ALSA: fireworks: Add transaction and some commands

Fireworks uses own command and response. This commit adds functionality to
transact and adds some commands required for sound card instance and kernel
streaming.

There are two ways to deliver substance of this transaction:
1.AV/C vendor dependent command for command/response
2.Async transaction to specific addresses for command/response

By way 1, I confirm AudioFire12 cannot correctly response to some commands with
firmware version 5.0 or later. This is also confirmed by FFADO. So this driver
implement way 2.

The address for response gives an issue. When this driver allocate own callback
function into the address, then no one can allocate its own callback function.
This situation is not good for applications in user-land. This issue is solved
in later commit.

I note there is a command to change the address for response if the device
supports. But this driver uses default value. So users should not execute this
command as long as hoping this driver works correctly.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 190 insertions, 0 deletions

diff --git a/sound/firewire/fireworks/fireworks_transaction.c b/sound/firewire/fireworks/fireworks_transaction.c
new file mode 100644
index 000000000000..aac91d8485d5
--- /dev/null
+++ b/sound/firewire/fireworks/fireworks_transaction.c
@@ -0,0 +1,190 @@
+/*
+ * fireworks_transaction.c - a part of driver for Fireworks based devices
+ *
+ * Copyright (c) 2013-2014 Takashi Sakamoto
+ *
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+
+/*
+ * Fireworks have its own transaction. The transaction can be delivered by AV/C
+ * Vendor Specific command. But at least Windows driver and firmware version 5.5
+ * or later don't use it.
+ *
+ * Transaction substance:
+ *  At first, 6 data exist. Following to the 6 data, parameters for each
+ *  commands exists. All of parameters are 32 bit alighed to big endian.
+ *   data[0]:	Length of transaction substance
+ *   data[1]:	Transaction version
+ *   data[2]:	Sequence number. This is incremented by the device
+ *   data[3]:	transaction category
+ *   data[4]:	transaction command
+ *   data[5]:	return value in response.
+ *   data[6-]:	parameters
+ *
+ * Transaction address:
+ *  command:	0xecc000000000
+ *  response:	0xecc080000000 (default)
+ *
+ * I note that the address for response can be changed by command. But this
+ * module uses the default address.
+ */
+#include "./fireworks.h"
+
+#define MEMORY_SPACE_EFW_COMMAND	0xecc000000000
+#define MEMORY_SPACE_EFW_RESPONSE	0xecc080000000
+
+#define ERROR_RETRIES 3
+#define ERROR_DELAY_MS 5
+#define EFC_TIMEOUT_MS 125
+
+static DEFINE_SPINLOCK(transaction_queues_lock);
+static LIST_HEAD(transaction_queues);
+
+enum transaction_queue_state {
+	STATE_PENDING,
+	STATE_BUS_RESET,
+	STATE_COMPLETE
+};
+
+struct transaction_queue {
+	struct list_head list;
+	struct fw_unit *unit;
+	void *buf;
+	unsigned int size;
+	u32 seqnum;
+	enum transaction_queue_state state;
+	wait_queue_head_t wait;
+};
+
+int snd_efw_transaction_run(struct fw_unit *unit,
+			    const void *cmd, unsigned int cmd_size,
+			    void *resp, unsigned int resp_size)
+{
+	struct transaction_queue t;
+	unsigned int tries;
+	int ret;
+
+	t.unit = unit;
+	t.buf = resp;
+	t.size = resp_size;
+	t.seqnum = be32_to_cpu(((struct snd_efw_transaction *)cmd)->seqnum) + 1;
+	t.state = STATE_PENDING;
+	init_waitqueue_head(&t.wait);
+
+	spin_lock_irq(&transaction_queues_lock);
+	list_add_tail(&t.list, &transaction_queues);
+	spin_unlock_irq(&transaction_queues_lock);
+
+	tries = 0;
+	do {
+		ret = snd_fw_transaction(unit, TCODE_WRITE_BLOCK_REQUEST,
+					 MEMORY_SPACE_EFW_COMMAND,
+					 (void *)cmd, cmd_size, 0);
+		if (ret < 0)
+			break;
+
+		wait_event_timeout(t.wait, t.state != STATE_PENDING,
+				   msecs_to_jiffies(EFC_TIMEOUT_MS));
+
+		if (t.state == STATE_COMPLETE) {
+			ret = t.size;
+			break;
+		} else if (t.state == STATE_BUS_RESET) {
+			msleep(ERROR_DELAY_MS);
+		} else if (++tries >= ERROR_RETRIES) {
+			dev_err(&t.unit->device, "EFW transaction timed out\n");
+			ret = -EIO;
+			break;
+		}
+	} while (1);
+
+	spin_lock_irq(&transaction_queues_lock);
+	list_del(&t.list);
+	spin_unlock_irq(&transaction_queues_lock);
+
+	return ret;
+}
+
+static void
+efw_response(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 fw_device *device;
+	struct transaction_queue *t;
+	unsigned long flags;
+	int rcode;
+	u32 seqnum;
+
+	rcode = RCODE_TYPE_ERROR;
+	if (length < sizeof(struct snd_efw_transaction)) {
+		rcode = RCODE_DATA_ERROR;
+		goto end;
+	} else if (offset != MEMORY_SPACE_EFW_RESPONSE) {
+		rcode = RCODE_ADDRESS_ERROR;
+		goto end;
+	}
+
+	seqnum = be32_to_cpu(((struct snd_efw_transaction *)data)->seqnum);
+
+	spin_lock_irqsave(&transaction_queues_lock, flags);
+	list_for_each_entry(t, &transaction_queues, list) {
+		device = fw_parent_device(t->unit);
+		if ((device->card != card) ||
+		    (device->generation != generation))
+			continue;
+		smp_rmb();	/* node_id vs. generation */
+		if (device->node_id != source)
+			continue;
+
+		if ((t->state == STATE_PENDING) && (t->seqnum == seqnum)) {
+			t->state = STATE_COMPLETE;
+			t->size = min_t(unsigned int, length, t->size);
+			memcpy(t->buf, data, t->size);
+			wake_up(&t->wait);
+			rcode = RCODE_COMPLETE;
+		}
+	}
+	spin_unlock_irqrestore(&transaction_queues_lock, flags);
+end:
+	fw_send_response(card, request, rcode);
+}
+
+void snd_efw_transaction_bus_reset(struct fw_unit *unit)
+{
+	struct transaction_queue *t;
+
+	spin_lock_irq(&transaction_queues_lock);
+	list_for_each_entry(t, &transaction_queues, list) {
+		if ((t->unit == unit) &&
+		    (t->state == STATE_PENDING)) {
+			t->state = STATE_BUS_RESET;
+			wake_up(&t->wait);
+		}
+	}
+	spin_unlock_irq(&transaction_queues_lock);
+}
+
+static struct fw_address_handler resp_register_handler = {
+	.length = SND_EFW_RESPONSE_MAXIMUM_BYTES,
+	.address_callback = efw_response
+};
+
+int snd_efw_transaction_register(void)
+{
+	static const struct fw_address_region resp_register_region = {
+		.start	= MEMORY_SPACE_EFW_RESPONSE,
+		.end	= MEMORY_SPACE_EFW_RESPONSE +
+			  SND_EFW_RESPONSE_MAXIMUM_BYTES
+	};
+	return fw_core_add_address_handler(&resp_register_handler,
+					   &resp_register_region);
+}
+
+void snd_efw_transaction_unregister(void)
+{
+	WARN_ON(!list_empty(&transaction_queues));
+	fw_core_remove_address_handler(&resp_register_handler);
+}