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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
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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(). ...
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+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. c:namespace:: V4L
+
+.. _rds:
+
+*************
+RDS Interface
+*************
+
+The Radio Data System transmits supplementary information in binary
+format, for example the station name or travel information, on an
+inaudible audio subcarrier of a radio program. This interface is aimed
+at devices capable of receiving and/or transmitting RDS information.
+
+For more information see the core RDS standard :ref:`iec62106` and the
+RBDS standard :ref:`nrsc4`.
+
+.. note::
+
+ Note that the RBDS standard as is used in the USA is almost
+ identical to the RDS standard. Any RDS decoder/encoder can also handle
+ RBDS. Only some of the fields have slightly different meanings. See the
+ RBDS standard for more information.
+
+The RBDS standard also specifies support for MMBS (Modified Mobile
+Search). This is a proprietary format which seems to be discontinued.
+The RDS interface does not support this format. Should support for MMBS
+(or the so-called 'E blocks' in general) be needed, then please contact
+the linux-media mailing list:
+`https://linuxtv.org/lists.php <https://linuxtv.org/lists.php>`__.
+
+Querying Capabilities
+=====================
+
+Devices supporting the RDS capturing API set the
+``V4L2_CAP_RDS_CAPTURE`` flag in the ``capabilities`` field of struct
+:c:type:`v4l2_capability` returned by the
+:ref:`VIDIOC_QUERYCAP` ioctl. Any tuner that
+supports RDS will set the ``V4L2_TUNER_CAP_RDS`` flag in the
+``capability`` field of struct :c:type:`v4l2_tuner`. If the
+driver only passes RDS blocks without interpreting the data the
+``V4L2_TUNER_CAP_RDS_BLOCK_IO`` flag has to be set, see
+:ref:`Reading RDS data <reading-rds-data>`. For future use the flag
+``V4L2_TUNER_CAP_RDS_CONTROLS`` has also been defined. However, a driver
+for a radio tuner with this capability does not yet exist, so if you are
+planning to write such a driver you should discuss this on the
+linux-media mailing list:
+`https://linuxtv.org/lists.php <https://linuxtv.org/lists.php>`__.
+
+Whether an RDS signal is present can be detected by looking at the
+``rxsubchans`` field of struct :c:type:`v4l2_tuner`: the
+``V4L2_TUNER_SUB_RDS`` will be set if RDS data was detected.
+
+Devices supporting the RDS output API set the ``V4L2_CAP_RDS_OUTPUT``
+flag in the ``capabilities`` field of struct
+:c:type:`v4l2_capability` returned by the
+:ref:`VIDIOC_QUERYCAP` ioctl. Any modulator that
+supports RDS will set the ``V4L2_TUNER_CAP_RDS`` flag in the
+``capability`` field of struct
+:c:type:`v4l2_modulator`. In order to enable the RDS
+transmission one must set the ``V4L2_TUNER_SUB_RDS`` bit in the
+``txsubchans`` field of struct
+:c:type:`v4l2_modulator`. If the driver only passes RDS
+blocks without interpreting the data the ``V4L2_TUNER_CAP_RDS_BLOCK_IO``
+flag has to be set. If the tuner is capable of handling RDS entities
+like program identification codes and radio text, the flag
+``V4L2_TUNER_CAP_RDS_CONTROLS`` should be set, see
+:ref:`Writing RDS data <writing-rds-data>` and
+:ref:`FM Transmitter Control Reference <fm-tx-controls>`.
+
+.. _reading-rds-data:
+
+Reading RDS data
+================
+
+RDS data can be read from the radio device with the
+:c:func:`read()` function. The data is packed in groups of
+three bytes.
+
+.. _writing-rds-data:
+
+Writing RDS data
+================
+
+RDS data can be written to the radio device with the
+:c:func:`write()` function. The data is packed in groups of
+three bytes, as follows:
+
+RDS datastructures
+==================
+
+.. c:type:: v4l2_rds_data
+
+.. flat-table:: struct v4l2_rds_data
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 5
+
+ * - __u8
+ - ``lsb``
+ - Least Significant Byte of RDS Block
+ * - __u8
+ - ``msb``
+ - Most Significant Byte of RDS Block
+ * - __u8
+ - ``block``
+ - Block description
+
+
+.. _v4l2-rds-block:
+
+.. tabularcolumns:: |p{2.9cm}|p{14.6cm}|
+
+.. flat-table:: Block description
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 5
+
+ * - Bits 0-2
+ - Block (aka offset) of the received data.
+ * - Bits 3-5
+ - Deprecated. Currently identical to bits 0-2. Do not use these
+ bits.
+ * - Bit 6
+ - Corrected bit. Indicates that an error was corrected for this data
+ block.
+ * - Bit 7
+ - Error bit. Indicates that an uncorrectable error occurred during
+ reception of this block.
+
+
+.. _v4l2-rds-block-codes:
+
+.. tabularcolumns:: |p{6.4cm}|p{2.0cm}|p{1.2cm}|p{7.0cm}|
+
+.. flat-table:: Block defines
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 1 5
+
+ * - V4L2_RDS_BLOCK_MSK
+ -
+ - 7
+ - Mask for bits 0-2 to get the block ID.
+ * - V4L2_RDS_BLOCK_A
+ -
+ - 0
+ - Block A.
+ * - V4L2_RDS_BLOCK_B
+ -
+ - 1
+ - Block B.
+ * - V4L2_RDS_BLOCK_C
+ -
+ - 2
+ - Block C.
+ * - V4L2_RDS_BLOCK_D
+ -
+ - 3
+ - Block D.
+ * - V4L2_RDS_BLOCK_C_ALT
+ -
+ - 4
+ - Block C'.
+ * - V4L2_RDS_BLOCK_INVALID
+ - read-only
+ - 7
+ - An invalid block.
+ * - V4L2_RDS_BLOCK_CORRECTED
+ - read-only
+ - 0x40
+ - A bit error was detected but corrected.
+ * - V4L2_RDS_BLOCK_ERROR
+ - read-only
+ - 0x80
+ - An uncorrectable error occurred.