ARM: shmobile: Fix device node reference leakage in shmobile_init_delay

The of_find_compatible_node() function returns a new reference to the
found node. Instead of just adding of_node_put() calls, simplify the
code by moving the CPU identification logic inside the loop over cpu
nodes, in order to lower complexity from O(n) to O(1) by replacing
of_find_compatible_node() calls with of_device_is_compatible().

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

1 files changed, 29 insertions, 21 deletions

diff --git a/arch/arm/mach-shmobile/timer.c b/arch/arm/mach-shmobile/timer.c
index 68bc0b82226d..942efdc82a62 100644
--- a/arch/arm/mach-shmobile/timer.c
+++ b/arch/arm/mach-shmobile/timer.c
@@ -59,29 +59,37 @@ void __init shmobile_setup_delay(unsigned int max_cpu_core_mhz,
 
 void __init shmobile_init_delay(void)
 {
-        struct device_node *np, *parent;
-        u32 max_freq, freq;
-
-        max_freq = 0;
-
-        parent = of_find_node_by_path("/cpus");
-        if (parent) {
-                for_each_child_of_node(parent, np) {
-                        if (!of_property_read_u32(np, "clock-frequency", &freq))
-                                max_freq = max(max_freq, freq);
-                }
-                of_node_put(parent);
-        }
+        struct device_node *np, *cpus;
+        bool is_a8_a9 = false;
+        bool is_a15 = false;
+        u32 max_freq = 0;
+
+        cpus = of_find_node_by_path("/cpus");
+        if (!cpus)
+                return;
+
+        for_each_child_of_node(cpus, np) {
+                u32 freq;
+
+                if (!of_property_read_u32(np, "clock-frequency", &freq))
+                        max_freq = max(max_freq, freq);
 
-        if (max_freq) {
-                if (of_find_compatible_node(NULL, NULL, "arm,cortex-a8"))
-                        shmobile_setup_delay_hz(max_freq, 1, 3);
-                else if (of_find_compatible_node(NULL, NULL, "arm,cortex-a9"))
-                        shmobile_setup_delay_hz(max_freq, 1, 3);
-                else if (of_find_compatible_node(NULL, NULL, "arm,cortex-a15"))
-                        if (!IS_ENABLED(CONFIG_ARM_ARCH_TIMER))
-                                shmobile_setup_delay_hz(max_freq, 2, 4);
+                if (of_device_is_compatible(np, "arm,cortex-a8") ||
+                    of_device_is_compatible(np, "arm,cortex-a9"))
+                        is_a8_a9 = true;
+                else if (of_device_is_compatible(np, "arm,cortex-a15"))
+                        is_a15 = true;
         }
+
+        of_node_put(cpus);
+
+        if (!max_freq)
+                return;
+
+        if (is_a8_a9)
+                shmobile_setup_delay_hz(max_freq, 1, 3);
+        else if (is_a15 && !IS_ENABLED(CONFIG_ARM_ARCH_TIMER))
+                shmobile_setup_delay_hz(max_freq, 2, 4);
 }
 
 static void __init shmobile_late_time_init(void)