USB: isp1760: Use resource_size

Use the resource_size function instead of manually calculating the
resource size.  This reduces the chance of introducing off-by-one
errors.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 5 insertions, 6 deletions

diff --git a/drivers/usb/host/isp1760-if.c b/drivers/usb/host/isp1760-if.c
index 42a094605c92..8f0259eaa2c7 100644
--- a/drivers/usb/host/isp1760-if.c
+++ b/drivers/usb/host/isp1760-if.c
@@ -36,7 +36,7 @@ static int of_isp1760_probe(struct of_device *dev,
         struct resource memory;
         struct of_irq oirq;
         int virq;
-        u64 res_len;
+        resource_size_t res_len;
         int ret;
         const unsigned int *prop;
         unsigned int devflags = 0;
@@ -45,13 +45,12 @@ static int of_isp1760_probe(struct of_device *dev,
         if (ret)
                 return -ENXIO;
 
-        res = request_mem_region(memory.start, memory.end - memory.start + 1,
-                        dev_name(&dev->dev));
+        res_len = resource_size(&memory);
+
+        res = request_mem_region(memory.start, res_len, dev_name(&dev->dev));
         if (!res)
                 return -EBUSY;
 
-        res_len = memory.end - memory.start + 1;
-
         if (of_irq_map_one(dp, 0, &oirq)) {
                 ret = -ENODEV;
                 goto release_reg;
@@ -92,7 +91,7 @@ static int of_isp1760_probe(struct of_device *dev,
         return ret;
 
 release_reg:
-        release_mem_region(memory.start, memory.end - memory.start + 1);
+        release_mem_region(memory.start, res_len);
         return ret;
 }