From bd646c768a934d28e574ee940d6759c7954a024d Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Tue, 5 Nov 2024 09:19:02 +0200 Subject: [PATCH] thunderbolt: Fix connection issue with Pluggable UD-4VPD dock Rick reported that his Pluggable USB4 dock does not work anymore after upgrading to v6.10 kernel. It looks like commit c6ca1ac9f472 ("thunderbolt: Increase sideband access polling delay") makes the device router enumeration happen later than what might be expected by the dock (although there is no such limit in the USB4 spec) which probably makes it assume there is something wrong with the high-speed link and reset it. After the link is reset the same issue happens again and again. For this reason lower the sideband access delay from 5ms to 1ms. This seems to work fine according to Rick's testing. Reported-by: Rick Lahaye Closes: https://lore.kernel.org/linux-usb/000f01db247b$d10e1520$732a3f60$@581238.xyz/ Tested-by: Rick Lahaye Fixes: c6ca1ac9f472 ("thunderbolt: Increase sideband access polling delay") Cc: stable@vger.kernel.org Acked-by: Greg Kroah-Hartman Reviewed-by: Mario Limonciello Signed-off-by: Mika Westerberg --- drivers/thunderbolt/usb4.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c index 0a9b4aeb3fa1..402fdf8b1cde 100644 --- a/drivers/thunderbolt/usb4.c +++ b/drivers/thunderbolt/usb4.c @@ -48,7 +48,7 @@ enum usb4_ba_index { /* Delays in us used with usb4_port_wait_for_bit() */ #define USB4_PORT_DELAY 50 -#define USB4_PORT_SB_DELAY 5000 +#define USB4_PORT_SB_DELAY 1000 static int usb4_native_switch_op(struct tb_switch *sw, u16 opcode, u32 *metadata, u8 *status,