[PATCH v5 2/3] phy: qcom: qmp-combo: get the USB3 & DisplayPort lanes mapping from DT
Konrad Dybcio
konrad.dybcio at oss.qualcomm.com
Wed Oct 8 02:31:36 PDT 2025
On 10/6/25 3:55 PM, Neil Armstrong wrote:
> The QMP USB3/DP Combo PHY hosts an USB3 phy and a DP PHY on top
> of a combo glue to route either lanes to the 4 shared physical lanes.
>
> The routing of the lanes can be:
> - 2 DP + 2 USB3
> - 4 DP
> - 2 USB3
>
> Get the lanes mapping from DT and stop registering the USB-C
> muxes in favor of a static mode and orientation detemined
> by the lanes mapping.
>
> This allows supporting boards with direct connection of USB3 and
> DisplayPort lanes to the QMP Combo PHY lanes, not using the
> USB-C Altmode feature.
>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov at oss.qualcomm.com>
> Signed-off-by: Neil Armstrong <neil.armstrong at linaro.org>
> ---
[...]
> +static int qmp_combo_get_dt_lanes_mapping(struct device *dev, unsigned int endpoint,
> + u32 *data_lanes, unsigned int max,
> + unsigned int *count)
> +{
> + struct device_node *ep;
> + int ret;
> +
> + ep = of_graph_get_endpoint_by_regs(dev->of_node, 0, endpoint);
> + if (!ep)
> + return -EINVAL;
> +
> + ret = of_property_count_u32_elems(ep, "data-lanes");
> + if (ret < 0)
> + goto err_node_put;
> +
> + *count = ret;
> +
> + ret = of_property_read_u32_array(ep, "data-lanes", data_lanes,
> + max_t(unsigned int, *count, max));
if (*count > max)
return -EINVAL;
> +
> +err_node_put:
> + of_node_put(ep);
__free(device_node)
> +
> + return ret;
> +}
> +
> +static int qmp_combo_get_dt_dp_orientation(struct device *dev,
> + enum typec_orientation *orientation)
> +{
> + unsigned int count;
> + u32 data_lanes[4];
> + int ret;
> +
> + /* DP is described on the first endpoint of the first port */
> + ret = qmp_combo_get_dt_lanes_mapping(dev, 0, data_lanes, 4, &count);
> + if (ret < 0)
> + return ret == -EINVAL ? 0 : ret;
> +
> + /* Search for a match and only update orientation if found */
> + qmp_combo_find_lanes_orientation(dp_data_lanes, ARRAY_SIZE(dp_data_lanes),
> + data_lanes, count, orientation);
You can zero-initialize `count` and drop the custom error parsing above
Konrad
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