From 7ad68e2f970fd84d15ad67ce3216aed05f944a9c Mon Sep 17 00:00:00 2001 From: David Brownell Date: Tue, 11 Nov 2008 17:39:02 -0800 Subject: [PATCH] regulator: sysfs attribute reduction (v2) Clean up the sysfs interface to regulators by only exposing the attributes that can be properly displayed. For example: when a particular regulator method is needed to display the value, only create that attribute when that method exists. This cleaned-up interface is much more comprehensible. Most regulators only support a subset of the possible methods, so often more than half the attributes would be meaningless. Many "not defined" values are no longer necessary. (But handling of out-of-range values still looks a bit iffy.) Documentation is updated to reflect that few of the attributes are *always* present, and to briefly explain why a regulator may not have a given attribute. This adds object code, about a dozen bytes more than was removed by the preceding patch, but saves a bunch of per-regulator data associated with the now-removed attributes. So there's a net reduction in memory footprint. Signed-off-by: David Brownell Signed-off-by: Liam Girdwood --- Documentation/ABI/testing/sysfs-class-regulator | 136 ++++++++-------- drivers/regulator/core.c | 196 ++++++++++++++++++------ 2 files changed, 208 insertions(+), 124 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-class-regulator b/Documentation/ABI/testing/sysfs-class-regulator index 3731f6f..873ef1f 100644 --- a/Documentation/ABI/testing/sysfs-class-regulator +++ b/Documentation/ABI/testing/sysfs-class-regulator @@ -3,8 +3,9 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called - state. This holds the regulator output state. + Some regulator directories will contain a field called + state. This reports the regulator enable status, for + regulators which can report that value. This will be one of the following strings: @@ -18,7 +19,8 @@ Description: 'disabled' means the regulator output is OFF and is not supplying power to the system.. - 'unknown' means software cannot determine the state. + 'unknown' means software cannot determine the state, or + the reported state is invalid. NOTE: this field can be used in conjunction with microvolts and microamps to determine regulator output levels. @@ -53,9 +55,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called microvolts. This holds the regulator output voltage setting - measured in microvolts (i.e. E-6 Volts). + measured in microvolts (i.e. E-6 Volts), for regulators + which can report that voltage. NOTE: This value should not be used to determine the regulator output voltage level as this value is the same regardless of @@ -67,9 +70,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called microamps. This holds the regulator output current limit - setting measured in microamps (i.e. E-6 Amps). + setting measured in microamps (i.e. E-6 Amps), for regulators + which can report that current. NOTE: This value should not be used to determine the regulator output current level as this value is the same regardless of @@ -81,8 +85,9 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called - opmode. This holds the regulator operating mode setting. + Some regulator directories will contain a field called + opmode. This holds the current regulator operating mode, + for regulators which can report it. The opmode value can be one of the following strings: @@ -92,7 +97,7 @@ Description: 'standby' 'unknown' - The modes are described in include/linux/regulator/regulator.h + The modes are described in include/linux/regulator/consumer.h NOTE: This value should not be used to determine the regulator output operating mode as this value is the same regardless of @@ -104,9 +109,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called min_microvolts. This holds the minimum safe working regulator - output voltage setting for this domain measured in microvolts. + output voltage setting for this domain measured in microvolts, + for regulators which support voltage constraints. NOTE: this will return the string 'constraint not defined' if the power domain has no min microvolts constraint defined by @@ -118,9 +124,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called max_microvolts. This holds the maximum safe working regulator - output voltage setting for this domain measured in microvolts. + output voltage setting for this domain measured in microvolts, + for regulators which support voltage constraints. NOTE: this will return the string 'constraint not defined' if the power domain has no max microvolts constraint defined by @@ -132,10 +139,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called min_microamps. This holds the minimum safe working regulator output current limit setting for this domain measured in - microamps. + microamps, for regulators which support current constraints. NOTE: this will return the string 'constraint not defined' if the power domain has no min microamps constraint defined by @@ -147,10 +154,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called max_microamps. This holds the maximum safe working regulator output current limit setting for this domain measured in - microamps. + microamps, for regulators which support current constraints. NOTE: this will return the string 'constraint not defined' if the power domain has no max microamps constraint defined by @@ -185,7 +192,7 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called requested_microamps. This holds the total requested load current in microamps for this regulator from all its consumer devices. @@ -204,125 +211,102 @@ Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_mem_microvolts. This holds the regulator output voltage setting for this domain measured in microvolts when - the system is suspended to memory. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to memory voltage defined by - platform code. + the system is suspended to memory, for voltage regulators + implementing suspend voltage configuration constraints. What: /sys/class/regulator/.../suspend_disk_microvolts Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_disk_microvolts. This holds the regulator output voltage setting for this domain measured in microvolts when - the system is suspended to disk. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to disk voltage defined by - platform code. + the system is suspended to disk, for voltage regulators + implementing suspend voltage configuration constraints. What: /sys/class/regulator/.../suspend_standby_microvolts Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_standby_microvolts. This holds the regulator output voltage setting for this domain measured in microvolts when - the system is suspended to standby. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to standby voltage defined by - platform code. + the system is suspended to standby, for voltage regulators + implementing suspend voltage configuration constraints. What: /sys/class/regulator/.../suspend_mem_mode Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_mem_mode. This holds the regulator operating mode setting for this domain when the system is suspended to - memory. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to memory mode defined by - platform code. + memory, for regulators implementing suspend mode + configuration constraints. What: /sys/class/regulator/.../suspend_disk_mode Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_disk_mode. This holds the regulator operating mode - setting for this domain when the system is suspended to disk. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to disk mode defined by - platform code. + setting for this domain when the system is suspended to disk, + for regulators implementing suspend mode configuration + constraints. What: /sys/class/regulator/.../suspend_standby_mode Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_standby_mode. This holds the regulator operating mode setting for this domain when the system is suspended to - standby. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to standby mode defined by - platform code. + standby, for regulators implementing suspend mode + configuration constraints. What: /sys/class/regulator/.../suspend_mem_state Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_mem_state. This holds the regulator operating state - when suspended to memory. - - This will be one of the following strings: + when suspended to memory, for regulators implementing suspend + configuration constraints. - 'enabled' - 'disabled' - 'not defined' + This will be one of the same strings reported by + the "state" attribute. What: /sys/class/regulator/.../suspend_disk_state Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_disk_state. This holds the regulator operating state - when suspended to disk. - - This will be one of the following strings: + when suspended to disk, for regulators implementing + suspend configuration constraints. - 'enabled' - 'disabled' - 'not defined' + This will be one of the same strings reported by + the "state" attribute. What: /sys/class/regulator/.../suspend_standby_state Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_standby_state. This holds the regulator operating - state when suspended to standby. - - This will be one of the following strings: + state when suspended to standby, for regulators implementing + suspend configuration constraints. - 'enabled' - 'disabled' - 'not defined' + This will be one of the same strings reported by + the "state" attribute. diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 5109f7d..9a5ff97 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -242,6 +242,7 @@ static ssize_t regulator_uV_show(struct device *dev, return ret; } +static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL); static ssize_t regulator_uA_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -250,6 +251,7 @@ static ssize_t regulator_uA_show(struct device *dev, return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev)); } +static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL); static ssize_t regulator_name_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -289,6 +291,7 @@ static ssize_t regulator_opmode_show(struct device *dev, return regulator_print_opmode(buf, _regulator_get_mode(rdev)); } +static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL); static ssize_t regulator_print_state(char *buf, int state) { @@ -307,6 +310,7 @@ static ssize_t regulator_state_show(struct device *dev, return regulator_print_state(buf, _regulator_is_enabled(rdev)); } +static DEVICE_ATTR(state, 0444, regulator_state_show, NULL); static ssize_t regulator_min_uA_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -318,6 +322,7 @@ static ssize_t regulator_min_uA_show(struct device *dev, return sprintf(buf, "%d\n", rdev->constraints->min_uA); } +static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL); static ssize_t regulator_max_uA_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -329,6 +334,7 @@ static ssize_t regulator_max_uA_show(struct device *dev, return sprintf(buf, "%d\n", rdev->constraints->max_uA); } +static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL); static ssize_t regulator_min_uV_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -340,6 +346,7 @@ static ssize_t regulator_min_uV_show(struct device *dev, return sprintf(buf, "%d\n", rdev->constraints->min_uV); } +static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL); static ssize_t regulator_max_uV_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -351,6 +358,7 @@ static ssize_t regulator_max_uV_show(struct device *dev, return sprintf(buf, "%d\n", rdev->constraints->max_uV); } +static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL); static ssize_t regulator_total_uA_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -365,6 +373,7 @@ static ssize_t regulator_total_uA_show(struct device *dev, mutex_unlock(&rdev->mutex); return sprintf(buf, "%d\n", uA); } +static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL); static ssize_t regulator_num_users_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -392,131 +401,106 @@ static ssize_t regulator_suspend_mem_uV_show(struct device *dev, { struct regulator_dev *rdev = dev_get_drvdata(dev); - if (!rdev->constraints) - return sprintf(buf, "not defined\n"); return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV); } +static DEVICE_ATTR(suspend_mem_microvolts, 0444, + regulator_suspend_mem_uV_show, NULL); static ssize_t regulator_suspend_disk_uV_show(struct device *dev, struct device_attribute *attr, char *buf) { struct regulator_dev *rdev = dev_get_drvdata(dev); - if (!rdev->constraints) - return sprintf(buf, "not defined\n"); return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV); } +static DEVICE_ATTR(suspend_disk_microvolts, 0444, + regulator_suspend_disk_uV_show, NULL); static ssize_t regulator_suspend_standby_uV_show(struct device *dev, struct device_attribute *attr, char *buf) { struct regulator_dev *rdev = dev_get_drvdata(dev); - if (!rdev->constraints) - return sprintf(buf, "not defined\n"); return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV); } +static DEVICE_ATTR(suspend_standby_microvolts, 0444, + regulator_suspend_standby_uV_show, NULL); static ssize_t regulator_suspend_mem_mode_show(struct device *dev, struct device_attribute *attr, char *buf) { struct regulator_dev *rdev = dev_get_drvdata(dev); - if (!rdev->constraints) - return sprintf(buf, "not defined\n"); return regulator_print_opmode(buf, rdev->constraints->state_mem.mode); } +static DEVICE_ATTR(suspend_mem_mode, 0444, + regulator_suspend_mem_mode_show, NULL); static ssize_t regulator_suspend_disk_mode_show(struct device *dev, struct device_attribute *attr, char *buf) { struct regulator_dev *rdev = dev_get_drvdata(dev); - if (!rdev->constraints) - return sprintf(buf, "not defined\n"); return regulator_print_opmode(buf, rdev->constraints->state_disk.mode); } +static DEVICE_ATTR(suspend_disk_mode, 0444, + regulator_suspend_disk_mode_show, NULL); static ssize_t regulator_suspend_standby_mode_show(struct device *dev, struct device_attribute *attr, char *buf) { struct regulator_dev *rdev = dev_get_drvdata(dev); - if (!rdev->constraints) - return sprintf(buf, "not defined\n"); return regulator_print_opmode(buf, rdev->constraints->state_standby.mode); } +static DEVICE_ATTR(suspend_standby_mode, 0444, + regulator_suspend_standby_mode_show, NULL); static ssize_t regulator_suspend_mem_state_show(struct device *dev, struct device_attribute *attr, char *buf) { struct regulator_dev *rdev = dev_get_drvdata(dev); - if (!rdev->constraints) - return sprintf(buf, "not defined\n"); - return regulator_print_state(buf, rdev->constraints->state_mem.enabled); } +static DEVICE_ATTR(suspend_mem_state, 0444, + regulator_suspend_mem_state_show, NULL); static ssize_t regulator_suspend_disk_state_show(struct device *dev, struct device_attribute *attr, char *buf) { struct regulator_dev *rdev = dev_get_drvdata(dev); - if (!rdev->constraints) - return sprintf(buf, "not defined\n"); - return regulator_print_state(buf, rdev->constraints->state_disk.enabled); } +static DEVICE_ATTR(suspend_disk_state, 0444, + regulator_suspend_disk_state_show, NULL); static ssize_t regulator_suspend_standby_state_show(struct device *dev, struct device_attribute *attr, char *buf) { struct regulator_dev *rdev = dev_get_drvdata(dev); - if (!rdev->constraints) - return sprintf(buf, "not defined\n"); - return regulator_print_state(buf, rdev->constraints->state_standby.enabled); } +static DEVICE_ATTR(suspend_standby_state, 0444, + regulator_suspend_standby_state_show, NULL); + +/* + * These are the only attributes are present for all regulators. + * Other attributes are a function of regulator functionality. + */ static struct device_attribute regulator_dev_attrs[] = { __ATTR(name, 0444, regulator_name_show, NULL), - __ATTR(microvolts, 0444, regulator_uV_show, NULL), - __ATTR(microamps, 0444, regulator_uA_show, NULL), - __ATTR(opmode, 0444, regulator_opmode_show, NULL), - __ATTR(state, 0444, regulator_state_show, NULL), - __ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL), - __ATTR(min_microamps, 0444, regulator_min_uA_show, NULL), - __ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL), - __ATTR(max_microamps, 0444, regulator_max_uA_show, NULL), - __ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL), __ATTR(num_users, 0444, regulator_num_users_show, NULL), __ATTR(type, 0444, regulator_type_show, NULL), - __ATTR(suspend_mem_microvolts, 0444, - regulator_suspend_mem_uV_show, NULL), - __ATTR(suspend_disk_microvolts, 0444, - regulator_suspend_disk_uV_show, NULL), - __ATTR(suspend_standby_microvolts, 0444, - regulator_suspend_standby_uV_show, NULL), - __ATTR(suspend_mem_mode, 0444, - regulator_suspend_mem_mode_show, NULL), - __ATTR(suspend_disk_mode, 0444, - regulator_suspend_disk_mode_show, NULL), - __ATTR(suspend_standby_mode, 0444, - regulator_suspend_standby_mode_show, NULL), - __ATTR(suspend_mem_state, 0444, - regulator_suspend_mem_state_show, NULL), - __ATTR(suspend_disk_state, 0444, - regulator_suspend_disk_state_show, NULL), - __ATTR(suspend_standby_state, 0444, - regulator_suspend_standby_state_show, NULL), __ATTR_NULL, }; @@ -1711,6 +1695,117 @@ int regulator_notifier_call_chain(struct regulator_dev *rdev, } EXPORT_SYMBOL_GPL(regulator_notifier_call_chain); +/* + * To avoid cluttering sysfs (and memory) with useless state, only + * create attributes that can be meaningfully displayed. + */ +static int add_regulator_attributes(struct regulator_dev *rdev) +{ + struct device *dev = &rdev->dev; + struct regulator_ops *ops = rdev->desc->ops; + int status = 0; + + /* some attributes need specific methods to be displayed */ + if (ops->get_voltage) { + status = device_create_file(dev, &dev_attr_microvolts); + if (status < 0) + return status; + } + if (ops->get_current_limit) { + status = device_create_file(dev, &dev_attr_microamps); + if (status < 0) + return status; + } + if (ops->get_mode) { + status = device_create_file(dev, &dev_attr_opmode); + if (status < 0) + return status; + } + if (ops->is_enabled) { + status = device_create_file(dev, &dev_attr_state); + if (status < 0) + return status; + } + + /* some attributes are type-specific */ + if (rdev->desc->type == REGULATOR_CURRENT) { + status = device_create_file(dev, &dev_attr_requested_microamps); + if (status < 0) + return status; + } + + /* all the other attributes exist to support constraints; + * don't show them if there are no constraints, or if the + * relevant supporting methods are missing. + */ + if (!rdev->constraints) + return status; + + /* constraints need specific supporting methods */ + if (ops->set_voltage) { + status = device_create_file(dev, &dev_attr_min_microvolts); + if (status < 0) + return status; + status = device_create_file(dev, &dev_attr_max_microvolts); + if (status < 0) + return status; + } + if (ops->set_current_limit) { + status = device_create_file(dev, &dev_attr_min_microamps); + if (status < 0) + return status; + status = device_create_file(dev, &dev_attr_max_microamps); + if (status < 0) + return status; + } + + /* suspend mode constraints need multiple supporting methods */ + if (!(ops->set_suspend_enable && ops->set_suspend_disable)) + return status; + + status = device_create_file(dev, &dev_attr_suspend_standby_state); + if (status < 0) + return status; + status = device_create_file(dev, &dev_attr_suspend_mem_state); + if (status < 0) + return status; + status = device_create_file(dev, &dev_attr_suspend_disk_state); + if (status < 0) + return status; + + if (ops->set_suspend_voltage) { + status = device_create_file(dev, + &dev_attr_suspend_standby_microvolts); + if (status < 0) + return status; + status = device_create_file(dev, + &dev_attr_suspend_mem_microvolts); + if (status < 0) + return status; + status = device_create_file(dev, + &dev_attr_suspend_disk_microvolts); + if (status < 0) + return status; + } + + if (ops->set_suspend_mode) { + status = device_create_file(dev, + &dev_attr_suspend_standby_mode); + if (status < 0) + return status; + status = device_create_file(dev, + &dev_attr_suspend_mem_mode); + if (status < 0) + return status; + status = device_create_file(dev, + &dev_attr_suspend_disk_mode); + if (status < 0) + return status; + } + + return status; +} + /** * regulator_register - register regulator * @regulator: regulator source @@ -1779,6 +1874,11 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc, dev_set_drvdata(&rdev->dev, rdev); + /* add attributes supported by this regulator */ + ret = add_regulator_attributes(rdev); + if (ret < 0) + goto scrub; + /* set supply regulator if it exists */ if (init_data->supply_regulator_dev) { ret = set_supply(rdev, -- 2.7.4