diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-05-25 13:51:19 +0400 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-07-01 17:15:51 +0400 |
| commit | a936e793136b4238ef287cfbbdd25ebb78214529 (patch) | |
| tree | ca2d59b06aa7f3cb9c5830b77eaf00375c980f1b /drivers/dma | |
| parent | 5e2479bd0e0dc41f2b9f6b4345bc5d4557837056 (diff) | |
| download | linux-a936e793136b4238ef287cfbbdd25ebb78214529.tar.xz | |
dmaengine: PL08x: convert to a list of completed descriptors
Convert PL08x to use a list of completed descriptors rather than
merely relying upon a single pointer. This makes it possible to
schedule the tasklet for other purposes, and makes our behaviour
similar to virt-dma.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/amba-pl08x.c | 30 |
1 files changed, 20 insertions, 10 deletions
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c index ac9fdccb2c19..54e3eb0b3723 100644 --- a/drivers/dma/amba-pl08x.c +++ b/drivers/dma/amba-pl08x.c @@ -219,6 +219,7 @@ enum pl08x_dma_chan_state { * @cd: channel platform data * @runtime_addr: address for RX/TX according to the runtime config * @pend_list: queued transactions pending on this channel + * @done_list: list of completed transactions * @at: active transaction on this channel * @lock: a lock for this channel data * @host: a pointer to the host (internal use) @@ -238,6 +239,7 @@ struct pl08x_dma_chan { const struct pl08x_channel_data *cd; struct dma_slave_config cfg; struct list_head pend_list; + struct list_head done_list; struct pl08x_txd *at; spinlock_t lock; struct pl08x_driver_data *host; @@ -1673,18 +1675,11 @@ static void pl08x_tasklet(unsigned long data) { struct pl08x_dma_chan *plchan = (struct pl08x_dma_chan *) data; struct pl08x_driver_data *pl08x = plchan->host; - struct pl08x_txd *txd; unsigned long flags; + LIST_HEAD(head); spin_lock_irqsave(&plchan->lock, flags); - - txd = plchan->at; - plchan->at = NULL; - - if (txd) { - /* Update last completed */ - dma_cookie_complete(&txd->tx); - } + 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->pend_list)) { @@ -1739,10 +1734,14 @@ static void pl08x_tasklet(unsigned long data) spin_unlock_irqrestore(&plchan->lock, flags); - if (txd) { + while (!list_empty(&head)) { + struct pl08x_txd *txd = list_first_entry(&head, + struct pl08x_txd, node); dma_async_tx_callback callback = txd->tx.callback; void *callback_param = txd->tx.callback_param; + list_del(&txd->node); + /* Don't try to unmap buffers on slave channels */ if (!plchan->slave) pl08x_unmap_buffers(txd); @@ -1782,6 +1781,7 @@ static irqreturn_t pl08x_irq(int irq, void *dev) /* Locate physical channel */ struct pl08x_phy_chan *phychan = &pl08x->phy_chans[i]; struct pl08x_dma_chan *plchan = phychan->serving; + struct pl08x_txd *tx; if (!plchan) { dev_err(&pl08x->adev->dev, @@ -1790,6 +1790,15 @@ static irqreturn_t pl08x_irq(int irq, void *dev) continue; } + spin_lock(&plchan->lock); + tx = plchan->at; + if (tx) { + plchan->at = NULL; + dma_cookie_complete(&tx->tx); + list_add_tail(&tx->node, &plchan->done_list); + } + spin_unlock(&plchan->lock); + /* Schedule tasklet on this channel */ tasklet_schedule(&plchan->tasklet); mask |= (1 << i); @@ -1856,6 +1865,7 @@ static int pl08x_dma_init_virtual_channels(struct pl08x_driver_data *pl08x, spin_lock_init(&chan->lock); INIT_LIST_HEAD(&chan->pend_list); + INIT_LIST_HEAD(&chan->done_list); tasklet_init(&chan->tasklet, pl08x_tasklet, (unsigned long) chan); |