Commit fab92884 authored by Heikki Krogerus's avatar Heikki Krogerus Committed by Greg Kroah-Hartman

usb: USB Type-C connector class

The purpose of USB Type-C connector class is to provide
unified interface for the user space to get the status and
basic information about USB Type-C connectors on a system,
control over data role swapping, and when the port supports
USB Power Delivery, also control over power role swapping
and Alternate Modes.
Signed-off-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-and-Tested-by: default avatarFelipe Balbi <felipe.balbi@linux.intel.com>
Tested-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent e1fe7b6a
This diff is collapsed.
USB Type-C connector class
==========================
Introduction
------------
The typec class is meant for describing the USB Type-C ports in a system to the
user space in unified fashion. The class is designed to provide nothing else
except the user space interface implementation in hope that it can be utilized
on as many platforms as possible.
The platforms are expected to register every USB Type-C port they have with the
class. In a normal case the registration will be done by a USB Type-C or PD PHY
driver, but it may be a driver for firmware interface such as UCSI, driver for
USB PD controller or even driver for Thunderbolt3 controller. This document
considers the component registering the USB Type-C ports with the class as "port
driver".
On top of showing the capabilities, the class also offer user space control over
the roles and alternate modes of ports, partners and cable plugs when the port
driver is capable of supporting those features.
The class provides an API for the port drivers described in this document. The
attributes are described in Documentation/ABI/testing/sysfs-class-typec.
User space interface
--------------------
Every port will be presented as its own device under /sys/class/typec/. The
first port will be named "port0", the second "port1" and so on.
When connected, the partner will be presented also as its own device under
/sys/class/typec/. The parent of the partner device will always be the port it
is attached to. The partner attached to port "port0" will be named
"port0-partner". Full path to the device would be
/sys/class/typec/port0/port0-partner/.
The cable and the two plugs on it may also be optionally presented as their own
devices under /sys/class/typec/. The cable attached to the port "port0" port
will be named port0-cable and the plug on the SOP Prime end (see USB Power
Delivery Specification ch. 2.4) will be named "port0-plug0" and on the SOP
Double Prime end "port0-plug1". The parent of a cable will always be the port,
and the parent of the cable plugs will always be the cable.
If the port, partner or cable plug supports Alternate Modes, every supported
Alternate Mode SVID will have their own device describing them. Note that the
Alternate Mode devices will not be attached to the typec class. The parent of an
alternate mode will be the device that supports it, so for example an alternate
mode of port0-partner will be presented under /sys/class/typec/port0-partner/.
Every mode that is supported will have its own group under the Alternate Mode
device named "mode<index>", for example /sys/class/typec/port0/<alternate
mode>/mode1/. The requests for entering/exiting a mode can be done with "active"
attribute file in that group.
Driver API
----------
Registering the ports
~~~~~~~~~~~~~~~~~~~~~
The port drivers will describe every Type-C port they control with struct
typec_capability data structure, and register them with the following API:
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_register_port typec_unregister_port
When registering the ports, the prefer_role member in struct typec_capability
deserves special notice. If the port that is being registered does not have
initial role preference, which means the port does not execute Try.SNK or
Try.SRC by default, the member must have value TYPEC_NO_PREFERRED_ROLE.
Otherwise if the port executes Try.SNK by default, the member must have value
TYPEC_DEVICE, and with Try.SRC the value must be TYPEC_HOST.
Registering Partners
~~~~~~~~~~~~~~~~~~~~
After successful connection of a partner, the port driver needs to register the
partner with the class. Details about the partner need to be described in struct
typec_partner_desc. The class copies the details of the partner during
registration. The class offers the following API for registering/unregistering
partners.
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_register_partner typec_unregister_partner
The class will provide a handle to struct typec_partner if the registration was
successful, or NULL.
If the partner is USB Power Delivery capable, and the port driver is able to
show the result of Discover Identity command, the partner descriptor structure
should include handle to struct usb_pd_identity instance. The class will then
create a sysfs directory for the identity under the partner device. The result
of Discover Identity command can then be reported with the following API:
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_partner_set_identity
Registering Cables
~~~~~~~~~~~~~~~~~~
After successful connection of a cable that supports USB Power Delivery
Structured VDM "Discover Identity", the port driver needs to register the cable
and one or two plugs, depending if there is CC Double Prime controller present
in the cable or not. So a cable capable of SOP Prime communication, but not SOP
Double Prime communication, should only have one plug registered. For more
information about SOP communication, please read chapter about it from the
latest USB Power Delivery specification.
The plugs are represented as their own devices. The cable is registered first,
followed by registration of the cable plugs. The cable will be the parent device
for the plugs. Details about the cable need to be described in struct
typec_cable_desc and about a plug in struct typec_plug_desc. The class copies
the details during registration. The class offers the following API for
registering/unregistering cables and their plugs:
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_register_cable typec_unregister_cable typec_register_plug
typec_unregister_plug
The class will provide a handle to struct typec_cable and struct typec_plug if
the registration is successful, or NULL if it isn't.
If the cable is USB Power Delivery capable, and the port driver is able to show
the result of Discover Identity command, the cable descriptor structure should
include handle to struct usb_pd_identity instance. The class will then create a
sysfs directory for the identity under the cable device. The result of Discover
Identity command can then be reported with the following API:
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_cable_set_identity
Notifications
~~~~~~~~~~~~~
When the partner has executed a role change, or when the default roles change
during connection of a partner or cable, the port driver must use the following
APIs to report it to the class:
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_set_data_role typec_set_pwr_role typec_set_vconn_role
typec_set_pwr_opmode
Alternate Modes
~~~~~~~~~~~~~~~
USB Type-C ports, partners and cable plugs may support Alternate Modes. Each
Alternate Mode will have identifier called SVID, which is either a Standard ID
given by USB-IF or vendor ID, and each supported SVID can have 1 - 6 modes. The
class provides struct typec_mode_desc for describing individual mode of a SVID,
and struct typec_altmode_desc which is a container for all the supported modes.
Ports that support Alternate Modes need to register each SVID they support with
the following API:
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_port_register_altmode
If a partner or cable plug provides a list of SVIDs as response to USB Power
Delivery Structured VDM Discover SVIDs message, each SVID needs to be
registered.
API for the partners:
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_partner_register_altmode
API for the Cable Plugs:
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_plug_register_altmode
So ports, partners and cable plugs will register the alternate modes with their
own functions, but the registration will always return a handle to struct
typec_altmode on success, or NULL. The unregistration will happen with the same
function:
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_unregister_altmode
If a partner or cable plug enters or exits a mode, the port driver needs to
notify the class with the following API:
.. kernel-doc:: drivers/usb/typec/typec.c
:functions: typec_altmode_update_active
...@@ -13100,6 +13100,15 @@ F: drivers/usb/ ...@@ -13100,6 +13100,15 @@ F: drivers/usb/
F: include/linux/usb.h F: include/linux/usb.h
F: include/linux/usb/ F: include/linux/usb/
USB TYPEC SUBSYSTEM
M: Heikki Krogerus <heikki.krogerus@linux.intel.com>
L: linux-usb@vger.kernel.org
S: Maintained
F: Documentation/ABI/testing/sysfs-class-typec
F: Documentation/usb/typec.rst
F: drivers/usb/typec/
F: include/linux/usb/typec.h
USB UHCI DRIVER USB UHCI DRIVER
M: Alan Stern <stern@rowland.harvard.edu> M: Alan Stern <stern@rowland.harvard.edu>
L: linux-usb@vger.kernel.org L: linux-usb@vger.kernel.org
......
...@@ -162,6 +162,8 @@ source "drivers/usb/phy/Kconfig" ...@@ -162,6 +162,8 @@ source "drivers/usb/phy/Kconfig"
source "drivers/usb/gadget/Kconfig" source "drivers/usb/gadget/Kconfig"
source "drivers/usb/typec/Kconfig"
config USB_LED_TRIG config USB_LED_TRIG
bool "USB LED Triggers" bool "USB LED Triggers"
depends on LEDS_CLASS && LEDS_TRIGGERS depends on LEDS_CLASS && LEDS_TRIGGERS
......
...@@ -62,3 +62,5 @@ obj-$(CONFIG_USB_GADGET) += gadget/ ...@@ -62,3 +62,5 @@ obj-$(CONFIG_USB_GADGET) += gadget/
obj-$(CONFIG_USB_COMMON) += common/ obj-$(CONFIG_USB_COMMON) += common/
obj-$(CONFIG_USBIP_CORE) += usbip/ obj-$(CONFIG_USBIP_CORE) += usbip/
obj-$(CONFIG_TYPEC) += typec/
menu "USB Power Delivery and Type-C drivers"
config TYPEC
tristate
endmenu
obj-$(CONFIG_TYPEC) += typec.o
This diff is collapsed.
#ifndef __LINUX_USB_TYPEC_H
#define __LINUX_USB_TYPEC_H
#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;
enum typec_port_type {
TYPEC_PORT_DFP,
TYPEC_PORT_UFP,
TYPEC_PORT_DRP,
};
enum typec_plug_type {
USB_PLUG_NONE,
USB_PLUG_TYPE_A,
USB_PLUG_TYPE_B,
USB_PLUG_TYPE_C,
USB_PLUG_CAPTIVE,
};
enum typec_data_role {
TYPEC_DEVICE,
TYPEC_HOST,
};
enum typec_role {
TYPEC_SINK,
TYPEC_SOURCE,
};
enum typec_pwr_opmode {
TYPEC_PWR_MODE_USB,
TYPEC_PWR_MODE_1_5A,
TYPEC_PWR_MODE_3_0A,
TYPEC_PWR_MODE_PD,
};
enum typec_accessory {
TYPEC_ACCESSORY_NONE,
TYPEC_ACCESSORY_AUDIO,
TYPEC_ACCESSORY_DEBUG,
};
#define TYPEC_MAX_ACCESSORY 3
/*
* struct usb_pd_identity - USB Power Delivery identity data
* @id_header: ID Header VDO
* @cert_stat: Cert Stat VDO
* @product: Product VDO
*
* USB power delivery Discover Identity command response data.
*
* REVISIT: This is USB Power Delivery specific information, so this structure
* probable belongs to USB Power Delivery header file once we have them.
*/
struct usb_pd_identity {
u32 id_header;
u32 cert_stat;
u32 product;
};
int typec_partner_set_identity(struct typec_partner *partner);
int typec_cable_set_identity(struct typec_cable *cable);
/*
* struct typec_mode_desc - Individual Mode of an Alternate Mode
* @index: Index of the Mode within the SVID
* @vdo: VDO returned by Discover Modes USB PD command
* @desc: Optional human readable description of the mode
* @roles: Only for ports. DRP if the mode is available in both roles
*
* Description of a mode of an Alternate Mode which a connector, cable plug or
* partner supports. Every mode will have it's own sysfs group. The details are
* the VDO returned by discover modes command, description for the mode and
* active flag telling has the mode being entered or not.
*/
struct typec_mode_desc {
int index;
u32 vdo;
char *desc;
/* Only used with ports */
enum typec_port_type roles;
};
/*
* struct typec_altmode_desc - USB Type-C Alternate Mode Descriptor
* @svid: Standard or Vendor ID
* @n_modes: Number of modes
* @modes: Array of modes supported by the Alternate Mode
*
* Representation of an Alternate Mode that has SVID assigned by USB-IF. The
* array of modes will list the modes of a particular SVID that are supported by
* a connector, partner of a cable plug.
*/
struct typec_altmode_desc {
u16 svid;
int n_modes;
struct typec_mode_desc modes[ALTMODE_MAX_MODES];
};
struct typec_altmode
*typec_partner_register_altmode(struct typec_partner *partner,
struct typec_altmode_desc *desc);
struct typec_altmode
*typec_plug_register_altmode(struct typec_plug *plug,
struct typec_altmode_desc *desc);
struct typec_altmode
*typec_port_register_altmode(struct typec_port *port,
struct typec_altmode_desc *desc);
void typec_unregister_altmode(struct typec_altmode *altmode);
struct typec_port *typec_altmode2port(struct typec_altmode *alt);
void typec_altmode_update_active(struct typec_altmode *alt, int mode,
bool active);
enum typec_plug_index {
TYPEC_PLUG_SOP_P,
TYPEC_PLUG_SOP_PP,
};
/*
* struct typec_plug_desc - USB Type-C Cable Plug Descriptor
* @index: SOP Prime for the plug connected to DFP and SOP Double Prime for the
* plug connected to UFP
*
* Represents USB Type-C Cable Plug.
*/
struct typec_plug_desc {
enum typec_plug_index index;
};
/*
* struct typec_cable_desc - USB Type-C Cable Descriptor
* @type: The plug type from USB PD Cable VDO
* @active: Is the cable active or passive
* @identity: Result of Discover Identity command
*
* Represents USB Type-C Cable attached to USB Type-C port.
*/
struct typec_cable_desc {
enum typec_plug_type type;
unsigned int active:1;
struct usb_pd_identity *identity;
};
/*
* struct typec_partner_desc - USB Type-C Partner Descriptor
* @usb_pd: USB Power Delivery support
* @accessory: Audio, Debug or none.
* @identity: Discover Identity command data
*
* Details about a partner that is attached to USB Type-C port. If @identity
* member exists when partner is registered, a directory named "identity" is
* created to sysfs for the partner device.
*/
struct typec_partner_desc {
unsigned int usb_pd:1;
enum typec_accessory accessory;
struct usb_pd_identity *identity;
};
/*
* struct typec_capability - USB Type-C Port Capabilities
* @role: DFP (Host-only), UFP (Device-only) or DRP (Dual Role)
* @revision: USB Type-C Specification release. Binary coded decimal
* @pd_revision: USB Power Delivery Specification revision if supported
* @prefer_role: Initial role preference
* @accessory: Supported Accessory Modes
* @fwnode: Optional fwnode of the port
* @try_role: Set data role preference for DRP port
* @dr_set: Set Data Role
* @pr_set: Set Power Role
* @vconn_set: Set VCONN Role
* @activate_mode: Enter/exit given Alternate Mode
*
* Static capabilities of a single USB Type-C port.
*/
struct typec_capability {
enum typec_port_type type;
u16 revision; /* 0120H = "1.2" */
u16 pd_revision; /* 0300H = "3.0" */
int prefer_role;
enum typec_accessory accessory[TYPEC_MAX_ACCESSORY];
struct fwnode_handle *fwnode;
int (*try_role)(const struct typec_capability *,
int role);
int (*dr_set)(const struct typec_capability *,
enum typec_data_role);
int (*pr_set)(const 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);
};
/* Specific to try_role(). Indicates the user want's to clear the preference. */
#define TYPEC_NO_PREFERRED_ROLE (-1)
struct typec_port *typec_register_port(struct device *parent,
const struct typec_capability *cap);
void typec_unregister_port(struct typec_port *port);
struct typec_partner *typec_register_partner(struct typec_port *port,
struct typec_partner_desc *desc);
void typec_unregister_partner(struct typec_partner *partner);
struct typec_cable *typec_register_cable(struct typec_port *port,
struct typec_cable_desc *desc);
void typec_unregister_cable(struct typec_cable *cable);
struct typec_plug *typec_register_plug(struct typec_cable *cable,
struct typec_plug_desc *desc);
void typec_unregister_plug(struct typec_plug *plug);
void typec_set_data_role(struct typec_port *port, enum typec_data_role role);
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);
#endif /* __LINUX_USB_TYPEC_H */
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