soc: qcom: pmic_glink_altmode: Consume TBT3/USB4 mode notifications

Some compute SoCs support additional operation modes, extending the
existing set of USB3/safe/DP-alt-mode.

The firmware performs all the necessary handshakes for
us and there is no room for error on that level (i.e. the sequences
will match what happens on Windows).

The trade-off with that approach is that the received notifications
trim some of the PDO/EUDO data (particularly the cable/plug parts),
offering a set of similar-in-nature-but-not-the-same indicators.

In an attempt to remedy this, I reconstructed some of it, so that the
connected mux/retimer drivers can continue to behave as expected.

Add support for parsing the aforementioned data coming from PMIC_GLINK
and passing it on to the various Type-C components.

Reviewed-by: Jack Pham <jack.pham@oss.qualcomm.com>
Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20251027-topic-pg_altmode_usb4-v1-1-2931a3ecc146@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

diff --git a/drivers/soc/qcom/pmic_glink_altmode.c b/drivers/soc/qcom/pmic_glink_altmode.c
index 7f11acd33323b7485d5ab7b910a016b804355909..d0afdcb96ee11862d6402c68dfcd071cf6aa0b02 100644 (file)
--- a/drivers/soc/qcom/pmic_glink_altmode.c
+++ b/drivers/soc/qcom/pmic_glink_altmode.c
@@ -14,10 +14,12 @@
 #include <linux/soc/qcom/pdr.h>
 #include <drm/bridge/aux-bridge.h>
 
+#include <linux/usb/pd.h>
 #include <linux/usb/typec_altmode.h>
 #include <linux/usb/typec_dp.h>
 #include <linux/usb/typec_mux.h>
 #include <linux/usb/typec_retimer.h>
+#include <linux/usb/typec_tbt.h>
 
 #include <linux/soc/qcom/pmic_glink.h>
 
@@ -37,11 +39,38 @@ struct usbc_write_req {
        __le32 reserved;
 };
 
-#define NOTIFY_PAYLOAD_SIZE 16
+struct usbc_sc8280x_dp_data {
+       u8 pin_assignment : 6;
+       u8 hpd_state : 1;
+       u8 hpd_irq : 1;
+       u8 res[7];
+};
+
+/* Used for both TBT and USB4 notifications */
+struct usbc_sc8280x_tbt_data {
+       u8 usb_speed : 3;
+       u8 cable_type : 3;
+       /* This field is NOP on USB4, all cables support rounded rates by spec */
+       u8 rounded_cable : 1;
+       u8 power_limited : 1;
+       u8 res[11];
+};
+
 struct usbc_notify {
        struct pmic_glink_hdr hdr;
-       char payload[NOTIFY_PAYLOAD_SIZE];
-       u32 reserved;
+       u8 port_idx;
+       u8 orientation;
+       u8 mux_ctrl;
+#define MUX_CTRL_STATE_NO_CONN                 0
+#define MUX_CTRL_STATE_TUNNELING               4
+
+       u8 res;
+       __le16 vid;
+       __le16 svid;
+       union usbc_sc8280x_extended_data {
+               struct usbc_sc8280x_dp_data dp;
+               struct usbc_sc8280x_tbt_data tbt;
+       } extended_data;
 };
 
 struct usbc_sc8180x_notify {
@@ -74,6 +103,7 @@ struct pmic_glink_altmode_port {
        struct typec_retimer *typec_retimer;
        struct typec_retimer_state retimer_state;
        struct typec_altmode dp_alt;
+       struct typec_altmode tbt_alt;
 
        struct work_struct work;
 
@@ -81,10 +111,12 @@ struct pmic_glink_altmode_port {
 
        enum typec_orientation orientation;
        u16 svid;
+       struct usbc_sc8280x_tbt_data tbt_data;
        u8 dp_data;
        u8 mode;
        u8 hpd_state;
        u8 hpd_irq;
+       u8 mux_ctrl;
 };
 
 #define work_to_altmode(w) container_of((w), struct pmic_glink_altmode, enable_work)
@@ -170,6 +202,102 @@ static void pmic_glink_altmode_enable_dp(struct pmic_glink_altmode *altmode,
                dev_err(altmode->dev, "failed to setup retimer to DP: %d\n", ret);
 }
 
+static void pmic_glink_altmode_enable_tbt(struct pmic_glink_altmode *altmode,
+                                         struct pmic_glink_altmode_port *port)
+{
+       struct usbc_sc8280x_tbt_data *tbt = &port->tbt_data;
+       struct typec_thunderbolt_data tbt_data = {};
+       u32 cable_speed;
+       int ret;
+
+       /* Device Discover Mode VDO */
+       tbt_data.device_mode = TBT_MODE;
+       tbt_data.device_mode |= TBT_SET_ADAPTER(TBT_ADAPTER_TBT3);
+
+       /* Cable Discover Mode VDO */
+       tbt_data.cable_mode = TBT_MODE;
+
+       if (tbt->usb_speed == 0) {
+               cable_speed = TBT_CABLE_USB3_PASSIVE;
+       } else if (tbt->usb_speed == 1) {
+               cable_speed = TBT_CABLE_10_AND_20GBPS;
+       } else {
+               dev_err(altmode->dev,
+                       "Got illegal TBT3 cable speed value (%u), falling back to passive\n",
+                       tbt->usb_speed);
+               cable_speed = TBT_CABLE_USB3_PASSIVE;
+       }
+       tbt_data.cable_mode |= TBT_SET_CABLE_SPEED(cable_speed);
+
+       if (tbt->cable_type) {
+               tbt_data.cable_mode |= TBT_CABLE_ACTIVE_PASSIVE;
+               tbt_data.cable_mode |= TBT_SET_CABLE_ROUNDED(tbt->rounded_cable);
+       }
+
+       /* Enter Mode VDO */
+       tbt_data.enter_vdo |= TBT_MODE;
+       tbt_data.enter_vdo |= TBT_ENTER_MODE_CABLE_SPEED(cable_speed);
+
+       if (tbt->cable_type) {
+               tbt_data.enter_vdo |= TBT_CABLE_ACTIVE_PASSIVE;
+               tbt_data.enter_vdo |= TBT_SET_CABLE_ROUNDED(tbt->rounded_cable);
+       }
+
+       port->state.alt = &port->tbt_alt;
+       port->state.data = &tbt_data;
+       port->state.mode = TYPEC_MODAL_STATE(port->mode);
+
+       ret = typec_mux_set(port->typec_mux, &port->state);
+       if (ret)
+               dev_err(altmode->dev, "failed to switch mux to USB: %d\n", ret);
+
+       port->retimer_state.alt = &port->tbt_alt;
+       port->retimer_state.data = &tbt_data;
+       port->retimer_state.mode = TYPEC_MODAL_STATE(port->mode);
+
+       ret = typec_retimer_set(port->typec_retimer, &port->retimer_state);
+       if (ret)
+               dev_err(altmode->dev, "failed to setup retimer to USB: %d\n", ret);
+}
+
+static void pmic_glink_altmode_enable_usb4(struct pmic_glink_altmode *altmode,
+                                          struct pmic_glink_altmode_port *port)
+{
+       struct usbc_sc8280x_tbt_data *tbt = &port->tbt_data;
+       struct enter_usb_data data = {};
+       int ret;
+
+       data.eudo = FIELD_PREP(EUDO_USB_MODE_MASK, EUDO_USB_MODE_USB4);
+
+       if (tbt->usb_speed == 0) {
+               data.eudo |= FIELD_PREP(EUDO_CABLE_SPEED_MASK, EUDO_CABLE_SPEED_USB4_GEN2);
+       } else if (tbt->usb_speed == 1) {
+               data.eudo |= FIELD_PREP(EUDO_CABLE_SPEED_MASK, EUDO_CABLE_SPEED_USB4_GEN3);
+       } else {
+               pr_err("Got illegal USB4 cable speed value (%u), falling back to G2\n",
+                      tbt->usb_speed);
+               data.eudo |= FIELD_PREP(EUDO_CABLE_SPEED_MASK, EUDO_CABLE_SPEED_USB4_GEN2);
+       }
+
+       data.eudo |= FIELD_PREP(EUDO_CABLE_TYPE_MASK, tbt->cable_type);
+
+       port->state.alt = NULL;
+       port->state.data = &data;
+       port->state.mode = TYPEC_MODE_USB4;
+
+       ret = typec_mux_set(port->typec_mux, &port->state);
+       if (ret)
+               dev_err(altmode->dev, "failed to switch mux to USB: %d\n", ret);
+
+       port->retimer_state.alt = NULL;
+       port->retimer_state.data = &data;
+       port->retimer_state.mode = TYPEC_MODE_USB4;
+
+       ret = typec_retimer_set(port->typec_retimer, &port->retimer_state);
+       if (ret)
+               dev_err(altmode->dev, "failed to setup retimer to USB: %d\n", ret);
+}
+
 static void pmic_glink_altmode_enable_usb(struct pmic_glink_altmode *altmode,
                                          struct pmic_glink_altmode_port *port)
 {
@@ -222,15 +350,15 @@ static void pmic_glink_altmode_worker(struct work_struct *work)
 
        typec_switch_set(alt_port->typec_switch, alt_port->orientation);
 
-       if (alt_port->svid == USB_TYPEC_DP_SID) {
-               if (alt_port->mode == 0xff) {
-                       pmic_glink_altmode_safe(altmode, alt_port);
-               } else {
-                       pmic_glink_altmode_enable_dp(altmode, alt_port,
-                                                    alt_port->mode,
-                                                    alt_port->hpd_state,
-                                                    alt_port->hpd_irq);
-               }
+       if (alt_port->mux_ctrl == MUX_CTRL_STATE_NO_CONN) {
+               pmic_glink_altmode_safe(altmode, alt_port);
+       } else if (alt_port->svid == USB_TYPEC_TBT_SID) {
+               pmic_glink_altmode_enable_tbt(altmode, alt_port);
+       } else if (alt_port->svid == USB_TYPEC_DP_SID) {
+               pmic_glink_altmode_enable_dp(altmode, alt_port,
+                                            alt_port->mode,
+                                            alt_port->hpd_state,
+                                            alt_port->hpd_irq);
 
                if (alt_port->hpd_state)
                        conn_status = connector_status_connected;
@@ -238,6 +366,8 @@ static void pmic_glink_altmode_worker(struct work_struct *work)
                        conn_status = connector_status_disconnected;
 
                drm_aux_hpd_bridge_notify(&alt_port->bridge->dev, conn_status);
+       } else if (alt_port->mux_ctrl == MUX_CTRL_STATE_TUNNELING) {
+               pmic_glink_altmode_enable_usb4(altmode, alt_port);
        } else {
                pmic_glink_altmode_enable_usb(altmode, alt_port);
        }
@@ -314,11 +444,10 @@ static void pmic_glink_altmode_sc8280xp_notify(struct pmic_glink_altmode *altmod
                                               u16 svid, const void *data, size_t len)
 {
        struct pmic_glink_altmode_port *alt_port;
+       const struct usbc_sc8280x_tbt_data *tbt;
+       const struct usbc_sc8280x_dp_data *dp;
        const struct usbc_notify *notify;
        u8 orientation;
-       u8 hpd_state;
-       u8 hpd_irq;
-       u8 mode;
        u8 port;
 
        if (len != sizeof(*notify)) {
@@ -329,11 +458,8 @@ static void pmic_glink_altmode_sc8280xp_notify(struct pmic_glink_altmode *altmod
 
        notify = data;
 
-       port = notify->payload[0];
-       orientation = notify->payload[1];
-       mode = FIELD_GET(SC8280XP_DPAM_MASK, notify->payload[8]) - DPAM_HPD_A;
-       hpd_state = FIELD_GET(SC8280XP_HPD_STATE_MASK, notify->payload[8]);
-       hpd_irq = FIELD_GET(SC8280XP_HPD_IRQ_MASK, notify->payload[8]);
+       port = notify->port_idx;
+       orientation = notify->orientation;
 
        if (port >= ARRAY_SIZE(altmode->ports) || !altmode->ports[port].altmode) {
                dev_dbg(altmode->dev, "notification on undefined port %d\n", port);
@@ -343,9 +469,21 @@ static void pmic_glink_altmode_sc8280xp_notify(struct pmic_glink_altmode *altmod
        alt_port = &altmode->ports[port];
        alt_port->orientation = pmic_glink_altmode_orientation(orientation);
        alt_port->svid = svid;
-       alt_port->mode = mode;
-       alt_port->hpd_state = hpd_state;
-       alt_port->hpd_irq = hpd_irq;
+       alt_port->mux_ctrl = notify->mux_ctrl;
+
+       if (svid == USB_TYPEC_DP_SID) {
+               dp = &notify->extended_data.dp;
+
+               alt_port->mode = dp->pin_assignment - DPAM_HPD_A;
+               alt_port->hpd_state = dp->hpd_state;
+               alt_port->hpd_irq = dp->hpd_irq;
+       } else if (alt_port->mux_ctrl == MUX_CTRL_STATE_TUNNELING) {
+               /* Valid for both USB4 and TBT3 */
+               tbt = &notify->extended_data.tbt;
+
+               alt_port->tbt_data = *tbt;
+       }
+
        schedule_work(&alt_port->work);
 }
 
@@ -471,6 +609,10 @@ static int pmic_glink_altmode_probe(struct auxiliary_device *adev,
                alt_port->dp_alt.mode = USB_TYPEC_DP_MODE;
                alt_port->dp_alt.active = 1;
 
+               alt_port->tbt_alt.svid = USB_TYPEC_TBT_SID;
+               alt_port->tbt_alt.mode = TYPEC_TBT_MODE;
+               alt_port->tbt_alt.active = 1;
+
                alt_port->typec_mux = fwnode_typec_mux_get(fwnode);
                if (IS_ERR(alt_port->typec_mux)) {
                        fwnode_handle_put(fwnode);