[PATCH 6.6 04/14] thunderbolt: Create multiple DisplayPort tunnels if there are more DP IN/OUT pairs

From: Alexandru Gagniuc
Date: Tue Oct 01 2024 - 13:33:23 EST


From: Gil Fine <gil.fine@xxxxxxxxxxxxxxx>

[ Upstream commit 8648c6465c025c488e2855c209c0dea1a1a15184 ]

Currently we only create one DisplayPort tunnel even if there would be
more DP IN/OUT pairs available. Specifically this happens when a router
is unplugged and we check if a new DisplayPort tunnel can be created. To
cover this create tunnels as long as we find suitable DP IN/OUT pairs.

Signed-off-by: Gil Fine <gil.fine@xxxxxxxxxxxxxxx>
Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Signed-off-by: Qin Wan <qin.wan@xxxxxx>
Signed-off-by: Alexandru Gagniuc <alexandru.gagniuc@xxxxxx>
---
drivers/thunderbolt/tb.c | 26 +++++++++++++++++---------
1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index 6fc300edad68..e37fb1081420 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -1282,18 +1282,13 @@ static struct tb_port *tb_find_dp_out(struct tb *tb, struct tb_port *in)
return NULL;
}

-static void tb_tunnel_dp(struct tb *tb)
+static bool tb_tunnel_one_dp(struct tb *tb)
{
int available_up, available_down, ret, link_nr;
struct tb_cm *tcm = tb_priv(tb);
struct tb_port *port, *in, *out;
struct tb_tunnel *tunnel;

- if (!tb_acpi_may_tunnel_dp()) {
- tb_dbg(tb, "DP tunneling disabled, not creating tunnel\n");
- return;
- }
-
/*
* Find pair of inactive DP IN and DP OUT adapters and then
* establish a DP tunnel between them.
@@ -1321,11 +1316,11 @@ static void tb_tunnel_dp(struct tb *tb)

if (!in) {
tb_dbg(tb, "no suitable DP IN adapter available, not tunneling\n");
- return;
+ return false;
}
if (!out) {
tb_dbg(tb, "no suitable DP OUT adapter available, not tunneling\n");
- return;
+ return false;
}

/*
@@ -1398,7 +1393,7 @@ static void tb_tunnel_dp(struct tb *tb)
* TMU mode to HiFi for CL0s to work.
*/
tb_increase_tmu_accuracy(tunnel);
- return;
+ return true;

err_free:
tb_tunnel_free(tunnel);
@@ -1413,6 +1408,19 @@ static void tb_tunnel_dp(struct tb *tb)
pm_runtime_put_autosuspend(&out->sw->dev);
pm_runtime_mark_last_busy(&in->sw->dev);
pm_runtime_put_autosuspend(&in->sw->dev);
+
+ return false;
+}
+
+static void tb_tunnel_dp(struct tb *tb)
+{
+ if (!tb_acpi_may_tunnel_dp()) {
+ tb_dbg(tb, "DP tunneling disabled, not creating tunnel\n");
+ return;
+ }
+
+ while (tb_tunnel_one_dp(tb))
+ ;
}

static void tb_enter_redrive(struct tb_port *port)
--
2.45.1