1 files changed, 163 insertions, 79 deletions

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 861c100f9fac..6aa10de792b3 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -31,6 +31,8 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/devfreq.h>
 
+#define IS_SUPPORTED_FLAG(f, name) ((f & DEVFREQ_GOV_FLAG_##name) ? true : false)
+#define IS_SUPPORTED_ATTR(f, name) ((f & DEVFREQ_GOV_ATTR_##name) ? true : false)
 #define HZ_PER_KHZ	1000
 
 static struct class *devfreq_class;
@@ -367,6 +369,14 @@ static int devfreq_set_target(struct devfreq *devfreq, unsigned long new_freq,
 		return err;
 	}
 
+	/*
+	 * Print devfreq_frequency trace information between DEVFREQ_PRECHANGE
+	 * and DEVFREQ_POSTCHANGE because for showing the correct frequency
+	 * change order of between devfreq device and passive devfreq device.
+	 */
+	if (trace_devfreq_frequency_enabled() && new_freq != cur_freq)
+		trace_devfreq_frequency(devfreq, new_freq, cur_freq);
+
 	freqs.new = new_freq;
 	devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE);
 
@@ -382,18 +392,19 @@ static int devfreq_set_target(struct devfreq *devfreq, unsigned long new_freq,
 	return err;
 }
 
-/* Load monitoring helper functions for governors use */
-
 /**
- * update_devfreq() - Reevaluate the device and configure frequency.
+ * devfreq_update_target() - Reevaluate the device and configure frequency
+ *			   on the final stage.
  * @devfreq:	the devfreq instance.
+ * @freq:	the new frequency of parent device. This argument
+ *		is only used for devfreq device using passive governor.
  *
- * Note: Lock devfreq->lock before calling update_devfreq
- *	 This function is exported for governors.
+ * Note: Lock devfreq->lock before calling devfreq_update_target. This function
+ *	 should be only used by both update_devfreq() and devfreq governors.
  */
-int update_devfreq(struct devfreq *devfreq)
+int devfreq_update_target(struct devfreq *devfreq, unsigned long freq)
 {
-	unsigned long freq, min_freq, max_freq;
+	unsigned long min_freq, max_freq;
 	int err = 0;
 	u32 flags = 0;
 
@@ -418,7 +429,21 @@ int update_devfreq(struct devfreq *devfreq)
 	}
 
 	return devfreq_set_target(devfreq, freq, flags);
+}
+EXPORT_SYMBOL(devfreq_update_target);
 
+/* Load monitoring helper functions for governors use */
+
+/**
+ * update_devfreq() - Reevaluate the device and configure frequency.
+ * @devfreq:	the devfreq instance.
+ *
+ * Note: Lock devfreq->lock before calling update_devfreq
+ *	 This function is exported for governors.
+ */
+int update_devfreq(struct devfreq *devfreq)
+{
+	return devfreq_update_target(devfreq, 0L);
 }
 EXPORT_SYMBOL(update_devfreq);
 
@@ -456,7 +481,7 @@ static void devfreq_monitor(struct work_struct *work)
  */
 void devfreq_monitor_start(struct devfreq *devfreq)
 {
-	if (devfreq->governor->interrupt_driven)
+	if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN))
 		return;
 
 	switch (devfreq->profile->timer) {
@@ -486,7 +511,7 @@ EXPORT_SYMBOL(devfreq_monitor_start);
  */
 void devfreq_monitor_stop(struct devfreq *devfreq)
 {
-	if (devfreq->governor->interrupt_driven)
+	if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN))
 		return;
 
 	cancel_delayed_work_sync(&devfreq->work);
@@ -517,7 +542,7 @@ void devfreq_monitor_suspend(struct devfreq *devfreq)
 	devfreq->stop_polling = true;
 	mutex_unlock(&devfreq->lock);
 
-	if (devfreq->governor->interrupt_driven)
+	if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN))
 		return;
 
 	cancel_delayed_work_sync(&devfreq->work);
@@ -537,12 +562,13 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
 	unsigned long freq;
 
 	mutex_lock(&devfreq->lock);
-	if (!devfreq->stop_polling)
-		goto out;
 
-	if (devfreq->governor->interrupt_driven)
+	if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN))
 		goto out_update;
 
+	if (!devfreq->stop_polling)
+		goto out;
+
 	if (!delayed_work_pending(&devfreq->work) &&
 			devfreq->profile->polling_ms)
 		queue_delayed_work(devfreq_wq, &devfreq->work,
@@ -577,10 +603,10 @@ void devfreq_update_interval(struct devfreq *devfreq, unsigned int *delay)
 	mutex_lock(&devfreq->lock);
 	devfreq->profile->polling_ms = new_delay;
 
-	if (devfreq->stop_polling)
+	if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN))
 		goto out;
 
-	if (devfreq->governor->interrupt_driven)
+	if (devfreq->stop_polling)
 		goto out;
 
 	/* if new delay is zero, stop polling */
@@ -735,6 +761,11 @@ static void devfreq_dev_release(struct device *dev)
 	kfree(devfreq);
 }
 
+static void create_sysfs_files(struct devfreq *devfreq,
+				const struct devfreq_governor *gov);
+static void remove_sysfs_files(struct devfreq *devfreq,
+				const struct devfreq_governor *gov);
+
 /**
  * devfreq_add_device() - Add devfreq feature to the device
  * @dev:	the device to add devfreq feature.
@@ -780,7 +811,6 @@ struct devfreq *devfreq_add_device(struct device *dev,
 	devfreq->dev.release = devfreq_dev_release;
 	INIT_LIST_HEAD(&devfreq->node);
 	devfreq->profile = profile;
-	strscpy(devfreq->governor_name, governor_name, DEVFREQ_NAME_LEN);
 	devfreq->previous_freq = profile->initial_freq;
 	devfreq->last_status.current_frequency = profile->initial_freq;
 	devfreq->data = data;
@@ -876,7 +906,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
 
 	mutex_lock(&devfreq_list_lock);
 
-	governor = try_then_request_governor(devfreq->governor_name);
+	governor = try_then_request_governor(governor_name);
 	if (IS_ERR(governor)) {
 		dev_err(dev, "%s: Unable to find governor for the device\n",
 			__func__);
@@ -892,6 +922,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
 			__func__);
 		goto err_init;
 	}
+	create_sysfs_files(devfreq, devfreq->governor);
 
 	list_add(&devfreq->node, &devfreq_list);
 
@@ -922,9 +953,12 @@ int devfreq_remove_device(struct devfreq *devfreq)
 	if (!devfreq)
 		return -EINVAL;
 
-	if (devfreq->governor)
+	if (devfreq->governor) {
 		devfreq->governor->event_handler(devfreq,
 						 DEVFREQ_GOV_STOP, NULL);
+		remove_sysfs_files(devfreq, devfreq->governor);
+	}
+
 	device_unregister(&devfreq->dev);
 
 	return 0;
@@ -1214,7 +1248,7 @@ int devfreq_add_governor(struct devfreq_governor *governor)
 		int ret = 0;
 		struct device *dev = devfreq->dev.parent;
 
-		if (!strncmp(devfreq->governor_name, governor->name,
+		if (!strncmp(devfreq->governor->name, governor->name,
 			     DEVFREQ_NAME_LEN)) {
 			/* The following should never occur */
 			if (devfreq->governor) {
@@ -1276,7 +1310,7 @@ int devfreq_remove_governor(struct devfreq_governor *governor)
 		int ret;
 		struct device *dev = devfreq->dev.parent;
 
-		if (!strncmp(devfreq->governor_name, governor->name,
+		if (!strncmp(devfreq->governor->name, governor->name,
 			     DEVFREQ_NAME_LEN)) {
 			/* we should have a devfreq governor! */
 			if (!devfreq->governor) {
@@ -1347,36 +1381,53 @@ static ssize_t governor_store(struct device *dev, struct device_attribute *attr,
 	if (df->governor == governor) {
 		ret = 0;
 		goto out;
-	} else if (df->governor->immutable || governor->immutable) {
+	} else if (IS_SUPPORTED_FLAG(df->governor->flags, IMMUTABLE)
+		|| IS_SUPPORTED_FLAG(governor->flags, IMMUTABLE)) {
 		ret = -EINVAL;
 		goto out;
 	}
 
+	/*
+	 * Stop the current governor and remove the specific sysfs files
+	 * which depend on current governor.
+	 */
 	ret = df->governor->event_handler(df, DEVFREQ_GOV_STOP, NULL);
 	if (ret) {
 		dev_warn(dev, "%s: Governor %s not stopped(%d)\n",
 			 __func__, df->governor->name, ret);
 		goto out;
 	}
+	remove_sysfs_files(df, df->governor);
 
+	/*
+	 * Start the new governor and create the specific sysfs files
+	 * which depend on the new governor.
+	 */
 	prev_governor = df->governor;
 	df->governor = governor;
-	strncpy(df->governor_name, governor->name, DEVFREQ_NAME_LEN);
 	ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL);
 	if (ret) {
 		dev_warn(dev, "%s: Governor %s not started(%d)\n",
 			 __func__, df->governor->name, ret);
+
+		/* Restore previous governor */
 		df->governor = prev_governor;
-		strncpy(df->governor_name, prev_governor->name,
-			DEVFREQ_NAME_LEN);
 		ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL);
 		if (ret) {
 			dev_err(dev,
 				"%s: reverting to Governor %s failed (%d)\n",
-				__func__, df->governor_name, ret);
+				__func__, prev_governor->name, ret);
 			df->governor = NULL;
+			goto out;
 		}
 	}
+
+	/*
+	 * Create the sysfs files for the new governor. But if failed to start
+	 * the new governor, restore the sysfs files of previous governor.
+	 */
+	create_sysfs_files(df, df->governor);
+
 out:
 	mutex_unlock(&devfreq_list_lock);
 
@@ -1402,9 +1453,9 @@ static ssize_t available_governors_show(struct device *d,
 	 * The devfreq with immutable governor (e.g., passive) shows
 	 * only own governor.
 	 */
-	if (df->governor->immutable) {
+	if (IS_SUPPORTED_FLAG(df->governor->flags, IMMUTABLE)) {
 		count = scnprintf(&buf[count], DEVFREQ_NAME_LEN,
-				  "%s ", df->governor_name);
+				  "%s ", df->governor->name);
 	/*
 	 * The devfreq device shows the registered governor except for
 	 * immutable governors such as passive governor .
@@ -1413,7 +1464,7 @@ static ssize_t available_governors_show(struct device *d,
 		struct devfreq_governor *governor;
 
 		list_for_each_entry(governor, &devfreq_governor_list, node) {
-			if (governor->immutable)
+			if (IS_SUPPORTED_FLAG(governor->flags, IMMUTABLE))
 				continue;
 			count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
 					   "%s ", governor->name);
@@ -1458,39 +1509,6 @@ static ssize_t target_freq_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(target_freq);
 
-static ssize_t polling_interval_show(struct device *dev,
-				     struct device_attribute *attr, char *buf)
-{
-	struct devfreq *df = to_devfreq(dev);
-
-	if (!df->profile)
-		return -EINVAL;
-
-	return sprintf(buf, "%d\n", df->profile->polling_ms);
-}
-
-static ssize_t polling_interval_store(struct device *dev,
-				      struct device_attribute *attr,
-				      const char *buf, size_t count)
-{
-	struct devfreq *df = to_devfreq(dev);
-	unsigned int value;
-	int ret;
-
-	if (!df->governor)
-		return -EINVAL;
-
-	ret = sscanf(buf, "%u", &value);
-	if (ret != 1)
-		return -EINVAL;
-
-	df->governor->event_handler(df, DEVFREQ_GOV_UPDATE_INTERVAL, &value);
-	ret = count;
-
-	return ret;
-}
-static DEVICE_ATTR_RW(polling_interval);
-
 static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
 			      const char *buf, size_t count)
 {
@@ -1698,6 +1716,53 @@ static ssize_t trans_stat_store(struct device *dev,
 }
 static DEVICE_ATTR_RW(trans_stat);
 
+static struct attribute *devfreq_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_governor.attr,
+	&dev_attr_available_governors.attr,
+	&dev_attr_cur_freq.attr,
+	&dev_attr_available_frequencies.attr,
+	&dev_attr_target_freq.attr,
+	&dev_attr_min_freq.attr,
+	&dev_attr_max_freq.attr,
+	&dev_attr_trans_stat.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(devfreq);
+
+static ssize_t polling_interval_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct devfreq *df = to_devfreq(dev);
+
+	if (!df->profile)
+		return -EINVAL;
+
+	return sprintf(buf, "%d\n", df->profile->polling_ms);
+}
+
+static ssize_t polling_interval_store(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf, size_t count)
+{
+	struct devfreq *df = to_devfreq(dev);
+	unsigned int value;
+	int ret;
+
+	if (!df->governor)
+		return -EINVAL;
+
+	ret = sscanf(buf, "%u", &value);
+	if (ret != 1)
+		return -EINVAL;
+
+	df->governor->event_handler(df, DEVFREQ_GOV_UPDATE_INTERVAL, &value);
+	ret = count;
+
+	return ret;
+}
+static DEVICE_ATTR_RW(polling_interval);
+
 static ssize_t timer_show(struct device *dev,
 			     struct device_attribute *attr, char *buf)
 {
@@ -1761,21 +1826,36 @@ out:
 }
 static DEVICE_ATTR_RW(timer);
 
-static struct attribute *devfreq_attrs[] = {
-	&dev_attr_name.attr,
-	&dev_attr_governor.attr,
-	&dev_attr_available_governors.attr,
-	&dev_attr_cur_freq.attr,
-	&dev_attr_available_frequencies.attr,
-	&dev_attr_target_freq.attr,
-	&dev_attr_polling_interval.attr,
-	&dev_attr_min_freq.attr,
-	&dev_attr_max_freq.attr,
-	&dev_attr_trans_stat.attr,
-	&dev_attr_timer.attr,
-	NULL,
-};
-ATTRIBUTE_GROUPS(devfreq);
+#define CREATE_SYSFS_FILE(df, name)					\
+{									\
+	int ret;							\
+	ret = sysfs_create_file(&df->dev.kobj, &dev_attr_##name.attr);	\
+	if (ret < 0) {							\
+		dev_warn(&df->dev,					\
+			"Unable to create attr(%s)\n", "##name");	\
+	}								\
+}									\
+
+/* Create the specific sysfs files which depend on each governor. */
+static void create_sysfs_files(struct devfreq *devfreq,
+				const struct devfreq_governor *gov)
+{
+	if (IS_SUPPORTED_ATTR(gov->attrs, POLLING_INTERVAL))
+		CREATE_SYSFS_FILE(devfreq, polling_interval);
+	if (IS_SUPPORTED_ATTR(gov->attrs, TIMER))
+		CREATE_SYSFS_FILE(devfreq, timer);
+}
+
+/* Remove the specific sysfs files which depend on each governor. */
+static void remove_sysfs_files(struct devfreq *devfreq,
+				const struct devfreq_governor *gov)
+{
+	if (IS_SUPPORTED_ATTR(gov->attrs, POLLING_INTERVAL))
+		sysfs_remove_file(&devfreq->dev.kobj,
+				&dev_attr_polling_interval.attr);
+	if (IS_SUPPORTED_ATTR(gov->attrs, TIMER))
+		sysfs_remove_file(&devfreq->dev.kobj, &dev_attr_timer.attr);
+}
 
 /**
  * devfreq_summary_show() - Show the summary of the devfreq devices
@@ -1818,7 +1898,7 @@ static int devfreq_summary_show(struct seq_file *s, void *data)
 
 	list_for_each_entry_reverse(devfreq, &devfreq_list, node) {
 #if IS_ENABLED(CONFIG_DEVFREQ_GOV_PASSIVE)
-		if (!strncmp(devfreq->governor_name, DEVFREQ_GOV_PASSIVE,
+		if (!strncmp(devfreq->governor->name, DEVFREQ_GOV_PASSIVE,
 							DEVFREQ_NAME_LEN)) {
 			struct devfreq_passive_data *data = devfreq->data;
 
@@ -1832,15 +1912,19 @@ static int devfreq_summary_show(struct seq_file *s, void *data)
 		mutex_lock(&devfreq->lock);
 		cur_freq = devfreq->previous_freq;
 		get_freq_range(devfreq, &min_freq, &max_freq);
-		polling_ms = devfreq->profile->polling_ms;
 		timer = devfreq->profile->timer;
+
+		if (IS_SUPPORTED_ATTR(devfreq->governor->attrs, POLLING_INTERVAL))
+			polling_ms = devfreq->profile->polling_ms;
+		else
+			polling_ms = 0;
 		mutex_unlock(&devfreq->lock);
 
 		seq_printf(s,
 			"%-30s %-30s %-15s %-10s %10d %12ld %12ld %12ld\n",
 			dev_name(&devfreq->dev),
 			p_devfreq ? dev_name(&p_devfreq->dev) : "null",
-			devfreq->governor_name,
+			devfreq->governor->name,
 			polling_ms ? timer_name[timer] : "null",
 			polling_ms,
 			cur_freq,