frequency %u Hz\n", + pwm_freq_hz); } pwm = panel->backlight.hz_to_pwm(connector, pwm_freq_hz); @@ -1409,8 +1413,6 @@ static u32 get_backlight_max_vbt(struct intel_connector *connector) return 0; } - DRM_DEBUG_KMS("backlight frequency %u Hz from VBT\n", pwm_freq_hz); - return pwm; } -- cgit v0.10.2