Later commits would add support for new OPP bindings and this would be required then. So, lets do it in a separate patch to make it reviewing easy.
Another change worth noticing is INIT_LIST_HEAD(&opp->node). We weren't doing it earlier as we never tried to delete a list node before it is added to list. But this wouldn't be the case anymore. We might try to delete a node (just to reuse the same code paths), without it being getting added to the list.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/base/power/opp.c | 127 ++++++++++++++++++++++++++++------------------- 1 file changed, 75 insertions(+), 52 deletions(-)
diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 9e2118284f02..904dcf386747 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -433,6 +433,7 @@ static void _kfree_device_rcu(struct rcu_head *head) * _opp_remove() - Remove an OPP from a table definition * @dev_opp: points back to the device_opp struct this opp belongs to * @opp: pointer to the OPP to remove + * @notify: OPP_EVENT_REMOVE notification should be sent or not * * This function removes an opp definition from the opp list. * @@ -441,13 +442,14 @@ static void _kfree_device_rcu(struct rcu_head *head) * strategy. */ static void _opp_remove(struct device_opp *dev_opp, - struct dev_pm_opp *opp) + struct dev_pm_opp *opp, bool notify) { /* * Notify the changes in the availability of the operable * frequency/voltage list. */ - srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_REMOVE, opp); + if (notify) + srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_REMOVE, opp); list_del_rcu(&opp->node); call_srcu(&dev_opp->srcu_head.srcu, &opp->rcu_head, _kfree_opp_rcu);
@@ -497,7 +499,7 @@ void dev_pm_opp_remove(struct device *dev, unsigned long freq) goto unlock; }
- _opp_remove(dev_opp, opp); + _opp_remove(dev_opp, opp, true); unlock: mutex_unlock(&dev_opp_list_lock); } @@ -533,6 +535,63 @@ static struct device_opp *_add_device_opp(struct device *dev) return dev_opp; }
+static struct dev_pm_opp *_allocate_opp(struct device *dev, + struct device_opp **dev_opp) +{ + struct dev_pm_opp *opp; + + /* allocate new OPP node */ + opp = kzalloc(sizeof(*opp), GFP_KERNEL); + if (!opp) + return NULL; + + INIT_LIST_HEAD(&opp->node); + + /* Check for existing list for 'dev' */ + *dev_opp = _find_device_opp(dev); + if (IS_ERR(*dev_opp)) { + *dev_opp = _add_device_opp(dev); + if (!*dev_opp) { + kfree(opp); + return NULL; + } + } + + return opp; +} + +static int _opp_add(struct dev_pm_opp *new_opp, struct device_opp *dev_opp) +{ + struct dev_pm_opp *opp = NULL; + struct list_head *head = &dev_opp->opp_list; + + /* + * Insert new OPP in order of increasing frequency + * and discard if already present + */ + list_for_each_entry_rcu(opp, &dev_opp->opp_list, node) { + if (new_opp->rate <= opp->rate) + break; + + head = &opp->node; + } + + /* Duplicate OPPs ? */ + if (opp && new_opp->rate == opp->rate) { + dev_warn(dev_opp->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); + return opp->available && new_opp->u_volt == opp->u_volt ? + 0 : -EEXIST; + } + + new_opp->dev_opp = dev_opp; + list_add_rcu(&new_opp->node, head); + + return 0; +} + /** * _opp_add_dynamic() - Allocate a dynamic OPP. * @dev: device for which we do this operation @@ -563,66 +622,29 @@ static struct device_opp *_add_device_opp(struct device *dev) static int _opp_add_dynamic(struct device *dev, unsigned long freq, long u_volt, bool dynamic) { - struct device_opp *dev_opp = NULL; - struct dev_pm_opp *opp, *new_opp; - struct list_head *head; + struct device_opp *dev_opp; + struct dev_pm_opp *new_opp; int ret;
- /* allocate new OPP node */ - new_opp = kzalloc(sizeof(*new_opp), GFP_KERNEL); - if (!new_opp) { - dev_warn(dev, "%s: Unable to create new OPP node\n", __func__); - return -ENOMEM; - } - /* Hold our list modification lock here */ mutex_lock(&dev_opp_list_lock);
+ new_opp = _allocate_opp(dev, &dev_opp); + if (!new_opp) { + ret = -ENOMEM; + goto unlock; + } + /* populate the opp table */ new_opp->rate = freq; new_opp->u_volt = u_volt; new_opp->available = true; new_opp->dynamic = dynamic;
- /* Check for existing list for 'dev' */ - dev_opp = _find_device_opp(dev); - if (IS_ERR(dev_opp)) { - dev_opp = _add_device_opp(dev); - if (!dev_opp) { - ret = -ENOMEM; - goto free_opp; - } - - head = &dev_opp->opp_list; - goto list_add; - } - - /* - * 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) - break; - else - head = &opp->node; - } - - /* Duplicate OPPs ? */ - if (new_opp->rate == opp->rate) { - 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); + ret = _opp_add(new_opp, dev_opp); + if (ret) goto free_opp; - }
-list_add: - new_opp->dev_opp = dev_opp; - list_add_rcu(&new_opp->node, head); mutex_unlock(&dev_opp_list_lock);
/* @@ -633,8 +655,9 @@ static int _opp_add_dynamic(struct device *dev, unsigned long freq, return 0;
free_opp: + _opp_remove(dev_opp, new_opp, false); +unlock: mutex_unlock(&dev_opp_list_lock); - kfree(new_opp); return ret; }
@@ -922,7 +945,7 @@ void of_free_opp_table(struct device *dev) /* Free static OPPs */ list_for_each_entry_safe(opp, tmp, &dev_opp->opp_list, node) { if (!opp->dynamic) - _opp_remove(dev_opp, opp); + _opp_remove(dev_opp, opp, true); }
mutex_unlock(&dev_opp_list_lock);