[PATCH] drm/i915/mso: using joiner is not possible with eDP MSO

[Jani Nikula]

It's not possible to use the joiner at the same time with eDP MSO. When
a panel needs MSO, it's not optional, so MSO trumps joiner.

v3: Only change intel_dp_has_joiner(), leave debugfs alone (Ville)

Cc: stable at vger.kernel.org
Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1668
Signed-off-by: Jani Nikula <jani.nikula at intel.com>

---

Just the minimal fix for starters to move things along.
---
 drivers/gpu/drm/i915/display/intel_dp.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 9a9bb0f5b7fe..ab33c9de393a 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -465,6 +465,10 @@ bool intel_dp_has_joiner(struct intel_dp *intel_dp)
 	struct intel_encoder *encoder = &intel_dig_port->base;
 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
 
+	/* eDP MSO is not compatible with joiner */
+	if (intel_dp->mso_link_count)
+		return false;
+
 	return DISPLAY_VER(dev_priv) >= 12 ||
 		(DISPLAY_VER(dev_priv) == 11 &&
 		 encoder->port != PORT_A);
-- 
2.39.2