diff options
Diffstat (limited to 'arch/arm/plat-mxs/dmaengine.c')
| -rw-r--r-- | arch/arm/plat-mxs/dmaengine.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/arch/arm/plat-mxs/dmaengine.c b/arch/arm/plat-mxs/dmaengine.c index 453346e4057f..0c2485b18506 100644 --- a/arch/arm/plat-mxs/dmaengine.c +++ b/arch/arm/plat-mxs/dmaengine.c @@ -127,14 +127,16 @@ int mxs_dma_enable(int channel) if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) return -EINVAL; + /* + * neednot mutex lock, this function will be called in irq context. + * The mutex may cause process schedule. + */ pdma = pchan->dma; - mutex_lock(&mxs_dma_mutex); spin_lock_irqsave(&pchan->lock, flags); if (pchan->pending_num && pdma->enable) ret = pdma->enable(pchan, channel - pdma->chan_base); pchan->flags |= MXS_DMA_FLAGS_BUSY; spin_unlock_irqrestore(&pchan->lock, flags); - mutex_unlock(&mxs_dma_mutex); return ret; } EXPORT_SYMBOL(mxs_dma_enable); @@ -151,17 +153,19 @@ void mxs_dma_disable(int channel) return; if (!(pchan->flags & MXS_DMA_FLAGS_BUSY)) return; + /* + * neednot mutex lock, this function will be called in irq context. + * The mutex may cause process schedule. + */ pdma = pchan->dma; - mutex_lock(&mxs_dma_mutex); spin_lock_irqsave(&pchan->lock, flags); if (pdma->disable) pdma->disable(pchan, channel - pdma->chan_base); pchan->flags &= ~MXS_DMA_FLAGS_BUSY; pchan->active_num = 0; pchan->pending_num = 0; - list_splice(&pchan->active, &pchan->done); + list_splice_init(&pchan->active, &pchan->done); spin_unlock_irqrestore(&pchan->lock, flags); - mutex_unlock(&mxs_dma_mutex); } EXPORT_SYMBOL(mxs_dma_disable); |