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Diffstat (limited to 'drivers/cpufreq/arm_big_little_dt.c')
-rw-r--r--drivers/cpufreq/arm_big_little_dt.c94
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 44be311..fd9e3ea 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");
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