}
EXPORT_SYMBOL(of_get_cpu_node);
-/** Checks if the given "compat" string matches one of the strings in
- * the device's "compatible" property
+/**
+ * __of_device_is_compatible() - Check if the node matches given constraints
+ * @device: pointer to node
+ * @compat: required compatible string, NULL or "" for any match
+ * @type: required device_type value, NULL or "" for any match
+ * @name: required node name, NULL or "" for any match
+ *
+ * Checks if the given @compat, @type and @name strings match the
+ * properties of the given @device. A constraints can be skipped by
+ * passing NULL or an empty string as the constraint.
+ *
+ * Returns 0 for no match, and a positive integer on match. The return
+ * value is a relative score with larger values indicating better
+ * matches. The score is weighted for the most specific compatible value
+ * to get the highest score. Matching type is next, followed by matching
+ * name. Practically speaking, this results in the following priority
+ * order for matches:
+ *
+ * 1. specific compatible && type && name
+ * 2. specific compatible && type
+ * 3. specific compatible && name
+ * 4. specific compatible
+ * 5. general compatible && type && name
+ * 6. general compatible && type
+ * 7. general compatible && name
+ * 8. general compatible
+ * 9. type && name
+ * 10. type
+ * 11. name
*/
static int __of_device_is_compatible(const struct device_node *device,
- const char *compat)
+ const char *compat, const char *type, const char *name)
{
- const char* cp;
- int cplen, l;
+ struct property *prop;
+ const char *cp;
+ int index = 0, score = 0;
+
+ /* Compatible match has highest priority */
+ if (compat && compat[0]) {
+ prop = __of_find_property(device, "compatible", NULL);
+ for (cp = of_prop_next_string(prop, NULL); cp;
+ cp = of_prop_next_string(prop, cp), index++) {
+ if (of_compat_cmp(cp, compat, strlen(compat)) == 0) {
+ score = INT_MAX/2 - (index << 2);
+ break;
+ }
+ }
+ if (!score)
+ return 0;
+ }
- cp = __of_get_property(device, "compatible", &cplen);
- if (cp == NULL)
- return 0;
- while (cplen > 0) {
- if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
- return 1;
- l = strlen(cp) + 1;
- cp += l;
- cplen -= l;
+ /* Matching type is better than matching name */
+ if (type && type[0]) {
+ if (!device->type || of_node_cmp(type, device->type))
+ return 0;
+ score += 2;
}
- return 0;
+ /* Matching name is a bit better than not */
+ if (name && name[0]) {
+ if (!device->name || of_node_cmp(name, device->name))
+ return 0;
+ score++;
+ }
+
+ return score;
}
/** Checks if the given "compat" string matches one of the strings in
int res;
raw_spin_lock_irqsave(&devtree_lock, flags);
- res = __of_device_is_compatible(device, compat);
+ res = __of_device_is_compatible(device, compat, NULL, NULL);
raw_spin_unlock_irqrestore(&devtree_lock, flags);
return res;
}
raw_spin_lock_irqsave(&devtree_lock, flags);
np = from ? from->allnext : of_allnodes;
for (; np; np = np->allnext) {
- if (type
- && !(np->type && (of_node_cmp(np->type, type) == 0)))
- continue;
- if (__of_device_is_compatible(np, compatible) &&
+ if (__of_device_is_compatible(np, compatible, type, NULL) &&
of_node_get(np))
break;
}
const struct of_device_id *__of_match_node(const struct of_device_id *matches,
const struct device_node *node)
{
- const char *cp;
- int cplen, l;
+ const struct of_device_id *best_match = NULL;
+ int score, best_score = 0;
if (!matches)
return NULL;
- cp = __of_get_property(node, "compatible", &cplen);
- do {
- const struct of_device_id *m = matches;
-
- /* Check against matches with current compatible string */
- while (m->name[0] || m->type[0] || m->compatible[0]) {
- int match = 1;
- if (m->name[0])
- match &= node->name
- && !strcmp(m->name, node->name);
- if (m->type[0])
- match &= node->type
- && !strcmp(m->type, node->type);
- if (m->compatible[0])
- match &= cp
- && !of_compat_cmp(m->compatible, cp,
- strlen(m->compatible));
- if (match)
- return m;
- m++;
- }
-
- /* Get node's next compatible string */
- if (cp) {
- l = strlen(cp) + 1;
- cp += l;
- cplen -= l;
+ for (; matches->name[0] || matches->type[0] || matches->compatible[0]; matches++) {
+ score = __of_device_is_compatible(node, matches->compatible,
+ matches->type, matches->name);
+ if (score > best_score) {
+ best_match = matches;
+ best_score = score;
}
- } while (cp && (cplen > 0));
+ }
- return NULL;
+ return best_match;
}
/**
* @matches: array of of device match structures to search in
* @node: the of device structure to match against
*
- * Low level utility function used by device matching. Matching order
- * is to compare each of the node's compatibles with all given matches
- * first. This implies node's compatible is sorted from specific to
- * generic while matches can be in any order.
+ * Low level utility function used by device matching.
*/
const struct of_device_id *of_match_node(const struct of_device_id *matches,
const struct device_node *node)
}
EXPORT_SYMBOL(of_find_node_by_phandle);
+/**
+ * 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. Returns 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 %s is not a multiple of %d\n",
+ propname, np->full_name, elem_size);
+ return -EINVAL;
+ }
+
+ return prop->length / elem_size;
+}
+EXPORT_SYMBOL_GPL(of_property_count_elems_of_size);
+
/**
* of_find_property_value_of_size
*
projects / cascardo / linux.git / blobdiff