diff mbox series

[1/2] thunderbolt: Explicitly reset plug events delay back to USB4 spec value

Message ID 20220921145434.21659-2-mario.limonciello@amd.com
State New
Headers show
Series Fix some hotplug event issues | expand

Commit Message

Mario Limonciello Sept. 21, 2022, 2:54 p.m. UTC 
If any software has interacted with the USB4 registers before the Linux
USB4 CM runs, it may have modified the plug events delay. It has been
observed that if this value too large, it's possible that hotplugged
devices will negotiate a fallback mode instead in Linux.

To prevent this, explicitly align the plug events delay with the USB4
spec value of 10ms.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 drivers/thunderbolt/switch.c | 1 +
 1 file changed, 1 insertion(+)
diff mbox series

Patch

diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index c63c1f4ff9dc..77d7f07ca075 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -2413,6 +2413,7 @@  int tb_switch_configure(struct tb_switch *sw)
 		 * additional capabilities.
 		 */
 		sw->config.cmuv = USB4_VERSION_1_0;
+		sw->config.plug_events_delay = 0xa;
 
 		/* Enumerate the switch */
 		ret = tb_sw_write(sw, (u32 *)&sw->config + 1, TB_CFG_SWITCH,