5.15-stable review patch. If anyone has any objections, please let me know.
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From: Mika Westerberg mika.westerberg@linux.intel.com
commit a9fdf5f933a6f2b358fad0194b1287b67f6704b1 upstream.
Marek reported that when BlackMagic UltraStudio device is connected the kernel repeatedly tries to enable lane bonding without success making the device non-functional. It looks like the device does not have lane 1 connected at all so even though it is enabled we should not try to bond the lanes. For this reason check that lane 1 is in fact CL0 (connected, active) before attempting to bond the lanes.
Reported-by: Marek Šanta teslan223@gmail.com Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217737 Cc: stable@vger.kernel.org Signed-off-by: Mika Westerberg mika.westerberg@linux.intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/thunderbolt/switch.c | 7 +++++++ 1 file changed, 7 insertions(+)
--- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -2552,6 +2552,13 @@ int tb_switch_lane_bonding_enable(struct !tb_port_is_width_supported(down, 2)) return 0;
+ /* + * Both lanes need to be in CL0. Here we assume lane 0 already be in + * CL0 and check just for lane 1. + */ + if (tb_wait_for_port(down->dual_link_port, false) <= 0) + return -ENOTCONN; + ret = tb_port_lane_bonding_enable(up); if (ret) { tb_port_warn(up, "failed to enable lane bonding\n");