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, 419 insertions, 0 deletions

diff --git a/drivers/base/auxiliary.c b/drivers/base/auxiliary.c
new file mode 100644
index 000000000..8c5e65930
--- /dev/null
+++ b/drivers/base/auxiliary.c
@@ -0,0 +1,419 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2019-2020 Intel Corporation
+ *
+ * Please see Documentation/driver-api/auxiliary_bus.rst for more information.
+ */
+
+#define pr_fmt(fmt) "%s:%s: " fmt, KBUILD_MODNAME, __func__
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+#include <linux/string.h>
+#include <linux/auxiliary_bus.h>
+#include "base.h"
+
+/**
+ * DOC: PURPOSE
+ *
+ * In some subsystems, the functionality of the core device (PCI/ACPI/other) is
+ * too complex for a single device to be managed by a monolithic driver (e.g.
+ * Sound Open Firmware), multiple devices might implement a common intersection
+ * of functionality (e.g. NICs + RDMA), or a driver may want to export an
+ * interface for another subsystem to drive (e.g. SIOV Physical Function export
+ * Virtual Function management).  A split of the functionality into child-
+ * devices representing sub-domains of functionality makes it possible to
+ * compartmentalize, layer, and distribute domain-specific concerns via a Linux
+ * device-driver model.
+ *
+ * An example for this kind of requirement is the audio subsystem where a
+ * single IP is handling multiple entities such as HDMI, Soundwire, local
+ * devices such as mics/speakers etc. The split for the core's functionality
+ * can be arbitrary or be defined by the DSP firmware topology and include
+ * hooks for test/debug. This allows for the audio core device to be minimal
+ * and focused on hardware-specific control and communication.
+ *
+ * Each auxiliary_device represents a part of its parent functionality. The
+ * generic behavior can be extended and specialized as needed by encapsulating
+ * an auxiliary_device within other domain-specific structures and the use of
+ * .ops callbacks. Devices on the auxiliary bus do not share any structures and
+ * the use of a communication channel with the parent is domain-specific.
+ *
+ * Note that ops are intended as a way to augment instance behavior within a
+ * class of auxiliary devices, it is not the mechanism for exporting common
+ * infrastructure from the parent. Consider EXPORT_SYMBOL_NS() to convey
+ * infrastructure from the parent module to the auxiliary module(s).
+ */
+
+/**
+ * DOC: USAGE
+ *
+ * The auxiliary bus is to be used when a driver and one or more kernel
+ * modules, who share a common header file with the driver, need a mechanism to
+ * connect and provide access to a shared object allocated by the
+ * auxiliary_device's registering driver.  The registering driver for the
+ * auxiliary_device(s) and the kernel module(s) registering auxiliary_drivers
+ * can be from the same subsystem, or from multiple subsystems.
+ *
+ * The emphasis here is on a common generic interface that keeps subsystem
+ * customization out of the bus infrastructure.
+ *
+ * One example is a PCI network device that is RDMA-capable and exports a child
+ * device to be driven by an auxiliary_driver in the RDMA subsystem.  The PCI
+ * driver allocates and registers an auxiliary_device for each physical
+ * function on the NIC.  The RDMA driver registers an auxiliary_driver that
+ * claims each of these auxiliary_devices.  This conveys data/ops published by
+ * the parent PCI device/driver to the RDMA auxiliary_driver.
+ *
+ * Another use case is for the PCI device to be split out into multiple sub
+ * functions.  For each sub function an auxiliary_device is created.  A PCI sub
+ * function driver binds to such devices that creates its own one or more class
+ * devices.  A PCI sub function auxiliary device is likely to be contained in a
+ * struct with additional attributes such as user defined sub function number
+ * and optional attributes such as resources and a link to the parent device.
+ * These attributes could be used by systemd/udev; and hence should be
+ * initialized before a driver binds to an auxiliary_device.
+ *
+ * A key requirement for utilizing the auxiliary bus is that there is no
+ * dependency on a physical bus, device, register accesses or regmap support.
+ * These individual devices split from the core cannot live on the platform bus
+ * as they are not physical devices that are controlled by DT/ACPI.  The same
+ * argument applies for not using MFD in this scenario as MFD relies on
+ * individual function devices being physical devices.
+ */
+
+/**
+ * DOC: EXAMPLE
+ *
+ * Auxiliary devices are created and registered by a subsystem-level core
+ * device that needs to break up its functionality into smaller fragments. One
+ * way to extend the scope of an auxiliary_device is to encapsulate it within a
+ * domain- pecific structure defined by the parent device. This structure
+ * contains the auxiliary_device and any associated shared data/callbacks
+ * needed to establish the connection with the parent.
+ *
+ * An example is:
+ *
+ * .. code-block:: c
+ *
+ *         struct foo {
+ *		struct auxiliary_device auxdev;
+ *		void (*connect)(struct auxiliary_device *auxdev);
+ *		void (*disconnect)(struct auxiliary_device *auxdev);
+ *		void *data;
+ *        };
+ *
+ * The parent device then registers the auxiliary_device by calling
+ * auxiliary_device_init(), and then auxiliary_device_add(), with the pointer
+ * to the auxdev member of the above structure. The parent provides a name for
+ * the auxiliary_device that, combined with the parent's KBUILD_MODNAME,
+ * creates a match_name that is be used for matching and binding with a driver.
+ *
+ * Whenever an auxiliary_driver is registered, based on the match_name, the
+ * auxiliary_driver's probe() is invoked for the matching devices.  The
+ * auxiliary_driver can also be encapsulated inside custom drivers that make
+ * the core device's functionality extensible by adding additional
+ * domain-specific ops as follows:
+ *
+ * .. code-block:: c
+ *
+ *	struct my_ops {
+ *		void (*send)(struct auxiliary_device *auxdev);
+ *		void (*receive)(struct auxiliary_device *auxdev);
+ *	};
+ *
+ *
+ *	struct my_driver {
+ *		struct auxiliary_driver auxiliary_drv;
+ *		const struct my_ops ops;
+ *	};
+ *
+ * An example of this type of usage is:
+ *
+ * .. code-block:: c
+ *
+ *	const struct auxiliary_device_id my_auxiliary_id_table[] = {
+ *		{ .name = "foo_mod.foo_dev" },
+ *		{ },
+ *	};
+ *
+ *	const struct my_ops my_custom_ops = {
+ *		.send = my_tx,
+ *		.receive = my_rx,
+ *	};
+ *
+ *	const struct my_driver my_drv = {
+ *		.auxiliary_drv = {
+ *			.name = "myauxiliarydrv",
+ *			.id_table = my_auxiliary_id_table,
+ *			.probe = my_probe,
+ *			.remove = my_remove,
+ *			.shutdown = my_shutdown,
+ *		},
+ *		.ops = my_custom_ops,
+ *	};
+ */
+
+static const struct auxiliary_device_id *auxiliary_match_id(const struct auxiliary_device_id *id,
+							    const struct auxiliary_device *auxdev)
+{
+	for (; id->name[0]; id++) {
+		const char *p = strrchr(dev_name(&auxdev->dev), '.');
+		int match_size;
+
+		if (!p)
+			continue;
+		match_size = p - dev_name(&auxdev->dev);
+
+		/* use dev_name(&auxdev->dev) prefix before last '.' char to match to */
+		if (strlen(id->name) == match_size &&
+		    !strncmp(dev_name(&auxdev->dev), id->name, match_size))
+			return id;
+	}
+	return NULL;
+}
+
+static int auxiliary_match(struct device *dev, struct device_driver *drv)
+{
+	struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
+	struct auxiliary_driver *auxdrv = to_auxiliary_drv(drv);
+
+	return !!auxiliary_match_id(auxdrv->id_table, auxdev);
+}
+
+static int auxiliary_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	const char *name, *p;
+
+	name = dev_name(dev);
+	p = strrchr(name, '.');
+
+	return add_uevent_var(env, "MODALIAS=%s%.*s", AUXILIARY_MODULE_PREFIX,
+			      (int)(p - name), name);
+}
+
+static const struct dev_pm_ops auxiliary_dev_pm_ops = {
+	SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend, pm_generic_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(pm_generic_suspend, pm_generic_resume)
+};
+
+static int auxiliary_bus_probe(struct device *dev)
+{
+	struct auxiliary_driver *auxdrv = to_auxiliary_drv(dev->driver);
+	struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
+	int ret;
+
+	ret = dev_pm_domain_attach(dev, true);
+	if (ret) {
+		dev_warn(dev, "Failed to attach to PM Domain : %d\n", ret);
+		return ret;
+	}
+
+	ret = auxdrv->probe(auxdev, auxiliary_match_id(auxdrv->id_table, auxdev));
+	if (ret)
+		dev_pm_domain_detach(dev, true);
+
+	return ret;
+}
+
+static void auxiliary_bus_remove(struct device *dev)
+{
+	struct auxiliary_driver *auxdrv = to_auxiliary_drv(dev->driver);
+	struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
+
+	if (auxdrv->remove)
+		auxdrv->remove(auxdev);
+	dev_pm_domain_detach(dev, true);
+}
+
+static void auxiliary_bus_shutdown(struct device *dev)
+{
+	struct auxiliary_driver *auxdrv = NULL;
+	struct auxiliary_device *auxdev;
+
+	if (dev->driver) {
+		auxdrv = to_auxiliary_drv(dev->driver);
+		auxdev = to_auxiliary_dev(dev);
+	}
+
+	if (auxdrv && auxdrv->shutdown)
+		auxdrv->shutdown(auxdev);
+}
+
+static struct bus_type auxiliary_bus_type = {
+	.name = "auxiliary",
+	.probe = auxiliary_bus_probe,
+	.remove = auxiliary_bus_remove,
+	.shutdown = auxiliary_bus_shutdown,
+	.match = auxiliary_match,
+	.uevent = auxiliary_uevent,
+	.pm = &auxiliary_dev_pm_ops,
+};
+
+/**
+ * auxiliary_device_init - check auxiliary_device and initialize
+ * @auxdev: auxiliary device struct
+ *
+ * This is the second step in the three-step process to register an
+ * auxiliary_device.
+ *
+ * When this function returns an error code, then the device_initialize will
+ * *not* have been performed, and the caller will be responsible to free any
+ * memory allocated for the auxiliary_device in the error path directly.
+ *
+ * It returns 0 on success.  On success, the device_initialize has been
+ * performed.  After this point any error unwinding will need to include a call
+ * to auxiliary_device_uninit().  In this post-initialize error scenario, a call
+ * to the device's .release callback will be triggered, and all memory clean-up
+ * is expected to be handled there.
+ */
+int auxiliary_device_init(struct auxiliary_device *auxdev)
+{
+	struct device *dev = &auxdev->dev;
+
+	if (!dev->parent) {
+		pr_err("auxiliary_device has a NULL dev->parent\n");
+		return -EINVAL;
+	}
+
+	if (!auxdev->name) {
+		pr_err("auxiliary_device has a NULL name\n");
+		return -EINVAL;
+	}
+
+	dev->bus = &auxiliary_bus_type;
+	device_initialize(&auxdev->dev);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(auxiliary_device_init);
+
+/**
+ * __auxiliary_device_add - add an auxiliary bus device
+ * @auxdev: auxiliary bus device to add to the bus
+ * @modname: name of the parent device's driver module
+ *
+ * This is the third step in the three-step process to register an
+ * auxiliary_device.
+ *
+ * This function must be called after a successful call to
+ * auxiliary_device_init(), which will perform the device_initialize.  This
+ * means that if this returns an error code, then a call to
+ * auxiliary_device_uninit() must be performed so that the .release callback
+ * will be triggered to free the memory associated with the auxiliary_device.
+ *
+ * The expectation is that users will call the "auxiliary_device_add" macro so
+ * that the caller's KBUILD_MODNAME is automatically inserted for the modname
+ * parameter.  Only if a user requires a custom name would this version be
+ * called directly.
+ */
+int __auxiliary_device_add(struct auxiliary_device *auxdev, const char *modname)
+{
+	struct device *dev = &auxdev->dev;
+	int ret;
+
+	if (!modname) {
+		dev_err(dev, "auxiliary device modname is NULL\n");
+		return -EINVAL;
+	}
+
+	ret = dev_set_name(dev, "%s.%s.%d", modname, auxdev->name, auxdev->id);
+	if (ret) {
+		dev_err(dev, "auxiliary device dev_set_name failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = device_add(dev);
+	if (ret)
+		dev_err(dev, "adding auxiliary device failed!: %d\n", ret);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(__auxiliary_device_add);
+
+/**
+ * auxiliary_find_device - auxiliary device iterator for locating a particular device.
+ * @start: Device to begin with
+ * @data: Data to pass to match function
+ * @match: Callback function to check device
+ *
+ * This function returns a reference to a device that is 'found'
+ * for later use, as determined by the @match callback.
+ *
+ * The reference returned should be released with put_device().
+ *
+ * The callback should return 0 if the device doesn't match and non-zero
+ * if it does.  If the callback returns non-zero, this function will
+ * return to the caller and not iterate over any more devices.
+ */
+struct auxiliary_device *auxiliary_find_device(struct device *start,
+					       const void *data,
+					       int (*match)(struct device *dev, const void *data))
+{
+	struct device *dev;
+
+	dev = bus_find_device(&auxiliary_bus_type, start, data, match);
+	if (!dev)
+		return NULL;
+
+	return to_auxiliary_dev(dev);
+}
+EXPORT_SYMBOL_GPL(auxiliary_find_device);
+
+/**
+ * __auxiliary_driver_register - register a driver for auxiliary bus devices
+ * @auxdrv: auxiliary_driver structure
+ * @owner: owning module/driver
+ * @modname: KBUILD_MODNAME for parent driver
+ *
+ * The expectation is that users will call the "auxiliary_driver_register"
+ * macro so that the caller's KBUILD_MODNAME is automatically inserted for the
+ * modname parameter.  Only if a user requires a custom name would this version
+ * be called directly.
+ */
+int __auxiliary_driver_register(struct auxiliary_driver *auxdrv,
+				struct module *owner, const char *modname)
+{
+	int ret;
+
+	if (WARN_ON(!auxdrv->probe) || WARN_ON(!auxdrv->id_table))
+		return -EINVAL;
+
+	if (auxdrv->name)
+		auxdrv->driver.name = kasprintf(GFP_KERNEL, "%s.%s", modname,
+						auxdrv->name);
+	else
+		auxdrv->driver.name = kasprintf(GFP_KERNEL, "%s", modname);
+	if (!auxdrv->driver.name)
+		return -ENOMEM;
+
+	auxdrv->driver.owner = owner;
+	auxdrv->driver.bus = &auxiliary_bus_type;
+	auxdrv->driver.mod_name = modname;
+
+	ret = driver_register(&auxdrv->driver);
+	if (ret)
+		kfree(auxdrv->driver.name);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(__auxiliary_driver_register);
+
+/**
+ * auxiliary_driver_unregister - unregister a driver
+ * @auxdrv: auxiliary_driver structure
+ */
+void auxiliary_driver_unregister(struct auxiliary_driver *auxdrv)
+{
+	driver_unregister(&auxdrv->driver);
+	kfree(auxdrv->driver.name);
+}
+EXPORT_SYMBOL_GPL(auxiliary_driver_unregister);
+
+void __init auxiliary_bus_init(void)
+{
+	WARN_ON(bus_register(&auxiliary_bus_type));
+}