goto unlock;
}
- requested_bw = usb4_dp_port_requested_bw(in);
- if (requested_bw < 0) {
- tb_port_dbg(in, "no bandwidth request active\n");
+ 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);
* 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)
{
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;
}