ons 2018-09-12 klockan 10:49 +0200 skrev gregkh@linuxfoundation.org:

...

The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

Updated patch attached. Build and boot tested.

Mainline commit id is 299c2a904b1e8d5096d4813df6371357d97a6cd1

Regards, Fredrik

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From f371bbae4541047a1ee34f11f25bc15e864df625 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Fredrik=20Sch=C3=B6n?= fredrik.schon@gmail.com Date: Wed, 12 Sep 2018 20:43:42 +0200 Subject: [PATCH] drm/i915: Increase LSPCON timeout MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit

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.

Backported to 4.14-stable

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 --- drivers/gpu/drm/i915/intel_lspcon.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_lspcon.c b/drivers/gpu/drm/i915/intel_lspcon.c index beb9baaf2f2e..f71fef10ecc6 100644 --- 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_mode(struct intel_lspcon *lspcon, 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");