FAILED: patch "[PATCH] i3c: mipi-i3c-hci: Fix Hot-Join NACK" failed to apply to 6.6-stable tree

The patch below does not apply to the 6.6-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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x fa9586bd77ada1e3861c7bef65f6bb9dcf8d9481
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026031729-cod-volatile-2e41@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

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

From fa9586bd77ada1e3861c7bef65f6bb9dcf8d9481 Mon Sep 17 00:00:00 2001
From: Adrian Hunter <[email protected]>
Date: Fri, 6 Mar 2026 09:24:39 +0200
Subject: [PATCH] i3c: mipi-i3c-hci: Fix Hot-Join NACK

The MIPI I3C HCI host controller driver does not implement Hot-Join handling, yet Hot-Join response control defaults to allowing devices to Hot-Join the bus. Configure HC_CONTROL_HOT_JOIN_CTRL to NACK all Hot-Join attempts.

index dbe93df0c70e..4877a321edf9 100644
@@ -152,7 +152,8 @@ static int i3c_hci_bus_init(struct i3c_master_controller *m)
 	if (hci->quirks & HCI_QUIRK_RESP_BUF_THLD)
 		amd_set_resp_buf_thld(hci);
 
-	reg_set(HC_CONTROL, HC_CONTROL_BUS_ENABLE);
+	/* Enable bus with Hot-Join disabled */
+	reg_set(HC_CONTROL, HC_CONTROL_BUS_ENABLE | HC_CONTROL_HOT_JOIN_CTRL);
 	dev_dbg(&hci->master.dev, "HC_CONTROL = %#x", reg_read(HC_CONTROL));
 
 	return 0;

@@ -764,7 +765,8 @@ static int i3c_hci_runtime_resume(struct device *dev)
 
 	hci->io->resume(hci);
 
-	reg_set(HC_CONTROL, HC_CONTROL_BUS_ENABLE);
+	/* Enable bus with Hot-Join disabled */
+	reg_set(HC_CONTROL, HC_CONTROL_BUS_ENABLE | HC_CONTROL_HOT_JOIN_CTRL);
 
 	return 0;
 }