[PATCH v4 2/3] devfreq: Add suspend and resume apis

From: Rajagopal Venkat
Date: Thu Oct 04 2012 - 05:32:24 EST


Add devfreq suspend/resume apis for devfreq users. This patch
supports suspend and resume of devfreq load monitoring, required
for devices which can idle.

Signed-off-by: Rajagopal Venkat <rajagopal.venkat@xxxxxxxxxx>
Acked-by: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
---
drivers/devfreq/devfreq.c | 28 ++++++++++++++++++++++++++++
drivers/devfreq/governor.h | 2 ++
drivers/devfreq/governor_simpleondemand.c | 9 +++++++++
include/linux/devfreq.h | 12 ++++++++++++
4 files changed, 51 insertions(+)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 41a4099..63e075e 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -428,6 +428,34 @@ int devfreq_remove_device(struct devfreq *devfreq)
}
EXPORT_SYMBOL(devfreq_remove_device);

+/**
+ * devfreq_suspend_device() - Suspend devfreq of a device.
+ * @devfreq the devfreq instance to be suspended
+ */
+int devfreq_suspend_device(struct devfreq *devfreq)
+{
+ if (!devfreq)
+ return -EINVAL;
+
+ return devfreq->governor->event_handler(devfreq,
+ DEVFREQ_GOV_SUSPEND, NULL);
+}
+EXPORT_SYMBOL(devfreq_suspend_device);
+
+/**
+ * devfreq_resume_device() - Resume devfreq of a device.
+ * @devfreq the devfreq instance to be resumed
+ */
+int devfreq_resume_device(struct devfreq *devfreq)
+{
+ if (!devfreq)
+ return -EINVAL;
+
+ return devfreq->governor->event_handler(devfreq,
+ DEVFREQ_GOV_RESUME, NULL);
+}
+EXPORT_SYMBOL(devfreq_resume_device);
+
static ssize_t show_governor(struct device *dev,
struct device_attribute *attr, char *buf)
{
diff --git a/drivers/devfreq/governor.h b/drivers/devfreq/governor.h
index bb3aff3..26432ac 100644
--- a/drivers/devfreq/governor.h
+++ b/drivers/devfreq/governor.h
@@ -22,6 +22,8 @@
#define DEVFREQ_GOV_START 0x1
#define DEVFREQ_GOV_STOP 0x2
#define DEVFREQ_GOV_INTERVAL 0x3
+#define DEVFREQ_GOV_SUSPEND 0x4
+#define DEVFREQ_GOV_RESUME 0x5

/* Caution: devfreq->lock must be locked before calling update_devfreq */
extern int update_devfreq(struct devfreq *devfreq);
diff --git a/drivers/devfreq/governor_simpleondemand.c b/drivers/devfreq/governor_simpleondemand.c
index cf94218..a8ba78c 100644
--- a/drivers/devfreq/governor_simpleondemand.c
+++ b/drivers/devfreq/governor_simpleondemand.c
@@ -104,6 +104,15 @@ int devfreq_simple_ondemand_handler(struct devfreq *devfreq,
case DEVFREQ_GOV_INTERVAL:
devfreq_interval_update(devfreq, (unsigned int *)data);
break;
+
+ case DEVFREQ_GOV_SUSPEND:
+ devfreq_monitor_suspend(devfreq);
+ break;
+
+ case DEVFREQ_GOV_RESUME:
+ devfreq_monitor_resume(devfreq);
+ break;
+
default:
break;
}
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index 9cdffde..ee243a3 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -158,6 +158,8 @@ extern struct devfreq *devfreq_add_device(struct device *dev,
const struct devfreq_governor *governor,
void *data);
extern int devfreq_remove_device(struct devfreq *devfreq);
+extern int devfreq_suspend_device(struct devfreq *devfreq);
+extern int devfreq_resume_device(struct devfreq *devfreq);

/* Helper functions for devfreq user device driver with OPP. */
extern struct opp *devfreq_recommended_opp(struct device *dev,
@@ -211,6 +213,16 @@ static int devfreq_remove_device(struct devfreq *devfreq)
return 0;
}

+static int devfreq_suspend_device(struct devfreq *devfreq)
+{
+ return 0;
+}
+
+static int devfreq_resume_device(struct devfreq *devfreq)
+{
+ return 0;
+}
+
static struct opp *devfreq_recommended_opp(struct device *dev,
unsigned long *freq, u32 flags)
{
--
1.7.11.3

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