From e5bb88e961e5e3e72e3cc3a866a232115bd15e1e Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Thu, 18 Nov 2021 09:10:59 +0200
Subject: [PATCH] thunderbolt: Do not program path HopIDs for USB4 routers
References: jsc#SLE-19357
Patch-mainline: v5.17-rc1
Git-commit: e5bb88e961e5e3e72e3cc3a866a232115bd15e1e
These fields are marked read-only for USB4 routers so do not touch them
in that case. Update the kernel-doc of tb_dp_port_set_hops() to reflect
this too.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
drivers/thunderbolt/switch.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 463cfdc0b42f..e00f4b878b56 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -1322,7 +1322,9 @@ int tb_dp_port_hpd_clear(struct tb_port *port)
* @aux_tx: AUX TX Hop ID
* @aux_rx: AUX RX Hop ID
*
- * Programs specified Hop IDs for DP IN/OUT port.
+ * Programs specified Hop IDs for DP IN/OUT port. Can be called for USB4
+ * router DP adapters too but does not program the values as the fields
+ * are read-only.
*/
int tb_dp_port_set_hops(struct tb_port *port, unsigned int video,
unsigned int aux_tx, unsigned int aux_rx)
@@ -1330,6 +1332,9 @@ int tb_dp_port_set_hops(struct tb_port *port, unsigned int video,
u32 data[2];
int ret;
+ if (tb_switch_is_usb4(port->sw))
+ return 0;
+
ret = tb_port_read(port, data, TB_CFG_PORT,
port->cap_adap + ADP_DP_CS_0, ARRAY_SIZE(data));
if (ret)
--
2.26.2