[PATCH 2/2] driver core: platform: Add the helper function devm_platform_get_and_ioremap_resource_byname()

From: Cai Huoqing
Date: Thu Sep 02 2021 - 01:25:10 EST


Since provide the helper function devm_platform_ioremap_resource_byname()
which is wrap platform_get_resource_byname() and devm_ioremap_resource().
But sometimes, many drivers still need to use the resource variables
obtained by platform_get_resource(). In these cases, provide this helper
function devm_platform_get_and_ioremap_resource_byname().

Signed-off-by: Cai Huoqing <caihuoqing@xxxxxxxxx>
---
drivers/base/platform.c | 30 ++++++++++++++++++++++++++----
include/linux/platform_device.h | 3 +++
2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 52a1b94428c8..29e3ad6dde70 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -124,6 +124,31 @@ void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
}
EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);

+/**
+ * devm_platform_get_and_ioremap_resource_byname - call devm_ioremap_resource() for a
+ * platform device and get resource
+ *
+ * @pdev: platform device to use both for memory resource lookup as well as
+ * resource management
+ * @name: name of the resource
+ * @res: optional output parameter to store a pointer to the obtained resource.
+ *
+ * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
+ * on failure.
+ */
+void __iomem *
+devm_platform_get_and_ioremap_resource_byname(struct platform_device *pdev,
+ const char *name, struct resource **res)
+{
+ struct resource *r;
+
+ r = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
+ if (res)
+ *res = r;
+ return devm_ioremap_resource(&pdev->dev, r);
+}
+EXPORT_SYMBOL_GPL(devm_platform_get_and_ioremap_resource_byname);
+
/**
* devm_platform_ioremap_resource_byname - call devm_ioremap_resource for
* a platform device, retrieve the
@@ -140,10 +165,7 @@ void __iomem *
devm_platform_ioremap_resource_byname(struct platform_device *pdev,
const char *name)
{
- struct resource *res;
-
- res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
- return devm_ioremap_resource(&pdev->dev, res);
+ return devm_platform_get_and_ioremap_resource_byname(pdev, name, NULL);
}
EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname);
#endif /* CONFIG_HAS_IOMEM */
diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
index 07e1bba45243..a20f3ecc1cd8 100644
--- a/include/linux/platform_device.h
+++ b/include/linux/platform_device.h
@@ -66,6 +66,9 @@ extern void __iomem *
devm_platform_ioremap_resource(struct platform_device *pdev,
unsigned int index);
extern void __iomem *
+devm_platform_get_and_ioremap_resource_byname(struct platform_device *pdev,
+ const char *name, struct resource **res);
+extern void __iomem *
devm_platform_ioremap_resource_byname(struct platform_device *pdev,
const char *name);
extern int platform_get_irq(struct platform_device *, unsigned int);
--
2.25.1