Re: [PATCH 1/5] thunderbolt: Silently ignore CLx enabling in case CLx is not supported

[Mika Westerberg <mika.westerberg@linux.intel.com>]

Hi Gil,

On Sun, May 01, 2022 at 11:33:17PM +0300, Gil Fine wrote:
> We can't enable CLx if it is not supported either by the host or device,
> or by the USB4/TBT link (e.g. when an optical cable is used).
> We silently ignore CLx enabling in this case.
> 
> Signed-off-by: Gil Fine <gil.fine@intel.com>
> ---
>  drivers/thunderbolt/tb.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
> index 44d04b651a8b..7419cd1aefba 100644
> --- a/drivers/thunderbolt/tb.c
> +++ b/drivers/thunderbolt/tb.c
> @@ -581,6 +581,7 @@ static void tb_scan_port(struct tb_port *port)
>  	struct tb_cm *tcm = tb_priv(port->sw->tb);
>  	struct tb_port *upstream_port;
>  	struct tb_switch *sw;
> +	int ret;
>  
>  	if (tb_is_upstream_port(port))
>  		return;
> @@ -669,7 +670,9 @@ static void tb_scan_port(struct tb_port *port)
>  	tb_switch_lane_bonding_enable(sw);
>  	/* Set the link configured */
>  	tb_switch_configure_link(sw);
> -	if (tb_switch_enable_clx(sw, TB_CL0S))
> +	/* Silently ignore CLx enabling in case CLx is not supported */
> +	ret = tb_switch_enable_clx(sw, TB_CL0S);
> +	if (ret && ret != -EOPNOTSUPP)

I think we can debug log this and also:

>  		tb_sw_warn(sw, "failed to enable CLx on upstream port\n");

can we use something like "failed to enable CL%d on upstream port\n" and
pass the CL state there too? I think it is useful to see what what CL
state failed.