From c33b644cb31899265ec5102a4ed45c44269dde95 Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 25 May 2012 15:41:13 +0100 Subject: dmaengine: PL08x: start next descriptor from irq context Rather than waiting for the tasklet to run, we can start the next descriptor from interrupt context, as soon as we know that the previous descriptor has completed. Acked-by: Linus Walleij Tested-by: Linus Walleij Signed-off-by: Russell King --- drivers/dma/amba-pl08x.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'drivers/dma') diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c index b6132845e65c..30b6921f094f 100644 --- a/drivers/dma/amba-pl08x.c +++ b/drivers/dma/amba-pl08x.c @@ -1671,10 +1671,7 @@ static void pl08x_tasklet(unsigned long data) spin_lock_irqsave(&plchan->lock, flags); list_splice_tail_init(&plchan->done_list, &head); - /* If a new descriptor is queued, set it up plchan->at is NULL here */ - if (!list_empty(&plchan->issued_list)) { - pl08x_start_next_txd(plchan); - } else if (!list_empty(&plchan->pend_list) || plchan->phychan_hold) { + if (plchan->at || !list_empty(&plchan->pend_list) || plchan->phychan_hold) { /* * This channel is still in use - we have a new txd being * prepared and will soon be queued. Don't give up the @@ -1786,6 +1783,10 @@ static irqreturn_t pl08x_irq(int irq, void *dev) pl08x_release_mux(plchan); dma_cookie_complete(&tx->tx); list_add_tail(&tx->node, &plchan->done_list); + + /* And start the next descriptor */ + if (!list_empty(&plchan->issued_list)) + pl08x_start_next_txd(plchan); } spin_unlock(&plchan->lock); -- cgit v1.2.3