ALSA: add LaCie FireWire Speakers/Griffin FireWave Surround driver

Add a driver for two playback-only FireWire devices based on the OXFW970
chip.

v2: better AMDTP API abstraction; fix fw_unit leak; small fixes
v3: cache the iPCR value
v4: FireWave constraints; fix fw_device reference counting;
    fix PCR caching; small changes and fixes
v5: volume/mute support; fix crashing due to pcm stop races
v6: fix build; one-channel volume for LaCie
v7: use signed values to make volume (range checks) work; fix function
    block IDs for volume/mute; always use channel 0 for LaCie volume

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Tested-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 39 insertions, 0 deletions

diff --git a/sound/firewire/iso-resources.h b/sound/firewire/iso-resources.h
new file mode 100644
index 00000000000..9feb9f8d474
--- /dev/null
+++ b/sound/firewire/iso-resources.h
@@ -0,0 +1,39 @@
+#ifndef SOUND_FIREWIRE_ISO_RESOURCES_H_INCLUDED
+#define SOUND_FIREWIRE_ISO_RESOURCES_H_INCLUDED
+
+#include <linux/mutex.h>
+#include <linux/types.h>
+
+struct fw_unit;
+
+/**
+ * struct fw_iso_resources - manages channel/bandwidth allocation
+ * @channels_mask: if the device does not support all channel numbers, set this
+ *                 bit mask to something else than the default (all ones)
+ *
+ * This structure manages (de)allocation of isochronous resources (channel and
+ * bandwidth) for one isochronous stream.
+ */
+struct fw_iso_resources {
+        u64 channels_mask;
+        /* private: */
+        struct fw_unit *unit;
+        struct mutex mutex;
+        unsigned int channel;
+        unsigned int bandwidth; /* in bandwidth units, without overhead */
+        unsigned int bandwidth_overhead;
+        int generation; /* in which allocation is valid */
+        bool allocated;
+        __be32 buffer[2];
+};
+
+void fw_iso_resources_init(struct fw_iso_resources *r,
+                           struct fw_unit *unit);
+void fw_iso_resources_destroy(struct fw_iso_resources *r);
+
+int fw_iso_resources_allocate(struct fw_iso_resources *r,
+                              unsigned int max_payload_bytes, int speed);
+int fw_iso_resources_update(struct fw_iso_resources *r);
+void fw_iso_resources_free(struct fw_iso_resources *r);
+
+#endif