1 files changed, 137 insertions, 0 deletions
diff --git a/sound/firewire/motu/motu-transaction.c b/sound/firewire/motu/motu-transaction.c
new file mode 100644
index 000000000..7fc30091e
--- /dev/null
+++ b/sound/firewire/motu/motu-transaction.c
@@ -0,0 +1,137 @@
+/*
+ * motu-transaction.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ *
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+
+
+#include "motu.h"
+
+#define SND_MOTU_ADDR_BASE	0xfffff0000000ULL
+#define ASYNC_ADDR_HI  0x0b04
+#define ASYNC_ADDR_LO  0x0b08
+
+int snd_motu_transaction_read(struct snd_motu *motu, u32 offset, __be32 *reg,
+			      size_t size)
+{
+	int tcode;
+
+	if (size % sizeof(__be32) > 0 || size <= 0)
+		return -EINVAL;
+	if (size == sizeof(__be32))
+		tcode = TCODE_READ_QUADLET_REQUEST;
+	else
+		tcode = TCODE_READ_BLOCK_REQUEST;
+
+	return snd_fw_transaction(motu->unit, tcode,
+				  SND_MOTU_ADDR_BASE + offset, reg, size, 0);
+}
+
+int snd_motu_transaction_write(struct snd_motu *motu, u32 offset, __be32 *reg,
+			       size_t size)
+{
+	int tcode;
+
+	if (size % sizeof(__be32) > 0 || size <= 0)
+		return -EINVAL;
+	if (size == sizeof(__be32))
+		tcode = TCODE_WRITE_QUADLET_REQUEST;
+	else
+		tcode = TCODE_WRITE_BLOCK_REQUEST;
+
+	return snd_fw_transaction(motu->unit, tcode,
+				  SND_MOTU_ADDR_BASE + offset, reg, size, 0);
+}
+
+static void handle_message(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 snd_motu *motu = callback_data;
+	__be32 *buf = (__be32 *)data;
+	unsigned long flags;
+
+	if (tcode != TCODE_WRITE_QUADLET_REQUEST) {
+		fw_send_response(card, request, RCODE_COMPLETE);
+		return;
+	}
+
+	if (offset != motu->async_handler.offset || length != 4) {
+		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
+		return;
+	}
+
+	spin_lock_irqsave(&motu->lock, flags);
+	motu->msg = be32_to_cpu(*buf);
+	spin_unlock_irqrestore(&motu->lock, flags);
+
+	fw_send_response(card, request, RCODE_COMPLETE);
+
+	wake_up(&motu->hwdep_wait);
+}
+
+int snd_motu_transaction_reregister(struct snd_motu *motu)
+{
+	struct fw_device *device = fw_parent_device(motu->unit);
+	__be32 data;
+	int err;
+
+	if (motu->async_handler.callback_data == NULL)
+		return -EINVAL;
+
+	/* Register messaging address. Block transaction is not allowed. */
+	data = cpu_to_be32((device->card->node_id << 16) |
+			   (motu->async_handler.offset >> 32));
+	err = snd_motu_transaction_write(motu, ASYNC_ADDR_HI, &data,
+					 sizeof(data));
+	if (err < 0)
+		return err;
+
+	data = cpu_to_be32(motu->async_handler.offset);
+	return snd_motu_transaction_write(motu, ASYNC_ADDR_LO, &data,
+					  sizeof(data));
+}
+
+int snd_motu_transaction_register(struct snd_motu *motu)
+{
+	static const struct fw_address_region resp_register_region = {
+		.start	= 0xffffe0000000ull,
+		.end	= 0xffffe000ffffull,
+	};
+	int err;
+
+	/* Perhaps, 4 byte messages are transferred. */
+	motu->async_handler.length = 4;
+	motu->async_handler.address_callback = handle_message;
+	motu->async_handler.callback_data = motu;
+
+	err = fw_core_add_address_handler(&motu->async_handler,
+					  &resp_register_region);
+	if (err < 0)
+		return err;
+
+	err = snd_motu_transaction_reregister(motu);
+	if (err < 0) {
+		fw_core_remove_address_handler(&motu->async_handler);
+		motu->async_handler.address_callback = NULL;
+	}
+
+	return err;
+}
+
+void snd_motu_transaction_unregister(struct snd_motu *motu)
+{
+	__be32 data;
+
+	if (motu->async_handler.address_callback != NULL)
+		fw_core_remove_address_handler(&motu->async_handler);
+	motu->async_handler.address_callback = NULL;
+
+	/* Unregister the address. */
+	data = cpu_to_be32(0x00000000);
+	snd_motu_transaction_write(motu, ASYNC_ADDR_HI, &data, sizeof(data));
+	snd_motu_transaction_write(motu, ASYNC_ADDR_LO, &data, sizeof(data));
+}