[PATCH V7 01/13] of: platform: Add of_find_any_device_by_node()

From: Viresh Kumar
Date: Fri Feb 23 2018 - 05:27:40 EST


This creates a new helper that returns the struct device corresponding
to a struct device_node. This currently works only for amba and platform
devices, but can be easily extended to include other bus types.

This also creates an internal of_find_amba_device_by_node() helper,
which isn't exported as of now.

Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
drivers/of/platform.c | 55 +++++++++++++++++++++++++++++++++++++++++++++
include/linux/of_platform.h | 5 +++++
2 files changed, 60 insertions(+)

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index c00d81dfac0b..72853f9043e6 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -55,6 +55,61 @@ struct platform_device *of_find_device_by_node(struct device_node *np)
}
EXPORT_SYMBOL(of_find_device_by_node);

+#ifdef CONFIG_ARM_AMBA
+/**
+ * of_find_amba_device_by_node - Find the amba_device associated with a node
+ * @np: Pointer to device tree node
+ *
+ * Takes a reference to the embedded struct device which needs to be dropped
+ * after use.
+ *
+ * Returns amba_device pointer, or NULL if not found
+ */
+static struct amba_device *of_find_amba_device_by_node(struct device_node *np)
+{
+ struct device *dev;
+
+ dev = bus_find_device(&amba_bustype, NULL, np, of_dev_node_match);
+ return dev ? to_amba_device(dev) : NULL;
+}
+#else
+static inline struct amba_device *of_find_amba_device_by_node(struct device_node *np)
+{
+ return NULL;
+}
+#endif
+
+/**
+ * of_find_any_device_by_node - Find the struct device associated with a node
+ * @np: Pointer to device tree node
+ *
+ * Takes a reference to the embedded struct device which needs to be dropped
+ * after use.
+ *
+ * This currently supports only AMBA and platform devices.
+ *
+ * Returns struct device pointer, or NULL if not found
+ */
+struct device *of_find_any_device_by_node(struct device_node *np)
+{
+ struct device *dev = NULL;
+
+ if (of_device_is_compatible(np, "arm,primecell")) {
+ struct amba_device *adev = of_find_amba_device_by_node(np);
+
+ if (adev)
+ dev = &adev->dev;
+ } else {
+ struct platform_device *pdev = of_find_device_by_node(np);
+
+ if (pdev)
+ dev = &pdev->dev;
+ }
+
+ return dev;
+}
+EXPORT_SYMBOL(of_find_any_device_by_node);
+
#ifdef CONFIG_OF_ADDRESS
/*
* The following routines scan a subtree and registers a device for
diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h
index 84a966623e78..5fb20afaf895 100644
--- a/include/linux/of_platform.h
+++ b/include/linux/of_platform.h
@@ -54,11 +54,16 @@ extern struct platform_device *of_device_alloc(struct device_node *np,
struct device *parent);
#ifdef CONFIG_OF
extern struct platform_device *of_find_device_by_node(struct device_node *np);
+extern struct device *of_find_any_device_by_node(struct device_node *np);
#else
static inline struct platform_device *of_find_device_by_node(struct device_node *np)
{
return NULL;
}
+static inline struct device *of_find_any_device_by_node(struct device_node *np)
+{
+ return NULL;
+}
#endif

/* Platform devices and busses creation */
--
2.15.0.194.g9af6a3dea062