[PATCH 05/19] drm/i915/display: Add debugfs support to avoid joiner

[Ankit Nautiyal]

Currently debugfs for joiner can take a value of 0->dont care and
2->join 2 pipes. Add option to force to use only 1 pipe.

If debugfs is set to 1, force to exactly one pipe (ie. no
joiner despite what the automagic logic is saying).

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
---
 drivers/gpu/drm/i915/display/intel_display_debugfs.c | 3 +++
 drivers/gpu/drm/i915/display/intel_dp.c              | 4 +++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
index 7ceaf01a884a..8b0cb750d9ae 100644
--- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
+++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
@@ -1545,6 +1545,9 @@ static ssize_t i915_joiner_write(struct file *file,
 	switch (force_join_pipes) {
 	case 0:
 		break;
+	case 1:
+		connector->force_joined_pipes = force_join_pipes;
+		break;
 	case 2:
 		if (intel_dp_has_joiner(intel_dp))
 			connector->force_joined_pipes = force_join_pipes;
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 333624fcebd7..65044f63d1f5 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1276,6 +1276,8 @@ int intel_dp_compute_joiner_pipes(struct intel_dp *intel_dp,
 				  int hdisplay, int clock)
 {
 	switch (connector->force_joined_pipes) {
+	case 1:
+		fallthrough;
 	case 2:
 		return connector->force_joined_pipes;
 	default:
@@ -1287,7 +1289,7 @@ int intel_dp_compute_joiner_pipes(struct intel_dp *intel_dp,
 			return 2;
 	}
 
-	return 0;
+	return 1;
 }
 
 bool intel_dp_has_dsc(const struct intel_connector *connector)
-- 
2.45.2