commit 7dedc002c0ec676590bf78ae8d76f2ffd51564f6
author Nenghua Cao <nhcao@marvell.com> Mon Jan 20 20:39:01 2014 +0800
committer Vinod Koul <vinod.koul@intel.com> Thu Mar 06 14:49:54 2014 +0530
tree 728cd0881737a0e7032a7e585803190af4c68253
parent f0b507774449ec35fbfd7173e5fc7dd4df71a81c

dma: mmp_tdma: move to generic device tree binding

    This patch makes the mmp_tdma controller able to provide DMA
resources in DT environments by providing an dma xlate function to
get the generic DMA device tree helper support. Then DMA clients only
need to call dma_request_slave_channel() for requesting a DMA channel
from dmaengine.

Signed-off-by: Nenghua Cao <nhcao@marvell.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/mmp_tdma.c

diff --git a/drivers/dma/mmp_tdma.c b/drivers/dma/mmp_tdma.c
index 33f96aa..724f7f4 100644
--- a/drivers/dma/mmp_tdma.c
+++ b/drivers/dma/mmp_tdma.c
@@ -22,6 +22,7 @@
 #include <mach/regs-icu.h>
 #include <linux/platform_data/dma-mmp_tdma.h>
 #include <linux/of_device.h>
+#include <linux/of_dma.h>
 
 #include "dmaengine.h"
 
@@ -541,6 +542,45 @@
 	return 0;
 }
 
+struct mmp_tdma_filter_param {
+	struct device_node *of_node;
+	unsigned int chan_id;
+};
+
+static bool mmp_tdma_filter_fn(struct dma_chan *chan, void *fn_param)
+{
+	struct mmp_tdma_filter_param *param = fn_param;
+	struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
+	struct dma_device *pdma_device = tdmac->chan.device;
+
+	if (pdma_device->dev->of_node != param->of_node)
+		return false;
+
+	if (chan->chan_id != param->chan_id)
+		return false;
+
+	return true;
+}
+
+struct dma_chan *mmp_tdma_xlate(struct of_phandle_args *dma_spec,
+			       struct of_dma *ofdma)
+{
+	struct mmp_tdma_device *tdev = ofdma->of_dma_data;
+	dma_cap_mask_t mask = tdev->device.cap_mask;
+	struct mmp_tdma_filter_param param;
+
+	if (dma_spec->args_count != 1)
+		return NULL;
+
+	param.of_node = ofdma->of_node;
+	param.chan_id = dma_spec->args[0];
+
+	if (param.chan_id >= TDMA_CHANNEL_NUM)
+		return NULL;
+
+	return dma_request_channel(mask, mmp_tdma_filter_fn, &param);
+}
+
 static struct of_device_id mmp_tdma_dt_ids[] = {
 	{ .compatible = "marvell,adma-1.0", .data = (void *)MMP_AUD_TDMA},
 	{ .compatible = "marvell,pxa910-squ", .data = (void *)PXA910_SQU},
@@ -631,6 +671,16 @@
 		return ret;
 	}
 
+	if (pdev->dev.of_node) {
+		ret = of_dma_controller_register(pdev->dev.of_node,
+							mmp_tdma_xlate, tdev);
+		if (ret) {
+			dev_err(tdev->device.dev,
+				"failed to register controller\n");
+			dma_async_device_unregister(&tdev->device);
+		}
+	}
+
 	dev_info(tdev->device.dev, "initialized\n");
 	return 0;
 }