lib: devres: add a helper function for ioremap_uc

Implement a resource managed strongly uncachable ioremap function.

Cc: <stable@vger.kernel.org> # v4.19+
Tested-by: AceLan Kao <acelan.kao@canonical.com>
Signed-off-by: Tuowen Zhao <ztuowen@gmail.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/lib/devres.c b/lib/devres.c
index 6a0e9bd..17624d3 100644
--- a/lib/devres.c
+++ b/lib/devres.c
@@ -9,6 +9,7 @@
 enum devm_ioremap_type {
 	DEVM_IOREMAP = 0,
 	DEVM_IOREMAP_NC,
+	DEVM_IOREMAP_UC,
 	DEVM_IOREMAP_WC,
 };
 
@@ -39,6 +40,9 @@ static void __iomem *__devm_ioremap(struct device *dev, resource_size_t offset,
 	case DEVM_IOREMAP_NC:
 		addr = ioremap_nocache(offset, size);
 		break;
+	case DEVM_IOREMAP_UC:
+		addr = ioremap_uc(offset, size);
+		break;
 	case DEVM_IOREMAP_WC:
 		addr = ioremap_wc(offset, size);
 		break;
@@ -69,6 +73,21 @@ void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
 EXPORT_SYMBOL(devm_ioremap);
 
 /**
+ * devm_ioremap_uc - Managed ioremap_uc()
+ * @dev: Generic device to remap IO address for
+ * @offset: Resource address to map
+ * @size: Size of map
+ *
+ * Managed ioremap_uc().  Map is automatically unmapped on driver detach.
+ */
+void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
+			      resource_size_t size)
+{
+	return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_UC);
+}
+EXPORT_SYMBOL_GPL(devm_ioremap_uc);
+
+/**
  * devm_ioremap_nocache - Managed ioremap_nocache()
  * @dev: Generic device to remap IO address for
  * @offset: Resource address to map