Commit ace75e18 authored by Mika Westerberg's avatar Mika Westerberg
Browse files

thunderbolt: Handle bandwidth allocation mode enablement notification 



When the graphics side enables bandwidth allocation mode the DP IN
adapter sends notification to the connection manager about this.
Currently the handler misses this and tries to allocate 0 Mb/s that then
makes the graphics side to think the request failed.

Fix this by properly handling the enablement notification.

Fixes: 6ce35635 ("thunderbolt: Add support for DisplayPort bandwidth allocation mode")
Signed-off-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
parent 6ce35635

drivers/thunderbolt/tb.c

+7 −3
Original line number Diff line number Diff line
@@ -1746,11 +1746,15 @@ static void tb_handle_dp_bandwidth_request(struct work_struct *work) 
		goto unlock;

	}



	requested_bw = usb4_dp_port_requested_bw(in);

	if (requested_bw < 0) {

	ret = usb4_dp_port_requested_bw(in);

	if (ret < 0) {

		if (ret == -ENODATA)

			tb_port_dbg(in, "no bandwidth request active\n");

		else

			tb_port_warn(in, "failed to read requested bandwidth\n");

		goto unlock;

	}

	requested_bw = ret;



	tb_port_dbg(in, "requested bandwidth %d Mb/s\n", requested_bw);

drivers/thunderbolt/usb4.c

+4 −3
Original line number Diff line number Diff line
@@ -2732,7 +2732,8 @@ int usb4_dp_port_allocate_bw(struct tb_port *port, int bw) 
 * Reads the DPCD (graphics driver) requested bandwidth and returns it

 * in Mb/s. Takes the programmed granularity into account. In case of

 * error returns negative errno. Specifically returns %-EOPNOTSUPP if

 * the adapter does not support bandwidth allocation mode.

 * the adapter does not support bandwidth allocation mode, and %ENODATA

 * if there is no active bandwidth request from the graphics driver.

 */

int usb4_dp_port_requested_bw(struct tb_port *port)

{
@@ -2750,10 +2751,10 @@ int usb4_dp_port_requested_bw(struct tb_port *port) 
	ret = tb_port_read(port, &val, TB_CFG_PORT,

			   port->cap_adap + ADP_DP_CS_8, 1);

	if (ret)

		return 0;

		return ret;



	if (!(val & ADP_DP_CS_8_DR))

		return 0;

		return -ENODATA;



	return (val & ADP_DP_CS_8_REQUESTED_BW_MASK) * granularity;

}