[PATCH 2/3] dmaengine: sprd: Add new DMA engine translation function

[Baolin Wang <baolin.wang@xxxxxxxxxx>]

Add new DMA engine translation function to get the hardware slave id
of the corresponding DMA engine channel. Meanwhile we do not need
to set default slave id in sprd_dma_alloc_chan_resources(), remove it.

Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
---
 drivers/dma/sprd-dma.c |   49 ++++++++++++++++++++++++++++--------------------
 1 file changed, 29 insertions(+), 20 deletions(-)

diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
index e2f0167..7d180bb 100644
--- a/drivers/dma/sprd-dma.c
+++ b/drivers/dma/sprd-dma.c
@@ -204,9 +204,9 @@ struct sprd_dma_dev {
 	struct sprd_dma_chn	channels[0];
 };
 
-static bool sprd_dma_filter_fn(struct dma_chan *chan, void *param);
-static struct of_dma_filter_info sprd_dma_info = {
-	.filter_fn = sprd_dma_filter_fn,
+struct sprd_dma_filter_param {
+	u32 chn_id;
+	u32 slave_id;
 };
 
 static inline struct sprd_dma_chn *to_sprd_dma_chan(struct dma_chan *c)
@@ -580,15 +580,7 @@ static irqreturn_t dma_irq_handle(int irq, void *dev_id)
 
 static int sprd_dma_alloc_chan_resources(struct dma_chan *chan)
 {
-	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
-	int ret;
-
-	ret = pm_runtime_get_sync(chan->device->dev);
-	if (ret < 0)
-		return ret;
-
-	schan->dev_id = SPRD_DMA_SOFTWARE_UID;
-	return 0;
+	return pm_runtime_get_sync(chan->device->dev);
 }
 
 static void sprd_dma_free_chan_resources(struct dma_chan *chan)
@@ -1022,12 +1014,31 @@ static bool sprd_dma_filter_fn(struct dma_chan *chan, void *param)
 {
 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
 	struct sprd_dma_dev *sdev = to_sprd_dma_dev(&schan->vc.chan);
-	u32 req = *(u32 *)param;
+	struct sprd_dma_filter_param *sparam = param;
 
-	if (req < sdev->total_chns)
-		return req == schan->chn_num + 1;
-	else
-		return false;
+	if (sparam->chn_id < sdev->total_chns &&
+	    sparam->chn_id == schan->chn_num + 1) {
+		schan->dev_id = sparam->slave_id;
+		return true;
+	}
+
+	return false;
+}
+
+static struct dma_chan *sprd_dma_xlate(struct of_phandle_args *dma_spec,
+				       struct of_dma *ofdma)
+{
+	struct sprd_dma_dev *sdev = ofdma->of_dma_data;
+	dma_cap_mask_t mask = sdev->dma_dev.cap_mask;
+	struct sprd_dma_filter_param param;
+
+	if (dma_spec->args_count != 2)
+		return NULL;
+
+	param.chn_id = dma_spec->args[0];
+	param.slave_id = dma_spec->args[1];
+
+	return dma_request_channel(mask, sprd_dma_filter_fn, &param);
 }
 
 static int sprd_dma_probe(struct platform_device *pdev)
@@ -1133,9 +1144,7 @@ static int sprd_dma_probe(struct platform_device *pdev)
 		goto err_register;
 	}
 
-	sprd_dma_info.dma_cap = sdev->dma_dev.cap_mask;
-	ret = of_dma_controller_register(np, of_dma_simple_xlate,
-					 &sprd_dma_info);
+	ret = of_dma_controller_register(np, sprd_dma_xlate, sdev);
 	if (ret)
 		goto err_of_register;
 
-- 
1.7.9.5