1 files changed, 21 insertions, 5 deletions

diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index 3d763fdf99b7..768d973d0ded 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -204,6 +204,7 @@ static void amba_device_release(struct device *dev)
 int amba_device_register(struct amba_device *dev, struct resource *parent)
 {
         u32 pid, cid;
+        u32 size;
         void __iomem *tmp;
         int i, ret;
 
@@ -219,16 +220,25 @@ int amba_device_register(struct amba_device *dev, struct resource *parent)
         if (ret)
                 goto err_out;
 
-        tmp = ioremap(dev->res.start, SZ_4K);
+        /*
+         * Dynamically calculate the size of the resource
+         * and use this for iomap
+         */
+        size = resource_size(&dev->res);
+        tmp = ioremap(dev->res.start, size);
         if (!tmp) {
                 ret = -ENOMEM;
                 goto err_release;
         }
 
+        /*
+         * Read pid and cid based on size of resource
+         * they are located at end of region
+         */
         for (pid = 0, i = 0; i < 4; i++)
-                pid |= (readl(tmp + 0xfe0 + 4 * i) & 255) << (i * 8);
+                pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) << (i * 8);
         for (cid = 0, i = 0; i < 4; i++)
-                cid |= (readl(tmp + 0xff0 + 4 * i) & 255) << (i * 8);
+                cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) << (i * 8);
 
         iounmap(tmp);
 
@@ -343,11 +353,14 @@ amba_find_device(const char *busid, struct device *parent, unsigned int id,
 int amba_request_regions(struct amba_device *dev, const char *name)
 {
         int ret = 0;
+        u32 size;
 
         if (!name)
                 name = dev->dev.driver->name;
 
-        if (!request_mem_region(dev->res.start, SZ_4K, name))
+        size = resource_size(&dev->res);
+
+        if (!request_mem_region(dev->res.start, size, name))
                 ret = -EBUSY;
 
         return ret;
@@ -361,7 +374,10 @@ int amba_request_regions(struct amba_device *dev, const char *name)
  */
 void amba_release_regions(struct amba_device *dev)
 {
-        release_mem_region(dev->res.start, SZ_4K);
+        u32 size;
+
+        size = resource_size(&dev->res);
+        release_mem_region(dev->res.start, size);
 }
 
 EXPORT_SYMBOL(amba_driver_register);