of: Constify struct device_node function arguments

Functions which don't change the refcount or otherwise modify struct
device_node can make struct device_node const.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20241010-dt-const-v1-3-87a51f558425@kernel.org
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>

Author: robherring

drivers/of/address.c

@@ -147,7 +147,7 @@ static unsigned int of_bus_pci_get_flags(const __be32 *addr)
  * PCI bus specific translator
  */
 
-static bool of_node_is_pcie(struct device_node *np)
+static bool of_node_is_pcie(const struct device_node *np)
 {
 	bool is_pcie = of_node_name_eq(np, "pcie");
 
@@ -230,8 +230,8 @@ static int __of_address_resource_bounds(struct resource *r, u64 start, u64 size)
  * To guard against that we try to register the IO range first.
  * If that fails we know that pci_address_to_pio() will do too.
  */
-int of_pci_range_to_resource(struct of_pci_range *range,
-			     struct device_node *np, struct resource *res)
+int of_pci_range_to_resource(const struct of_pci_range *range,
+			     const struct device_node *np, struct resource *res)
 {
 	u64 start;
 	int err;
@@ -399,7 +399,7 @@ static struct of_bus *of_match_bus(struct device_node *np)
 	return NULL;
 }
 
-static int of_empty_ranges_quirk(struct device_node *np)
+static int of_empty_ranges_quirk(const struct device_node *np)
 {
 	if (IS_ENABLED(CONFIG_PPC)) {
 		/* To save cycles, we cache the result for global "Mac" setting */
@@ -1030,7 +1030,7 @@ EXPORT_SYMBOL_GPL(of_dma_is_coherent);
  * This is currently only enabled on builds that support Apple ARM devices, as
  * an optimization.
  */
-static bool of_mmio_is_nonposted(struct device_node *np)
+static bool of_mmio_is_nonposted(const struct device_node *np)
 {
 	if (!IS_ENABLED(CONFIG_ARCH_APPLE))
 		return false;

drivers/of/base.c

@@ -771,7 +771,7 @@ struct device_node *of_get_child_by_name(const struct device_node *node,
 }
 EXPORT_SYMBOL(of_get_child_by_name);
 
-struct device_node *__of_find_node_by_path(struct device_node *parent,
+struct device_node *__of_find_node_by_path(const struct device_node *parent,
 						const char *path)
 {
 	struct device_node *child;
@@ -1840,7 +1840,7 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
  *
  * Return: The alias id if found.
  */
-int of_alias_get_id(struct device_node *np, const char *stem)
+int of_alias_get_id(const struct device_node *np, const char *stem)
 {
 	struct alias_prop *app;
 	int id = -ENODEV;
@@ -1898,7 +1898,7 @@ EXPORT_SYMBOL_GPL(of_alias_get_highest_id);
  *
  * Return: TRUE if console successfully setup. Otherwise return FALSE.
  */
-bool of_console_check(struct device_node *dn, char *name, int index)
+bool of_console_check(const struct device_node *dn, char *name, int index)
 {
 	if (!dn || dn != of_stdout || console_set_on_cmdline)
 		return false;
@@ -1986,7 +1986,7 @@ int of_find_last_cache_level(unsigned int cpu)
  *
  * Return: 0 on success or a standard error code on failure.
  */
-int of_map_id(struct device_node *np, u32 id,
+int of_map_id(const struct device_node *np, u32 id,
 	       const char *map_name, const char *map_mask_name,
 	       struct device_node **target, u32 *id_out)
 {

drivers/of/cpu.c

@@ -188,7 +188,7 @@ EXPORT_SYMBOL(of_cpu_node_to_id);
  * Return: An idle state node if found at @index. The refcount is incremented
  * for it, so call of_node_put() on it when done. Returns NULL if not found.
  */
-struct device_node *of_get_cpu_state_node(struct device_node *cpu_node,
+struct device_node *of_get_cpu_state_node(const struct device_node *cpu_node,
 					  int index)
 {
 	struct of_phandle_args args;

drivers/of/irq.c

@@ -720,7 +720,7 @@ struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 id,
  * Returns: the MSI domain for this device (or NULL on failure).
  */
 struct irq_domain *of_msi_get_domain(struct device *dev,
-				     struct device_node *np,
+				     const struct device_node *np,
 				     enum irq_domain_bus_token token)
 {
 	struct of_phandle_iterator it;
@@ -742,7 +742,7 @@ EXPORT_SYMBOL_GPL(of_msi_get_domain);
  * @dev: device structure to associate with an MSI irq domain
  * @np: device node for that device
  */
-void of_msi_configure(struct device *dev, struct device_node *np)
+void of_msi_configure(struct device *dev, const struct device_node *np)
 {
 	dev_set_msi_domain(dev,
 			   of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI));

drivers/of/of_private.h

@@ -127,7 +127,7 @@ void __of_prop_free(struct property *prop);
 struct device_node *__of_node_dup(const struct device_node *np,
 				  const char *full_name);
 
-struct device_node *__of_find_node_by_path(struct device_node *parent,
+struct device_node *__of_find_node_by_path(const struct device_node *parent,
 						const char *path);
 struct device_node *__of_find_node_by_full_path(struct device_node *node,
 						const char *path);

drivers/of/overlay.c

@@ -398,7 +398,7 @@ static int add_changeset_property(struct overlay_changeset *ovcs,
  * invalid @overlay.
  */
 static int add_changeset_node(struct overlay_changeset *ovcs,
-		struct target *target, struct device_node *node)
+		struct target *target, const struct device_node *node)
 {
 	const char *node_kbasename;
 	const __be32 *phandle;
@@ -675,8 +675,8 @@ static int build_changeset(struct overlay_changeset *ovcs)
  * 1) "target" property containing the phandle of the target
  * 2) "target-path" property containing the path of the target
  */
-static struct device_node *find_target(struct device_node *info_node,
-				       struct device_node *target_base)
+static struct device_node *find_target(const struct device_node *info_node,
+				       const struct device_node *target_base)
 {
 	struct device_node *node;
 	char *target_path;
@@ -735,7 +735,7 @@ static struct device_node *find_target(struct device_node *info_node,
  * init_overlay_changeset() must call free_overlay_changeset().
  */
 static int init_overlay_changeset(struct overlay_changeset *ovcs,
-				  struct device_node *target_base)
+				  const struct device_node *target_base)
 {
 	struct device_node *node, *overlay_node;
 	struct fragment *fragment;
@@ -910,7 +910,7 @@ static void free_overlay_changeset(struct overlay_changeset *ovcs)
  */
 
 static int of_overlay_apply(struct overlay_changeset *ovcs,
-			    struct device_node *base)
+			    const struct device_node *base)
 {
 	int ret = 0, ret_revert, ret_tmp;
 
@@ -978,7 +978,7 @@ static int of_overlay_apply(struct overlay_changeset *ovcs,
  */
 
 int of_overlay_fdt_apply(const void *overlay_fdt, u32 overlay_fdt_size,
-			 int *ret_ovcs_id, struct device_node *base)
+			 int *ret_ovcs_id, const struct device_node *base)
 {
 	void *new_fdt;
 	void *new_fdt_align;
@@ -1074,7 +1074,7 @@ EXPORT_SYMBOL_GPL(of_overlay_fdt_apply);
  *
  * Returns 1 if @np is @tree or is contained in @tree, else 0
  */
-static int find_node(struct device_node *tree, struct device_node *np)
+static int find_node(const struct device_node *tree, struct device_node *np)
 {
 	if (tree == np)
 		return 1;

drivers/of/resolver.c

@@ -147,8 +147,8 @@ static int node_name_cmp(const struct device_node *dn1,
  * of offsets of the phandle reference(s) within the respective property
  * value(s).  The values at these offsets will be fixed up.
  */
-static int adjust_local_phandle_references(struct device_node *local_fixups,
-		struct device_node *overlay, int phandle_delta)
+static int adjust_local_phandle_references(const struct device_node *local_fixups,
+		const struct device_node *overlay, int phandle_delta)
 {
 	struct device_node *overlay_child;
 	struct property *prop_fix, *prop;

include/linux/of.h

@@ -357,7 +357,7 @@ extern struct device_node *of_get_cpu_node(int cpu, unsigned int *thread);
 extern struct device_node *of_cpu_device_node_get(int cpu);
 extern int of_cpu_node_to_id(struct device_node *np);
 extern struct device_node *of_get_next_cpu_node(struct device_node *prev);
-extern struct device_node *of_get_cpu_state_node(struct device_node *cpu_node,
+extern struct device_node *of_get_cpu_state_node(const struct device_node *cpu_node,
 						 int index);
 extern u64 of_get_cpu_hwid(struct device_node *cpun, unsigned int thread);
 
@@ -395,7 +395,7 @@ extern int of_phandle_iterator_args(struct of_phandle_iterator *it,
 				    int size);
 
 extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align));
-extern int of_alias_get_id(struct device_node *np, const char *stem);
+extern int of_alias_get_id(const struct device_node *np, const char *stem);
 extern int of_alias_get_highest_id(const char *stem);
 
 bool of_machine_compatible_match(const char *const *compats);
@@ -446,9 +446,9 @@ const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
  */
 const char *of_prop_next_string(struct property *prop, const char *cur);
 
-bool of_console_check(struct device_node *dn, char *name, int index);
+bool of_console_check(const struct device_node *dn, char *name, int index);
 
-int of_map_id(struct device_node *np, u32 id,
+int of_map_id(const struct device_node *np, u32 id,
 	       const char *map_name, const char *map_mask_name,
 	       struct device_node **target, u32 *id_out);
 
@@ -871,7 +871,7 @@ static inline void of_property_clear_flag(struct property *p, unsigned long flag
 {
 }
 
-static inline int of_map_id(struct device_node *np, u32 id,
+static inline int of_map_id(const struct device_node *np, u32 id,
 			     const char *map_name, const char *map_mask_name,
 			     struct device_node **target, u32 *id_out)
 {
@@ -1734,7 +1734,7 @@ struct of_overlay_notify_data {
 #ifdef CONFIG_OF_OVERLAY
 
 int of_overlay_fdt_apply(const void *overlay_fdt, u32 overlay_fdt_size,
-			 int *ovcs_id, struct device_node *target_base);
+			 int *ovcs_id, const struct device_node *target_base);
 int of_overlay_remove(int *ovcs_id);
 int of_overlay_remove_all(void);
 
@@ -1744,7 +1744,7 @@ int of_overlay_notifier_unregister(struct notifier_block *nb);
 #else
 
 static inline int of_overlay_fdt_apply(const void *overlay_fdt, u32 overlay_fdt_size,
-				       int *ovcs_id, struct device_node *target_base)
+				       int *ovcs_id, const struct device_node *target_base)
 {
 	return -ENOTSUPP;
 }

include/linux/of_address.h

@@ -83,8 +83,8 @@ extern struct of_pci_range *of_pci_range_parser_one(
 					struct of_pci_range *range);
 extern int of_pci_address_to_resource(struct device_node *dev, int bar,
 				      struct resource *r);
-extern int of_pci_range_to_resource(struct of_pci_range *range,
-				    struct device_node *np,
+extern int of_pci_range_to_resource(const struct of_pci_range *range,
+				    const struct device_node *np,
 				    struct resource *res);
 extern int of_range_to_resource(struct device_node *np, int index,
 				struct resource *res);

include/linux/of_irq.h

@@ -48,12 +48,12 @@ extern int of_irq_to_resource_table(struct device_node *dev,
 		struct resource *res, int nr_irqs);
 extern struct device_node *of_irq_find_parent(struct device_node *child);
 extern struct irq_domain *of_msi_get_domain(struct device *dev,
-					    struct device_node *np,
+					    const struct device_node *np,
 					    enum irq_domain_bus_token token);
 extern struct irq_domain *of_msi_map_get_device_domain(struct device *dev,
 							u32 id,
 							u32 bus_token);
-extern void of_msi_configure(struct device *dev, struct device_node *np);
+extern void of_msi_configure(struct device *dev, const struct device_node *np);
 u32 of_msi_map_id(struct device *dev, struct device_node *msi_np, u32 id_in);
 #else
 static inline void of_irq_init(const struct of_device_id *matches)