ARM: Orion: EHCI: Add support for enabling clocks

Not all platforms support gating the clock, so it is not an error if
the clock does not exist. However, if it does exist, we should
enable/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>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/usb/host/ehci-orion.c b/drivers/usb/host/ehci-orion.c
index 6c6a5a3b4ea7..82de1073aa52 100644
--- a/drivers/usb/host/ehci-orion.c
+++ b/drivers/usb/host/ehci-orion.c
@@ -12,6 +12,7 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/mbus.h>
+#include <linux/clk.h>
 #include <plat/ehci-orion.h>
 
 #define rdl(off)        __raw_readl(hcd->regs + (off))
@@ -198,6 +199,7 @@ static int __devinit ehci_orion_drv_probe(struct platform_device *pdev)
         struct resource *res;
         struct usb_hcd *hcd;
         struct ehci_hcd *ehci;
+        struct clk *clk;
         void __iomem *regs;
         int irq, err;
 
@@ -238,6 +240,14 @@ static int __devinit ehci_orion_drv_probe(struct platform_device *pdev)
                 goto err2;
         }
 
+        /* 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);
+        }
+
         hcd = usb_create_hcd(&ehci_orion_hc_driver,
                         &pdev->dev, dev_name(&pdev->dev));
         if (!hcd) {
@@ -301,12 +311,18 @@ err1:
 static int __exit ehci_orion_drv_remove(struct platform_device *pdev)
 {
         struct usb_hcd *hcd = platform_get_drvdata(pdev);
+        struct clk *clk;
 
         usb_remove_hcd(hcd);
         iounmap(hcd->regs);
         release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
         usb_put_hcd(hcd);
 
+        clk = clk_get(&pdev->dev, NULL);
+        if (!IS_ERR(clk)) {
+                clk_disable_unprepare(clk);
+                clk_put(clk);
+        }
         return 0;
 }