platform/chrome: cros_ec_typec: Thunderbolt support

Add support for entering and exiting Thunderbolt alt-mode using AP
driven alt-mode.

Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Link: https://lore.kernel.org/r/20241213153543.v5.7.Ic61ced3cdfb5d6776435356061f12307da719829@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index 23aa594fbb5b2646fa32ab0ff4d7183ee50c9f90..1b2f2bd096622f985ac223dc70dde0a8f3a6cb89 100644 (file)
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -249,6 +249,7 @@ config CROS_EC_TYPEC
        depends on USB_ROLE_SWITCH
        default MFD_CROS_EC_DEV
        select CROS_EC_TYPEC_ALTMODES if TYPEC_DP_ALTMODE
+       select CROS_EC_TYPEC_ALTMODES if TYPEC_TBT_ALTMODE
        help
          If you say Y here, you get support for accessing Type C connector
          information from the Chrome OS EC.

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 1bcaa72693950341f292774bcd279245d70a188f..1ac5798d887fcc841b637cf498befe0322726632 100644 (file)
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -303,18 +303,19 @@ static int cros_typec_register_port_altmodes(struct cros_typec_data *typec,
 
        /*
         * Register TBT compatibility alt mode. The EC will not enter the mode
-        * if it doesn't support it, so it's safe to register it unconditionally
-        * here for now.
+        * if it doesn't support it and it will not enter automatically by
+        * design so we can use the |ap_driven_altmode| feature to check if we
+        * should register it.
         */
-       memset(&desc, 0, sizeof(desc));
-       desc.svid = USB_TYPEC_TBT_SID;
-       desc.mode = TYPEC_ANY_MODE;
-       amode = typec_port_register_altmode(port->port, &desc);
-       if (IS_ERR(amode))
-               return PTR_ERR(amode);
-       port->port_altmode[CROS_EC_ALTMODE_TBT] = amode;
-       typec_altmode_set_drvdata(amode, port);
-       amode->ops = &port_amode_ops;
+       if (typec->ap_driven_altmode) {
+               memset(&desc, 0, sizeof(desc));
+               desc.svid = USB_TYPEC_TBT_SID;
+               desc.mode = TBT_MODE;
+               amode = cros_typec_register_thunderbolt(port, &desc);
+               if (IS_ERR(amode))
+                       return PTR_ERR(amode);
+               port->port_altmode[CROS_EC_ALTMODE_TBT] = amode;
+       }
 
        port->state.alt = NULL;
        port->state.mode = TYPEC_STATE_USB;

diff --git a/drivers/platform/chrome/cros_typec_altmode.c b/drivers/platform/chrome/cros_typec_altmode.c
index 6e736168ccc3f6e21d8c19175af438e30124ffa7..557340b53af03b42b77a84ce0766e10372a85f15 100644 (file)
--- a/drivers/platform/chrome/cros_typec_altmode.c
+++ b/drivers/platform/chrome/cros_typec_altmode.c
@@ -10,6 +10,7 @@
 #include <linux/mutex.h>
 #include <linux/workqueue.h>
 #include <linux/usb/typec_dp.h>
+#include <linux/usb/typec_tbt.h>
 #include <linux/usb/pd_vdo.h>
 
 #include "cros_typec_altmode.h"
@@ -72,6 +73,8 @@ static int cros_typec_altmode_enter(struct typec_altmode *alt, u32 *vdo)
 
        if (adata->sid == USB_TYPEC_DP_SID)
                req.mode_to_enter = CROS_EC_ALTMODE_DP;
+       else if (adata->sid == USB_TYPEC_TBT_SID)
+               req.mode_to_enter = CROS_EC_ALTMODE_TBT;
        else
                return -EOPNOTSUPP;
 
@@ -196,6 +199,56 @@ static int cros_typec_displayport_vdm(struct typec_altmode *alt, u32 header,
        return 0;
 }
 
+static int cros_typec_thunderbolt_vdm(struct typec_altmode *alt, u32 header,
+                                     const u32 *data, int count)
+{
+       struct cros_typec_altmode_data *adata = typec_altmode_get_drvdata(alt);
+
+       int cmd_type = PD_VDO_CMDT(header);
+       int cmd = PD_VDO_CMD(header);
+       int svdm_version;
+
+       svdm_version = typec_altmode_get_svdm_version(alt);
+       if (svdm_version < 0)
+               return svdm_version;
+
+       mutex_lock(&adata->lock);
+
+       switch (cmd_type) {
+       case CMDT_INIT:
+               if (PD_VDO_SVDM_VER(header) < svdm_version) {
+                       typec_partner_set_svdm_version(adata->port->partner,
+                                                      PD_VDO_SVDM_VER(header));
+                       svdm_version = PD_VDO_SVDM_VER(header);
+               }
+
+               adata->header = VDO(adata->sid, 1, svdm_version, cmd);
+               adata->header |= VDO_OPOS(adata->mode);
+
+               switch (cmd) {
+               case CMD_ENTER_MODE:
+                       /* Don't respond to the enter mode vdm because it
+                        * triggers mux configuration. This is handled directly
+                        * by the cros_ec_typec driver so the Thunderbolt driver
+                        * doesn't need to be involved.
+                        */
+                       break;
+               default:
+                       adata->header |= VDO_CMDT(CMDT_RSP_ACK);
+                       schedule_work(&adata->work);
+                       break;
+               }
+
+               break;
+       default:
+               break;
+       }
+
+       mutex_unlock(&adata->lock);
+       return 0;
+}
+
+
 static int cros_typec_altmode_vdm(struct typec_altmode *alt, u32 header,
                                      const u32 *data, int count)
 {
@@ -207,6 +260,9 @@ static int cros_typec_altmode_vdm(struct typec_altmode *alt, u32 header,
        if (adata->sid == USB_TYPEC_DP_SID)
                return cros_typec_displayport_vdm(alt, header, data, count);
 
+       if (adata->sid == USB_TYPEC_TBT_SID)
+               return cros_typec_thunderbolt_vdm(alt, header, data, count);
+
        return -EINVAL;
 }
 
@@ -283,3 +339,35 @@ cros_typec_register_displayport(struct cros_typec_port *port,
        return alt;
 }
 #endif
+
+#if IS_ENABLED(CONFIG_TYPEC_TBT_ALTMODE)
+struct typec_altmode *
+cros_typec_register_thunderbolt(struct cros_typec_port *port,
+                               struct typec_altmode_desc *desc)
+{
+       struct typec_altmode *alt;
+       struct cros_typec_altmode_data *adata;
+
+       alt = typec_port_register_altmode(port->port, desc);
+       if (IS_ERR(alt))
+               return alt;
+
+       adata = devm_kzalloc(&alt->dev, sizeof(*adata), GFP_KERNEL);
+       if (!adata) {
+               typec_unregister_altmode(alt);
+               return ERR_PTR(-ENOMEM);
+       }
+
+       INIT_WORK(&adata->work, cros_typec_altmode_work);
+       adata->alt = alt;
+       adata->port = port;
+       adata->ap_mode_entry = true;
+       adata->sid = desc->svid;
+       adata->mode = desc->mode;
+
+       typec_altmode_set_ops(alt, &cros_typec_altmode_ops);
+       typec_altmode_set_drvdata(alt, adata);
+
+       return alt;
+}
+#endif

diff --git a/drivers/platform/chrome/cros_typec_altmode.h b/drivers/platform/chrome/cros_typec_altmode.h
index ed00ee7a402baac5de0a5860bb97f779265d6590..3f2aa95d065af709643ad653df487a9987780da4 100644 (file)
--- a/drivers/platform/chrome/cros_typec_altmode.h
+++ b/drivers/platform/chrome/cros_typec_altmode.h
@@ -34,4 +34,18 @@ static inline int cros_typec_displayport_status_update(struct typec_altmode *alt
        return 0;
 }
 #endif
+
+#if IS_ENABLED(CONFIG_TYPEC_TBT_ALTMODE)
+struct typec_altmode *
+cros_typec_register_thunderbolt(struct cros_typec_port *port,
+                               struct typec_altmode_desc *desc);
+#else
+static inline struct typec_altmode *
+cros_typec_register_thunderbolt(struct cros_typec_port *port,
+                               struct typec_altmode_desc *desc)
+{
+       return typec_port_register_altmode(port->port, desc);
+}
+#endif
+
 #endif /* __CROS_TYPEC_ALTMODE_H__ */