of/flattree: Add of_flat_dt_match() helper function
This patch adds of_flat_dt_match() which tests a node for
compatibility with a list of values and converts the relevant powerpc
platform code to use it. This approach simplifies the board support
code a bit.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 8a90ee4..c787c3d 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -78,19 +78,23 @@
* @blob: A device tree blob
* @node: node to test
* @compat: compatible string to compare with compatible list.
+ *
+ * On match, returns a non-zero value with smaller values returned for more
+ * specific compatible values.
*/
int of_fdt_is_compatible(struct boot_param_header *blob,
unsigned long node, const char *compat)
{
const char *cp;
- unsigned long cplen, l;
+ unsigned long cplen, l, score = 0;
cp = of_fdt_get_property(blob, node, "compatible", &cplen);
if (cp == NULL)
return 0;
while (cplen > 0) {
+ score++;
if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
- return 1;
+ return score;
l = strlen(cp) + 1;
cp += l;
cplen -= l;
@@ -99,6 +103,27 @@
return 0;
}
+/**
+ * of_fdt_match - Return true if node matches a list of compatible values
+ */
+int of_fdt_match(struct boot_param_header *blob, unsigned long node,
+ const char **compat)
+{
+ unsigned int tmp, score = 0;
+
+ if (!compat)
+ return 0;
+
+ while (*compat) {
+ tmp = of_fdt_is_compatible(blob, node, *compat);
+ if (tmp && (score == 0 || (tmp < score)))
+ score = tmp;
+ compat++;
+ }
+
+ return score;
+}
+
static void *unflatten_dt_alloc(unsigned long *mem, unsigned long size,
unsigned long align)
{
@@ -511,6 +536,14 @@
return of_fdt_is_compatible(initial_boot_params, node, compat);
}
+/**
+ * of_flat_dt_match - Return true if node matches a list of compatible values
+ */
+int __init of_flat_dt_match(unsigned long node, const char **compat)
+{
+ return of_fdt_match(initial_boot_params, node, compat);
+}
+
#ifdef CONFIG_BLK_DEV_INITRD
/**
* early_init_dt_check_for_initrd - Decode initrd location from flat tree