OPP bindings (for few properties) allow a platform to choose a value/range among a set of available options. The options are present as opp-<prop>-<name>, where the platform needs to supply the <name> string.
The OPP properties which allow such an option are: opp-microvolt and opp-microamp.
Add support to the OPP-core to parse these bindings, by introducing dev_pm_opp_{set|put}_prop_name() APIs.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/base/power/opp/core.c | 165 ++++++++++++++++++++++++++++++++++++++---- drivers/base/power/opp/opp.h | 2 + include/linux/pm_opp.h | 9 +++ 3 files changed, 161 insertions(+), 15 deletions(-)
diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index 55cf1a99b532..5c01fec1ed14 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -562,6 +562,9 @@ static void _remove_device_opp(struct device_opp *dev_opp) if (dev_opp->supported_hw) return;
+ if (dev_opp->prop_name) + return; + list_dev = list_first_entry(&dev_opp->dev_list, struct device_list_opp, node);
@@ -794,35 +797,48 @@ static int _opp_add_v1(struct device *dev, unsigned long freq, long u_volt, }
/* TODO: Support multiple regulators */ -static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev) +static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev, + struct device_opp *dev_opp) { u32 microvolt[3] = {0}; u32 val; int count, ret; + struct property *prop = NULL; + char name[NAME_MAX]; + + /* Search for "opp-microvolt-<name>" */ + if (dev_opp->prop_name) { + sprintf(name, "opp-microvolt-%s", dev_opp->prop_name); + prop = of_find_property(opp->np, name, NULL); + } + + if (!prop) { + /* Search for "opp-microvolt" */ + name[13] = '\0'; + prop = of_find_property(opp->np, name, NULL);
- /* Missing property isn't a problem, but an invalid entry is */ - if (!of_find_property(opp->np, "opp-microvolt", NULL)) - return 0; + /* Missing property isn't a problem, but an invalid entry is */ + if (!prop) + return 0; + }
- count = of_property_count_u32_elems(opp->np, "opp-microvolt"); + count = of_property_count_u32_elems(opp->np, name); if (count < 0) { - dev_err(dev, "%s: Invalid opp-microvolt property (%d)\n", - __func__, count); + dev_err(dev, "%s: Invalid %s property (%d)\n", + __func__, name, count); return count; }
/* There can be one or three elements here */ if (count != 1 && count != 3) { - dev_err(dev, "%s: Invalid number of elements in opp-microvolt property (%d)\n", - __func__, count); + dev_err(dev, "%s: Invalid number of elements in %s property (%d)\n", + __func__, name, count); return -EINVAL; }
- ret = of_property_read_u32_array(opp->np, "opp-microvolt", microvolt, - count); + ret = of_property_read_u32_array(opp->np, name, microvolt, count); if (ret) { - dev_err(dev, "%s: error parsing opp-microvolt: %d\n", __func__, - ret); + dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret); return -EINVAL; }
@@ -830,7 +846,20 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev) opp->u_volt_min = microvolt[1]; opp->u_volt_max = microvolt[2];
- if (!of_property_read_u32(opp->np, "opp-microamp", &val)) + /* Search for "opp-microamp-<name>" */ + prop = NULL; + if (dev_opp->prop_name) { + sprintf(name, "opp-microamp-%s", dev_opp->prop_name); + prop = of_find_property(opp->np, name, NULL); + } + + if (!prop) { + /* Search for "opp-microamp" */ + name[12] = '\0'; + prop = of_find_property(opp->np, name, NULL); + } + + if (prop && !of_property_read_u32(opp->np, name, &val)) opp->u_amp = val;
return 0; @@ -948,6 +977,112 @@ void dev_pm_opp_put_supported_hw(struct device *dev) } EXPORT_SYMBOL_GPL(dev_pm_opp_put_supported_hw);
+/** + * dev_pm_opp_set_prop_name() - Set prop-extn name + * @dev: Device for which the regulator has to be set. + * @name: name to postfix to properties. + * + * This is required only for the V2 bindings, and it enables a platform to + * specify the extn to be used for certain property names. The properties to + * which the extension will apply are opp-microvolt and opp-microamp. OPP core + * should postfix the property name with -<name> while looking for them. + * + * 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_prop_name(struct device *dev, const char *name) +{ + 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 prop-name associated with dev_opp? */ + if (dev_opp->prop_name) { + dev_err(dev, "%s: Already have prop-name %s\n", __func__, + dev_opp->prop_name); + ret = -EBUSY; + goto err; + } + + dev_opp->prop_name = kstrdup(name, GFP_KERNEL); + if (!dev_opp->prop_name) { + ret = -ENOMEM; + goto err; + } + + 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_prop_name); + +/** + * dev_pm_opp_put_prop_name() - Releases resources blocked for prop-name + * @dev: Device for which the regulator has to be set. + * + * This is required only for the V2 bindings, and is called for a matching + * dev_pm_opp_set_prop_name(). 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_prop_name(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->prop_name) { + dev_err(dev, "%s: Doesn't have a prop-name\n", __func__); + goto unlock; + } + + kfree(dev_opp->prop_name); + dev_opp->prop_name = NULL; + + /* 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_prop_name); + static bool _opp_is_supported(struct device *dev, struct device_opp *dev_opp, struct device_node *np) { @@ -1042,7 +1177,7 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np) if (!of_property_read_u32(np, "clock-latency-ns", &val)) new_opp->clock_latency_ns = val;
- ret = opp_parse_supplies(new_opp, dev); + ret = opp_parse_supplies(new_opp, dev, dev_opp); if (ret) goto free_opp;
diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h index 70f4564a6ab9..690638ef36ee 100644 --- a/drivers/base/power/opp/opp.h +++ b/drivers/base/power/opp/opp.h @@ -131,6 +131,7 @@ struct device_list_opp { * @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. + * @prop_name: A name to postfix to many DT properties, while parsing them. * @dentry: debugfs dentry pointer of the real device directory (not links). * @dentry_name: Name of the real dentry. * @@ -157,6 +158,7 @@ struct device_opp {
unsigned int *supported_hw; unsigned int supported_hw_count; + const char *prop_name;
#ifdef CONFIG_DEBUG_FS struct dentry *dentry; diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index 3a85110242f0..95403d2ccaf5 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -58,6 +58,8 @@ 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); +int dev_pm_opp_set_prop_name(struct device *dev, const char *name); +void dev_pm_opp_put_prop_name(struct device *dev); #else static inline unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp) { @@ -142,6 +144,13 @@ static inline int dev_pm_opp_set_supported_hw(struct device *dev,
static inline void dev_pm_opp_put_supported_hw(struct device *dev) {}
+static inline int dev_pm_opp_set_prop_name(struct device *dev, const char *name) +{ + return -EINVAL; +} + +static inline void dev_pm_opp_put_prop_name(struct device *dev) {} + #endif /* CONFIG_PM_OPP */
#if defined(CONFIG_PM_OPP) && defined(CONFIG_OF)