[SRU][Q/R][PATCH 2/3] usb: typec: ucsi: Add duplicate detection to nvidia registration path

[AceLan Kao]

From: "Chia-Lin Kao (AceLan)" <acelan.kao at canonical.com>

BugLink: https://bugs.launchpad.net/bugs/2127960

Extend the duplicate altmode detection to ucsi_register_altmodes_nvidia()
which is used when a driver provides the update_altmodes() callback.

This ensures all drivers benefit from duplicate detection, whether they
use the standard registration path or the nvidia path with update_altmodes
callback.

Without this fix, drivers using the nvidia path (like yoga_c630) would
still encounter duplicate altmode registration errors from buggy firmware.

Fixes: a79f16efcd00 ("usb: typec: ucsi: Add support for the partner USB Modes")
Cc: stable at vger.kernel.org
Signed-off-by: Chia-Lin Kao (AceLan) <acelan.kao at canonical.com>
---
 drivers/usb/typec/ucsi/ucsi.c | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index 91a57359835a6..ce103700f685d 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -642,19 +642,25 @@ ucsi_register_altmodes_nvidia(struct ucsi_connector *con, u8 recipient)
 
 	/* now register altmodes */
 	for (i = 0; i < max_altmodes; i++) {
-		memset(&desc, 0, sizeof(desc));
-		if (multi_dp) {
-			desc.svid = updated[i].svid;
-			desc.vdo = updated[i].mid;
-		} else {
-			desc.svid = orig[i].svid;
-			desc.vdo = orig[i].mid;
-		}
-		desc.roles = TYPEC_PORT_DRD;
+		struct ucsi_altmode *altmode_array = multi_dp ? updated : orig;
 
-		if (!desc.svid)
+		if (!altmode_array[i].svid)
 			return 0;
 
+		/*
+		 * Check for duplicates in current array and already
+		 * registered altmodes. Skip if duplicate found.
+		 */
+		if (ucsi_altmode_is_duplicate(con, recipient, altmode_array, i,
+					      altmode_array[i].svid,
+					      altmode_array[i].mid, i))
+			continue;
+
+		memset(&desc, 0, sizeof(desc));
+		desc.svid = altmode_array[i].svid;
+		desc.vdo = altmode_array[i].mid;
+		desc.roles = TYPEC_PORT_DRD;
+
 		ret = ucsi_register_altmode(con, &desc, recipient);
 		if (ret)
 			return ret;
-- 
2.43.0