[v1,0/3] usb: typec: Separate sysfs directory for all USB PD objects

Message

Heikki Krogerus Feb. 3, 2022, 2:46 p.m. UTC

Hi,

Ideally after this there should be no need to add any new USB Power
Delivery specific attribute files directly to the USB Type-C devices
in sysfs. They now have their own directory.

The idea of the series is that any device (so not just USB Type-C
connectors and the partners attached to them) that supports USB Power
Delivery can have this separate sub-directory "usb_power_delivery" in
sysfs, and that sub-directory will have all the USB Power Delivery
objects and all the other USB Power Delivery details.

There are already ways that allow us to read the USB Power Delivery
capabilities from potentially any USB PD capable USB device attached
to the bus - one way is defined in the USB Type-C Bridge
Specification.

Initially the Capability Messages (i.e. PDOs) are exposed.

This is an example (tree view) of the capabilities that the ports on a
normal x86 system advertise to the partner. First you have the message
directory (source_capabilities and sink_capabilities), and that will
have a sub-directory for each PDO that capability message has. The PDO
sub-directories are named by their type. The number in front of the
name is the object position of the PDO:

/sys/class/typec/port0/usb_power_delivery
|-- revision
|-- sink_capabilities/
|   |-- 1:fixed_supply/
|   |   |-- dual_role_data
|   |   |-- dual_role_power
|   |   |-- fast_role_swap_current
|   |   |-- operational_current
|   |   |-- unchunked_extended_messages_supported
|   |   |-- unconstrained_power
|   |   |-- usb_communication_capable
|   |   |-- usb_suspend_supported
|   |   `-- voltage
|   |-- 2:variable_supply/
|   |   |-- maximum_voltage
|   |   |-- minimum_voltage
|   |   `-- operational_current
|   `-- 3:battery/
|       |-- maximum_voltage
|       |-- minimum_voltage
|       `-- operational_power
`-- source_capabilities/
    `-- 1:fixed_supply/
        |-- dual_role_data
        |-- dual_role_power
        |-- maximum_current
        |-- unchunked_extended_messages_supported
        |-- unconstrained_power
        |-- usb_communication_capable
        |-- usb_suspend_supported
        `-- voltage

And these are the capabilities of my Thunderbolt3 dock:

/sys/class/typec/port0-partner/usb_power_delivery
|-- revision
|-- sink_capabilities/
|   `-- 1:fixed_supply/
|       |-- dual_role_data
|       |-- dual_role_power
|       |-- fast_role_swap_current
|       |-- operational_current
|       |-- unchunked_extended_messages_supported
|       |-- unconstrained_power
|       |-- usb_communication_capable
|       |-- usb_suspend_supported
|       `-- voltage
`-- source_capabilities/
    |-- 1:fixed_supply/
    |   |-- dual_role_data
    |   |-- dual_role_power
    |   |-- maximum_current
    |   |-- unchunked_extended_messages_supported
    |   |-- unconstrained_power
    |   |-- usb_communication_capable
    |   |-- usb_suspend_supported
    |   `-- voltage
    |-- 2:fixed_supply/
    |   |-- maximum_current
    |   `-- voltage
    |-- 3:fixed_supply/
    |   |-- maximum_current
    |   `-- voltage
    |-- 4:fixed_supply/
    |   |-- maximum_current
    |   `-- voltage
    `-- 5:fixed_supply/
        |-- maximum_current
        `-- voltage

thanks,

Heikki Krogerus (3):
  usb: typec: Separate USB Power Delivery from USB Type-C
  usb: typec: Functions for USB PD capabilities registration
  usb: typec: ucsi: Register USB Power Delivery Capabilities

 Documentation/ABI/testing/sysfs-class-typec   |  22 +
 .../testing/sysfs-devices-usb_power_delivery  | 273 ++++++++
 drivers/usb/typec/Makefile                    |   2 +-
 drivers/usb/typec/class.c                     | 328 +++++++++
 drivers/usb/typec/class.h                     |   8 +
 drivers/usb/typec/pd.c                        | 651 ++++++++++++++++++
 drivers/usb/typec/pd.h                        |  39 ++
 drivers/usb/typec/ucsi/ucsi.c                 | 128 +++-
 drivers/usb/typec/ucsi/ucsi.h                 |   8 +
 include/linux/usb/pd.h                        |  30 +
 include/linux/usb/typec.h                     |  25 +
 11 files changed, 1502 insertions(+), 12 deletions(-)
 create mode 100644 Documentation/ABI/testing/sysfs-devices-usb_power_delivery
 create mode 100644 drivers/usb/typec/pd.c
 create mode 100644 drivers/usb/typec/pd.h