Voltage and current regulator API¶
- Author:
Liam Girdwood
- Author:
Mark Brown
Introduction¶
This framework is designed to provide a standard kernel interface tocontrol voltage and current regulators.
The intention is to allow systems to dynamically control regulator poweroutput in order to save power and prolong battery life. This applies toboth voltage regulators (where voltage output is controllable) andcurrent sinks (where current limit is controllable).
Note that additional (and currently more complete) documentation isavailable in the Linux kernel source underDocumentation/power/regulator.
Glossary¶
The regulator API uses a number of terms which may not be familiar:
Regulator
Electronic device that supplies power to other devices. Most regulatorscan enable and disable their output and some can also control theiroutput voltage or current.
Consumer
Electronic device which consumes power provided by a regulator. Thesemay either be static, requiring only a fixed supply, or dynamic,requiring active management of the regulator at runtime.
Power Domain
The electronic circuit supplied by a given regulator, including theregulator and all consumer devices. The configuration of the regulatoris shared between all the components in the circuit.
Power Management Integrated Circuit (PMIC)
An IC which contains numerous regulators and often also othersubsystems. In an embedded system the primary PMIC is often equivalentto a combination of the PSU and southbridge in a desktop system.
Consumer driver interface¶
This offers a similar API to the kernel clock framework. Consumerdrivers useget andput operations to acquire and releaseregulators. Functions are provided toenableanddisable the regulator and to get andset the runtime parameters of the regulator.
When requesting regulators consumers use symbolic names for theirsupplies, such as “Vcc”, which are mapped into actual regulator devicesby the machine interface.
A stub version of this API is provided when the regulator framework isnot in use in order to minimise the need to use ifdefs.
Enabling and disabling¶
The regulator API provides reference counted enabling and disabling ofregulators. Consumer devices use theregulator_enable() andregulator_disable() functions to enable and disableregulators. Calls to the two functions must be balanced.
Note that since multiple consumers may be using a regulator and machineconstraints may not allow the regulator to be disabled there is noguarantee that callingregulator_disable() will actuallycause the supply provided by the regulator to be disabled. Consumerdrivers should assume that the regulator may be enabled at all times.
Configuration¶
Some consumer devices may need to be able to dynamically configure theirsupplies. For example, MMC drivers may need to select the correctoperating voltage for their cards. This may be done while the regulatoris enabled or disabled.
Theregulator_set_voltage() andregulator_set_current_limit() functions provide the primaryinterface for this. Both take ranges of voltages and currents, supportingdrivers that do not require a specific value (eg, CPU frequency scalingnormally permits the CPU to use a wider range of supply voltages at lowerfrequencies but does not require that the supply voltage be lowered). Wherean exact value is required both minimum and maximum values should beidentical.
Callbacks¶
Callbacks may also be registered for events such as regulation failures.
Regulator driver interface¶
Drivers for regulator chips register the regulators with the regulatorcore, providing operations structures to the core. A notifier interfaceallows error conditions to be reported to the core.
Registration should be triggered by explicit setup done by the platform,supplying astructregulator_init_data for the regulatorcontaining constraint and supply information.
Machine interface¶
This interface provides a way to define how regulators are connected toconsumers on a given system and what the valid operating parameters arefor the system.
Supplies¶
Regulator supplies are specified using structregulator_consumer_supply. This is done at driver registrationtime as part of the machine constraints.
Constraints¶
As well as defining the connections the machine interface also providesconstraints defining the operations that clients are allowed to performand the parameters that may be set. This is required since generallyregulator devices will offer more flexibility than it is safe to use ona given system, for example supporting higher supply voltages than theconsumers are rated for.
This is done at driver registration time` by providing astructregulation_constraints.
The constraints may also specify an initial configuration for theregulator in the constraints, which is particularly useful for use withstatic consumers.
API reference¶
Due to limitations of the kernel documentation framework and theexisting layout of the source code the entire regulator API isdocumented here.
- structpre_voltage_change_data¶
Data sent with PRE_VOLTAGE_CHANGE event
Definition:
struct pre_voltage_change_data { unsigned long old_uV; unsigned long min_uV; unsigned long max_uV;};Members
old_uVCurrent voltage before change.
min_uVMin voltage we’ll change to.
max_uVMax voltage we’ll change to.
- structregulator_bulk_data¶
Data used for bulk regulator operations.
Definition:
struct regulator_bulk_data { const char *supply; struct regulator *consumer; int init_load_uA;};Members
supplyThe name of the supply. Initialised by the user beforeusing the bulk regulator APIs.
consumerThe regulator consumer for the supply. This will be managedby the bulk API.
init_load_uAAfter getting the regulator,
regulator_set_load()will becalled with this load. Initialised by the user beforeusing the bulk regulator APIs.
Description
The regulator APIs provide a series ofregulator_bulk_() API calls asa convenience to consumers which require multiple supplies. Thisstructure is used to manage data for these calls.
- structregulator_state¶
regulator state during low power system states
Definition:
struct regulator_state { int uV; int min_uV; int max_uV; unsigned int mode; int enabled; bool changeable;};Members
uVDefault operating voltage during suspend, it can be adjustedamong <min_uV, max_uV>.
min_uVMinimum suspend voltage may be set.
max_uVMaximum suspend voltage may be set.
modeOperating mode during suspend.
enabledoperations during suspend.- DO_NOTHING_IN_SUSPEND- DISABLE_IN_SUSPEND- ENABLE_IN_SUSPEND
changeableIs this state can be switched between enabled/disabled,
Description
This describes a regulators state during a system wide low powerstate. One of enabled or disabled must be set for theconfiguration to be applied.
- structregulation_constraints¶
regulator operating constraints.
Definition:
struct regulation_constraints { const char *name; int min_uV; int max_uV; int uV_offset; int min_uA; int max_uA; int ilim_uA; int pw_budget_mW; int system_load; u32 *max_spread; int max_uV_step; unsigned int valid_modes_mask; unsigned int valid_ops_mask; int input_uV; struct regulator_state state_disk; struct regulator_state state_mem; struct regulator_state state_standby; struct notification_limit over_curr_limits; struct notification_limit over_voltage_limits; struct notification_limit under_voltage_limits; struct notification_limit temp_limits; suspend_state_t initial_state; unsigned int initial_mode; unsigned int ramp_delay; unsigned int settling_time; unsigned int settling_time_up; unsigned int settling_time_down; unsigned int enable_time; unsigned int uv_less_critical_window_ms; unsigned int active_discharge; unsigned always_on:1; unsigned boot_on:1; unsigned apply_uV:1; unsigned ramp_disable:1; unsigned soft_start:1; unsigned pull_down:1; unsigned system_critical:1; unsigned over_current_protection:1; unsigned over_current_detection:1; unsigned over_voltage_detection:1; unsigned under_voltage_detection:1; unsigned over_temp_detection:1;};Members
nameDescriptive name for the constraints, used for display purposes.
min_uVSmallest voltage consumers may set.
max_uVLargest voltage consumers may set.
uV_offsetOffset applied to voltages from consumer to compensate forvoltage drops.
min_uASmallest current consumers may set.
max_uALargest current consumers may set.
ilim_uAMaximum input current.
pw_budget_mWPower budget for the regulator in mW.
system_loadLoad that isn’t captured by any consumer requests.
max_spreadMax possible spread between coupled regulators
max_uV_stepMax possible step change in voltage
valid_modes_maskMask of modes which may be configured by consumers.
valid_ops_maskOperations which may be performed by consumers.
input_uVInput voltage for regulator when supplied by another regulator.
state_diskState for regulator when system is suspended in disk mode.
state_memState for regulator when system is suspended in mem mode.
state_standbyState for regulator when system is suspended in standbymode.
over_curr_limitsLimits for acting on over current.
over_voltage_limitsLimits for acting on over voltage.
under_voltage_limitsLimits for acting on under voltage.
temp_limitsLimits for acting on over temperature.
initial_stateSuspend state to set by default.
initial_modeMode to set at startup.
ramp_delayTime to settle down after voltage change (unit: uV/us)
settling_timeTime to settle down after voltage change when voltagechange is non-linear (unit: microseconds).
settling_time_upTime to settle down after voltage increase when voltagechange is non-linear (unit: microseconds).
settling_time_downTime to settle down after voltage decrease whenvoltage change is non-linear (unit: microseconds).
enable_timeTurn-on time of the rails (unit: microseconds)
uv_less_critical_window_msSpecifies the time window (in milliseconds)following a critical under-voltage (UV) eventduring which less critical actions can besafely carried out by the system (for examplelogging). After this time window more criticalactions should be done (for example preventHW damage).
active_dischargeEnable/disable active discharge. The
enumregulator_active_dischargevalues are used forinitialisation.always_onSet if the regulator should never be disabled.
boot_onSet if the regulator is enabled when the system is initiallystarted. If the regulator is not enabled by the hardware orbootloader then it will be enabled when the constraints areapplied.
apply_uVApply the voltage constraint when initialising.
ramp_disableDisable ramp delay when initialising or when setting voltage.
soft_startEnable soft start so that voltage ramps slowly.
pull_downEnable pull down when regulator is disabled.
system_criticalSet if the regulator is critical to system stability orfunctionality.
over_current_protectionAuto disable on over current event.
over_current_detectionConfigure over current limits.
over_voltage_detectionConfigure over voltage limits.
under_voltage_detectionConfigure under voltage limits.
over_temp_detectionConfigure over temperature limits.
Description
Thisstructdescribes regulator and board/machine specific constraints.
- structregulator_consumer_supply¶
supply -> device mapping
Definition:
struct regulator_consumer_supply { const char *dev_name; const char *supply;};Members
dev_nameResult of
dev_name()for the consumer.supplyName for the supply.
Description
This maps a supply name to a device. Use of dev_name allows support forbuses which makestructdevice available late such as I2C.
- structregulator_init_data¶
regulator platform initialisation data.
Definition:
struct regulator_init_data { const char *supply_regulator; struct regulation_constraints constraints; int num_consumer_supplies; struct regulator_consumer_supply *consumer_supplies; void *driver_data;};Members
supply_regulatorParent regulator. Specified using the regulator nameas it appears in the name field in sysfs, which canbe explicitly set using the constraints field ‘name’.
constraintsConstraints. These must be specified for the regulator tobe usable.
num_consumer_suppliesNumber of consumer device supplies.
consumer_suppliesConsumer device supply configuration.
driver_dataData passed to regulator_init.
Description
Initialisation constraints, our supply and consumers supplies.
- structregulator_ops¶
regulator operations.
Definition:
struct regulator_ops { int (*list_voltage) (struct regulator_dev *, unsigned selector); int (*set_voltage) (struct regulator_dev *, int min_uV, int max_uV, unsigned *selector); int (*map_voltage)(struct regulator_dev *, int min_uV, int max_uV); int (*set_voltage_sel) (struct regulator_dev *, unsigned selector); int (*get_voltage) (struct regulator_dev *); int (*get_voltage_sel) (struct regulator_dev *); int (*set_current_limit) (struct regulator_dev *, int min_uA, int max_uA); int (*get_current_limit) (struct regulator_dev *); int (*set_input_current_limit) (struct regulator_dev *, int lim_uA); int (*set_over_current_protection)(struct regulator_dev *, int lim_uA, int severity, bool enable); int (*set_over_voltage_protection)(struct regulator_dev *, int lim_uV, int severity, bool enable); int (*set_under_voltage_protection)(struct regulator_dev *, int lim_uV, int severity, bool enable); int (*set_thermal_protection)(struct regulator_dev *, int lim, int severity, bool enable); int (*set_active_discharge)(struct regulator_dev *, bool enable); int (*enable) (struct regulator_dev *); int (*disable) (struct regulator_dev *); int (*is_enabled) (struct regulator_dev *); int (*set_mode) (struct regulator_dev *, unsigned int mode); unsigned int (*get_mode) (struct regulator_dev *); int (*get_error_flags)(struct regulator_dev *, unsigned int *flags); int (*enable_time) (struct regulator_dev *); int (*set_ramp_delay) (struct regulator_dev *, int ramp_delay); int (*set_voltage_time) (struct regulator_dev *, int old_uV, int new_uV); int (*set_voltage_time_sel) (struct regulator_dev *, unsigned int old_selector, unsigned int new_selector); int (*set_soft_start) (struct regulator_dev *); int (*get_status)(struct regulator_dev *); unsigned int (*get_optimum_mode) (struct regulator_dev *, int input_uV, int output_uV, int load_uA); int (*set_load)(struct regulator_dev *, int load_uA); int (*set_bypass)(struct regulator_dev *dev, bool enable); int (*get_bypass)(struct regulator_dev *dev, bool *enable); int (*set_suspend_voltage) (struct regulator_dev *, int uV); int (*set_suspend_enable) (struct regulator_dev *); int (*set_suspend_disable) (struct regulator_dev *); int (*set_suspend_mode) (struct regulator_dev *, unsigned int mode); int (*resume)(struct regulator_dev *rdev); int (*set_pull_down) (struct regulator_dev *);};Members
list_voltageReturn one of the supported voltages, in microvolts; zeroif the selector indicates a voltage that is unusable on this system;or negative errno. Selectors range from zero to one less thanregulator_desc.n_voltages. Voltages may be reported in any order.
set_voltageSet the voltage for the regulator within the range specified.The driver should select the voltage closest to min_uV.
map_voltageConvert a voltage into a selector
set_voltage_selSet the voltage for the regulator using the specifiedselector.
get_voltageReturn the currently configured voltage for the regulator;return -ENOTRECOVERABLE if regulator can’t be read atbootup and hasn’t been set yet.
get_voltage_selReturn the currently configured voltage selector for theregulator; return -ENOTRECOVERABLE if regulator can’tbe read at bootup and hasn’t been set yet.
set_current_limitConfigure a limit for a current-limited regulator.The driver should select the current closest to max_uA.
get_current_limitGet the configured limit for a current-limited regulator.
set_input_current_limitConfigure an input limit.
set_over_current_protectionSupport enabling of and setting limits for overcurrent situation detection. Detection can be configured for threelevels of severity.
set_over_voltage_protectionSupport enabling of and setting limits for overvoltage situation detection. Detection can be configured for sameseverities as over current protection. Units of uV.
set_under_voltage_protectionSupport enabling of and setting limits forunder voltage situation detection. Detection can be configured for sameseverities as over current protection. Units of uV.
set_thermal_protectionSupport enabling of and setting limits for overtemperature situation detection.Detection can be configured for sameseverities as over current protection. Units of degree Kelvin.
set_active_dischargeSet active discharge enable/disable of regulators.
enableConfigure the regulator as enabled.
disableConfigure the regulator as disabled.
is_enabledReturn 1 if the regulator is enabled, 0 if not.May also return negative errno.
set_modeSet the configured operating mode for the regulator.
get_modeGet the configured operating mode for the regulator.
get_error_flagsGet the current error(s) for the regulator.
enable_timeTime taken for the regulator voltage output voltage tostabilise after being enabled, in microseconds.
set_ramp_delaySet the ramp delay for the regulator. The driver shouldselect ramp delay equal to or less than(closest) ramp_delay.
set_voltage_timeTime taken for the regulator voltage output voltageto stabilise after being set to a new value, in microseconds.The function receives the from and to voltage as input, itshould return the worst case.
set_voltage_time_selTime taken for the regulator voltage output voltageto stabilise after being set to a new value, in microseconds.The function receives the from and to voltage selector asinput, it should return the worst case.
set_soft_startEnable soft start for the regulator.
get_statusReturn actual (not as-configured) status of regulator, as aREGULATOR_STATUS value (or negative errno)
get_optimum_modeGet the most efficient operating mode for the regulatorwhen running with the specified parameters.
set_loadSet the load for the regulator.
set_bypassSet the regulator in bypass mode.
get_bypassGet the regulator bypass mode state.
set_suspend_voltageSet the voltage for the regulator when the systemis suspended.
set_suspend_enableMark the regulator as enabled when the system issuspended.
set_suspend_disableMark the regulator as disabled when the system issuspended.
set_suspend_modeSet the operating mode for the regulator when thesystem is suspended.
resumeResume operation of suspended regulator.
set_pull_downConfigure the regulator to pull down when the regulatoris disabled.
Description
REGULATOR_SEVERITY_PROT should automatically shut down the regulator(s).
- REGULATOR_SEVERITY_ERR should indicate that over-current situation is
caused by an unrecoverable error but HW does not performautomatic shut down.
- REGULATOR_SEVERITY_WARN should indicate situation where hardware is
still believed to not be damaged but that a board sepcificrecovery action is needed. If lim_uA is 0 the limit should notbe changed but the detection should just be enabled/disabled asis requested.
Thisstructdescribes regulator operations which can be implemented byregulator chip drivers.
- structregulator_desc¶
Static regulator descriptor
Definition:
struct regulator_desc { const char *name; const char *supply_name; const char *of_match; bool of_match_full_name; const char *regulators_node; int (*of_parse_cb)(struct device_node *, const struct regulator_desc *, struct regulator_config *); int (*init_cb)(struct regulator_dev *, struct regulator_config *); int id; unsigned int continuous_voltage_range:1; unsigned n_voltages; unsigned int n_current_limits; const struct regulator_ops *ops; int irq; enum regulator_type type; struct module *owner; unsigned int min_uV; unsigned int uV_step; unsigned int linear_min_sel; int fixed_uV; unsigned int ramp_delay; int min_dropout_uV; const struct linear_range *linear_ranges; const unsigned int *linear_range_selectors_bitfield; int n_linear_ranges; const unsigned int *volt_table; const unsigned int *curr_table; unsigned int vsel_range_reg; unsigned int vsel_range_mask; bool range_applied_by_vsel; unsigned int vsel_reg; unsigned int vsel_mask; unsigned int vsel_step; unsigned int csel_reg; unsigned int csel_mask; unsigned int apply_reg; unsigned int apply_bit; unsigned int enable_reg; unsigned int enable_mask; unsigned int enable_val; unsigned int disable_val; bool enable_is_inverted; unsigned int bypass_reg; unsigned int bypass_mask; unsigned int bypass_val_on; unsigned int bypass_val_off; unsigned int active_discharge_on; unsigned int active_discharge_off; unsigned int active_discharge_mask; unsigned int active_discharge_reg; unsigned int soft_start_reg; unsigned int soft_start_mask; unsigned int soft_start_val_on; unsigned int pull_down_reg; unsigned int pull_down_mask; unsigned int pull_down_val_on; unsigned int ramp_reg; unsigned int ramp_mask; const unsigned int *ramp_delay_table; unsigned int n_ramp_values; unsigned int enable_time; unsigned int off_on_delay; unsigned int poll_enabled_time; unsigned int (*of_map_mode)(unsigned int mode);};Members
nameIdentifying name for the regulator.
supply_nameIdentifying the regulator supply
of_matchName used to identify regulator in DT.
of_match_full_nameA flag to indicate that the of_match string, ifpresent, should be matched against the node full_name.
regulators_nodeName of node containing regulator definitions in DT.
of_parse_cbOptional callback called only if of_match is present.Will be called for each regulator parsed from DT, duringinit_data parsing.The regulator_config passed as argument to the callback willbe a copy of config passed to regulator_register, valid onlyfor this particular call. Callback may freely change theconfig but it cannot store it for later usage.Callback should return 0 on success or negative ERRNOindicating failure.
init_cbOptional callback called after the parsing of init_data.Allows the regulator to perform runtime init if necessary,such as synching the regulator and the parsed constraints.Callback should return 0 on success or negative ERRNOindicating failure.
idNumerical identifier for the regulator.
continuous_voltage_rangeIndicates if the regulator can set anyvoltage within constrains range.
n_voltagesNumber of selectors available for ops.
list_voltage().n_current_limitsNumber of selectors available for current limits
opsRegulator operations table.
irqInterrupt number for the regulator.
typeIndicates if the regulator is a voltage or current regulator.
ownerModule providing the regulator, used for refcounting.
min_uVVoltage given by the lowest selector (if linear mapping)
uV_stepVoltage increase with each selector (if linear mapping)
linear_min_selMinimal selector for starting linear mapping
fixed_uVFixed voltage of rails.
ramp_delayTime to settle down after voltage change (unit: uV/us)
min_dropout_uVThe minimum dropout voltage this regulator can handle
linear_rangesA constant table of possible voltage ranges.
linear_range_selectors_bitfieldA constant table of voltage rangeselectors as bitfield values. Ifpickable ranges are used each rangemust have corresponding selector here.
n_linear_rangesNumber of entries in thelinear_ranges (and inlinear_range_selectors_bitfield if used) table(s).
volt_tableVoltage mapping table (if table based mapping)
curr_tableCurrent limit mapping table (if table based mapping)
vsel_range_regRegister for range selector when using pickable rangesand
regulator_map_*_voltage_*_pickablefunctions.vsel_range_maskMask for register bitfield used for range selector
range_applied_by_vselA flag to indicate that changes to vsel_range_regare only effective after vsel_reg is written
vsel_regRegister for selector when using
regulator_map_*_voltage_*vsel_maskMask for register bitfield used for selector
vsel_stepSpecify the resolution of selector stepping when settingvoltage. If 0, then no stepping is done (requested selector isset directly), if >0 then the regulator API will ramp thevoltage up/down gradually each time increasing/decreasing theselector by the specified step value.
csel_regRegister for current limit selector using regmap set_current_limit
csel_maskMask for register bitfield used for current limit selector
apply_regRegister for initiate voltage change on the output whenusing regulator_set_voltage_sel_regmap
apply_bitRegister bitfield used for initiate voltage change on theoutput when using regulator_set_voltage_sel_regmap
enable_regRegister for control when using regmap enable/disable ops
enable_maskMask for control when using regmap enable/disable ops
enable_valEnabling value for control when using regmap enable/disable ops
disable_valDisabling value for control when using regmap enable/disable ops
enable_is_invertedA flag to indicate set enable_mask bits to disablewhen using regulator_enable_regmap and friends APIs.
bypass_regRegister for control when using regmap set_bypass
bypass_maskMask for control when using regmap set_bypass
bypass_val_onEnabling value for control when using regmap set_bypass
bypass_val_offDisabling value for control when using regmap set_bypass
active_discharge_onDisabling value for control when using regmapset_active_discharge
active_discharge_offEnabling value for control when using regmapset_active_discharge
active_discharge_maskMask for control when using regmapset_active_discharge
active_discharge_regRegister for control when using regmapset_active_discharge
soft_start_regRegister for control when using regmap set_soft_start
soft_start_maskMask for control when using regmap set_soft_start
soft_start_val_onEnabling value for control when using regmapset_soft_start
pull_down_regRegister for control when using regmap set_pull_down
pull_down_maskMask for control when using regmap set_pull_down
pull_down_val_onEnabling value for control when using regmapset_pull_down
ramp_regRegister for controlling the regulator ramp-rate.
ramp_maskBitmask for the ramp-rate control register.
ramp_delay_tableTable for mapping the regulator ramp-rate values. Valuesshould be given in units of V/S (uV/uS). See the
regulator_set_ramp_delay_regmap().n_ramp_valuesnumber of elements atramp_delay_table.
enable_timeTime taken for initial enable of regulator (in uS).
off_on_delayguard time (in uS), before re-enabling a regulator
poll_enabled_timeThe polling interval (in uS) to use while checking thatthe regulator was actually enabled. Max upto enable_time.
of_map_modeMaps a hardware mode defined in a DeviceTree to a standard mode
Description
Each regulator registered with the core is described with astructure of this type and astructregulator_config. Thisstructure contains the non-varying parts of the regulatordescription.
- structregulator_config¶
Dynamic regulator descriptor
Definition:
struct regulator_config { struct device *dev; const struct regulator_init_data *init_data; void *driver_data; struct device_node *of_node; struct regmap *regmap; struct gpio_desc *ena_gpiod;};Members
devstructdevicefor the regulatorinit_dataplatform provided init data, passed through by driver
driver_dataprivate regulator data
of_nodeOpenFirmware node to parse for device tree bindings (may beNULL).
regmapregmap to use for core regmap helpers if
dev_get_regmap()isinsufficient.ena_gpiodGPIO controlling regulator enable.
Description
Each regulator registered with the core is described with astructure of this type and astructregulator_desc. This structurecontains the runtime variable parts of the regulator description.
- structregulator_err_state¶
regulator error/notification status
Definition:
struct regulator_err_state { struct regulator_dev *rdev; unsigned long notifs; unsigned long errors; int possible_errs;};Members
rdevRegulator which status the
structindicates.notifsEvents which have occurred on the regulator.
errorsErrors which are active on the regulator.
possible_errsErrors which can be signaled (by given IRQ).
- structregulator_irq_data¶
regulator error/notification status data
Definition:
struct regulator_irq_data { struct regulator_err_state *states; int num_states; void *data; long opaque;};Members
statesStatus structs for each of the associated regulators.
num_statesAmount of associated regulators.
dataDriver data pointer given at regulator_irq_desc.
opaqueValue storage for IC driver. Core does not update this. ICsmay want to store status register value here at map_event andcompare contents at ‘renable’ callback to see if new problemshave been added to status. If that is the case it may bedesirable to return REGULATOR_ERROR_CLEARED and notREGULATOR_ERROR_ON to allow IRQ fire again and to generatenotifications also for the new issues.
Description
This structure is passed to ‘map_event’ and ‘renable’ callbacks forreporting regulator status to core.
- structregulator_irq_desc¶
notification sender for IRQ based events.
Definition:
struct regulator_irq_desc { const char *name; int fatal_cnt; int reread_ms; int irq_off_ms; bool skip_off; bool high_prio; void *data; int (*die)(struct regulator_irq_data *rid); int (*map_event)(int irq, struct regulator_irq_data *rid, unsigned long *dev_mask); int (*renable)(struct regulator_irq_data *rid);};Members
nameThe visible name for the IRQ
fatal_cntIf this IRQ is used to signal HW damaging condition it may bebest to shut-down regulator(s) or reboot the SOC if errorhandling is repeatedly failing. If fatal_cnt is given the IRQhandling is aborted if it fails for fatal_cnt times and
die()callback (if populated) is called. Ifdie()is not populatedpoweroff for the system is attempted in order to prevent anyfurther damage.reread_msThe time which is waited before attempting to re-read statusat the worker if IC reading fails. Immediate re-read is doneif time is not specified.
irq_off_msThe time which IRQ is kept disabled before re-evaluating thestatus for devices which keep IRQ disabled for duration of theerror. If this is not given the IRQ is left enabled and renableis not called.
skip_offIf set to true the IRQ handler will attempt to check if any ofthe associated regulators are enabled prior to taking otheractions. If no regulators are enabled and this is set to truea spurious IRQ is assumed and IRQ_NONE is returned.
high_prioBoolean to indicate that high priority WQ should be used.
dataDriver private data pointer which will be passed as such tothe renable, map_event and die callbacks in regulator_irq_data.
dieProtection callback. If IC status reading or recovery actionsfail fatal_cnt times this callback is called or system ispowered off. This callback should implement a final protectionattempt like disabling the regulator. If protection succeeded
die()may return 0. If anything else is returned the coreassumes final protection failed and attempts to perform apoweroff as a last resort.map_eventDriver callback to map IRQ status into regulator devices withevents / errors. NOTE: callback MUST initialize both theerrors and notifs for all rdevs which it signals havingactive events as core does not clean the map data.REGULATOR_FAILED_RETRY can be returned to indicate that thestatus reading from IC failed. If this is repeated forfatal_cnt times the core will call
die()callback or power-offthe system as a last resort to protect the HW.renableOptional callback to check status (if HW supports that) beforere-enabling IRQ. If implemented this should clear the errorflags so that errors fetched by
regulator_get_error_flags()are updated. If callback is not implemented then errors areassumed to be cleared and IRQ is re-enabled.REGULATOR_FAILED_RETRY can be returned toindicate that the status reading from IC failed. If this isrepeated for ‘fatal_cnt’ times the core will calldie()callback or ifdie()is not populated then attempt to power-offthe system as a last resort to protect the HW.Returning zero indicates that the problem in HW has been solvedand IRQ will be re-enabled. Returning REGULATOR_ERROR_ONindicates the error condition is still active and keeps IRQdisabled. Please note that returning REGULATOR_ERROR_ON doesnot retrigger evaluating what events are active or resendingnotifications. If this is needed you probably want to returnzero and allow IRQ to retrigger causing events to bere-evaluated and re-sent.
Description
This structure is used for registering regulator IRQ notification helper.
- structregulator*regulator_get(structdevice*dev,constchar*id)¶
lookup and obtain a reference to a regulator.
Parameters
structdevice*devdevice for regulator “consumer”
constchar*idSupply name or regulator ID.
Description
Use of supply names configured viaset_consumer_device_supply() isstrongly encouraged. It is recommended that the supply name usedshould match the name used for the supply and/or the relevantdevice pins in the datasheet.
Return
Pointer to astructregulator corresponding to the regulatorproducer, or anERR_PTR() encoded negative error number.
- structregulator*regulator_get_exclusive(structdevice*dev,constchar*id)¶
obtain exclusive access to a regulator.
Parameters
structdevice*devdevice for regulator “consumer”
constchar*idSupply name or regulator ID.
Description
Other consumers will be unable to obtain this regulator while thisreference is held and the use count for the regulator will beinitialised to reflect the current state of the regulator.
This is intended for use by consumers which cannot tolerate shareduse of the regulator such as those which need to force theregulator off for correct operation of the hardware they arecontrolling.
Use of supply names configured viaset_consumer_device_supply() isstrongly encouraged. It is recommended that the supply name usedshould match the name used for the supply and/or the relevantdevice pins in the datasheet.
Return
Pointer to astructregulator corresponding to the regulatorproducer, or anERR_PTR() encoded negative error number.
- structregulator*regulator_get_optional(structdevice*dev,constchar*id)¶
obtain optional access to a regulator.
Parameters
structdevice*devdevice for regulator “consumer”
constchar*idSupply name or regulator ID.
Description
This is intended for use by consumers for devices which can havesome supplies unconnected in normal use, such as some MMC devices.It can allow the regulator core to provide stub supplies for othersupplies requested using normalregulator_get() calls withoutdisrupting the operation of drivers that can handle absentsupplies.
Use of supply names configured viaset_consumer_device_supply() isstrongly encouraged. It is recommended that the supply name usedshould match the name used for the supply and/or the relevantdevice pins in the datasheet.
Return
Pointer to astructregulator corresponding to the regulatorproducer, or anERR_PTR() encoded negative error number.
Parameters
structregulator*regulatorregulator source
Note
drivers must ensure that all regulator_enable calls made on thisregulator source are balanced by regulator_disable calls prior to callingthis function.
- intregulator_register_supply_alias(structdevice*dev,constchar*id,structdevice*alias_dev,constchar*alias_id)¶
Provide device alias for supply lookup
Parameters
structdevice*devdevice that will be given as the regulator “consumer”
constchar*idSupply name or regulator ID
structdevice*alias_devdevice that should be used to lookup the supply
constchar*alias_idSupply name or regulator ID that should be used to lookup thesupply
Description
All lookups for id on dev will instead be conducted for alias_id onalias_dev.
Return
0 on success or a negative error number on failure.
Parameters
structdevice*devdevice that will be given as the regulator “consumer”
constchar*idSupply name or regulator ID
Description
Remove a lookup alias if one exists for id on dev.
- intregulator_bulk_register_supply_alias(structdevice*dev,constchar*const*id,structdevice*alias_dev,constchar*const*alias_id,intnum_id)¶
register multiple aliases
Parameters
structdevice*devdevice that will be given as the regulator “consumer”
constchar*const*idList of supply names or regulator IDs
structdevice*alias_devdevice that should be used to lookup the supply
constchar*const*alias_idList of supply names or regulator IDs that should be used tolookup the supply
intnum_idNumber of aliases to register
Description
This helper function allows drivers to register several supplyaliases in one operation. If any of the aliases cannot beregistered any aliases that were registered will be removedbefore returning to the caller.
Return
0 on success or a negative error number on failure.
- voidregulator_bulk_unregister_supply_alias(structdevice*dev,constchar*const*id,intnum_id)¶
unregister multiple aliases
Parameters
structdevice*devdevice that will be given as the regulator “consumer”
constchar*const*idList of supply names or regulator IDs
intnum_idNumber of aliases to unregister
Description
This helper function allows drivers to unregister several supplyaliases in one operation.
Parameters
structregulator*regulatorregulator source
Description
Request that the regulator be enabled with the regulator output atthe predefined voltage or current value. Calls toregulator_enable()must be balanced with calls toregulator_disable().
NOTE
the output value can be set by other drivers, boot loader or may behardwired in the regulator.
Return
0 on success or a negative error number on failure.
Parameters
structregulator*regulatorregulator source
Description
Disable the regulator output voltage or current. Calls toregulator_enable() must be balanced with calls toregulator_disable().
NOTE
this will only disable the regulator output if no other consumerdevices have it enabled, the regulator device supports disabling andmachine constraints permit this operation.
Return
0 on success or a negative error number on failure.
Parameters
structregulator*regulatorregulator source
Description
Forcibly disable the regulator output voltage or current.
NOTE
thiswill disable the regulator output even if other consumerdevices have it enabled. This should be used for situations when devicedamage will likely occur if the regulator is not disabled (e.g. over temp).
Return
0 on success or a negative error number on failure.
Parameters
structregulator*regulatorregulator source
intmsmilliseconds until the regulator is disabled
Description
Executeregulator_disable() on the regulator after a delay. Thisis intended for use with devices that require some time to quiesce.
NOTE
this will only disable the regulator output if no other consumerdevices have it enabled, the regulator device supports disabling andmachine constraints permit this operation.
Return
0 on success or a negative error number on failure.
Parameters
structregulator*regulatorregulator source
Description
Note that the device backing this regulator handle can have multipleusers, so it might be enabled even ifregulator_enable() was nevercalled for this particular source.
Return
Positive if the regulator driver backing the source/clienthas requested that the device be enabled, zero if it hasn’t,else a negative error number.
- intregulator_count_voltages(structregulator*regulator)¶
count
regulator_list_voltage()selectors
Parameters
structregulator*regulatorregulator source
Return
Number of selectors forregulator, or negative error number.
Description
Selectors are numbered starting at zero, and typically correspond tobitfields in hardware registers.
Parameters
structregulator*regulatorregulator source
unsignedselectoridentify voltage to list
Context
can sleep
Return
Voltage forselector that can be passed toregulator_set_voltage(),0 ifselector can’t be used on this system, or a negative errornumber on failure.
Parameters
structregulator*regulatorregulator source
Return
Pointer to thestructregmap forregulator, orERR_PTR()encoded -EOPNOTSUPP ifregulator doesn’t use regmap.
- intregulator_get_hardware_vsel_register(structregulator*regulator,unsigned*vsel_reg,unsigned*vsel_mask)¶
get the HW voltage selector register
Parameters
structregulator*regulatorregulator source
unsigned*vsel_regvoltage selector register, output parameter
unsigned*vsel_maskmask for voltage selector bitfield, output parameter
Description
Returns the hardware register offset and bitmask used for setting theregulator voltage. This might be useful when configuring voltage-scalinghardware or firmware that can make I2C requests behind the kernel’s back,for example.
On success, the output parametersvsel_reg andvsel_mask are filled inand 0 is returned, otherwise a negative error number is returned.
Return
0 on success, or -EOPNOTSUPP if the regulator does not supportvoltage selectors.
- intregulator_list_hardware_vsel(structregulator*regulator,unsignedselector)¶
get the HW-specific register value for a selector
Parameters
structregulator*regulatorregulator source
unsignedselectoridentify voltage to list
Description
Converts the selector to a hardware-specific voltage selector that can bedirectly written to the regulator registers. The address of the voltageregister can be determined by callingregulator_get_hardware_vsel_register.
Return
0 on success, -EINVAL if the selector is outside the supportedrange, or -EOPNOTSUPP if the regulator does not support voltageselectors.
- intregulator_hardware_enable(structregulator*regulator,boolenable)¶
access the HW for enable/disable regulator
Parameters
structregulator*regulatorregulator source
boolenabletrue for enable, false for disable
Description
Request that the regulator be enabled/disabled with the regulator output atthe predefined voltage or current value.
Return
0 on success or a negative error number on failure.
- unsignedintregulator_get_linear_step(structregulator*regulator)¶
return the voltage step size between VSEL values
Parameters
structregulator*regulatorregulator source
Return
The voltage step size between VSEL values for linear regulators,or 0 if the regulator isn’t a linear regulator.
- intregulator_is_supported_voltage(structregulator*regulator,intmin_uV,intmax_uV)¶
check if a voltage range can be supported
Parameters
structregulator*regulatorRegulator to check.
intmin_uVMinimum required voltage in uV.
intmax_uVMaximum required voltage in uV.
Return
1 if the voltage range is supported, 0 if not, or a negative errornumber ifregulator’s voltage can’t be changed and voltage readbackfailed.
- intregulator_set_voltage(structregulator*regulator,intmin_uV,intmax_uV)¶
set regulator output voltage
Parameters
structregulator*regulatorregulator source
intmin_uVMinimum required voltage in uV
intmax_uVMaximum acceptable voltage in uV
Description
Sets a voltage regulator to the desired output voltage. This can be setduring any regulator state. IOW, regulator can be disabled or enabled.
If the regulator is enabled then the voltage will change to the new valueimmediately otherwise if the regulator is disabled the regulator willoutput at the new voltage when enabled.
NOTE
If the regulator is shared between several devices then the lowestrequest voltage that meets the system constraints will be used.Regulator system constraints must be set for this regulator beforecalling this function otherwise this call will fail.
Return
0 on success or a negative error number on failure.
Parameters
structregulator*regulatorregulator source
intold_uVstarting voltage in microvolts
intnew_uVtarget voltage in microvolts
Description
Provided with the starting and ending voltage, this function attempts tocalculate the time in microseconds required to rise or fall to this newvoltage.
Return
ramp time in microseconds, or a negative error number if calculation failed.
- intregulator_set_voltage_time_sel(structregulator_dev*rdev,unsignedintold_selector,unsignedintnew_selector)¶
get raise/fall time
Parameters
structregulator_dev*rdevregulator source device
unsignedintold_selectorselector for starting voltage
unsignedintnew_selectorselector for target voltage
Description
Provided with the starting and target voltage selectors, this functionreturns time in microseconds required to rise or fall to this new voltage
Drivers providing ramp_delay in regulation_constraints can use this as theirset_voltage_time_sel() operation.
Return
ramp time in microseconds, or a negative error number if calculation failed.
Parameters
structregulator*regulatorregulator source
Description
Re-apply the last configured voltage. This is intended to be usedwhere some external control source the consumer is cooperating withhas caused the configured voltage to change.
Return
0 on success or a negative error number on failure.
Parameters
structregulator*regulatorregulator source
Return
Current regulator voltage in uV, or a negative error number on failure.
NOTE
If the regulator is disabled it will return the voltage value. Thisfunction should not be used to determine regulator state.
- intregulator_set_current_limit(structregulator*regulator,intmin_uA,intmax_uA)¶
set regulator output current limit
Parameters
structregulator*regulatorregulator source
intmin_uAMinimum supported current in uA
intmax_uAMaximum supported current in uA
Description
Sets current sink to the desired output current. This can be set duringany regulator state. IOW, regulator can be disabled or enabled.
If the regulator is enabled then the current will change to the new valueimmediately otherwise if the regulator is disabled the regulator willoutput at the new current when enabled.
NOTE
Regulator system constraints must be set for this regulator beforecalling this function otherwise this call will fail.
Return
0 on success or a negative error number on failure.
Parameters
structregulator*regulatorregulator source
Return
Current supplied by the specified current sink in uA,or a negative error number on failure.
NOTE
If the regulator is disabled it will return the current value. Thisfunction should not be used to determine regulator state.
- intregulator_get_unclaimed_power_budget(structregulator*regulator)¶
get regulator unclaimed power budget
Parameters
structregulator*regulatorregulator source
Return
Unclaimed power budget of the regulator in mW.
- intregulator_request_power_budget(structregulator*regulator,unsignedintpw_req)¶
request power budget on a regulator
Parameters
structregulator*regulatorregulator source
unsignedintpw_reqPower requested
Return
0 on success or a negative error number on failure.
- voidregulator_free_power_budget(structregulator*regulator,unsignedintpw)¶
free power budget on a regulator
Parameters
structregulator*regulatorregulator source
unsignedintpwPower to be released.
Return
Power budget of the regulator in mW.
Parameters
structregulator*regulatorregulator source
unsignedintmodeoperating mode - one of the REGULATOR_MODE constants
Description
Set regulator operating mode to increase regulator efficiency or improveregulation performance.
NOTE
Regulator system constraints must be set for this regulator beforecalling this function otherwise this call will fail.
Return
0 on success or a negative error number on failure.
Parameters
structregulator*regulatorregulator source
Description
Get the current regulator operating mode.
Return
Current operating mode asREGULATOR_MODE_* values,or a negative error number on failure.
- intregulator_get_error_flags(structregulator*regulator,unsignedint*flags)¶
get regulator error information
Parameters
structregulator*regulatorregulator source
unsignedint*flagspointer to store error flags
Description
Get the current regulator error information.
Return
0 on success or a negative error number on failure.
Parameters
structregulator*regulatorregulator source
intuA_loadload current
Description
Notifies the regulator core of a new device load. This is then used byDRMS (if enabled by constraints) to set the most efficient regulatoroperating mode for the new regulator loading.
Consumer devices notify their supply regulator of the maximum powerthey will require (can be taken from device datasheet in the powerconsumption tables) when they change operational status and hence powerstate. Examples of operational state changes that can affect powerconsumption are :-
o Device is opened / closed.o Device I/O is about to begin or has just finished.o Device is idling in between work.
This information is also exported via sysfs to userspace.
DRMS will sum the total requested load on the regulator and changeto the most efficient operating mode if platform constraints allow.
NOTE
when a regulator consumer requests to have a regulatordisabled then any load that consumer requested no longer countstoward the total requested load. If the regulator is re-enabledthen the previously requested load will start counting again.
If a regulator is an always-on regulator then an individual consumer’sload will still be removed if that consumer is fully disabled.
Return
0 on success or a negative error number on failure.
- intregulator_allow_bypass(structregulator*regulator,boolenable)¶
allow the regulator to go into bypass mode
Parameters
structregulator*regulatorRegulator to configure
boolenableenable or disable bypass mode
Description
Allow the regulator to go into bypass mode if all other consumersfor the regulator also enable bypass mode and the machineconstraints allow this. Bypass mode means that the regulator issimply passing the input directly to the output with no regulation.
Return
0 on success or if changing bypass is not possible, ora negative error number on failure.
- intregulator_register_notifier(structregulator*regulator,structnotifier_block*nb)¶
register regulator event notifier
Parameters
structregulator*regulatorregulator source
structnotifier_block*nbnotifier block
Description
Register notifier block to receive regulator events.
Return
0 on success or a negative error number on failure.
- intregulator_unregister_notifier(structregulator*regulator,structnotifier_block*nb)¶
unregister regulator event notifier
Parameters
structregulator*regulatorregulator source
structnotifier_block*nbnotifier block
Description
Unregister regulator event notifier block.
Return
0 on success or a negative error number on failure.
- intregulator_bulk_get(structdevice*dev,intnum_consumers,structregulator_bulk_data*consumers)¶
get multiple regulator consumers
Parameters
structdevice*devDevice to supply
intnum_consumersNumber of consumers to register
structregulator_bulk_data*consumersConfiguration of consumers; clients are stored here.
Description
This helper function allows drivers to get several regulatorconsumers in one operation. If any of the regulators cannot beacquired then any regulators that were allocated will be freedbefore returning to the caller.
Return
0 on success or a negative error number on failure.
- intregulator_bulk_enable(intnum_consumers,structregulator_bulk_data*consumers)¶
enable multiple regulator consumers
Parameters
intnum_consumersNumber of consumers
structregulator_bulk_data*consumersConsumer data; clients are stored here.
Description
This convenience API allows consumers to enable multiple regulatorclients in a single API call. If any consumers cannot be enabledthen any others that were enabled will be disabled again prior toreturn.
Return
0 on success or a negative error number on failure.
- intregulator_bulk_disable(intnum_consumers,structregulator_bulk_data*consumers)¶
disable multiple regulator consumers
Parameters
intnum_consumersNumber of consumers
structregulator_bulk_data*consumersConsumer data; clients are stored here.
Description
This convenience API allows consumers to disable multiple regulatorclients in a single API call. If any consumers cannot be disabledthen any others that were disabled will be enabled again prior toreturn.
Return
0 on success or a negative error number on failure.
- intregulator_bulk_force_disable(intnum_consumers,structregulator_bulk_data*consumers)¶
force disable multiple regulator consumers
Parameters
intnum_consumersNumber of consumers
structregulator_bulk_data*consumersConsumer data; clients are stored here.
Description
This convenience API allows consumers to forcibly disable multiple regulatorclients in a single API call.
NOTE
This should be used for situations when device damage willlikely occur if the regulators are not disabled (e.g. over temp).Although regulator_force_disable function call for some consumers canreturn error numbers, the function is called for all consumers.
Return
0 on success or a negative error number on failure.
- voidregulator_bulk_free(intnum_consumers,structregulator_bulk_data*consumers)¶
free multiple regulator consumers
Parameters
intnum_consumersNumber of consumers
structregulator_bulk_data*consumersConsumer data; clients are stored here.
Description
This convenience API allows consumers to free multiple regulatorclients in a single API call.
- intregulator_notifier_call_chain(structregulator_dev*rdev,unsignedlongevent,void*data)¶
call regulator event notifier
Parameters
structregulator_dev*rdevregulator source
unsignedlongeventnotifier block
void*datacallback-specific data.
Description
Called by regulator drivers to notify clients a regulator event hasoccurred.
Return
NOTIFY_DONE.
- intregulator_mode_to_status(unsignedintmode)¶
convert a regulator mode into a status
Parameters
unsignedintmodeMode to convert
Description
Convert a regulator mode into a status.
Return
REGULATOR_STATUS_* value corresponding to given mode.
- structregulator_dev*regulator_register(structdevice*dev,conststructregulator_desc*regulator_desc,conststructregulator_config*cfg)¶
register regulator
Parameters
structdevice*devthe device that drive the regulator
conststructregulator_desc*regulator_descregulator to register
conststructregulator_config*cfgruntime configuration for regulator
Description
Called by regulator drivers to register a regulator.
Return
Pointer to a validstructregulator_dev on success oranERR_PTR() encoded negative error number on failure.
- voidregulator_unregister(structregulator_dev*rdev)¶
unregister regulator
Parameters
structregulator_dev*rdevregulator to unregister
Description
Called by regulator drivers to unregister a regulator.
- voidregulator_has_full_constraints(void)¶
the system has fully specified constraints
Parameters
voidno arguments
Description
Calling this function will cause the regulator API to disable allregulators which have a zero use count and don’t have an always_onconstraint in a late_initcall.
The intention is that this will become the default behaviour in afuture kernel release so users are encouraged to use this facilitynow.
- void*rdev_get_drvdata(structregulator_dev*rdev)¶
get rdev regulator driver data
Parameters
structregulator_dev*rdevregulator
Description
Get rdev regulator driver private data. This call can be used in theregulator driver context.
Return
Pointer to regulator driver private data.
Parameters
structregulator*regulatorregulator
Description
Get regulator driver private data. This call can be used in the consumerdriver context when non API regulator specific functions need to be called.
Return
Pointer to regulator driver private data.
Parameters
structregulator*regulatorregulator
void*datadata
- intrdev_get_id(structregulator_dev*rdev)¶
get regulator ID
Parameters
structregulator_dev*rdevregulator
Return
Regulator ID forrdev.