diff options
Diffstat (limited to 'drivers/cpufreq/arm_big_little_dt.c')
-rw-r--r-- | drivers/cpufreq/arm_big_little_dt.c | 93 |
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 173ed059d95..fd9e3ea6a48 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"); |