[net-next-2.6.git] / drivers / firewire / core-iso.c

/*
 * Isochronous I/O functionality:
 *   - Isochronous DMA context management
 *   - Isochronous bus resource management (channels, bandwidth), client side
 *
 * Copyright (C) 2006 Kristian Hoegsberg <krh@bitplanet.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/firewire.h>
#include <linux/firewire-constants.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/vmalloc.h>

#include <asm/byteorder.h>

#include "core.h"

/*
 * Isochronous DMA context management
 */

int fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card,
		       int page_count, enum dma_data_direction direction)
{
	int i, j;
	dma_addr_t address;

	buffer->page_count = page_count;
	buffer->direction = direction;

	buffer->pages = kmalloc(page_count * sizeof(buffer->pages[0]),
				GFP_KERNEL);
	if (buffer->pages == NULL)
		goto out;

	for (i = 0; i < buffer->page_count; i++) {
		buffer->pages[i] = alloc_page(GFP_KERNEL | GFP_DMA32 | __GFP_ZERO);
		if (buffer->pages[i] == NULL)
			goto out_pages;

		address = dma_map_page(card->device, buffer->pages[i],
				       0, PAGE_SIZE, direction);
		if (dma_mapping_error(card->device, address)) {
			__free_page(buffer->pages[i]);
			goto out_pages;
		}
		set_page_private(buffer->pages[i], address);
	}

	return 0;

 out_pages:
	for (j = 0; j < i; j++) {
		address = page_private(buffer->pages[j]);
		dma_unmap_page(card->device, address,
			       PAGE_SIZE, direction);
		__free_page(buffer->pages[j]);
	}
	kfree(buffer->pages);
 out:
	buffer->pages = NULL;

	return -ENOMEM;
}
EXPORT_SYMBOL(fw_iso_buffer_init);

int fw_iso_buffer_map(struct fw_iso_buffer *buffer, struct vm_area_struct *vma)
{
	unsigned long uaddr;
	int i, err;

	uaddr = vma->vm_start;
	for (i = 0; i < buffer->page_count; i++) {
		err = vm_insert_page(vma, uaddr, buffer->pages[i]);
		if (err)
			return err;

		uaddr += PAGE_SIZE;
	}

	return 0;
}

void fw_iso_buffer_destroy(struct fw_iso_buffer *buffer,
			   struct fw_card *card)
{
	int i;
	dma_addr_t address;

	for (i = 0; i < buffer->page_count; i++) {
		address = page_private(buffer->pages[i]);
		dma_unmap_page(card->device, address,
			       PAGE_SIZE, buffer->direction);
		__free_page(buffer->pages[i]);
	}

	kfree(buffer->pages);
	buffer->pages = NULL;
}
EXPORT_SYMBOL(fw_iso_buffer_destroy);

/* Convert DMA address to offset into virtually contiguous buffer. */
size_t fw_iso_buffer_lookup(struct fw_iso_buffer *buffer, dma_addr_t completed)
{
	int i;
	dma_addr_t address;
	ssize_t offset;

	for (i = 0; i < buffer->page_count; i++) {
		address = page_private(buffer->pages[i]);
		offset = (ssize_t)completed - (ssize_t)address;
		if (offset > 0 && offset <= PAGE_SIZE)
			return (i << PAGE_SHIFT) + offset;
	}

	return 0;
}

struct fw_iso_context *fw_iso_context_create(struct fw_card *card,
		int type, int channel, int speed, size_t header_size,
		fw_iso_callback_t callback, void *callback_data)
{
	struct fw_iso_context *ctx;

	ctx = card->driver->allocate_iso_context(card,
						 type, channel, header_size);
	if (IS_ERR(ctx))
		return ctx;

	ctx->card = card;
	ctx->type = type;
	ctx->channel = channel;
	ctx->speed = speed;
	ctx->header_size = header_size;
	ctx->callback.sc = callback;
	ctx->callback_data = callback_data;

	return ctx;
}
EXPORT_SYMBOL(fw_iso_context_create);

void fw_iso_context_destroy(struct fw_iso_context *ctx)
{
	ctx->card->driver->free_iso_context(ctx);
}
EXPORT_SYMBOL(fw_iso_context_destroy);

int fw_iso_context_start(struct fw_iso_context *ctx,
			 int cycle, int sync, int tags)
{
	return ctx->card->driver->start_iso(ctx, cycle, sync, tags);
}
EXPORT_SYMBOL(fw_iso_context_start);

int fw_iso_context_set_channels(struct fw_iso_context *ctx, u64 *channels)
{
	return ctx->card->driver->set_iso_channels(ctx, channels);
}

int fw_iso_context_queue(struct fw_iso_context *ctx,
			 struct fw_iso_packet *packet,
			 struct fw_iso_buffer *buffer,
			 unsigned long payload)
{
	return ctx->card->driver->queue_iso(ctx, packet, buffer, payload);
}
EXPORT_SYMBOL(fw_iso_context_queue);

int fw_iso_context_stop(struct fw_iso_context *ctx)
{
	return ctx->card->driver->stop_iso(ctx);
}
EXPORT_SYMBOL(fw_iso_context_stop);

/*
 * Isochronous bus resource management (channels, bandwidth), client side
 */

static int manage_bandwidth(struct fw_card *card, int irm_id, int generation,
			    int bandwidth, bool allocate, __be32 data[2])
{
	int try, new, old = allocate ? BANDWIDTH_AVAILABLE_INITIAL : 0;

	/*
	 * On a 1394a IRM with low contention, try < 1 is enough.
	 * On a 1394-1995 IRM, we need at least try < 2.
	 * Let's just do try < 5.
	 */
	for (try = 0; try < 5; try++) {
		new = allocate ? old - bandwidth : old + bandwidth;
		if (new < 0 || new > BANDWIDTH_AVAILABLE_INITIAL)
			return -EBUSY;

		data[0] = cpu_to_be32(old);
		data[1] = cpu_to_be32(new);
		switch (fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
				irm_id, generation, SCODE_100,
				CSR_REGISTER_BASE + CSR_BANDWIDTH_AVAILABLE,
				data, 8)) {
		case RCODE_GENERATION:
			/* A generation change frees all bandwidth. */
			return allocate ? -EAGAIN : bandwidth;

		case RCODE_COMPLETE:
			if (be32_to_cpup(data) == old)
				return bandwidth;

			old = be32_to_cpup(data);
			/* Fall through. */
		}
	}

	return -EIO;
}

static int manage_channel(struct fw_card *card, int irm_id, int generation,
		u32 channels_mask, u64 offset, bool allocate, __be32 data[2])
{
	__be32 c, all, old;
	int i, ret = -EIO, retry = 5;

	old = all = allocate ? cpu_to_be32(~0) : 0;

	for (i = 0; i < 32; i++) {
		if (!(channels_mask & 1 << i))
			continue;

		ret = -EBUSY;

		c = cpu_to_be32(1 << (31 - i));
		if ((old & c) != (all & c))
			continue;

		data[0] = old;
		data[1] = old ^ c;
		switch (fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
					   irm_id, generation, SCODE_100,
					   offset, data, 8)) {
		case RCODE_GENERATION:
			/* A generation change frees all channels. */
			return allocate ? -EAGAIN : i;

		case RCODE_COMPLETE:
			if (data[0] == old)
				return i;

			old = data[0];

			/* Is the IRM 1394a-2000 compliant? */
			if ((data[0] & c) == (data[1] & c))
				continue;

			/* 1394-1995 IRM, fall through to retry. */
		default:
			if (retry) {
				retry--;
				i--;
			} else {
				ret = -EIO;
			}
		}
	}

	return ret;
}

static void deallocate_channel(struct fw_card *card, int irm_id,
			       int generation, int channel, __be32 buffer[2])
{
	u32 mask;
	u64 offset;

	mask = channel < 32 ? 1 << channel : 1 << (channel - 32);
	offset = channel < 32 ? CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI :
				CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO;

	manage_channel(card, irm_id, generation, mask, offset, false, buffer);
}

/**
 * fw_iso_resource_manage() - Allocate or deallocate a channel and/or bandwidth
 *
 * In parameters: card, generation, channels_mask, bandwidth, allocate
 * Out parameters: channel, bandwidth
 * This function blocks (sleeps) during communication with the IRM.
 *
 * Allocates or deallocates at most one channel out of channels_mask.
 * channels_mask is a bitfield with MSB for channel 63 and LSB for channel 0.
 * (Note, the IRM's CHANNELS_AVAILABLE is a big-endian bitfield with MSB for
 * channel 0 and LSB for channel 63.)
 * Allocates or deallocates as many bandwidth allocation units as specified.
 *
 * Returns channel < 0 if no channel was allocated or deallocated.
 * Returns bandwidth = 0 if no bandwidth was allocated or deallocated.
 *
 * If generation is stale, deallocations succeed but allocations fail with
 * channel = -EAGAIN.
 *
 * If channel allocation fails, no bandwidth will be allocated either.
 * If bandwidth allocation fails, no channel will be allocated either.
 * But deallocations of channel and bandwidth are tried independently
 * of each other's success.
 */
void fw_iso_resource_manage(struct fw_card *card, int generation,
			    u64 channels_mask, int *channel, int *bandwidth,
			    bool allocate, __be32 buffer[2])
{
	u32 channels_hi = channels_mask;	/* channels 31...0 */
	u32 channels_lo = channels_mask >> 32;	/* channels 63...32 */
	int irm_id, ret, c = -EINVAL;

	spin_lock_irq(&card->lock);
	irm_id = card->irm_node->node_id;
	spin_unlock_irq(&card->lock);

	if (channels_hi)
		c = manage_channel(card, irm_id, generation, channels_hi,
				CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI,
				allocate, buffer);
	if (channels_lo && c < 0) {
		c = manage_channel(card, irm_id, generation, channels_lo,
				CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO,
				allocate, buffer);
		if (c >= 0)
			c += 32;
	}
	*channel = c;

	if (allocate && channels_mask != 0 && c < 0)
		*bandwidth = 0;

	if (*bandwidth == 0)
		return;

	ret = manage_bandwidth(card, irm_id, generation, *bandwidth,
			       allocate, buffer);
	if (ret < 0)
		*bandwidth = 0;

	if (allocate && ret < 0) {
		if (c >= 0)
			deallocate_channel(card, irm_id, generation, c, buffer);
		*channel = ret;
	}
}
Commit	Line	Data
c781c06d	1	/*
b1bda4cd JFSR	2	* Isochronous I/O functionality:
	3	* - Isochronous DMA context management
	4	* - Isochronous bus resource management (channels, bandwidth), client side
3038e353	5	*
3038e353 KH	6	* Copyright (C) 2006 Kristian Hoegsberg <krh@bitplanet.net>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software Foundation,
	20	* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	21	*/
	22
3038e353	23	#include <linux/dma-mapping.h>
b1bda4cd	24	#include <linux/errno.h>
77c9a5da	25	#include <linux/firewire.h>
b1bda4cd JFSR	26	#include <linux/firewire-constants.h>
b1bda4cd JFSR	27	#include <linux/kernel.h>
3038e353	28	#include <linux/mm.h>
5a0e3ad6	29	#include <linux/slab.h>
b1bda4cd JFSR	30	#include <linux/spinlock.h>
b1bda4cd JFSR	31	#include <linux/vmalloc.h>
3038e353	32
e8ca9702 SR	33	#include <asm/byteorder.h>
e8ca9702 SR	34
77c9a5da	35	#include "core.h"
b1bda4cd JFSR	36
	37	/*
	38	* Isochronous DMA context management
	39	*/
3038e353	40
53dca511 SR	41	int fw_iso_buffer_init(struct fw_iso_buffer buffer, struct fw_card card,
53dca511 SR	42	int page_count, enum dma_data_direction direction)
3038e353	43	{
2dbd7d7e	44	int i, j;
9aad8125 KH	45	dma_addr_t address;
	46
	47	buffer->page_count = page_count;
	48	buffer->direction = direction;
	49
	50	buffer->pages = kmalloc(page_count * sizeof(buffer->pages[0]),
	51	GFP_KERNEL);
	52	if (buffer->pages == NULL)
	53	goto out;
	54
	55	for (i = 0; i < buffer->page_count; i++) {
68be3fa1	56	buffer->pages[i] = alloc_page(GFP_KERNEL \| GFP_DMA32 \| __GFP_ZERO);
9aad8125 KH	57	if (buffer->pages[i] == NULL)
9aad8125 KH	58	goto out_pages;
373b2edd	59
9aad8125 KH	60	address = dma_map_page(card->device, buffer->pages[i],
9aad8125 KH	61	0, PAGE_SIZE, direction);
8d8bb39b	62	if (dma_mapping_error(card->device, address)) {
9aad8125 KH	63	__free_page(buffer->pages[i]);
	64	goto out_pages;
	65	}
	66	set_page_private(buffer->pages[i], address);
3038e353 KH	67	}
	68
	69	return 0;
82eff9db	70
9aad8125 KH	71	out_pages:
	72	for (j = 0; j < i; j++) {
	73	address = page_private(buffer->pages[j]);
	74	dma_unmap_page(card->device, address,
29ad14cd	75	PAGE_SIZE, direction);
9aad8125 KH	76	__free_page(buffer->pages[j]);
	77	}
	78	kfree(buffer->pages);
	79	out:
	80	buffer->pages = NULL;
e1eff7a3	81
2dbd7d7e	82	return -ENOMEM;
9aad8125	83	}
c76acec6	84	EXPORT_SYMBOL(fw_iso_buffer_init);
9aad8125 KH	85
	86	int fw_iso_buffer_map(struct fw_iso_buffer buffer, struct vm_area_struct vma)
	87	{
	88	unsigned long uaddr;
e1eff7a3	89	int i, err;
9aad8125 KH	90
	91	uaddr = vma->vm_start;
	92	for (i = 0; i < buffer->page_count; i++) {
e1eff7a3 SR	93	err = vm_insert_page(vma, uaddr, buffer->pages[i]);
	94	if (err)
	95	return err;
	96
9aad8125 KH	97	uaddr += PAGE_SIZE;
	98	}
	99
	100	return 0;
3038e353 KH	101	}
3038e353 KH	102
9aad8125 KH	103	void fw_iso_buffer_destroy(struct fw_iso_buffer *buffer,
9aad8125 KH	104	struct fw_card *card)
3038e353 KH	105	{
3038e353 KH	106	int i;
9aad8125	107	dma_addr_t address;
3038e353	108
9aad8125 KH	109	for (i = 0; i < buffer->page_count; i++) {
	110	address = page_private(buffer->pages[i]);
	111	dma_unmap_page(card->device, address,
29ad14cd	112	PAGE_SIZE, buffer->direction);
9aad8125 KH	113	__free_page(buffer->pages[i]);
9aad8125 KH	114	}
3038e353	115
9aad8125 KH	116	kfree(buffer->pages);
9aad8125 KH	117	buffer->pages = NULL;
3038e353	118	}
c76acec6	119	EXPORT_SYMBOL(fw_iso_buffer_destroy);
3038e353	120
872e330e SR	121	/* Convert DMA address to offset into virtually contiguous buffer. */
	122	size_t fw_iso_buffer_lookup(struct fw_iso_buffer *buffer, dma_addr_t completed)
	123	{
	124	int i;
	125	dma_addr_t address;
	126	ssize_t offset;
	127
	128	for (i = 0; i < buffer->page_count; i++) {
	129	address = page_private(buffer->pages[i]);
	130	offset = (ssize_t)completed - (ssize_t)address;
	131	if (offset > 0 && offset <= PAGE_SIZE)
	132	return (i << PAGE_SHIFT) + offset;
	133	}
	134
	135	return 0;
	136	}
	137
53dca511 SR	138	struct fw_iso_context fw_iso_context_create(struct fw_card card,
	139	int type, int channel, int speed, size_t header_size,
	140	fw_iso_callback_t callback, void *callback_data)
3038e353 KH	141	{
3038e353 KH	142	struct fw_iso_context *ctx;
3038e353	143
4817ed24 SR	144	ctx = card->driver->allocate_iso_context(card,
4817ed24 SR	145	type, channel, header_size);
3038e353 KH	146	if (IS_ERR(ctx))
	147	return ctx;
	148
	149	ctx->card = card;
	150	ctx->type = type;
21efb3cf KH	151	ctx->channel = channel;
21efb3cf KH	152	ctx->speed = speed;
295e3feb	153	ctx->header_size = header_size;
872e330e	154	ctx->callback.sc = callback;
3038e353 KH	155	ctx->callback_data = callback_data;
3038e353 KH	156
3038e353 KH	157	return ctx;
3038e353 KH	158	}
c76acec6	159	EXPORT_SYMBOL(fw_iso_context_create);
3038e353 KH	160
	161	void fw_iso_context_destroy(struct fw_iso_context *ctx)
	162	{
872e330e	163	ctx->card->driver->free_iso_context(ctx);
3038e353	164	}
c76acec6	165	EXPORT_SYMBOL(fw_iso_context_destroy);
3038e353	166
53dca511 SR	167	int fw_iso_context_start(struct fw_iso_context *ctx,
53dca511 SR	168	int cycle, int sync, int tags)
3038e353	169	{
eb0306ea	170	return ctx->card->driver->start_iso(ctx, cycle, sync, tags);
3038e353	171	}
c76acec6	172	EXPORT_SYMBOL(fw_iso_context_start);
3038e353	173
872e330e SR	174	int fw_iso_context_set_channels(struct fw_iso_context ctx, u64 channels)
	175	{
	176	return ctx->card->driver->set_iso_channels(ctx, channels);
	177	}
	178
53dca511 SR	179	int fw_iso_context_queue(struct fw_iso_context *ctx,
	180	struct fw_iso_packet *packet,
	181	struct fw_iso_buffer *buffer,
	182	unsigned long payload)
3038e353	183	{
872e330e	184	return ctx->card->driver->queue_iso(ctx, packet, buffer, payload);
3038e353	185	}
c76acec6	186	EXPORT_SYMBOL(fw_iso_context_queue);
b8295668	187
53dca511	188	int fw_iso_context_stop(struct fw_iso_context *ctx)
b8295668 KH	189	{
	190	return ctx->card->driver->stop_iso(ctx);
	191	}
c76acec6	192	EXPORT_SYMBOL(fw_iso_context_stop);
b1bda4cd JFSR	193
	194	/*
	195	* Isochronous bus resource management (channels, bandwidth), client side
	196	*/
	197
	198	static int manage_bandwidth(struct fw_card *card, int irm_id, int generation,
6fdc0370	199	int bandwidth, bool allocate, __be32 data[2])
b1bda4cd	200	{
b1bda4cd JFSR	201	int try, new, old = allocate ? BANDWIDTH_AVAILABLE_INITIAL : 0;
	202
	203	/*
	204	* On a 1394a IRM with low contention, try < 1 is enough.
	205	* On a 1394-1995 IRM, we need at least try < 2.
	206	* Let's just do try < 5.
	207	*/
	208	for (try = 0; try < 5; try++) {
	209	new = allocate ? old - bandwidth : old + bandwidth;
	210	if (new < 0 \|\| new > BANDWIDTH_AVAILABLE_INITIAL)
d6372b6e	211	return -EBUSY;
b1bda4cd JFSR	212
	213	data[0] = cpu_to_be32(old);
	214	data[1] = cpu_to_be32(new);
	215	switch (fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
	216	irm_id, generation, SCODE_100,
	217	CSR_REGISTER_BASE + CSR_BANDWIDTH_AVAILABLE,
1821bc19	218	data, 8)) {
b1bda4cd JFSR	219	case RCODE_GENERATION:
	220	/* A generation change frees all bandwidth. */
	221	return allocate ? -EAGAIN : bandwidth;
	222
	223	case RCODE_COMPLETE:
	224	if (be32_to_cpup(data) == old)
	225	return bandwidth;
	226
	227	old = be32_to_cpup(data);
	228	/* Fall through. */
	229	}
	230	}
	231
	232	return -EIO;
	233	}
	234
	235	static int manage_channel(struct fw_card *card, int irm_id, int generation,
6fdc0370	236	u32 channels_mask, u64 offset, bool allocate, __be32 data[2])
b1bda4cd	237	{
6fdc0370	238	__be32 c, all, old;
d6372b6e	239	int i, ret = -EIO, retry = 5;
b1bda4cd	240
5d9cb7d2 SR	241	old = all = allocate ? cpu_to_be32(~0) : 0;
5d9cb7d2 SR	242
b1bda4cd	243	for (i = 0; i < 32; i++) {
5d9cb7d2	244	if (!(channels_mask & 1 << i))
b1bda4cd JFSR	245	continue;
b1bda4cd JFSR	246
d6372b6e CL	247	ret = -EBUSY;
d6372b6e CL	248
5d9cb7d2 SR	249	c = cpu_to_be32(1 << (31 - i));
5d9cb7d2 SR	250	if ((old & c) != (all & c))
b1bda4cd JFSR	251	continue;
	252
	253	data[0] = old;
	254	data[1] = old ^ c;
	255	switch (fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
	256	irm_id, generation, SCODE_100,
1821bc19	257	offset, data, 8)) {
b1bda4cd JFSR	258	case RCODE_GENERATION:
	259	/* A generation change frees all channels. */
	260	return allocate ? -EAGAIN : i;
	261
	262	case RCODE_COMPLETE:
	263	if (data[0] == old)
	264	return i;
	265
	266	old = data[0];
	267
	268	/* Is the IRM 1394a-2000 compliant? */
5d9cb7d2	269	if ((data[0] & c) == (data[1] & c))
b1bda4cd JFSR	270	continue;
	271
	272	/* 1394-1995 IRM, fall through to retry. */
	273	default:
3a1f0a0e CL	274	if (retry) {
3a1f0a0e CL	275	retry--;
b1bda4cd	276	i--;
d6372b6e CL	277	} else {
d6372b6e CL	278	ret = -EIO;
3a1f0a0e	279	}
b1bda4cd JFSR	280	}
	281	}
	282
d6372b6e	283	return ret;
b1bda4cd JFSR	284	}
	285
	286	static void deallocate_channel(struct fw_card *card, int irm_id,
6fdc0370	287	int generation, int channel, __be32 buffer[2])
b1bda4cd	288	{
5d9cb7d2	289	u32 mask;
b1bda4cd JFSR	290	u64 offset;
b1bda4cd JFSR	291
5d9cb7d2	292	mask = channel < 32 ? 1 << channel : 1 << (channel - 32);
b1bda4cd JFSR	293	offset = channel < 32 ? CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI :
	294	CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO;
	295
6fdc0370	296	manage_channel(card, irm_id, generation, mask, offset, false, buffer);
b1bda4cd JFSR	297	}
	298
	299	/**
656b7afd	300	* fw_iso_resource_manage() - Allocate or deallocate a channel and/or bandwidth
b1bda4cd JFSR	301	*
	302	* In parameters: card, generation, channels_mask, bandwidth, allocate
	303	* Out parameters: channel, bandwidth
	304	* This function blocks (sleeps) during communication with the IRM.
5d9cb7d2	305	*
b1bda4cd	306	* Allocates or deallocates at most one channel out of channels_mask.
5d9cb7d2 SR	307	* channels_mask is a bitfield with MSB for channel 63 and LSB for channel 0.
	308	* (Note, the IRM's CHANNELS_AVAILABLE is a big-endian bitfield with MSB for
	309	* channel 0 and LSB for channel 63.)
	310	* Allocates or deallocates as many bandwidth allocation units as specified.
b1bda4cd JFSR	311	*
	312	* Returns channel < 0 if no channel was allocated or deallocated.
	313	* Returns bandwidth = 0 if no bandwidth was allocated or deallocated.
	314	*
	315	* If generation is stale, deallocations succeed but allocations fail with
	316	* channel = -EAGAIN.
	317	*
5d9cb7d2	318	* If channel allocation fails, no bandwidth will be allocated either.
b1bda4cd	319	* If bandwidth allocation fails, no channel will be allocated either.
5d9cb7d2 SR	320	* But deallocations of channel and bandwidth are tried independently
5d9cb7d2 SR	321	* of each other's success.
b1bda4cd JFSR	322	*/
	323	void fw_iso_resource_manage(struct fw_card *card, int generation,
	324	u64 channels_mask, int channel, int bandwidth,
6fdc0370	325	bool allocate, __be32 buffer[2])
b1bda4cd	326	{
5d9cb7d2 SR	327	u32 channels_hi = channels_mask; /* channels 31...0 */
5d9cb7d2 SR	328	u32 channels_lo = channels_mask >> 32; /* channels 63...32 */
b1bda4cd JFSR	329	int irm_id, ret, c = -EINVAL;
	330
	331	spin_lock_irq(&card->lock);
	332	irm_id = card->irm_node->node_id;
	333	spin_unlock_irq(&card->lock);
	334
	335	if (channels_hi)
	336	c = manage_channel(card, irm_id, generation, channels_hi,
6fdc0370 SR	337	CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI,
6fdc0370 SR	338	allocate, buffer);
b1bda4cd JFSR	339	if (channels_lo && c < 0) {
b1bda4cd JFSR	340	c = manage_channel(card, irm_id, generation, channels_lo,
6fdc0370 SR	341	CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO,
6fdc0370 SR	342	allocate, buffer);
b1bda4cd JFSR	343	if (c >= 0)
	344	c += 32;
	345	}
	346	*channel = c;
	347
5d9cb7d2	348	if (allocate && channels_mask != 0 && c < 0)
b1bda4cd JFSR	349	*bandwidth = 0;
	350
	351	if (*bandwidth == 0)
	352	return;
	353
6fdc0370 SR	354	ret = manage_bandwidth(card, irm_id, generation, *bandwidth,
6fdc0370 SR	355	allocate, buffer);
b1bda4cd JFSR	356	if (ret < 0)
	357	*bandwidth = 0;
	358
cf36df6b CL	359	if (allocate && ret < 0) {
	360	if (c >= 0)
	361	deallocate_channel(card, irm_id, generation, c, buffer);
b1bda4cd JFSR	362	*channel = ret;
	363	}
	364	}