1 files changed, 58 insertions, 36 deletions

diff --git a/drivers/cpufreq/arm_big_little_dt.c b/drivers/cpufreq/arm_big_little_dt.c
index 44be3115375c..fd9e3ea6a480 100644
--- a/drivers/cpufreq/arm_big_little_dt.c
+++ b/drivers/cpufreq/arm_big_little_dt.c
@@ -19,69 +19,75 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/cpu.h>
 #include <linux/cpufreq.h>
 #include <linux/device.h>
 #include <linux/export.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/opp.h>
+#include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 #include "arm_big_little.h"
 
-static int dt_init_opp_table(struct device *cpu_dev)
+/* get cpu node with valid operating-points */
+static struct device_node *get_cpu_node_with_valid_op(int cpu)
 {
-        struct device_node *np, *parent;
-        int count = 0, ret;
+        struct device_node *np = NULL, *parent;
+        int count = 0;
 
         parent = of_find_node_by_path("/cpus");
         if (!parent) {
                 pr_err("failed to find OF /cpus\n");
-                return -ENOENT;
+                return NULL;
         }
 
         for_each_child_of_node(parent, np) {
-                if (count++ != cpu_dev->id)
+                if (count++ != cpu)
                         continue;
                 if (!of_get_property(np, "operating-points", NULL)) {
-                        ret = -ENODATA;
-                } else {
-                        cpu_dev->of_node = np;
-                        ret = of_init_opp_table(cpu_dev);
+                        of_node_put(np);
+                        np = NULL;
                 }
-                of_node_put(np);
-                of_node_put(parent);
 
-                return ret;
+                break;
         }
 
-        return -ENODEV;
+        of_node_put(parent);
+        return np;
 }
 
-static int dt_get_transition_latency(struct device *cpu_dev)
+static int dt_init_opp_table(struct device *cpu_dev)
 {
-        struct device_node *np, *parent;
-        u32 transition_latency = CPUFREQ_ETERNAL;
-        int count = 0;
+        struct device_node *np;
+        int ret;
 
-        parent = of_find_node_by_path("/cpus");
-        if (!parent) {
-                pr_err("failed to find OF /cpus\n");
-                return -ENOENT;
-        }
+        np = get_cpu_node_with_valid_op(cpu_dev->id);
+        if (!np)
+                return -ENODATA;
 
-        for_each_child_of_node(parent, np) {
-                if (count++ != cpu_dev->id)
-                        continue;
+        cpu_dev->of_node = np;
+        ret = of_init_opp_table(cpu_dev);
+        of_node_put(np);
 
-                of_property_read_u32(np, "clock-latency", &transition_latency);
-                of_node_put(np);
-                of_node_put(parent);
+        return ret;
+}
 
-                return 0;
-        }
+static int dt_get_transition_latency(struct device *cpu_dev)
+{
+        struct device_node *np;
+        u32 transition_latency = CPUFREQ_ETERNAL;
+
+        np = get_cpu_node_with_valid_op(cpu_dev->id);
+        if (!np)
+                return CPUFREQ_ETERNAL;
 
-        return -ENODEV;
+        of_property_read_u32(np, "clock-latency", &transition_latency);
+        of_node_put(np);
+
+        pr_debug("%s: clock-latency: %d\n", __func__, transition_latency);
+        return transition_latency;
 }
 
 static struct cpufreq_arm_bL_ops dt_bL_ops = {
@@ -90,17 +96,33 @@ static struct cpufreq_arm_bL_ops dt_bL_ops = {
         .init_opp_table = dt_init_opp_table,
 };
 
-static int generic_bL_init(void)
+static int generic_bL_probe(struct platform_device *pdev)
 {
+        struct device_node *np;
+
+        np = get_cpu_node_with_valid_op(0);
+        if (!np)
+                return -ENODEV;
+
+        of_node_put(np);
         return bL_cpufreq_register(&dt_bL_ops);
 }
-module_init(generic_bL_init);
 
-static void generic_bL_exit(void)
+static int generic_bL_remove(struct platform_device *pdev)
 {
-        return bL_cpufreq_unregister(&dt_bL_ops);
+        bL_cpufreq_unregister(&dt_bL_ops);
+        return 0;
 }
-module_exit(generic_bL_exit);
+
+static struct platform_driver generic_bL_platdrv = {
+        .driver = {
+                .name   = "arm-bL-cpufreq-dt",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = generic_bL_probe,
+        .remove         = generic_bL_remove,
+};
+module_platform_driver(generic_bL_platdrv);
 
 MODULE_AUTHOR("Viresh Kumar <viresh.kumar@linaro.org>");
 MODULE_DESCRIPTION("Generic ARM big LITTLE cpufreq driver via DT");