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, 683 insertions, 0 deletions

diff --git a/sound/usb/6fire/pcm.c b/sound/usb/6fire/pcm.c
new file mode 100644
index 000000000..32c39d8bd
--- /dev/null
+++ b/sound/usb/6fire/pcm.c
@@ -0,0 +1,683 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Linux driver for TerraTec DMX 6Fire USB
+ *
+ * PCM driver
+ *
+ * Author:	Torsten Schenk <torsten.schenk@zoho.com>
+ * Created:	Jan 01, 2011
+ * Copyright:	(C) Torsten Schenk
+ */
+
+#include "pcm.h"
+#include "chip.h"
+#include "comm.h"
+#include "control.h"
+
+enum {
+	OUT_N_CHANNELS = 6, IN_N_CHANNELS = 4
+};
+
+/* keep next two synced with
+ * FW_EP_W_MAX_PACKET_SIZE[] and RATES_MAX_PACKET_SIZE
+ * and CONTROL_RATE_XXX in control.h */
+static const int rates_in_packet_size[] = { 228, 228, 420, 420, 404, 404 };
+static const int rates_out_packet_size[] = { 228, 228, 420, 420, 604, 604 };
+static const int rates[] = { 44100, 48000, 88200, 96000, 176400, 192000 };
+static const int rates_alsaid[] = {
+	SNDRV_PCM_RATE_44100, SNDRV_PCM_RATE_48000,
+	SNDRV_PCM_RATE_88200, SNDRV_PCM_RATE_96000,
+	SNDRV_PCM_RATE_176400, SNDRV_PCM_RATE_192000 };
+
+enum { /* settings for pcm */
+	OUT_EP = 6, IN_EP = 2, MAX_BUFSIZE = 128 * 1024
+};
+
+enum { /* pcm streaming states */
+	STREAM_DISABLED, /* no pcm streaming */
+	STREAM_STARTING, /* pcm streaming requested, waiting to become ready */
+	STREAM_RUNNING, /* pcm streaming running */
+	STREAM_STOPPING
+};
+
+static const struct snd_pcm_hardware pcm_hw = {
+	.info = SNDRV_PCM_INFO_MMAP |
+		SNDRV_PCM_INFO_INTERLEAVED |
+		SNDRV_PCM_INFO_BLOCK_TRANSFER |
+		SNDRV_PCM_INFO_MMAP_VALID |
+		SNDRV_PCM_INFO_BATCH,
+
+	.formats = SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE,
+
+	.rates = SNDRV_PCM_RATE_44100 |
+		SNDRV_PCM_RATE_48000 |
+		SNDRV_PCM_RATE_88200 |
+		SNDRV_PCM_RATE_96000 |
+		SNDRV_PCM_RATE_176400 |
+		SNDRV_PCM_RATE_192000,
+
+	.rate_min = 44100,
+	.rate_max = 192000,
+	.channels_min = 1,
+	.channels_max = 0, /* set in pcm_open, depending on capture/playback */
+	.buffer_bytes_max = MAX_BUFSIZE,
+	.period_bytes_min = PCM_N_PACKETS_PER_URB * (PCM_MAX_PACKET_SIZE - 4),
+	.period_bytes_max = MAX_BUFSIZE,
+	.periods_min = 2,
+	.periods_max = 1024
+};
+
+static int usb6fire_pcm_set_rate(struct pcm_runtime *rt)
+{
+	int ret;
+	struct control_runtime *ctrl_rt = rt->chip->control;
+
+	ctrl_rt->usb_streaming = false;
+	ret = ctrl_rt->update_streaming(ctrl_rt);
+	if (ret < 0) {
+		dev_err(&rt->chip->dev->dev,
+			"error stopping streaming while setting samplerate %d.\n",
+			rates[rt->rate]);
+		return ret;
+	}
+
+	ret = ctrl_rt->set_rate(ctrl_rt, rt->rate);
+	if (ret < 0) {
+		dev_err(&rt->chip->dev->dev,
+			"error setting samplerate %d.\n",
+			rates[rt->rate]);
+		return ret;
+	}
+
+	ret = ctrl_rt->set_channels(ctrl_rt, OUT_N_CHANNELS, IN_N_CHANNELS,
+			false, false);
+	if (ret < 0) {
+		dev_err(&rt->chip->dev->dev,
+			"error initializing channels while setting samplerate %d.\n",
+			rates[rt->rate]);
+		return ret;
+	}
+
+	ctrl_rt->usb_streaming = true;
+	ret = ctrl_rt->update_streaming(ctrl_rt);
+	if (ret < 0) {
+		dev_err(&rt->chip->dev->dev,
+			"error starting streaming while setting samplerate %d.\n",
+			rates[rt->rate]);
+		return ret;
+	}
+
+	rt->in_n_analog = IN_N_CHANNELS;
+	rt->out_n_analog = OUT_N_CHANNELS;
+	rt->in_packet_size = rates_in_packet_size[rt->rate];
+	rt->out_packet_size = rates_out_packet_size[rt->rate];
+	return 0;
+}
+
+static struct pcm_substream *usb6fire_pcm_get_substream(
+		struct snd_pcm_substream *alsa_sub)
+{
+	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
+
+	if (alsa_sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		return &rt->playback;
+	else if (alsa_sub->stream == SNDRV_PCM_STREAM_CAPTURE)
+		return &rt->capture;
+	dev_err(&rt->chip->dev->dev, "error getting pcm substream slot.\n");
+	return NULL;
+}
+
+/* call with stream_mutex locked */
+static void usb6fire_pcm_stream_stop(struct pcm_runtime *rt)
+{
+	int i;
+	struct control_runtime *ctrl_rt = rt->chip->control;
+
+	if (rt->stream_state != STREAM_DISABLED) {
+
+		rt->stream_state = STREAM_STOPPING;
+
+		for (i = 0; i < PCM_N_URBS; i++) {
+			usb_kill_urb(&rt->in_urbs[i].instance);
+			usb_kill_urb(&rt->out_urbs[i].instance);
+		}
+		ctrl_rt->usb_streaming = false;
+		ctrl_rt->update_streaming(ctrl_rt);
+		rt->stream_state = STREAM_DISABLED;
+	}
+}
+
+/* call with stream_mutex locked */
+static int usb6fire_pcm_stream_start(struct pcm_runtime *rt)
+{
+	int ret;
+	int i;
+	int k;
+	struct usb_iso_packet_descriptor *packet;
+
+	if (rt->stream_state == STREAM_DISABLED) {
+		/* submit our in urbs */
+		rt->stream_wait_cond = false;
+		rt->stream_state = STREAM_STARTING;
+		for (i = 0; i < PCM_N_URBS; i++) {
+			for (k = 0; k < PCM_N_PACKETS_PER_URB; k++) {
+				packet = &rt->in_urbs[i].packets[k];
+				packet->offset = k * rt->in_packet_size;
+				packet->length = rt->in_packet_size;
+				packet->actual_length = 0;
+				packet->status = 0;
+			}
+			ret = usb_submit_urb(&rt->in_urbs[i].instance,
+					GFP_ATOMIC);
+			if (ret) {
+				usb6fire_pcm_stream_stop(rt);
+				return ret;
+			}
+		}
+
+		/* wait for first out urb to return (sent in urb handler) */
+		wait_event_timeout(rt->stream_wait_queue, rt->stream_wait_cond,
+				HZ);
+		if (rt->stream_wait_cond)
+			rt->stream_state = STREAM_RUNNING;
+		else {
+			usb6fire_pcm_stream_stop(rt);
+			return -EIO;
+		}
+	}
+	return 0;
+}
+
+/* call with substream locked */
+static void usb6fire_pcm_capture(struct pcm_substream *sub, struct pcm_urb *urb)
+{
+	int i;
+	int frame;
+	int frame_count;
+	unsigned int total_length = 0;
+	struct pcm_runtime *rt = snd_pcm_substream_chip(sub->instance);
+	struct snd_pcm_runtime *alsa_rt = sub->instance->runtime;
+	u32 *src = NULL;
+	u32 *dest = (u32 *) (alsa_rt->dma_area + sub->dma_off
+			* (alsa_rt->frame_bits >> 3));
+	u32 *dest_end = (u32 *) (alsa_rt->dma_area + alsa_rt->buffer_size
+			* (alsa_rt->frame_bits >> 3));
+	int bytes_per_frame = alsa_rt->channels << 2;
+
+	for (i = 0; i < PCM_N_PACKETS_PER_URB; i++) {
+		/* at least 4 header bytes for valid packet.
+		 * after that: 32 bits per sample for analog channels */
+		if (urb->packets[i].actual_length > 4)
+			frame_count = (urb->packets[i].actual_length - 4)
+					/ (rt->in_n_analog << 2);
+		else
+			frame_count = 0;
+
+		if (alsa_rt->format == SNDRV_PCM_FORMAT_S24_LE)
+			src = (u32 *) (urb->buffer + total_length);
+		else if (alsa_rt->format == SNDRV_PCM_FORMAT_S32_LE)
+			src = (u32 *) (urb->buffer - 1 + total_length);
+		else
+			return;
+		src++; /* skip leading 4 bytes of every packet */
+		total_length += urb->packets[i].length;
+		for (frame = 0; frame < frame_count; frame++) {
+			memcpy(dest, src, bytes_per_frame);
+			dest += alsa_rt->channels;
+			src += rt->in_n_analog;
+			sub->dma_off++;
+			sub->period_off++;
+			if (dest == dest_end) {
+				sub->dma_off = 0;
+				dest = (u32 *) alsa_rt->dma_area;
+			}
+		}
+	}
+}
+
+/* call with substream locked */
+static void usb6fire_pcm_playback(struct pcm_substream *sub,
+		struct pcm_urb *urb)
+{
+	int i;
+	int frame;
+	int frame_count;
+	struct pcm_runtime *rt = snd_pcm_substream_chip(sub->instance);
+	struct snd_pcm_runtime *alsa_rt = sub->instance->runtime;
+	u32 *src = (u32 *) (alsa_rt->dma_area + sub->dma_off
+			* (alsa_rt->frame_bits >> 3));
+	u32 *src_end = (u32 *) (alsa_rt->dma_area + alsa_rt->buffer_size
+			* (alsa_rt->frame_bits >> 3));
+	u32 *dest;
+	int bytes_per_frame = alsa_rt->channels << 2;
+
+	if (alsa_rt->format == SNDRV_PCM_FORMAT_S32_LE)
+		dest = (u32 *) (urb->buffer - 1);
+	else if (alsa_rt->format == SNDRV_PCM_FORMAT_S24_LE)
+		dest = (u32 *) (urb->buffer);
+	else {
+		dev_err(&rt->chip->dev->dev, "Unknown sample format.");
+		return;
+	}
+
+	for (i = 0; i < PCM_N_PACKETS_PER_URB; i++) {
+		/* at least 4 header bytes for valid packet.
+		 * after that: 32 bits per sample for analog channels */
+		if (urb->packets[i].length > 4)
+			frame_count = (urb->packets[i].length - 4)
+					/ (rt->out_n_analog << 2);
+		else
+			frame_count = 0;
+		dest++; /* skip leading 4 bytes of every frame */
+		for (frame = 0; frame < frame_count; frame++) {
+			memcpy(dest, src, bytes_per_frame);
+			src += alsa_rt->channels;
+			dest += rt->out_n_analog;
+			sub->dma_off++;
+			sub->period_off++;
+			if (src == src_end) {
+				src = (u32 *) alsa_rt->dma_area;
+				sub->dma_off = 0;
+			}
+		}
+	}
+}
+
+static void usb6fire_pcm_in_urb_handler(struct urb *usb_urb)
+{
+	struct pcm_urb *in_urb = usb_urb->context;
+	struct pcm_urb *out_urb = in_urb->peer;
+	struct pcm_runtime *rt = in_urb->chip->pcm;
+	struct pcm_substream *sub;
+	unsigned long flags;
+	int total_length = 0;
+	int frame_count;
+	int frame;
+	int channel;
+	int i;
+	u8 *dest;
+
+	if (usb_urb->status || rt->panic || rt->stream_state == STREAM_STOPPING)
+		return;
+	for (i = 0; i < PCM_N_PACKETS_PER_URB; i++)
+		if (in_urb->packets[i].status) {
+			rt->panic = true;
+			return;
+		}
+
+	if (rt->stream_state == STREAM_DISABLED) {
+		dev_err(&rt->chip->dev->dev,
+			"internal error: stream disabled in in-urb handler.\n");
+		return;
+	}
+
+	/* receive our capture data */
+	sub = &rt->capture;
+	spin_lock_irqsave(&sub->lock, flags);
+	if (sub->active) {
+		usb6fire_pcm_capture(sub, in_urb);
+		if (sub->period_off >= sub->instance->runtime->period_size) {
+			sub->period_off %= sub->instance->runtime->period_size;
+			spin_unlock_irqrestore(&sub->lock, flags);
+			snd_pcm_period_elapsed(sub->instance);
+		} else
+			spin_unlock_irqrestore(&sub->lock, flags);
+	} else
+		spin_unlock_irqrestore(&sub->lock, flags);
+
+	/* setup out urb structure */
+	for (i = 0; i < PCM_N_PACKETS_PER_URB; i++) {
+		out_urb->packets[i].offset = total_length;
+		out_urb->packets[i].length = (in_urb->packets[i].actual_length
+				- 4) / (rt->in_n_analog << 2)
+				* (rt->out_n_analog << 2) + 4;
+		out_urb->packets[i].status = 0;
+		total_length += out_urb->packets[i].length;
+	}
+	memset(out_urb->buffer, 0, total_length);
+
+	/* now send our playback data (if a free out urb was found) */
+	sub = &rt->playback;
+	spin_lock_irqsave(&sub->lock, flags);
+	if (sub->active) {
+		usb6fire_pcm_playback(sub, out_urb);
+		if (sub->period_off >= sub->instance->runtime->period_size) {
+			sub->period_off %= sub->instance->runtime->period_size;
+			spin_unlock_irqrestore(&sub->lock, flags);
+			snd_pcm_period_elapsed(sub->instance);
+		} else
+			spin_unlock_irqrestore(&sub->lock, flags);
+	} else
+		spin_unlock_irqrestore(&sub->lock, flags);
+
+	/* setup the 4th byte of each sample (0x40 for analog channels) */
+	dest = out_urb->buffer;
+	for (i = 0; i < PCM_N_PACKETS_PER_URB; i++)
+		if (out_urb->packets[i].length >= 4) {
+			frame_count = (out_urb->packets[i].length - 4)
+					/ (rt->out_n_analog << 2);
+			*(dest++) = 0xaa;
+			*(dest++) = 0xaa;
+			*(dest++) = frame_count;
+			*(dest++) = 0x00;
+			for (frame = 0; frame < frame_count; frame++)
+				for (channel = 0;
+						channel < rt->out_n_analog;
+						channel++) {
+					dest += 3; /* skip sample data */
+					*(dest++) = 0x40;
+				}
+		}
+	usb_submit_urb(&out_urb->instance, GFP_ATOMIC);
+	usb_submit_urb(&in_urb->instance, GFP_ATOMIC);
+}
+
+static void usb6fire_pcm_out_urb_handler(struct urb *usb_urb)
+{
+	struct pcm_urb *urb = usb_urb->context;
+	struct pcm_runtime *rt = urb->chip->pcm;
+
+	if (rt->stream_state == STREAM_STARTING) {
+		rt->stream_wait_cond = true;
+		wake_up(&rt->stream_wait_queue);
+	}
+}
+
+static int usb6fire_pcm_open(struct snd_pcm_substream *alsa_sub)
+{
+	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
+	struct pcm_substream *sub = NULL;
+	struct snd_pcm_runtime *alsa_rt = alsa_sub->runtime;
+
+	if (rt->panic)
+		return -EPIPE;
+
+	mutex_lock(&rt->stream_mutex);
+	alsa_rt->hw = pcm_hw;
+
+	if (alsa_sub->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		if (rt->rate < ARRAY_SIZE(rates))
+			alsa_rt->hw.rates = rates_alsaid[rt->rate];
+		alsa_rt->hw.channels_max = OUT_N_CHANNELS;
+		sub = &rt->playback;
+	} else if (alsa_sub->stream == SNDRV_PCM_STREAM_CAPTURE) {
+		if (rt->rate < ARRAY_SIZE(rates))
+			alsa_rt->hw.rates = rates_alsaid[rt->rate];
+		alsa_rt->hw.channels_max = IN_N_CHANNELS;
+		sub = &rt->capture;
+	}
+
+	if (!sub) {
+		mutex_unlock(&rt->stream_mutex);
+		dev_err(&rt->chip->dev->dev, "invalid stream type.\n");
+		return -EINVAL;
+	}
+
+	sub->instance = alsa_sub;
+	sub->active = false;
+	mutex_unlock(&rt->stream_mutex);
+	return 0;
+}
+
+static int usb6fire_pcm_close(struct snd_pcm_substream *alsa_sub)
+{
+	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
+	struct pcm_substream *sub = usb6fire_pcm_get_substream(alsa_sub);
+	unsigned long flags;
+
+	if (rt->panic)
+		return 0;
+
+	mutex_lock(&rt->stream_mutex);
+	if (sub) {
+		/* deactivate substream */
+		spin_lock_irqsave(&sub->lock, flags);
+		sub->instance = NULL;
+		sub->active = false;
+		spin_unlock_irqrestore(&sub->lock, flags);
+
+		/* all substreams closed? if so, stop streaming */
+		if (!rt->playback.instance && !rt->capture.instance) {
+			usb6fire_pcm_stream_stop(rt);
+			rt->rate = ARRAY_SIZE(rates);
+		}
+	}
+	mutex_unlock(&rt->stream_mutex);
+	return 0;
+}
+
+static int usb6fire_pcm_prepare(struct snd_pcm_substream *alsa_sub)
+{
+	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
+	struct pcm_substream *sub = usb6fire_pcm_get_substream(alsa_sub);
+	struct snd_pcm_runtime *alsa_rt = alsa_sub->runtime;
+	int ret;
+
+	if (rt->panic)
+		return -EPIPE;
+	if (!sub)
+		return -ENODEV;
+
+	mutex_lock(&rt->stream_mutex);
+	sub->dma_off = 0;
+	sub->period_off = 0;
+
+	if (rt->stream_state == STREAM_DISABLED) {
+		for (rt->rate = 0; rt->rate < ARRAY_SIZE(rates); rt->rate++)
+			if (alsa_rt->rate == rates[rt->rate])
+				break;
+		if (rt->rate == ARRAY_SIZE(rates)) {
+			mutex_unlock(&rt->stream_mutex);
+			dev_err(&rt->chip->dev->dev,
+				"invalid rate %d in prepare.\n",
+				alsa_rt->rate);
+			return -EINVAL;
+		}
+
+		ret = usb6fire_pcm_set_rate(rt);
+		if (ret) {
+			mutex_unlock(&rt->stream_mutex);
+			return ret;
+		}
+		ret = usb6fire_pcm_stream_start(rt);
+		if (ret) {
+			mutex_unlock(&rt->stream_mutex);
+			dev_err(&rt->chip->dev->dev,
+				"could not start pcm stream.\n");
+			return ret;
+		}
+	}
+	mutex_unlock(&rt->stream_mutex);
+	return 0;
+}
+
+static int usb6fire_pcm_trigger(struct snd_pcm_substream *alsa_sub, int cmd)
+{
+	struct pcm_substream *sub = usb6fire_pcm_get_substream(alsa_sub);
+	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
+	unsigned long flags;
+
+	if (rt->panic)
+		return -EPIPE;
+	if (!sub)
+		return -ENODEV;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		spin_lock_irqsave(&sub->lock, flags);
+		sub->active = true;
+		spin_unlock_irqrestore(&sub->lock, flags);
+		return 0;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		spin_lock_irqsave(&sub->lock, flags);
+		sub->active = false;
+		spin_unlock_irqrestore(&sub->lock, flags);
+		return 0;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static snd_pcm_uframes_t usb6fire_pcm_pointer(
+		struct snd_pcm_substream *alsa_sub)
+{
+	struct pcm_substream *sub = usb6fire_pcm_get_substream(alsa_sub);
+	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
+	unsigned long flags;
+	snd_pcm_uframes_t ret;
+
+	if (rt->panic || !sub)
+		return SNDRV_PCM_POS_XRUN;
+
+	spin_lock_irqsave(&sub->lock, flags);
+	ret = sub->dma_off;
+	spin_unlock_irqrestore(&sub->lock, flags);
+	return ret;
+}
+
+static const struct snd_pcm_ops pcm_ops = {
+	.open = usb6fire_pcm_open,
+	.close = usb6fire_pcm_close,
+	.prepare = usb6fire_pcm_prepare,
+	.trigger = usb6fire_pcm_trigger,
+	.pointer = usb6fire_pcm_pointer,
+};
+
+static void usb6fire_pcm_init_urb(struct pcm_urb *urb,
+				  struct sfire_chip *chip, bool in, int ep,
+				  void (*handler)(struct urb *))
+{
+	urb->chip = chip;
+	usb_init_urb(&urb->instance);
+	urb->instance.transfer_buffer = urb->buffer;
+	urb->instance.transfer_buffer_length =
+			PCM_N_PACKETS_PER_URB * PCM_MAX_PACKET_SIZE;
+	urb->instance.dev = chip->dev;
+	urb->instance.pipe = in ? usb_rcvisocpipe(chip->dev, ep)
+			: usb_sndisocpipe(chip->dev, ep);
+	urb->instance.interval = 1;
+	urb->instance.complete = handler;
+	urb->instance.context = urb;
+	urb->instance.number_of_packets = PCM_N_PACKETS_PER_URB;
+}
+
+static int usb6fire_pcm_buffers_init(struct pcm_runtime *rt)
+{
+	int i;
+
+	for (i = 0; i < PCM_N_URBS; i++) {
+		rt->out_urbs[i].buffer = kcalloc(PCM_MAX_PACKET_SIZE,
+						 PCM_N_PACKETS_PER_URB,
+						 GFP_KERNEL);
+		if (!rt->out_urbs[i].buffer)
+			return -ENOMEM;
+		rt->in_urbs[i].buffer = kcalloc(PCM_MAX_PACKET_SIZE,
+						PCM_N_PACKETS_PER_URB,
+						GFP_KERNEL);
+		if (!rt->in_urbs[i].buffer)
+			return -ENOMEM;
+	}
+	return 0;
+}
+
+static void usb6fire_pcm_buffers_destroy(struct pcm_runtime *rt)
+{
+	int i;
+
+	for (i = 0; i < PCM_N_URBS; i++) {
+		kfree(rt->out_urbs[i].buffer);
+		kfree(rt->in_urbs[i].buffer);
+	}
+}
+
+int usb6fire_pcm_init(struct sfire_chip *chip)
+{
+	int i;
+	int ret;
+	struct snd_pcm *pcm;
+	struct pcm_runtime *rt =
+			kzalloc(sizeof(struct pcm_runtime), GFP_KERNEL);
+
+	if (!rt)
+		return -ENOMEM;
+
+	ret = usb6fire_pcm_buffers_init(rt);
+	if (ret) {
+		usb6fire_pcm_buffers_destroy(rt);
+		kfree(rt);
+		return ret;
+	}
+
+	rt->chip = chip;
+	rt->stream_state = STREAM_DISABLED;
+	rt->rate = ARRAY_SIZE(rates);
+	init_waitqueue_head(&rt->stream_wait_queue);
+	mutex_init(&rt->stream_mutex);
+
+	spin_lock_init(&rt->playback.lock);
+	spin_lock_init(&rt->capture.lock);
+
+	for (i = 0; i < PCM_N_URBS; i++) {
+		usb6fire_pcm_init_urb(&rt->in_urbs[i], chip, true, IN_EP,
+				usb6fire_pcm_in_urb_handler);
+		usb6fire_pcm_init_urb(&rt->out_urbs[i], chip, false, OUT_EP,
+				usb6fire_pcm_out_urb_handler);
+
+		rt->in_urbs[i].peer = &rt->out_urbs[i];
+		rt->out_urbs[i].peer = &rt->in_urbs[i];
+	}
+
+	ret = snd_pcm_new(chip->card, "DMX6FireUSB", 0, 1, 1, &pcm);
+	if (ret < 0) {
+		usb6fire_pcm_buffers_destroy(rt);
+		kfree(rt);
+		dev_err(&chip->dev->dev, "cannot create pcm instance.\n");
+		return ret;
+	}
+
+	pcm->private_data = rt;
+	strcpy(pcm->name, "DMX 6Fire USB");
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &pcm_ops);
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &pcm_ops);
+	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC, NULL, 0, 0);
+
+	rt->instance = pcm;
+
+	chip->pcm = rt;
+	return 0;
+}
+
+void usb6fire_pcm_abort(struct sfire_chip *chip)
+{
+	struct pcm_runtime *rt = chip->pcm;
+	int i;
+
+	if (rt) {
+		rt->panic = true;
+
+		if (rt->playback.instance)
+			snd_pcm_stop_xrun(rt->playback.instance);
+
+		if (rt->capture.instance)
+			snd_pcm_stop_xrun(rt->capture.instance);
+
+		for (i = 0; i < PCM_N_URBS; i++) {
+			usb_poison_urb(&rt->in_urbs[i].instance);
+			usb_poison_urb(&rt->out_urbs[i].instance);
+		}
+
+	}
+}
+
+void usb6fire_pcm_destroy(struct sfire_chip *chip)
+{
+	struct pcm_runtime *rt = chip->pcm;
+
+	usb6fire_pcm_buffers_destroy(rt);
+	kfree(rt);
+	chip->pcm = NULL;
+}