3.16.60-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Florent Flament <contact@xxxxxxxxxxxxxxxxxx> commit e8f48f96db7e482995743f461b3e8a5c1a102533 upstream. Fix `[drm:intel_enable_lvds] *ERROR* timed out waiting for panel to power on` in kernel log at boot time. Toshiba Satellite Z930 laptops needs between 1 and 2 seconds to power on its screen during Intel i915 DRM initialization. This currently results in a `[drm:intel_enable_lvds] *ERROR* timed out waiting for panel to power on` message appearing in the kernel log during boot time and when stopping the machine. This change increases the timeout of the `intel_enable_lvds` function from 1 to 5 seconds, letting enough time for the Satellite 930 LCD screen to power on, and suppressing the error message from the kernel log. This patch has been successfully tested on Linux 4.14 running on a Toshiba Satellite Z930. [vsyrjala: bump the timeout from 2 to 5 seconds to match the DP code and properly cover the max hw timeout of ~4 seconds, and drop the comment about the specific machine since this is not a particulary surprising issue, nor specific to that one machine] Signed-off-by: Florent Flament <contact@xxxxxxxxxxxxxxxxxx> Cc: Pavel Petrovic <ppetrovic@xxxxxxx> Cc: Sérgio M. Basto <sergio@xxxxxxxxxx> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103414 References: https://bugzilla.kernel.org/show_bug.cgi?id=57591 Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20180419160700.19828-1-ville.syrjala@xxxxxxxxxxxxxxx Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx> (cherry picked from commit 280b54ade5914d3b4abe4f0ebe083ddbd4603246) Signed-off-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/intel_lvds.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/i915/intel_lvds.c +++ b/drivers/gpu/drm/i915/intel_lvds.c @@ -219,7 +219,8 @@ static void intel_enable_lvds(struct int I915_WRITE(ctl_reg, I915_READ(ctl_reg) | POWER_TARGET_ON); POSTING_READ(lvds_encoder->reg); - if (wait_for((I915_READ(stat_reg) & PP_ON) != 0, 1000)) + + if (wait_for((I915_READ(stat_reg) & PP_ON) != 0, 5000)) DRM_ERROR("timed out waiting for panel to power on\n"); intel_panel_enable_backlight(intel_connector);
