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, 738 insertions, 0 deletions

diff --git a/sound/firewire/isight.c b/sound/firewire/isight.c
new file mode 100644
index 000000000..6655af53b
--- /dev/null
+++ b/sound/firewire/isight.c
@@ -0,0 +1,738 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Apple iSight audio driver
+ *
+ * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
+ */
+
+#include <asm/byteorder.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/firewire.h>
+#include <linux/firewire-constants.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
+#include <linux/string.h>
+#include <sound/control.h>
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+#include <sound/tlv.h>
+#include "lib.h"
+#include "iso-resources.h"
+#include "packets-buffer.h"
+
+#define OUI_APPLE		0x000a27
+#define MODEL_APPLE_ISIGHT	0x000008
+#define SW_ISIGHT_AUDIO		0x000010
+
+#define REG_AUDIO_ENABLE	0x000
+#define  AUDIO_ENABLE		0x80000000
+#define REG_DEF_AUDIO_GAIN	0x204
+#define REG_GAIN_RAW_START	0x210
+#define REG_GAIN_RAW_END	0x214
+#define REG_GAIN_DB_START	0x218
+#define REG_GAIN_DB_END		0x21c
+#define REG_SAMPLE_RATE_INQUIRY	0x280
+#define REG_ISO_TX_CONFIG	0x300
+#define  SPEED_SHIFT		16
+#define REG_SAMPLE_RATE		0x400
+#define  RATE_48000		0x80000000
+#define REG_GAIN		0x500
+#define REG_MUTE		0x504
+
+#define MAX_FRAMES_PER_PACKET	475
+
+#define QUEUE_LENGTH		20
+
+struct isight {
+	struct snd_card *card;
+	struct fw_unit *unit;
+	struct fw_device *device;
+	u64 audio_base;
+	struct snd_pcm_substream *pcm;
+	struct mutex mutex;
+	struct iso_packets_buffer buffer;
+	struct fw_iso_resources resources;
+	struct fw_iso_context *context;
+	bool pcm_active;
+	bool pcm_running;
+	bool first_packet;
+	int packet_index;
+	u32 total_samples;
+	unsigned int buffer_pointer;
+	unsigned int period_counter;
+	s32 gain_min, gain_max;
+	unsigned int gain_tlv[4];
+};
+
+struct audio_payload {
+	__be32 sample_count;
+	__be32 signature;
+	__be32 sample_total;
+	__be32 reserved;
+	__be16 samples[2 * MAX_FRAMES_PER_PACKET];
+};
+
+MODULE_DESCRIPTION("iSight audio driver");
+MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
+MODULE_LICENSE("GPL v2");
+
+static struct fw_iso_packet audio_packet = {
+	.payload_length = sizeof(struct audio_payload),
+	.interrupt = 1,
+	.header_length = 4,
+};
+
+static void isight_update_pointers(struct isight *isight, unsigned int count)
+{
+	struct snd_pcm_runtime *runtime = isight->pcm->runtime;
+	unsigned int ptr;
+
+	smp_wmb(); /* update buffer data before buffer pointer */
+
+	ptr = isight->buffer_pointer;
+	ptr += count;
+	if (ptr >= runtime->buffer_size)
+		ptr -= runtime->buffer_size;
+	WRITE_ONCE(isight->buffer_pointer, ptr);
+
+	isight->period_counter += count;
+	if (isight->period_counter >= runtime->period_size) {
+		isight->period_counter -= runtime->period_size;
+		snd_pcm_period_elapsed(isight->pcm);
+	}
+}
+
+static void isight_samples(struct isight *isight,
+			   const __be16 *samples, unsigned int count)
+{
+	struct snd_pcm_runtime *runtime;
+	unsigned int count1;
+
+	if (!READ_ONCE(isight->pcm_running))
+		return;
+
+	runtime = isight->pcm->runtime;
+	if (isight->buffer_pointer + count <= runtime->buffer_size) {
+		memcpy(runtime->dma_area + isight->buffer_pointer * 4,
+		       samples, count * 4);
+	} else {
+		count1 = runtime->buffer_size - isight->buffer_pointer;
+		memcpy(runtime->dma_area + isight->buffer_pointer * 4,
+		       samples, count1 * 4);
+		samples += count1 * 2;
+		memcpy(runtime->dma_area, samples, (count - count1) * 4);
+	}
+
+	isight_update_pointers(isight, count);
+}
+
+static void isight_pcm_abort(struct isight *isight)
+{
+	if (READ_ONCE(isight->pcm_active))
+		snd_pcm_stop_xrun(isight->pcm);
+}
+
+static void isight_dropped_samples(struct isight *isight, unsigned int total)
+{
+	struct snd_pcm_runtime *runtime;
+	u32 dropped;
+	unsigned int count1;
+
+	if (!READ_ONCE(isight->pcm_running))
+		return;
+
+	runtime = isight->pcm->runtime;
+	dropped = total - isight->total_samples;
+	if (dropped < runtime->buffer_size) {
+		if (isight->buffer_pointer + dropped <= runtime->buffer_size) {
+			memset(runtime->dma_area + isight->buffer_pointer * 4,
+			       0, dropped * 4);
+		} else {
+			count1 = runtime->buffer_size - isight->buffer_pointer;
+			memset(runtime->dma_area + isight->buffer_pointer * 4,
+			       0, count1 * 4);
+			memset(runtime->dma_area, 0, (dropped - count1) * 4);
+		}
+		isight_update_pointers(isight, dropped);
+	} else {
+		isight_pcm_abort(isight);
+	}
+}
+
+static void isight_packet(struct fw_iso_context *context, u32 cycle,
+			  size_t header_length, void *header, void *data)
+{
+	struct isight *isight = data;
+	const struct audio_payload *payload;
+	unsigned int index, length, count, total;
+	int err;
+
+	if (isight->packet_index < 0)
+		return;
+	index = isight->packet_index;
+	payload = isight->buffer.packets[index].buffer;
+	length = be32_to_cpup(header) >> 16;
+
+	if (likely(length >= 16 &&
+		   payload->signature == cpu_to_be32(0x73676874/*"sght"*/))) {
+		count = be32_to_cpu(payload->sample_count);
+		if (likely(count <= (length - 16) / 4)) {
+			total = be32_to_cpu(payload->sample_total);
+			if (unlikely(total != isight->total_samples)) {
+				if (!isight->first_packet)
+					isight_dropped_samples(isight, total);
+				isight->first_packet = false;
+				isight->total_samples = total;
+			}
+
+			isight_samples(isight, payload->samples, count);
+			isight->total_samples += count;
+		}
+	}
+
+	err = fw_iso_context_queue(isight->context, &audio_packet,
+				   &isight->buffer.iso_buffer,
+				   isight->buffer.packets[index].offset);
+	if (err < 0) {
+		dev_err(&isight->unit->device, "queueing error: %d\n", err);
+		isight_pcm_abort(isight);
+		isight->packet_index = -1;
+		return;
+	}
+	fw_iso_context_queue_flush(isight->context);
+
+	if (++index >= QUEUE_LENGTH)
+		index = 0;
+	isight->packet_index = index;
+}
+
+static int isight_connect(struct isight *isight)
+{
+	int ch, err;
+	__be32 value;
+
+retry_after_bus_reset:
+	ch = fw_iso_resources_allocate(&isight->resources,
+				       sizeof(struct audio_payload),
+				       isight->device->max_speed);
+	if (ch < 0) {
+		err = ch;
+		goto error;
+	}
+
+	value = cpu_to_be32(ch | (isight->device->max_speed << SPEED_SHIFT));
+	err = snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
+				 isight->audio_base + REG_ISO_TX_CONFIG,
+				 &value, 4, FW_FIXED_GENERATION |
+				 isight->resources.generation);
+	if (err == -EAGAIN) {
+		fw_iso_resources_free(&isight->resources);
+		goto retry_after_bus_reset;
+	} else if (err < 0) {
+		goto err_resources;
+	}
+
+	return 0;
+
+err_resources:
+	fw_iso_resources_free(&isight->resources);
+error:
+	return err;
+}
+
+static int isight_open(struct snd_pcm_substream *substream)
+{
+	static const struct snd_pcm_hardware hardware = {
+		.info = SNDRV_PCM_INFO_MMAP |
+			SNDRV_PCM_INFO_MMAP_VALID |
+			SNDRV_PCM_INFO_BATCH |
+			SNDRV_PCM_INFO_INTERLEAVED |
+			SNDRV_PCM_INFO_BLOCK_TRANSFER,
+		.formats = SNDRV_PCM_FMTBIT_S16_BE,
+		.rates = SNDRV_PCM_RATE_48000,
+		.rate_min = 48000,
+		.rate_max = 48000,
+		.channels_min = 2,
+		.channels_max = 2,
+		.buffer_bytes_max = 4 * 1024 * 1024,
+		.period_bytes_min = MAX_FRAMES_PER_PACKET * 4,
+		.period_bytes_max = 1024 * 1024,
+		.periods_min = 2,
+		.periods_max = UINT_MAX,
+	};
+	struct isight *isight = substream->private_data;
+
+	substream->runtime->hw = hardware;
+
+	return iso_packets_buffer_init(&isight->buffer, isight->unit,
+				       QUEUE_LENGTH,
+				       sizeof(struct audio_payload),
+				       DMA_FROM_DEVICE);
+}
+
+static int isight_close(struct snd_pcm_substream *substream)
+{
+	struct isight *isight = substream->private_data;
+
+	iso_packets_buffer_destroy(&isight->buffer, isight->unit);
+
+	return 0;
+}
+
+static int isight_hw_params(struct snd_pcm_substream *substream,
+			    struct snd_pcm_hw_params *hw_params)
+{
+	struct isight *isight = substream->private_data;
+
+	WRITE_ONCE(isight->pcm_active, true);
+
+	return 0;
+}
+
+static int reg_read(struct isight *isight, int offset, __be32 *value)
+{
+	return snd_fw_transaction(isight->unit, TCODE_READ_QUADLET_REQUEST,
+				  isight->audio_base + offset, value, 4, 0);
+}
+
+static int reg_write(struct isight *isight, int offset, __be32 value)
+{
+	return snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
+				  isight->audio_base + offset, &value, 4, 0);
+}
+
+static void isight_stop_streaming(struct isight *isight)
+{
+	__be32 value;
+
+	if (!isight->context)
+		return;
+
+	fw_iso_context_stop(isight->context);
+	fw_iso_context_destroy(isight->context);
+	isight->context = NULL;
+	fw_iso_resources_free(&isight->resources);
+	value = 0;
+	snd_fw_transaction(isight->unit, TCODE_WRITE_QUADLET_REQUEST,
+			   isight->audio_base + REG_AUDIO_ENABLE,
+			   &value, 4, FW_QUIET);
+}
+
+static int isight_hw_free(struct snd_pcm_substream *substream)
+{
+	struct isight *isight = substream->private_data;
+
+	WRITE_ONCE(isight->pcm_active, false);
+
+	mutex_lock(&isight->mutex);
+	isight_stop_streaming(isight);
+	mutex_unlock(&isight->mutex);
+
+	return 0;
+}
+
+static int isight_start_streaming(struct isight *isight)
+{
+	unsigned int i;
+	int err;
+
+	if (isight->context) {
+		if (isight->packet_index < 0)
+			isight_stop_streaming(isight);
+		else
+			return 0;
+	}
+
+	err = reg_write(isight, REG_SAMPLE_RATE, cpu_to_be32(RATE_48000));
+	if (err < 0)
+		goto error;
+
+	err = isight_connect(isight);
+	if (err < 0)
+		goto error;
+
+	err = reg_write(isight, REG_AUDIO_ENABLE, cpu_to_be32(AUDIO_ENABLE));
+	if (err < 0)
+		goto err_resources;
+
+	isight->context = fw_iso_context_create(isight->device->card,
+						FW_ISO_CONTEXT_RECEIVE,
+						isight->resources.channel,
+						isight->device->max_speed,
+						4, isight_packet, isight);
+	if (IS_ERR(isight->context)) {
+		err = PTR_ERR(isight->context);
+		isight->context = NULL;
+		goto err_resources;
+	}
+
+	for (i = 0; i < QUEUE_LENGTH; ++i) {
+		err = fw_iso_context_queue(isight->context, &audio_packet,
+					   &isight->buffer.iso_buffer,
+					   isight->buffer.packets[i].offset);
+		if (err < 0)
+			goto err_context;
+	}
+
+	isight->first_packet = true;
+	isight->packet_index = 0;
+
+	err = fw_iso_context_start(isight->context, -1, 0,
+				   FW_ISO_CONTEXT_MATCH_ALL_TAGS/*?*/);
+	if (err < 0)
+		goto err_context;
+
+	return 0;
+
+err_context:
+	fw_iso_context_destroy(isight->context);
+	isight->context = NULL;
+err_resources:
+	fw_iso_resources_free(&isight->resources);
+	reg_write(isight, REG_AUDIO_ENABLE, 0);
+error:
+	return err;
+}
+
+static int isight_prepare(struct snd_pcm_substream *substream)
+{
+	struct isight *isight = substream->private_data;
+	int err;
+
+	isight->buffer_pointer = 0;
+	isight->period_counter = 0;
+
+	mutex_lock(&isight->mutex);
+	err = isight_start_streaming(isight);
+	mutex_unlock(&isight->mutex);
+
+	return err;
+}
+
+static int isight_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct isight *isight = substream->private_data;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		WRITE_ONCE(isight->pcm_running, true);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		WRITE_ONCE(isight->pcm_running, false);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static snd_pcm_uframes_t isight_pointer(struct snd_pcm_substream *substream)
+{
+	struct isight *isight = substream->private_data;
+
+	return READ_ONCE(isight->buffer_pointer);
+}
+
+static int isight_create_pcm(struct isight *isight)
+{
+	static const struct snd_pcm_ops ops = {
+		.open      = isight_open,
+		.close     = isight_close,
+		.hw_params = isight_hw_params,
+		.hw_free   = isight_hw_free,
+		.prepare   = isight_prepare,
+		.trigger   = isight_trigger,
+		.pointer   = isight_pointer,
+	};
+	struct snd_pcm *pcm;
+	int err;
+
+	err = snd_pcm_new(isight->card, "iSight", 0, 0, 1, &pcm);
+	if (err < 0)
+		return err;
+	pcm->private_data = isight;
+	strcpy(pcm->name, "iSight");
+	isight->pcm = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
+	isight->pcm->ops = &ops;
+	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC, NULL, 0, 0);
+
+	return 0;
+}
+
+static int isight_gain_info(struct snd_kcontrol *ctl,
+			    struct snd_ctl_elem_info *info)
+{
+	struct isight *isight = ctl->private_data;
+
+	info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+	info->count = 1;
+	info->value.integer.min = isight->gain_min;
+	info->value.integer.max = isight->gain_max;
+
+	return 0;
+}
+
+static int isight_gain_get(struct snd_kcontrol *ctl,
+			   struct snd_ctl_elem_value *value)
+{
+	struct isight *isight = ctl->private_data;
+	__be32 gain;
+	int err;
+
+	err = reg_read(isight, REG_GAIN, &gain);
+	if (err < 0)
+		return err;
+
+	value->value.integer.value[0] = (s32)be32_to_cpu(gain);
+
+	return 0;
+}
+
+static int isight_gain_put(struct snd_kcontrol *ctl,
+			   struct snd_ctl_elem_value *value)
+{
+	struct isight *isight = ctl->private_data;
+
+	if (value->value.integer.value[0] < isight->gain_min ||
+	    value->value.integer.value[0] > isight->gain_max)
+		return -EINVAL;
+
+	return reg_write(isight, REG_GAIN,
+			 cpu_to_be32(value->value.integer.value[0]));
+}
+
+static int isight_mute_get(struct snd_kcontrol *ctl,
+			   struct snd_ctl_elem_value *value)
+{
+	struct isight *isight = ctl->private_data;
+	__be32 mute;
+	int err;
+
+	err = reg_read(isight, REG_MUTE, &mute);
+	if (err < 0)
+		return err;
+
+	value->value.integer.value[0] = !mute;
+
+	return 0;
+}
+
+static int isight_mute_put(struct snd_kcontrol *ctl,
+			   struct snd_ctl_elem_value *value)
+{
+	struct isight *isight = ctl->private_data;
+
+	return reg_write(isight, REG_MUTE,
+			 (__force __be32)!value->value.integer.value[0]);
+}
+
+static int isight_create_mixer(struct isight *isight)
+{
+	static const struct snd_kcontrol_new gain_control = {
+		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+		.name = "Mic Capture Volume",
+		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
+			  SNDRV_CTL_ELEM_ACCESS_TLV_READ,
+		.info = isight_gain_info,
+		.get = isight_gain_get,
+		.put = isight_gain_put,
+	};
+	static const struct snd_kcontrol_new mute_control = {
+		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+		.name = "Mic Capture Switch",
+		.info = snd_ctl_boolean_mono_info,
+		.get = isight_mute_get,
+		.put = isight_mute_put,
+	};
+	__be32 value;
+	struct snd_kcontrol *ctl;
+	int err;
+
+	err = reg_read(isight, REG_GAIN_RAW_START, &value);
+	if (err < 0)
+		return err;
+	isight->gain_min = be32_to_cpu(value);
+
+	err = reg_read(isight, REG_GAIN_RAW_END, &value);
+	if (err < 0)
+		return err;
+	isight->gain_max = be32_to_cpu(value);
+
+	isight->gain_tlv[SNDRV_CTL_TLVO_TYPE] = SNDRV_CTL_TLVT_DB_MINMAX;
+	isight->gain_tlv[SNDRV_CTL_TLVO_LEN] = 2 * sizeof(unsigned int);
+
+	err = reg_read(isight, REG_GAIN_DB_START, &value);
+	if (err < 0)
+		return err;
+	isight->gain_tlv[SNDRV_CTL_TLVO_DB_MINMAX_MIN] =
+						(s32)be32_to_cpu(value) * 100;
+
+	err = reg_read(isight, REG_GAIN_DB_END, &value);
+	if (err < 0)
+		return err;
+	isight->gain_tlv[SNDRV_CTL_TLVO_DB_MINMAX_MAX] =
+						(s32)be32_to_cpu(value) * 100;
+
+	ctl = snd_ctl_new1(&gain_control, isight);
+	if (ctl)
+		ctl->tlv.p = isight->gain_tlv;
+	err = snd_ctl_add(isight->card, ctl);
+	if (err < 0)
+		return err;
+
+	err = snd_ctl_add(isight->card, snd_ctl_new1(&mute_control, isight));
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+static void isight_card_free(struct snd_card *card)
+{
+	struct isight *isight = card->private_data;
+
+	fw_iso_resources_destroy(&isight->resources);
+}
+
+static u64 get_unit_base(struct fw_unit *unit)
+{
+	struct fw_csr_iterator i;
+	int key, value;
+
+	fw_csr_iterator_init(&i, unit->directory);
+	while (fw_csr_iterator_next(&i, &key, &value))
+		if (key == CSR_OFFSET)
+			return CSR_REGISTER_BASE + value * 4;
+	return 0;
+}
+
+static int isight_probe(struct fw_unit *unit,
+			const struct ieee1394_device_id *id)
+{
+	struct fw_device *fw_dev = fw_parent_device(unit);
+	struct snd_card *card;
+	struct isight *isight;
+	int err;
+
+	err = snd_card_new(&unit->device, -1, NULL, THIS_MODULE,
+			   sizeof(*isight), &card);
+	if (err < 0)
+		return err;
+
+	isight = card->private_data;
+	isight->card = card;
+	mutex_init(&isight->mutex);
+	isight->unit = fw_unit_get(unit);
+	isight->device = fw_dev;
+	isight->audio_base = get_unit_base(unit);
+	if (!isight->audio_base) {
+		dev_err(&unit->device, "audio unit base not found\n");
+		err = -ENXIO;
+		goto error;
+	}
+	fw_iso_resources_init(&isight->resources, unit);
+
+	card->private_free = isight_card_free;
+
+	strcpy(card->driver, "iSight");
+	strcpy(card->shortname, "Apple iSight");
+	snprintf(card->longname, sizeof(card->longname),
+		 "Apple iSight (GUID %08x%08x) at %s, S%d",
+		 fw_dev->config_rom[3], fw_dev->config_rom[4],
+		 dev_name(&unit->device), 100 << fw_dev->max_speed);
+	strcpy(card->mixername, "iSight");
+
+	err = isight_create_pcm(isight);
+	if (err < 0)
+		goto error;
+
+	err = isight_create_mixer(isight);
+	if (err < 0)
+		goto error;
+
+	err = snd_card_register(card);
+	if (err < 0)
+		goto error;
+
+	dev_set_drvdata(&unit->device, isight);
+
+	return 0;
+error:
+	snd_card_free(card);
+
+	mutex_destroy(&isight->mutex);
+	fw_unit_put(isight->unit);
+
+	return err;
+}
+
+static void isight_bus_reset(struct fw_unit *unit)
+{
+	struct isight *isight = dev_get_drvdata(&unit->device);
+
+	if (fw_iso_resources_update(&isight->resources) < 0) {
+		isight_pcm_abort(isight);
+
+		mutex_lock(&isight->mutex);
+		isight_stop_streaming(isight);
+		mutex_unlock(&isight->mutex);
+	}
+}
+
+static void isight_remove(struct fw_unit *unit)
+{
+	struct isight *isight = dev_get_drvdata(&unit->device);
+
+	isight_pcm_abort(isight);
+
+	snd_card_disconnect(isight->card);
+
+	mutex_lock(&isight->mutex);
+	isight_stop_streaming(isight);
+	mutex_unlock(&isight->mutex);
+
+	// Block till all of ALSA character devices are released.
+	snd_card_free(isight->card);
+
+	mutex_destroy(&isight->mutex);
+	fw_unit_put(isight->unit);
+}
+
+static const struct ieee1394_device_id isight_id_table[] = {
+	{
+		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
+				IEEE1394_MATCH_VERSION,
+		.specifier_id = OUI_APPLE,
+		.version      = SW_ISIGHT_AUDIO,
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(ieee1394, isight_id_table);
+
+static struct fw_driver isight_driver = {
+	.driver   = {
+		.owner	= THIS_MODULE,
+		.name	= KBUILD_MODNAME,
+		.bus	= &fw_bus_type,
+	},
+	.probe    = isight_probe,
+	.update   = isight_bus_reset,
+	.remove   = isight_remove,
+	.id_table = isight_id_table,
+};
+
+static int __init alsa_isight_init(void)
+{
+	return driver_register(&isight_driver.driver);
+}
+
+static void __exit alsa_isight_exit(void)
+{
+	driver_unregister(&isight_driver.driver);
+}
+
+module_init(alsa_isight_init);
+module_exit(alsa_isight_exit);