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Diffstat (limited to 'drivers/base/power/opp.c')
-rw-r--r--drivers/base/power/opp.c122
1 files changed, 26 insertions, 96 deletions
diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c
index 25538675d59e..89ced955fafa 100644
--- a/drivers/base/power/opp.c
+++ b/drivers/base/power/opp.c
@@ -15,7 +15,6 @@
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/slab.h>
-#include <linux/cpufreq.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/rculist.h>
@@ -394,6 +393,13 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor);
* to keep the integrity of the internal data structures. Callers should ensure
* that this function is *NOT* called under RCU protection or in contexts where
* mutex cannot be locked.
+ *
+ * Return:
+ * 0: On success OR
+ * Duplicate OPPs (both freq and volt are same) and opp->available
+ * -EEXIST: Freq are same and volt are different OR
+ * Duplicate OPPs (both freq and volt are same) and !opp->available
+ * -ENOMEM: Memory allocation failure
*/
int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
{
@@ -443,15 +449,31 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
new_opp->u_volt = u_volt;
new_opp->available = true;
- /* Insert new OPP in order of increasing frequency */
+ /*
+ * Insert new OPP in order of increasing frequency
+ * and discard if already present
+ */
head = &dev_opp->opp_list;
list_for_each_entry_rcu(opp, &dev_opp->opp_list, node) {
- if (new_opp->rate < opp->rate)
+ if (new_opp->rate <= opp->rate)
break;
else
head = &opp->node;
}
+ /* Duplicate OPPs ? */
+ if (new_opp->rate == opp->rate) {
+ int ret = opp->available && new_opp->u_volt == opp->u_volt ?
+ 0 : -EEXIST;
+
+ dev_warn(dev, "%s: duplicate OPPs detected. Existing: freq: %lu, volt: %lu, enabled: %d. New: freq: %lu, volt: %lu, enabled: %d\n",
+ __func__, opp->rate, opp->u_volt, opp->available,
+ new_opp->rate, new_opp->u_volt, new_opp->available);
+ mutex_unlock(&dev_opp_list_lock);
+ kfree(new_opp);
+ return ret;
+ }
+
list_add_rcu(&new_opp->node, head);
mutex_unlock(&dev_opp_list_lock);
@@ -596,96 +618,6 @@ int dev_pm_opp_disable(struct device *dev, unsigned long freq)
}
EXPORT_SYMBOL_GPL(dev_pm_opp_disable);
-#ifdef CONFIG_CPU_FREQ
-/**
- * dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device
- * @dev: device for which we do this operation
- * @table: Cpufreq table returned back to caller
- *
- * Generate a cpufreq table for a provided device- this assumes that the
- * opp list is already initialized and ready for usage.
- *
- * This function allocates required memory for the cpufreq table. It is
- * expected that the caller does the required maintenance such as freeing
- * the table as required.
- *
- * Returns -EINVAL for bad pointers, -ENODEV if the device is not found, -ENOMEM
- * if no memory available for the operation (table is not populated), returns 0
- * if successful and table is populated.
- *
- * WARNING: It is important for the callers to ensure refreshing their copy of
- * the table if any of the mentioned functions have been invoked in the interim.
- *
- * Locking: The internal device_opp and opp structures are RCU protected.
- * To simplify the logic, we pretend we are updater and hold relevant mutex here
- * Callers should ensure that this function is *NOT* called under RCU protection
- * or in contexts where mutex locking cannot be used.
- */
-int dev_pm_opp_init_cpufreq_table(struct device *dev,
- struct cpufreq_frequency_table **table)
-{
- struct device_opp *dev_opp;
- struct dev_pm_opp *opp;
- struct cpufreq_frequency_table *freq_table;
- int i = 0;
-
- /* Pretend as if I am an updater */
- mutex_lock(&dev_opp_list_lock);
-
- dev_opp = find_device_opp(dev);
- if (IS_ERR(dev_opp)) {
- int r = PTR_ERR(dev_opp);
- mutex_unlock(&dev_opp_list_lock);
- dev_err(dev, "%s: Device OPP not found (%d)\n", __func__, r);
- return r;
- }
-
- freq_table = kzalloc(sizeof(struct cpufreq_frequency_table) *
- (dev_pm_opp_get_opp_count(dev) + 1), GFP_KERNEL);
- if (!freq_table) {
- mutex_unlock(&dev_opp_list_lock);
- dev_warn(dev, "%s: Unable to allocate frequency table\n",
- __func__);
- return -ENOMEM;
- }
-
- list_for_each_entry(opp, &dev_opp->opp_list, node) {
- if (opp->available) {
- freq_table[i].driver_data = i;
- freq_table[i].frequency = opp->rate / 1000;
- i++;
- }
- }
- mutex_unlock(&dev_opp_list_lock);
-
- freq_table[i].driver_data = i;
- freq_table[i].frequency = CPUFREQ_TABLE_END;
-
- *table = &freq_table[0];
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(dev_pm_opp_init_cpufreq_table);
-
-/**
- * dev_pm_opp_free_cpufreq_table() - free the cpufreq table
- * @dev: device for which we do this operation
- * @table: table to free
- *
- * Free up the table allocated by dev_pm_opp_init_cpufreq_table
- */
-void dev_pm_opp_free_cpufreq_table(struct device *dev,
- struct cpufreq_frequency_table **table)
-{
- if (!table)
- return;
-
- kfree(*table);
- *table = NULL;
-}
-EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table);
-#endif /* CONFIG_CPU_FREQ */
-
/**
* dev_pm_opp_get_notifier() - find notifier_head of the device with opp
* @dev: device pointer used to lookup device OPPs.
@@ -734,11 +666,9 @@ int of_init_opp_table(struct device *dev)
unsigned long freq = be32_to_cpup(val++) * 1000;
unsigned long volt = be32_to_cpup(val++);
- if (dev_pm_opp_add(dev, freq, volt)) {
+ if (dev_pm_opp_add(dev, freq, volt))
dev_warn(dev, "%s: Failed to add OPP %ld\n",
__func__, freq);
- continue;
- }
nr -= 2;
}