firewire: implement asynchronous stream transmission

Allow userspace and other firewire drivers (fw-ipv4 I'm looking at
you!) to send Asynchronous Transmit Streams as described in 7.8.3 of
release 1.1 of the 1394 Open Host Controller Interface Specification.

Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (tweaks)

1 files changed, 25 insertions, 0 deletions

diff --git a/drivers/firewire/fw-transaction.c b/drivers/firewire/fw-transaction.c
index 76938fe432a0..e3da58991960 100644
--- a/drivers/firewire/fw-transaction.c
+++ b/drivers/firewire/fw-transaction.c
@@ -37,6 +37,10 @@
 #include "fw-topology.h"
 #include "fw-device.h"
 
+#define HEADER_TAG(tag)                 ((tag) << 14)
+#define HEADER_CHANNEL(ch)              ((ch) << 8)
+#define HEADER_SY(sy)                   ((sy) << 0)
+
 #define HEADER_PRI(pri)                 ((pri) << 0)
 #define HEADER_TCODE(tcode)             ((tcode) << 4)
 #define HEADER_RETRY(retry)             ((retry) << 8)
@@ -293,6 +297,27 @@ void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
 }
 EXPORT_SYMBOL(fw_send_request);
 
+void fw_send_stream_packet(struct fw_card *card, struct fw_packet *p,
+                int generation, int speed, int channel, int sy, int tag,
+                void *payload, size_t length, fw_packet_callback_t callback)
+{
+        p->callback = callback;
+        p->header[0] =
+                  HEADER_DATA_LENGTH(length)
+                | HEADER_TAG(tag)
+                | HEADER_CHANNEL(channel)
+                | HEADER_TCODE(TCODE_STREAM_DATA)
+                | HEADER_SY(sy);
+        p->header_length = 4;
+        p->payload = payload;
+        p->payload_length = length;
+        p->speed = speed;
+        p->generation = generation;
+        p->ack = 0;
+
+        card->driver->send_request(card, p);
+}
+
 struct transaction_callback_data {
         struct completion done;
         void *payload;