[PATCH 32/33] drm/amd/display: Using udelay for specific dongle while edid return defer

[Aurabindo Pillai]

From: jinlong zhang <jinlong.zhang at amd.com>

[why]
Some platform has a limitation of 2ms for udelay

[how]
Add 1ms udelay for specific dongle.

Signed-off-by: jinlong zhang <jinlong.zhang at amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai at amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c       | 7 +++++++
 drivers/gpu/drm/amd/display/dc/dce/dce_aux.c            | 4 +++-
 drivers/gpu/drm/amd/display/include/ddc_service_types.h | 2 ++
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c
index dec12de37642..ef0f50db4907 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c
@@ -39,6 +39,7 @@
 
 #define AUX_POWER_UP_WA_DELAY 500
 #define I2C_OVER_AUX_DEFER_WA_DELAY 70
+#define I2C_OVER_AUX_DEFER_WA_DELAY_1MS 1
 
 /* CV smart dongle slave address for retrieving supported HDTV modes*/
 #define CV_SMART_DONGLE_ADDRESS 0x20
@@ -287,6 +288,12 @@ static uint32_t defer_delay_converter_wa(
 			sizeof(link->dpcd_caps.branch_dev_name)))
 		return defer_delay > I2C_OVER_AUX_DEFER_WA_DELAY ?
 			defer_delay : I2C_OVER_AUX_DEFER_WA_DELAY;
+		if (link->dpcd_caps.branch_dev_id == DP_BRANCH_DEVICE_ID_006037 &&
+			!memcmp(link->dpcd_caps.branch_dev_name,
+				DP_DVI_CONVERTER_ID_5,
+				sizeof(link->dpcd_caps.branch_dev_name)))
+		return defer_delay > I2C_OVER_AUX_DEFER_WA_DELAY_1MS ?
+			I2C_OVER_AUX_DEFER_WA_DELAY_1MS : defer_delay;
 
 	return defer_delay;
 }
diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
index 743042d5905a..cda5fd0464bc 100644
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
@@ -652,8 +652,10 @@ bool dce_aux_transfer_with_retries(struct ddc_service *ddc,
 				} else {
 					if ((*payload->reply == AUX_TRANSACTION_REPLY_AUX_DEFER) ||
 						(*payload->reply == AUX_TRANSACTION_REPLY_I2C_OVER_AUX_DEFER)) {
-						if (payload->defer_delay > 0)
+						if (payload->defer_delay > 1)
 							msleep(payload->defer_delay);
+						else if (payload->defer_delay <= 1)
+							udelay(payload->defer_delay * 1000);
 					}
 				}
 				break;
diff --git a/drivers/gpu/drm/amd/display/include/ddc_service_types.h b/drivers/gpu/drm/amd/display/include/ddc_service_types.h
index 9ad49da50a17..c9be899cd25c 100644
--- a/drivers/gpu/drm/amd/display/include/ddc_service_types.h
+++ b/drivers/gpu/drm/amd/display/include/ddc_service_types.h
@@ -33,6 +33,7 @@
 #define DP_BRANCH_DEVICE_ID_0080E1 0x0080e1
 #define DP_BRANCH_DEVICE_ID_90CC24 0x90CC24
 #define DP_BRANCH_DEVICE_ID_00E04C 0x00E04C
+#define DP_BRANCH_DEVICE_ID_006037 0x006037
 
 enum ddc_result {
 	DDC_RESULT_UNKNOWN = 0,
@@ -122,5 +123,6 @@ static const uint8_t DP_VGA_LVDS_CONVERTER_ID_2[] = "sivarT";
 static const uint8_t DP_VGA_LVDS_CONVERTER_ID_3[] = "dnomlA";
 /*DP to Dual link DVI converter*/
 static const uint8_t DP_DVI_CONVERTER_ID_4[] = "m2DVIa";
+static const uint8_t DP_DVI_CONVERTER_ID_5[] = "3393N2";
 
 #endif /* __DAL_DDC_SERVICE_TYPES_H__ */
-- 
2.25.1