sound/firewire/fireworks/fireworks_transaction.c - arm/linux - Git at Google

 /*
  * 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 frame or usual asynchronous transaction. At least,
  * Windows driver and firmware version 5.5 or later don't use AV/C command.
  *
  * Transaction substance:
  *  At first, 6 data exist. Following to the data, parameters for each command
  *  exist. All of the parameters are 32 bit aligned 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	0xecc000000000ULL
 #define MEMORY_SPACE_EFW_RESPONSE	0xecc080000000ULL

 #define ERROR_RETRIES 3
 #define ERROR_DELAY_MS 5
 #define EFC_TIMEOUT_MS 125

 static DEFINE_SPINLOCK(instances_lock);
 static struct snd_efw *instances[SNDRV_CARDS] = SNDRV_DEFAULT_PTR;

 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_cmd(struct fw_unit *unit,
 			    const void *cmd, unsigned int size)
 {
 	return snd_fw_transaction(unit, TCODE_WRITE_BLOCK_REQUEST,
 				  MEMORY_SPACE_EFW_COMMAND,
 				  (void *)cmd, size, 0);
 }

 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_efw_transaction_cmd(t.unit, (void *)cmd, cmd_size);
 		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
 copy_resp_to_buf(struct snd_efw *efw, void *data, size_t length, int *rcode)
 {
 	size_t capacity, till_end;
 	struct snd_efw_transaction *t;

 	t = (struct snd_efw_transaction *)data;
 	length = min_t(size_t, be32_to_cpu(t->length) * sizeof(u32), length);

 	spin_lock_irq(&efw->lock);

 	if (efw->push_ptr < efw->pull_ptr)
 		capacity = (unsigned int)(efw->pull_ptr - efw->push_ptr);
 	else
 		capacity = snd_efw_resp_buf_size -
 			   (unsigned int)(efw->push_ptr - efw->pull_ptr);

 	/* confirm enough space for this response */
 	if (capacity < length) {
 		*rcode = RCODE_CONFLICT_ERROR;
 		goto end;
 	}

 	/* copy to ring buffer */
 	while (length > 0) {
 		till_end = snd_efw_resp_buf_size -
 			   (unsigned int)(efw->push_ptr - efw->resp_buf);
 		till_end = min_t(unsigned int, length, till_end);

 		memcpy(efw->push_ptr, data, till_end);

 		efw->push_ptr += till_end;
 		if (efw->push_ptr >= efw->resp_buf + snd_efw_resp_buf_size)
 			efw->push_ptr -= snd_efw_resp_buf_size;

 		length -= till_end;
 		data += till_end;
 	}

 	/* for hwdep */
 	wake_up(&efw->hwdep_wait);

 	*rcode = RCODE_COMPLETE;
 end:
 	spin_unlock_irq(&efw->lock);
 }

 static void
 handle_resp_for_user(struct fw_card *card, int generation, int source,
 		     void *data, size_t length, int *rcode)
 {
 	struct fw_device *device;
 	struct snd_efw *efw;
 	unsigned int i;

 	spin_lock_irq(&instances_lock);

 	for (i = 0; i < SNDRV_CARDS; i++) {
 		efw = instances[i];
 		if (efw == NULL)
 			continue;
 		device = fw_parent_device(efw->unit);
 		if ((device->card != card) ||
 		    (device->generation != generation))
 			continue;
 		smp_rmb();	/* node id vs. generation */
 		if (device->node_id != source)
 			continue;

 		break;
 	}
 	if (i == SNDRV_CARDS)
 		goto end;

 	copy_resp_to_buf(efw, data, length, rcode);
 end:
 	spin_unlock_irq(&instances_lock);
 }

 static void
 handle_resp_for_kernel(struct fw_card *card, int generation, int source,
 		       void *data, size_t length, int *rcode, u32 seqnum)
 {
 	struct fw_device *device;
 	struct transaction_queue *t;
 	unsigned long flags;

 	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);
 }

 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)
 {
 	int rcode, dummy;
 	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);
 	if (seqnum > SND_EFW_TRANSACTION_USER_SEQNUM_MAX + 1) {
 		handle_resp_for_kernel(card, generation, source,
 				       data, length, &rcode, seqnum);
 		if (snd_efw_resp_buf_debug)
 			handle_resp_for_user(card, generation, source,
 					     data, length, &dummy);
 	} else {
 		handle_resp_for_user(card, generation, source,
 				     data, length, &rcode);
 	}
 end:
 	fw_send_response(card, request, rcode);
 }

 void snd_efw_transaction_add_instance(struct snd_efw *efw)
 {
 	unsigned int i;

 	spin_lock_irq(&instances_lock);

 	for (i = 0; i < SNDRV_CARDS; i++) {
 		if (instances[i] != NULL)
 			continue;
 		instances[i] = efw;
 		break;
 	}

 	spin_unlock_irq(&instances_lock);
 }

 void snd_efw_transaction_remove_instance(struct snd_efw *efw)
 {
 	unsigned int i;

 	spin_lock_irq(&instances_lock);

 	for (i = 0; i < SNDRV_CARDS; i++) {
 		if (instances[i] != efw)
 			continue;
 		instances[i] = NULL;
 	}

 	spin_unlock_irq(&instances_lock);
 }

 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);
 }
	/*
	* 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 frame or usual asynchronous transaction. At least,
	* Windows driver and firmware version 5.5 or later don't use AV/C command.
	*
	* Transaction substance:
	* At first, 6 data exist. Following to the data, parameters for each command
	* exist. All of the parameters are 32 bit aligned 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 0xecc000000000ULL
	#define MEMORY_SPACE_EFW_RESPONSE 0xecc080000000ULL

	#define ERROR_RETRIES 3
	#define ERROR_DELAY_MS 5
	#define EFC_TIMEOUT_MS 125

	static DEFINE_SPINLOCK(instances_lock);
	static struct snd_efw *instances[SNDRV_CARDS] = SNDRV_DEFAULT_PTR;

	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_cmd(struct fw_unit *unit,
	const void *cmd, unsigned int size)
	{
	return snd_fw_transaction(unit, TCODE_WRITE_BLOCK_REQUEST,
	MEMORY_SPACE_EFW_COMMAND,
	(void *)cmd, size, 0);
	}

	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_efw_transaction_cmd(t.unit, (void *)cmd, cmd_size);
	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
	copy_resp_to_buf(struct snd_efw efw, void data, size_t length, int *rcode)
	{
	size_t capacity, till_end;
	struct snd_efw_transaction *t;

	t = (struct snd_efw_transaction *)data;
	length = min_t(size_t, be32_to_cpu(t->length) * sizeof(u32), length);

	spin_lock_irq(&efw->lock);

	if (efw->push_ptr < efw->pull_ptr)
	capacity = (unsigned int)(efw->pull_ptr - efw->push_ptr);
	else
	capacity = snd_efw_resp_buf_size -
	(unsigned int)(efw->push_ptr - efw->pull_ptr);

	/* confirm enough space for this response */
	if (capacity < length) {
	*rcode = RCODE_CONFLICT_ERROR;
	goto end;
	}

	/* copy to ring buffer */
	while (length > 0) {
	till_end = snd_efw_resp_buf_size -
	(unsigned int)(efw->push_ptr - efw->resp_buf);
	till_end = min_t(unsigned int, length, till_end);

	memcpy(efw->push_ptr, data, till_end);

	efw->push_ptr += till_end;
	if (efw->push_ptr >= efw->resp_buf + snd_efw_resp_buf_size)
	efw->push_ptr -= snd_efw_resp_buf_size;

	length -= till_end;
	data += till_end;
	}

	/* for hwdep */
	wake_up(&efw->hwdep_wait);

	*rcode = RCODE_COMPLETE;
	end:
	spin_unlock_irq(&efw->lock);
	}

	static void
	handle_resp_for_user(struct fw_card *card, int generation, int source,
	void data, size_t length, int rcode)
	{
	struct fw_device *device;
	struct snd_efw *efw;
	unsigned int i;

	spin_lock_irq(&instances_lock);

	for (i = 0; i < SNDRV_CARDS; i++) {
	efw = instances[i];
	if (efw == NULL)
	continue;
	device = fw_parent_device(efw->unit);
	if ((device->card != card) \|\|
	(device->generation != generation))
	continue;
	smp_rmb(); /* node id vs. generation */
	if (device->node_id != source)
	continue;

	break;
	}
	if (i == SNDRV_CARDS)
	goto end;

	copy_resp_to_buf(efw, data, length, rcode);
	end:
	spin_unlock_irq(&instances_lock);
	}

	static void
	handle_resp_for_kernel(struct fw_card *card, int generation, int source,
	void data, size_t length, int rcode, u32 seqnum)
	{
	struct fw_device *device;
	struct transaction_queue *t;
	unsigned long flags;

	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);
	}

	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)
	{
	int rcode, dummy;
	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);
	if (seqnum > SND_EFW_TRANSACTION_USER_SEQNUM_MAX + 1) {
	handle_resp_for_kernel(card, generation, source,
	data, length, &rcode, seqnum);
	if (snd_efw_resp_buf_debug)
	handle_resp_for_user(card, generation, source,
	data, length, &dummy);
	} else {
	handle_resp_for_user(card, generation, source,
	data, length, &rcode);
	}
	end:
	fw_send_response(card, request, rcode);
	}

	void snd_efw_transaction_add_instance(struct snd_efw *efw)
	{
	unsigned int i;

	spin_lock_irq(&instances_lock);

	for (i = 0; i < SNDRV_CARDS; i++) {
	if (instances[i] != NULL)
	continue;
	instances[i] = efw;
	break;
	}

	spin_unlock_irq(&instances_lock);
	}

	void snd_efw_transaction_remove_instance(struct snd_efw *efw)
	{
	unsigned int i;

	spin_lock_irq(&instances_lock);

	for (i = 0; i < SNDRV_CARDS; i++) {
	if (instances[i] != efw)
	continue;
	instances[i] = NULL;
	}

	spin_unlock_irq(&instances_lock);
	}

	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);
	}