Implement a set of functions to manipulate properties in a live device tree:
* ofnode_set_property() to set generic properties of a node * ofnode_write_string() to set string properties of a node * ofnode_set_enabled() to either enable or disable a node
Signed-off-by: Mario Six mario.six@gdsys.cc
---
v1 -> v2: * Fix potential NULL pointer dereference in ofnode_write_property
--- drivers/core/ofnode.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++ include/dm/ofnode.h | 37 ++++++++++++++++++++++++++++++++ 2 files changed, 95 insertions(+)
diff --git a/drivers/core/ofnode.c b/drivers/core/ofnode.c index 5909a25f85..a55aa75e5b 100644 --- a/drivers/core/ofnode.c +++ b/drivers/core/ofnode.c @@ -687,3 +687,61 @@ u64 ofnode_translate_address(ofnode node, const fdt32_t *in_addr) else return fdt_translate_address(gd->fdt_blob, ofnode_to_offset(node), in_addr); } + +#ifdef CONFIG_OF_LIVE +int ofnode_write_property(ofnode node, const char *propname, int len, + const void *value) +{ + const struct device_node *np = ofnode_to_np(node); + struct property *pp; + struct property *pp_last = NULL; + struct property *new; + + if (!np) + return -EINVAL; + + for (pp = np->properties; pp; pp = pp->next) { + if (strcmp(pp->name, propname) == 0) { + /* Property exists -> change value */ + pp->value = (void *)value; + pp->length = len; + return 0; + } + pp_last = pp; + } + + if (!pp_last) + return -ENOENT; + + /* Property does not exist -> append new property */ + new = malloc(sizeof(struct property)); + + new->name = strdup(propname); + new->value = malloc(len); + memcpy(new->value, value, len); + new->length = len; + new->next = NULL; + + pp_last->next = new; + + return 0; +} + +int ofnode_write_string(ofnode node, const char *propname, const char *value) +{ + assert(ofnode_valid(node)); + debug("%s: %s = %s", __func__, propname, value); + + return ofnode_write_property(node, propname, strlen(value) + 1, value); +} + +int ofnode_set_enabled(ofnode node, bool value) +{ + assert(ofnode_valid(node)); + + if (value) + return ofnode_write_string(node, "status", "okay"); + else + return ofnode_write_string(node, "status", "disable"); +} +#endif diff --git a/include/dm/ofnode.h b/include/dm/ofnode.h index 0d008404f9..9224d583fc 100644 --- a/include/dm/ofnode.h +++ b/include/dm/ofnode.h @@ -681,4 +681,41 @@ int ofnode_read_resource_byname(ofnode node, const char *name, * @return the translated address; OF_BAD_ADDR on error */ u64 ofnode_translate_address(ofnode node, const fdt32_t *in_addr); + +/** + * ofnode_write_property() - Set a property of a ofnode + * + * @node: The node for whose property should be set + * @propname: The name of the property to set + * @len: The length of the new value of the property + * @value: The new value of the property + * @return 0 if successful, -ve on error + */ +int ofnode_write_property(ofnode node, const char *propname, int len, + const void *value); + +/** + * ofnode_write_string() - Set a string property of a ofnode + * + * @node: The node for whose string property should be set + * @propname: The name of the string property to set + * @value: The new value of the string property + * @return 0 if successful, -ve on error + */ +int ofnode_write_string(ofnode node, const char *propname, const char *value); + +/** + * ofnode_set_enabled() - Enable or disable a device tree node given by its ofnode + * + * This function effectively sets the node's "status" property to either "okay" + * or "disable", hence making it available for driver model initialization or + * not. + * + * @node: The node to enable + * @value: Flag that tells the function to either disable or enable the + * node + * @return 0 if successful, -ve on error + */ +int ofnode_set_enabled(ofnode node, bool value); + #endif -- 2.16.1