[PATCH] dmaengine:sirf:take clock and enable it while probing

[Barry Song]

From: Barry Song <Baohua.Song at csr.com>

there is hardcode which enabled the clock of dmaengine before,
this patch takes the clock by standard clock API and enable it
in probe.

Signed-off-by: Barry Song <Baohua.Song at csr.com>
---
 drivers/dma/sirf-dma.c |   11 +++++++++++
 1 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/drivers/dma/sirf-dma.c b/drivers/dma/sirf-dma.c
index 1d627e2..c439529 100644
--- a/drivers/dma/sirf-dma.c
+++ b/drivers/dma/sirf-dma.c
@@ -16,6 +16,7 @@
 #include <linux/of_address.h>
 #include <linux/of_device.h>
 #include <linux/of_platform.h>
+#include <linux/clk.h>
 #include <linux/sirfsoc_dma.h>
 
 #include "dmaengine.h"
@@ -78,6 +79,7 @@ struct sirfsoc_dma {
 	struct sirfsoc_dma_chan		channels[SIRFSOC_DMA_CHANNELS];
 	void __iomem			*base;
 	int				irq;
+	struct clk			*clk;
 	bool				is_marco;
 };
 
@@ -639,6 +641,12 @@ static int sirfsoc_dma_probe(struct platform_device *op)
 		return -EINVAL;
 	}
 
+	sdma->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(sdma->clk)) {
+		dev_err(dev, "failed to get a clock.\n");
+		return PTR_ERR(sdma->clk);
+	}
+
 	ret = of_address_to_resource(dn, 0, &res);
 	if (ret) {
 		dev_err(dev, "Error parsing memory region!\n");
@@ -698,6 +706,8 @@ static int sirfsoc_dma_probe(struct platform_device *op)
 
 	tasklet_init(&sdma->tasklet, sirfsoc_dma_tasklet, (unsigned long)sdma);
 
+	clk_prepare_enable(sdma->clk);
+
 	/* Register DMA engine */
 	dev_set_drvdata(dev, sdma);
 	ret = dma_async_device_register(dma);
@@ -720,6 +730,7 @@ static int sirfsoc_dma_remove(struct platform_device *op)
 	struct device *dev = &op->dev;
 	struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
 
+	clk_disable_unprepare(sdma->clk);
 	dma_async_device_unregister(&sdma->dma);
 	free_irq(sdma->irq, sdma);
 	irq_dispose_mapping(sdma->irq);
-- 
1.7.5.4



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