[PATCH v7.2 7/7] device property: Get rid of struct fwnode_handle type field

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Instead of relying on the struct fwnode_handle type field, define
fwnode_operations structs for all separate types of fwnodes. To find out
the type, compare to the ops field to relevant ops structs.

This change has two benefits:

1. it avoids adding the type field to each and every instance of struct
fwnode_handle, thus saving memory and

2. makes the ops field the single factor that defines both the types of
the fwnode as well as defines the implementation of its operations,
decreasing the possibility of bugs when developing code dealing with
fwnode internals.

Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
changes since v7.1:

- Align backslashes in DECLARE_ACPI_FWNODE_OPS() macro.

 drivers/acpi/property.c   | 47 ++++++++++++++++++++++++++++-------------------
 drivers/acpi/scan.c       |  3 +--
 drivers/base/property.c   |  5 +++--
 drivers/of/property.c     |  1 +
 include/acpi/acpi_bus.h   | 19 +++++++++++++++----
 include/linux/acpi.h      |  8 ++------
 include/linux/fwnode.h    | 11 -----------
 include/linux/irqdomain.h |  4 +++-
 include/linux/of.h        |  3 +--
 kernel/irq/irqdomain.c    |  4 +++-
 10 files changed, 57 insertions(+), 48 deletions(-)

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 917c789..4d3d897 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -56,8 +56,7 @@ static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
 		return false;
 
 	dn->name = link->package.elements[0].string.pointer;
-	dn->fwnode.type = FWNODE_ACPI_DATA;
-	dn->fwnode.ops = &acpi_fwnode_ops;
+	dn->fwnode.ops = &acpi_data_fwnode_ops;
 	dn->parent = parent;
 	INIT_LIST_HEAD(&dn->data.subnodes);
 
@@ -469,10 +468,10 @@ EXPORT_SYMBOL_GPL(acpi_dev_get_property);
 
 static struct acpi_device_data *acpi_device_data_of_node(struct fwnode_handle *fwnode)
 {
-	if (fwnode->type == FWNODE_ACPI) {
+	if (is_acpi_device_node(fwnode)) {
 		struct acpi_device *adev = to_acpi_device_node(fwnode);
 		return &adev->data;
-	} else if (fwnode->type == FWNODE_ACPI_DATA) {
+	} else if (is_acpi_data_node(fwnode)) {
 		struct acpi_data_node *dn = to_acpi_data_node(fwnode);
 		return &dn->data;
 	}
@@ -903,7 +902,7 @@ struct fwnode_handle *acpi_get_next_subnode(struct fwnode_handle *fwnode,
 	struct acpi_device *adev = to_acpi_device_node(fwnode);
 	struct list_head *head, *next;
 
-	if (!child || child->type == FWNODE_ACPI) {
+	if (!child || is_acpi_device_node(child)) {
 		if (adev)
 			head = &adev->children;
 		else
@@ -927,7 +926,7 @@ struct fwnode_handle *acpi_get_next_subnode(struct fwnode_handle *fwnode,
 	}
 
  nondev:
-	if (!child || child->type == FWNODE_ACPI_DATA) {
+	if (!child || is_acpi_data_node(child)) {
 		struct acpi_data_node *data = to_acpi_data_node(fwnode);
 		struct acpi_data_node *dn;
 
@@ -1223,16 +1222,26 @@ static int acpi_fwnode_graph_parse_endpoint(struct fwnode_handle *fwnode,
 	return 0;
 }
 
-const struct fwnode_operations acpi_fwnode_ops = {
-	.device_is_available = acpi_fwnode_device_is_available,
-	.property_present = acpi_fwnode_property_present,
-	.property_read_int_array = acpi_fwnode_property_read_int_array,
-	.property_read_string_array = acpi_fwnode_property_read_string_array,
-	.get_parent = acpi_node_get_parent,
-	.get_next_child_node = acpi_get_next_subnode,
-	.get_named_child_node = acpi_fwnode_get_named_child_node,
-	.graph_get_next_endpoint = acpi_fwnode_graph_get_next_endpoint,
-	.graph_get_remote_endpoint = acpi_fwnode_graph_get_remote_endpoint,
-	.graph_get_port_parent = acpi_node_get_parent,
-	.graph_parse_endpoint = acpi_fwnode_graph_parse_endpoint,
-};
+#define DECLARE_ACPI_FWNODE_OPS(ops) \
+	const struct fwnode_operations ops = {				\
+		.device_is_available = acpi_fwnode_device_is_available, \
+		.property_present = acpi_fwnode_property_present,	\
+		.property_read_int_array =				\
+			acpi_fwnode_property_read_int_array,		\
+		.property_read_string_array =				\
+			acpi_fwnode_property_read_string_array,		\
+		.get_parent = acpi_node_get_parent,			\
+		.get_next_child_node = acpi_get_next_subnode,		\
+		.get_named_child_node = acpi_fwnode_get_named_child_node, \
+		.graph_get_next_endpoint =				\
+			acpi_fwnode_graph_get_next_endpoint,		\
+		.graph_get_remote_endpoint =				\
+			acpi_fwnode_graph_get_remote_endpoint,		\
+		.graph_get_port_parent = acpi_node_get_parent,		\
+		.graph_parse_endpoint = acpi_fwnode_graph_parse_endpoint, \
+	};								\
+	EXPORT_SYMBOL_GPL(ops)
+
+DECLARE_ACPI_FWNODE_OPS(acpi_device_fwnode_ops);
+DECLARE_ACPI_FWNODE_OPS(acpi_data_fwnode_ops);
+DECLARE_ACPI_FWNODE_OPS(acpi_static_fwnode_ops);
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index fe379a0..53e268b 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1435,8 +1435,7 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
 	device->device_type = type;
 	device->handle = handle;
 	device->parent = acpi_bus_get_parent(handle);
-	device->fwnode.type = FWNODE_ACPI;
-	device->fwnode.ops = &acpi_fwnode_ops;
+	device->fwnode.ops = &acpi_device_fwnode_ops;
 	acpi_set_device_status(device, sta);
 	acpi_device_get_busid(device);
 	acpi_set_pnp_ids(handle, &device->pnp, type);
diff --git a/drivers/base/property.c b/drivers/base/property.c
index 692007e..09770fc 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -25,9 +25,11 @@ struct property_set {
 	const struct property_entry *properties;
 };
 
+static const struct fwnode_operations pset_fwnode_ops;
+
 static inline bool is_pset_node(struct fwnode_handle *fwnode)
 {
-	return !IS_ERR_OR_NULL(fwnode) && fwnode->type == FWNODE_PDATA;
+	return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &pset_fwnode_ops;
 }
 
 static inline struct property_set *to_pset_node(struct fwnode_handle *fwnode)
@@ -900,7 +902,6 @@ int device_add_properties(struct device *dev,
 	if (IS_ERR(p))
 		return PTR_ERR(p);
 
-	p->fwnode.type = FWNODE_PDATA;
 	p->fwnode.ops = &pset_fwnode_ops;
 	set_secondary_fwnode(dev, &p->fwnode);
 	return 0;
diff --git a/drivers/of/property.c b/drivers/of/property.c
index c96389b..edd629b 100644
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -912,3 +912,4 @@ const struct fwnode_operations of_fwnode_ops = {
 	.graph_get_port_parent = of_fwnode_graph_get_port_parent,
 	.graph_parse_endpoint = of_fwnode_graph_parse_endpoint,
 };
+EXPORT_SYMBOL_GPL(of_fwnode_ops);
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 197f3ff..e724afc 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -394,15 +394,21 @@ struct acpi_data_node {
 	struct completion kobj_done;
 };
 
+extern const struct fwnode_operations acpi_device_fwnode_ops;
+extern const struct fwnode_operations acpi_data_fwnode_ops;
+extern const struct fwnode_operations acpi_static_fwnode_ops;
+
 static inline bool is_acpi_node(struct fwnode_handle *fwnode)
 {
-	return !IS_ERR_OR_NULL(fwnode) && (fwnode->type == FWNODE_ACPI
-		|| fwnode->type == FWNODE_ACPI_DATA);
+	return !IS_ERR_OR_NULL(fwnode) &&
+		(fwnode->ops == &acpi_device_fwnode_ops
+		 || fwnode->ops == &acpi_data_fwnode_ops);
 }
 
 static inline bool is_acpi_device_node(struct fwnode_handle *fwnode)
 {
-	return !IS_ERR_OR_NULL(fwnode) && fwnode->type == FWNODE_ACPI;
+	return !IS_ERR_OR_NULL(fwnode) &&
+		fwnode->ops == &acpi_device_fwnode_ops;
 }
 
 static inline struct acpi_device *to_acpi_device_node(struct fwnode_handle *fwnode)
@@ -413,7 +419,12 @@ static inline struct acpi_device *to_acpi_device_node(struct fwnode_handle *fwno
 
 static inline bool is_acpi_data_node(struct fwnode_handle *fwnode)
 {
-	return fwnode && fwnode->type == FWNODE_ACPI_DATA;
+	return fwnode && fwnode->ops == &acpi_data_fwnode_ops;
+}
+
+static inline bool is_acpi_static_node(struct fwnode_handle *fwnode)
+{
+	return fwnode && fwnode->ops == &acpi_static_fwnode_ops;
 }
 
 static inline struct acpi_data_node *to_acpi_data_node(struct fwnode_handle *fwnode)
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index b8f23c5..ad19760 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -56,9 +56,6 @@ static inline acpi_handle acpi_device_handle(struct acpi_device *adev)
 	acpi_fwnode_handle(adev) : NULL)
 #define ACPI_HANDLE(dev)		acpi_device_handle(ACPI_COMPANION(dev))
 
-
-extern const struct fwnode_operations acpi_fwnode_ops;
-
 static inline struct fwnode_handle *acpi_alloc_fwnode_static(void)
 {
 	struct fwnode_handle *fwnode;
@@ -67,15 +64,14 @@ static inline struct fwnode_handle *acpi_alloc_fwnode_static(void)
 	if (!fwnode)
 		return NULL;
 
-	fwnode->type = FWNODE_ACPI_STATIC;
-	fwnode->ops = &acpi_fwnode_ops;
+	fwnode->ops = &acpi_static_fwnode_ops;
 
 	return fwnode;
 }
 
 static inline void acpi_free_fwnode_static(struct fwnode_handle *fwnode)
 {
-	if (WARN_ON(!fwnode || fwnode->type != FWNODE_ACPI_STATIC))
+	if (WARN_ON(!fwnode || !is_acpi_static_node(fwnode)))
 		return;
 
 	kfree(fwnode);
diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h
index 9ab3754..e7ca4c5 100644
--- a/include/linux/fwnode.h
+++ b/include/linux/fwnode.h
@@ -14,20 +14,9 @@
 
 #include <linux/types.h>
 
-enum fwnode_type {
-	FWNODE_INVALID = 0,
-	FWNODE_OF,
-	FWNODE_ACPI,
-	FWNODE_ACPI_DATA,
-	FWNODE_ACPI_STATIC,
-	FWNODE_PDATA,
-	FWNODE_IRQCHIP
-};
-
 struct fwnode_operations;
 
 struct fwnode_handle {
-	enum fwnode_type type;
 	struct fwnode_handle *secondary;
 	const struct fwnode_operations *ops;
 };
diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index 9f36160..ee1910c 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -233,9 +233,11 @@ static inline struct fwnode_handle *of_node_to_fwnode(struct device_node *node)
 	return node ? &node->fwnode : NULL;
 }
 
+extern const struct fwnode_operations irqchip_fwnode_ops;
+
 static inline bool is_fwnode_irqchip(struct fwnode_handle *fwnode)
 {
-	return fwnode && fwnode->type == FWNODE_IRQCHIP;
+	return fwnode && fwnode->ops == &irqchip_fwnode_ops;
 }
 
 static inline
diff --git a/include/linux/of.h b/include/linux/of.h
index cdbfa88..6e39aa1 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -104,7 +104,6 @@ extern const struct fwnode_operations of_fwnode_ops;
 static inline void of_node_init(struct device_node *node)
 {
 	kobject_init(&node->kobj, &of_node_ktype);
-	node->fwnode.type = FWNODE_OF;
 	node->fwnode.ops = &of_fwnode_ops;
 }
 
@@ -152,7 +151,7 @@ void of_core_init(void);
 
 static inline bool is_of_node(const struct fwnode_handle *fwnode)
 {
-	return !IS_ERR_OR_NULL(fwnode) && fwnode->type == FWNODE_OF;
+	return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &of_fwnode_ops;
 }
 
 #define to_of_node(__fwnode)						\
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 31805f2..e746c42 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -31,6 +31,8 @@ struct irqchip_fwid {
 	void *data;
 };
 
+const struct fwnode_operations irqchip_fwnode_ops;
+
 /**
  * irq_domain_alloc_fwnode - Allocate a fwnode_handle suitable for
  *                           identifying an irq domain
@@ -55,7 +57,7 @@ struct fwnode_handle *irq_domain_alloc_fwnode(void *data)
 
 	fwid->name = name;
 	fwid->data = data;
-	fwid->fwnode.type = FWNODE_IRQCHIP;
+	fwid->fwnode.ops = &irqchip_fwnode_ops;
 	return &fwid->fwnode;
 }
 EXPORT_SYMBOL_GPL(irq_domain_alloc_fwnode);
-- 
2.7.4