[PATCH 03/15] ACPI / property: Add fwnode_get_next_child_node()

Sakari Ailus
2017-01-27T16:08:11Z

From: Mika Westerberg <mika.westerberg@linux.intel.com>

The ACPI _DSD hierarchical data extension [1] makes it possible to have
hierarchies deeper than one level in similar way than DT allows. These
"subsubnodes" have not been accessible because device property
implementation only provides device_get_next_child_node() that is limited
to direct descendants of a device.

We need this ability in order support things like remote endpoints
currently supported in DT with of_graph_* APIs.

Modify acpi_get_next_subnode() to accept fwnode handle instead and update
callers accordingly. Also add a new function fwnode_get_next_child_node()
that works directly with fwnodes and modify device_get_next_child_node() to
call it directly. While there add a macro fwnode_for_each_child_node()
analogous to the current device_for_each_child_node() but it works with
fwnodes instead of devices.

[1] http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.pdf

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
---
drivers/acpi/property.c | 27 +++++++++++++++++----------
drivers/base/property.c | 38 ++++++++++++++++++++++++++++++--------
include/linux/acpi.h | 8 ++++----
include/linux/property.h | 6 ++++++
4 files changed, 57 insertions(+), 22 deletions(-)

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 65a0606..09424ef 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -879,21 +879,22 @@ int acpi_node_prop_read(struct fwnode_handle *fwnode, const char *propname,
}

/**
- * acpi_get_next_subnode - Return the next child node handle for a device.
- * @dev: Device to find the next child node for.
+ * acpi_get_next_subnode - Return the next child node handle for a fwnode
+ * @fwnode: Firmware node to find the next child node for.
* @child: Handle to one of the device's child nodes or a null handle.
*/
-struct fwnode_handle *acpi_get_next_subnode(struct device *dev,
+struct fwnode_handle *acpi_get_next_subnode(struct fwnode_handle *fwnode,
struct fwnode_handle *child)
{
- struct acpi_device *adev = ACPI_COMPANION(dev);
+ struct acpi_device *adev = to_acpi_device_node(fwnode);
struct list_head *head, *next;

- if (!adev)
- return NULL;
-
if (!child || child->type == FWNODE_ACPI) {
- head = &adev->children;
+ if (adev)
+ head = &adev->children;
+ else
+ goto nondev;
+
if (list_empty(head))
goto nondev;

@@ -902,7 +903,6 @@ struct fwnode_handle *acpi_get_next_subnode(struct device *dev,
next = adev->node.next;
if (next == head) {
child = NULL;
- adev = ACPI_COMPANION(dev);
goto nondev;
}
adev = list_entry(next, struct acpi_device, node);
@@ -914,9 +914,16 @@ struct fwnode_handle *acpi_get_next_subnode(struct device *dev,

nondev:
if (!child || child->type == FWNODE_ACPI_DATA) {
+ struct acpi_data_node *data = to_acpi_data_node(fwnode);
struct acpi_data_node *dn;

- head = &adev->data.subnodes;
+ if (adev)
+ head = &adev->data.subnodes;
+ else if (data)
+ head = &data->data.subnodes;
+ else
+ return NULL;
+
if (list_empty(head))
return NULL;

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 384998a..15403f7 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -892,24 +892,46 @@ struct fwnode_handle *fwnode_get_parent(struct fwnode_handle *fwnode)
EXPORT_SYMBOL_GPL(fwnode_get_parent);

/**
- * device_get_next_child_node - Return the next child node handle for a device
- * @dev: Device to find the next child node for.
- * @child: Handle to one of the device's child nodes or a null handle.
+ * fwnode_get_next_child_node - Return the next child node handle for a node
+ * @fwnode: Firmware node to find the next child node for.
+ * @child: Handle to one of the node's child nodes or a %NULL handle.
*/
-struct fwnode_handle *device_get_next_child_node(struct device *dev,
+struct fwnode_handle *fwnode_get_next_child_node(struct fwnode_handle *fwnode,
struct fwnode_handle *child)
{
- if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
+ if (is_of_node(fwnode)) {
struct device_node *node;

- node = of_get_next_available_child(dev->of_node, to_of_node(child));
+ node = of_get_next_available_child(to_of_node(fwnode),
+ to_of_node(child));
if (node)
return &node->fwnode;
- } else if (IS_ENABLED(CONFIG_ACPI)) {
- return acpi_get_next_subnode(dev, child);
+ } else if (is_acpi_node(fwnode)) {
+ return acpi_get_next_subnode(fwnode, child);
}
+
return NULL;
}
+EXPORT_SYMBOL_GPL(fwnode_get_next_child_node);
+
+/**
+ * device_get_next_child_node - Return the next child node handle for a device
+ * @dev: Device to find the next child node for.
+ * @child: Handle to one of the device's child nodes or a null handle.
+ */
+struct fwnode_handle *device_get_next_child_node(struct device *dev,
+ struct fwnode_handle *child)
+{
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+ struct fwnode_handle *fwnode = NULL;
+
+ if (dev->of_node)
+ fwnode = &dev->of_node->fwnode;
+ else if (adev)
+ fwnode = acpi_fwnode_handle(adev);
+
+ return fwnode_get_next_child_node(fwnode, child);
+}
EXPORT_SYMBOL_GPL(device_get_next_child_node);

/**
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 868f923..f6f8655 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -999,8 +999,8 @@ int acpi_node_prop_read(struct fwnode_handle *fwnode, const char *propname,
int acpi_dev_prop_read(struct acpi_device *adev, const char *propname,
enum dev_prop_type proptype, void *val, size_t nval);

-struct fwnode_handle *acpi_get_next_subnode(struct device *dev,
- struct fwnode_handle *subnode);
+struct fwnode_handle *acpi_get_next_subnode(struct fwnode_handle *fwnode,
+ struct fwnode_handle *child);
struct fwnode_handle *acpi_node_get_parent(struct fwnode_handle *fwnode);

struct acpi_probe_entry;
@@ -1118,8 +1118,8 @@ static inline int acpi_dev_prop_read(struct acpi_device *adev,
return -ENXIO;
}

-static inline struct fwnode_handle *acpi_get_next_subnode(struct device *dev,
- struct fwnode_handle *subnode)
+static inline struct fwnode_handle *
+acpi_get_next_subnode(struct fwnode_handle *fwnode, struct fwnode_handle *child)
{
return NULL;
}
diff --git a/include/linux/property.h b/include/linux/property.h
index 85060bf..a3d4f52 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -71,6 +71,12 @@ int fwnode_property_match_string(struct fwnode_handle *fwnode,
const char *propname, const char *string);

struct fwnode_handle *fwnode_get_parent(struct fwnode_handle *fwnode);
+struct fwnode_handle *fwnode_get_next_child_node(struct fwnode_handle *fwnode,
+ struct fwnode_handle *child);
+
+#define fwnode_for_each_child_node(fwnode, child) \
+ for (child = fwnode_get_next_child_node(fwnode, NULL); child; \
+ child = fwnode_get_next_child_node(fwnode, child))

struct fwnode_handle *device_get_next_child_node(struct device *dev,
struct fwnode_handle *child);
--
2.7.4