[v5,2/4] device property: Add fwnode_is_compatible() and device_is_compatible() helpers

Commit Message

Jun Li Nov. 3, 2020, 11:40 a.m. UTC

From: Heikki Krogerus <[e-mail]>

Since there are also some ACPI platforms where the
"compatible" property is used, introducing a generic helper
function fwnode_is_compatible() that can be used with
DT, ACPI and swnodes, and a wrapper function
device_is_compatible() with it.

The function calls of_device_is_comaptible() with OF nodes,
and with ACPI and swnodes it matches the given string
against the "compatible" string property array.

Signed-off-by: Heikki Krogerus <[e-mail]>
Signed-off-by: Li Jun <[e-mail]>
---
change for v5
- A minor change to move the function return valure description
  to a new paragraph.

New patch for v4.

 drivers/base/property.c  | 39 +++++++++++++++++++++++++++++++++++++++
 include/linux/property.h |  2 ++
 2 files changed, 41 insertions(+)

Patch

diff --git a/drivers/base/property.c b/drivers/base/property.c
index d58aa98..d1c1f30 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -1184,3 +1184,42 @@  const void *device_get_match_data(struct device *dev)
 	return fwnode_call_ptr_op(dev_fwnode(dev), device_get_match_data, dev);
 }
 EXPORT_SYMBOL_GPL(device_get_match_data);
+
+/**
+ * fwnode_is_compatible - Check does fwnode have the given compatible string
+ * @fwnode: fwnode with the "compatible" property
+ * @compat: The compatible string
+ *
+ * Match the compatible strings of @fwnode against @compat.
+ *
+ * Returns positive value on match, and 0 when no matching compatible
+ * string is found.
+ */
+int fwnode_is_compatible(struct fwnode_handle *fwnode, const char *compat)
+{
+	int ret;
+
+	if (is_of_node(fwnode))
+		return of_device_is_compatible(to_of_node(fwnode), compat);
+
+	ret = fwnode_property_match_string(fwnode, "compatible", compat);
+
+	return ret < 0 ? 0 : 1;
+}
+EXPORT_SYMBOL_GPL(fwnode_is_compatible);
+
+/**
+ * device_is_compatible - Check does a device have the given compatible string
+ * @dev: Device with the "compatible" property
+ * @compat: The compatible string
+ *
+ * Match the compatible strings of @dev against @compat.
+ *
+ * Returns positive value on match, and 0 when no matching compatible
+ * string is found.
+ */
+int device_is_compatible(struct device *dev, const char *compat)
+{
+	return fwnode_is_compatible(dev_fwnode(dev), compat);
+}
+EXPORT_SYMBOL_GPL(device_is_compatible);
diff --git a/include/linux/property.h b/include/linux/property.h
index 9f805c4..42c1d99 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -48,6 +48,7 @@  int device_property_read_string(struct device *dev, const char *propname,
 				const char **val);
 int device_property_match_string(struct device *dev,
 				 const char *propname, const char *string);
+int device_is_compatible(struct device *dev, const char *compat);
 
 bool fwnode_device_is_available(const struct fwnode_handle *fwnode);
 bool fwnode_property_present(const struct fwnode_handle *fwnode,
@@ -117,6 +118,7 @@  struct fwnode_handle *fwnode_handle_get(struct fwnode_handle *fwnode);
 void fwnode_handle_put(struct fwnode_handle *fwnode);
 
 int fwnode_irq_get(struct fwnode_handle *fwnode, unsigned int index);
+int fwnode_is_compatible(struct fwnode_handle *fwnode, const char *compat);
 
 unsigned int device_get_child_node_count(struct device *dev);