firewire: ohci: optimize iso context checks in the interrupt handler

When the isochRx/isochTx bit is clear, we do not need to read the
corresponding iso interrupt event register.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This commit is contained in:
Clemens Ladisch 2010-11-30 08:25:05 +01:00 committed by Stefan Richter
parent 5b06db166c
commit 2dd5bed593

View file

@ -1813,22 +1813,28 @@ static irqreturn_t irq_handler(int irq, void *data)
if (event & OHCI1394_respTxComplete)
tasklet_schedule(&ohci->at_response_ctx.tasklet);
iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
if (event & OHCI1394_isochRx) {
iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
while (iso_event) {
i = ffs(iso_event) - 1;
tasklet_schedule(&ohci->ir_context_list[i].context.tasklet);
iso_event &= ~(1 << i);
while (iso_event) {
i = ffs(iso_event) - 1;
tasklet_schedule(
&ohci->ir_context_list[i].context.tasklet);
iso_event &= ~(1 << i);
}
}
iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
if (event & OHCI1394_isochTx) {
iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
while (iso_event) {
i = ffs(iso_event) - 1;
tasklet_schedule(&ohci->it_context_list[i].context.tasklet);
iso_event &= ~(1 << i);
while (iso_event) {
i = ffs(iso_event) - 1;
tasklet_schedule(
&ohci->it_context_list[i].context.tasklet);
iso_event &= ~(1 << i);
}
}
if (unlikely(event & OHCI1394_regAccessFail))