From: John Barberiz <jbarberi@amd.com>
Date: Fri, 9 Feb 2018 17:48:18 -0500
Subject: drm/amd/display: Add passive dongle support for HPD Rearch
Git-commit: 11fffe45b76d2849a684f2d769bc76901ba0d301
Patch-mainline: v4.17-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

Add HPD delay timer support to
1. Single/dual link DVI.
2. DP to HDMI passive dongle
3. DP to DVI passive dongle.

Signed-off-by: John Barberiz <jbarberi@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link.c |    7 +++++--
 drivers/gpu/drm/amd/display/dc/dc_link.h      |    2 +-
 2 files changed, 6 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -2358,11 +2358,14 @@ void core_link_set_avmute(struct pipe_ct
 	core_dc->hwss.set_avmute(pipe_ctx, enable);
 }
 
-void dc_link_disable_hpd_filter(struct dc_link *link)
+void dc_link_enable_hpd_filter(struct dc_link *link, bool enable)
 {
 	struct gpio *hpd;
 
-	if (!link->is_hpd_filter_disabled) {
+	if (enable) {
+		link->is_hpd_filter_disabled = false;
+		program_hpd_filter(link);
+	} else {
 		link->is_hpd_filter_disabled = true;
 		/* Obtain HPD handle */
 		hpd = get_hpd_gpio(link->ctx->dc_bios, link->link_id, link->ctx->gpio_service);
--- a/drivers/gpu/drm/amd/display/dc/dc_link.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_link.h
@@ -197,7 +197,7 @@ bool dc_link_dp_set_test_pattern(
 	const unsigned char *p_custom_pattern,
 	unsigned int cust_pattern_size);
 
-void dc_link_disable_hpd_filter(struct dc_link *link);
+void dc_link_enable_hpd_filter(struct dc_link *link, bool enable);
 
 /*
  * DPCD access interfaces