This is a note to let you know that I've just added the patch titled thunderbolt: Add DP OUT resource when DP tunnel is discovered to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: thunderbolt-add-dp-out-resource-when-dp-tunnel-is-discovered.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From b60e31bf18a7064032dbcb73dcb5b58f8a00a110 Mon Sep 17 00:00:00 2001 From: Sanjay R Mehta <sanju.mehta@xxxxxxx> Date: Thu, 4 Aug 2022 05:48:38 -0500 Subject: thunderbolt: Add DP OUT resource when DP tunnel is discovered From: Sanjay R Mehta <sanju.mehta@xxxxxxx> commit b60e31bf18a7064032dbcb73dcb5b58f8a00a110 upstream. If the boot firmware implements a connection manager of its own it may create a DisplayPort tunnel and will be handed off to Linux connection manager, but the DP OUT resource is not saved in the dp_resource list. This patch adds tunnelled DP OUT port to the dp_resource list once the DP tunnel is discovered. Signed-off-by: Sanjay R Mehta <sanju.mehta@xxxxxxx> Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@xxxxxxx> Tested-by: Renjith Pananchikkal <Renjith.Pananchikkal@xxxxxxx> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> Cc: "Limonciello, Mario" <Mario.Limonciello@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/thunderbolt/tb.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) --- a/drivers/thunderbolt/tb.c +++ b/drivers/thunderbolt/tb.c @@ -105,6 +105,32 @@ static void tb_remove_dp_resources(struc } } +static void tb_discover_dp_resource(struct tb *tb, struct tb_port *port) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_port *p; + + list_for_each_entry(p, &tcm->dp_resources, list) { + if (p == port) + return; + } + + tb_port_dbg(port, "DP %s resource available discovered\n", + tb_port_is_dpin(port) ? "IN" : "OUT"); + list_add_tail(&port->list, &tcm->dp_resources); +} + +static void tb_discover_dp_resources(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel; + + list_for_each_entry(tunnel, &tcm->tunnel_list, list) { + if (tb_tunnel_is_dp(tunnel)) + tb_discover_dp_resource(tb, tunnel->dst_port); + } +} + static void tb_switch_discover_tunnels(struct tb_switch *sw, struct list_head *list, bool alloc_hopids) @@ -1396,6 +1422,8 @@ static int tb_start(struct tb *tb) tb_scan_switch(tb->root_switch); /* Find out tunnels created by the boot firmware */ tb_discover_tunnels(tb); + /* Add DP resources from the DP tunnels created by the boot firmware */ + tb_discover_dp_resources(tb); /* * If the boot firmware did not create USB 3.x tunnels create them * now for the whole topology. Patches currently in stable-queue which might be from sanju.mehta@xxxxxxx are queue-5.15/thunderbolt-add-dp-out-resource-when-dp-tunnel-is-discovered.patch