Voltage and current regulator API¶
Author: | Liam Girdwood |
---|---|
Author: | Mark Brown |
Introduction¶
This framework is designed to provide a standard kernel interface to control voltage and current regulators.
The intention is to allow systems to dynamically control regulator power output in order to save power and prolong battery life. This applies to both voltage regulators (where voltage output is controllable) and current sinks (where current limit is controllable).
Note that additional (and currently more complete) documentation is
available in the Linux kernel source under
Documentation/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 regulators can enable and disable their output and some can also control their output voltage or current.
Consumer
Electronic device which consumes power provided by a regulator. These may 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 the regulator and all consumer devices. The configuration of the regulator is shared between all the components in the circuit.
Power Management Integrated Circuit (PMIC)
An IC which contains numerous regulators and often also other subsystems. In an embedded system the primary PMIC is often equivalent to a combination of the PSU and southbridge in a desktop system.
Consumer driver interface¶
This offers a similar API to the kernel clock framework. Consumer drivers use get and put operations to acquire and release regulators. Functions are provided to enable and disable the regulator and to get and set the runtime parameters of the regulator.
When requesting regulators consumers use symbolic names for their supplies, such as “Vcc”, which are mapped into actual regulator devices by the machine interface.
A stub version of this API is provided when the regulator framework is not in use in order to minimise the need to use ifdefs.
Enabling and disabling¶
The regulator API provides reference counted enabling and disabling of
regulators. Consumer devices use the regulator_enable()
and
regulator_disable()
functions to enable and disable
regulators. Calls to the two functions must be balanced.
Note that since multiple consumers may be using a regulator and machine
constraints may not allow the regulator to be disabled there is no
guarantee that calling regulator_disable()
will actually
cause the supply provided by the regulator to be disabled. Consumer
drivers should assume that the regulator may be enabled at all times.
Configuration¶
Some consumer devices may need to be able to dynamically configure their supplies. For example, MMC drivers may need to select the correct operating voltage for their cards. This may be done while the regulator is enabled or disabled.
The regulator_set_voltage()
and
regulator_set_current_limit()
functions provide the primary
interface for this. Both take ranges of voltages and currents, supporting
drivers that do not require a specific value (eg, CPU frequency scaling
normally permits the CPU to use a wider range of supply voltages at lower
frequencies but does not require that the supply voltage be lowered). Where
an exact value is required both minimum and maximum values should be
identical.
Callbacks¶
Callbacks may also be registered for events such as regulation failures.
Regulator driver interface¶
Drivers for regulator chips register the regulators with the regulator core, providing operations structures to the core. A notifier interface allows error conditions to be reported to the core.
Registration should be triggered by explicit setup done by the platform,
supplying a struct regulator_init_data
for the regulator
containing constraint and supply information.
Machine interface¶
This interface provides a way to define how regulators are connected to consumers on a given system and what the valid operating parameters are for the system.
Supplies¶
Regulator supplies are specified using struct
regulator_consumer_supply
. This is done at driver registration
time as part of the machine constraints.
Constraints¶
As well as defining the connections the machine interface also provides constraints defining the operations that clients are allowed to perform and the parameters that may be set. This is required since generally regulator devices will offer more flexibility than it is safe to use on a given system, for example supporting higher supply voltages than the consumers are rated for.
This is done at driver registration time` by providing a
struct regulation_constraints
.
The constraints may also specify an initial configuration for the regulator in the constraints, which is particularly useful for use with static consumers.
API reference¶
Due to limitations of the kernel documentation framework and the existing layout of the source code the entire regulator API is documented here.
-
struct
pre_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_uV
- Current voltage before change.
min_uV
- Min voltage we’ll change to.
max_uV
- Max voltage we’ll change to.
-
struct
regulator_bulk_data
¶ Data used for bulk regulator operations.
Definition
struct regulator_bulk_data {
const char * supply;
struct regulator * consumer;
};
Members
supply
- The name of the supply. Initialised by the user before using the bulk regulator APIs.
consumer
- The regulator consumer for the supply. This will be managed by the bulk API.
Description
The regulator APIs provide a series of regulator_bulk_()
API calls as
a convenience to consumers which require multiple supplies. This
structure is used to manage data for these calls.
-
struct
regulator_state
¶ regulator state during low power system states
Definition
struct regulator_state {
int uV;
unsigned int mode;
int enabled;
int disabled;
};
Members
uV
- Operating voltage during suspend.
mode
- Operating mode during suspend.
enabled
- Enabled during suspend.
disabled
- Disabled during suspend.
Description
This describes a regulators state during a system wide low power state. One of enabled or disabled must be set for the configuration to be applied.
-
struct
regulation_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 system_load;
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;
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 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 over_current_protection:1;
};
Members
name
- Descriptive name for the constraints, used for display purposes.
min_uV
- Smallest voltage consumers may set.
max_uV
- Largest voltage consumers may set.
uV_offset
- Offset applied to voltages from consumer to compensate for voltage drops.
min_uA
- Smallest current consumers may set.
max_uA
- Largest current consumers may set.
ilim_uA
- Maximum input current.
system_load
- Load that isn’t captured by any consumer requests.
valid_modes_mask
- Mask of modes which may be configured by consumers.
valid_ops_mask
- Operations which may be performed by consumers.
input_uV
- Input voltage for regulator when supplied by another regulator.
state_disk
- State for regulator when system is suspended in disk mode.
state_mem
- State for regulator when system is suspended in mem mode.
state_standby
- State for regulator when system is suspended in standby mode.
initial_state
- Suspend state to set by default.
initial_mode
- Mode to set at startup.
ramp_delay
- Time to settle down after voltage change (unit: uV/us)
settling_time
- Time to settle down after voltage change when voltage change is non-linear (unit: microseconds).
settling_time_up
- Time to settle down after voltage increase when voltage change is non-linear (unit: microseconds).
settling_time_down
- Time to settle down after voltage decrease when voltage change is non-linear (unit: microseconds).
enable_time
- Turn-on time of the rails (unit: microseconds)
active_discharge
- Enable/disable active discharge. The enum regulator_active_discharge values are used for initialisation.
always_on
- Set if the regulator should never be disabled.
boot_on
- Set if the regulator is enabled when the system is initially started. If the regulator is not enabled by the hardware or bootloader then it will be enabled when the constraints are applied.
apply_uV
- Apply the voltage constraint when initialising.
ramp_disable
- Disable ramp delay when initialising or when setting voltage.
soft_start
- Enable soft start so that voltage ramps slowly.
pull_down
- Enable pull down when regulator is disabled.
over_current_protection
- Auto disable on over current event.
Description
This struct describes regulator and board/machine specific constraints.
-
struct
regulator_consumer_supply
¶ supply -> device mapping
Definition
struct regulator_consumer_supply {
const char * dev_name;
const char * supply;
};
Members
dev_name
- Result of
dev_name()
for the consumer. supply
- Name for the supply.
Description
This maps a supply name to a device. Use of dev_name allows support for buses which make struct device available late such as I2C.
-
struct
regulator_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;
int (* regulator_init) (void *driver_data);
void * driver_data;
};
Members
supply_regulator
- Parent regulator. Specified using the regulator name as it appears in the name field in sysfs, which can be explicitly set using the constraints field ‘name’.
constraints
- Constraints. These must be specified for the regulator to be usable.
num_consumer_supplies
- Number of consumer device supplies.
consumer_supplies
- Consumer device supply configuration.
regulator_init
- Callback invoked when the regulator has been registered.
driver_data
- Data passed to regulator_init.
Description
Initialisation constraints, our supply and consumers supplies.
-
struct
regulator_linear_range
¶ specify linear voltage ranges
Definition
struct regulator_linear_range {
unsigned int min_uV;
unsigned int min_sel;
unsigned int max_sel;
unsigned int uV_step;
};
Members
min_uV
- Lowest voltage in range
min_sel
- Lowest selector for range
max_sel
- Highest selector for range
uV_step
- Step size
Description
Specify a range of voltages for regulator_map_linar_range()
and
regulator_list_linear_range()
.
-
struct
regulator_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 (* 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 (* set_pull_down) (struct regulator_dev *);
};
Members
list_voltage
- Return one of the supported voltages, in microvolts; zero if the selector indicates a voltage that is unusable on this system; or negative errno. Selectors range from zero to one less than regulator_desc.n_voltages. Voltages may be reported in any order.
set_voltage
- Set the voltage for the regulator within the range specified. The driver should select the voltage closest to min_uV.
map_voltage
- Convert a voltage into a selector
set_voltage_sel
- Set the voltage for the regulator using the specified selector.
get_voltage
- Return the currently configured voltage for the regulator.
get_voltage_sel
- Return the currently configured voltage selector for the regulator.
set_current_limit
- Configure a limit for a current-limited regulator. The driver should select the current closest to max_uA.
get_current_limit
- Get the configured limit for a current-limited regulator.
set_input_current_limit
- Configure an input limit.
set_over_current_protection
- Support capability of automatically shutting down when detecting an over current event.
set_active_discharge
- Set active discharge enable/disable of regulators.
enable
- Configure the regulator as enabled.
disable
- Configure the regulator as disabled.
is_enabled
- Return 1 if the regulator is enabled, 0 if not. May also return negative errno.
set_mode
- Set the configured operating mode for the regulator.
get_mode
- Get the configured operating mode for the regulator.
get_error_flags
- Get the current error(s) for the regulator.
enable_time
- Time taken for the regulator voltage output voltage to stabilise after being enabled, in microseconds.
set_ramp_delay
- Set the ramp delay for the regulator. The driver should select ramp delay equal to or less than(closest) ramp_delay.
set_voltage_time
- Time taken for the regulator voltage output voltage to stabilise after being set to a new value, in microseconds. The function receives the from and to voltage as input, it should return the worst case.
set_voltage_time_sel
- Time taken for the regulator voltage output voltage to stabilise after being set to a new value, in microseconds. The function receives the from and to voltage selector as input, it should return the worst case.
set_soft_start
- Enable soft start for the regulator.
get_status
- Return actual (not as-configured) status of regulator, as a REGULATOR_STATUS value (or negative errno)
get_optimum_mode
- Get the most efficient operating mode for the regulator when running with the specified parameters.
set_load
- Set the load for the regulator.
set_bypass
- Set the regulator in bypass mode.
get_bypass
- Get the regulator bypass mode state.
set_suspend_voltage
- Set the voltage for the regulator when the system is suspended.
set_suspend_enable
- Mark the regulator as enabled when the system is suspended.
set_suspend_disable
- Mark the regulator as disabled when the system is suspended.
set_suspend_mode
- Set the operating mode for the regulator when the system is suspended.
set_pull_down
- Configure the regulator to pull down when the regulator is disabled.
Description
This struct describes regulator operations which can be implemented by regulator chip drivers.
-
struct
regulator_desc
¶ Static regulator descriptor
Definition
struct regulator_desc {
const char * name;
const char * supply_name;
const char * of_match;
const char * regulators_node;
int (* of_parse_cb) (struct device_node *,const struct regulator_desc *, struct regulator_config *);
int id;
unsigned int continuous_voltage_range:1;
unsigned n_voltages;
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 regulator_linear_range * linear_ranges;
int n_linear_ranges;
const unsigned int * volt_table;
unsigned int vsel_reg;
unsigned int vsel_mask;
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 enable_time;
unsigned int off_on_delay;
unsigned int (* of_map_mode) (unsigned int mode);
};
Members
name
- Identifying name for the regulator.
supply_name
- Identifying the regulator supply
of_match
- Name used to identify regulator in DT.
regulators_node
- Name of node containing regulator definitions in DT.
of_parse_cb
- Optional callback called only if of_match is present. Will be called for each regulator parsed from DT, during init_data parsing. The regulator_config passed as argument to the callback will be a copy of config passed to regulator_register, valid only for this particular call. Callback may freely change the config but it cannot store it for later usage. Callback should return 0 on success or negative ERRNO indicating failure.
id
- Numerical identifier for the regulator.
continuous_voltage_range
- Indicates if the regulator can set any voltage within constrains range.
n_voltages
- Number of selectors available for ops.:c:func:list_voltage().
ops
- Regulator operations table.
irq
- Interrupt number for the regulator.
type
- Indicates if the regulator is a voltage or current regulator.
owner
- Module providing the regulator, used for refcounting.
min_uV
- Voltage given by the lowest selector (if linear mapping)
uV_step
- Voltage increase with each selector (if linear mapping)
linear_min_sel
- Minimal selector for starting linear mapping
fixed_uV
- Fixed voltage of rails.
ramp_delay
- Time to settle down after voltage change (unit: uV/us)
min_dropout_uV
- The minimum dropout voltage this regulator can handle
linear_ranges
- A constant table of possible voltage ranges.
n_linear_ranges
- Number of entries in the linear_ranges table.
volt_table
- Voltage mapping table (if table based mapping)
vsel_reg
- Register for selector when using regulator_regmap_X_voltage_
vsel_mask
- Mask for register bitfield used for selector
csel_reg
- Register for TPS65218 LS3 current regulator
csel_mask
- Mask for TPS65218 LS3 current regulator
apply_reg
- Register for initiate voltage change on the output when using regulator_set_voltage_sel_regmap
apply_bit
- Register bitfield used for initiate voltage change on the output when using regulator_set_voltage_sel_regmap
enable_reg
- Register for control when using regmap enable/disable ops
enable_mask
- Mask for control when using regmap enable/disable ops
enable_val
- Enabling value for control when using regmap enable/disable ops
disable_val
- Disabling value for control when using regmap enable/disable ops
enable_is_inverted
- A flag to indicate set enable_mask bits to disable when using regulator_enable_regmap and friends APIs.
bypass_reg
- Register for control when using regmap set_bypass
bypass_mask
- Mask for control when using regmap set_bypass
bypass_val_on
- Enabling value for control when using regmap set_bypass
bypass_val_off
- Disabling value for control when using regmap set_bypass
active_discharge_on
- Disabling value for control when using regmap set_active_discharge
active_discharge_off
- Enabling value for control when using regmap set_active_discharge
active_discharge_mask
- Mask for control when using regmap set_active_discharge
active_discharge_reg
- Register for control when using regmap set_active_discharge
soft_start_reg
- Register for control when using regmap set_soft_start
soft_start_mask
- Mask for control when using regmap set_soft_start
soft_start_val_on
- Enabling value for control when using regmap set_soft_start
pull_down_reg
- Register for control when using regmap set_pull_down
pull_down_mask
- Mask for control when using regmap set_pull_down
pull_down_val_on
- Enabling value for control when using regmap set_pull_down
enable_time
- Time taken for initial enable of regulator (in uS).
off_on_delay
- guard time (in uS), before re-enabling a regulator
of_map_mode
- Maps a hardware mode defined in a DeviceTree to a standard mode
Description
Each regulator registered with the core is described with a structure of this type and a struct regulator_config. This structure contains the non-varying parts of the regulator description.
-
struct
regulator_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;
bool ena_gpio_initialized;
int ena_gpio;
unsigned int ena_gpio_invert:1;
unsigned int ena_gpio_flags;
};
Members
dev
- struct device for the regulator
init_data
- platform provided init data, passed through by driver
driver_data
- private regulator data
of_node
- OpenFirmware node to parse for device tree bindings (may be NULL).
regmap
- regmap to use for core regmap helpers if
dev_get_regmap()
is insufficient. ena_gpio_initialized
- GPIO controlling regulator enable was properly initialized, meaning that >= 0 is a valid gpio identifier and < 0 is a non existent gpio.
ena_gpio
- GPIO controlling regulator enable.
ena_gpio_invert
- Sense for GPIO enable control.
ena_gpio_flags
- Flags to use when calling
gpio_request_one()
Description
Each regulator registered with the core is described with a structure of this type and a struct regulator_desc. This structure contains the runtime variable parts of the regulator description.
-
struct regulator *
regulator_get
(struct device * dev, const char * id)¶ lookup and obtain a reference to a regulator.
Parameters
struct device * dev
- device for regulator “consumer”
const char * id
- Supply name or regulator ID.
Description
Returns a struct regulator corresponding to the regulator producer,
or IS_ERR()
condition containing errno.
Use of supply names configured via regulator_set_device_supply()
is
strongly encouraged. It is recommended that the supply name used
should match the name used for the supply and/or the relevant
device pins in the datasheet.
-
struct regulator *
regulator_get_exclusive
(struct device * dev, const char * id)¶ obtain exclusive access to a regulator.
Parameters
struct device * dev
- device for regulator “consumer”
const char * id
- Supply name or regulator ID.
Description
Returns a struct regulator corresponding to the regulator producer,
or IS_ERR()
condition containing errno. Other consumers will be
unable to obtain this regulator while this reference is held and the
use count for the regulator will be initialised to reflect the current
state of the regulator.
This is intended for use by consumers which cannot tolerate shared use of the regulator such as those which need to force the regulator off for correct operation of the hardware they are controlling.
Use of supply names configured via regulator_set_device_supply()
is
strongly encouraged. It is recommended that the supply name used
should match the name used for the supply and/or the relevant
device pins in the datasheet.
-
struct regulator *
regulator_get_optional
(struct device * dev, const char * id)¶ obtain optional access to a regulator.
Parameters
struct device * dev
- device for regulator “consumer”
const char * id
- Supply name or regulator ID.
Description
Returns a struct regulator corresponding to the regulator producer,
or IS_ERR()
condition containing errno.
This is intended for use by consumers for devices which can have
some supplies unconnected in normal use, such as some MMC devices.
It can allow the regulator core to provide stub supplies for other
supplies requested using normal regulator_get()
calls without
disrupting the operation of drivers that can handle absent
supplies.
Use of supply names configured via regulator_set_device_supply()
is
strongly encouraged. It is recommended that the supply name used
should match the name used for the supply and/or the relevant
device pins in the datasheet.
-
void
regulator_put
(struct regulator * regulator)¶ “free” the regulator source
Parameters
struct regulator * regulator
- regulator source
Note
drivers must ensure that all regulator_enable calls made on this regulator source are balanced by regulator_disable calls prior to calling this function.
-
int
regulator_register_supply_alias
(struct device * dev, const char * id, struct device * alias_dev, const char * alias_id)¶ Provide device alias for supply lookup
Parameters
struct device * dev
- device that will be given as the regulator “consumer”
const char * id
- Supply name or regulator ID
struct device * alias_dev
- device that should be used to lookup the supply
const char * alias_id
- Supply name or regulator ID that should be used to lookup the supply
Description
All lookups for id on dev will instead be conducted for alias_id on alias_dev.
Parameters
struct device * dev
- device that will be given as the regulator “consumer”
const char * id
- Supply name or regulator ID
Description
Remove a lookup alias if one exists for id on dev.
-
int
regulator_bulk_register_supply_alias
(struct device * dev, const char *const * id, struct device * alias_dev, const char *const * alias_id, int num_id)¶ register multiple aliases
Parameters
struct device * dev
- device that will be given as the regulator “consumer”
const char *const * id
- List of supply names or regulator IDs
struct device * alias_dev
- device that should be used to lookup the supply
const char *const * alias_id
- List of supply names or regulator IDs that should be used to lookup the supply
int num_id
- Number of aliases to register
Description
return 0 on success, an errno on failure.
This helper function allows drivers to register several supply aliases in one operation. If any of the aliases cannot be registered any aliases that were registered will be removed before returning to the caller.
-
void
regulator_bulk_unregister_supply_alias
(struct device * dev, const char *const * id, int num_id)¶ unregister multiple aliases
Parameters
struct device * dev
- device that will be given as the regulator “consumer”
const char *const * id
- List of supply names or regulator IDs
int num_id
- Number of aliases to unregister
Description
This helper function allows drivers to unregister several supply aliases in one operation.
-
int
regulator_enable
(struct regulator * regulator)¶ enable regulator output
Parameters
struct regulator * regulator
- regulator source
Description
Request that the regulator be enabled with the regulator output at
the predefined voltage or current value. Calls to regulator_enable()
must be balanced with calls to regulator_disable()
.
NOTE
the output value can be set by other drivers, boot loader or may be hardwired in the regulator.
-
int
regulator_disable
(struct regulator * regulator)¶ disable regulator output
Parameters
struct regulator * regulator
- regulator source
Description
Disable the regulator output voltage or current. Calls to
regulator_enable()
must be balanced with calls to
regulator_disable()
.
NOTE
this will only disable the regulator output if no other consumer devices have it enabled, the regulator device supports disabling and machine constraints permit this operation.
-
int
regulator_force_disable
(struct regulator * regulator)¶ force disable regulator output
Parameters
struct regulator * regulator
- regulator source
Description
Forcibly disable the regulator output voltage or current.
NOTE
this will disable the regulator output even if other consumer devices have it enabled. This should be used for situations when device damage will likely occur if the regulator is not disabled (e.g. over temp).
-
int
regulator_disable_deferred
(struct regulator * regulator, int ms)¶ disable regulator output with delay
Parameters
struct regulator * regulator
- regulator source
int ms
- miliseconds until the regulator is disabled
Description
Execute regulator_disable()
on the regulator after a delay. This
is intended for use with devices that require some time to quiesce.
NOTE
this will only disable the regulator output if no other consumer devices have it enabled, the regulator device supports disabling and machine constraints permit this operation.
-
int
regulator_is_enabled
(struct regulator * regulator)¶ is the regulator output enabled
Parameters
struct regulator * regulator
- regulator source
Description
Returns positive if the regulator driver backing the source/client has requested that the device be enabled, zero if it hasn’t, else a negative errno code.
Note that the device backing this regulator handle can have multiple
users, so it might be enabled even if regulator_enable()
was never
called for this particular source.
-
int
regulator_count_voltages
(struct regulator * regulator)¶ count
regulator_list_voltage()
selectors
Parameters
struct regulator * regulator
- regulator source
Description
Returns number of selectors, or negative errno. Selectors are numbered starting at zero, and typically correspond to bitfields in hardware registers.
-
int
regulator_list_voltage
(struct regulator * regulator, unsigned selector)¶ enumerate supported voltages
Parameters
struct regulator * regulator
- regulator source
unsigned selector
- identify voltage to list
Context
can sleep
Description
Returns a voltage that can be passed to regulator_set_voltage(), zero if this selector code can’t be used on this system, or a negative errno.
-
int
regulator_get_hardware_vsel_register
(struct regulator * regulator, unsigned * vsel_reg, unsigned * vsel_mask)¶ get the HW voltage selector register
Parameters
struct regulator * regulator
- regulator source
unsigned * vsel_reg
- voltage selector register, output parameter
unsigned * vsel_mask
- mask for voltage selector bitfield, output parameter
Description
Returns the hardware register offset and bitmask used for setting the regulator voltage. This might be useful when configuring voltage-scaling hardware or firmware that can make I2C requests behind the kernel’s back, for example.
On success, the output parameters vsel_reg and vsel_mask are filled in and 0 is returned, otherwise a negative errno is returned.
-
int
regulator_list_hardware_vsel
(struct regulator * regulator, unsigned selector)¶ get the HW-specific register value for a selector
Parameters
struct regulator * regulator
- regulator source
unsigned selector
- identify voltage to list
Description
Converts the selector to a hardware-specific voltage selector that can be directly written to the regulator registers. The address of the voltage register can be determined by calling regulator_get_hardware_vsel_register.
On error a negative errno is returned.
-
unsigned int
regulator_get_linear_step
(struct regulator * regulator)¶ return the voltage step size between VSEL values
Parameters
struct regulator * regulator
- regulator source
Description
Returns the voltage step size between VSEL values for linear regulators, or return 0 if the regulator isn’t a linear regulator.
-
int
regulator_is_supported_voltage
(struct regulator * regulator, int min_uV, int max_uV)¶ check if a voltage range can be supported
Parameters
struct regulator * regulator
- Regulator to check.
int min_uV
- Minimum required voltage in uV.
int max_uV
- Maximum required voltage in uV.
Description
Returns a boolean or a negative error code.
-
int
regulator_set_voltage
(struct regulator * regulator, int min_uV, int max_uV)¶ set regulator output voltage
Parameters
struct regulator * regulator
- regulator source
int min_uV
- Minimum required voltage in uV
int max_uV
- Maximum acceptable voltage in uV
Description
Sets a voltage regulator to the desired output voltage. This can be set during any regulator state. IOW, regulator can be disabled or enabled.
If the regulator is enabled then the voltage will change to the new value immediately otherwise if the regulator is disabled the regulator will output at the new voltage when enabled.
NOTE
If the regulator is shared between several devices then the lowest request voltage that meets the system constraints will be used. Regulator system constraints must be set for this regulator before calling this function otherwise this call will fail.
-
int
regulator_set_voltage_time
(struct regulator * regulator, int old_uV, int new_uV)¶ get raise/fall time
Parameters
struct regulator * regulator
- regulator source
int old_uV
- starting voltage in microvolts
int new_uV
- target voltage in microvolts
Description
Provided with the starting and ending voltage, this function attempts to calculate the time in microseconds required to rise or fall to this new voltage.
-
int
regulator_set_voltage_time_sel
(struct regulator_dev * rdev, unsigned int old_selector, unsigned int new_selector)¶ get raise/fall time
Parameters
struct regulator_dev * rdev
- regulator source device
unsigned int old_selector
- selector for starting voltage
unsigned int new_selector
- selector for target voltage
Description
Provided with the starting and target voltage selectors, this function returns time in microseconds required to rise or fall to this new voltage
Drivers providing ramp_delay in regulation_constraints can use this as their
set_voltage_time_sel()
operation.
-
int
regulator_sync_voltage
(struct regulator * regulator)¶ re-apply last regulator output voltage
Parameters
struct regulator * regulator
- regulator source
Description
Re-apply the last configured voltage. This is intended to be used where some external control source the consumer is cooperating with has caused the configured voltage to change.
-
int
regulator_get_voltage
(struct regulator * regulator)¶ get regulator output voltage
Parameters
struct regulator * regulator
- regulator source
Description
This returns the current regulator voltage in uV.
NOTE
If the regulator is disabled it will return the voltage value. This function should not be used to determine regulator state.
-
int
regulator_set_current_limit
(struct regulator * regulator, int min_uA, int max_uA)¶ set regulator output current limit
Parameters
struct regulator * regulator
- regulator source
int min_uA
- Minimum supported current in uA
int max_uA
- Maximum supported current in uA
Description
Sets current sink to the desired output current. This can be set during any regulator state. IOW, regulator can be disabled or enabled.
If the regulator is enabled then the current will change to the new value immediately otherwise if the regulator is disabled the regulator will output at the new current when enabled.
NOTE
Regulator system constraints must be set for this regulator before calling this function otherwise this call will fail.
-
int
regulator_get_current_limit
(struct regulator * regulator)¶ get regulator output current
Parameters
struct regulator * regulator
- regulator source
Description
This returns the current supplied by the specified current sink in uA.
NOTE
If the regulator is disabled it will return the current value. This function should not be used to determine regulator state.
-
int
regulator_set_mode
(struct regulator * regulator, unsigned int mode)¶ set regulator operating mode
Parameters
struct regulator * regulator
- regulator source
unsigned int mode
- operating mode - one of the REGULATOR_MODE constants
Description
Set regulator operating mode to increase regulator efficiency or improve regulation performance.
NOTE
Regulator system constraints must be set for this regulator before calling this function otherwise this call will fail.
-
unsigned int
regulator_get_mode
(struct regulator * regulator)¶ get regulator operating mode
Parameters
struct regulator * regulator
- regulator source
Description
Get the current regulator operating mode.
-
int
regulator_get_error_flags
(struct regulator * regulator, unsigned int * flags)¶ get regulator error information
Parameters
struct regulator * regulator
- regulator source
unsigned int * flags
- pointer to store error flags
Description
Get the current regulator error information.
-
int
regulator_set_load
(struct regulator * regulator, int uA_load)¶ set regulator load
Parameters
struct regulator * regulator
- regulator source
int uA_load
- load current
Description
Notifies the regulator core of a new device load. This is then used by DRMS (if enabled by constraints) to set the most efficient regulator operating mode for the new regulator loading.
Consumer devices notify their supply regulator of the maximum power they will require (can be taken from device datasheet in the power consumption tables) when they change operational status and hence power state. Examples of operational state changes that can affect power consumption 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 change to the most efficient operating mode if platform constraints allow.
On error a negative errno is returned.
-
int
regulator_allow_bypass
(struct regulator * regulator, bool enable)¶ allow the regulator to go into bypass mode
Parameters
struct regulator * regulator
- Regulator to configure
bool enable
- enable or disable bypass mode
Description
Allow the regulator to go into bypass mode if all other consumers for the regulator also enable bypass mode and the machine constraints allow this. Bypass mode means that the regulator is simply passing the input directly to the output with no regulation.
-
int
regulator_register_notifier
(struct regulator * regulator, struct notifier_block * nb)¶ register regulator event notifier
Parameters
struct regulator * regulator
- regulator source
struct notifier_block * nb
- notifier block
Description
Register notifier block to receive regulator events.
-
int
regulator_unregister_notifier
(struct regulator * regulator, struct notifier_block * nb)¶ unregister regulator event notifier
Parameters
struct regulator * regulator
- regulator source
struct notifier_block * nb
- notifier block
Description
Unregister regulator event notifier block.
-
int
regulator_bulk_get
(struct device * dev, int num_consumers, struct regulator_bulk_data * consumers)¶ get multiple regulator consumers
Parameters
struct device * dev
- Device to supply
int num_consumers
- Number of consumers to register
struct regulator_bulk_data * consumers
- Configuration of consumers; clients are stored here.
Description
return 0 on success, an errno on failure.
This helper function allows drivers to get several regulator consumers in one operation. If any of the regulators cannot be acquired then any regulators that were allocated will be freed before returning to the caller.
-
int
regulator_bulk_enable
(int num_consumers, struct regulator_bulk_data * consumers)¶ enable multiple regulator consumers
Parameters
int num_consumers
- Number of consumers
struct regulator_bulk_data * consumers
- Consumer data; clients are stored here. return 0 on success, an errno on failure
Description
This convenience API allows consumers to enable multiple regulator clients in a single API call. If any consumers cannot be enabled then any others that were enabled will be disabled again prior to return.
-
int
regulator_bulk_disable
(int num_consumers, struct regulator_bulk_data * consumers)¶ disable multiple regulator consumers
Parameters
int num_consumers
- Number of consumers
struct regulator_bulk_data * consumers
- Consumer data; clients are stored here. return 0 on success, an errno on failure
Description
This convenience API allows consumers to disable multiple regulator clients in a single API call. If any consumers cannot be disabled then any others that were disabled will be enabled again prior to return.
-
int
regulator_bulk_force_disable
(int num_consumers, struct regulator_bulk_data * consumers)¶ force disable multiple regulator consumers
Parameters
int num_consumers
- Number of consumers
struct regulator_bulk_data * consumers
- Consumer data; clients are stored here. return 0 on success, an errno on failure
Description
This convenience API allows consumers to forcibly disable multiple regulator clients in a single API call.
NOTE
This should be used for situations when device damage will likely occur if the regulators are not disabled (e.g. over temp). Although regulator_force_disable function call for some consumers can return error numbers, the function is called for all consumers.
-
void
regulator_bulk_free
(int num_consumers, struct regulator_bulk_data * consumers)¶ free multiple regulator consumers
Parameters
int num_consumers
- Number of consumers
struct regulator_bulk_data * consumers
- Consumer data; clients are stored here.
Description
This convenience API allows consumers to free multiple regulator clients in a single API call.
-
int
regulator_notifier_call_chain
(struct regulator_dev * rdev, unsigned long event, void * data)¶ call regulator event notifier
Parameters
struct regulator_dev * rdev
- regulator source
unsigned long event
- notifier block
void * data
- callback-specific data.
Description
Called by regulator drivers to notify clients a regulator event has occurred. We also notify regulator clients downstream. Note lock must be held by caller.
-
int
regulator_mode_to_status
(unsigned int mode)¶ convert a regulator mode into a status
Parameters
unsigned int mode
- Mode to convert
Description
Convert a regulator mode into a status.
-
struct regulator_dev *
regulator_register
(const struct regulator_desc * regulator_desc, const struct regulator_config * cfg)¶ register regulator
Parameters
const struct regulator_desc * regulator_desc
- regulator to register
const struct regulator_config * cfg
- runtime configuration for regulator
Description
Called by regulator drivers to register a regulator.
Returns a valid pointer to struct regulator_dev on success
or an ERR_PTR()
on error.
-
void
regulator_unregister
(struct regulator_dev * rdev)¶ unregister regulator
Parameters
struct regulator_dev * rdev
- regulator to unregister
Description
Called by regulator drivers to unregister a regulator.
-
int
regulator_suspend_prepare
(suspend_state_t state)¶ prepare regulators for system wide suspend
Parameters
suspend_state_t state
- system suspend state
Description
Configure each regulator with it’s suspend operating parameters for state. This will usually be called by machine suspend code prior to supending.
-
int
regulator_suspend_finish
(void)¶ resume regulators from system wide suspend
Parameters
void
- no arguments
Description
Turn on regulators that might be turned off by regulator_suspend_prepare and that should be turned on according to the regulators properties.
-
void
regulator_has_full_constraints
(void)¶ the system has fully specified constraints
Parameters
void
- no arguments
Description
Calling this function will cause the regulator API to disable all regulators which have a zero use count and don’t have an always_on constraint in a late_initcall.
The intention is that this will become the default behaviour in a future kernel release so users are encouraged to use this facility now.
-
void *
rdev_get_drvdata
(struct regulator_dev * rdev)¶ get rdev regulator driver data
Parameters
struct regulator_dev * rdev
- regulator
Description
Get rdev regulator driver private data. This call can be used in the regulator driver context.
-
void *
regulator_get_drvdata
(struct regulator * regulator)¶ get regulator driver data
Parameters
struct regulator * regulator
- regulator
Description
Get regulator driver private data. This call can be used in the consumer driver context when non API regulator specific functions need to be called.
-
void
regulator_set_drvdata
(struct regulator * regulator, void * data)¶ set regulator driver data
Parameters
struct regulator * regulator
- regulator
void * data
- data
-
int
rdev_get_id
(struct regulator_dev * rdev)¶ get regulator ID
Parameters
struct regulator_dev * rdev
- regulator