ALSA: add DICE driver

As a start point for further development, this is an incomplete driver
for DICE devices:
- only playback (so no clock source except the bus clock)
- only 44.1 kHz
- no MIDI
- recovery after bus reset is slow
- hwdep device is created, but not actually implemented

Contains compilation fixes by Stefan Richter.

Signed-off-by: Clemens Ladisch <[e-mail]>

Documentation/ioctl/ioctl-number.txt

···
 'H'	C0-DF	net/bluetooth/cmtp/cmtp.h	conflict!
 'H'	C0-DF	net/bluetooth/bnep/bnep.h	conflict!
 'H'	F1	linux/hid-roccat.h	<mailto:[e-mail]>
+'H'	F8-FA	sound/firewire.h
 'I'	all	linux/isdn.h		conflict!
 'I'	00-0F	drivers/isdn/divert/isdn_divert.h	conflict!
 'I'	40-4F	linux/mISDNif.h		conflict!

include/uapi/sound/Kbuild

···
 header-y += compress_offload.h
 header-y += compress_params.h
 header-y += emu10k1.h
+header-y += firewire.h
 header-y += hdsp.h
 header-y += hdspm.h
 header-y += sb16_csp.h

include/uapi/sound/asound.h

···
 	SNDRV_HWDEP_IFACE_SB_RC,	/* SB Extigy/Audigy2NX remote control */
 	SNDRV_HWDEP_IFACE_HDA,		/* HD-audio */
 	SNDRV_HWDEP_IFACE_USB_STREAM,	/* direct access to usb stream */
+	SNDRV_HWDEP_IFACE_FW_DICE,	/* TC DICE FireWire device */
 
 	/* Don't forget to change the following: */
-	SNDRV_HWDEP_IFACE_LAST = SNDRV_HWDEP_IFACE_USB_STREAM
+	SNDRV_HWDEP_IFACE_LAST = SNDRV_HWDEP_IFACE_FW_DICE
 };
 
 struct snd_hwdep_info {

include/uapi/sound/firewire.h

···
+#ifndef UAPI_SOUND_FIREWIRE_H_INCLUDED
+#define UAPI_SOUND_FIREWIRE_H_INCLUDED
+
+#include <linux/ioctl.h>
+
+/* events can be read() from the hwdep device */
+
+#define SNDRV_FIREWIRE_EVENT_LOCK_STATUS	0x000010cc
+#define SNDRV_FIREWIRE_EVENT_DICE_NOTIFICATION	0xd1ce004e
+
+struct snd_firewire_event_common {
+	unsigned int type; /* SNDRV_FIREWIRE_EVENT_xxx */
+};
+
+struct snd_firewire_event_lock_status {
+	unsigned int type;
+	unsigned int status; /* 0/1 = unlocked/locked */
+};
+
+struct snd_firewire_event_dice_notification {
+	unsigned int type;
+	unsigned int notification; /* DICE-specific bits */
+};
+
+union snd_firewire_event {
+	struct snd_firewire_event_common            common;
+	struct snd_firewire_event_lock_status       lock_status;
+	struct snd_firewire_event_dice_notification dice_notification;
+};
+
+
+#define SNDRV_FIREWIRE_IOCTL_GET_INFO _IOR('H', 0xf8, struct snd_firewire_get_info)
+#define SNDRV_FIREWIRE_IOCTL_LOCK      _IO('H', 0xf9)
+#define SNDRV_FIREWIRE_IOCTL_UNLOCK    _IO('H', 0xfa)
+
+#define SNDRV_FIREWIRE_TYPE_DICE	1
+/* Fireworks, AV/C, RME, MOTU, ... */
+
+struct snd_firewire_get_info {
+	unsigned int type; /* SNDRV_FIREWIRE_TYPE_xxx */
+	unsigned int card; /* same as fw_cdev_get_info.card */
+	unsigned char guid[8];
+	char device_name[16]; /* device node in /dev */
+};
+
+/*
+ * SNDRV_FIREWIRE_IOCTL_LOCK prevents the driver from streaming.
+ * Returns -EBUSY if the driver is already streaming.
+ */
+
+#endif

sound/firewire/Kconfig

···
 	tristate
 	depends on SND_PCM
 
+config SND_DICE
+	tristate "DICE devices (EXPERIMENTAL)"
+	select SND_HWDEP
+	select SND_PCM
+	select SND_FIREWIRE_LIB
+	help
+	  Say Y here to include support for many FireWire audio interfaces
+	  based on the DICE chip family (DICE-II/Jr/Mini) from TC Applied
+	  Technologies.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-dice.
+
 config SND_FIREWIRE_SPEAKERS
 	tristate "FireWire speakers"
 	select SND_PCM

sound/firewire/Makefile

···
 snd-firewire-lib-objs := lib.o iso-resources.o packets-buffer.o \
 			 fcp.o cmp.o amdtp.o
+snd-dice-objs := dice.o
 snd-firewire-speakers-objs := speakers.o
 snd-isight-objs := isight.o
 snd-scs1x-objs := scs1x.o
 
 obj-$(CONFIG_SND_FIREWIRE_LIB) += snd-firewire-lib.o
+obj-$(CONFIG_SND_DICE) += snd-dice.o
 obj-$(CONFIG_SND_FIREWIRE_SPEAKERS) += snd-firewire-speakers.o
 obj-$(CONFIG_SND_ISIGHT) += snd-isight.o
 obj-$(CONFIG_SND_SCS1X) += snd-scs1x.o

sound/firewire/dice.c

···
+/*
+ * TC Applied Technologies Digital Interface Communications Engine driver
+ *
+ * Copyright (c) Clemens Ladisch <[e-mail]>
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+
+#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/slab.h>
+#include <sound/control.h>
+#include <sound/core.h>
+#include <sound/hwdep.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include "amdtp.h"
+#include "iso-resources.h"
+#include "lib.h"
+
+#define DICE_PRIVATE_SPACE		0xffffe0000000uLL
+
+/* offset from DICE_PRIVATE_SPACE; offsets and sizes in quadlets */
+#define DICE_GLOBAL_OFFSET		0x00
+#define DICE_GLOBAL_SIZE		0x04
+#define DICE_TX_OFFSET			0x08
+#define DICE_TX_SIZE			0x0c
+#define DICE_RX_OFFSET			0x10
+#define DICE_RX_SIZE			0x14
+
+/* pointed to by DICE_GLOBAL_OFFSET */
+#define GLOBAL_OWNER			0x000
+#define  OWNER_NO_OWNER			0xffff000000000000uLL
+#define  OWNER_NODE_SHIFT		48
+#define GLOBAL_NOTIFICATION		0x008
+#define  NOTIFY_RX_CFG_CHG		0x00000001
+#define  NOTIFY_TX_CFG_CHG		0x00000002
+#define  NOTIFY_DUP_ISOC		0x00000004
+#define  NOTIFY_BW_ERR			0x00000008
+#define  NOTIFY_LOCK_CHG		0x00000010
+#define  NOTIFY_CLOCK_ACCEPTED		0x00000020
+#define  NOTIFY_INTERFACE_CHG		0x00000040
+#define  NOTIFY_MESSAGE			0x00100000
+#define GLOBAL_NICK_NAME		0x00c
+#define  NICK_NAME_SIZE			64
+#define GLOBAL_CLOCK_SELECT		0x04c
+#define  CLOCK_SOURCE_MASK		0x000000ff
+#define  CLOCK_SOURCE_AES1		0x00000000
+#define  CLOCK_SOURCE_AES2		0x00000001
+#define  CLOCK_SOURCE_AES3		0x00000002
+#define  CLOCK_SOURCE_AES4		0x00000003
+#define  CLOCK_SOURCE_AES_ANY		0x00000004
+#define  CLOCK_SOURCE_ADAT		0x00000005
+#define  CLOCK_SOURCE_TDIF		0x00000006
+#define  CLOCK_SOURCE_WC		0x00000007
+#define  CLOCK_SOURCE_ARX1		0x00000008
+#define  CLOCK_SOURCE_ARX2		0x00000009
+#define  CLOCK_SOURCE_ARX3		0x0000000a
+#define  CLOCK_SOURCE_ARX4		0x0000000b
+#define  CLOCK_SOURCE_INTERNAL		0x0000000c
+#define  CLOCK_RATE_MASK		0x0000ff00
+#define  CLOCK_RATE_32000		0x00000000
+#define  CLOCK_RATE_44100		0x00000100
+#define  CLOCK_RATE_48000		0x00000200
+#define  CLOCK_RATE_88200		0x00000300
+#define  CLOCK_RATE_96000		0x00000400
+#define  CLOCK_RATE_176400		0x00000500
+#define  CLOCK_RATE_192000		0x00000600
+#define  CLOCK_RATE_ANY_LOW		0x00000700
+#define  CLOCK_RATE_ANY_MID		0x00000800
+#define  CLOCK_RATE_ANY_HIGH		0x00000900
+#define  CLOCK_RATE_NONE		0x00000a00
+#define GLOBAL_ENABLE			0x050
+#define  ENABLE				0x00000001
+#define GLOBAL_STATUS			0x054
+#define  STATUS_SOURCE_LOCKED		0x00000001
+#define  STATUS_RATE_CONFLICT		0x00000002
+#define  STATUS_NOMINAL_RATE_MASK	0x0000ff00
+#define GLOBAL_EXTENDED_STATUS		0x058
+#define  EXT_STATUS_AES1_LOCKED		0x00000001
+#define  EXT_STATUS_AES2_LOCKED		0x00000002
+#define  EXT_STATUS_AES3_LOCKED		0x00000004
+#define  EXT_STATUS_AES4_LOCKED		0x00000008
+#define  EXT_STATUS_ADAT_LOCKED		0x00000010
+#define  EXT_STATUS_TDIF_LOCKED		0x00000020
+#define  EXT_STATUS_ARX1_LOCKED		0x00000040
+#define  EXT_STATUS_ARX2_LOCKED		0x00000080
+#define  EXT_STATUS_ARX3_LOCKED		0x00000100
+#define  EXT_STATUS_ARX4_LOCKED		0x00000200
+#define  EXT_STATUS_WC_LOCKED		0x00000400
+#define  EXT_STATUS_AES1_SLIP		0x00010000
+#define  EXT_STATUS_AES2_SLIP		0x00020000
+#define  EXT_STATUS_AES3_SLIP		0x00040000
+#define  EXT_STATUS_AES4_SLIP		0x00080000
+#define  EXT_STATUS_ADAT_SLIP		0x00100000
+#define  EXT_STATUS_TDIF_SLIP		0x00200000
+#define  EXT_STATUS_ARX1_SLIP		0x00400000
+#define  EXT_STATUS_ARX2_SLIP		0x00800000
+#define  EXT_STATUS_ARX3_SLIP		0x01000000
+#define  EXT_STATUS_ARX4_SLIP		0x02000000
+#define  EXT_STATUS_WC_SLIP		0x04000000
+#define GLOBAL_SAMPLE_RATE		0x05c
+#define GLOBAL_VERSION			0x060
+#define GLOBAL_CLOCK_CAPABILITIES	0x064
+#define  CLOCK_CAP_RATE_32000		0x00000001
+#define  CLOCK_CAP_RATE_44100		0x00000002
+#define  CLOCK_CAP_RATE_48000		0x00000004
+#define  CLOCK_CAP_RATE_88200		0x00000008
+#define  CLOCK_CAP_RATE_96000		0x00000010
+#define  CLOCK_CAP_RATE_176400		0x00000020
+#define  CLOCK_CAP_RATE_192000		0x00000040
+#define  CLOCK_CAP_SOURCE_AES1		0x00010000
+#define  CLOCK_CAP_SOURCE_AES2		0x00020000
+#define  CLOCK_CAP_SOURCE_AES3		0x00040000
+#define  CLOCK_CAP_SOURCE_AES4		0x00080000
+#define  CLOCK_CAP_SOURCE_AES_ANY	0x00100000
+#define  CLOCK_CAP_SOURCE_ADAT		0x00200000
+#define  CLOCK_CAP_SOURCE_TDIF		0x00400000
+#define  CLOCK_CAP_SOURCE_WC		0x00800000
+#define  CLOCK_CAP_SOURCE_ARX1		0x01000000
+#define  CLOCK_CAP_SOURCE_ARX2		0x02000000
+#define  CLOCK_CAP_SOURCE_ARX3		0x04000000
+#define  CLOCK_CAP_SOURCE_ARX4		0x08000000
+#define  CLOCK_CAP_SOURCE_INTERNAL	0x10000000
+#define GLOBAL_CLOCK_SOURCE_NAMES	0x068
+#define  CLOCK_SOURCE_NAMES_SIZE	256
+
+/* pointed to by DICE_TX_OFFSET */
+#define TX_NUMBER			0x000
+#define TX_SIZE				0x004
+/* repeated TX_NUMBER times, offset by TX_SIZE quadlets */
+#define TX_ISOCHRONOUS			0x008
+#define TX_NUMBER_AUDIO			0x00c
+#define TX_NUMBER_MIDI			0x010
+#define TX_SPEED			0x014
+#define TX_NAMES			0x018
+#define  TX_NAMES_SIZE			256
+#define TX_AC3_CAPABILITIES		0x118
+#define TX_AC3_ENABLE			0x11c
+
+/* pointed to by DICE_RX_OFFSET */
+#define RX_NUMBER			0x000
+#define RX_SIZE				0x004
+/* repeated RX_NUMBER times, offset by RX_SIZE quadlets */
+#define RX_ISOCHRONOUS			0x008
+#define RX_SEQ_START			0x00c
+#define RX_NUMBER_AUDIO			0x010
+#define RX_NUMBER_MIDI			0x014
+#define RX_NAMES			0x018
+#define  RX_NAMES_SIZE			256
+#define RX_AC3_CAPABILITIES		0x118
+#define RX_AC3_ENABLE			0x11c
+
+
+#define FIRMWARE_LOAD_SPACE		0xffffe0100000uLL
+
+/* offset from FIRMWARE_LOAD_SPACE */
+#define FIRMWARE_VERSION		0x000
+#define FIRMWARE_OPCODE			0x004
+#define  OPCODE_MASK			0x00000fff
+#define  OPCODE_GET_IMAGE_DESC		0x00000000
+#define  OPCODE_DELETE_IMAGE		0x00000001
+#define  OPCODE_CREATE_IMAGE		0x00000002
+#define  OPCODE_UPLOAD			0x00000003
+#define  OPCODE_UPLOAD_STAT		0x00000004
+#define  OPCODE_RESET_IMAGE		0x00000005
+#define  OPCODE_TEST_ACTION		0x00000006
+#define  OPCODE_GET_RUNNING_IMAGE_VINFO	0x0000000a
+#define  OPCODE_EXECUTE			0x80000000
+#define FIRMWARE_RETURN_STATUS		0x008
+#define FIRMWARE_PROGRESS		0x00c
+#define  PROGRESS_CURR_MASK		0x00000fff
+#define  PROGRESS_MAX_MASK		0x00fff000
+#define  PROGRESS_TOUT_MASK		0x0f000000
+#define  PROGRESS_FLAG			0x80000000
+#define FIRMWARE_CAPABILITIES		0x010
+#define  FL_CAP_AUTOERASE		0x00000001
+#define  FL_CAP_PROGRESS		0x00000002
+#define FIRMWARE_DATA			0x02c
+#define  TEST_CMD_POKE			0x00000001
+#define  TEST_CMD_PEEK			0x00000002
+#define  CMD_GET_AVS_CNT		0x00000003
+#define  CMD_CLR_AVS_CNT		0x00000004
+#define  CMD_SET_MODE			0x00000005
+#define  CMD_SET_MIDIBP			0x00000006
+#define  CMD_GET_AVSPHASE		0x00000007
+#define  CMD_ENABLE_BNC_SYNC		0x00000008
+#define  CMD_PULSE_BNC_SYNC		0x00000009
+#define  CMD_EMUL_SLOW_CMD		0x0000000a
+#define FIRMWARE_TEST_DELAY		0xfd8
+#define FIRMWARE_TEST_BUF		0xfdc
+
+
+/* EAP */
+#define EAP_PRIVATE_SPACE		0xffffe0200000uLL
+
+#define EAP_CAPABILITY_OFFSET		0x000
+#define EAP_CAPABILITY_SIZE		0x004
+/* ... */
+
+#define EAP_ROUTER_CAPS			0x000
+#define  ROUTER_EXPOSED			0x00000001
+#define  ROUTER_READ_ONLY		0x00000002
+#define  ROUTER_FLASH			0x00000004
+#define  MAX_ROUTES_MASK		0xffff0000
+#define EAP_MIXER_CAPS			0x004
+#define  MIXER_EXPOSED			0x00000001
+#define  MIXER_READ_ONLY		0x00000002
+#define  MIXER_FLASH			0x00000004
+#define  MIXER_IN_DEV_MASK		0x000000f0
+#define  MIXER_OUT_DEV_MASK		0x00000f00
+#define  MIXER_INPUTS_MASK		0x00ff0000
+#define  MIXER_OUTPUTS_MASK		0xff000000
+#define EAP_GENERAL_CAPS		0x008
+#define  GENERAL_STREAM_CONFIG		0x00000001
+#define  GENERAL_FLASH			0x00000002
+#define  GENERAL_PEAK			0x00000004
+#define  GENERAL_MAX_TX_STREAMS_MASK	0x000000f0
+#define  GENERAL_MAX_RX_STREAMS_MASK	0x00000f00
+#define  GENERAL_STREAM_CONFIG_FLASH	0x00001000
+#define  GENERAL_CHIP_MASK		0x00ff0000
+#define  GENERAL_CHIP_DICE_II		0x00000000
+#define  GENERAL_CHIP_DICE_MINI		0x00010000
+#define  GENERAL_CHIP_DICE_JR		0x00020000
+
+
+struct dice {
+	struct snd_card *card;
+	struct fw_unit *unit;
+	struct mutex mutex;
+	unsigned int global_offset;
+	unsigned int rx_offset;
+	struct fw_address_handler notification_handler;
+	int owner_generation;
+	bool global_enabled;
+	bool stream_running;
+	struct snd_pcm_substream *pcm;
+	struct fw_iso_resources resources;
+	struct amdtp_out_stream stream;
+};
+
+MODULE_DESCRIPTION("DICE driver");
+MODULE_AUTHOR("Clemens Ladisch <[e-mail]>");
+MODULE_LICENSE("GPL v2");
+
+static inline u64 global_address(struct dice *dice, unsigned int offset)
+{
+	return DICE_PRIVATE_SPACE + dice->global_offset + offset;
+}
+
+// TODO: rx index
+static inline u64 rx_address(struct dice *dice, unsigned int offset)
+{
+	return DICE_PRIVATE_SPACE + dice->rx_offset + offset;
+}
+
+static int dice_owner_set(struct dice *dice)
+{
+	struct fw_device *device = fw_parent_device(dice->unit);
+	__be64 *buffer;
+	int rcode, err, errors = 0;
+
+	buffer = kmalloc(2 * 8, GFP_KERNEL);
+	if (!buffer)
+		return -ENOMEM;
+
+	for (;;) {
+		buffer[0] = cpu_to_be64(OWNER_NO_OWNER);
+		buffer[1] = cpu_to_be64(
+			((u64)device->card->node_id << OWNER_NODE_SHIFT) |
+			dice->notification_handler.offset);
+
+		dice->owner_generation = device->generation;
+		smp_rmb(); /* node_id vs. generation */
+		rcode = fw_run_transaction(device->card,
+					   TCODE_LOCK_COMPARE_SWAP,
+					   device->node_id,
+					   dice->owner_generation,
+					   device->max_speed,
+					   global_address(dice, GLOBAL_OWNER),
+					   buffer, 2 * 8);
+
+		if (rcode == RCODE_COMPLETE) {
+			if (buffer[0] == cpu_to_be64(OWNER_NO_OWNER)) {
+				err = 0;
+			} else {
+				dev_err(&dice->unit->device,
+					"device is already in use\n");
+				err = -EBUSY;
+			}
+			break;
+		}
+		if (rcode_is_permanent_error(rcode) || ++errors >= 3) {
+			dev_err(&dice->unit->device,
+				"setting device owner failed: %s\n",
+				fw_rcode_string(rcode));
+			err = -EIO;
+			break;
+		}
+		msleep(20);
+	}
+
+	kfree(buffer);
+
+	return err;
+}
+
+static int dice_owner_update(struct dice *dice)
+{
+	struct fw_device *device = fw_parent_device(dice->unit);
+	__be64 *buffer;
+	int rcode, err, errors = 0;
+
+	if (dice->owner_generation == -1)
+		return 0;
+
+	buffer = kmalloc(2 * 8, GFP_KERNEL);
+	if (!buffer)
+		return -ENOMEM;
+
+	for (;;) {
+		buffer[0] = cpu_to_be64(OWNER_NO_OWNER);
+		buffer[1] = cpu_to_be64(
+			((u64)device->card->node_id << OWNER_NODE_SHIFT) |
+			dice->notification_handler.offset);
+
+		dice->owner_generation = device->generation;
+		smp_rmb(); /* node_id vs. generation */
+		rcode = fw_run_transaction(device->card,
+					   TCODE_LOCK_COMPARE_SWAP,
+					   device->node_id,
+					   dice->owner_generation,
+					   device->max_speed,
+					   global_address(dice, GLOBAL_OWNER),
+					   buffer, 2 * 8);
+
+		if (rcode == RCODE_COMPLETE) {
+			if (buffer[0] == cpu_to_be64(OWNER_NO_OWNER)) {
+				err = 0;
+			} else {
+				dev_err(&dice->unit->device,
+					"device is already in use\n");
+				err = -EBUSY;
+			}
+			break;
+		}
+		if (rcode == RCODE_GENERATION) {
+			err = 0; /* try again later */
+			break;
+		}
+		if (rcode_is_permanent_error(rcode) || ++errors >= 3) {
+			dev_err(&dice->unit->device,
+				"setting device owner failed: %s\n",
+				fw_rcode_string(rcode));
+			err = -EIO;
+			break;
+		}
+		msleep(20);
+	}
+
+	kfree(buffer);
+
+	if (err < 0)
+		dice->owner_generation = -1;
+
+	return err;
+}
+
+static void dice_owner_clear(struct dice *dice)
+{
+	struct fw_device *device = fw_parent_device(dice->unit);
+	__be64 *buffer;
+	int rcode, errors = 0;
+
+	buffer = kmalloc(2 * 8, GFP_KERNEL);
+	if (!buffer)
+		return;
+
+	for (;;) {
+		buffer[0] = cpu_to_be64(
+			((u64)device->card->node_id << OWNER_NODE_SHIFT) |
+			dice->notification_handler.offset);
+		buffer[1] = cpu_to_be64(OWNER_NO_OWNER);
+
+		rcode = fw_run_transaction(device->card,
+					   TCODE_LOCK_COMPARE_SWAP,
+					   device->node_id,
+					   dice->owner_generation,
+					   device->max_speed,
+					   global_address(dice, GLOBAL_OWNER),
+					   buffer, 2 * 8);
+
+		if (rcode == RCODE_COMPLETE)
+			break;
+		if (rcode == RCODE_GENERATION)
+			break;
+		if (rcode_is_permanent_error(rcode) || ++errors >= 3) {
+			dev_err(&dice->unit->device,
+				"clearing device owner failed: %s\n",
+				fw_rcode_string(rcode));
+			break;
+		}
+		msleep(20);
+	}
+
+	kfree(buffer);
+
+	dice->owner_generation = -1;
+}
+
+static int dice_enable_set(struct dice *dice)
+{
+	struct fw_device *device = fw_parent_device(dice->unit);
+	__be32 value;
+	int rcode, err, errors = 0;
+
+	value = cpu_to_be32(ENABLE);
+	for (;;) {
+		rcode = fw_run_transaction(device->card,
+					   TCODE_WRITE_QUADLET_REQUEST,
+					   device->node_id,
+					   dice->owner_generation,
+					   device->max_speed,
+					   global_address(dice, GLOBAL_ENABLE),
+					   &value, 4);
+		if (rcode == RCODE_COMPLETE) {
+			dice->global_enabled = true;
+			err = 0;
+			break;
+		}
+		if (rcode == RCODE_GENERATION) {
+			err = -EAGAIN;
+			break;
+		}
+		if (rcode_is_permanent_error(rcode) || ++errors >= 3) {
+			dev_err(&dice->unit->device,
+				"device enabling failed: %s\n",
+				fw_rcode_string(rcode));
+			err = -EIO;
+			break;
+		}
+		msleep(20);
+	}
+
+	return err;
+}
+
+static void dice_enable_clear(struct dice *dice)
+{
+	struct fw_device *device = fw_parent_device(dice->unit);
+	__be32 value;
+	int rcode, errors = 0;
+
+	value = 0;
+	for (;;) {
+		rcode = fw_run_transaction(device->card,
+					   TCODE_WRITE_QUADLET_REQUEST,
+					   device->node_id,
+					   dice->owner_generation,
+					   device->max_speed,
+					   global_address(dice, GLOBAL_ENABLE),
+					   &value, 4);
+		if (rcode == RCODE_COMPLETE ||
+		    rcode == RCODE_GENERATION)
+			break;
+		if (rcode_is_permanent_error(rcode) || ++errors >= 3) {
+			dev_err(&dice->unit->device,
+				"device disabling failed: %s\n",
+				fw_rcode_string(rcode));
+			break;
+		}
+		msleep(20);
+	}
+	dice->global_enabled = false;
+}
+
+static void dice_notification(struct fw_card *card, struct fw_request *request,
+			      int tcode, int destination, int source,
+			      int generation, unsigned long long offset,
+			      void *data, size_t length, void *callback_data)
+{
+	struct dice *dice = callback_data;
+
+	if (tcode != TCODE_WRITE_QUADLET_REQUEST) {
+		fw_send_response(card, request, RCODE_TYPE_ERROR);
+		return;
+	}
+	if ((offset & 3) != 0) {
+		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
+		return;
+	}
+	dev_info(&dice->unit->device,
+		 "notification: %08x\n", be32_to_cpup(data));
+	fw_send_response(card, request, RCODE_COMPLETE);
+}
+
+static int dice_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 = AMDTP_OUT_PCM_FORMAT_BITS,
+		.rates = SNDRV_PCM_RATE_44100,
+		.rate_min = 44100,
+		.rate_max = 44100,
+		.buffer_bytes_max = 16 * 1024 * 1024,
+		.period_bytes_min = 1,
+		.period_bytes_max = UINT_MAX,
+		.periods_min = 1,
+		.periods_max = UINT_MAX,
+	};
+	struct dice *dice = substream->private_data;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	__be32 number_audio, number_midi;
+	int err;
+
+	err = snd_fw_transaction(dice->unit, TCODE_READ_QUADLET_REQUEST,
+				 rx_address(dice, RX_NUMBER_AUDIO),
+				 &number_audio, 4);
+	if (err < 0)
+		return err;
+	err = snd_fw_transaction(dice->unit, TCODE_READ_QUADLET_REQUEST,
+				 rx_address(dice, RX_NUMBER_MIDI),
+				 &number_midi, 4);
+	if (err < 0)
+		return err;
+
+	runtime->hw = hardware;
+	runtime->hw.channels_min = be32_to_cpu(number_audio);
+	runtime->hw.channels_max = be32_to_cpu(number_audio);
+
+	amdtp_out_stream_set_rate(&dice->stream, 44100);
+	amdtp_out_stream_set_pcm(&dice->stream, be32_to_cpu(number_audio));
+	amdtp_out_stream_set_midi(&dice->stream, be32_to_cpu(number_midi));
+
+	err = snd_pcm_hw_constraint_minmax(runtime,
+					   SNDRV_PCM_HW_PARAM_PERIOD_TIME,
+					   5000, 8192000);
+	if (err < 0)
+		return err;
+
+	err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+static int dice_close(struct snd_pcm_substream *substream)
+{
+	return 0;
+}
+
+static void dice_stop_stream(struct dice *dice)
+{
+	__be32 channel;
+
+	if (dice->stream_running) {
+		dice_enable_clear(dice);
+
+		amdtp_out_stream_stop(&dice->stream);
+
+		channel = cpu_to_be32((u32)-1);
+		snd_fw_transaction(dice->unit, TCODE_WRITE_QUADLET_REQUEST,
+				   rx_address(dice, RX_ISOCHRONOUS),
+				   &channel, 4);
+
+		fw_iso_resources_free(&dice->resources);
+
+		dice->stream_running = false;
+	}
+}
+
+static int dice_hw_params(struct snd_pcm_substream *substream,
+			  struct snd_pcm_hw_params *hw_params)
+{
+	struct dice *dice = substream->private_data;
+	int err;
+
+	mutex_lock(&dice->mutex);
+	dice_stop_stream(dice);
+	mutex_unlock(&dice->mutex);
+
+	err = snd_pcm_lib_alloc_vmalloc_buffer(substream,
+					       params_buffer_bytes(hw_params));
+	if (err < 0)
+		goto error;
+
+	amdtp_out_stream_set_pcm_format(&dice->stream,
+					params_format(hw_params));
+
+	return 0;
+
+error:
+	return err;
+}
+
+static int dice_hw_free(struct snd_pcm_substream *substream)
+{
+	struct dice *dice = substream->private_data;
+
+	mutex_lock(&dice->mutex);
+	dice_stop_stream(dice);
+	mutex_unlock(&dice->mutex);
+
+	return snd_pcm_lib_free_vmalloc_buffer(substream);
+}
+
+static int dice_prepare(struct snd_pcm_substream *substream)
+{
+	struct dice *dice = substream->private_data;
+	struct fw_device *device = fw_parent_device(dice->unit);
+	__be32 channel;
+	int err;
+
+	mutex_lock(&dice->mutex);
+
+	if (amdtp_out_streaming_error(&dice->stream))
+		dice_stop_stream(dice);
+
+	if (!dice->stream_running) {
+		err = fw_iso_resources_allocate(&dice->resources,
+				amdtp_out_stream_get_max_payload(&dice->stream),
+				device->max_speed);
+		if (err < 0)
+			goto error;
+
+		//TODO: RX_SEQ_START
+		channel = cpu_to_be32(dice->resources.channel);
+		err = snd_fw_transaction(dice->unit,
+					 TCODE_WRITE_QUADLET_REQUEST,
+					 rx_address(dice, RX_ISOCHRONOUS),
+					 &channel, 4);
+		if (err < 0)
+			goto err_resources;
+
+		err = amdtp_out_stream_start(&dice->stream,
+					     dice->resources.channel,
+					     device->max_speed);
+		if (err < 0)
+			goto err_resources;
+
+		err = dice_enable_set(dice);
+		if (err < 0)
+			goto err_stream;
+
+		dice->stream_running = true;
+	}
+
+	mutex_unlock(&dice->mutex);
+
+	amdtp_out_stream_pcm_prepare(&dice->stream);
+
+	return 0;
+
+err_stream:
+	amdtp_out_stream_stop(&dice->stream);
+err_resources:
+	fw_iso_resources_free(&dice->resources);
+error:
+	mutex_unlock(&dice->mutex);
+
+	return err;
+}
+
+static int dice_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct dice *dice = substream->private_data;
+	struct snd_pcm_substream *pcm;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		pcm = substream;
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		pcm = NULL;
+		break;
+	default:
+		return -EINVAL;
+	}
+	amdtp_out_stream_pcm_trigger(&dice->stream, pcm);
+
+	return 0;
+}
+
+static snd_pcm_uframes_t dice_pointer(struct snd_pcm_substream *substream)
+{
+	struct dice *dice = substream->private_data;
+
+	return amdtp_out_stream_pcm_pointer(&dice->stream);
+}
+
+static int dice_create_pcm(struct dice *dice)
+{
+	static struct snd_pcm_ops ops = {
+		.open      = dice_open,
+		.close     = dice_close,
+		.ioctl     = snd_pcm_lib_ioctl,
+		.hw_params = dice_hw_params,
+		.hw_free   = dice_hw_free,
+		.prepare   = dice_prepare,
+		.trigger   = dice_trigger,
+		.pointer   = dice_pointer,
+		.page      = snd_pcm_lib_get_vmalloc_page,
+		.mmap      = snd_pcm_lib_mmap_vmalloc,
+	};
+	__be32 clock;
+	struct snd_pcm *pcm;
+	int err;
+
+	clock = cpu_to_be32(CLOCK_SOURCE_ARX1 | CLOCK_RATE_44100);
+	err = snd_fw_transaction(dice->unit, TCODE_WRITE_QUADLET_REQUEST,
+				 global_address(dice, GLOBAL_CLOCK_SELECT),
+				 &clock, 4);
+	if (err < 0)
+		return err;
+
+	err = snd_pcm_new(dice->card, "DICE", 0, 1, 0, &pcm);
+	if (err < 0)
+		return err;
+	pcm->private_data = dice;
+	strcpy(pcm->name, dice->card->shortname);
+	dice->pcm = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
+	dice->pcm->ops = &ops;
+
+	return 0;
+}
+
+// TODO: implement these
+
+static long dice_hwdep_read(struct snd_hwdep *hwdep, char __user *buf,
+			    long count, loff_t *offset)
+{
+	return -EIO;
+}
+
+static int dice_hwdep_open(struct snd_hwdep *hwdep, struct file *file)
+{
+	return -EIO;
+}
+
+static int dice_hwdep_release(struct snd_hwdep *hwdep, struct file *file)
+{
+	return 0;
+}
+
+static unsigned int dice_hwdep_poll(struct snd_hwdep *hwdep, struct file *file,
+				    poll_table *wait)
+{
+	return POLLERR | POLLHUP;
+}
+
+static int dice_hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
+			    unsigned int cmd, unsigned long arg)
+{
+	return -EIO;
+}
+
+static int dice_create_hwdep(struct dice *dice)
+{
+	static const struct snd_hwdep_ops ops = {
+		.read         = dice_hwdep_read,
+		.open         = dice_hwdep_open,
+		.release      = dice_hwdep_release,
+		.poll         = dice_hwdep_poll,
+		.ioctl        = dice_hwdep_ioctl,
+		.ioctl_compat = dice_hwdep_ioctl,
+	};
+	struct snd_hwdep *hwdep;
+	int err;
+
+	err = snd_hwdep_new(dice->card, "DICE", 0, &hwdep);
+	if (err < 0)
+		return err;
+	strcpy(hwdep->name, "DICE");
+	hwdep->iface = SNDRV_HWDEP_IFACE_FW_DICE;
+	hwdep->ops = ops;
+	hwdep->private_data = dice;
+	hwdep->exclusive = true;
+
+	return 0;
+}
+
+static void dice_card_free(struct snd_card *card)
+{
+	struct dice *dice = card->private_data;
+
+	amdtp_out_stream_destroy(&dice->stream);
+	fw_core_remove_address_handler(&dice->notification_handler);
+	mutex_destroy(&dice->mutex);
+}
+
+static int dice_init_offsets(struct dice *dice)
+{
+	__be32 pointers[6];
+	unsigned int global_size, rx_size;
+	int err;
+
+	err = snd_fw_transaction(dice->unit, TCODE_READ_BLOCK_REQUEST,
+				 DICE_PRIVATE_SPACE, &pointers, 6 * 4);
+	if (err < 0)
+		return err;
+
+	dice->global_offset = be32_to_cpu(pointers[0]) * 4;
+	global_size = be32_to_cpu(pointers[1]);
+	dice->rx_offset = be32_to_cpu(pointers[4]) * 4;
+	rx_size = be32_to_cpu(pointers[5]);
+
+	/* some sanity checks to ensure that we actually have a DICE */
+	if (dice->global_offset < 10 * 4 || global_size < 0x168 / 4 ||
+	    dice->rx_offset < 10 * 4 || rx_size < 0x120 / 4) {
+		dev_err(&dice->unit->device, "invalid register pointers\n");
+		return -ENXIO;
+	}
+
+	return 0;
+}
+
+static void dice_card_strings(struct dice *dice)
+{
+	struct snd_card *card = dice->card;
+	struct fw_device *dev = fw_parent_device(dice->unit);
+	char vendor[32], model[32];
+	unsigned int i;
+	int err;
+
+	strcpy(card->driver, "DICE");
+
+	strcpy(card->shortname, "DICE");
+	BUILD_BUG_ON(NICK_NAME_SIZE < sizeof(card->shortname));
+	err = snd_fw_transaction(dice->unit, TCODE_READ_BLOCK_REQUEST,
+				 global_address(dice, GLOBAL_NICK_NAME),
+				 card->shortname, sizeof(card->shortname));
+	if (err >= 0) {
+		/* DICE strings are returned in "always-wrong" endianness */
+		BUILD_BUG_ON(sizeof(card->shortname) % 4 != 0);
+		for (i = 0; i < sizeof(card->shortname); i += 4)
+			swab32s((u32 *)&card->shortname[i]);
+		card->shortname[sizeof(card->shortname) - 1] = '\0';
+	}
+
+	strcpy(vendor, "?");
+	fw_csr_string(dev->config_rom + 5, CSR_VENDOR, vendor, sizeof(vendor));
+	strcpy(model, "?");
+	fw_csr_string(dice->unit->directory, CSR_MODEL, model, sizeof(model));
+	snprintf(card->longname, sizeof(card->longname),
+		 "%s %s, GUID %08x%08x at %s, S%d",
+		 vendor, model, dev->config_rom[3], dev->config_rom[4],
+		 dev_name(&dice->unit->device), 100 << dev->max_speed);
+
+	strcpy(card->mixername, "DICE");
+}
+
+static int dice_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
+{
+	struct snd_card *card;
+	struct dice *dice;
+	int err;
+
+	err = snd_card_create(-1, NULL, THIS_MODULE, sizeof(*dice), &card);
+	if (err < 0)
+		return err;
+	snd_card_set_dev(card, &unit->device);
+
+	dice = card->private_data;
+	dice->card = card;
+	mutex_init(&dice->mutex);
+	dice->unit = unit;
+
+	err = dice_init_offsets(dice);
+	if (err < 0)
+		goto err_mutex;
+
+	dice->notification_handler.length = 4;
+	dice->notification_handler.address_callback = dice_notification;
+	dice->notification_handler.callback_data = dice;
+	err = fw_core_add_address_handler(&dice->notification_handler,
+					  &fw_high_memory_region);
+	if (err < 0)
+		goto err_mutex;
+
+	err = fw_iso_resources_init(&dice->resources, unit);
+	if (err < 0)
+		goto err_notification_handler;
+	dice->resources.channels_mask = 0x00000000ffffffffuLL;
+
+	err = amdtp_out_stream_init(&dice->stream, unit, CIP_NONBLOCKING);
+	if (err < 0)
+		goto err_resources;
+
+	err = dice_owner_set(dice);
+	if (err < 0)
+		goto err_stream;
+
+	card->private_free = dice_card_free;
+
+	dice_card_strings(dice);
+
+	err = dice_create_pcm(dice);
+	if (err < 0)
+		goto error;
+
+	err = dice_create_hwdep(dice);
+	if (err < 0)
+		goto error;
+
+	err = snd_card_register(card);
+	if (err < 0)
+		goto error;
+
+	dev_set_drvdata(&unit->device, dice);
+
+	return 0;
+
+err_stream:
+	amdtp_out_stream_destroy(&dice->stream);
+err_resources:
+	fw_iso_resources_destroy(&dice->resources);
+err_notification_handler:
+	fw_core_remove_address_handler(&dice->notification_handler);
+err_mutex:
+	mutex_destroy(&dice->mutex);
+error:
+	snd_card_free(card);
+	return err;
+}
+
+static void dice_remove(struct fw_unit *unit)
+{
+	struct dice *dice = dev_get_drvdata(&unit->device);
+
+	snd_card_disconnect(dice->card);
+
+	mutex_lock(&dice->mutex);
+	amdtp_out_stream_pcm_abort(&dice->stream);
+	dice_stop_stream(dice);
+	dice_owner_clear(dice);
+	mutex_unlock(&dice->mutex);
+
+	snd_card_free_when_closed(dice->card);
+}
+
+static void dice_bus_reset(struct fw_unit *unit)
+{
+	struct dice *dice = dev_get_drvdata(&unit->device);
+
+	mutex_lock(&dice->mutex);
+	/*
+	 * XXX is the following true?
+	 * On a bus reset, the DICE firmware disables streaming and then goes
+	 * off contemplating its own navel for hundreds of milliseconds before
+	 * it can react to any of our attempts to reenable streaming.  This
+	 * means that we lose synchronization anyway, so we force our streams
+	 * to stop so that the application can restart them in an orderly
+	 * manner.
+	 */
+	dice_owner_update(dice);
+	amdtp_out_stream_pcm_abort(&dice->stream);
+	dice_stop_stream(dice);
+	mutex_unlock(&dice->mutex);
+}
+
+#define TC_OUI		0x000166
+#define DICE_INTERFACE	0x000001
+
+static const struct ieee1394_device_id dice_id_table[] = {
+	{
+		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
+				IEEE1394_MATCH_VERSION,
+		.specifier_id = TC_OUI,
+		.version      = DICE_INTERFACE,
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(ieee1394, dice_id_table);
+
+static struct fw_driver dice_driver = {
+	.driver   = {
+		.owner	= THIS_MODULE,
+		.name	= KBUILD_MODNAME,
+		.bus	= &fw_bus_type,
+	},
+	.probe    = dice_probe,
+	.update   = dice_bus_reset,
+	.remove   = dice_remove,
+	.id_table = dice_id_table,
+};
+
+static int __init alsa_dice_init(void)
+{
+	return driver_register(&dice_driver.driver);
+}
+
+static void __exit alsa_dice_exit(void)
+{
+	driver_unregister(&dice_driver.driver);
+}
+
+module_init(alsa_dice_init);
+module_exit(alsa_dice_exit);