On 9 December 2015 at 02:31, Viresh Kumar viresh.kumar@linaro.org wrote:
OPP bindings allow a platform to enable OPPs based on the version of the hardware they are used for.
Add support to the OPP-core to parse these bindings, by introducing dev_pm_opp_{set|put}_supported_hw() APIs.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
drivers/base/power/opp/core.c | 148 ++++++++++++++++++++++++++++++++++++++++++ drivers/base/power/opp/opp.h | 5 ++ include/linux/pm_opp.h | 13 ++++ 3 files changed, 166 insertions(+)
Tested-by: Lee Jones lee.jones@linaro.org
diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index 6aa172be6e8e..55cf1a99b532 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -559,6 +559,9 @@ static void _remove_device_opp(struct device_opp *dev_opp) if (!list_empty(&dev_opp->opp_list)) return;
if (dev_opp->supported_hw)
return;
list_dev = list_first_entry(&dev_opp->dev_list, struct device_list_opp, node);
@@ -834,6 +837,145 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev) }
/**
- dev_pm_opp_set_supported_hw() - Set supported platforms
- @dev: Device for which supported-hw has to be set.
- @versions: Array of hierarchy of versions to match.
- @count: Number of elements in the array.
- This is required only for the V2 bindings, and it enables a platform to
- specify the hierarchy of versions it supports. OPP layer will then enable
- OPPs, which are available for those versions, based on its 'opp-supported-hw'
- property.
- Locking: The internal device_opp and opp structures are RCU protected.
- Hence this function internally uses RCU updater strategy with mutex locks
- 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.
- */
+int dev_pm_opp_set_supported_hw(struct device *dev, const u32 *versions,
unsigned int count)
+{
struct device_opp *dev_opp;
int ret = 0;
/* Hold our list modification lock here */
mutex_lock(&dev_opp_list_lock);
dev_opp = _add_device_opp(dev);
if (!dev_opp) {
ret = -ENOMEM;
goto unlock;
}
/* Make sure there are no concurrent readers while updating dev_opp */
WARN_ON(!list_empty(&dev_opp->opp_list));
/* Do we already have a version hierarchy associated with dev_opp? */
if (dev_opp->supported_hw) {
dev_err(dev, "%s: Already have supported hardware list\n",
__func__);
ret = -EBUSY;
goto err;
}
dev_opp->supported_hw = kmemdup(versions, count * sizeof(*versions),
GFP_KERNEL);
if (!dev_opp->supported_hw) {
ret = -ENOMEM;
goto err;
}
dev_opp->supported_hw_count = count;
mutex_unlock(&dev_opp_list_lock);
return 0;
+err:
_remove_device_opp(dev_opp);
+unlock:
mutex_unlock(&dev_opp_list_lock);
return ret;
+} +EXPORT_SYMBOL_GPL(dev_pm_opp_set_supported_hw);
+/**
- dev_pm_opp_put_supported_hw() - Releases resources blocked for supported hw
- @dev: Device for which supported-hw has to be set.
- This is required only for the V2 bindings, and is called for a matching
- dev_pm_opp_set_supported_hw(). Until this is called, the device_opp structure
- will not be freed.
- Locking: The internal device_opp and opp structures are RCU protected.
- Hence this function internally uses RCU updater strategy with mutex locks
- 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.
- */
+void dev_pm_opp_put_supported_hw(struct device *dev) +{
struct device_opp *dev_opp;
/* Hold our list modification lock here */
mutex_lock(&dev_opp_list_lock);
/* Check for existing list for 'dev' first */
dev_opp = _find_device_opp(dev);
if (IS_ERR(dev_opp)) {
dev_err(dev, "Failed to find dev_opp: %ld\n", PTR_ERR(dev_opp));
goto unlock;
}
/* Make sure there are no concurrent readers while updating dev_opp */
WARN_ON(!list_empty(&dev_opp->opp_list));
if (!dev_opp->supported_hw) {
dev_err(dev, "%s: Doesn't have supported hardware list\n",
__func__);
goto unlock;
}
kfree(dev_opp->supported_hw);
dev_opp->supported_hw = NULL;
dev_opp->supported_hw_count = 0;
/* Try freeing device_opp if this was the last blocking resource */
_remove_device_opp(dev_opp);
+unlock:
mutex_unlock(&dev_opp_list_lock);
+} +EXPORT_SYMBOL_GPL(dev_pm_opp_put_supported_hw);
+static bool _opp_is_supported(struct device *dev, struct device_opp *dev_opp,
struct device_node *np)
+{
unsigned int count = dev_opp->supported_hw_count;
u32 version;
int ret;
if (!dev_opp->supported_hw)
return true;
while (count--) {
ret = of_property_read_u32_index(np, "opp-supported-hw", count,
&version);
if (ret) {
dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
__func__, count, ret);
return false;
}
/* Both of these are bitwise masks of the versions */
if (!(version & dev_opp->supported_hw[count]))
return false;
}
return true;
+}
+/**
- _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
- @dev: device for which we do this operation
- @np: device node
@@ -879,6 +1021,12 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np) goto free_opp; }
/* Check if the OPP supports hardware's hierarchy of versions or not */
if (!_opp_is_supported(dev, dev_opp, np)) {
dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
goto free_opp;
}
/* * Rate is defined as an unsigned long in clk API, and so casting * explicitly to its type. Must be fixed once rate is 64 bit
diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h index b8880c7f8be1..70f4564a6ab9 100644 --- a/drivers/base/power/opp/opp.h +++ b/drivers/base/power/opp/opp.h @@ -129,6 +129,8 @@ struct device_list_opp {
- @clock_latency_ns_max: Max clock latency in nanoseconds.
- @shared_opp: OPP is shared between multiple devices.
- @suspend_opp: Pointer to OPP to be used during device suspend.
- @supported_hw: Array of version number to support.
- @supported_hw_count: Number of elements in supported_hw array.
- @dentry: debugfs dentry pointer of the real device directory (not links).
- @dentry_name: Name of the real dentry.
@@ -153,6 +155,9 @@ struct device_opp { bool shared_opp; struct dev_pm_opp *suspend_opp;
unsigned int *supported_hw;
unsigned int supported_hw_count;
#ifdef CONFIG_DEBUG_FS struct dentry *dentry; char dentry_name[NAME_MAX]; diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index 9a2e50337af9..3a85110242f0 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -55,6 +55,9 @@ int dev_pm_opp_enable(struct device *dev, unsigned long freq); int dev_pm_opp_disable(struct device *dev, unsigned long freq);
struct srcu_notifier_head *dev_pm_opp_get_notifier(struct device *dev); +int dev_pm_opp_set_supported_hw(struct device *dev, const u32 *versions,
unsigned int count);
+void dev_pm_opp_put_supported_hw(struct device *dev); #else static inline unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp) { @@ -129,6 +132,16 @@ static inline struct srcu_notifier_head *dev_pm_opp_get_notifier( { return ERR_PTR(-EINVAL); }
+static inline int dev_pm_opp_set_supported_hw(struct device *dev,
const u32 *versions,
unsigned int count)
+{
return -EINVAL;
+}
+static inline void dev_pm_opp_put_supported_hw(struct device *dev) {}
#endif /* CONFIG_PM_OPP */
#if defined(CONFIG_PM_OPP) && defined(CONFIG_OF)
2.6.2.198.g614a2ac
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