lkml.org 
[lkml]   [2009]   [Nov]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 2/6] firedtv: packet requeuing is likely to succeed
Packet DMA buffers are queued either initially all at once (then, a
queueing failure will cause firedtv to release the DMA context as a
whole) or subsequently one by one as they recycled after use (then a
failure is extremely unlikely). Therefore we can be a little less
cautious when counting at which packet buffer to set the interrupt flag.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
---
drivers/media/dvb/firewire/firedtv-fw.c | 13 ++++---------
1 file changed, 4 insertions(+), 9 deletions(-)

Index: linux-2.6.32-rc7/drivers/media/dvb/firewire/firedtv-fw.c
===================================================================
--- linux-2.6.32-rc7.orig/drivers/media/dvb/firewire/firedtv-fw.c
+++ linux-2.6.32-rc7/drivers/media/dvb/firewire/firedtv-fw.c
@@ -79,19 +79,14 @@ struct firedtv_receive_context {
static int queue_iso(struct firedtv_receive_context *ctx, int index)
{
struct fw_iso_packet p;
- int err;

p.payload_length = MAX_PACKET_SIZE;
- p.interrupt = !(ctx->interrupt_packet & (IRQ_INTERVAL - 1));
+ p.interrupt = !(++ctx->interrupt_packet & (IRQ_INTERVAL - 1));
p.skip = 0;
p.header_length = ISO_HEADER_SIZE;

- err = fw_iso_context_queue(ctx->context, &p, &ctx->buffer,
- index * MAX_PACKET_SIZE);
- if (!err)
- ctx->interrupt_packet++;
-
- return err;
+ return fw_iso_context_queue(ctx->context, &p, &ctx->buffer,
+ index * MAX_PACKET_SIZE);
}

static void handle_iso(struct fw_iso_context *context, u32 cycle,
@@ -150,7 +145,7 @@ static int start_iso(struct firedtv *fdt
if (err)
goto fail_context_destroy;

- ctx->interrupt_packet = 1;
+ ctx->interrupt_packet = 0;
ctx->current_packet = 0;

for (i = 0; i < N_PAGES; i++)
--
Stefan Richter
-=====-==--= =-== =--=-
http://arcgraph.de/sr/


\
 
 \ /
  Last update: 2009-11-18 20:05    [W:0.058 / U:0.548 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site