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dmaengine: xilinx_vdma: Simplify spin lock handling 

This patch simplifies the spin lock handling in the driver
by moving locking out of xilinx_dma_start_transfer() API
and xilinx_dma_update_completed_cookie() API.

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Kedareswara rao Appana 2016-02-26 19:33:52 +05:30 committed by Vinod Koul
parent e2b538a77d
commit 26c5e36931
1 changed files with 12 additions and 17 deletions
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29
drivers/dma/xilinx/xilinx_vdma.c
View File

@ -605,17 +605,15 @@ static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan)
{
struct xilinx_vdma_config *config = &chan->config;
struct xilinx_vdma_tx_descriptor *desc, *tail_desc;
unsigned long flags;
u32 reg;
struct xilinx_vdma_tx_segment *tail_segment;
/* This function was invoked with lock held */
if (chan->err)
return;
spin_lock_irqsave(&chan->lock, flags);
if (list_empty(&chan->pending_list))
goto out_unlock;
return;
desc = list_first_entry(&chan->pending_list,
struct xilinx_vdma_tx_descriptor, node);
@ -629,7 +627,7 @@ static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan)
if (chan->has_sg && xilinx_vdma_is_running(chan) &&
!xilinx_vdma_is_idle(chan)) {
dev_dbg(chan->dev, "DMA controller still busy\n");
goto out_unlock;
return;
}
/*
@ -680,7 +678,7 @@ static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan)
xilinx_vdma_start(chan);
if (chan->err)
goto out_unlock;
return;
/* Start the transfer */
if (chan->has_sg) {
@ -700,7 +698,7 @@ static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan)
}
if (!last)
goto out_unlock;
return;
/* HW expects these parameters to be same for one transaction */
vdma_desc_write(chan, XILINX_VDMA_REG_HSIZE, last->hw.hsize);
@ -711,9 +709,6 @@ static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan)
list_splice_tail_init(&chan->pending_list, &chan->active_list);
chan->desc_pendingcount = 0;
out_unlock:
spin_unlock_irqrestore(&chan->lock, flags);
}
/**
@ -723,8 +718,11 @@ out_unlock:
static void xilinx_vdma_issue_pending(struct dma_chan *dchan)
{
struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan);
unsigned long flags;
spin_lock_irqsave(&chan->lock, flags);
xilinx_vdma_start_transfer(chan);
spin_unlock_irqrestore(&chan->lock, flags);
}
/**
@ -736,21 +734,16 @@ static void xilinx_vdma_issue_pending(struct dma_chan *dchan)
static void xilinx_vdma_complete_descriptor(struct xilinx_vdma_chan *chan)
{
struct xilinx_vdma_tx_descriptor *desc, *next;
unsigned long flags;
spin_lock_irqsave(&chan->lock, flags);
/* This function was invoked with lock held */
if (list_empty(&chan->active_list))
goto out_unlock;
return;
list_for_each_entry_safe(desc, next, &chan->active_list, node) {
list_del(&desc->node);
dma_cookie_complete(&desc->async_tx);
list_add_tail(&desc->node, &chan->done_list);
}
out_unlock:
spin_unlock_irqrestore(&chan->lock, flags);
}
/**
@ -861,8 +854,10 @@ static irqreturn_t xilinx_vdma_irq_handler(int irq, void *data)
}
if (status & XILINX_VDMA_DMASR_FRM_CNT_IRQ) {
spin_lock(&chan->lock);
xilinx_vdma_complete_descriptor(chan);
xilinx_vdma_start_transfer(chan);
spin_unlock(&chan->lock);
}
tasklet_schedule(&chan->tasklet);