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Diffstat (limited to 'drivers/of/property.c')
| -rw-r--r-- | drivers/of/property.c | 1478 |
1 files changed, 1478 insertions, 0 deletions
diff --git a/drivers/of/property.c b/drivers/of/property.c new file mode 100644 index 000000000..a411460d2 --- /dev/null +++ b/drivers/of/property.c @@ -0,0 +1,1478 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * drivers/of/property.c - Procedures for accessing and interpreting + * Devicetree properties and graphs. + * + * Initially created by copying procedures from drivers/of/base.c. This + * file contains the OF property as well as the OF graph interface + * functions. + * + * Paul Mackerras August 1996. + * Copyright (C) 1996-2005 Paul Mackerras. + * + * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner. + * {engebret|bergner}@us.ibm.com + * + * Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net + * + * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and + * Grant Likely. + */ + +#define pr_fmt(fmt) "OF: " fmt + +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_graph.h> +#include <linux/string.h> +#include <linux/moduleparam.h> + +#include "of_private.h" + +/** + * of_graph_is_present() - check graph's presence + * @node: pointer to device_node containing graph port + * + * Return: True if @node has a port or ports (with a port) sub-node, + * false otherwise. + */ +bool of_graph_is_present(const struct device_node *node) +{ + struct device_node *ports, *port; + + ports = of_get_child_by_name(node, "ports"); + if (ports) + node = ports; + + port = of_get_child_by_name(node, "port"); + of_node_put(ports); + of_node_put(port); + + return !!port; +} +EXPORT_SYMBOL(of_graph_is_present); + +/** + * of_property_count_elems_of_size - Count the number of elements in a property + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @elem_size: size of the individual element + * + * Search for a property in a device node and count the number of elements of + * size elem_size in it. + * + * Return: The number of elements on sucess, -EINVAL if the property does not + * exist or its length does not match a multiple of elem_size and -ENODATA if + * the property does not have a value. + */ +int of_property_count_elems_of_size(const struct device_node *np, + const char *propname, int elem_size) +{ + struct property *prop = of_find_property(np, propname, NULL); + + if (!prop) + return -EINVAL; + if (!prop->value) + return -ENODATA; + + if (prop->length % elem_size != 0) { + pr_err("size of %s in node %pOF is not a multiple of %d\n", + propname, np, elem_size); + return -EINVAL; + } + + return prop->length / elem_size; +} +EXPORT_SYMBOL_GPL(of_property_count_elems_of_size); + +/** + * of_find_property_value_of_size + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @min: minimum allowed length of property value + * @max: maximum allowed length of property value (0 means unlimited) + * @len: if !=NULL, actual length is written to here + * + * Search for a property in a device node and valid the requested size. + * + * Return: The property value on success, -EINVAL if the property does not + * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the + * property data is too small or too large. + * + */ +static void *of_find_property_value_of_size(const struct device_node *np, + const char *propname, u32 min, u32 max, size_t *len) +{ + struct property *prop = of_find_property(np, propname, NULL); + + if (!prop) + return ERR_PTR(-EINVAL); + if (!prop->value) + return ERR_PTR(-ENODATA); + if (prop->length < min) + return ERR_PTR(-EOVERFLOW); + if (max && prop->length > max) + return ERR_PTR(-EOVERFLOW); + + if (len) + *len = prop->length; + + return prop->value; +} + +/** + * of_property_read_u32_index - Find and read a u32 from a multi-value property. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @index: index of the u32 in the list of values + * @out_value: pointer to return value, modified only if no error. + * + * Search for a property in a device node and read nth 32-bit value from + * it. + * + * Return: 0 on success, -EINVAL if the property does not exist, + * -ENODATA if property does not have a value, and -EOVERFLOW if the + * property data isn't large enough. + * + * The out_value is modified only if a valid u32 value can be decoded. + */ +int of_property_read_u32_index(const struct device_node *np, + const char *propname, + u32 index, u32 *out_value) +{ + const u32 *val = of_find_property_value_of_size(np, propname, + ((index + 1) * sizeof(*out_value)), + 0, + NULL); + + if (IS_ERR(val)) + return PTR_ERR(val); + + *out_value = be32_to_cpup(((__be32 *)val) + index); + return 0; +} +EXPORT_SYMBOL_GPL(of_property_read_u32_index); + +/** + * of_property_read_u64_index - Find and read a u64 from a multi-value property. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @index: index of the u64 in the list of values + * @out_value: pointer to return value, modified only if no error. + * + * Search for a property in a device node and read nth 64-bit value from + * it. + * + * Return: 0 on success, -EINVAL if the property does not exist, + * -ENODATA if property does not have a value, and -EOVERFLOW if the + * property data isn't large enough. + * + * The out_value is modified only if a valid u64 value can be decoded. + */ +int of_property_read_u64_index(const struct device_node *np, + const char *propname, + u32 index, u64 *out_value) +{ + const u64 *val = of_find_property_value_of_size(np, propname, + ((index + 1) * sizeof(*out_value)), + 0, NULL); + + if (IS_ERR(val)) + return PTR_ERR(val); + + *out_value = be64_to_cpup(((__be64 *)val) + index); + return 0; +} +EXPORT_SYMBOL_GPL(of_property_read_u64_index); + +/** + * of_property_read_variable_u8_array - Find and read an array of u8 from a + * property, with bounds on the minimum and maximum array size. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_values: pointer to found values. + * @sz_min: minimum number of array elements to read + * @sz_max: maximum number of array elements to read, if zero there is no + * upper limit on the number of elements in the dts entry but only + * sz_min will be read. + * + * Search for a property in a device node and read 8-bit value(s) from + * it. + * + * dts entry of array should be like: + * ``property = /bits/ 8 <0x50 0x60 0x70>;`` + * + * Return: The number of elements read on success, -EINVAL if the property + * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW + * if the property data is smaller than sz_min or longer than sz_max. + * + * The out_values is modified only if a valid u8 value can be decoded. + */ +int of_property_read_variable_u8_array(const struct device_node *np, + const char *propname, u8 *out_values, + size_t sz_min, size_t sz_max) +{ + size_t sz, count; + const u8 *val = of_find_property_value_of_size(np, propname, + (sz_min * sizeof(*out_values)), + (sz_max * sizeof(*out_values)), + &sz); + + if (IS_ERR(val)) + return PTR_ERR(val); + + if (!sz_max) + sz = sz_min; + else + sz /= sizeof(*out_values); + + count = sz; + while (count--) + *out_values++ = *val++; + + return sz; +} +EXPORT_SYMBOL_GPL(of_property_read_variable_u8_array); + +/** + * of_property_read_variable_u16_array - Find and read an array of u16 from a + * property, with bounds on the minimum and maximum array size. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_values: pointer to found values. + * @sz_min: minimum number of array elements to read + * @sz_max: maximum number of array elements to read, if zero there is no + * upper limit on the number of elements in the dts entry but only + * sz_min will be read. + * + * Search for a property in a device node and read 16-bit value(s) from + * it. + * + * dts entry of array should be like: + * ``property = /bits/ 16 <0x5000 0x6000 0x7000>;`` + * + * Return: The number of elements read on success, -EINVAL if the property + * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW + * if the property data is smaller than sz_min or longer than sz_max. + * + * The out_values is modified only if a valid u16 value can be decoded. + */ +int of_property_read_variable_u16_array(const struct device_node *np, + const char *propname, u16 *out_values, + size_t sz_min, size_t sz_max) +{ + size_t sz, count; + const __be16 *val = of_find_property_value_of_size(np, propname, + (sz_min * sizeof(*out_values)), + (sz_max * sizeof(*out_values)), + &sz); + + if (IS_ERR(val)) + return PTR_ERR(val); + + if (!sz_max) + sz = sz_min; + else + sz /= sizeof(*out_values); + + count = sz; + while (count--) + *out_values++ = be16_to_cpup(val++); + + return sz; +} +EXPORT_SYMBOL_GPL(of_property_read_variable_u16_array); + +/** + * of_property_read_variable_u32_array - Find and read an array of 32 bit + * integers from a property, with bounds on the minimum and maximum array size. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_values: pointer to return found values. + * @sz_min: minimum number of array elements to read + * @sz_max: maximum number of array elements to read, if zero there is no + * upper limit on the number of elements in the dts entry but only + * sz_min will be read. + * + * Search for a property in a device node and read 32-bit value(s) from + * it. + * + * Return: The number of elements read on success, -EINVAL if the property + * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW + * if the property data is smaller than sz_min or longer than sz_max. + * + * The out_values is modified only if a valid u32 value can be decoded. + */ +int of_property_read_variable_u32_array(const struct device_node *np, + const char *propname, u32 *out_values, + size_t sz_min, size_t sz_max) +{ + size_t sz, count; + const __be32 *val = of_find_property_value_of_size(np, propname, + (sz_min * sizeof(*out_values)), + (sz_max * sizeof(*out_values)), + &sz); + + if (IS_ERR(val)) + return PTR_ERR(val); + + if (!sz_max) + sz = sz_min; + else + sz /= sizeof(*out_values); + + count = sz; + while (count--) + *out_values++ = be32_to_cpup(val++); + + return sz; +} +EXPORT_SYMBOL_GPL(of_property_read_variable_u32_array); + +/** + * of_property_read_u64 - Find and read a 64 bit integer from a property + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_value: pointer to return value, modified only if return value is 0. + * + * Search for a property in a device node and read a 64-bit value from + * it. + * + * Return: 0 on success, -EINVAL if the property does not exist, + * -ENODATA if property does not have a value, and -EOVERFLOW if the + * property data isn't large enough. + * + * The out_value is modified only if a valid u64 value can be decoded. + */ +int of_property_read_u64(const struct device_node *np, const char *propname, + u64 *out_value) +{ + const __be32 *val = of_find_property_value_of_size(np, propname, + sizeof(*out_value), + 0, + NULL); + + if (IS_ERR(val)) + return PTR_ERR(val); + + *out_value = of_read_number(val, 2); + return 0; +} +EXPORT_SYMBOL_GPL(of_property_read_u64); + +/** + * of_property_read_variable_u64_array - Find and read an array of 64 bit + * integers from a property, with bounds on the minimum and maximum array size. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_values: pointer to found values. + * @sz_min: minimum number of array elements to read + * @sz_max: maximum number of array elements to read, if zero there is no + * upper limit on the number of elements in the dts entry but only + * sz_min will be read. + * + * Search for a property in a device node and read 64-bit value(s) from + * it. + * + * Return: The number of elements read on success, -EINVAL if the property + * does not exist, -ENODATA if property does not have a value, and -EOVERFLOW + * if the property data is smaller than sz_min or longer than sz_max. + * + * The out_values is modified only if a valid u64 value can be decoded. + */ +int of_property_read_variable_u64_array(const struct device_node *np, + const char *propname, u64 *out_values, + size_t sz_min, size_t sz_max) +{ + size_t sz, count; + const __be32 *val = of_find_property_value_of_size(np, propname, + (sz_min * sizeof(*out_values)), + (sz_max * sizeof(*out_values)), + &sz); + + if (IS_ERR(val)) + return PTR_ERR(val); + + if (!sz_max) + sz = sz_min; + else + sz /= sizeof(*out_values); + + count = sz; + while (count--) { + *out_values++ = of_read_number(val, 2); + val += 2; + } + + return sz; +} +EXPORT_SYMBOL_GPL(of_property_read_variable_u64_array); + +/** + * of_property_read_string - Find and read a string from a property + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_string: pointer to null terminated return string, modified only if + * return value is 0. + * + * Search for a property in a device tree node and retrieve a null + * terminated string value (pointer to data, not a copy). + * + * Return: 0 on success, -EINVAL if the property does not exist, -ENODATA if + * property does not have a value, and -EILSEQ if the string is not + * null-terminated within the length of the property data. + * + * The out_string pointer is modified only if a valid string can be decoded. + */ +int of_property_read_string(const struct device_node *np, const char *propname, + const char **out_string) +{ + const struct property *prop = of_find_property(np, propname, NULL); + if (!prop) + return -EINVAL; + if (!prop->value) + return -ENODATA; + if (strnlen(prop->value, prop->length) >= prop->length) + return -EILSEQ; + *out_string = prop->value; + return 0; +} +EXPORT_SYMBOL_GPL(of_property_read_string); + +/** + * of_property_match_string() - Find string in a list and return index + * @np: pointer to node containing string list property + * @propname: string list property name + * @string: pointer to string to search for in string list + * + * This function searches a string list property and returns the index + * of a specific string value. + */ +int of_property_match_string(const struct device_node *np, const char *propname, + const char *string) +{ + const struct property *prop = of_find_property(np, propname, NULL); + size_t l; + int i; + const char *p, *end; + + if (!prop) + return -EINVAL; + if (!prop->value) + return -ENODATA; + + p = prop->value; + end = p + prop->length; + + for (i = 0; p < end; i++, p += l) { + l = strnlen(p, end - p) + 1; + if (p + l > end) + return -EILSEQ; + pr_debug("comparing %s with %s\n", string, p); + if (strcmp(string, p) == 0) + return i; /* Found it; return index */ + } + return -ENODATA; +} +EXPORT_SYMBOL_GPL(of_property_match_string); + +/** + * of_property_read_string_helper() - Utility helper for parsing string properties + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_strs: output array of string pointers. + * @sz: number of array elements to read. + * @skip: Number of strings to skip over at beginning of list. + * + * Don't call this function directly. It is a utility helper for the + * of_property_read_string*() family of functions. + */ +int of_property_read_string_helper(const struct device_node *np, + const char *propname, const char **out_strs, + size_t sz, int skip) +{ + const struct property *prop = of_find_property(np, propname, NULL); + int l = 0, i = 0; + const char *p, *end; + + if (!prop) + return -EINVAL; + if (!prop->value) + return -ENODATA; + p = prop->value; + end = p + prop->length; + + for (i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l) { + l = strnlen(p, end - p) + 1; + if (p + l > end) + return -EILSEQ; + if (out_strs && i >= skip) + *out_strs++ = p; + } + i -= skip; + return i <= 0 ? -ENODATA : i; +} +EXPORT_SYMBOL_GPL(of_property_read_string_helper); + +const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur, + u32 *pu) +{ + const void *curv = cur; + + if (!prop) + return NULL; + + if (!cur) { + curv = prop->value; + goto out_val; + } + + curv += sizeof(*cur); + if (curv >= prop->value + prop->length) + return NULL; + +out_val: + *pu = be32_to_cpup(curv); + return curv; +} +EXPORT_SYMBOL_GPL(of_prop_next_u32); + +const char *of_prop_next_string(struct property *prop, const char *cur) +{ + const void *curv = cur; + + if (!prop) + return NULL; + + if (!cur) + return prop->value; + + curv += strlen(cur) + 1; + if (curv >= prop->value + prop->length) + return NULL; + + return curv; +} +EXPORT_SYMBOL_GPL(of_prop_next_string); + +/** + * of_graph_parse_endpoint() - parse common endpoint node properties + * @node: pointer to endpoint device_node + * @endpoint: pointer to the OF endpoint data structure + * + * The caller should hold a reference to @node. + */ +int of_graph_parse_endpoint(const struct device_node *node, + struct of_endpoint *endpoint) +{ + struct device_node *port_node = of_get_parent(node); + + WARN_ONCE(!port_node, "%s(): endpoint %pOF has no parent node\n", + __func__, node); + + memset(endpoint, 0, sizeof(*endpoint)); + + endpoint->local_node = node; + /* + * It doesn't matter whether the two calls below succeed. + * If they don't then the default value 0 is used. + */ + of_property_read_u32(port_node, "reg", &endpoint->port); + of_property_read_u32(node, "reg", &endpoint->id); + + of_node_put(port_node); + + return 0; +} +EXPORT_SYMBOL(of_graph_parse_endpoint); + +/** + * of_graph_get_port_by_id() - get the port matching a given id + * @parent: pointer to the parent device node + * @id: id of the port + * + * Return: A 'port' node pointer with refcount incremented. The caller + * has to use of_node_put() on it when done. + */ +struct device_node *of_graph_get_port_by_id(struct device_node *parent, u32 id) +{ + struct device_node *node, *port; + + node = of_get_child_by_name(parent, "ports"); + if (node) + parent = node; + + for_each_child_of_node(parent, port) { + u32 port_id = 0; + + if (!of_node_name_eq(port, "port")) + continue; + of_property_read_u32(port, "reg", &port_id); + if (id == port_id) + break; + } + + of_node_put(node); + + return port; +} +EXPORT_SYMBOL(of_graph_get_port_by_id); + +/** + * of_graph_get_next_endpoint() - get next endpoint node + * @parent: pointer to the parent device node + * @prev: previous endpoint node, or NULL to get first + * + * Return: An 'endpoint' node pointer with refcount incremented. Refcount + * of the passed @prev node is decremented. + */ +struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, + struct device_node *prev) +{ + struct device_node *endpoint; + struct device_node *port; + + if (!parent) + return NULL; + + /* + * Start by locating the port node. If no previous endpoint is specified + * search for the first port node, otherwise get the previous endpoint + * parent port node. + */ + if (!prev) { + struct device_node *node; + + node = of_get_child_by_name(parent, "ports"); + if (node) + parent = node; + + port = of_get_child_by_name(parent, "port"); + of_node_put(node); + + if (!port) { + pr_err("graph: no port node found in %pOF\n", parent); + return NULL; + } + } else { + port = of_get_parent(prev); + if (WARN_ONCE(!port, "%s(): endpoint %pOF has no parent node\n", + __func__, prev)) + return NULL; + } + + while (1) { + /* + * Now that we have a port node, get the next endpoint by + * getting the next child. If the previous endpoint is NULL this + * will return the first child. + */ + endpoint = of_get_next_child(port, prev); + if (endpoint) { + of_node_put(port); + return endpoint; + } + + /* No more endpoints under this port, try the next one. */ + prev = NULL; + + do { + port = of_get_next_child(parent, port); + if (!port) + return NULL; + } while (!of_node_name_eq(port, "port")); + } +} +EXPORT_SYMBOL(of_graph_get_next_endpoint); + +/** + * of_graph_get_endpoint_by_regs() - get endpoint node of specific identifiers + * @parent: pointer to the parent device node + * @port_reg: identifier (value of reg property) of the parent port node + * @reg: identifier (value of reg property) of the endpoint node + * + * Return: An 'endpoint' node pointer which is identified by reg and at the same + * is the child of a port node identified by port_reg. reg and port_reg are + * ignored when they are -1. Use of_node_put() on the pointer when done. + */ +struct device_node *of_graph_get_endpoint_by_regs( + const struct device_node *parent, int port_reg, int reg) +{ + struct of_endpoint endpoint; + struct device_node *node = NULL; + + for_each_endpoint_of_node(parent, node) { + of_graph_parse_endpoint(node, &endpoint); + if (((port_reg == -1) || (endpoint.port == port_reg)) && + ((reg == -1) || (endpoint.id == reg))) + return node; + } + + return NULL; +} +EXPORT_SYMBOL(of_graph_get_endpoint_by_regs); + +/** + * of_graph_get_remote_endpoint() - get remote endpoint node + * @node: pointer to a local endpoint device_node + * + * Return: Remote endpoint node associated with remote endpoint node linked + * to @node. Use of_node_put() on it when done. + */ +struct device_node *of_graph_get_remote_endpoint(const struct device_node *node) +{ + /* Get remote endpoint node. */ + return of_parse_phandle(node, "remote-endpoint", 0); +} +EXPORT_SYMBOL(of_graph_get_remote_endpoint); + +/** + * of_graph_get_port_parent() - get port's parent node + * @node: pointer to a local endpoint device_node + * + * Return: device node associated with endpoint node linked + * to @node. Use of_node_put() on it when done. + */ +struct device_node *of_graph_get_port_parent(struct device_node *node) +{ + unsigned int depth; + + if (!node) + return NULL; + + /* + * Preserve usecount for passed in node as of_get_next_parent() + * will do of_node_put() on it. + */ + of_node_get(node); + + /* Walk 3 levels up only if there is 'ports' node. */ + for (depth = 3; depth && node; depth--) { + node = of_get_next_parent(node); + if (depth == 2 && !of_node_name_eq(node, "ports")) + break; + } + return node; +} +EXPORT_SYMBOL(of_graph_get_port_parent); + +/** + * of_graph_get_remote_port_parent() - get remote port's parent node + * @node: pointer to a local endpoint device_node + * + * Return: Remote device node associated with remote endpoint node linked + * to @node. Use of_node_put() on it when done. + */ +struct device_node *of_graph_get_remote_port_parent( + const struct device_node *node) +{ + struct device_node *np, *pp; + + /* Get remote endpoint node. */ + np = of_graph_get_remote_endpoint(node); + + pp = of_graph_get_port_parent(np); + + of_node_put(np); + + return pp; +} +EXPORT_SYMBOL(of_graph_get_remote_port_parent); + +/** + * of_graph_get_remote_port() - get remote port node + * @node: pointer to a local endpoint device_node + * + * Return: Remote port node associated with remote endpoint node linked + * to @node. Use of_node_put() on it when done. + */ +struct device_node *of_graph_get_remote_port(const struct device_node *node) +{ + struct device_node *np; + + /* Get remote endpoint node. */ + np = of_graph_get_remote_endpoint(node); + if (!np) + return NULL; + return of_get_next_parent(np); +} +EXPORT_SYMBOL(of_graph_get_remote_port); + +int of_graph_get_endpoint_count(const struct device_node *np) +{ + struct device_node *endpoint; + int num = 0; + + for_each_endpoint_of_node(np, endpoint) + num++; + + return num; +} +EXPORT_SYMBOL(of_graph_get_endpoint_count); + +/** + * of_graph_get_remote_node() - get remote parent device_node for given port/endpoint + * @node: pointer to parent device_node containing graph port/endpoint + * @port: identifier (value of reg property) of the parent port node + * @endpoint: identifier (value of reg property) of the endpoint node + * + * Return: Remote device node associated with remote endpoint node linked + * to @node. Use of_node_put() on it when done. + */ +struct device_node *of_graph_get_remote_node(const struct device_node *node, + u32 port, u32 endpoint) +{ + struct device_node *endpoint_node, *remote; + + endpoint_node = of_graph_get_endpoint_by_regs(node, port, endpoint); + if (!endpoint_node) { + pr_debug("no valid endpoint (%d, %d) for node %pOF\n", + port, endpoint, node); + return NULL; + } + + remote = of_graph_get_remote_port_parent(endpoint_node); + of_node_put(endpoint_node); + if (!remote) { + pr_debug("no valid remote node\n"); + return NULL; + } + + if (!of_device_is_available(remote)) { + pr_debug("not available for remote node\n"); + of_node_put(remote); + return NULL; + } + + return remote; +} +EXPORT_SYMBOL(of_graph_get_remote_node); + +static struct fwnode_handle *of_fwnode_get(struct fwnode_handle *fwnode) +{ + return of_fwnode_handle(of_node_get(to_of_node(fwnode))); +} + +static void of_fwnode_put(struct fwnode_handle *fwnode) +{ + of_node_put(to_of_node(fwnode)); +} + +static bool of_fwnode_device_is_available(const struct fwnode_handle *fwnode) +{ + return of_device_is_available(to_of_node(fwnode)); +} + +static bool of_fwnode_property_present(const struct fwnode_handle *fwnode, + const char *propname) +{ + return of_property_read_bool(to_of_node(fwnode), propname); +} + +static int of_fwnode_property_read_int_array(const struct fwnode_handle *fwnode, + const char *propname, + unsigned int elem_size, void *val, + size_t nval) +{ + const struct device_node *node = to_of_node(fwnode); + + if (!val) + return of_property_count_elems_of_size(node, propname, + elem_size); + + switch (elem_size) { + case sizeof(u8): + return of_property_read_u8_array(node, propname, val, nval); + case sizeof(u16): + return of_property_read_u16_array(node, propname, val, nval); + case sizeof(u32): + return of_property_read_u32_array(node, propname, val, nval); + case sizeof(u64): + return of_property_read_u64_array(node, propname, val, nval); + } + + return -ENXIO; +} + +static int +of_fwnode_property_read_string_array(const struct fwnode_handle *fwnode, + const char *propname, const char **val, + size_t nval) +{ + const struct device_node *node = to_of_node(fwnode); + + return val ? + of_property_read_string_array(node, propname, val, nval) : + of_property_count_strings(node, propname); +} + +static const char *of_fwnode_get_name(const struct fwnode_handle *fwnode) +{ + return kbasename(to_of_node(fwnode)->full_name); +} + +static const char *of_fwnode_get_name_prefix(const struct fwnode_handle *fwnode) +{ + /* Root needs no prefix here (its name is "/"). */ + if (!to_of_node(fwnode)->parent) + return ""; + + return "/"; +} + +static struct fwnode_handle * +of_fwnode_get_parent(const struct fwnode_handle *fwnode) +{ + return of_fwnode_handle(of_get_parent(to_of_node(fwnode))); +} + +static struct fwnode_handle * +of_fwnode_get_next_child_node(const struct fwnode_handle *fwnode, + struct fwnode_handle *child) +{ + return of_fwnode_handle(of_get_next_available_child(to_of_node(fwnode), + to_of_node(child))); +} + +static struct fwnode_handle * +of_fwnode_get_named_child_node(const struct fwnode_handle *fwnode, + const char *childname) +{ + const struct device_node *node = to_of_node(fwnode); + struct device_node *child; + + for_each_available_child_of_node(node, child) + if (of_node_name_eq(child, childname)) + return of_fwnode_handle(child); + + return NULL; +} + +static int +of_fwnode_get_reference_args(const struct fwnode_handle *fwnode, + const char *prop, const char *nargs_prop, + unsigned int nargs, unsigned int index, + struct fwnode_reference_args *args) +{ + struct of_phandle_args of_args; + unsigned int i; + int ret; + + if (nargs_prop) + ret = of_parse_phandle_with_args(to_of_node(fwnode), prop, + nargs_prop, index, &of_args); + else + ret = of_parse_phandle_with_fixed_args(to_of_node(fwnode), prop, + nargs, index, &of_args); + if (ret < 0) + return ret; + if (!args) { + of_node_put(of_args.np); + return 0; + } + + args->nargs = of_args.args_count; + args->fwnode = of_fwnode_handle(of_args.np); + + for (i = 0; i < NR_FWNODE_REFERENCE_ARGS; i++) + args->args[i] = i < of_args.args_count ? of_args.args[i] : 0; + + return 0; +} + +static struct fwnode_handle * +of_fwnode_graph_get_next_endpoint(const struct fwnode_handle *fwnode, + struct fwnode_handle *prev) +{ + return of_fwnode_handle(of_graph_get_next_endpoint(to_of_node(fwnode), + to_of_node(prev))); +} + +static struct fwnode_handle * +of_fwnode_graph_get_remote_endpoint(const struct fwnode_handle *fwnode) +{ + return of_fwnode_handle( + of_graph_get_remote_endpoint(to_of_node(fwnode))); +} + +static struct fwnode_handle * +of_fwnode_graph_get_port_parent(struct fwnode_handle *fwnode) +{ + struct device_node *np; + + /* Get the parent of the port */ + np = of_get_parent(to_of_node(fwnode)); + if (!np) + return NULL; + + /* Is this the "ports" node? If not, it's the port parent. */ + if (!of_node_name_eq(np, "ports")) + return of_fwnode_handle(np); + + return of_fwnode_handle(of_get_next_parent(np)); +} + +static int of_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode, + struct fwnode_endpoint *endpoint) +{ + const struct device_node *node = to_of_node(fwnode); + struct device_node *port_node = of_get_parent(node); + + endpoint->local_fwnode = fwnode; + + of_property_read_u32(port_node, "reg", &endpoint->port); + of_property_read_u32(node, "reg", &endpoint->id); + + of_node_put(port_node); + + return 0; +} + +static const void * +of_fwnode_device_get_match_data(const struct fwnode_handle *fwnode, + const struct device *dev) +{ + return of_device_get_match_data(dev); +} + +static bool of_is_ancestor_of(struct device_node *test_ancestor, + struct device_node *child) +{ + of_node_get(child); + while (child) { + if (child == test_ancestor) { + of_node_put(child); + return true; + } + child = of_get_next_parent(child); + } + return false; +} + +/** + * of_get_next_parent_dev - Add device link to supplier from supplier phandle + * @np: device tree node + * + * Given a device tree node (@np), this function finds its closest ancestor + * device tree node that has a corresponding struct device. + * + * The caller of this function is expected to call put_device() on the returned + * device when they are done. + */ +static struct device *of_get_next_parent_dev(struct device_node *np) +{ + struct device *dev = NULL; + + of_node_get(np); + do { + np = of_get_next_parent(np); + if (np) + dev = get_dev_from_fwnode(&np->fwnode); + } while (np && !dev); + of_node_put(np); + return dev; +} + +/** + * of_link_to_phandle - Add device link to supplier from supplier phandle + * @dev: consumer device + * @sup_np: phandle to supplier device tree node + * + * Given a phandle to a supplier device tree node (@sup_np), this function + * finds the device that owns the supplier device tree node and creates a + * device link from @dev consumer device to the supplier device. This function + * doesn't create device links for invalid scenarios such as trying to create a + * link with a parent device as the consumer of its child device. In such + * cases, it returns an error. + * + * Returns: + * - 0 if link successfully created to supplier + * - -EAGAIN if linking to the supplier should be reattempted + * - -EINVAL if the supplier link is invalid and should not be created + * - -ENODEV if there is no device that corresponds to the supplier phandle + */ +static int of_link_to_phandle(struct device *dev, struct device_node *sup_np, + u32 dl_flags) +{ + struct device *sup_dev, *sup_par_dev; + int ret = 0; + struct device_node *tmp_np = sup_np; + + of_node_get(sup_np); + /* + * Find the device node that contains the supplier phandle. It may be + * @sup_np or it may be an ancestor of @sup_np. + */ + while (sup_np) { + + /* Don't allow linking to a disabled supplier */ + if (!of_device_is_available(sup_np)) { + of_node_put(sup_np); + sup_np = NULL; + } + + if (of_find_property(sup_np, "compatible", NULL)) + break; + + sup_np = of_get_next_parent(sup_np); + } + + if (!sup_np) { + dev_dbg(dev, "Not linking to %pOFP - No device\n", tmp_np); + return -ENODEV; + } + + /* + * Don't allow linking a device node as a consumer of one of its + * descendant nodes. By definition, a child node can't be a functional + * dependency for the parent node. + */ + if (of_is_ancestor_of(dev->of_node, sup_np)) { + dev_dbg(dev, "Not linking to %pOFP - is descendant\n", sup_np); + of_node_put(sup_np); + return -EINVAL; + } + sup_dev = get_dev_from_fwnode(&sup_np->fwnode); + if (!sup_dev && of_node_check_flag(sup_np, OF_POPULATED)) { + /* Early device without struct device. */ + dev_dbg(dev, "Not linking to %pOFP - No struct device\n", + sup_np); + of_node_put(sup_np); + return -ENODEV; + } else if (!sup_dev) { + /* + * DL_FLAG_SYNC_STATE_ONLY doesn't block probing and supports + * cycles. So cycle detection isn't necessary and shouldn't be + * done. + */ + if (dl_flags & DL_FLAG_SYNC_STATE_ONLY) { + of_node_put(sup_np); + return -EAGAIN; + } + + sup_par_dev = of_get_next_parent_dev(sup_np); + + if (sup_par_dev && device_is_dependent(dev, sup_par_dev)) { + /* Cyclic dependency detected, don't try to link */ + dev_dbg(dev, "Not linking to %pOFP - cycle detected\n", + sup_np); + ret = -EINVAL; + } else { + /* + * Can't check for cycles or no cycles. So let's try + * again later. + */ + ret = -EAGAIN; + } + + of_node_put(sup_np); + put_device(sup_par_dev); + return ret; + } + of_node_put(sup_np); + if (!device_link_add(dev, sup_dev, dl_flags)) + ret = -EINVAL; + put_device(sup_dev); + return ret; +} + +/** + * parse_prop_cells - Property parsing function for suppliers + * + * @np: Pointer to device tree node containing a list + * @prop_name: Name of property to be parsed. Expected to hold phandle values + * @index: For properties holding a list of phandles, this is the index + * into the list. + * @list_name: Property name that is known to contain list of phandle(s) to + * supplier(s) + * @cells_name: property name that specifies phandles' arguments count + * + * This is a helper function to parse properties that have a known fixed name + * and are a list of phandles and phandle arguments. + * + * Returns: + * - phandle node pointer with refcount incremented. Caller must of_node_put() + * on it when done. + * - NULL if no phandle found at index + */ +static struct device_node *parse_prop_cells(struct device_node *np, + const char *prop_name, int index, + const char *list_name, + const char *cells_name) +{ + struct of_phandle_args sup_args; + + if (strcmp(prop_name, list_name)) + return NULL; + + if (of_parse_phandle_with_args(np, list_name, cells_name, index, + &sup_args)) + return NULL; + + return sup_args.np; +} + +#define DEFINE_SIMPLE_PROP(fname, name, cells) \ +static struct device_node *parse_##fname(struct device_node *np, \ + const char *prop_name, int index) \ +{ \ + return parse_prop_cells(np, prop_name, index, name, cells); \ +} + +static int strcmp_suffix(const char *str, const char *suffix) +{ + unsigned int len, suffix_len; + + len = strlen(str); + suffix_len = strlen(suffix); + if (len <= suffix_len) + return -1; + return strcmp(str + len - suffix_len, suffix); +} + +/** + * parse_suffix_prop_cells - Suffix property parsing function for suppliers + * + * @np: Pointer to device tree node containing a list + * @prop_name: Name of property to be parsed. Expected to hold phandle values + * @index: For properties holding a list of phandles, this is the index + * into the list. + * @suffix: Property suffix that is known to contain list of phandle(s) to + * supplier(s) + * @cells_name: property name that specifies phandles' arguments count + * + * This is a helper function to parse properties that have a known fixed suffix + * and are a list of phandles and phandle arguments. + * + * Returns: + * - phandle node pointer with refcount incremented. Caller must of_node_put() + * on it when done. + * - NULL if no phandle found at index + */ +static struct device_node *parse_suffix_prop_cells(struct device_node *np, + const char *prop_name, int index, + const char *suffix, + const char *cells_name) +{ + struct of_phandle_args sup_args; + + if (strcmp_suffix(prop_name, suffix)) + return NULL; + + if (of_parse_phandle_with_args(np, prop_name, cells_name, index, + &sup_args)) + return NULL; + + return sup_args.np; +} + +#define DEFINE_SUFFIX_PROP(fname, suffix, cells) \ +static struct device_node *parse_##fname(struct device_node *np, \ + const char *prop_name, int index) \ +{ \ + return parse_suffix_prop_cells(np, prop_name, index, suffix, cells); \ +} + +/** + * struct supplier_bindings - Property parsing functions for suppliers + * + * @parse_prop: function name + * parse_prop() finds the node corresponding to a supplier phandle + * @parse_prop.np: Pointer to device node holding supplier phandle property + * @parse_prop.prop_name: Name of property holding a phandle value + * @parse_prop.index: For properties holding a list of phandles, this is the + * index into the list + * + * Returns: + * parse_prop() return values are + * - phandle node pointer with refcount incremented. Caller must of_node_put() + * on it when done. + * - NULL if no phandle found at index + */ +struct supplier_bindings { + struct device_node *(*parse_prop)(struct device_node *np, + const char *prop_name, int index); +}; + +DEFINE_SIMPLE_PROP(clocks, "clocks", "#clock-cells") +DEFINE_SIMPLE_PROP(interconnects, "interconnects", "#interconnect-cells") +DEFINE_SIMPLE_PROP(iommus, "iommus", "#iommu-cells") +DEFINE_SIMPLE_PROP(mboxes, "mboxes", "#mbox-cells") +DEFINE_SIMPLE_PROP(io_channels, "io-channel", "#io-channel-cells") +DEFINE_SIMPLE_PROP(interrupt_parent, "interrupt-parent", NULL) +DEFINE_SIMPLE_PROP(dmas, "dmas", "#dma-cells") +DEFINE_SIMPLE_PROP(power_domains, "power-domains", "#power-domain-cells") +DEFINE_SIMPLE_PROP(hwlocks, "hwlocks", "#hwlock-cells") +DEFINE_SIMPLE_PROP(extcon, "extcon", NULL) +DEFINE_SIMPLE_PROP(interrupts_extended, "interrupts-extended", + "#interrupt-cells") +DEFINE_SIMPLE_PROP(nvmem_cells, "nvmem-cells", NULL) +DEFINE_SIMPLE_PROP(phys, "phys", "#phy-cells") +DEFINE_SIMPLE_PROP(wakeup_parent, "wakeup-parent", NULL) +DEFINE_SIMPLE_PROP(pinctrl0, "pinctrl-0", NULL) +DEFINE_SIMPLE_PROP(pinctrl1, "pinctrl-1", NULL) +DEFINE_SIMPLE_PROP(pinctrl2, "pinctrl-2", NULL) +DEFINE_SIMPLE_PROP(pinctrl3, "pinctrl-3", NULL) +DEFINE_SIMPLE_PROP(pinctrl4, "pinctrl-4", NULL) +DEFINE_SIMPLE_PROP(pinctrl5, "pinctrl-5", NULL) +DEFINE_SIMPLE_PROP(pinctrl6, "pinctrl-6", NULL) +DEFINE_SIMPLE_PROP(pinctrl7, "pinctrl-7", NULL) +DEFINE_SIMPLE_PROP(pinctrl8, "pinctrl-8", NULL) +DEFINE_SUFFIX_PROP(regulators, "-supply", NULL) +DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells") + +static struct device_node *parse_gpios(struct device_node *np, + const char *prop_name, int index) +{ + if (!strcmp_suffix(prop_name, ",nr-gpios")) + return NULL; + + return parse_suffix_prop_cells(np, prop_name, index, "-gpios", + "#gpio-cells"); +} + +static struct device_node *parse_iommu_maps(struct device_node *np, + const char *prop_name, int index) +{ + if (strcmp(prop_name, "iommu-map")) + return NULL; + + return of_parse_phandle(np, prop_name, (index * 4) + 1); +} + +static const struct supplier_bindings of_supplier_bindings[] = { + { .parse_prop = parse_clocks, }, + { .parse_prop = parse_interconnects, }, + { .parse_prop = parse_iommus, }, + { .parse_prop = parse_iommu_maps, }, + { .parse_prop = parse_mboxes, }, + { .parse_prop = parse_io_channels, }, + { .parse_prop = parse_interrupt_parent, }, + { .parse_prop = parse_dmas, }, + { .parse_prop = parse_power_domains, }, + { .parse_prop = parse_hwlocks, }, + { .parse_prop = parse_extcon, }, + { .parse_prop = parse_interrupts_extended, }, + { .parse_prop = parse_nvmem_cells, }, + { .parse_prop = parse_phys, }, + { .parse_prop = parse_wakeup_parent, }, + { .parse_prop = parse_pinctrl0, }, + { .parse_prop = parse_pinctrl1, }, + { .parse_prop = parse_pinctrl2, }, + { .parse_prop = parse_pinctrl3, }, + { .parse_prop = parse_pinctrl4, }, + { .parse_prop = parse_pinctrl5, }, + { .parse_prop = parse_pinctrl6, }, + { .parse_prop = parse_pinctrl7, }, + { .parse_prop = parse_pinctrl8, }, + { .parse_prop = parse_regulators, }, + { .parse_prop = parse_gpio, }, + { .parse_prop = parse_gpios, }, + {} +}; + +/** + * of_link_property - Create device links to suppliers listed in a property + * @dev: Consumer device + * @con_np: The consumer device tree node which contains the property + * @prop_name: Name of property to be parsed + * + * This function checks if the property @prop_name that is present in the + * @con_np device tree node is one of the known common device tree bindings + * that list phandles to suppliers. If @prop_name isn't one, this function + * doesn't do anything. + * + * If @prop_name is one, this function attempts to create device links from the + * consumer device @dev to all the devices of the suppliers listed in + * @prop_name. + * + * Any failed attempt to create a device link will NOT result in an immediate + * return. of_link_property() must create links to all the available supplier + * devices even when attempts to create a link to one or more suppliers fail. + */ +static int of_link_property(struct device *dev, struct device_node *con_np, + const char *prop_name) +{ + struct device_node *phandle; + const struct supplier_bindings *s = of_supplier_bindings; + unsigned int i = 0; + bool matched = false; + int ret = 0; + u32 dl_flags; + + if (dev->of_node == con_np) + dl_flags = fw_devlink_get_flags(); + else + dl_flags = DL_FLAG_SYNC_STATE_ONLY; + + /* Do not stop at first failed link, link all available suppliers. */ + while (!matched && s->parse_prop) { + while ((phandle = s->parse_prop(con_np, prop_name, i))) { + matched = true; + i++; + if (of_link_to_phandle(dev, phandle, dl_flags) + == -EAGAIN) + ret = -EAGAIN; + of_node_put(phandle); + } + s++; + } + return ret; +} + +static int of_link_to_suppliers(struct device *dev, + struct device_node *con_np) +{ + struct device_node *child; + struct property *p; + int ret = 0; + + for_each_property_of_node(con_np, p) + if (of_link_property(dev, con_np, p->name)) + ret = -ENODEV; + + for_each_available_child_of_node(con_np, child) + if (of_link_to_suppliers(dev, child) && !ret) + ret = -EAGAIN; + + return ret; +} + +static int of_fwnode_add_links(const struct fwnode_handle *fwnode, + struct device *dev) +{ + if (unlikely(!is_of_node(fwnode))) + return 0; + + return of_link_to_suppliers(dev, to_of_node(fwnode)); +} + +const struct fwnode_operations of_fwnode_ops = { + .get = of_fwnode_get, + .put = of_fwnode_put, + .device_is_available = of_fwnode_device_is_available, + .device_get_match_data = of_fwnode_device_get_match_data, + .property_present = of_fwnode_property_present, + .property_read_int_array = of_fwnode_property_read_int_array, + .property_read_string_array = of_fwnode_property_read_string_array, + .get_name = of_fwnode_get_name, + .get_name_prefix = of_fwnode_get_name_prefix, + .get_parent = of_fwnode_get_parent, + .get_next_child_node = of_fwnode_get_next_child_node, + .get_named_child_node = of_fwnode_get_named_child_node, + .get_reference_args = of_fwnode_get_reference_args, + .graph_get_next_endpoint = of_fwnode_graph_get_next_endpoint, + .graph_get_remote_endpoint = of_fwnode_graph_get_remote_endpoint, + .graph_get_port_parent = of_fwnode_graph_get_port_parent, + .graph_parse_endpoint = of_fwnode_graph_parse_endpoint, + .add_links = of_fwnode_add_links, +}; +EXPORT_SYMBOL_GPL(of_fwnode_ops); |