platform/chrome: cros_ec_typec: Add USB mux control

Add support to configure various Type C switches appropriately using the
Type C connector class API, when the Chrome OS EC informs the AP that
the USB operating mode has been entered.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index d69a88464cef0cef587fd9df0a6c3646371f672c..9ebf9abed16ff5849bb230609ab215fcf9e67776 100644 (file)
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -14,6 +14,7 @@
 #include <linux/platform_data/cros_usbpd_notify.h>
 #include <linux/platform_device.h>
 #include <linux/usb/typec.h>
+#include <linux/usb/typec_altmode.h>
 #include <linux/usb/typec_mux.h>
 #include <linux/usb/role.h>
 
@@ -30,6 +31,10 @@ struct cros_typec_port {
        struct typec_switch *ori_sw;
        struct typec_mux *mux;
        struct usb_role_switch *role_sw;
+
+       /* Variables keeping track of switch state. */
+       struct typec_mux_state state;
+       uint8_t mux_flags;
 };
 
 /* Platform-specific data for the Chrome OS EC Type C controller. */
@@ -264,6 +269,23 @@ static int cros_typec_add_partner(struct cros_typec_data *typec, int port_num,
        return ret;
 }
 
+static void cros_typec_remove_partner(struct cros_typec_data *typec,
+                                    int port_num)
+{
+       struct cros_typec_port *port = typec->ports[port_num];
+
+       port->state.alt = NULL;
+       port->state.mode = TYPEC_STATE_USB;
+       port->state.data = NULL;
+
+       usb_role_switch_set_role(port->role_sw, USB_ROLE_NONE);
+       typec_switch_set(port->ori_sw, TYPEC_ORIENTATION_NONE);
+       typec_mux_set(port->mux, &port->state);
+
+       typec_unregister_partner(port->partner);
+       port->partner = NULL;
+}
+
 static void cros_typec_set_port_params_v0(struct cros_typec_data *typec,
                int port_num, struct ec_response_usb_pd_control *resp)
 {
@@ -317,16 +339,69 @@ static void cros_typec_set_port_params_v1(struct cros_typec_data *typec,
        } else {
                if (!typec->ports[port_num]->partner)
                        return;
+               cros_typec_remove_partner(typec, port_num);
+       }
+}
+
+static int cros_typec_get_mux_info(struct cros_typec_data *typec, int port_num,
+                                  struct ec_response_usb_pd_mux_info *resp)
+{
+       struct ec_params_usb_pd_mux_info req = {
+               .port = port_num,
+       };
+
+       return cros_typec_ec_command(typec, 0, EC_CMD_USB_PD_MUX_INFO, &req,
+                                    sizeof(req), resp, sizeof(*resp));
+}
+
+static int cros_typec_usb_safe_state(struct cros_typec_port *port)
+{
+       port->state.mode = TYPEC_STATE_SAFE;
+
+       return typec_mux_set(port->mux, &port->state);
+}
 
-               typec_unregister_partner(typec->ports[port_num]->partner);
-               typec->ports[port_num]->partner = NULL;
+int cros_typec_configure_mux(struct cros_typec_data *typec, int port_num,
+                            uint8_t mux_flags)
+{
+       struct cros_typec_port *port = typec->ports[port_num];
+       enum typec_orientation orientation;
+       int ret;
+
+       if (!port->partner)
+               return 0;
+
+       if (mux_flags & USB_PD_MUX_POLARITY_INVERTED)
+               orientation = TYPEC_ORIENTATION_REVERSE;
+       else
+               orientation = TYPEC_ORIENTATION_NORMAL;
+
+       ret = typec_switch_set(port->ori_sw, orientation);
+       if (ret)
+               return ret;
+
+       port->state.alt = NULL;
+       port->state.mode = TYPEC_STATE_USB;
+
+       if (mux_flags & USB_PD_MUX_SAFE_MODE)
+               ret = cros_typec_usb_safe_state(port);
+       else if (mux_flags & USB_PD_MUX_USB_ENABLED)
+               ret = typec_mux_set(port->mux, &port->state);
+       else {
+               dev_info(typec->dev,
+                        "Unsupported mode requested, mux flags: %x\n",
+                        mux_flags);
+               ret = -ENOTSUPP;
        }
+
+       return ret;
 }
 
 static int cros_typec_port_update(struct cros_typec_data *typec, int port_num)
 {
        struct ec_params_usb_pd_control req;
        struct ec_response_usb_pd_control_v1 resp;
+       struct ec_response_usb_pd_mux_info mux_resp;
        int ret;
 
        if (port_num < 0 || port_num >= typec->num_ports) {
@@ -357,7 +432,26 @@ static int cros_typec_port_update(struct cros_typec_data *typec, int port_num)
                cros_typec_set_port_params_v0(typec, port_num,
                        (struct ec_response_usb_pd_control *) &resp);
 
-       return 0;
+       /* Update the switches if they exist, according to requested state */
+       ret = cros_typec_get_mux_info(typec, port_num, &mux_resp);
+       if (ret < 0) {
+               dev_warn(typec->dev,
+                        "Failed to get mux info for port: %d, err = %d\n",
+                        port_num, ret);
+               return 0;
+       }
+
+       /* No change needs to be made, let's exit early. */
+       if (typec->ports[port_num]->mux_flags == mux_resp.flags)
+               return 0;
+
+       typec->ports[port_num]->mux_flags = mux_resp.flags;
+       ret = cros_typec_configure_mux(typec, port_num, mux_resp.flags);
+       if (ret)
+               dev_warn(typec->dev, "Configure muxes failed, err = %d\n", ret);
+
+       return usb_role_switch_set_role(typec->ports[port_num]->role_sw,
+                                       !!(resp.role & PD_CTRL_RESP_ROLE_DATA));
 }
 
 static int cros_typec_get_cmd_version(struct cros_typec_data *typec)