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().
  ...

1 files changed, 517 insertions, 0 deletions

diff --git a/drivers/media/platform/video-mux.c b/drivers/media/platform/video-mux.c
new file mode 100644
index 000000000..71d97042a
--- /dev/null
+++ b/drivers/media/platform/video-mux.c
@@ -0,0 +1,517 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * video stream multiplexer controlled via mux control
+ *
+ * Copyright (C) 2013 Pengutronix, Sascha Hauer <kernel@pengutronix.de>
+ * Copyright (C) 2016-2017 Pengutronix, Philipp Zabel <kernel@pengutronix.de>
+ */
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/mux/consumer.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-mc.h>
+#include <media/v4l2-subdev.h>
+
+struct video_mux {
+	struct v4l2_subdev subdev;
+	struct v4l2_async_notifier notifier;
+	struct media_pad *pads;
+	struct v4l2_mbus_framefmt *format_mbus;
+	struct mux_control *mux;
+	struct mutex lock;
+	int active;
+};
+
+static const struct v4l2_mbus_framefmt video_mux_format_mbus_default = {
+	.width = 1,
+	.height = 1,
+	.code = MEDIA_BUS_FMT_Y8_1X8,
+	.field = V4L2_FIELD_NONE,
+};
+
+static inline struct video_mux *
+notifier_to_video_mux(struct v4l2_async_notifier *n)
+{
+	return container_of(n, struct video_mux, notifier);
+}
+
+static inline struct video_mux *v4l2_subdev_to_video_mux(struct v4l2_subdev *sd)
+{
+	return container_of(sd, struct video_mux, subdev);
+}
+
+static int video_mux_link_setup(struct media_entity *entity,
+				const struct media_pad *local,
+				const struct media_pad *remote, u32 flags)
+{
+	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
+	u16 source_pad = entity->num_pads - 1;
+	int ret = 0;
+
+	/*
+	 * The mux state is determined by the enabled sink pad link.
+	 * Enabling or disabling the source pad link has no effect.
+	 */
+	if (local->flags & MEDIA_PAD_FL_SOURCE)
+		return 0;
+
+	dev_dbg(sd->dev, "link setup '%s':%d->'%s':%d[%d]",
+		remote->entity->name, remote->index, local->entity->name,
+		local->index, flags & MEDIA_LNK_FL_ENABLED);
+
+	mutex_lock(&vmux->lock);
+
+	if (flags & MEDIA_LNK_FL_ENABLED) {
+		if (vmux->active == local->index)
+			goto out;
+
+		if (vmux->active >= 0) {
+			ret = -EBUSY;
+			goto out;
+		}
+
+		dev_dbg(sd->dev, "setting %d active\n", local->index);
+		ret = mux_control_try_select(vmux->mux, local->index);
+		if (ret < 0)
+			goto out;
+		vmux->active = local->index;
+
+		/* Propagate the active format to the source */
+		vmux->format_mbus[source_pad] = vmux->format_mbus[vmux->active];
+	} else {
+		if (vmux->active != local->index)
+			goto out;
+
+		dev_dbg(sd->dev, "going inactive\n");
+		mux_control_deselect(vmux->mux);
+		vmux->active = -1;
+	}
+
+out:
+	mutex_unlock(&vmux->lock);
+	return ret;
+}
+
+static const struct media_entity_operations video_mux_ops = {
+	.link_setup = video_mux_link_setup,
+	.link_validate = v4l2_subdev_link_validate,
+	.get_fwnode_pad = v4l2_subdev_get_fwnode_pad_1_to_1,
+};
+
+static int video_mux_s_stream(struct v4l2_subdev *sd, int enable)
+{
+	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
+	struct v4l2_subdev *upstream_sd;
+	struct media_pad *pad;
+
+	if (vmux->active == -1) {
+		dev_err(sd->dev, "Can not start streaming on inactive mux\n");
+		return -EINVAL;
+	}
+
+	pad = media_pad_remote_pad_first(&sd->entity.pads[vmux->active]);
+	if (!pad) {
+		dev_err(sd->dev, "Failed to find remote source pad\n");
+		return -ENOLINK;
+	}
+
+	if (!is_media_entity_v4l2_subdev(pad->entity)) {
+		dev_err(sd->dev, "Upstream entity is not a v4l2 subdev\n");
+		return -ENODEV;
+	}
+
+	upstream_sd = media_entity_to_v4l2_subdev(pad->entity);
+
+	return v4l2_subdev_call(upstream_sd, video, s_stream, enable);
+}
+
+static const struct v4l2_subdev_video_ops video_mux_subdev_video_ops = {
+	.s_stream = video_mux_s_stream,
+};
+
+static struct v4l2_mbus_framefmt *
+__video_mux_get_pad_format(struct v4l2_subdev *sd,
+			   struct v4l2_subdev_state *sd_state,
+			   unsigned int pad, u32 which)
+{
+	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
+
+	switch (which) {
+	case V4L2_SUBDEV_FORMAT_TRY:
+		return v4l2_subdev_get_try_format(sd, sd_state, pad);
+	case V4L2_SUBDEV_FORMAT_ACTIVE:
+		return &vmux->format_mbus[pad];
+	default:
+		return NULL;
+	}
+}
+
+static int video_mux_get_format(struct v4l2_subdev *sd,
+			    struct v4l2_subdev_state *sd_state,
+			    struct v4l2_subdev_format *sdformat)
+{
+	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
+
+	mutex_lock(&vmux->lock);
+
+	sdformat->format = *__video_mux_get_pad_format(sd, sd_state,
+						       sdformat->pad,
+						       sdformat->which);
+
+	mutex_unlock(&vmux->lock);
+
+	return 0;
+}
+
+static int video_mux_set_format(struct v4l2_subdev *sd,
+			    struct v4l2_subdev_state *sd_state,
+			    struct v4l2_subdev_format *sdformat)
+{
+	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
+	struct v4l2_mbus_framefmt *mbusformat, *source_mbusformat;
+	struct media_pad *pad = &vmux->pads[sdformat->pad];
+	u16 source_pad = sd->entity.num_pads - 1;
+
+	mbusformat = __video_mux_get_pad_format(sd, sd_state, sdformat->pad,
+						sdformat->which);
+	if (!mbusformat)
+		return -EINVAL;
+
+	source_mbusformat = __video_mux_get_pad_format(sd, sd_state,
+						       source_pad,
+						       sdformat->which);
+	if (!source_mbusformat)
+		return -EINVAL;
+
+	/* No size limitations except V4L2 compliance requirements */
+	v4l_bound_align_image(&sdformat->format.width, 1, 65536, 0,
+			      &sdformat->format.height, 1, 65536, 0, 0);
+
+	/* All formats except LVDS and vendor specific formats are acceptable */
+	switch (sdformat->format.code) {
+	case MEDIA_BUS_FMT_RGB444_1X12:
+	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_BE:
+	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE:
+	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_BE:
+	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_LE:
+	case MEDIA_BUS_FMT_RGB565_1X16:
+	case MEDIA_BUS_FMT_BGR565_2X8_BE:
+	case MEDIA_BUS_FMT_BGR565_2X8_LE:
+	case MEDIA_BUS_FMT_RGB565_2X8_BE:
+	case MEDIA_BUS_FMT_RGB565_2X8_LE:
+	case MEDIA_BUS_FMT_RGB666_1X18:
+	case MEDIA_BUS_FMT_RBG888_1X24:
+	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
+	case MEDIA_BUS_FMT_BGR888_1X24:
+	case MEDIA_BUS_FMT_GBR888_1X24:
+	case MEDIA_BUS_FMT_RGB888_1X24:
+	case MEDIA_BUS_FMT_RGB888_2X12_BE:
+	case MEDIA_BUS_FMT_RGB888_2X12_LE:
+	case MEDIA_BUS_FMT_ARGB8888_1X32:
+	case MEDIA_BUS_FMT_RGB888_1X32_PADHI:
+	case MEDIA_BUS_FMT_RGB101010_1X30:
+	case MEDIA_BUS_FMT_RGB121212_1X36:
+	case MEDIA_BUS_FMT_RGB161616_1X48:
+	case MEDIA_BUS_FMT_Y8_1X8:
+	case MEDIA_BUS_FMT_UV8_1X8:
+	case MEDIA_BUS_FMT_UYVY8_1_5X8:
+	case MEDIA_BUS_FMT_VYUY8_1_5X8:
+	case MEDIA_BUS_FMT_YUYV8_1_5X8:
+	case MEDIA_BUS_FMT_YVYU8_1_5X8:
+	case MEDIA_BUS_FMT_UYVY8_2X8:
+	case MEDIA_BUS_FMT_VYUY8_2X8:
+	case MEDIA_BUS_FMT_YUYV8_2X8:
+	case MEDIA_BUS_FMT_YVYU8_2X8:
+	case MEDIA_BUS_FMT_Y10_1X10:
+	case MEDIA_BUS_FMT_UYVY10_2X10:
+	case MEDIA_BUS_FMT_VYUY10_2X10:
+	case MEDIA_BUS_FMT_YUYV10_2X10:
+	case MEDIA_BUS_FMT_YVYU10_2X10:
+	case MEDIA_BUS_FMT_Y12_1X12:
+	case MEDIA_BUS_FMT_UYVY12_2X12:
+	case MEDIA_BUS_FMT_VYUY12_2X12:
+	case MEDIA_BUS_FMT_YUYV12_2X12:
+	case MEDIA_BUS_FMT_YVYU12_2X12:
+	case MEDIA_BUS_FMT_UYVY8_1X16:
+	case MEDIA_BUS_FMT_VYUY8_1X16:
+	case MEDIA_BUS_FMT_YUYV8_1X16:
+	case MEDIA_BUS_FMT_YVYU8_1X16:
+	case MEDIA_BUS_FMT_YDYUYDYV8_1X16:
+	case MEDIA_BUS_FMT_UYVY10_1X20:
+	case MEDIA_BUS_FMT_VYUY10_1X20:
+	case MEDIA_BUS_FMT_YUYV10_1X20:
+	case MEDIA_BUS_FMT_YVYU10_1X20:
+	case MEDIA_BUS_FMT_VUY8_1X24:
+	case MEDIA_BUS_FMT_YUV8_1X24:
+	case MEDIA_BUS_FMT_UYYVYY8_0_5X24:
+	case MEDIA_BUS_FMT_UYVY12_1X24:
+	case MEDIA_BUS_FMT_VYUY12_1X24:
+	case MEDIA_BUS_FMT_YUYV12_1X24:
+	case MEDIA_BUS_FMT_YVYU12_1X24:
+	case MEDIA_BUS_FMT_YUV10_1X30:
+	case MEDIA_BUS_FMT_UYYVYY10_0_5X30:
+	case MEDIA_BUS_FMT_AYUV8_1X32:
+	case MEDIA_BUS_FMT_UYYVYY12_0_5X36:
+	case MEDIA_BUS_FMT_YUV12_1X36:
+	case MEDIA_BUS_FMT_YUV16_1X48:
+	case MEDIA_BUS_FMT_UYYVYY16_0_5X48:
+	case MEDIA_BUS_FMT_JPEG_1X8:
+	case MEDIA_BUS_FMT_AHSV8888_1X32:
+	case MEDIA_BUS_FMT_SBGGR8_1X8:
+	case MEDIA_BUS_FMT_SGBRG8_1X8:
+	case MEDIA_BUS_FMT_SGRBG8_1X8:
+	case MEDIA_BUS_FMT_SRGGB8_1X8:
+	case MEDIA_BUS_FMT_SBGGR10_1X10:
+	case MEDIA_BUS_FMT_SGBRG10_1X10:
+	case MEDIA_BUS_FMT_SGRBG10_1X10:
+	case MEDIA_BUS_FMT_SRGGB10_1X10:
+	case MEDIA_BUS_FMT_SBGGR12_1X12:
+	case MEDIA_BUS_FMT_SGBRG12_1X12:
+	case MEDIA_BUS_FMT_SGRBG12_1X12:
+	case MEDIA_BUS_FMT_SRGGB12_1X12:
+	case MEDIA_BUS_FMT_SBGGR14_1X14:
+	case MEDIA_BUS_FMT_SGBRG14_1X14:
+	case MEDIA_BUS_FMT_SGRBG14_1X14:
+	case MEDIA_BUS_FMT_SRGGB14_1X14:
+	case MEDIA_BUS_FMT_SBGGR16_1X16:
+	case MEDIA_BUS_FMT_SGBRG16_1X16:
+	case MEDIA_BUS_FMT_SGRBG16_1X16:
+	case MEDIA_BUS_FMT_SRGGB16_1X16:
+		break;
+	default:
+		sdformat->format.code = MEDIA_BUS_FMT_Y8_1X8;
+		break;
+	}
+	if (sdformat->format.field == V4L2_FIELD_ANY)
+		sdformat->format.field = V4L2_FIELD_NONE;
+
+	mutex_lock(&vmux->lock);
+
+	/* Source pad mirrors active sink pad, no limitations on sink pads */
+	if ((pad->flags & MEDIA_PAD_FL_SOURCE) && vmux->active >= 0)
+		sdformat->format = vmux->format_mbus[vmux->active];
+
+	*mbusformat = sdformat->format;
+
+	/* Propagate the format from an active sink to source */
+	if ((pad->flags & MEDIA_PAD_FL_SINK) && (pad->index == vmux->active))
+		*source_mbusformat = sdformat->format;
+
+	mutex_unlock(&vmux->lock);
+
+	return 0;
+}
+
+static int video_mux_init_cfg(struct v4l2_subdev *sd,
+			      struct v4l2_subdev_state *sd_state)
+{
+	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
+	struct v4l2_mbus_framefmt *mbusformat;
+	unsigned int i;
+
+	mutex_lock(&vmux->lock);
+
+	for (i = 0; i < sd->entity.num_pads; i++) {
+		mbusformat = v4l2_subdev_get_try_format(sd, sd_state, i);
+		*mbusformat = video_mux_format_mbus_default;
+	}
+
+	mutex_unlock(&vmux->lock);
+
+	return 0;
+}
+
+static const struct v4l2_subdev_pad_ops video_mux_pad_ops = {
+	.init_cfg = video_mux_init_cfg,
+	.get_fmt = video_mux_get_format,
+	.set_fmt = video_mux_set_format,
+};
+
+static const struct v4l2_subdev_ops video_mux_subdev_ops = {
+	.pad = &video_mux_pad_ops,
+	.video = &video_mux_subdev_video_ops,
+};
+
+static int video_mux_notify_bound(struct v4l2_async_notifier *notifier,
+				  struct v4l2_subdev *sd,
+				  struct v4l2_async_subdev *asd)
+{
+	struct video_mux *vmux = notifier_to_video_mux(notifier);
+
+	return v4l2_create_fwnode_links(sd, &vmux->subdev);
+}
+
+static const struct v4l2_async_notifier_operations video_mux_notify_ops = {
+	.bound = video_mux_notify_bound,
+};
+
+static int video_mux_async_register(struct video_mux *vmux,
+				    unsigned int num_input_pads)
+{
+	unsigned int i;
+	int ret;
+
+	v4l2_async_nf_init(&vmux->notifier);
+
+	for (i = 0; i < num_input_pads; i++) {
+		struct v4l2_async_subdev *asd;
+		struct fwnode_handle *ep, *remote_ep;
+
+		ep = fwnode_graph_get_endpoint_by_id(
+			dev_fwnode(vmux->subdev.dev), i, 0,
+			FWNODE_GRAPH_ENDPOINT_NEXT);
+		if (!ep)
+			continue;
+
+		/* Skip dangling endpoints for backwards compatibility */
+		remote_ep = fwnode_graph_get_remote_endpoint(ep);
+		if (!remote_ep) {
+			fwnode_handle_put(ep);
+			continue;
+		}
+		fwnode_handle_put(remote_ep);
+
+		asd = v4l2_async_nf_add_fwnode_remote(&vmux->notifier, ep,
+						      struct v4l2_async_subdev);
+
+		fwnode_handle_put(ep);
+
+		if (IS_ERR(asd)) {
+			ret = PTR_ERR(asd);
+			/* OK if asd already exists */
+			if (ret != -EEXIST)
+				return ret;
+		}
+	}
+
+	vmux->notifier.ops = &video_mux_notify_ops;
+
+	ret = v4l2_async_subdev_nf_register(&vmux->subdev, &vmux->notifier);
+	if (ret)
+		return ret;
+
+	return v4l2_async_register_subdev(&vmux->subdev);
+}
+
+static int video_mux_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	struct device_node *ep;
+	struct video_mux *vmux;
+	unsigned int num_pads = 0;
+	unsigned int i;
+	int ret;
+
+	vmux = devm_kzalloc(dev, sizeof(*vmux), GFP_KERNEL);
+	if (!vmux)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, vmux);
+
+	v4l2_subdev_init(&vmux->subdev, &video_mux_subdev_ops);
+	snprintf(vmux->subdev.name, sizeof(vmux->subdev.name), "%pOFn", np);
+	vmux->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+	vmux->subdev.dev = dev;
+
+	/*
+	 * The largest numbered port is the output port. It determines
+	 * total number of pads.
+	 */
+	for_each_endpoint_of_node(np, ep) {
+		struct of_endpoint endpoint;
+
+		of_graph_parse_endpoint(ep, &endpoint);
+		num_pads = max(num_pads, endpoint.port + 1);
+	}
+
+	if (num_pads < 2) {
+		dev_err(dev, "Not enough ports %d\n", num_pads);
+		return -EINVAL;
+	}
+
+	vmux->mux = devm_mux_control_get(dev, NULL);
+	if (IS_ERR(vmux->mux)) {
+		ret = PTR_ERR(vmux->mux);
+		return dev_err_probe(dev, ret, "Failed to get mux\n");
+	}
+
+	mutex_init(&vmux->lock);
+	vmux->active = -1;
+	vmux->pads = devm_kcalloc(dev, num_pads, sizeof(*vmux->pads),
+				  GFP_KERNEL);
+	if (!vmux->pads)
+		return -ENOMEM;
+
+	vmux->format_mbus = devm_kcalloc(dev, num_pads,
+					 sizeof(*vmux->format_mbus),
+					 GFP_KERNEL);
+	if (!vmux->format_mbus)
+		return -ENOMEM;
+
+	for (i = 0; i < num_pads; i++) {
+		vmux->pads[i].flags = (i < num_pads - 1) ? MEDIA_PAD_FL_SINK
+							 : MEDIA_PAD_FL_SOURCE;
+		vmux->format_mbus[i] = video_mux_format_mbus_default;
+	}
+
+	vmux->subdev.entity.function = MEDIA_ENT_F_VID_MUX;
+	ret = media_entity_pads_init(&vmux->subdev.entity, num_pads,
+				     vmux->pads);
+	if (ret < 0)
+		return ret;
+
+	vmux->subdev.entity.ops = &video_mux_ops;
+
+	ret = video_mux_async_register(vmux, num_pads - 1);
+	if (ret) {
+		v4l2_async_nf_unregister(&vmux->notifier);
+		v4l2_async_nf_cleanup(&vmux->notifier);
+	}
+
+	return ret;
+}
+
+static int video_mux_remove(struct platform_device *pdev)
+{
+	struct video_mux *vmux = platform_get_drvdata(pdev);
+	struct v4l2_subdev *sd = &vmux->subdev;
+
+	v4l2_async_nf_unregister(&vmux->notifier);
+	v4l2_async_nf_cleanup(&vmux->notifier);
+	v4l2_async_unregister_subdev(sd);
+	media_entity_cleanup(&sd->entity);
+
+	return 0;
+}
+
+static const struct of_device_id video_mux_dt_ids[] = {
+	{ .compatible = "video-mux", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, video_mux_dt_ids);
+
+static struct platform_driver video_mux_driver = {
+	.probe		= video_mux_probe,
+	.remove		= video_mux_remove,
+	.driver		= {
+		.of_match_table = video_mux_dt_ids,
+		.name = "video-mux",
+	},
+};
+
+module_platform_driver(video_mux_driver);
+
+MODULE_DESCRIPTION("video stream multiplexer");
+MODULE_AUTHOR("Sascha Hauer, Pengutronix");
+MODULE_AUTHOR("Philipp Zabel, Pengutronix");
+MODULE_LICENSE("GPL");