ARM: Orion: NAND: Add support for clk, if there is one.

Not all orion platforms can gate the clock, but if it does exist,
enable/disable it as appropriate.

v2: Fix the name of the clkdev entry.

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

arch/arm/mach-kirkwood/common.c

@@ -116,6 +116,7 @@ void __init kirkwood_clk_init(void)
 	orion_clkdev_add("0", "sata_mv.0", sata0);
 	orion_clkdev_add("1", "sata_mv.0", sata1);
 	orion_clkdev_add(NULL, "orion-ehci.0", usb0);
+	orion_clkdev_add(NULL, "orion_nand", runit);
 }
 
 /*****************************************************************************

drivers/mtd/nand/orion_nand.c

@@ -16,6 +16,8 @@
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/nand.h>
 #include <linux/mtd/partitions.h>
+#include <linux/clk.h>
+#include <linux/err.h>
 #include <asm/io.h>
 #include <asm/sizes.h>
 #include <mach/hardware.h>
@@ -77,6 +79,7 @@ static int __init orion_nand_probe(struct platform_device *pdev)
 	struct nand_chip *nc;
 	struct orion_nand_data *board;
 	struct resource *res;
+	struct clk *clk;
 	void __iomem *io_base;
 	int ret = 0;
 
@@ -123,6 +126,14 @@ static int __init orion_nand_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, mtd);
 
+	/* Not all platforms can gate the clock, so it is not
+	   an error if the clock does not exists. */
+	clk = clk_get(&pdev->dev, NULL);
+	if (!IS_ERR(clk)) {
+		clk_prepare_enable(clk);
+		clk_put(clk);
+	}
+
 	if (nand_scan(mtd, 1)) {
 		ret = -ENXIO;
 		goto no_dev;
@@ -151,13 +162,20 @@ static int __devexit orion_nand_remove(struct platform_device *pdev)
 {
 	struct mtd_info *mtd = platform_get_drvdata(pdev);
 	struct nand_chip *nc = mtd->priv;
+	struct clk *clk;
 
 	nand_release(mtd);
 
 	iounmap(nc->IO_ADDR_W);
 
 	kfree(nc);
 
+	clk = clk_get(&pdev->dev, NULL);
+	if (!IS_ERR(clk)) {
+		clk_disable_unprepare(clk);
+		clk_put(clk);
+	}
+
 	return 0;
 }