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, 438 insertions, 0 deletions

diff --git a/sound/firewire/motu/motu-stream.c b/sound/firewire/motu/motu-stream.c
new file mode 100644
index 000000000..64aec9c3e
--- /dev/null
+++ b/sound/firewire/motu/motu-stream.c
@@ -0,0 +1,438 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * motu-stream.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+#include "motu.h"
+
+#define	READY_TIMEOUT_MS	200
+
+#define ISOC_COMM_CONTROL_OFFSET		0x0b00
+#define  ISOC_COMM_CONTROL_MASK			0xffff0000
+#define  CHANGE_RX_ISOC_COMM_STATE		0x80000000
+#define  RX_ISOC_COMM_IS_ACTIVATED		0x40000000
+#define  RX_ISOC_COMM_CHANNEL_MASK		0x3f000000
+#define  RX_ISOC_COMM_CHANNEL_SHIFT		24
+#define  CHANGE_TX_ISOC_COMM_STATE		0x00800000
+#define  TX_ISOC_COMM_IS_ACTIVATED		0x00400000
+#define  TX_ISOC_COMM_CHANNEL_MASK		0x003f0000
+#define  TX_ISOC_COMM_CHANNEL_SHIFT		16
+
+#define PACKET_FORMAT_OFFSET			0x0b10
+#define  TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS	0x00000080
+#define  RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS	0x00000040
+#define  TX_PACKET_TRANSMISSION_SPEED_MASK	0x0000000f
+
+static int keep_resources(struct snd_motu *motu, unsigned int rate,
+			  struct amdtp_stream *stream)
+{
+	struct fw_iso_resources *resources;
+	struct snd_motu_packet_format *packet_format;
+	unsigned int midi_ports = 0;
+	int err;
+
+	if (stream == &motu->rx_stream) {
+		resources = &motu->rx_resources;
+		packet_format = &motu->rx_packet_formats;
+
+		if ((motu->spec->flags & SND_MOTU_SPEC_RX_MIDI_2ND_Q) ||
+		    (motu->spec->flags & SND_MOTU_SPEC_RX_MIDI_3RD_Q))
+			midi_ports = 1;
+	} else {
+		resources = &motu->tx_resources;
+		packet_format = &motu->tx_packet_formats;
+
+		if ((motu->spec->flags & SND_MOTU_SPEC_TX_MIDI_2ND_Q) ||
+		    (motu->spec->flags & SND_MOTU_SPEC_TX_MIDI_3RD_Q))
+			midi_ports = 1;
+	}
+
+	err = amdtp_motu_set_parameters(stream, rate, midi_ports,
+					packet_format);
+	if (err < 0)
+		return err;
+
+	return fw_iso_resources_allocate(resources,
+				amdtp_stream_get_max_payload(stream),
+				fw_parent_device(motu->unit)->max_speed);
+}
+
+static int begin_session(struct snd_motu *motu)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	// Configure the unit to start isochronous communication.
+	err = snd_motu_transaction_read(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg) & ~ISOC_COMM_CONTROL_MASK;
+
+	data |= CHANGE_RX_ISOC_COMM_STATE | RX_ISOC_COMM_IS_ACTIVATED |
+		(motu->rx_resources.channel << RX_ISOC_COMM_CHANNEL_SHIFT) |
+		CHANGE_TX_ISOC_COMM_STATE | TX_ISOC_COMM_IS_ACTIVATED |
+		(motu->tx_resources.channel << TX_ISOC_COMM_CHANNEL_SHIFT);
+
+	reg = cpu_to_be32(data);
+	return snd_motu_transaction_write(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
+					  sizeof(reg));
+}
+
+static void finish_session(struct snd_motu *motu)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_protocol_switch_fetching_mode(motu, false);
+	if (err < 0)
+		return;
+
+	err = snd_motu_transaction_read(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return;
+	data = be32_to_cpu(reg);
+
+	data &= ~(RX_ISOC_COMM_IS_ACTIVATED | TX_ISOC_COMM_IS_ACTIVATED);
+	data |= CHANGE_RX_ISOC_COMM_STATE | CHANGE_TX_ISOC_COMM_STATE;
+
+	reg = cpu_to_be32(data);
+	snd_motu_transaction_write(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
+				   sizeof(reg));
+}
+
+int snd_motu_stream_cache_packet_formats(struct snd_motu *motu)
+{
+	int err;
+
+	err = snd_motu_protocol_cache_packet_formats(motu);
+	if (err < 0)
+		return err;
+
+	if (motu->spec->flags & SND_MOTU_SPEC_TX_MIDI_2ND_Q) {
+		motu->tx_packet_formats.midi_flag_offset = 4;
+		motu->tx_packet_formats.midi_byte_offset = 6;
+	} else if (motu->spec->flags & SND_MOTU_SPEC_TX_MIDI_3RD_Q) {
+		motu->tx_packet_formats.midi_flag_offset = 8;
+		motu->tx_packet_formats.midi_byte_offset = 7;
+	}
+
+	if (motu->spec->flags & SND_MOTU_SPEC_RX_MIDI_2ND_Q) {
+		motu->rx_packet_formats.midi_flag_offset = 4;
+		motu->rx_packet_formats.midi_byte_offset = 6;
+	} else if (motu->spec->flags & SND_MOTU_SPEC_RX_MIDI_3RD_Q) {
+		motu->rx_packet_formats.midi_flag_offset = 8;
+		motu->rx_packet_formats.midi_byte_offset = 7;
+	}
+
+	return 0;
+}
+
+int snd_motu_stream_reserve_duplex(struct snd_motu *motu, unsigned int rate,
+				   unsigned int frames_per_period,
+				   unsigned int frames_per_buffer)
+{
+	unsigned int curr_rate;
+	int err;
+
+	err = snd_motu_protocol_get_clock_rate(motu, &curr_rate);
+	if (err < 0)
+		return err;
+	if (rate == 0)
+		rate = curr_rate;
+
+	if (motu->substreams_counter == 0 || curr_rate != rate) {
+		amdtp_domain_stop(&motu->domain);
+		finish_session(motu);
+
+		fw_iso_resources_free(&motu->tx_resources);
+		fw_iso_resources_free(&motu->rx_resources);
+
+		kfree(motu->cache.event_offsets);
+		motu->cache.event_offsets = NULL;
+
+		err = snd_motu_protocol_set_clock_rate(motu, rate);
+		if (err < 0) {
+			dev_err(&motu->unit->device,
+				"fail to set sampling rate: %d\n", err);
+			return err;
+		}
+
+		err = snd_motu_stream_cache_packet_formats(motu);
+		if (err < 0)
+			return err;
+
+		err = keep_resources(motu, rate, &motu->tx_stream);
+		if (err < 0)
+			return err;
+
+		err = keep_resources(motu, rate, &motu->rx_stream);
+		if (err < 0) {
+			fw_iso_resources_free(&motu->tx_resources);
+			return err;
+		}
+
+		err = amdtp_domain_set_events_per_period(&motu->domain,
+					frames_per_period, frames_per_buffer);
+		if (err < 0) {
+			fw_iso_resources_free(&motu->tx_resources);
+			fw_iso_resources_free(&motu->rx_resources);
+			return err;
+		}
+
+		motu->cache.size = motu->tx_stream.syt_interval * frames_per_buffer;
+		motu->cache.event_offsets = kcalloc(motu->cache.size, sizeof(*motu->cache.event_offsets),
+						  GFP_KERNEL);
+		if (!motu->cache.event_offsets) {
+			fw_iso_resources_free(&motu->tx_resources);
+			fw_iso_resources_free(&motu->rx_resources);
+			return -ENOMEM;
+		}
+	}
+
+	return 0;
+}
+
+static int ensure_packet_formats(struct snd_motu *motu)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, PACKET_FORMAT_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg);
+
+	data &= ~(TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS |
+		  RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS|
+		  TX_PACKET_TRANSMISSION_SPEED_MASK);
+	if (motu->spec->tx_fixed_pcm_chunks[0] == motu->tx_packet_formats.pcm_chunks[0])
+		data |= TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS;
+	if (motu->spec->rx_fixed_pcm_chunks[0] == motu->rx_packet_formats.pcm_chunks[0])
+		data |= RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS;
+	data |= fw_parent_device(motu->unit)->max_speed;
+
+	reg = cpu_to_be32(data);
+	return snd_motu_transaction_write(motu, PACKET_FORMAT_OFFSET, &reg,
+					  sizeof(reg));
+}
+
+int snd_motu_stream_start_duplex(struct snd_motu *motu)
+{
+	unsigned int generation = motu->rx_resources.generation;
+	int err = 0;
+
+	if (motu->substreams_counter == 0)
+		return 0;
+
+	if (amdtp_streaming_error(&motu->rx_stream) ||
+	    amdtp_streaming_error(&motu->tx_stream)) {
+		amdtp_domain_stop(&motu->domain);
+		finish_session(motu);
+	}
+
+	if (generation != fw_parent_device(motu->unit)->card->generation) {
+		err = fw_iso_resources_update(&motu->rx_resources);
+		if (err < 0)
+			return err;
+
+		err = fw_iso_resources_update(&motu->tx_resources);
+		if (err < 0)
+			return err;
+	}
+
+	if (!amdtp_stream_running(&motu->rx_stream)) {
+		int spd = fw_parent_device(motu->unit)->max_speed;
+
+		err = ensure_packet_formats(motu);
+		if (err < 0)
+			return err;
+
+		if (motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP) {
+			err = snd_motu_register_dsp_message_parser_init(motu);
+			if (err < 0)
+				return err;
+		} else if (motu->spec->flags & SND_MOTU_SPEC_COMMAND_DSP) {
+			err = snd_motu_command_dsp_message_parser_init(motu, motu->tx_stream.sfc);
+			if (err < 0)
+				return err;
+		}
+
+		err = begin_session(motu);
+		if (err < 0) {
+			dev_err(&motu->unit->device,
+				"fail to start isochronous comm: %d\n", err);
+			goto stop_streams;
+		}
+
+		err = amdtp_domain_add_stream(&motu->domain, &motu->tx_stream,
+					      motu->tx_resources.channel, spd);
+		if (err < 0)
+			goto stop_streams;
+
+		err = amdtp_domain_add_stream(&motu->domain, &motu->rx_stream,
+					      motu->rx_resources.channel, spd);
+		if (err < 0)
+			goto stop_streams;
+
+		motu->cache.tail = 0;
+		motu->cache.tx_cycle_count = UINT_MAX;
+		motu->cache.head = 0;
+		motu->cache.rx_cycle_count = UINT_MAX;
+
+		// NOTE: The device requires both of replay; the sequence of the number of data
+		// blocks per packet, and the sequence of source packet header per data block as
+		// presentation time.
+		err = amdtp_domain_start(&motu->domain, 0, true, false);
+		if (err < 0)
+			goto stop_streams;
+
+		if (!amdtp_domain_wait_ready(&motu->domain, READY_TIMEOUT_MS)) {
+			err = -ETIMEDOUT;
+			goto stop_streams;
+		}
+
+		err = snd_motu_protocol_switch_fetching_mode(motu, true);
+		if (err < 0) {
+			dev_err(&motu->unit->device,
+				"fail to enable frame fetching: %d\n", err);
+			goto stop_streams;
+		}
+	}
+
+	return 0;
+
+stop_streams:
+	amdtp_domain_stop(&motu->domain);
+	finish_session(motu);
+	return err;
+}
+
+void snd_motu_stream_stop_duplex(struct snd_motu *motu)
+{
+	if (motu->substreams_counter == 0) {
+		amdtp_domain_stop(&motu->domain);
+		finish_session(motu);
+
+		fw_iso_resources_free(&motu->tx_resources);
+		fw_iso_resources_free(&motu->rx_resources);
+
+		kfree(motu->cache.event_offsets);
+		motu->cache.event_offsets = NULL;
+	}
+}
+
+static int init_stream(struct snd_motu *motu, struct amdtp_stream *s)
+{
+	struct fw_iso_resources *resources;
+	enum amdtp_stream_direction dir;
+	int err;
+
+	if (s == &motu->tx_stream) {
+		resources = &motu->tx_resources;
+		dir = AMDTP_IN_STREAM;
+	} else {
+		resources = &motu->rx_resources;
+		dir = AMDTP_OUT_STREAM;
+	}
+
+	err = fw_iso_resources_init(resources, motu->unit);
+	if (err < 0)
+		return err;
+
+	err = amdtp_motu_init(s, motu->unit, dir, motu->spec, &motu->cache);
+	if (err < 0)
+		fw_iso_resources_destroy(resources);
+
+	return err;
+}
+
+static void destroy_stream(struct snd_motu *motu, struct amdtp_stream *s)
+{
+	amdtp_stream_destroy(s);
+
+	if (s == &motu->tx_stream)
+		fw_iso_resources_destroy(&motu->tx_resources);
+	else
+		fw_iso_resources_destroy(&motu->rx_resources);
+}
+
+int snd_motu_stream_init_duplex(struct snd_motu *motu)
+{
+	int err;
+
+	err = init_stream(motu, &motu->tx_stream);
+	if (err < 0)
+		return err;
+
+	err = init_stream(motu, &motu->rx_stream);
+	if (err < 0) {
+		destroy_stream(motu, &motu->tx_stream);
+		return err;
+	}
+
+	err = amdtp_domain_init(&motu->domain);
+	if (err < 0) {
+		destroy_stream(motu, &motu->tx_stream);
+		destroy_stream(motu, &motu->rx_stream);
+	}
+
+	return err;
+}
+
+// This function should be called before starting streams or after stopping
+// streams.
+void snd_motu_stream_destroy_duplex(struct snd_motu *motu)
+{
+	amdtp_domain_destroy(&motu->domain);
+
+	destroy_stream(motu, &motu->rx_stream);
+	destroy_stream(motu, &motu->tx_stream);
+
+	motu->substreams_counter = 0;
+}
+
+static void motu_lock_changed(struct snd_motu *motu)
+{
+	motu->dev_lock_changed = true;
+	wake_up(&motu->hwdep_wait);
+}
+
+int snd_motu_stream_lock_try(struct snd_motu *motu)
+{
+	int err;
+
+	spin_lock_irq(&motu->lock);
+
+	if (motu->dev_lock_count < 0) {
+		err = -EBUSY;
+		goto out;
+	}
+
+	if (motu->dev_lock_count++ == 0)
+		motu_lock_changed(motu);
+	err = 0;
+out:
+	spin_unlock_irq(&motu->lock);
+	return err;
+}
+
+void snd_motu_stream_lock_release(struct snd_motu *motu)
+{
+	spin_lock_irq(&motu->lock);
+
+	if (WARN_ON(motu->dev_lock_count <= 0))
+		goto out;
+
+	if (--motu->dev_lock_count == 0)
+		motu_lock_changed(motu);
+out:
+	spin_unlock_irq(&motu->lock);
+}