On Tue, Sep 09, 2025 at 09:21:33AM +0200, Neil Armstrong wrote:
> On 08/09/2025 23:24, Dmitry Baryshkov wrote:
> > On Mon, Sep 08, 2025 at 03:04:21PM +0200, 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.armstr...@linaro.org>
> > > ---
> > > drivers/phy/qualcomm/phy-qcom-qmp-combo.c | 132
> > > ++++++++++++++++++++++++++++--
> > > 1 file changed, 124 insertions(+), 8 deletions(-)
> >
> > Looking at the patch... Would it be possible to make it more generic? I
> > think some of the RockChips also have similar combo USB+DP PHY (and
> > similar issues). I believe, Mediatek might also have the same issue.
>
> Since they don't use the data-lanes property, it's hard to make it generic
> and I would
> avoid migrating their DT to data-lanes just to solve HDMI on the Thinkpas
> T14s...
I'm waiting for Sebastian to respond regarding the RockChip USBPD PHY.
In the bindings he mentioned having separate USB and DP connectors, so
it might be relevant.
>
> Let's solve this first, and code can be aggregated afterwards if the DT
> representation is correct.
Yep.
>
> >
> > > diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
> > > b/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
> > > index
> > > 7b5af30f1d028c592500e723ecd27b54ed554709..f3f91a69dc8b81e049cd06f7ab4f04baf57776cd
> > > 100644
> > > --- a/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
> > > +++ b/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
> > > @@ -13,6 +13,7 @@
> > > #include <linux/module.h>
> > > #include <linux/of.h>
> > > #include <linux/of_address.h>
> > > +#include <linux/of_graph.h>
> > > #include <linux/phy/phy.h>
> > > #include <linux/platform_device.h>
> > > #include <linux/regulator/consumer.h>
> > > @@ -1744,6 +1745,21 @@ static const u8
> > > qmp_dp_v6_pre_emphasis_hbr_rbr[4][4] = {
> > > { 0x22, 0xff, 0xff, 0xff }
> > > };
> > > +static const u32 usb3_data_lane_mapping[][2] = {
> > > + [TYPEC_ORIENTATION_NORMAL] = { 1, 0 },
> > > + [TYPEC_ORIENTATION_REVERSE] = { 2, 3 },
> > > +};
> > > +
> > > +static const u32 dp_2_data_lanes_mapping[][2] = {
> > > + [TYPEC_ORIENTATION_NORMAL] = { 0, 1 },
> > > + [TYPEC_ORIENTATION_REVERSE] = { 3, 2 },
> > > +};
> > > +
> > > +static const u32 dp_4_data_lanes_mapping[][4] = {
> > > + [TYPEC_ORIENTATION_NORMAL] = { 0, 1, 2, 3 },
> > > + [TYPEC_ORIENTATION_REVERSE] = { 3, 2, 1, 0 },
> > > +};
> > > +
> > > struct qmp_combo;
> > > struct qmp_combo_offsets {
> > > @@ -4167,9 +4183,114 @@ static int qmp_combo_probe(struct platform_device
> > > *pdev)
> > > if (ret)
> > > goto err_node_put;
> > > - 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)) {
> > > + ret = qmp_combo_typec_register(qmp);
> > > + if (ret)
> > > + goto err_node_put;
> > > + } else {
> >
> > At least this needs to be extracted to a function (or set of functions).
>
> Yes I was not sure about how to split, and overall I'm not supeer happy about
> the design.
>
> >
> > > + enum typec_orientation usb3_orientation =
> > > TYPEC_ORIENTATION_NONE;
> > > + enum typec_orientation dp_orientation = TYPEC_ORIENTATION_NONE;
> > > + struct device_node *usb3_ep, *dp_ep;
> > > + u32 data_lanes[4];
> > > + int count, i;
> > > +
> > > + usb3_ep = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
> > > + dp_ep = of_graph_get_endpoint_by_regs(dev->of_node, 0, 1);
> > > +
> > > + if (usb3_ep) {
> > > + ret = of_property_count_u32_elems(usb3_ep,
> > > "data-lanes");
> > > + if (ret == -EINVAL)
> > > + /* Property isn't here, ignore property */
> >
> > In all thsese error cases we are leaking a ref count on usb3_ep and
> > dp_ep.
>
> It would be much simpler to solve in a separate function.
I'd suggest having one function which gets USB3 EP and parses it (and
then puts it), another function which gets DP EP and parses it (and
puts). This way you won't have to worry about reference leaks.
>
> >
> > > + goto usb3_mapping_done;
> > > + if (ret < 0)
> > > + goto err_node_put;
> > > +
> > > + count = ret;
> > > + if (count != 2)
> > > + /* Property size is invalid, ignore property */
> > > + goto usb3_mapping_done;
> > > +
> > > + ret = of_property_read_u32_array(usb3_ep, "data-lanes",
> > > data_lanes, count);
> > > + if (ret)
> > > + goto err_node_put;
> > > +
> > > + for (i = TYPEC_ORIENTATION_NORMAL; i <=
> > > TYPEC_ORIENTATION_REVERSE; i++)
> > > + if (!memcmp(data_lanes,
> > > usb3_data_lane_mapping[i], sizeof(u32) * 2))
> > > + break;
> > > +
> > > + if (i >= TYPEC_ORIENTATION_REVERSE)
> > > + /* Property value is invalid, ignore property */
> > > + goto usb3_mapping_done;
> > > +
> > > + usb3_orientation = i;
> > > + }
> > > +
> > > +usb3_mapping_done:
> > > + of_node_put(usb3_ep);
> > > +
> > > + if (dp_ep) {
> > > + ret = of_property_count_u32_elems(dp_ep, "data-lanes");
> > > + if (ret == -EINVAL)
> > > + /* Property isn't here, ignore property */
> > > + goto dp_mapping_done;
> > > + if (ret < 0)
> > > + goto err_node_put;
> > > +
> > > + count = ret;
> > > + if (count != 2 && count != 4)
> > > + /* Property size is invalid, ignore property */
> > > + goto dp_mapping_done;
> > > +
> > > + ret = of_property_read_u32_array(dp_ep, "data-lanes",
> > > data_lanes, count);
> > > +
> > > + if (ret)
> > > + goto err_node_put;
> > > +
> > > + for (i = TYPEC_ORIENTATION_NORMAL; i <=
> > > TYPEC_ORIENTATION_REVERSE; i++) {
> > > + switch (count) {
> > > + case 2:
> > > + ret = memcmp(data_lanes,
> > > dp_2_data_lanes_mapping[i],
> > > + sizeof(u32) * count);
> > > + break;
> > > + case 4:
> > > + ret = memcmp(data_lanes,
> > > dp_4_data_lanes_mapping[i],
> > > + sizeof(u32) * count);
> > > + break;
> > > + }
> > > +
> > > + if (!ret)
> > > + break;
> > > + }
> > > +
> > > + if (i >= TYPEC_ORIENTATION_REVERSE)
> > > + /* Property value is invalid, ignore property */
> > > + goto dp_mapping_done;
> > > +
> > > + dp_orientation = i;
> > > + }
> > > +
> > > +dp_mapping_done:
> > > + of_node_put(dp_ep);
> > > +
> > > + if (dp_orientation == TYPEC_ORIENTATION_NONE &&
> > > + usb3_orientation != TYPEC_ORIENTATION_NONE) {
> > > + qmp->qmpphy_mode = QMPPHY_MODE_USB3_ONLY;
> > > + qmp->orientation = usb3_orientation;
> > > + } else if (usb3_orientation == TYPEC_ORIENTATION_NONE &&
> > > + dp_orientation != TYPEC_ORIENTATION_NONE) {
> > > + qmp->qmpphy_mode = QMPPHY_MODE_DP_ONLY;
> > > + qmp->orientation = dp_orientation;
> > > + } else if (dp_orientation != TYPEC_ORIENTATION_NONE &&
> > > + dp_orientation == usb3_orientation) {
> > > + qmp->qmpphy_mode = QMPPHY_MODE_USB3DP;
> > > + qmp->orientation = dp_orientation;
> > > + } else {
> > > + dev_warn(dev, "unable to determine orientation & mode
> > > from data-lanes");
> > > + }
> > > + }
> > > ret = drm_aux_bridge_register(dev);
> > > if (ret)
> > > @@ -4189,11 +4310,6 @@ static int qmp_combo_probe(struct platform_device
> > > *pdev)
> > > if (ret)
> > > goto err_node_put;
> > > - /*
> > > - * The hw default is USB3_ONLY, but USB3+DP mode lets us more easily
> > > - * check both sub-blocks' init tables for blunders at probe time.
> > > - */
> > > - qmp->qmpphy_mode = QMPPHY_MODE_USB3DP;
> > > qmp->usb_phy = devm_phy_create(dev, usb_np,
> > > &qmp_combo_usb_phy_ops);
> > > if (IS_ERR(qmp->usb_phy)) {
> > >
> > > --
> > > 2.34.1
> > >
> >
>
--
With best wishes
Dmitry
