Cpufreq: Added input event hook to ramp up cpu frequency

This will cause switch to maximum opp immediately when user
interaction occurs, i.e. touchscreen input or keypad activity.

Change-Id: I0cfe32479ef62a967f359c1bf57f97eefde7e8f7
Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com>
[bsteuer@quicinc.com: fixed cpu_dbs_info naming, added header]
Signed-off-by: Brian Steuer <bsteuer@codeaurora.org>

drivers/cpufreq/cpufreq.c

@@ -72,7 +72,7 @@ static DEFINE_PER_CPU(int, cpufreq_policy_cpu);
 static DEFINE_PER_CPU(struct rw_semaphore, cpu_policy_rwsem);
 
 #define lock_policy_rwsem(mode, cpu)					\
-static int lock_policy_rwsem_##mode					\
+int lock_policy_rwsem_##mode						\
 (int cpu)								\
 {									\
 	int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu);		\
@@ -97,7 +97,7 @@ static void unlock_policy_rwsem_read(int cpu)
 	up_read(&per_cpu(cpu_policy_rwsem, policy_cpu));
 }
 
-static void unlock_policy_rwsem_write(int cpu)
+void unlock_policy_rwsem_write(int cpu)
 {
 	int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu);
 	BUG_ON(policy_cpu == -1);

drivers/cpufreq/cpufreq_ondemand.c

@@ -22,6 +22,9 @@
 #include <linux/tick.h>
 #include <linux/ktime.h>
 #include <linux/sched.h>
+#include <linux/input.h>
+#include <linux/workqueue.h>
+#include <linux/slab.h>
 
 /*
  * dbs is used in this file as a shortform for demandbased switching
@@ -705,6 +708,86 @@ static int should_io_be_busy(void)
 	return 0;
 }
 
+static void dbs_refresh_callback(struct work_struct *unused)
+{
+	struct cpufreq_policy *policy;
+	struct cpu_dbs_info_s *this_dbs_info;
+
+	if (lock_policy_rwsem_write(0) < 0)
+		return;
+
+	this_dbs_info = &per_cpu(od_cpu_dbs_info, 0);
+	policy = this_dbs_info->cur_policy;
+
+	if (policy->cur < policy->max) {
+		policy->cur = policy->max;
+
+		__cpufreq_driver_target(policy, policy->max,
+					CPUFREQ_RELATION_L);
+		this_dbs_info->prev_cpu_idle = get_cpu_idle_time(0,
+				&this_dbs_info->prev_cpu_wall);
+	}
+	unlock_policy_rwsem_write(0);
+}
+
+static DECLARE_WORK(dbs_refresh_work, dbs_refresh_callback);
+
+static void dbs_input_event(struct input_handle *handle, unsigned int type,
+		unsigned int code, int value)
+{
+	schedule_work(&dbs_refresh_work);
+}
+
+static int dbs_input_connect(struct input_handler *handler,
+		struct input_dev *dev, const struct input_device_id *id)
+{
+	struct input_handle *handle;
+	int error;
+
+	handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
+	if (!handle)
+		return -ENOMEM;
+
+	handle->dev = dev;
+	handle->handler = handler;
+	handle->name = "cpufreq";
+
+	error = input_register_handle(handle);
+	if (error)
+		goto err2;
+
+	error = input_open_device(handle);
+	if (error)
+		goto err1;
+
+	return 0;
+err1:
+	input_unregister_handle(handle);
+err2:
+	kfree(handle);
+	return error;
+}
+
+static void dbs_input_disconnect(struct input_handle *handle)
+{
+	input_close_device(handle);
+	input_unregister_handle(handle);
+	kfree(handle);
+}
+
+static const struct input_device_id dbs_ids[] = {
+	{ .driver_info = 1 },
+	{ },
+};
+
+static struct input_handler dbs_input_handler = {
+	.event		= dbs_input_event,
+	.connect	= dbs_input_connect,
+	.disconnect	= dbs_input_disconnect,
+	.name		= "cpufreq_ond",
+	.id_table	= dbs_ids,
+};
+
 static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
 				   unsigned int event)
 {
@@ -763,6 +846,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
 				    latency * LATENCY_MULTIPLIER);
 			dbs_tuners_ins.io_is_busy = should_io_be_busy();
 		}
+		rc = input_register_handler(&dbs_input_handler);
 		mutex_unlock(&dbs_mutex);
 
 		mutex_init(&this_dbs_info->timer_mutex);
@@ -775,6 +859,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
 		mutex_lock(&dbs_mutex);
 		mutex_destroy(&this_dbs_info->timer_mutex);
 		dbs_enable--;
+		input_unregister_handler(&dbs_input_handler);
 		mutex_unlock(&dbs_mutex);
 		if (!dbs_enable)
 			sysfs_remove_group(cpufreq_global_kobject,

include/linux/cpufreq.h

@@ -205,6 +205,8 @@ extern int __cpufreq_driver_getavg(struct cpufreq_policy *policy,
 int cpufreq_register_governor(struct cpufreq_governor *governor);
 void cpufreq_unregister_governor(struct cpufreq_governor *governor);
 
+int lock_policy_rwsem_write(int cpu);
+void unlock_policy_rwsem_write(int cpu);
 
 /*********************************************************************
  *                      CPUFREQ DRIVER INTERFACE                     *