[PATCH rfc] firewire: add isochronous multichannel reception
From: Stefan Richter
Date: Thu Jul 29 2010 - 11:08:56 EST
This adds the DMA context programming and userspace ABI for multichannel
reception, i.e. for listening on multiple channel numbers by means of a
single DMA context.
The use case is reception of more streams than there are IR DMA units
offered by the link layer. This is already implemented by the older
ohci1394 + ieee1394 + raw1394 stack. And as discussed recently on
linux1394-devel, this feature is occasionally used in practice.
The big drawbacks of this mode are that buffer layout and interrupt
generation necessarily differ from single-channel reception: Headers
and trailers are not stripped from packets, packets are not aligned with
buffer chunks, interrupts are per buffer chunk, not per packet.
These drawbacks also cause a rather hefty code footprint to support this
rarely used OHCI-1394 feature. (367 lines added, among them 94 lines of
added userspace ABI documentation.)
This implementation enforces that a multichannel reception context may
only listen to channels to which no single-channel context on the same
link layer is presently listening to. OHCI-1394 would allow to overlay
single-channel contexts by the multi-channel context, but this would be
a departure from the present first-come-first-served policy of IR
context creation.
The implementation is heavily based on an earlier one by Jay Fenlason.
Thanks Jay.
Signed-off-by: Stefan Richter <stefanr@xxxxxxxxxxxxxxxxx>
---
I intend to implement the libraw1394 backend for this next week.
drivers/firewire/core-cdev.c | 93 ++++++++--
drivers/firewire/core-iso.c | 32 ++-
drivers/firewire/core.h | 2 +
drivers/firewire/ohci.c | 312 +++++++++++++++++++++++++++-------
include/linux/firewire-cdev.h | 281 +++++++++++++++++++++----------
include/linux/firewire.h | 29 ++-
6 files changed, 558 insertions(+), 191 deletions(-)
Index: b/drivers/firewire/core-cdev.c
===================================================================
--- a/drivers/firewire/core-cdev.c
+++ b/drivers/firewire/core-cdev.c
@@ -194,6 +194,11 @@ struct iso_interrupt_event {
struct fw_cdev_event_iso_interrupt interrupt;
};
+struct iso_interrupt_mc_event {
+ struct event event;
+ struct fw_cdev_event_iso_interrupt_mc interrupt;
+};
+
struct iso_resource_event {
struct event event;
struct fw_cdev_event_iso_resource iso_resource;
@@ -416,6 +421,7 @@ union ioctl_arg {
struct fw_cdev_get_cycle_timer2 get_cycle_timer2;
struct fw_cdev_send_phy_packet send_phy_packet;
struct fw_cdev_receive_phy_packets receive_phy_packets;
+ struct fw_cdev_set_iso_channels set_iso_channels;
};
static int ioctl_get_info(struct client *client, union ioctl_arg *arg)
@@ -933,26 +939,54 @@ static void iso_callback(struct fw_iso_c
sizeof(e->interrupt) + header_length, NULL, 0);
}
+static void iso_mc_callback(struct fw_iso_context *context,
+ dma_addr_t completed, void *data)
+{
+ struct client *client = data;
+ struct iso_interrupt_mc_event *e;
+
+ e = kmalloc(sizeof(*e), GFP_ATOMIC);
+ if (e == NULL) {
+ fw_notify("Out of memory when allocating event\n");
+ return;
+ }
+ e->interrupt.type = FW_CDEV_EVENT_ISO_INTERRUPT_MULTICHANNEL;
+ e->interrupt.closure = client->iso_closure;
+ e->interrupt.completed = fw_iso_buffer_lookup(&client->buffer,
+ completed);
+ queue_event(client, &e->event, &e->interrupt,
+ sizeof(e->interrupt), NULL, 0);
+}
+
static int ioctl_create_iso_context(struct client *client, union ioctl_arg *arg)
{
struct fw_cdev_create_iso_context *a = &arg->create_iso_context;
struct fw_iso_context *context;
+ fw_iso_callback_t cb;
BUILD_BUG_ON(FW_CDEV_ISO_CONTEXT_TRANSMIT != FW_ISO_CONTEXT_TRANSMIT ||
- FW_CDEV_ISO_CONTEXT_RECEIVE != FW_ISO_CONTEXT_RECEIVE);
-
- if (a->channel > 63)
- return -EINVAL;
+ FW_CDEV_ISO_CONTEXT_RECEIVE != FW_ISO_CONTEXT_RECEIVE ||
+ FW_CDEV_ISO_CONTEXT_RECEIVE_MULTICHANNEL !=
+ FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL);
switch (a->type) {
- case FW_ISO_CONTEXT_RECEIVE:
- if (a->header_size < 4 || (a->header_size & 3))
+ case FW_ISO_CONTEXT_TRANSMIT:
+ if (a->speed > SCODE_3200 || a->channel > 63)
return -EINVAL;
+
+ cb = iso_callback;
break;
- case FW_ISO_CONTEXT_TRANSMIT:
- if (a->speed > SCODE_3200)
+ case FW_ISO_CONTEXT_RECEIVE:
+ if (a->header_size < 4 || (a->header_size & 3) ||
+ a->channel > 63)
return -EINVAL;
+
+ cb = iso_callback;
+ break;
+
+ case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
+ cb = (fw_iso_callback_t)iso_mc_callback;
break;
default:
@@ -960,8 +994,7 @@ static int ioctl_create_iso_context(stru
}
context = fw_iso_context_create(client->device->card, a->type,
- a->channel, a->speed, a->header_size,
- iso_callback, client);
+ a->channel, a->speed, a->header_size, cb, client);
if (IS_ERR(context))
return PTR_ERR(context);
@@ -981,6 +1014,17 @@ static int ioctl_create_iso_context(stru
return 0;
}
+static int ioctl_set_iso_channels(struct client *client, union ioctl_arg *arg)
+{
+ struct fw_cdev_set_iso_channels *a = &arg->set_iso_channels;
+ struct fw_iso_context *ctx = client->iso_context;
+
+ if (ctx == NULL || a->handle != 0)
+ return -EINVAL;
+
+ return fw_iso_context_set_channels(ctx, &a->channels);
+}
+
/* Macros for decoding the iso packet control header. */
#define GET_PAYLOAD_LENGTH(v) ((v) & 0xffff)
#define GET_INTERRUPT(v) (((v) >> 16) & 0x01)
@@ -994,7 +1038,7 @@ static int ioctl_queue_iso(struct client
struct fw_cdev_queue_iso *a = &arg->queue_iso;
struct fw_cdev_iso_packet __user *p, *end, *next;
struct fw_iso_context *ctx = client->iso_context;
- unsigned long payload, buffer_end, transmit_header_bytes;
+ unsigned long payload, buffer_end, transmit_header_bytes = 0;
u32 control;
int count;
struct {
@@ -1014,7 +1058,6 @@ static int ioctl_queue_iso(struct client
* use the indirect payload, the iso buffer need not be mapped
* and the a->data pointer is ignored.
*/
-
payload = (unsigned long)a->data - client->vm_start;
buffer_end = client->buffer.page_count << PAGE_SHIFT;
if (a->data == 0 || client->buffer.pages == NULL ||
@@ -1023,8 +1066,10 @@ static int ioctl_queue_iso(struct client
buffer_end = 0;
}
- p = (struct fw_cdev_iso_packet __user *)u64_to_uptr(a->packets);
+ if (ctx->type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL && payload & 3)
+ return -EINVAL;
+ p = (struct fw_cdev_iso_packet __user *)u64_to_uptr(a->packets);
if (!access_ok(VERIFY_READ, p, a->size))
return -EFAULT;
@@ -1040,19 +1085,24 @@ static int ioctl_queue_iso(struct client
u.packet.sy = GET_SY(control);
u.packet.header_length = GET_HEADER_LENGTH(control);
- if (ctx->type == FW_ISO_CONTEXT_TRANSMIT) {
- if (u.packet.header_length % 4 != 0)
+ switch (ctx->type) {
+ case FW_ISO_CONTEXT_TRANSMIT:
+ if (u.packet.header_length & 3)
return -EINVAL;
transmit_header_bytes = u.packet.header_length;
- } else {
- /*
- * We require that header_length is a multiple of
- * the fixed header size, ctx->header_size.
- */
+ break;
+
+ case FW_ISO_CONTEXT_RECEIVE:
if (u.packet.header_length == 0 ||
u.packet.header_length % ctx->header_size != 0)
return -EINVAL;
- transmit_header_bytes = 0;
+ break;
+
+ case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
+ if (u.packet.payload_length == 0 ||
+ u.packet.payload_length & 3)
+ return -EINVAL;
+ break;
}
next = (struct fw_cdev_iso_packet __user *)
@@ -1535,6 +1585,7 @@ static int (* const ioctl_handlers[])(st
[0x14] = ioctl_get_cycle_timer2,
[0x15] = ioctl_send_phy_packet,
[0x16] = ioctl_receive_phy_packets,
+ [0x17] = ioctl_set_iso_channels,
};
static int dispatch_ioctl(struct client *client,
Index: b/drivers/firewire/core-iso.c
===================================================================
--- a/drivers/firewire/core-iso.c
+++ b/drivers/firewire/core-iso.c
@@ -118,6 +118,23 @@ void fw_iso_buffer_destroy(struct fw_iso
}
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)
@@ -134,7 +151,7 @@ struct fw_iso_context *fw_iso_context_cr
ctx->channel = channel;
ctx->speed = speed;
ctx->header_size = header_size;
- ctx->callback = callback;
+ ctx->callback.sc = callback;
ctx->callback_data = callback_data;
return ctx;
@@ -143,9 +160,7 @@ EXPORT_SYMBOL(fw_iso_context_create);
void fw_iso_context_destroy(struct fw_iso_context *ctx)
{
- struct fw_card *card = ctx->card;
-
- card->driver->free_iso_context(ctx);
+ ctx->card->driver->free_iso_context(ctx);
}
EXPORT_SYMBOL(fw_iso_context_destroy);
@@ -156,14 +171,17 @@ int fw_iso_context_start(struct fw_iso_c
}
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)
{
- struct fw_card *card = ctx->card;
-
- return card->driver->queue_iso(ctx, packet, buffer, payload);
+ return ctx->card->driver->queue_iso(ctx, packet, buffer, payload);
}
EXPORT_SYMBOL(fw_iso_context_queue);
Index: b/drivers/firewire/core.h
===================================================================
--- a/drivers/firewire/core.h
+++ b/drivers/firewire/core.h
@@ -90,6 +90,8 @@ struct fw_card_driver {
int (*start_iso)(struct fw_iso_context *ctx,
s32 cycle, u32 sync, u32 tags);
+ int (*set_iso_channels)(struct fw_iso_context *ctx, u64 *channels);
+
int (*queue_iso)(struct fw_iso_context *ctx,
struct fw_iso_packet *packet,
struct fw_iso_buffer *buffer,
Index: b/drivers/firewire/ohci.c
===================================================================
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -190,11 +190,13 @@ struct fw_ohci {
struct context at_request_ctx;
struct context at_response_ctx;
- u32 it_context_mask;
+ u32 it_context_mask; /* unoccupied IT contexts */
struct iso_context *it_context_list;
- u64 ir_context_channels;
- u32 ir_context_mask;
+ u64 ir_context_channels; /* unoccupied channels */
+ u32 ir_context_mask; /* unoccupied IR contexts */
struct iso_context *ir_context_list;
+ u64 mc_channels; /* channels in use by the multichannel IR context */
+ bool mc_allocated;
__be32 *config_rom;
dma_addr_t config_rom_bus;
@@ -2202,10 +2204,9 @@ static int handle_ir_packet_per_buffer(s
__le32 *ir_header;
void *p;
- for (pd = d; pd <= last; pd++) {
+ for (pd = d; pd <= last; pd++)
if (pd->transfer_status)
break;
- }
if (pd > last)
/* Descriptor(s) not done yet, stop iteration */
return 0;
@@ -2215,16 +2216,38 @@ static int handle_ir_packet_per_buffer(s
if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
ir_header = (__le32 *) p;
- ctx->base.callback(&ctx->base,
- le32_to_cpu(ir_header[0]) & 0xffff,
- ctx->header_length, ctx->header,
- ctx->base.callback_data);
+ ctx->base.callback.sc(&ctx->base,
+ le32_to_cpu(ir_header[0]) & 0xffff,
+ ctx->header_length, ctx->header,
+ ctx->base.callback_data);
ctx->header_length = 0;
}
return 1;
}
+/* d == last because each descriptor block is only a single descriptor. */
+static int handle_ir_buffer_fill(struct context *context,
+ struct descriptor *d,
+ struct descriptor *last)
+{
+ struct iso_context *ctx =
+ container_of(context, struct iso_context, context);
+
+ if (!last->transfer_status)
+ /* Descriptor(s) not done yet, stop iteration */
+ return 0;
+
+ if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS)
+ ctx->base.callback.mc(&ctx->base,
+ le32_to_cpu(last->data_address) +
+ le16_to_cpu(last->req_count) -
+ le16_to_cpu(last->res_count),
+ ctx->base.callback_data);
+
+ return 1;
+}
+
static int handle_it_packet(struct context *context,
struct descriptor *d,
struct descriptor *last)
@@ -2250,72 +2273,118 @@ static int handle_it_packet(struct conte
ctx->header_length += 4;
}
if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
- ctx->base.callback(&ctx->base, le16_to_cpu(last->res_count),
- ctx->header_length, ctx->header,
- ctx->base.callback_data);
+ ctx->base.callback.sc(&ctx->base, le16_to_cpu(last->res_count),
+ ctx->header_length, ctx->header,
+ ctx->base.callback_data);
ctx->header_length = 0;
}
return 1;
}
+static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
+{
+ u32 hi = channels >> 32, lo = channels;
+
+ reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
+ reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
+ reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
+ reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
+ mmiowb();
+ ohci->mc_channels = channels;
+}
+
static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
int type, int channel, size_t header_size)
{
struct fw_ohci *ohci = fw_ohci(card);
- struct iso_context *ctx, *list;
- descriptor_callback_t callback;
- u64 *channels, dont_care = ~0ULL;
- u32 *mask, regs;
+ struct iso_context *uninitialized_var(ctx);
+ descriptor_callback_t uninitialized_var(callback);
+ u64 *uninitialized_var(channels);
+ u32 *uninitialized_var(mask), uninitialized_var(regs);
unsigned long flags;
- int index, ret = -ENOMEM;
+ int index, ret = -EBUSY;
- if (type == FW_ISO_CONTEXT_TRANSMIT) {
- channels = &dont_care;
- mask = &ohci->it_context_mask;
- list = ohci->it_context_list;
+ spin_lock_irqsave(&ohci->lock, flags);
+
+ switch (type) {
+ case FW_ISO_CONTEXT_TRANSMIT:
+ mask = &ohci->it_context_mask;
callback = handle_it_packet;
- } else {
+ index = ffs(*mask) - 1;
+ if (index >= 0) {
+ *mask &= ~(1 << index);
+ regs = OHCI1394_IsoXmitContextBase(index);
+ ctx = &ohci->it_context_list[index];
+ }
+ break;
+
+ case FW_ISO_CONTEXT_RECEIVE:
channels = &ohci->ir_context_channels;
- mask = &ohci->ir_context_mask;
- list = ohci->ir_context_list;
+ mask = &ohci->ir_context_mask;
callback = handle_ir_packet_per_buffer;
- }
+ index = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
+ if (index >= 0) {
+ *channels &= ~(1ULL << channel);
+ *mask &= ~(1 << index);
+ regs = OHCI1394_IsoRcvContextBase(index);
+ ctx = &ohci->ir_context_list[index];
+ }
+ break;
- spin_lock_irqsave(&ohci->lock, flags);
- index = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
- if (index >= 0) {
- *channels &= ~(1ULL << channel);
- *mask &= ~(1 << index);
+ case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
+ mask = &ohci->ir_context_mask;
+ callback = handle_ir_buffer_fill;
+ index = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
+ if (index >= 0) {
+ ohci->mc_allocated = true;
+ *mask &= ~(1 << index);
+ regs = OHCI1394_IsoRcvContextBase(index);
+ ctx = &ohci->ir_context_list[index];
+ }
+ break;
+
+ default:
+ index = -1;
+ ret = -ENOSYS;
}
+
spin_unlock_irqrestore(&ohci->lock, flags);
if (index < 0)
- return ERR_PTR(-EBUSY);
-
- if (type == FW_ISO_CONTEXT_TRANSMIT)
- regs = OHCI1394_IsoXmitContextBase(index);
- else
- regs = OHCI1394_IsoRcvContextBase(index);
+ return ERR_PTR(ret);
- ctx = &list[index];
memset(ctx, 0, sizeof(*ctx));
ctx->header_length = 0;
ctx->header = (void *) __get_free_page(GFP_KERNEL);
- if (ctx->header == NULL)
+ if (ctx->header == NULL) {
+ ret = -ENOMEM;
goto out;
-
+ }
ret = context_init(&ctx->context, ohci, regs, callback);
if (ret < 0)
goto out_with_header;
+ if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL)
+ set_multichannel_mask(ohci, 0);
+
return &ctx->base;
out_with_header:
free_page((unsigned long)ctx->header);
out:
spin_lock_irqsave(&ohci->lock, flags);
- *channels |= 1ULL << channel;
+
+ switch (type) {
+ case FW_ISO_CONTEXT_RECEIVE:
+ *channels |= 1ULL << channel;
+ break;
+
+ case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
+ ohci->mc_allocated = false;
+ break;
+ }
*mask |= 1 << index;
+
spin_unlock_irqrestore(&ohci->lock, flags);
return ERR_PTR(ret);
@@ -2326,10 +2395,11 @@ static int ohci_start_iso(struct fw_iso_
{
struct iso_context *ctx = container_of(base, struct iso_context, base);
struct fw_ohci *ohci = ctx->context.ohci;
- u32 control, match;
+ u32 control = IR_CONTEXT_ISOCH_HEADER, match;
int index;
- if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
+ switch (ctx->base.type) {
+ case FW_ISO_CONTEXT_TRANSMIT:
index = ctx - ohci->it_context_list;
match = 0;
if (cycle >= 0)
@@ -2339,9 +2409,13 @@ static int ohci_start_iso(struct fw_iso_
reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
context_run(&ctx->context, match);
- } else {
+ break;
+
+ case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
+ control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
+ /* fall through */
+ case FW_ISO_CONTEXT_RECEIVE:
index = ctx - ohci->ir_context_list;
- control = IR_CONTEXT_ISOCH_HEADER;
match = (tags << 28) | (sync << 8) | ctx->base.channel;
if (cycle >= 0) {
match |= (cycle & 0x07fff) << 12;
@@ -2352,6 +2426,7 @@ static int ohci_start_iso(struct fw_iso_
reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
context_run(&ctx->context, control);
+ break;
}
return 0;
@@ -2363,12 +2438,17 @@ static int ohci_stop_iso(struct fw_iso_c
struct iso_context *ctx = container_of(base, struct iso_context, base);
int index;
- if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
+ switch (ctx->base.type) {
+ case FW_ISO_CONTEXT_TRANSMIT:
index = ctx - ohci->it_context_list;
reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
- } else {
+ break;
+
+ case FW_ISO_CONTEXT_RECEIVE:
+ case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
index = ctx - ohci->ir_context_list;
reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
+ break;
}
flush_writes(ohci);
context_stop(&ctx->context);
@@ -2389,22 +2469,64 @@ static void ohci_free_iso_context(struct
spin_lock_irqsave(&ohci->lock, flags);
- if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
+ switch (base->type) {
+ case FW_ISO_CONTEXT_TRANSMIT:
index = ctx - ohci->it_context_list;
ohci->it_context_mask |= 1 << index;
- } else {
+ break;
+
+ case FW_ISO_CONTEXT_RECEIVE:
index = ctx - ohci->ir_context_list;
ohci->ir_context_mask |= 1 << index;
ohci->ir_context_channels |= 1ULL << base->channel;
+ break;
+
+ case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
+ index = ctx - ohci->ir_context_list;
+ ohci->ir_context_mask |= 1 << index;
+ ohci->ir_context_channels |= ohci->mc_channels;
+ ohci->mc_channels = 0;
+ ohci->mc_allocated = false;
+ break;
}
spin_unlock_irqrestore(&ohci->lock, flags);
}
-static int ohci_queue_iso_transmit(struct fw_iso_context *base,
- struct fw_iso_packet *packet,
- struct fw_iso_buffer *buffer,
- unsigned long payload)
+static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
+{
+ struct fw_ohci *ohci = fw_ohci(base->card);
+ unsigned long flags;
+ int ret;
+
+ switch (base->type) {
+ case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
+
+ spin_lock_irqsave(&ohci->lock, flags);
+
+ /* Don't allow multichannel to grab other contexts' channels. */
+ if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
+ *channels = ohci->ir_context_channels;
+ ret = -EBUSY;
+ } else {
+ set_multichannel_mask(ohci, *channels);
+ ret = 0;
+ }
+
+ spin_unlock_irqrestore(&ohci->lock, flags);
+
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+static int queue_iso_transmit(struct fw_iso_context *base,
+ struct fw_iso_packet *packet,
+ struct fw_iso_buffer *buffer,
+ unsigned long payload)
{
struct iso_context *ctx = container_of(base, struct iso_context, base);
struct descriptor *d, *last, *pd;
@@ -2502,14 +2624,13 @@ static int ohci_queue_iso_transmit(struc
return 0;
}
-static int ohci_queue_iso_receive_packet_per_buffer(struct fw_iso_context *base,
- struct fw_iso_packet *packet,
- struct fw_iso_buffer *buffer,
- unsigned long payload)
+static int queue_iso_packet_per_buffer(struct fw_iso_context *base,
+ struct fw_iso_packet *packet,
+ struct fw_iso_buffer *buffer,
+ unsigned long payload)
{
struct iso_context *ctx = container_of(base, struct iso_context, base);
struct descriptor *d, *pd;
- struct fw_iso_packet *p = packet;
dma_addr_t d_bus, page_bus;
u32 z, header_z, rest;
int i, j, length;
@@ -2519,14 +2640,14 @@ static int ohci_queue_iso_receive_packet
* The OHCI controller puts the isochronous header and trailer in the
* buffer, so we need at least 8 bytes.
*/
- packet_count = p->header_length / ctx->base.header_size;
+ packet_count = packet->header_length / ctx->base.header_size;
header_size = max(ctx->base.header_size, (size_t)8);
/* Get header size in number of descriptors. */
header_z = DIV_ROUND_UP(header_size, sizeof(*d));
page = payload >> PAGE_SHIFT;
offset = payload & ~PAGE_MASK;
- payload_per_buffer = p->payload_length / packet_count;
+ payload_per_buffer = packet->payload_length / packet_count;
for (i = 0; i < packet_count; i++) {
/* d points to the header descriptor */
@@ -2538,7 +2659,7 @@ static int ohci_queue_iso_receive_packet
d->control = cpu_to_le16(DESCRIPTOR_STATUS |
DESCRIPTOR_INPUT_MORE);
- if (p->skip && i == 0)
+ if (packet->skip && i == 0)
d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
d->req_count = cpu_to_le16(header_size);
d->res_count = d->req_count;
@@ -2571,7 +2692,7 @@ static int ohci_queue_iso_receive_packet
pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
DESCRIPTOR_INPUT_LAST |
DESCRIPTOR_BRANCH_ALWAYS);
- if (p->interrupt && i == packet_count - 1)
+ if (packet->interrupt && i == packet_count - 1)
pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
context_append(&ctx->context, d, z, header_z);
@@ -2580,6 +2701,59 @@ static int ohci_queue_iso_receive_packet
return 0;
}
+static int queue_iso_buffer_fill(struct fw_iso_context *base,
+ struct fw_iso_packet *packet,
+ struct fw_iso_buffer *buffer,
+ unsigned long payload)
+{
+ struct iso_context *ctx = container_of(base, struct iso_context, base);
+ struct descriptor *d;
+ dma_addr_t d_bus, page_bus;
+ int page, offset, rest, z, i, length;
+
+ page = payload >> PAGE_SHIFT;
+ offset = payload & ~PAGE_MASK;
+ rest = packet->payload_length;
+
+ /* We need one descriptor for each page in the buffer. */
+ z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
+
+ if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
+ return -EFAULT;
+
+ for (i = 0; i < z; i++) {
+ d = context_get_descriptors(&ctx->context, 1, &d_bus);
+ if (d == NULL)
+ return -ENOMEM;
+
+ d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
+ DESCRIPTOR_BRANCH_ALWAYS);
+ if (packet->skip && i == 0)
+ d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
+ if (packet->interrupt && i == z - 1)
+ d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
+
+ if (offset + rest < PAGE_SIZE)
+ length = rest;
+ else
+ length = PAGE_SIZE - offset;
+ d->req_count = cpu_to_le16(length);
+ d->res_count = d->req_count;
+ d->transfer_status = 0;
+
+ page_bus = page_private(buffer->pages[page]);
+ d->data_address = cpu_to_le32(page_bus + offset);
+
+ rest -= length;
+ offset = 0;
+ page++;
+
+ context_append(&ctx->context, d, 1, 0);
+ }
+
+ return 0;
+}
+
static int ohci_queue_iso(struct fw_iso_context *base,
struct fw_iso_packet *packet,
struct fw_iso_buffer *buffer,
@@ -2587,14 +2761,17 @@ static int ohci_queue_iso(struct fw_iso_
{
struct iso_context *ctx = container_of(base, struct iso_context, base);
unsigned long flags;
- int ret;
+ int ret = -ENOSYS;
spin_lock_irqsave(&ctx->context.ohci->lock, flags);
- if (base->type == FW_ISO_CONTEXT_TRANSMIT)
- ret = ohci_queue_iso_transmit(base, packet, buffer, payload);
- else
- ret = ohci_queue_iso_receive_packet_per_buffer(base, packet,
- buffer, payload);
+ switch (base->type) {
+ case FW_ISO_CONTEXT_TRANSMIT:
+ ret = queue_iso_transmit(base, packet, buffer, payload);
+ case FW_ISO_CONTEXT_RECEIVE:
+ ret = queue_iso_packet_per_buffer(base, packet, buffer, payload);
+ case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
+ ret = queue_iso_buffer_fill(base, packet, buffer, payload);
+ }
spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
return ret;
@@ -2614,6 +2791,7 @@ static const struct fw_card_driver ohci_
.allocate_iso_context = ohci_allocate_iso_context,
.free_iso_context = ohci_free_iso_context,
+ .set_iso_channels = ohci_set_iso_channels,
.queue_iso = ohci_queue_iso,
.start_iso = ohci_start_iso,
.stop_iso = ohci_stop_iso,
Index: b/include/linux/firewire-cdev.h
===================================================================
--- a/include/linux/firewire-cdev.h
+++ b/include/linux/firewire-cdev.h
@@ -30,17 +30,18 @@
#include <linux/types.h>
#include <linux/firewire-constants.h>
-#define FW_CDEV_EVENT_BUS_RESET 0x00
-#define FW_CDEV_EVENT_RESPONSE 0x01
-#define FW_CDEV_EVENT_REQUEST 0x02
-#define FW_CDEV_EVENT_ISO_INTERRUPT 0x03
-#define FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED 0x04
-#define FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED 0x05
+#define FW_CDEV_EVENT_BUS_RESET 0x00
+#define FW_CDEV_EVENT_RESPONSE 0x01
+#define FW_CDEV_EVENT_REQUEST 0x02
+#define FW_CDEV_EVENT_ISO_INTERRUPT 0x03
+#define FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED 0x04
+#define FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED 0x05
/* available since kernel version 2.6.36 */
-#define FW_CDEV_EVENT_REQUEST2 0x06
-#define FW_CDEV_EVENT_PHY_PACKET_SENT 0x07
-#define FW_CDEV_EVENT_PHY_PACKET_RECEIVED 0x08
+#define FW_CDEV_EVENT_REQUEST2 0x06
+#define FW_CDEV_EVENT_PHY_PACKET_SENT 0x07
+#define FW_CDEV_EVENT_PHY_PACKET_RECEIVED 0x08
+#define FW_CDEV_EVENT_ISO_INTERRUPT_MULTICHANNEL 0x09
/**
* struct fw_cdev_event_common - Common part of all fw_cdev_event_ types
@@ -223,35 +224,41 @@ struct fw_cdev_event_request2 {
* This event is sent when the controller has completed an &fw_cdev_iso_packet
* with the %FW_CDEV_ISO_INTERRUPT bit set.
*
- * Isochronous transmit events:
+ * Isochronous transmit events (context type %FW_CDEV_ISO_CONTEXT_TRANSMIT):
*
- * In version 1 of the ABI, &header_length is 0. In version 3 and some
- * implementations of version 2 of the ABI, &header_length is a multiple of 4
- * and &header contains timestamps of all packets up until the interrupt packet.
- * The format of the timestamps is as described below for isochronous reception.
+ * In version 3 and some implementations of version 2 of the ABI, &header_length
+ * is a multiple of 4 and &header contains timestamps of all packets up until
+ * the interrupt packet. The format of the timestamps is as described below for
+ * isochronous reception. In version 1 of the ABI, &header_length was 0.
*
- * Isochronous receive events:
+ * Isochronous receive events (context type %FW_CDEV_ISO_CONTEXT_RECEIVE):
*
* The headers stripped of all packets up until and including the interrupt
* packet are returned in the @header field. The amount of header data per
* packet is as specified at iso context creation by
* &fw_cdev_create_iso_context.header_size.
*
- * In version 1 of this ABI, header data consisted of the 1394 isochronous
- * packet header, followed by quadlets from the packet payload if
- * &fw_cdev_create_iso_context.header_size > 4.
- *
- * In version 2 of this ABI, header data consist of the 1394 isochronous
- * packet header, followed by a timestamp quadlet if
- * &fw_cdev_create_iso_context.header_size > 4, followed by quadlets from the
- * packet payload if &fw_cdev_create_iso_context.header_size > 8.
+ * Hence, _interrupt.header_length / _context.header_size is the number of
+ * packets received in this interrupt event. The client can now iterate
+ * through the mmap()'ed DMA buffer according to this number of packets and
+ * to the buffer sizes as the client specified in &fw_cdev_queue_iso.
+ *
+ * Since version 2 of this ABI, the portion for each packet in _interrupt.header
+ * consists of the 1394 isochronous packet header, followed by a timestamp
+ * quadlet if &fw_cdev_create_iso_context.header_size > 4, followed by quadlets
+ * from the packet payload if &fw_cdev_create_iso_context.header_size > 8.
+ *
+ * Format of 1394 iso packet header: 16 bits data_length, 2 bits tag, 6 bits
+ * channel, 4 bits tcode, 4 bits sy, in big endian byte order.
+ * data_length is the actual received size of the packet without the four
+ * 1394 iso packet header bytes.
*
- * Behaviour of ver. 1 of this ABI is no longer available since ABI ver. 2.
+ * Format of timestamp: 16 bits invalid, 3 bits cycleSeconds, 13 bits
+ * cycleCount, in big endian byte order.
*
- * Format of 1394 iso packet header: 16 bits len, 2 bits tag, 6 bits channel,
- * 4 bits tcode, 4 bits sy, in big endian byte order. Format of timestamp:
- * 16 bits invalid, 3 bits cycleSeconds, 13 bits cycleCount, in big endian byte
- * order.
+ * In version 1 of the ABI, no timestamp quadlet was inserted; instead, payload
+ * data followed directly after the 1394 is header if header_size > 4.
+ * Behaviour of ver. 1 of this ABI is no longer available since ABI ver. 2.
*/
struct fw_cdev_event_iso_interrupt {
__u64 closure;
@@ -262,6 +269,43 @@ struct fw_cdev_event_iso_interrupt {
};
/**
+ * struct fw_cdev_event_iso_interrupt_mc - An iso buffer chunk was completed
+ * @closure: See &fw_cdev_event_common;
+ * set by %FW_CDEV_CREATE_ISO_CONTEXT ioctl
+ * @type: %FW_CDEV_EVENT_ISO_INTERRUPT_MULTICHANNEL
+ * @completed: Offset into the receive buffer; data before this offest is valid
+ *
+ * This event is sent in multichannel contexts (context type
+ * %FW_CDEV_ISO_CONTEXT_RECEIVE_MULTICHANNEL) for &fw_cdev_iso_packet buffer
+ * chunks that have the %FW_CDEV_ISO_INTERRUPT bit set. Whether this happens
+ * when a packet is completed and/or when a buffer chunk is completed depends
+ * on the hardware implementation.
+ *
+ * The buffer is continuously filled with the following data, per packet:
+ * - the 1394 iso packet header as described at &fw_cdev_event_iso_interrupt,
+ * but in little endian byte order,
+ * - packet payload (as many bytes as specified in the data_length field of
+ * the 1394 iso packet header) in big endian byte order,
+ * - 0...3 padding bytes as needed to align the following trailer quadlet,
+ * - trailer quadlet, containing the reception timestamp as described at
+ * &fw_cdev_event_iso_interrupt, but in little endian byte order.
+ *
+ * Hence the per-packet size is data_length (rounded up to a multiple of 4) + 8.
+ * When processing the data, stop before a packet that would cross the
+ * @completed offset.
+ *
+ * A packet near the end of a buffer chunk will typically spill over into the
+ * next queued buffer chunk. It is the responsibility of the client to check
+ * for this condition, assemble a broken-up packet from its parts, and not to
+ * re-queue any buffer chunks in which as yet unread packet parts reside.
+ */
+struct fw_cdev_event_iso_interrupt_mc {
+ __u64 closure;
+ __u32 type;
+ __u32 completed;
+};
+
+/**
* struct fw_cdev_event_iso_resource - Iso resources were allocated or freed
* @closure: See &fw_cdev_event_common;
* set by %FW_CDEV_IOC_(DE)ALLOCATE_ISO_RESOURCE(_ONCE) ioctl
@@ -316,16 +360,18 @@ struct fw_cdev_event_phy_packet {
/**
* union fw_cdev_event - Convenience union of fw_cdev_event_ types
- * @common: Valid for all types
- * @bus_reset: Valid if @common.type == %FW_CDEV_EVENT_BUS_RESET
- * @response: Valid if @common.type == %FW_CDEV_EVENT_RESPONSE
- * @request: Valid if @common.type == %FW_CDEV_EVENT_REQUEST
- * @request2: Valid if @common.type == %FW_CDEV_EVENT_REQUEST2
- * @iso_interrupt: Valid if @common.type == %FW_CDEV_EVENT_ISO_INTERRUPT
- * @iso_resource: Valid if @common.type ==
+ * @common: Valid for all types
+ * @bus_reset: Valid if @common.type == %FW_CDEV_EVENT_BUS_RESET
+ * @response: Valid if @common.type == %FW_CDEV_EVENT_RESPONSE
+ * @request: Valid if @common.type == %FW_CDEV_EVENT_REQUEST
+ * @request2: Valid if @common.type == %FW_CDEV_EVENT_REQUEST2
+ * @iso_interrupt: Valid if @common.type == %FW_CDEV_EVENT_ISO_INTERRUPT
+ * @iso_interrupt_mc: Valid if @common.type ==
+ * %FW_CDEV_EVENT_ISO_INTERRUPT_MULTICHANNEL
+ * @iso_resource: Valid if @common.type ==
* %FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED or
* %FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED
- * @phy_packet: Valid if @common.type ==
+ * @phy_packet: Valid if @common.type ==
* %FW_CDEV_EVENT_PHY_PACKET_SENT or
* %FW_CDEV_EVENT_PHY_PACKET_RECEIVED
*
@@ -342,10 +388,11 @@ union fw_cdev_event {
struct fw_cdev_event_bus_reset bus_reset;
struct fw_cdev_event_response response;
struct fw_cdev_event_request request;
- struct fw_cdev_event_request2 request2; /* added in 2.6.36 */
+ struct fw_cdev_event_request2 request2; /* added in 2.6.36 */
struct fw_cdev_event_iso_interrupt iso_interrupt;
- struct fw_cdev_event_iso_resource iso_resource; /* added in 2.6.30 */
- struct fw_cdev_event_phy_packet phy_packet; /* added in 2.6.36 */
+ struct fw_cdev_event_iso_interrupt_mc iso_interrupt_mc; /* added in 2.6.36 */
+ struct fw_cdev_event_iso_resource iso_resource; /* added in 2.6.30 */
+ struct fw_cdev_event_phy_packet phy_packet; /* added in 2.6.36 */
};
/* available since kernel version 2.6.22 */
@@ -380,6 +427,7 @@ union fw_cdev_event {
/* available since kernel version 2.6.36 */
#define FW_CDEV_IOC_SEND_PHY_PACKET _IOWR('#', 0x15, struct fw_cdev_send_phy_packet)
#define FW_CDEV_IOC_RECEIVE_PHY_PACKETS _IOW('#', 0x16, struct fw_cdev_receive_phy_packets)
+#define FW_CDEV_IOC_SET_ISO_CHANNELS _IOW('#', 0x17, struct fw_cdev_set_iso_channels)
/*
* ABI version history
@@ -396,10 +444,13 @@ union fw_cdev_event {
* - shared use and auto-response for FCP registers
* 3 (2.6.34) - made &fw_cdev_get_cycle_timer reliable
* - added %FW_CDEV_IOC_GET_CYCLE_TIMER2
- * 4 (2.6.36) - added %FW_CDEV_EVENT_REQUEST2, %FW_CDEV_EVENT_PHY_PACKET_*
+ * 4 (2.6.36) - added %FW_CDEV_EVENT_REQUEST2, %FW_CDEV_EVENT_PHY_PACKET_*,
+ * and &fw_cdev_allocate.region_end
* - implemented &fw_cdev_event_bus_reset.bm_node_id
* - added %FW_CDEV_IOC_SEND_PHY_PACKET, _RECEIVE_PHY_PACKETS
- * - added &fw_cdev_allocate.region_end
+ * - added %FW_CDEV_EVENT_ISO_INTERRUPT_MULTICHANNEL,
+ * %FW_CDEV_ISO_CONTEXT_RECEIVE_MULTICHANNEL, and
+ * %FW_CDEV_IOC_SET_ISO_CHANNELS
*/
#define FW_CDEV_VERSION 3 /* Meaningless; don't use this macro. */
@@ -602,34 +653,43 @@ struct fw_cdev_remove_descriptor {
__u32 handle;
};
-#define FW_CDEV_ISO_CONTEXT_TRANSMIT 0
-#define FW_CDEV_ISO_CONTEXT_RECEIVE 1
+#define FW_CDEV_ISO_CONTEXT_TRANSMIT 0
+#define FW_CDEV_ISO_CONTEXT_RECEIVE 1
+#define FW_CDEV_ISO_CONTEXT_RECEIVE_MULTICHANNEL 2 /* added in 2.6.36 */
/**
- * struct fw_cdev_create_iso_context - Create a context for isochronous IO
- * @type: %FW_CDEV_ISO_CONTEXT_TRANSMIT or %FW_CDEV_ISO_CONTEXT_RECEIVE
- * @header_size: Header size to strip for receive contexts
- * @channel: Channel to bind to
- * @speed: Speed for transmit contexts
- * @closure: To be returned in &fw_cdev_event_iso_interrupt
+ * struct fw_cdev_create_iso_context - Create a context for isochronous I/O
+ * @type: %FW_CDEV_ISO_CONTEXT_TRANSMIT or %FW_CDEV_ISO_CONTEXT_RECEIVE or
+ * %FW_CDEV_ISO_CONTEXT_RECEIVE_MULTICHANNEL
+ * @header_size: Header size to strip in single-channel reception
+ * @channel: Channel to bind to in single-channel reception or transmission
+ * @speed: Transmission speed
+ * @closure: To be returned in &fw_cdev_event_iso_interrupt or
+ * &fw_cdev_event_iso_interrupt_multichannel
* @handle: Handle to context, written back by kernel
*
* Prior to sending or receiving isochronous I/O, a context must be created.
* The context records information about the transmit or receive configuration
* and typically maps to an underlying hardware resource. A context is set up
* for either sending or receiving. It is bound to a specific isochronous
- * channel.
+ * @channel.
*
- * If a context was successfully created, the kernel writes back a handle to the
- * context, which must be passed in for subsequent operations on that context.
+ * In case of multichannel reception, @header_size and @channel are ignored
+ * and the channels are selected by %FW_CDEV_IOC_SET_ISO_CHANNELS.
*
- * For receive contexts, @header_size must be at least 4 and must be a multiple
- * of 4.
+ * For %FW_CDEV_ISO_CONTEXT_RECEIVE contexts, @header_size must be at least 4
+ * and must be a multiple of 4. It is ignored in other context types.
*
- * Note that the effect of a @header_size > 4 depends on
- * &fw_cdev_get_info.version, as documented at &fw_cdev_event_iso_interrupt.
+ * @speed is ignored in receive context types.
+ *
+ * If a context was successfully created, the kernel writes back a handle to the
+ * context, which must be passed in for subsequent operations on that context.
*
+ * Limitations:
* No more than one iso context can be created per fd.
+ * The total number of contexts that all userspace and kernelspace drivers can
+ * create on a card at a time is a hardware limit, typically 4 or 8 contexts per
+ * direction, and of them at most one multichannel receive context.
*/
struct fw_cdev_create_iso_context {
__u32 type;
@@ -640,6 +700,22 @@ struct fw_cdev_create_iso_context {
__u32 handle;
};
+/**
+ * struct fw_cdev_set_iso_channels - Select channels in multichannel reception
+ * @channels: Bitmask of channels to listen to
+ * @handle: Handle of the mutichannel receive context
+ *
+ * @channels is the bitwise or of 1ULL << n for each channel n to listen to.
+ *
+ * The ioctl fails with errno %EBUSY if there is already another receive context
+ * on a channel in @channels. In that case, the bitmask of all unoccupied
+ * channels is returned in @channels.
+ */
+struct fw_cdev_set_iso_channels {
+ __u64 channels;
+ __u32 handle;
+};
+
#define FW_CDEV_ISO_PAYLOAD_LENGTH(v) (v)
#define FW_CDEV_ISO_INTERRUPT (1 << 16)
#define FW_CDEV_ISO_SKIP (1 << 17)
@@ -650,42 +726,72 @@ struct fw_cdev_create_iso_context {
/**
* struct fw_cdev_iso_packet - Isochronous packet
- * @control: Contains the header length (8 uppermost bits), the sy field
- * (4 bits), the tag field (2 bits), a sync flag (1 bit),
- * a skip flag (1 bit), an interrupt flag (1 bit), and the
+ * @control: Contains the header length (8 uppermost bits),
+ * the sy field (4 bits), the tag field (2 bits), a sync flag
+ * or a skip flag (1 bit), an interrupt flag (1 bit), and the
* payload length (16 lowermost bits)
- * @header: Header and payload
+ * @header: Header and payload in case of a transmit context.
*
* &struct fw_cdev_iso_packet is used to describe isochronous packet queues.
- *
* Use the FW_CDEV_ISO_ macros to fill in @control.
+ * The @header array is empty in case of receive contexts.
+ *
+ * Context type %FW_CDEV_ISO_CONTEXT_TRANSMIT:
+ *
+ * @control.HEADER_LENGTH must be a multiple of 4. It specifies the numbers of
+ * bytes in @header that will be prepended to the packet's payload. These bytes
+ * are copied into the kernel and will not be accessed after the ioctl has
+ * returned.
+ *
+ * The @control.SY and TAG fields are copied to the iso packet header. These
+ * fields are specified by IEEE 1394a and IEC 61883-1.
+ *
+ * The @control.SKIP flag specifies that no packet is to be sent in a frame.
+ * When using this, all other fields except @control.INTERRUPT must be zero.
+ *
+ * When a packet with the @control.INTERRUPT flag set has been completed, an
+ * &fw_cdev_event_iso_interrupt event will be sent.
*
- * For transmit packets, the header length must be a multiple of 4 and specifies
- * the numbers of bytes in @header that will be prepended to the packet's
- * payload; these bytes are copied into the kernel and will not be accessed
- * after the ioctl has returned. The sy and tag fields are copied to the iso
- * packet header (these fields are specified by IEEE 1394a and IEC 61883-1).
- * The skip flag specifies that no packet is to be sent in a frame; when using
- * this, all other fields except the interrupt flag must be zero.
- *
- * For receive packets, the header length must be a multiple of the context's
- * header size; if the header length is larger than the context's header size,
- * multiple packets are queued for this entry. The sy and tag fields are
- * ignored. If the sync flag is set, the context drops all packets until
- * a packet with a matching sy field is received (the sync value to wait for is
- * specified in the &fw_cdev_start_iso structure). The payload length defines
- * how many payload bytes can be received for one packet (in addition to payload
- * quadlets that have been defined as headers and are stripped and returned in
- * the &fw_cdev_event_iso_interrupt structure). If more bytes are received, the
- * additional bytes are dropped. If less bytes are received, the remaining
- * bytes in this part of the payload buffer will not be written to, not even by
- * the next packet, i.e., packets received in consecutive frames will not
- * necessarily be consecutive in memory. If an entry has queued multiple
- * packets, the payload length is divided equally among them.
+ * Context type %FW_CDEV_ISO_CONTEXT_RECEIVE:
*
- * When a packet with the interrupt flag set has been completed, the
+ * @control.HEADER_LENGTH must be a multiple of the context's header_size.
+ * If the HEADER_LENGTH is larger than the context's header_size, multiple
+ * packets are queued for this entry.
+ *
+ * The @control.SY and TAG fields are ignored.
+ *
+ * If the @control.SYNC flag is set, the context drops all packets until a
+ * packet with a sy field is received which matches &fw_cdev_start_iso.sync.
+ *
+ * @control.PAYLOAD_LENGTH defines how many payload bytes can be received for
+ * one packet (in addition to payload quadlets that have been defined as headers
+ * and are stripped and returned in the &fw_cdev_event_iso_interrupt structure).
+ * If more bytes are received, the additional bytes are dropped. If less bytes
+ * are received, the remaining bytes in this part of the payload buffer will not
+ * be written to, not even by the next packet. I.e., packets received in
+ * consecutive frames will not necessarily be consecutive in memory. If an
+ * entry has queued multiple packets, the PAYLOAD_LENGTH is divided equally
+ * among them.
+ *
+ * When a packet with the @control.INTERRUPT flag set has been completed, an
* &fw_cdev_event_iso_interrupt event will be sent. An entry that has queued
* multiple receive packets is completed when its last packet is completed.
+ *
+ * Context type %FW_CDEV_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
+ *
+ * Here, &fw_cdev_iso_packet would be more aptly named _iso_buffer_chunk since
+ * it specifies a chunk of the mmap()'ed buffer, while the number and alignment
+ * of packets to be placed into the buffer chunk is not known beforehand.
+ *
+ * @control.PAYLOAD_LENGTH is the size of the buffer chunk and specifies room
+ * for header, payload, padding, and trailer bytes of one or more packets.
+ * It must be a multiple of 4.
+ *
+ * @control.HEADER_LENGTH, TAG and SY are ignored. SYNC is treated as described
+ * for single-channel reception.
+ *
+ * When a buffer chunk with the @control.INTERRUPT flag set has been filled
+ * entirely, an &fw_cdev_event_iso_interrupt_mc event will be sent.
*/
struct fw_cdev_iso_packet {
__u32 control;
@@ -694,9 +800,9 @@ struct fw_cdev_iso_packet {
/**
* struct fw_cdev_queue_iso - Queue isochronous packets for I/O
- * @packets: Userspace pointer to packet data
+ * @packets: Userspace pointer to an array of &fw_cdev_iso_packet
* @data: Pointer into mmap()'ed payload buffer
- * @size: Size of packet data in bytes
+ * @size: Size of the @packets array, in bytes
* @handle: Isochronous context handle
*
* Queue a number of isochronous packets for reception or transmission.
@@ -709,6 +815,9 @@ struct fw_cdev_iso_packet {
* The kernel may or may not queue all packets, but will write back updated
* values of the @packets, @data and @size fields, so the ioctl can be
* resubmitted easily.
+ *
+ * In case of a multichannel receive context, @data must be quadlet-aligned
+ * relative to the buffer start.
*/
struct fw_cdev_queue_iso {
__u64 packets;
Index: b/include/linux/firewire.h
===================================================================
--- a/include/linux/firewire.h
+++ b/include/linux/firewire.h
@@ -372,17 +372,19 @@ void fw_core_remove_descriptor(struct fw
* scatter-gather streaming (e.g. assembling video frame automatically).
*/
struct fw_iso_packet {
- u16 payload_length; /* Length of indirect payload. */
- u32 interrupt:1; /* Generate interrupt on this packet */
- u32 skip:1; /* Set to not send packet at all. */
- u32 tag:2;
- u32 sy:4;
- u32 header_length:8; /* Length of immediate header. */
- u32 header[0];
+ u16 payload_length; /* Length of indirect payload */
+ u32 interrupt:1; /* Generate interrupt on this packet */
+ u32 skip:1; /* tx: Set to not send packet at all */
+ /* rx: Sync bit, wait for matching sy */
+ u32 tag:2; /* tx: Tag in packet header */
+ u32 sy:4; /* tx: Sy in packet header */
+ u32 header_length:8; /* Length of immediate header */
+ u32 header[0]; /* tx: Top of 1394 isoch. data_block */
};
-#define FW_ISO_CONTEXT_TRANSMIT 0
-#define FW_ISO_CONTEXT_RECEIVE 1
+#define FW_ISO_CONTEXT_TRANSMIT 0
+#define FW_ISO_CONTEXT_RECEIVE 1
+#define FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL 2
#define FW_ISO_CONTEXT_MATCH_TAG0 1
#define FW_ISO_CONTEXT_MATCH_TAG1 2
@@ -406,24 +408,31 @@ struct fw_iso_buffer {
int fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card,
int page_count, enum dma_data_direction direction);
void fw_iso_buffer_destroy(struct fw_iso_buffer *buffer, struct fw_card *card);
+size_t fw_iso_buffer_lookup(struct fw_iso_buffer *buffer, dma_addr_t completed);
struct fw_iso_context;
typedef void (*fw_iso_callback_t)(struct fw_iso_context *context,
u32 cycle, size_t header_length,
void *header, void *data);
+typedef void (*fw_iso_mc_callback_t)(struct fw_iso_context *context,
+ dma_addr_t completed, void *data);
struct fw_iso_context {
struct fw_card *card;
int type;
int channel;
int speed;
size_t header_size;
- fw_iso_callback_t callback;
+ union {
+ fw_iso_callback_t sc;
+ fw_iso_mc_callback_t mc;
+ } callback;
void *callback_data;
};
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);
+int fw_iso_context_set_channels(struct fw_iso_context *ctx, u64 *channels);
int fw_iso_context_queue(struct fw_iso_context *ctx,
struct fw_iso_packet *packet,
struct fw_iso_buffer *buffer,
--
Stefan Richter
-=====-==-=- -=== ===-=
http://arcgraph.de/sr/
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