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* [PATCH] platform/chrome: cros_ec_typec: Set Pin Assignment E in DP PORT VDO
@ 2025-04-26  2:48 Benson Leung
  2025-04-28 15:48 ` Jameson Thies
                   ` (2 more replies)
  0 siblings, 3 replies; 6+ messages in thread
From: Benson Leung @ 2025-04-26  2:48 UTC (permalink / raw)
  To: abhishekpandit, jthies, akuchynski, tzungbi, chrome-platform,
	linux-kernel
  Cc: sukoo, bleung, Benson Leung

Pin C and D are used on C-to-C cable applications including docks,
and for USB-C adapters that convert from DP over USB-C to other
video standards.

Pin Assignment E is intended to be used with adapter from USB-C to DP
plugs or receptacles.

All Chromebook USB-C DFPs support DisplayPort Alternate Mode as the DP
Source with support for all 3 pin assignments. Pin Assignment E is required
in order to support if the user attaches a Pin E C-to-DP cable.

Without this, the displayport.c alt mode driver will error out of
dp_altmode_probe with an -ENODEV, as it cannot find a compatible matching
pin assignment between the DFP_D and UFP_D.

Signed-off-by: Benson Leung <bleung@chromium.org>
---
 drivers/platform/chrome/cros_ec_typec.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index d2228720991f..7678e3d05fd3 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -22,8 +22,10 @@
 
 #define DRV_NAME "cros-ec-typec"
 
-#define DP_PORT_VDO	(DP_CONF_SET_PIN_ASSIGN(BIT(DP_PIN_ASSIGN_C) | BIT(DP_PIN_ASSIGN_D)) | \
-				DP_CAP_DFP_D | DP_CAP_RECEPTACLE)
+#define DP_PORT_VDO	(DP_CAP_DFP_D | DP_CAP_RECEPTACLE | \
+			 DP_CONF_SET_PIN_ASSIGN(BIT(DP_PIN_ASSIGN_C) | \
+						BIT(DP_PIN_ASSIGN_D) | \
+						BIT(DP_PIN_ASSIGN_E)))
 
 static void cros_typec_role_switch_quirk(struct fwnode_handle *fwnode)
 {
-- 
2.49.0.850.g28803427d3-goog


^ permalink raw reply related	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2025-04-29  2:52 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-04-26  2:48 [PATCH] platform/chrome: cros_ec_typec: Set Pin Assignment E in DP PORT VDO Benson Leung
2025-04-28 15:48 ` Jameson Thies
2025-04-28 16:24 ` Abhishek Pandit-Subedi
2025-04-28 17:49   ` Benson Leung
2025-04-28 17:48 ` [PATCH v2] " Benson Leung
2025-04-29  2:52   ` Tzung-Bi Shih

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