Driver core: Unified interface for firmware node properties
Add new generic routines are provided for retrieving properties from
device description objects in the platform firmware in case there are
no struct device objects for them (either those objects have not been
created yet or they do not exist at all).
The following functions are provided:
fwnode_property_present()
fwnode_property_read_u8()
fwnode_property_read_u16()
fwnode_property_read_u32()
fwnode_property_read_u64()
fwnode_property_read_string()
fwnode_property_read_u8_array()
fwnode_property_read_u16_array()
fwnode_property_read_u32_array()
fwnode_property_read_u64_array()
fwnode_property_read_string_array()
in analogy with the corresponding functions for struct device added
previously. For all of them, the first argument is a pointer to struct
fwnode_handle (new type) that allows a device description object
(depending on what platform firmware interface is in use) to be
obtained.
Add a new macro device_for_each_child_node() for iterating over the
children of the device description object associated with a given
device and a new function device_get_child_node_count() returning the
number of a given device's child nodes.
The interface covers both ACPI and Device Trees.
Suggested-by: Grant Likely <grant.likely@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index f59cbf8..a361f43 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -27,6 +27,7 @@
#define __ACPI_BUS_H__
#include <linux/device.h>
+#include <linux/property.h>
/* TBD: Make dynamic */
#define ACPI_MAX_HANDLES 10
@@ -348,6 +349,7 @@
struct acpi_device {
int device_type;
acpi_handle handle; /* no handle for fixed hardware */
+ struct fwnode_handle fwnode;
struct acpi_device *parent;
struct list_head children;
struct list_head node;
@@ -372,6 +374,21 @@
void (*remove)(struct acpi_device *);
};
+static inline bool is_acpi_node(struct fwnode_handle *fwnode)
+{
+ return fwnode && fwnode->type == FWNODE_ACPI;
+}
+
+static inline struct acpi_device *acpi_node(struct fwnode_handle *fwnode)
+{
+ return fwnode ? container_of(fwnode, struct acpi_device, fwnode) : NULL;
+}
+
+static inline struct fwnode_handle *acpi_fwnode_handle(struct acpi_device *adev)
+{
+ return &adev->fwnode;
+}
+
static inline void *acpi_driver_data(struct acpi_device *d)
{
return d->driver_data;
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 38296d6..5b88022 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -440,6 +440,23 @@
#define ACPI_COMPANION_SET(dev, adev) do { } while (0)
#define ACPI_HANDLE(dev) (NULL)
+struct fwnode_handle;
+
+static inline bool is_acpi_node(struct fwnode_handle *fwnode)
+{
+ return false;
+}
+
+static inline struct acpi_device *acpi_node(struct fwnode_handle *fwnode)
+{
+ return NULL;
+}
+
+static inline struct fwnode_handle *acpi_fwnode_handle(struct acpi_device *adev)
+{
+ return NULL;
+}
+
static inline const char *acpi_dev_name(struct acpi_device *adev)
{
return NULL;
@@ -681,6 +698,9 @@
enum dev_prop_type proptype, void *val);
int acpi_dev_prop_read(struct acpi_device *adev, const char *propname,
enum dev_prop_type proptype, void *val, size_t nval);
+
+struct acpi_device *acpi_get_next_child(struct device *dev,
+ struct acpi_device *child);
#else
static inline int acpi_dev_get_property(struct acpi_device *adev,
const char *name, acpi_object_type type,
@@ -725,6 +745,12 @@
return -ENXIO;
}
+static inline struct acpi_device *acpi_get_next_child(struct device *dev,
+ struct acpi_device *child)
+{
+ return NULL;
+}
+
#endif
#endif /*_LINUX_ACPI_H*/
diff --git a/include/linux/of.h b/include/linux/of.h
index ce9f6a2..cf79be1 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -50,6 +50,7 @@
const char *type;
phandle phandle;
const char *full_name;
+ struct fwnode_handle fwnode;
struct property *properties;
struct property *deadprops; /* removed properties */
@@ -80,6 +81,7 @@
static inline void of_node_init(struct device_node *node)
{
kobject_init(&node->kobj, &of_node_ktype);
+ node->fwnode.type = FWNODE_OF;
}
/* true when node is initialized */
@@ -115,6 +117,16 @@
extern struct device_node *of_stdout;
extern raw_spinlock_t devtree_lock;
+static inline bool is_of_node(struct fwnode_handle *fwnode)
+{
+ return fwnode && fwnode->type == FWNODE_OF;
+}
+
+static inline struct device_node *of_node(struct fwnode_handle *fwnode)
+{
+ return fwnode ? container_of(fwnode, struct device_node, fwnode) : NULL;
+}
+
static inline bool of_have_populated_dt(void)
{
return of_allnodes != NULL;
@@ -360,6 +372,16 @@
#else /* CONFIG_OF */
+static inline bool is_of_node(struct fwnode_handle *fwnode)
+{
+ return false;
+}
+
+static inline struct device_node *of_node(struct fwnode_handle *fwnode)
+{
+ return NULL;
+}
+
static inline const char* of_node_full_name(const struct device_node *np)
{
return "<no-node>";
diff --git a/include/linux/property.h b/include/linux/property.h
index 9242fb0..a6a3d98 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -40,6 +40,46 @@
int device_property_read_string(struct device *dev, const char *propname,
const char **val);
+enum fwnode_type {
+ FWNODE_INVALID = 0,
+ FWNODE_OF,
+ FWNODE_ACPI,
+};
+
+struct fwnode_handle {
+ enum fwnode_type type;
+};
+
+bool fwnode_property_present(struct fwnode_handle *fwnode, const char *propname);
+int fwnode_property_read_u8_array(struct fwnode_handle *fwnode,
+ const char *propname, u8 *val,
+ size_t nval);
+int fwnode_property_read_u16_array(struct fwnode_handle *fwnode,
+ const char *propname, u16 *val,
+ size_t nval);
+int fwnode_property_read_u32_array(struct fwnode_handle *fwnode,
+ const char *propname, u32 *val,
+ size_t nval);
+int fwnode_property_read_u64_array(struct fwnode_handle *fwnode,
+ const char *propname, u64 *val,
+ size_t nval);
+int fwnode_property_read_string_array(struct fwnode_handle *fwnode,
+ const char *propname, const char **val,
+ size_t nval);
+int fwnode_property_read_string(struct fwnode_handle *fwnode,
+ const char *propname, const char **val);
+
+struct fwnode_handle *device_get_next_child_node(struct device *dev,
+ struct fwnode_handle *child);
+
+#define device_for_each_child_node(dev, child) \
+ for (child = device_get_next_child_node(dev, NULL); child; \
+ child = device_get_next_child_node(dev, child))
+
+void fwnode_handle_put(struct fwnode_handle *fwnode);
+
+unsigned int device_get_child_node_count(struct device *dev);
+
static inline bool device_property_read_bool(struct device *dev,
const char *propname)
{
@@ -70,4 +110,34 @@
return device_property_read_u64_array(dev, propname, val, 1);
}
+static inline bool fwnode_property_read_bool(struct fwnode_handle *fwnode,
+ const char *propname)
+{
+ return fwnode_property_present(fwnode, propname);
+}
+
+static inline int fwnode_property_read_u8(struct fwnode_handle *fwnode,
+ const char *propname, u8 *val)
+{
+ return fwnode_property_read_u8_array(fwnode, propname, val, 1);
+}
+
+static inline int fwnode_property_read_u16(struct fwnode_handle *fwnode,
+ const char *propname, u16 *val)
+{
+ return fwnode_property_read_u16_array(fwnode, propname, val, 1);
+}
+
+static inline int fwnode_property_read_u32(struct fwnode_handle *fwnode,
+ const char *propname, u32 *val)
+{
+ return fwnode_property_read_u32_array(fwnode, propname, val, 1);
+}
+
+static inline int fwnode_property_read_u64(struct fwnode_handle *fwnode,
+ const char *propname, u64 *val)
+{
+ return fwnode_property_read_u64_array(fwnode, propname, val, 1);
+}
+
#endif /* _LINUX_PROPERTY_H_ */