From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- .../userspace-api/media/v4l/vidioc-dqevent.rst | 377 +++++++++++++++++++++ 1 file changed, 377 insertions(+) create mode 100644 Documentation/userspace-api/media/v4l/vidioc-dqevent.rst (limited to 'Documentation/userspace-api/media/v4l/vidioc-dqevent.rst') diff --git a/Documentation/userspace-api/media/v4l/vidioc-dqevent.rst b/Documentation/userspace-api/media/v4l/vidioc-dqevent.rst new file mode 100644 index 000000000..8db103760 --- /dev/null +++ b/Documentation/userspace-api/media/v4l/vidioc-dqevent.rst @@ -0,0 +1,377 @@ +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later +.. c:namespace:: V4L + +.. _VIDIOC_DQEVENT: + +******************** +ioctl VIDIOC_DQEVENT +******************** + +Name +==== + +VIDIOC_DQEVENT - Dequeue event + +Synopsis +======== + +.. c:macro:: VIDIOC_DQEVENT + +``int ioctl(int fd, VIDIOC_DQEVENT, struct v4l2_event *argp)`` + +Arguments +========= + +``fd`` + File descriptor returned by :c:func:`open()`. + +``argp`` + Pointer to struct :c:type:`v4l2_event`. + +Description +=========== + +Dequeue an event from a video device. No input is required for this +ioctl. All the fields of the struct :c:type:`v4l2_event` +structure are filled by the driver. The file handle will also receive +exceptions which the application may get by e.g. using the select system +call. + +.. c:type:: v4l2_event + +.. tabularcolumns:: |p{3.0cm}|p{3.4cm}|p{10.9cm}| + + +.. flat-table:: struct v4l2_event + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u32 + - ``type`` + - Type of the event, see :ref:`event-type`. + * - union { + - ``u`` + * - struct :c:type:`v4l2_event_vsync` + - ``vsync`` + - Event data for event ``V4L2_EVENT_VSYNC``. + * - struct :c:type:`v4l2_event_ctrl` + - ``ctrl`` + - Event data for event ``V4L2_EVENT_CTRL``. + * - struct :c:type:`v4l2_event_frame_sync` + - ``frame_sync`` + - Event data for event ``V4L2_EVENT_FRAME_SYNC``. + * - struct :c:type:`v4l2_event_motion_det` + - ``motion_det`` + - Event data for event V4L2_EVENT_MOTION_DET. + * - struct :c:type:`v4l2_event_src_change` + - ``src_change`` + - Event data for event V4L2_EVENT_SOURCE_CHANGE. + * - __u8 + - ``data``\ [64] + - Event data. Defined by the event type. The union should be used to + define easily accessible type for events. + * - } + - + * - __u32 + - ``pending`` + - Number of pending events excluding this one. + * - __u32 + - ``sequence`` + - Event sequence number. The sequence number is incremented for + every subscribed event that takes place. If sequence numbers are + not contiguous it means that events have been lost. + * - struct timespec + - ``timestamp`` + - Event timestamp. The timestamp has been taken from the + ``CLOCK_MONOTONIC`` clock. To access the same clock outside V4L2, + use :c:func:`clock_gettime`. + * - u32 + - ``id`` + - The ID associated with the event source. If the event does not + have an associated ID (this depends on the event type), then this + is 0. + * - __u32 + - ``reserved``\ [8] + - Reserved for future extensions. Drivers must set the array to + zero. + + +.. tabularcolumns:: |p{6.2cm}|p{2.6cm}|p{8.5cm}| + +.. cssclass:: longtable + +.. _event-type: + +.. flat-table:: Event Types + :header-rows: 0 + :stub-columns: 0 + :widths: 3 1 4 + + * - ``V4L2_EVENT_ALL`` + - 0 + - All events. V4L2_EVENT_ALL is valid only for + VIDIOC_UNSUBSCRIBE_EVENT for unsubscribing all events at once. + * - ``V4L2_EVENT_VSYNC`` + - 1 + - This event is triggered on the vertical sync. This event has a + struct :c:type:`v4l2_event_vsync` associated + with it. + * - ``V4L2_EVENT_EOS`` + - 2 + - This event is triggered when the end of a stream is reached. This + is typically used with MPEG decoders to report to the application + when the last of the MPEG stream has been decoded. + * - ``V4L2_EVENT_CTRL`` + - 3 + - This event requires that the ``id`` matches the control ID from + which you want to receive events. This event is triggered if the + control's value changes, if a button control is pressed or if the + control's flags change. This event has a struct + :c:type:`v4l2_event_ctrl` associated with it. + This struct contains much of the same information as struct + :ref:`v4l2_queryctrl ` and struct + :c:type:`v4l2_control`. + + If the event is generated due to a call to + :ref:`VIDIOC_S_CTRL ` or + :ref:`VIDIOC_S_EXT_CTRLS `, then the + event will *not* be sent to the file handle that called the ioctl + function. This prevents nasty feedback loops. If you *do* want to + get the event, then set the ``V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK`` + flag. + + This event type will ensure that no information is lost when more + events are raised than there is room internally. In that case the + struct :c:type:`v4l2_event_ctrl` of the + second-oldest event is kept, but the ``changes`` field of the + second-oldest event is ORed with the ``changes`` field of the + oldest event. + * - ``V4L2_EVENT_FRAME_SYNC`` + - 4 + - Triggered immediately when the reception of a frame has begun. + This event has a struct + :c:type:`v4l2_event_frame_sync` + associated with it. + + If the hardware needs to be stopped in the case of a buffer + underrun it might not be able to generate this event. In such + cases the ``frame_sequence`` field in struct + :c:type:`v4l2_event_frame_sync` will not + be incremented. This causes two consecutive frame sequence numbers + to have n times frame interval in between them. + * - ``V4L2_EVENT_SOURCE_CHANGE`` + - 5 + - This event is triggered when a source parameter change is detected + during runtime by the video device. It can be a runtime resolution + change triggered by a video decoder or the format change happening + on an input connector. This event requires that the ``id`` matches + the input index (when used with a video device node) or the pad + index (when used with a subdevice node) from which you want to + receive events. + + This event has a struct + :c:type:`v4l2_event_src_change` + associated with it. The ``changes`` bitfield denotes what has + changed for the subscribed pad. If multiple events occurred before + application could dequeue them, then the changes will have the + ORed value of all the events generated. + * - ``V4L2_EVENT_MOTION_DET`` + - 6 + - Triggered whenever the motion detection state for one or more of + the regions changes. This event has a struct + :c:type:`v4l2_event_motion_det` + associated with it. + * - ``V4L2_EVENT_PRIVATE_START`` + - 0x08000000 + - Base event number for driver-private events. + + +.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.5cm}| + +.. c:type:: v4l2_event_vsync + +.. flat-table:: struct v4l2_event_vsync + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``field`` + - The upcoming field. See enum :c:type:`v4l2_field`. + + +.. tabularcolumns:: |p{3.5cm}|p{3.0cm}|p{10.8cm}| + +.. c:type:: v4l2_event_ctrl + +.. flat-table:: struct v4l2_event_ctrl + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u32 + - ``changes`` + - A bitmask that tells what has changed. See + :ref:`ctrl-changes-flags`. + * - __u32 + - ``type`` + - The type of the control. See enum + :c:type:`v4l2_ctrl_type`. + * - union { + - (anonymous) + * - __s32 + - ``value`` + - The 32-bit value of the control for 32-bit control types. This is + 0 for string controls since the value of a string cannot be passed + using :ref:`VIDIOC_DQEVENT`. + * - __s64 + - ``value64`` + - The 64-bit value of the control for 64-bit control types. + * - } + - + * - __u32 + - ``flags`` + - The control flags. See :ref:`control-flags`. + * - __s32 + - ``minimum`` + - The minimum value of the control. See struct + :ref:`v4l2_queryctrl `. + * - __s32 + - ``maximum`` + - The maximum value of the control. See struct + :ref:`v4l2_queryctrl `. + * - __s32 + - ``step`` + - The step value of the control. See struct + :ref:`v4l2_queryctrl `. + * - __s32 + - ``default_value`` + - The default value of the control. See struct + :ref:`v4l2_queryctrl `. + + +.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.5cm}| + +.. c:type:: v4l2_event_frame_sync + +.. flat-table:: struct v4l2_event_frame_sync + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u32 + - ``frame_sequence`` + - The sequence number of the frame being received. + + +.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.5cm}| + +.. c:type:: v4l2_event_src_change + +.. flat-table:: struct v4l2_event_src_change + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u32 + - ``changes`` + - A bitmask that tells what has changed. See + :ref:`src-changes-flags`. + + +.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.5cm}| + +.. c:type:: v4l2_event_motion_det + +.. flat-table:: struct v4l2_event_motion_det + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u32 + - ``flags`` + - Currently only one flag is available: if + ``V4L2_EVENT_MD_FL_HAVE_FRAME_SEQ`` is set, then the + ``frame_sequence`` field is valid, otherwise that field should be + ignored. + * - __u32 + - ``frame_sequence`` + - The sequence number of the frame being received. Only valid if the + ``V4L2_EVENT_MD_FL_HAVE_FRAME_SEQ`` flag was set. + * - __u32 + - ``region_mask`` + - The bitmask of the regions that reported motion. There is at least + one region. If this field is 0, then no motion was detected at + all. If there is no ``V4L2_CID_DETECT_MD_REGION_GRID`` control + (see :ref:`detect-controls`) to assign a different region to + each cell in the motion detection grid, then that all cells are + automatically assigned to the default region 0. + + +.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.5cm}| + +.. _ctrl-changes-flags: + +.. flat-table:: Control Changes + :header-rows: 0 + :stub-columns: 0 + :widths: 3 1 4 + + * - ``V4L2_EVENT_CTRL_CH_VALUE`` + - 0x0001 + - This control event was triggered because the value of the control + changed. Special cases: Volatile controls do no generate this + event; If a control has the ``V4L2_CTRL_FLAG_EXECUTE_ON_WRITE`` + flag set, then this event is sent as well, regardless its value. + * - ``V4L2_EVENT_CTRL_CH_FLAGS`` + - 0x0002 + - This control event was triggered because the control flags + changed. + * - ``V4L2_EVENT_CTRL_CH_RANGE`` + - 0x0004 + - This control event was triggered because the minimum, maximum, + step or the default value of the control changed. + * - ``V4L2_EVENT_CTRL_CH_DIMENSIONS`` + - 0x0008 + - This control event was triggered because the dimensions of the + control changed. Note that the number of dimensions remains the + same. + + +.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.5cm}| + +.. _src-changes-flags: + +.. flat-table:: Source Changes + :header-rows: 0 + :stub-columns: 0 + :widths: 3 1 4 + + * - ``V4L2_EVENT_SRC_CH_RESOLUTION`` + - 0x0001 + - This event gets triggered when a resolution change is detected at + an input. This can come from an input connector or from a video + decoder. Applications will have to query the new resolution (if + any, the signal may also have been lost). + + For stateful decoders follow the guidelines in :ref:`decoder`. + Video Capture devices have to query the new timings using + :ref:`VIDIOC_QUERY_DV_TIMINGS` or + :ref:`VIDIOC_QUERYSTD `. + + *Important*: even if the new video timings appear identical to the old + ones, receiving this event indicates that there was an issue with the + video signal and you must stop and restart streaming + (:ref:`VIDIOC_STREAMOFF ` + followed by :ref:`VIDIOC_STREAMON `). The reason is + that many Video Capture devices are not able to recover from a temporary + loss of signal and so restarting streaming I/O is required in order for + the hardware to synchronize to the video signal. + +Return Value +============ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes ` chapter. -- cgit v1.2.3