usb: typec: API for controlling USB Type-C Multiplexers

USB Type-C connectors consist of various muxes and switches
that route the pins on the connector to the right locations.
The USB Type-C drivers need to be able to control the muxes,
as they are the ones that know things like the cable plug
orientation, and the current mode that was negotiated with
the partner.

This introduces a small API for registering and controlling
cable plug orientation switches, and separate small API for
registering and controlling pin multiplexer/demultiplexer
switches that are needed with Accessory/Alternate Modes.

Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 69 insertions, 0 deletions

diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h
index 0d44ce6af08f..2408e5c2ed91 100644
--- a/include/linux/usb/typec.h
+++ b/include/linux/usb/typec.h
@@ -60,6 +60,12 @@ enum typec_accessory {
 
 #define TYPEC_MAX_ACCESSORY     3
 
+enum typec_orientation {
+        TYPEC_ORIENTATION_NONE,
+        TYPEC_ORIENTATION_NORMAL,
+        TYPEC_ORIENTATION_REVERSE,
+};
+
 /*
  * struct usb_pd_identity - USB Power Delivery identity data
  * @id_header: ID Header VDO
@@ -185,6 +191,8 @@ struct typec_partner_desc {
  * @pd_revision: USB Power Delivery Specification revision if supported
  * @prefer_role: Initial role preference
  * @accessory: Supported Accessory Modes
+ * @sw: Cable plug orientation switch
+ * @mux: Multiplexer switch for Alternate/Accessory Modes
  * @fwnode: Optional fwnode of the port
  * @try_role: Set data role preference for DRP port
  * @dr_set: Set Data Role
@@ -202,6 +210,8 @@ struct typec_capability {
         int                     prefer_role;
         enum typec_accessory    accessory[TYPEC_MAX_ACCESSORY];
 
+        struct typec_switch     *sw;
+        struct typec_mux        *mux;
         struct fwnode_handle    *fwnode;
 
         int             (*try_role)(const struct typec_capability *,
@@ -245,4 +255,8 @@ void typec_set_pwr_role(struct typec_port *port, enum typec_role role);
 void typec_set_vconn_role(struct typec_port *port, enum typec_role role);
 void typec_set_pwr_opmode(struct typec_port *port, enum typec_pwr_opmode mode);
 
+int typec_set_orientation(struct typec_port *port,
+                          enum typec_orientation orientation);
+int typec_set_mode(struct typec_port *port, int mode);
+
 #endif /* __LINUX_USB_TYPEC_H */
diff --git a/include/linux/usb/typec_mux.h b/include/linux/usb/typec_mux.h
new file mode 100644
index 000000000000..12c1b057834b
--- /dev/null
+++ b/include/linux/usb/typec_mux.h
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#ifndef __USB_TYPEC_MUX
+#define __USB_TYPEC_MUX
+
+#include <linux/list.h>
+#include <linux/usb/typec.h>
+
+struct device;
+
+/**
+ * struct typec_switch - USB Type-C cable orientation switch
+ * @dev: Switch device
+ * @entry: List entry
+ * @set: Callback to the driver for setting the orientation
+ *
+ * USB Type-C pin flipper switch routing the correct data pairs from the
+ * connector to the USB controller depending on the orientation of the cable
+ * plug.
+ */
+struct typec_switch {
+        struct device *dev;
+        struct list_head entry;
+
+        int (*set)(struct typec_switch *sw, enum typec_orientation orientation);
+};
+
+/**
+ * struct typec_switch - USB Type-C connector pin mux
+ * @dev: Mux device
+ * @entry: List entry
+ * @set: Callback to the driver for setting the state of the mux
+ *
+ * Pin Multiplexer/DeMultiplexer switch routing the USB Type-C connector pins to
+ * different components depending on the requested mode of operation. Used with
+ * Accessory/Alternate modes.
+ */
+struct typec_mux {
+        struct device *dev;
+        struct list_head entry;
+
+        int (*set)(struct typec_mux *mux, int state);
+};
+
+struct typec_switch *typec_switch_get(struct device *dev);
+void typec_switch_put(struct typec_switch *sw);
+int typec_switch_register(struct typec_switch *sw);
+void typec_switch_unregister(struct typec_switch *sw);
+
+struct typec_mux *typec_mux_get(struct device *dev);
+void typec_mux_put(struct typec_mux *mux);
+int typec_mux_register(struct typec_mux *mux);
+void typec_mux_unregister(struct typec_mux *mux);
+
+#endif /* __USB_TYPEC_MUX */