ARM: Orion: XOR: Add support for clk

Some orion platforms can gate the XOR driver clock. If the clock
exisits, unable/disable it as appropriate.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Jamie Lentin <jm@lentin.co.uk>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

2 files changed, 16 insertions, 0 deletions

diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index fa5d55fea46c..0b12e68bf79c 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -25,6 +25,7 @@
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/memory.h>
+#include <linux/clk.h>
 #include <plat/mv_xor.h>
 
 #include "dmaengine.h"
@@ -1307,11 +1308,25 @@ static int mv_xor_shared_probe(struct platform_device *pdev)
         if (dram)
                 mv_xor_conf_mbus_windows(msp, dram);
 
+        /* Not all platforms can gate the clock, so it is not
+         * an error if the clock does not exists.
+         */
+        msp->clk = clk_get(&pdev->dev, NULL);
+        if (!IS_ERR(msp->clk))
+                clk_prepare_enable(msp->clk);
+
         return 0;
 }
 
 static int mv_xor_shared_remove(struct platform_device *pdev)
 {
+        struct mv_xor_shared_private *msp = platform_get_drvdata(pdev);
+
+        if (!IS_ERR(msp->clk)) {
+                clk_disable_unprepare(msp->clk);
+                clk_put(msp->clk);
+        }
+
         return 0;
 }
 
diff --git a/drivers/dma/mv_xor.h b/drivers/dma/mv_xor.h
index 654876b7ba1d..a5b422f5a8ab 100644
--- a/drivers/dma/mv_xor.h
+++ b/drivers/dma/mv_xor.h
@@ -55,6 +55,7 @@
 struct mv_xor_shared_private {
         void __iomem    *xor_base;
         void __iomem    *xor_high_base;
+        struct clk      *clk;
 };