[RFC 06/13] device core: Introduce dev_64bit_mmio_supported()

[Nicolas Saenz Julienne]

This helper function will be help drivers ascertain whether they can use
64-bit memory accesses.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne at suse.de>
---
 include/linux/device.h | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/include/linux/device.h b/include/linux/device.h
index bd94aa0cbd72..e9b4b2f99a44 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -826,6 +826,23 @@ static inline int dev_num_vf(struct device *dev)
 	return 0;
 }
 
+#if defined(CONFIG_ARCH_HAS_64BIT_MMIO_BROKEN)
+static inline bool dev_64bit_mmio_supported(struct device *dev)
+{
+	return !dev->mmio_64bit_broken;
+}
+#elif defined(CONFIG_64BIT)
+static inline bool dev_64bit_mmio_supported(struct device *dev)
+{
+	return true;
+}
+#else
+static inline bool dev_64bit_mmio_supported(struct device *dev)
+{
+	return false;
+}
+#endif
+
 /*
  * Root device objects for grouping under /sys/devices
  */
-- 
2.30.1