dma: pl330: split off common code to give back descriptors

This patch adds __pl330_giveback_descs which give back descriptors when fails
allocating descriptors. It requires to eliminate duplication for
pl330_prep_dma_sg which will be added later.

Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Acked-by : Jassi Brar <jassisinghbrar@gmail.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index d8c10449fb420e6415c60d5e8b99d00741cdf72b..facd23afacebea739cadd099dfe5899cca8c17b3 100644 (file)
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -2814,6 +2814,28 @@ pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
        return &desc->txd;
 }
 
+static void __pl330_giveback_desc(struct dma_pl330_dmac *pdmac,
+                                 struct dma_pl330_desc *first)
+{
+       unsigned long flags;
+       struct dma_pl330_desc *desc;
+
+       if (!first)
+               return;
+
+       spin_lock_irqsave(&pdmac->pool_lock, flags);
+
+       while (!list_empty(&first->node)) {
+               desc = list_entry(first->node.next,
+                               struct dma_pl330_desc, node);
+               list_move_tail(&desc->node, &pdmac->desc_pool);
+       }
+
+       list_move_tail(&first->node, &pdmac->desc_pool);
+
+       spin_unlock_irqrestore(&pdmac->pool_lock, flags);
+}
+
 static struct dma_async_tx_descriptor *
 pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                unsigned int sg_len, enum dma_transfer_direction direction,
@@ -2822,7 +2844,6 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
        struct dma_pl330_desc *first, *desc = NULL;
        struct dma_pl330_chan *pch = to_pchan(chan);
        struct scatterlist *sg;
-       unsigned long flags;
        int i;
        dma_addr_t addr;
 
@@ -2842,20 +2863,7 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                        dev_err(pch->dmac->pif.dev,
                                "%s:%d Unable to fetch desc\n",
                                __func__, __LINE__);
-                       if (!first)
-                               return NULL;
-
-                       spin_lock_irqsave(&pdmac->pool_lock, flags);
-
-                       while (!list_empty(&first->node)) {
-                               desc = list_entry(first->node.next,
-                                               struct dma_pl330_desc, node);
-                               list_move_tail(&desc->node, &pdmac->desc_pool);
-                       }
-
-                       list_move_tail(&first->node, &pdmac->desc_pool);
-
-                       spin_unlock_irqrestore(&pdmac->pool_lock, flags);
+                       __pl330_giveback_desc(pdmac, first);
 
                        return NULL;
                }