From: Mika Westerberg Date: Wed, 7 Oct 2020 14:08:47 +0000 (+0300) Subject: thunderbolt: Do not clear USB4 router protocol adapter IFC and ISE bits X-Git-Tag: v5.15~2220^2~39^2~21 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=81816f5048bac5f4b202ed1443e9788dfc31a18c;p=platform%2Fkernel%2Flinux-starfive.git thunderbolt: Do not clear USB4 router protocol adapter IFC and ISE bits These fields are marked as vendor defined in the USB4 spec and should not be modified by the software, so only clear them when we are dealing with pre-USB4 hardware. Signed-off-by: Mika Westerberg Acked-by: Yehezkel Bernat Reviewed-by: Greg Kroah-Hartman --- diff --git a/drivers/thunderbolt/path.c b/drivers/thunderbolt/path.c index 03e7b71..7c2c45d 100644 --- a/drivers/thunderbolt/path.c +++ b/drivers/thunderbolt/path.c @@ -406,10 +406,17 @@ static int __tb_path_deactivate_hop(struct tb_port *port, int hop_index, if (!hop.pending) { if (clear_fc) { - /* Clear flow control */ - hop.ingress_fc = 0; + /* + * Clear flow control. Protocol adapters + * IFC and ISE bits are vendor defined + * in the USB4 spec so we clear them + * only for pre-USB4 adapters. + */ + if (!tb_switch_is_usb4(port->sw)) { + hop.ingress_fc = 0; + hop.ingress_shared_buffer = 0; + } hop.egress_fc = 0; - hop.ingress_shared_buffer = 0; hop.egress_shared_buffer = 0; return tb_port_write(port, &hop, TB_CFG_HOPS,