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 <clemens@ladisch.de>

include/uapi/sound/Kbuild

@@ -5,6 +5,7 @@ header-y += asound_fm.h
 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

@@ -93,9 +93,10 @@ enum {
 	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

@@ -0,0 +1,51 @@
+#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