4.14-stable review patch. If anyone has any objections, please let me know.
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From: Fredrik Schön fredrikschon@gmail.com
commit 299c2a904b1e8d5096d4813df6371357d97a6cd1 upstream.
100 ms is not enough time for the LSPCON adapter on Intel NUC devices to settle. This causes dropped display modes at boot or screen reconfiguration. Empirical testing can reproduce the error up to a timeout of 190 ms. Basic boot and stress testing at 200 ms has not (yet) failed.
Increase timeout to 400 ms to get some margin of error.
Changes from v1: The initial suggestion of 1000 ms was lowered due to concerns about delaying valid timeout cases. Update patch metadata.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107503 Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1570392 Fixes: 357c0ae9198a ("drm/i915/lspcon: Wait for expected LSPCON mode to settle") Cc: Shashank Sharma shashank.sharma@intel.com Cc: Imre Deak imre.deak@intel.com Cc: Jani Nikula jani.nikula@intel.com Cc: stable@vger.kernel.org # v4.11+ Reviewed-by: Rodrigo Vivi rodrigo.vivi@intel.com Reviewed-by: Shashank Sharma shashank.sharma@intel.com Signed-off-by: Fredrik Schön fredrik.schon@gmail.com Signed-off-by: Jani Nikula jani.nikula@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20180817200728.8154-1-fredrik.... (cherry picked from commit 59f1c8ab30d6f9042562949f42cbd3f3cf69de94) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Reviewed-by: Shashank Sharma shashank.sharma@intel.com Signed-off-by: Fredrik Schön fredrik.schon@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/intel_lspcon.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/i915/intel_lspcon.c +++ b/drivers/gpu/drm/i915/intel_lspcon.c @@ -75,7 +75,7 @@ static enum drm_lspcon_mode lspcon_wait_ lspcon_mode_name(mode));
wait_for((current_mode = lspcon_get_current_mode(lspcon)) == mode || - current_mode == DRM_LSPCON_MODE_INVALID, 100); + current_mode == DRM_LSPCON_MODE_INVALID, 400); if (current_mode != mode) DRM_DEBUG_KMS("LSPCON mode hasn't settled\n");