[PATCH v2 1/5] driver core: platform: Introduce platform_get_mem_or_io()

From: Andy Shevchenko
Date: Wed Dec 09 2020 - 15:38:59 EST


There are at least few existing users of the proposed API which
retrieves either MEM or IO resource from platform device.

Make it common to utilize in the existing and new users.

Cc: Eric Auger <eric.auger@xxxxxxxxxx>
Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
Cc: kvm@xxxxxxxxxxxxxxx
Cc: linux-usb@xxxxxxxxxxxxxxx
Cc: Peng Hao <peng.hao2@xxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>
---
v2: moved to C-file and renamed for the sake of consistency with the rest
platform code

drivers/base/platform.c | 15 +++++++++++++++
include/linux/platform_device.h | 3 +++
2 files changed, 18 insertions(+)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 88aef93eb4dd..af0c37f720e6 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -63,6 +63,21 @@ struct resource *platform_get_resource(struct platform_device *dev,
}
EXPORT_SYMBOL_GPL(platform_get_resource);

+struct resource *platform_get_mem_or_io(struct platform_device *dev,
+ unsigned int num)
+{
+ u32 i;
+
+ for (i = 0; i < dev->num_resources; i++) {
+ struct resource *r = &dev->resource[i];
+
+ if ((resource_type(r) & (IORESOURCE_MEM|IORESOURCE_IO)) && num-- == 0)
+ return r;
+ }
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(platform_get_mem_or_io);
+
#ifdef CONFIG_HAS_IOMEM
/**
* devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a
diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
index 77a2aada106d..ee6a9f10c2c7 100644
--- a/include/linux/platform_device.h
+++ b/include/linux/platform_device.h
@@ -52,6 +52,9 @@ extern struct device platform_bus;

extern struct resource *platform_get_resource(struct platform_device *,
unsigned int, unsigned int);
+extern struct resource *platform_get_mem_or_io(struct platform_device *,
+ unsigned int);
+
extern struct device *
platform_find_device_by_driver(struct device *start,
const struct device_driver *drv);
--
2.29.2