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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /Documentation/driver-api/usb/typec.rst | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to 'Documentation/driver-api/usb/typec.rst')
-rw-r--r-- | Documentation/driver-api/usb/typec.rst | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/Documentation/driver-api/usb/typec.rst b/Documentation/driver-api/usb/typec.rst new file mode 100644 index 000000000..201163d8c --- /dev/null +++ b/Documentation/driver-api/usb/typec.rst @@ -0,0 +1,234 @@ +.. _typec: + +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/class.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/class.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/class.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/class.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/class.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/class.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/class.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/class.c + :functions: typec_partner_register_altmode + +API for the Cable Plugs: + +.. kernel-doc:: drivers/usb/typec/class.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/class.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/class.c + :functions: typec_altmode_update_active + +Multiplexer/DeMultiplexer Switches +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +USB Type-C connectors may have one or more mux/demux switches behind them. Since +the plugs can be inserted right-side-up or upside-down, a switch is needed to +route the correct data pairs from the connector to the USB controllers. If +Alternate or Accessory Modes are supported, another switch is needed that can +route the pins on the connector to some other component besides USB. USB Type-C +Connector Class supplies an API for registering those switches. + +.. kernel-doc:: drivers/usb/typec/mux.c + :functions: typec_switch_register typec_switch_unregister typec_mux_register typec_mux_unregister + +In most cases the same physical mux will handle both the orientation and mode. +However, as the port drivers will be responsible for the orientation, and the +alternate mode drivers for the mode, the two are always separated into their +own logical components: "mux" for the mode and "switch" for the orientation. + +When a port is registered, USB Type-C Connector Class requests both the mux and +the switch for the port. The drivers can then use the following API for +controlling them: + +.. kernel-doc:: drivers/usb/typec/class.c + :functions: typec_set_orientation typec_set_mode + +If the connector is dual-role capable, there may also be a switch for the data +role. USB Type-C Connector Class does not supply separate API for them. The +port drivers can use USB Role Class API with those. + +Illustration of the muxes behind a connector that supports an alternate mode:: + + ------------------------ + | Connector | + ------------------------ + | | + ------------------------ + \ Orientation / + -------------------- + | + -------------------- + / Mode \ + ------------------------ + / \ + ------------------------ -------------------- + | Alt Mode | / USB Role \ + ------------------------ ------------------------ + / \ + ------------------------ ------------------------ + | USB Host | | USB Device | + ------------------------ ------------------------ |