1 files changed, 57 insertions, 36 deletions

diff --git a/drivers/cpufreq/arm_big_little_dt.c b/drivers/cpufreq/arm_big_little_dt.c
index 173ed059d95f..fd9e3ea6a480 100644
--- a/drivers/cpufreq/arm_big_little_dt.c
+++ b/drivers/cpufreq/arm_big_little_dt.c
@@ -19,70 +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_init_opp_table(struct device *cpu_dev)
+{
+	struct device_node *np;
+	int ret;
+
+	np = get_cpu_node_with_valid_op(cpu_dev->id);
+	if (!np)
+		return -ENODATA;
+
+	cpu_dev->of_node = np;
+	ret = of_init_opp_table(cpu_dev);
+	of_node_put(np);
+
+	return ret;
 }
 
 static int dt_get_transition_latency(struct device *cpu_dev)
 {
-	struct device_node *np, *parent;
+	struct device_node *np;
 	u32 transition_latency = CPUFREQ_ETERNAL;
-	int count = 0;
 
-	parent = of_find_node_by_path("/cpus");
-	if (!parent) {
-		pr_info("Failed to find OF /cpus. Use CPUFREQ_ETERNAL transition latency\n");
+	np = get_cpu_node_with_valid_op(cpu_dev->id);
+	if (!np)
 		return CPUFREQ_ETERNAL;
-	}
-
-	for_each_child_of_node(parent, np) {
-		if (count++ != cpu_dev->id)
-			continue;
 
-		of_property_read_u32(np, "clock-latency", &transition_latency);
-		of_node_put(np);
-		of_node_put(parent);
+	of_property_read_u32(np, "clock-latency", &transition_latency);
+	of_node_put(np);
 
-		return transition_latency;
-	}
-
-	pr_info("clock-latency isn't found, use CPUFREQ_ETERNAL transition latency\n");
-	return CPUFREQ_ETERNAL;
+	pr_debug("%s: clock-latency: %d\n", __func__, transition_latency);
+	return transition_latency;
 }
 
 static struct cpufreq_arm_bL_ops dt_bL_ops = {
@@ -91,17 +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");