zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/drivers/cpufreq/cpufreq_userspace.c b/ap/os/linux/linux-3.4.x/drivers/cpufreq/cpufreq_userspace.c
new file mode 100644
index 0000000..bedac1a
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/drivers/cpufreq/cpufreq_userspace.c
@@ -0,0 +1,222 @@
+
+/*
+ * linux/drivers/cpufreq/cpufreq_userspace.c
+ *
+ * Copyright (C) 2001 Russell King
+ * (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/cpufreq.h>
+#include <linux/cpu.h>
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/sysfs.h>
+#include <linux/mutex.h>
+
+/**
+ * A few values needed by the userspace governor
+ */
+static DEFINE_PER_CPU(unsigned int, cpu_max_freq);
+static DEFINE_PER_CPU(unsigned int, cpu_min_freq);
+static DEFINE_PER_CPU(unsigned int, cpu_cur_freq); /* current CPU freq */
+static DEFINE_PER_CPU(unsigned int, cpu_set_freq); /* CPU freq desired by
+ userspace */
+static DEFINE_PER_CPU(unsigned int, cpu_is_managed);
+
+static DEFINE_MUTEX(userspace_mutex);
+static int cpus_using_userspace_governor;
+
+/* keep track of frequency transitions */
+static int
+userspace_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
+ void *data)
+{
+ struct cpufreq_freqs *freq = data;
+
+ if (!per_cpu(cpu_is_managed, freq->cpu))
+ return 0;
+
+ if (val == CPUFREQ_POSTCHANGE) {
+ pr_debug("saving cpu_cur_freq of cpu %u to be %u kHz\n",
+ freq->cpu, freq->new);
+ per_cpu(cpu_cur_freq, freq->cpu) = freq->new;
+ }
+
+ return 0;
+}
+
+static struct notifier_block userspace_cpufreq_notifier_block = {
+ .notifier_call = userspace_cpufreq_notifier
+};
+
+
+/**
+ * cpufreq_set - set the CPU frequency
+ * @policy: pointer to policy struct where freq is being set
+ * @freq: target frequency in kHz
+ *
+ * Sets the CPU frequency to freq.
+ */
+static int cpufreq_set(struct cpufreq_policy *policy, unsigned int freq)
+{
+ int ret = -EINVAL;
+
+ pr_debug("cpufreq_set for cpu %u, freq %u kHz\n", policy->cpu, freq);
+
+ mutex_lock(&userspace_mutex);
+ if (!per_cpu(cpu_is_managed, policy->cpu))
+ goto err;
+
+ per_cpu(cpu_set_freq, policy->cpu) = freq;
+
+ if (freq < per_cpu(cpu_min_freq, policy->cpu))
+ freq = per_cpu(cpu_min_freq, policy->cpu);
+ if (freq > per_cpu(cpu_max_freq, policy->cpu))
+ freq = per_cpu(cpu_max_freq, policy->cpu);
+
+ /*
+ * We're safe from concurrent calls to ->target() here
+ * as we hold the userspace_mutex lock. If we were calling
+ * cpufreq_driver_target, a deadlock situation might occur:
+ * A: cpufreq_set (lock userspace_mutex) ->
+ * cpufreq_driver_target(lock policy->lock)
+ * B: cpufreq_set_policy(lock policy->lock) ->
+ * __cpufreq_governor ->
+ * cpufreq_governor_userspace (lock userspace_mutex)
+ */
+ ret = __cpufreq_driver_target(policy, freq, CPUFREQ_RELATION_L);
+
+ err:
+ mutex_unlock(&userspace_mutex);
+ return ret;
+}
+
+
+static ssize_t show_speed(struct cpufreq_policy *policy, char *buf)
+{
+ return sprintf(buf, "%u\n", per_cpu(cpu_cur_freq, policy->cpu));
+}
+
+static int cpufreq_governor_userspace(struct cpufreq_policy *policy,
+ unsigned int event)
+{
+ unsigned int cpu = policy->cpu;
+ int rc = 0;
+
+ switch (event) {
+ case CPUFREQ_GOV_START:
+ if (!cpu_online(cpu))
+ return -EINVAL;
+ BUG_ON(!policy->cur);
+ mutex_lock(&userspace_mutex);
+
+ if (cpus_using_userspace_governor == 0) {
+ cpufreq_register_notifier(
+ &userspace_cpufreq_notifier_block,
+ CPUFREQ_TRANSITION_NOTIFIER);
+ }
+ cpus_using_userspace_governor++;
+
+ per_cpu(cpu_is_managed, cpu) = 1;
+ per_cpu(cpu_min_freq, cpu) = policy->min;
+ per_cpu(cpu_max_freq, cpu) = policy->max;
+ per_cpu(cpu_cur_freq, cpu) = policy->cur;
+ per_cpu(cpu_set_freq, cpu) = policy->cur;
+ pr_debug("managing cpu %u started "
+ "(%u - %u kHz, currently %u kHz)\n",
+ cpu,
+ per_cpu(cpu_min_freq, cpu),
+ per_cpu(cpu_max_freq, cpu),
+ per_cpu(cpu_cur_freq, cpu));
+
+ mutex_unlock(&userspace_mutex);
+ break;
+ case CPUFREQ_GOV_STOP:
+ mutex_lock(&userspace_mutex);
+ cpus_using_userspace_governor--;
+ if (cpus_using_userspace_governor == 0) {
+ cpufreq_unregister_notifier(
+ &userspace_cpufreq_notifier_block,
+ CPUFREQ_TRANSITION_NOTIFIER);
+ }
+
+ per_cpu(cpu_is_managed, cpu) = 0;
+ per_cpu(cpu_min_freq, cpu) = 0;
+ per_cpu(cpu_max_freq, cpu) = 0;
+ per_cpu(cpu_set_freq, cpu) = 0;
+ pr_debug("managing cpu %u stopped\n", cpu);
+ mutex_unlock(&userspace_mutex);
+ break;
+ case CPUFREQ_GOV_LIMITS:
+ mutex_lock(&userspace_mutex);
+ pr_debug("limit event for cpu %u: %u - %u kHz, "
+ "currently %u kHz, last set to %u kHz\n",
+ cpu, policy->min, policy->max,
+ per_cpu(cpu_cur_freq, cpu),
+ per_cpu(cpu_set_freq, cpu));
+ if (policy->max < per_cpu(cpu_set_freq, cpu)) {
+ __cpufreq_driver_target(policy, policy->max,
+ CPUFREQ_RELATION_H);
+ } else if (policy->min > per_cpu(cpu_set_freq, cpu)) {
+ __cpufreq_driver_target(policy, policy->min,
+ CPUFREQ_RELATION_L);
+ } else {
+ __cpufreq_driver_target(policy,
+ per_cpu(cpu_set_freq, cpu),
+ CPUFREQ_RELATION_L);
+ }
+ per_cpu(cpu_min_freq, cpu) = policy->min;
+ per_cpu(cpu_max_freq, cpu) = policy->max;
+ per_cpu(cpu_cur_freq, cpu) = policy->cur;
+ mutex_unlock(&userspace_mutex);
+ break;
+ }
+ return rc;
+}
+
+
+#ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE
+static
+#endif
+struct cpufreq_governor cpufreq_gov_userspace = {
+ .name = "userspace",
+ .governor = cpufreq_governor_userspace,
+ .store_setspeed = cpufreq_set,
+ .show_setspeed = show_speed,
+ .owner = THIS_MODULE,
+};
+
+static int __init cpufreq_gov_userspace_init(void)
+{
+ return cpufreq_register_governor(&cpufreq_gov_userspace);
+}
+
+
+static void __exit cpufreq_gov_userspace_exit(void)
+{
+ cpufreq_unregister_governor(&cpufreq_gov_userspace);
+}
+
+
+MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>, "
+ "Russell King <rmk@arm.linux.org.uk>");
+MODULE_DESCRIPTION("CPUfreq policy governor 'userspace'");
+MODULE_LICENSE("GPL");
+
+#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE
+fs_initcall(cpufreq_gov_userspace_init);
+#else
+module_init(cpufreq_gov_userspace_init);
+#endif
+module_exit(cpufreq_gov_userspace_exit);