PM / devfreq: add relation of recommended frequency.

[cascardo/linux.git] / drivers / devfreq / devfreq.c

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index c189b82..70c31d4 100644 (file)
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -83,6 +83,7 @@ int update_devfreq(struct devfreq *devfreq)
 {
        unsigned long freq;
        int err = 0;
+       u32 flags = 0;
 
        if (!mutex_is_locked(&devfreq->lock)) {
                WARN(true, "devfreq->lock must be locked by the caller.\n");
@@ -94,7 +95,24 @@ int update_devfreq(struct devfreq *devfreq)
        if (err)
                return err;
 
-       err = devfreq->profile->target(devfreq->dev.parent, &freq);
+       /*
+        * Adjust the freuqency with user freq and QoS.
+        *
+        * List from the highest proiority
+        * max_freq (probably called by thermal when it's too hot)
+        * min_freq
+        */
+
+       if (devfreq->min_freq && freq < devfreq->min_freq) {
+               freq = devfreq->min_freq;
+               flags &= ~DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use GLB */
+       }
+       if (devfreq->max_freq && freq > devfreq->max_freq) {
+               freq = devfreq->max_freq;
+               flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */
+       }
+
+       err = devfreq->profile->target(devfreq->dev.parent, &freq, flags);
        if (err)
                return err;
 
@@ -501,12 +519,82 @@ static ssize_t show_central_polling(struct device *dev,
                       !to_devfreq(dev)->governor->no_central_polling);
 }
 
+static ssize_t store_min_freq(struct device *dev, struct device_attribute *attr,
+                             const char *buf, size_t count)
+{
+       struct devfreq *df = to_devfreq(dev);
+       unsigned long value;
+       int ret;
+       unsigned long max;
+
+       ret = sscanf(buf, "%lu", &value);
+       if (ret != 1)
+               goto out;
+
+       mutex_lock(&df->lock);
+       max = df->max_freq;
+       if (value && max && value > max) {
+               ret = -EINVAL;
+               goto unlock;
+       }
+
+       df->min_freq = value;
+       update_devfreq(df);
+       ret = count;
+unlock:
+       mutex_unlock(&df->lock);
+out:
+       return ret;
+}
+
+static ssize_t show_min_freq(struct device *dev, struct device_attribute *attr,
+                            char *buf)
+{
+       return sprintf(buf, "%lu\n", to_devfreq(dev)->min_freq);
+}
+
+static ssize_t store_max_freq(struct device *dev, struct device_attribute *attr,
+                             const char *buf, size_t count)
+{
+       struct devfreq *df = to_devfreq(dev);
+       unsigned long value;
+       int ret;
+       unsigned long min;
+
+       ret = sscanf(buf, "%lu", &value);
+       if (ret != 1)
+               goto out;
+
+       mutex_lock(&df->lock);
+       min = df->min_freq;
+       if (value && min && value < min) {
+               ret = -EINVAL;
+               goto unlock;
+       }
+
+       df->max_freq = value;
+       update_devfreq(df);
+       ret = count;
+unlock:
+       mutex_unlock(&df->lock);
+out:
+       return ret;
+}
+
+static ssize_t show_max_freq(struct device *dev, struct device_attribute *attr,
+                            char *buf)
+{
+       return sprintf(buf, "%lu\n", to_devfreq(dev)->max_freq);
+}
+
 static struct device_attribute devfreq_attrs[] = {
        __ATTR(governor, S_IRUGO, show_governor, NULL),
        __ATTR(cur_freq, S_IRUGO, show_freq, NULL),
        __ATTR(central_polling, S_IRUGO, show_central_polling, NULL),
        __ATTR(polling_interval, S_IRUGO | S_IWUSR, show_polling_interval,
               store_polling_interval),
+       __ATTR(min_freq, S_IRUGO | S_IWUSR, show_min_freq, store_min_freq),
+       __ATTR(max_freq, S_IRUGO | S_IWUSR, show_max_freq, store_max_freq),
        { },
 };
 
@@ -555,14 +643,30 @@ module_exit(devfreq_exit);
  *                          freq value given to target callback.
  * @dev                The devfreq user device. (parent of devfreq)
  * @freq       The frequency given to target function
+ * @flags      Flags handed from devfreq framework.
  *
  */
-struct opp *devfreq_recommended_opp(struct device *dev, unsigned long *freq)
+struct opp *devfreq_recommended_opp(struct device *dev, unsigned long *freq,
+                                   u32 flags)
 {
-       struct opp *opp = opp_find_freq_ceil(dev, freq);
+       struct opp *opp;
 
-       if (opp == ERR_PTR(-ENODEV))
+       if (flags & DEVFREQ_FLAG_LEAST_UPPER_BOUND) {
+               /* The freq is an upper bound. opp should be lower */
                opp = opp_find_freq_floor(dev, freq);
+
+               /* If not available, use the closest opp */
+               if (opp == ERR_PTR(-ENODEV))
+                       opp = opp_find_freq_ceil(dev, freq);
+       } else {
+               /* The freq is an lower bound. opp should be higher */
+               opp = opp_find_freq_ceil(dev, freq);
+
+               /* If not available, use the closest opp */
+               if (opp == ERR_PTR(-ENODEV))
+                       opp = opp_find_freq_floor(dev, freq);
+       }
+
        return opp;
 }