usb: typec: Bus type for alternate modes

Introducing a simple bus for the alternate modes. Bus allows
binding drivers to the discovered alternate modes the
partners support.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 178 insertions, 11 deletions

diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index 96a71a648eed..1298a7daa57d 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -746,4 +746,19 @@ struct tb_service_id {
 #define TBSVC_MATCH_PROTOCOL_VERSION    0x0004
 #define TBSVC_MATCH_PROTOCOL_REVISION   0x0008
 
+/* USB Type-C Alternate Modes */
+
+#define TYPEC_ANY_MODE  0x7
+
+/**
+ * struct typec_device_id - USB Type-C alternate mode identifiers
+ * @svid: Standard or Vendor ID
+ * @mode: Mode index
+ */
+struct typec_device_id {
+        __u16 svid;
+        __u8 mode;
+        kernel_ulong_t driver_data;
+};
+
 #endif /* LINUX_MOD_DEVICETABLE_H */
diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h
index 2dcb1683075f..7df4ecabc78a 100644
--- a/include/linux/usb/typec.h
+++ b/include/linux/usb/typec.h
@@ -5,21 +5,18 @@
 
 #include <linux/types.h>
 
-/* XXX: Once we have a header for USB Power Delivery, this belongs there */
-#define ALTMODE_MAX_MODES       6
-
 /* USB Type-C Specification releases */
 #define USB_TYPEC_REV_1_0       0x100 /* 1.0 */
 #define USB_TYPEC_REV_1_1       0x110 /* 1.1 */
 #define USB_TYPEC_REV_1_2       0x120 /* 1.2 */
 
-struct typec_altmode;
 struct typec_partner;
 struct typec_cable;
 struct typec_plug;
 struct typec_port;
 
 struct fwnode_handle;
+struct device;
 
 enum typec_port_type {
         TYPEC_PORT_SRC,
@@ -107,7 +104,7 @@ struct typec_altmode_desc {
         u8                      mode;
         u32                     vdo;
         /* Only used with ports */
-        enum typec_port_type    roles;
+        enum typec_port_data    roles;
 };
 
 struct typec_altmode
@@ -186,7 +183,6 @@ struct typec_partner_desc {
  * @dr_set: Set Data Role
  * @pr_set: Set Power Role
  * @vconn_set: Set VCONN Role
- * @activate_mode: Enter/exit given Alternate Mode
  * @port_type_set: Set port type
  *
  * Static capabilities of a single USB Type-C port.
@@ -212,12 +208,8 @@ struct typec_capability {
                                   enum typec_role);
         int             (*vconn_set)(const struct typec_capability *,
                                      enum typec_role);
-
-        int             (*activate_mode)(const struct typec_capability *,
-                                         int mode, int activate);
         int             (*port_type_set)(const struct typec_capability *,
-                                        enum typec_port_type);
-
+                                         enum typec_port_type);
 };
 
 /* Specific to try_role(). Indicates the user want's to clear the preference. */
diff --git a/include/linux/usb/typec_altmode.h b/include/linux/usb/typec_altmode.h
new file mode 100644
index 000000000000..9a88c74a1d0d
--- /dev/null
+++ b/include/linux/usb/typec_altmode.h
@@ -0,0 +1,160 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __USB_TYPEC_ALTMODE_H
+#define __USB_TYPEC_ALTMODE_H
+
+#include <linux/mod_devicetable.h>
+#include <linux/usb/typec.h>
+#include <linux/device.h>
+
+#define MODE_DISCOVERY_MAX      6
+
+struct typec_altmode_ops;
+
+/**
+ * struct typec_altmode - USB Type-C alternate mode device
+ * @dev: Driver model's view of this device
+ * @svid: Standard or Vendor ID (SVID) of the alternate mode
+ * @mode: Index of the Mode
+ * @vdo: VDO returned by Discover Modes USB PD command
+ * @active: Tells has the mode been entered or not
+ * @desc: Optional human readable description of the mode
+ * @ops: Operations vector from the driver
+ */
+struct typec_altmode {
+        struct device                   dev;
+        u16                             svid;
+        int                             mode;
+        u32                             vdo;
+        unsigned int                    active:1;
+
+        char                            *desc;
+        const struct typec_altmode_ops  *ops;
+};
+
+#define to_typec_altmode(d) container_of(d, struct typec_altmode, dev)
+
+static inline void typec_altmode_set_drvdata(struct typec_altmode *altmode,
+                                             void *data)
+{
+        dev_set_drvdata(&altmode->dev, data);
+}
+
+static inline void *typec_altmode_get_drvdata(struct typec_altmode *altmode)
+{
+        return dev_get_drvdata(&altmode->dev);
+}
+
+/**
+ * struct typec_altmode_ops - Alternate mode specific operations vector
+ * @enter: Operations to be executed with Enter Mode Command
+ * @exit: Operations to be executed with Exit Mode Command
+ * @attention: Callback for Attention Command
+ * @vdm: Callback for SVID specific commands
+ * @notify: Communication channel for platform and the alternate mode
+ * @activate: User callback for Enter/Exit Mode
+ */
+struct typec_altmode_ops {
+        int (*enter)(struct typec_altmode *altmode);
+        int (*exit)(struct typec_altmode *altmode);
+        void (*attention)(struct typec_altmode *altmode, u32 vdo);
+        int (*vdm)(struct typec_altmode *altmode, const u32 hdr,
+                   const u32 *vdo, int cnt);
+        int (*notify)(struct typec_altmode *altmode, unsigned long conf,
+                      void *data);
+        int (*activate)(struct typec_altmode *altmode, int activate);
+};
+
+int typec_altmode_enter(struct typec_altmode *altmode);
+int typec_altmode_exit(struct typec_altmode *altmode);
+void typec_altmode_attention(struct typec_altmode *altmode, u32 vdo);
+int typec_altmode_vdm(struct typec_altmode *altmode,
+                      const u32 header, const u32 *vdo, int count);
+int typec_altmode_notify(struct typec_altmode *altmode, unsigned long conf,
+                         void *data);
+const struct typec_altmode *
+typec_altmode_get_partner(struct typec_altmode *altmode);
+
+/*
+ * These are the connector states (USB, Safe and Alt Mode) defined in USB Type-C
+ * Specification. SVID specific connector states are expected to follow and
+ * start from the value TYPEC_STATE_MODAL.
+ */
+enum {
+        TYPEC_STATE_SAFE,       /* USB Safe State */
+        TYPEC_STATE_USB,        /* USB Operation */
+        TYPEC_STATE_MODAL,      /* Alternate Modes */
+};
+
+/*
+ * For the muxes there is no difference between Accessory Modes and Alternate
+ * Modes, so the Accessory Modes are supplied with specific modal state values
+ * here. Unlike with Alternate Modes, where the mux will be linked with the
+ * alternate mode device, the mux for Accessory Modes will be linked with the
+ * port device instead.
+ *
+ * Port drivers can use TYPEC_MODE_AUDIO and TYPEC_MODE_DEBUG as the mode
+ * value for typec_set_mode() when accessory modes are supported.
+ */
+enum {
+        TYPEC_MODE_AUDIO = TYPEC_STATE_MODAL,   /* Audio Accessory */
+        TYPEC_MODE_DEBUG,                       /* Debug Accessory */
+};
+
+#define TYPEC_MODAL_STATE(_state_)      ((_state_) + TYPEC_STATE_MODAL)
+
+struct typec_altmode *typec_altmode_get_plug(struct typec_altmode *altmode,
+                                             enum typec_plug_index index);
+void typec_altmode_put_plug(struct typec_altmode *plug);
+
+struct typec_altmode *typec_match_altmode(struct typec_altmode **altmodes,
+                                          size_t n, u16 svid, u8 mode);
+
+struct typec_altmode *
+typec_altmode_register_notifier(struct device *dev, u16 svid, u8 mode,
+                                struct notifier_block *nb);
+
+void typec_altmode_unregister_notifier(struct typec_altmode *adev,
+                                       struct notifier_block *nb);
+
+/**
+ * typec_altmode_get_orientation - Get cable plug orientation
+ * altmode: Handle to the alternate mode
+ */
+static inline enum typec_orientation
+typec_altmode_get_orientation(struct typec_altmode *altmode)
+{
+        return typec_get_orientation(typec_altmode2port(altmode));
+}
+
+/**
+ * struct typec_altmode_driver - USB Type-C alternate mode device driver
+ * @id_table: Null terminated array of SVIDs
+ * @probe: Callback for device binding
+ * @remove: Callback for device unbinding
+ * @driver: Device driver model driver
+ *
+ * These drivers will be bind to the partner alternate mode devices. They will
+ * handle all SVID specific communication.
+ */
+struct typec_altmode_driver {
+        const struct typec_device_id *id_table;
+        int (*probe)(struct typec_altmode *altmode);
+        void (*remove)(struct typec_altmode *altmode);
+        struct device_driver driver;
+};
+
+#define to_altmode_driver(d) container_of(d, struct typec_altmode_driver, \
+                                          driver)
+
+#define typec_altmode_register_driver(drv) \
+                __typec_altmode_register_driver(drv, THIS_MODULE)
+int __typec_altmode_register_driver(struct typec_altmode_driver *drv,
+                                    struct module *module);
+void typec_altmode_unregister_driver(struct typec_altmode_driver *drv);
+
+#define module_typec_altmode_driver(__typec_altmode_driver) \
+        module_driver(__typec_altmode_driver, typec_altmode_register_driver, \
+                      typec_altmode_unregister_driver)
+
+#endif /* __USB_TYPEC_ALTMODE_H */