lib: devres: prepare devm_ioremap_resource() for more variants

We want to add the write-combined variant of devm_ioremap_resource().
Let's first implement __devm_ioremap_resource() which takes
an additional argument type. The types are the same as for
__devm_ioremap(). The existing devm_ioremap_resource() now simply
calls __devm_ioremap_resource() with regular DEVM_IOREMAP type.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20191022084318.22256-3-brgl@bgdev.plSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

lib/devres.c

@@ -114,25 +114,9 @@ void devm_iounmap(struct device *dev, void __iomem *addr)
 }
 EXPORT_SYMBOL(devm_iounmap);
 
-/**
- * devm_ioremap_resource() - check, request region, and ioremap resource
- * @dev: generic device to handle the resource for
- * @res: resource to be handled
- *
- * Checks that a resource is a valid memory region, requests the memory
- * region and ioremaps it. All operations are managed and will be undone
- * on driver detach.
- *
- * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
- * on failure. Usage example:
- *
- *	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- *	base = devm_ioremap_resource(&pdev->dev, res);
- *	if (IS_ERR(base))
- *		return PTR_ERR(base);
- */
-void __iomem *devm_ioremap_resource(struct device *dev,
-				    const struct resource *res)
+static void __iomem *
+__devm_ioremap_resource(struct device *dev, const struct resource *res,
+			enum devm_ioremap_type type)
 {
 	resource_size_t size;
 	void __iomem *dest_ptr;
@@ -151,7 +135,7 @@ void __iomem *devm_ioremap_resource(struct device *dev,
 		return IOMEM_ERR_PTR(-EBUSY);
 	}
 
-	dest_ptr = devm_ioremap(dev, res->start, size);
+	dest_ptr = __devm_ioremap(dev, res->start, size, type);
 	if (!dest_ptr) {
 		dev_err(dev, "ioremap failed for resource %pR\n", res);
 		devm_release_mem_region(dev, res->start, size);
@@ -160,6 +144,29 @@ void __iomem *devm_ioremap_resource(struct device *dev,
 
 	return dest_ptr;
 }
+
+/**
+ * devm_ioremap_resource() - check, request region, and ioremap resource
+ * @dev: generic device to handle the resource for
+ * @res: resource to be handled
+ *
+ * Checks that a resource is a valid memory region, requests the memory
+ * region and ioremaps it. All operations are managed and will be undone
+ * on driver detach.
+ *
+ * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
+ * on failure. Usage example:
+ *
+ *	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ *	base = devm_ioremap_resource(&pdev->dev, res);
+ *	if (IS_ERR(base))
+ *		return PTR_ERR(base);
+ */
+void __iomem *devm_ioremap_resource(struct device *dev,
+				    const struct resource *res)
+{
+	return __devm_ioremap_resource(dev, res, DEVM_IOREMAP);
+}
 EXPORT_SYMBOL(devm_ioremap_resource);
 
 /*