From: Stephen Warren <swarren@xxxxxxxxxx>
The simplest case of __of_parse_phandle_with_args() now implements the
semantics of of_parse_phandle(). Rewrite of_parse_phandle() to call
__of_parse_phandle_with_args() rather than open-coding the simple case.
Optimize __of_parse_phandle_with_args() so that it doesn't call
of_find_node_by_phandle() except when it's strictly needed. This avoids
introducing too much overhead when replacing of_parse_phandle().
Signed-off-by: Stephen Warren <swarren@xxxxxxxxxx>
Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
---
v6: Fixed commit description to match code change. Enhance
__of_parse_phandle_with_args() to avoid calling
of_find_node_by_phandle() except when needed.
v5: New patch.
---
drivers/of/base.c | 31 ++++++++++++++++++++-----------
1 file changed, 20 insertions(+), 11 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 3a5cd9e..c8be59d 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1112,13 +1112,20 @@ static int __of_parse_phandle_with_args(const struct device_node *np,
if (phandle) {
/*
* Find the provider node and parse the #*-cells
- * property to determine the argument length
+ * property to determine the argument length.
+ *
+ * This is not needed if the cell count is hard-coded
+ * (i.e. cells_name not set, but cell_count is set),
+ * except when we're going to return the found node
+ * below.
*/
- node = of_find_node_by_phandle(phandle);
- if (!node) {
- pr_err("%s: could not find phandle\n",
- np->full_name);
- goto err;
+ if (cells_name || cur_index == index) {
+ node = of_find_node_by_phandle(phandle);
+ if (!node) {
+ pr_err("%s: could not find phandle\n",
+ np->full_name);
+ goto err;
+ }
}
if (cells_name) {
@@ -1203,14 +1210,16 @@ static int __of_parse_phandle_with_args(const struct device_node *np,
struct device_node *of_parse_phandle(const struct device_node *np,
const char *phandle_name, int index)
{
- const __be32 *phandle;
- int size;
+ struct of_phandle_args args;
+
+ if (index < 0)
+ return NULL;
- phandle = of_get_property(np, phandle_name, &size);
- if ((!phandle) || (size < sizeof(*phandle) * (index + 1)))
+ if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0,
+ index, &args))
return NULL;
- return of_find_node_by_phandle(be32_to_cpup(phandle + index));
+ return args.np;
}
EXPORT_SYMBOL(of_parse_phandle);
--
1.8.1.5
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