FAILED: patch "[PATCH] usb: cdns3: gadget: fix state inconsistency on gadget init" failed to apply to 5.10-stable tree

The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x c32f8748d70c8fc77676ad92ed76cede17bf2c48
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026040711-pond-storage-68f8@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From c32f8748d70c8fc77676ad92ed76cede17bf2c48 Mon Sep 17 00:00:00 2001
From: Yongchao Wu <[email protected]>
Date: Wed, 1 Apr 2026 08:10:00 +0800
Subject: [PATCH] usb: cdns3: gadget: fix state inconsistency on gadget init
failure

When cdns3_gadget_start() fails, the DRD hardware is left in gadget mode while software state remains INACTIVE, creating hardware/software state inconsistency.

When switching to host mode via sysfs:
echo host > /sys/class/usb_role/13180000.usb-role-switch/role

The role state is not set to CDNS_ROLE_STATE_ACTIVE due to the error, so cdns_role_stop() skips cleanup because state is still INACTIVE. This violates the DRD controller design specification (Figure22), which requires returning to idle state before switching roles.

This leads to a synchronous external abort in xhci_gen_setup() when setting up the host controller:

[  516.440698] configfs-gadget 13180000.usb: failed to start g1: -19
[  516.442035] cdns-usb3 13180000.usb: Failed to add gadget
[  516.443278] cdns-usb3 13180000.usb: set role 2 has failed
...
[ 1301.375722] xhci-hcd xhci-hcd.1.auto: xHCI Host Controller
[ 1301.377716] Internal error: synchronous external abort: 96000010 [#1] PREEMPT SMP
[ 1301.382485] pc : xhci_gen_setup+0xa4/0x408
[ 1301.393391] backtrace:
    ...
    xhci_gen_setup+0xa4/0x408    <-- CRASH
    xhci_plat_setup+0x44/0x58
    usb_add_hcd+0x284/0x678
    ...
    cdns_role_set+0x9c/0xbc        <-- Role switch

Fix by calling cdns_drd_gadget_off() in the error path to properly clean up the DRD gadget state.

index 96d2a4c38b3f..8382231af357 100644
@@ -3431,6 +3431,7 @@ static int __cdns3_gadget_init(struct cdns *cdns)
 	ret = cdns3_gadget_start(cdns);
 	if (ret) {
 		pm_runtime_put_sync(cdns->dev);
+		cdns_drd_gadget_off(cdns);
 		return ret;
 	}