[PATCH v4 2/3] phy: qcom: qmp-combo: get the USB3 & DisplayPort lanes mapping from DT

Konrad Dybcio konrad.dybcio at oss.qualcomm.com
Mon Oct 6 03:08:22 PDT 2025


On 9/30/25 9:39 AM, 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.
> 
> Signed-off-by: Neil Armstrong <neil.armstrong at linaro.org>
> ---

[...]

> +struct qmp_combo_lane_mapping {
> +	unsigned int lanes_count;

"num_lanes"?

> +	enum typec_orientation orientation;
> +	u32 lanes[4];
> +};
> +
> +static const struct qmp_combo_lane_mapping usb3_data_lanes[] = {
> +	{ 2, TYPEC_ORIENTATION_NORMAL, { 1, 0 }},
> +	{ 2, TYPEC_ORIENTATION_REVERSE, { 2, 3 }},
> +};
> +
> +static const struct qmp_combo_lane_mapping dp_data_lanes[] = {
> +	{ 1, TYPEC_ORIENTATION_NORMAL, { 0 }},
> +	{ 1, TYPEC_ORIENTATION_REVERSE, { 3 }},

This is not corroborated by your bindings change ^

I'm also frankly not sure whether it's pin 2 or 3 that 1-lane-DP
would be TXd on

> +	{ 2, TYPEC_ORIENTATION_NORMAL, { 3, 2 }},
> +	{ 2, TYPEC_ORIENTATION_REVERSE, { 0, 1 }},
> +	{ 4, TYPEC_ORIENTATION_NORMAL, { 3, 2, 1, 0 }},
> +	{ 4, TYPEC_ORIENTATION_REVERSE, { 0, 1, 2, 3 }},

Would it be too cheesy to check orientation based like:

static bool qmpphy_mapping_orient_flipped(u32 *data_lanes)
{
	return data_lanes[0] == 0;
}

?

> -	ret = qmp_combo_typec_register(qmp);
> -	if (ret)
> -		goto err_node_put;
> +	qmp->qmpphy_mode = QMPPHY_MODE_USB3DP;
> +
> +	if (of_find_property(dev->of_node, "mode-switch", NULL) ||
> +	    of_find_property(dev->of_node, "orientation-switch", NULL)) {

of_property_present()

Konrad



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