dmaengine: Add support for MEMCPY for imx-dma.
Javier Martin [Tue, 28 Feb 2012 16:08:17 +0000 (17:08 +0100)]
MEMCPY transfers allow DMA copies from memory to
memory. This patch has been tested with dmatest
device driver.

Signed-off-by: Javier Martin <javier.martin@vista-silicon.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>

drivers/dma/imx-dma.c

index b51391a..9a17978 100644 (file)
@@ -195,7 +195,8 @@ static int imxdma_alloc_chan_resources(struct dma_chan *chan)
        struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
        struct imx_dma_data *data = chan->private;
 
-       imxdmac->dma_request = data->dma_request;
+       if (data != NULL)
+               imxdmac->dma_request = data->dma_request;
 
        dma_async_tx_descriptor_init(&imxdmac->desc, chan);
        imxdmac->desc.tx_submit = imxdma_tx_submit;
@@ -327,6 +328,36 @@ static struct dma_async_tx_descriptor *imxdma_prep_dma_cyclic(
        return &imxdmac->desc;
 }
 
+static struct dma_async_tx_descriptor *imxdma_prep_dma_memcpy(
+       struct dma_chan *chan, dma_addr_t dest,
+       dma_addr_t src, size_t len, unsigned long flags)
+{
+       struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
+       struct imxdma_engine *imxdma = imxdmac->imxdma;
+       int ret;
+
+       dev_dbg(imxdma->dev, "%s channel: %d src=0x%x dst=0x%x len=%d\n",
+                       __func__, imxdmac->channel, src, dest, len);
+
+       if (imxdmac->status == DMA_IN_PROGRESS)
+               return NULL;
+       imxdmac->status = DMA_IN_PROGRESS;
+
+       ret = imx_dma_config_channel(imxdmac->imxdma_channel,
+                              IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR,
+                              IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR,
+                              0, 0);
+       if (ret)
+               return NULL;
+
+       ret = imx_dma_setup_single(imxdmac->imxdma_channel, src, len,
+                                  dest, DMA_MODE_WRITE);
+       if (ret)
+               return NULL;
+
+       return &imxdmac->desc;
+}
+
 static void imxdma_issue_pending(struct dma_chan *chan)
 {
        struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
@@ -348,6 +379,7 @@ static int __init imxdma_probe(struct platform_device *pdev)
 
        dma_cap_set(DMA_SLAVE, imxdma->dma_device.cap_mask);
        dma_cap_set(DMA_CYCLIC, imxdma->dma_device.cap_mask);
+       dma_cap_set(DMA_MEMCPY, imxdma->dma_device.cap_mask);
 
        /* Initialize channel parameters */
        for (i = 0; i < MAX_DMA_CHANNELS; i++) {
@@ -381,11 +413,13 @@ static int __init imxdma_probe(struct platform_device *pdev)
        imxdma->dma_device.device_tx_status = imxdma_tx_status;
        imxdma->dma_device.device_prep_slave_sg = imxdma_prep_slave_sg;
        imxdma->dma_device.device_prep_dma_cyclic = imxdma_prep_dma_cyclic;
+       imxdma->dma_device.device_prep_dma_memcpy = imxdma_prep_dma_memcpy;
        imxdma->dma_device.device_control = imxdma_control;
        imxdma->dma_device.device_issue_pending = imxdma_issue_pending;
 
        platform_set_drvdata(pdev, imxdma);
 
+       imxdma->dma_device.copy_align = 2; /* 2^2 = 4 bytes alignment */
        imxdma->dma_device.dev->dma_parms = &imxdma->dma_parms;
        dma_set_max_seg_size(imxdma->dma_device.dev, 0xffffff);