3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Krzysztof Mazur <krzysiek@xxxxxxxxxxxx> commit 0fde901f1ddd2ce0e380a6444f1fb7ca555859e9 upstream. Some broken systems (like HP nc6120) in some cases, usually after LID close/open, enable VGA plane, making display unusable (black screen on LVDS, some strange mode on VGA output). We used to disable VGA plane only once at startup. Now we also check, if VGA plane is still disabled while changing mode, and fix that if something changed it. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=57434 Signed-off-by: Krzysztof Mazur <krzysiek@xxxxxxxxxxxx> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx> [bwh: Backported to 3.2: intel_modeset_setup_hw_state() does not exist, so call i915_redisable_vga() directly from intel_lid_notify()] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> Cc: Qiang Huang <h.huangqiang@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/intel_display.c | 17 +++++++++++++++++ drivers/gpu/drm/i915/intel_lvds.c | 1 + 3 files changed, 19 insertions(+) --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1397,6 +1397,7 @@ static inline void intel_unregister_dsm_ #endif /* CONFIG_ACPI */ /* modesetting */ +extern void i915_redisable_vga(struct drm_device *dev); extern void intel_modeset_init(struct drm_device *dev); extern void intel_modeset_gem_init(struct drm_device *dev); extern void intel_modeset_cleanup(struct drm_device *dev); --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -9254,6 +9254,23 @@ static void i915_disable_vga(struct drm_ POSTING_READ(vga_reg); } +void i915_redisable_vga(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + u32 vga_reg; + + if (HAS_PCH_SPLIT(dev)) + vga_reg = CPU_VGACNTRL; + else + vga_reg = VGACNTRL; + + if (I915_READ(vga_reg) != VGA_DISP_DISABLE) { + DRM_DEBUG_KMS("Something enabled VGA plane, disabling it\n"); + I915_WRITE(vga_reg, VGA_DISP_DISABLE); + POSTING_READ(vga_reg); + } +} + void intel_modeset_init(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; --- a/drivers/gpu/drm/i915/intel_lvds.c +++ b/drivers/gpu/drm/i915/intel_lvds.c @@ -535,6 +535,7 @@ static int intel_lid_notify(struct notif mutex_lock(&dev->mode_config.mutex); drm_helper_resume_force_mode(dev); + i915_redisable_vga(dev); mutex_unlock(&dev->mode_config.mutex); return NOTIFY_OK; -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html