diff options
Diffstat (limited to 'drivers/base/power/opp.c')
| -rw-r--r-- | drivers/base/power/opp.c | 44 |
1 files changed, 31 insertions, 13 deletions
diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index d9468642fc4..50b2831e027 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -23,6 +23,7 @@ #include <linux/rcupdate.h> #include <linux/opp.h> #include <linux/of.h> +#include <linux/export.h> /* * Internal data structure organization with the OPP layer library is as @@ -65,6 +66,7 @@ struct opp { unsigned long u_volt; struct device_opp *dev_opp; + struct rcu_head head; }; /** @@ -160,6 +162,7 @@ unsigned long opp_get_voltage(struct opp *opp) return v; } +EXPORT_SYMBOL(opp_get_voltage); /** * opp_get_freq() - Gets the frequency corresponding to an available opp @@ -189,6 +192,7 @@ unsigned long opp_get_freq(struct opp *opp) return f; } +EXPORT_SYMBOL(opp_get_freq); /** * opp_get_opp_count() - Get number of opps available in the opp list @@ -221,6 +225,7 @@ int opp_get_opp_count(struct device *dev) return count; } +EXPORT_SYMBOL(opp_get_opp_count); /** * opp_find_freq_exact() - search for an exact frequency @@ -230,7 +235,10 @@ int opp_get_opp_count(struct device *dev) * * Searches for exact match in the opp list and returns pointer to the matching * opp if found, else returns ERR_PTR in case of error and should be handled - * using IS_ERR. + * using IS_ERR. Error return values can be: + * EINVAL: for bad pointer + * ERANGE: no match found for search + * ENODEV: if device not found in list of registered devices * * Note: available is a modifier for the search. if available=true, then the * match is for exact matching frequency and is available in the stored OPP @@ -249,7 +257,7 @@ struct opp *opp_find_freq_exact(struct device *dev, unsigned long freq, bool available) { struct device_opp *dev_opp; - struct opp *temp_opp, *opp = ERR_PTR(-ENODEV); + struct opp *temp_opp, *opp = ERR_PTR(-ERANGE); dev_opp = find_device_opp(dev); if (IS_ERR(dev_opp)) { @@ -268,6 +276,7 @@ struct opp *opp_find_freq_exact(struct device *dev, unsigned long freq, return opp; } +EXPORT_SYMBOL(opp_find_freq_exact); /** * opp_find_freq_ceil() - Search for an rounded ceil freq @@ -278,7 +287,11 @@ struct opp *opp_find_freq_exact(struct device *dev, unsigned long freq, * for a device. * * Returns matching *opp and refreshes *freq accordingly, else returns - * ERR_PTR in case of error and should be handled using IS_ERR. + * ERR_PTR in case of error and should be handled using IS_ERR. Error return + * values can be: + * EINVAL: for bad pointer + * ERANGE: no match found for search + * ENODEV: if device not found in list of registered devices * * Locking: This function must be called under rcu_read_lock(). opp is a rcu * protected pointer. The reason for the same is that the opp pointer which is @@ -289,7 +302,7 @@ struct opp *opp_find_freq_exact(struct device *dev, unsigned long freq, struct opp *opp_find_freq_ceil(struct device *dev, unsigned long *freq) { struct device_opp *dev_opp; - struct opp *temp_opp, *opp = ERR_PTR(-ENODEV); + struct opp *temp_opp, *opp = ERR_PTR(-ERANGE); if (!dev || !freq) { dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); @@ -298,7 +311,7 @@ struct opp *opp_find_freq_ceil(struct device *dev, unsigned long *freq) dev_opp = find_device_opp(dev); if (IS_ERR(dev_opp)) - return opp; + return ERR_CAST(dev_opp); list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) { if (temp_opp->available && temp_opp->rate >= *freq) { @@ -310,6 +323,7 @@ struct opp *opp_find_freq_ceil(struct device *dev, unsigned long *freq) return opp; } +EXPORT_SYMBOL(opp_find_freq_ceil); /** * opp_find_freq_floor() - Search for a rounded floor freq @@ -320,7 +334,11 @@ struct opp *opp_find_freq_ceil(struct device *dev, unsigned long *freq) * for a device. * * Returns matching *opp and refreshes *freq accordingly, else returns - * ERR_PTR in case of error and should be handled using IS_ERR. + * ERR_PTR in case of error and should be handled using IS_ERR. Error return + * values can be: + * EINVAL: for bad pointer + * ERANGE: no match found for search + * ENODEV: if device not found in list of registered devices * * Locking: This function must be called under rcu_read_lock(). opp is a rcu * protected pointer. The reason for the same is that the opp pointer which is @@ -331,7 +349,7 @@ struct opp *opp_find_freq_ceil(struct device *dev, unsigned long *freq) struct opp *opp_find_freq_floor(struct device *dev, unsigned long *freq) { struct device_opp *dev_opp; - struct opp *temp_opp, *opp = ERR_PTR(-ENODEV); + struct opp *temp_opp, *opp = ERR_PTR(-ERANGE); if (!dev || !freq) { dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); @@ -340,7 +358,7 @@ struct opp *opp_find_freq_floor(struct device *dev, unsigned long *freq) dev_opp = find_device_opp(dev); if (IS_ERR(dev_opp)) - return opp; + return ERR_CAST(dev_opp); list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) { if (temp_opp->available) { @@ -356,6 +374,7 @@ struct opp *opp_find_freq_floor(struct device *dev, unsigned long *freq) return opp; } +EXPORT_SYMBOL(opp_find_freq_floor); /** * opp_add() - Add an OPP table from a table definitions @@ -512,7 +531,7 @@ static int opp_set_availability(struct device *dev, unsigned long freq, list_replace_rcu(&opp->node, &new_opp->node); mutex_unlock(&dev_opp_list_lock); - synchronize_rcu(); + kfree_rcu(opp, head); /* Notify the change of the OPP availability */ if (availability_req) @@ -522,13 +541,10 @@ static int opp_set_availability(struct device *dev, unsigned long freq, srcu_notifier_call_chain(&dev_opp->head, OPP_EVENT_DISABLE, new_opp); - /* clean up old opp */ - new_opp = opp; - goto out; + return 0; unlock: mutex_unlock(&dev_opp_list_lock); -out: kfree(new_opp); return r; } @@ -552,6 +568,7 @@ int opp_enable(struct device *dev, unsigned long freq) { return opp_set_availability(dev, freq, true); } +EXPORT_SYMBOL(opp_enable); /** * opp_disable() - Disable a specific OPP @@ -573,6 +590,7 @@ int opp_disable(struct device *dev, unsigned long freq) { return opp_set_availability(dev, freq, false); } +EXPORT_SYMBOL(opp_disable); #ifdef CONFIG_CPU_FREQ /** |