DBus API — libratbag documentation

# DBus API

Note: the DBus interface is subject to change

Interfaces:

- org.freedesktop.ratbag1.Manager

- org.freedesktop.ratbag1.Device

- org.freedesktop.ratbag1.Profile

- org.freedesktop.ratbag1.Resolution

- org.freedesktop.ratbag1.Button

- org.freedesktop.ratbag1.Led

Changing settings on a device is a three-step process:

1. Change the various properties to the desired value

2. Invoke `org.freedesktop.ratbag1.Device.Commit()`

3. Optional: if an error occurred writing the new data to the device, a `org.freedesktop.ratbag1.Resync` signal is emitted on the device and all properties are updated accordingly.

The time it takes to write settings to a device varies greatly, any caller must be prepared to receive a `org.freedesktop.ratbag1.Device.Resync` signal several seconds after `org.freedesktop.ratbag1.Device.Commit()`.

## Notes on the DBus API

For easier debugging, objects paths are constructed from the device. e.g. `/org/freedesktop/ratbag/button/event5/p0/b10` is the button interface for button 10 on profile 0 on event5. The naming is subject to change. Do not rely on a constructed object path in your application.

### Types

Types used by these interfaces:

Type | Description
--- | ---
`b` | Bool
`o` | Object path
`s` | String
`u` | Unsigned 32-bit integer
`(uuu)` | A triplet of 32-bit integers
`ao` | Array of object paths
`as` | Array of strings
`au` | Array of 32-bit integers
`a(uu)` | Array of 2 32-bit integer tuples

For details on each type, see the DBus Specification.

### Flags

Properties marked as constant do not change for the lifetime of the object. Properties marked as mutable may change, and a `org.freedesktop.DBus.Properties.PropertyChanged` signal is sent for those unless otherwise specified.

## org.freedesktop.ratbag1.Manager

The org.freedesktop.ratbag1.Manager interface is the entry point to interact with ratbagd.

APIVersion
  Type:

    i

  Flags:

    read-only,constant

  The DBus API version. This is a stopgap feature while the DBus API is still in flux. The version has no backwards or forward-compatibility guarantees - your client must understand exactly the same version, it is not enough to support an older or a newer version.

  This API will be removed once the DBus API is declared stable.

Devices
  Type:

    ao

  Flags:

    read-only, mutable

  An array of read-only object paths referencing the available devices. The devices implement the org.freedesktop.ratbag1.Device interface.

## org.freedesktop.ratbag1.Device

The org.freedesktop.ratbag1.Device interface describes a single device known to ratbagd.

Model
  Type:

    s

  Flags:

    read-only, constant

  An ID identifying the physical device model. This string is guaranteed to be unique for a specific model and always identical for devices of that model.

  This is a string of one of the following formats:

  - `usb:1234:abcd:0`

  - `bluetooth:5678:ef01:0`

  - `unknown`

  In the future, other formats may get added. Clients must ignore unknown string formats.

  For a string starting with `usb:`, the format is the bus type (USB) followed by a 4-digit lowercase hex USB vendor ID, followed by a 4-digit lowercase hex USB product ID, followed by an decimal version number of unspecified length. These four elements are separated by a colon (`:`).

  For a string starting with `bluetooth:`, the format is the bus type (Bluetooth) followed by a 4-digit lowercase hex Bluetooth vendor ID, followed by a 4-digit lowercase hex Bluetooth product ID, followed by an decimal version number of unspecified length. These four elements are separated by a colon (`:`).

  For the string `unknown`, the model of the device cannot be determined. This is usually a bug in libratbag.

  For a `Model` of type `usb` and `bluetooth`, the version number is reserved for use by libratbag. Device with identical vendor and product IDs but different versions must be considered different devices. For example, the version may increase when a manufacturer re-uses USB Ids.

  Vendor or product IDs of 0 are valid IDs (e.g. used used by test devices).

Name
  Type:

    s

  Flags:

    read-only, constant

  The device’s name, suitable for presentation to the user.

FirmwareVersion
  Type:

    s

  Flags:

    read-only, constant

  A device-specific string with the firmware version, or the empty string. For devices with a major/minor or purely numeric firmware version, the conversion into a string is implementation-defined.

Profiles
  Type:

    ao

  Flags:

    read-only, mutable

  This property is mutable if the device supports adding and removing profiles.

  Provides the list of profile paths for all profiles on this device, see org.freedesktop.ratbag1.Profile

Commit() → ()

  Commits the changes to the device. This call always succeeds, the data is written to the device asynchronously. Where an error occurs, the `Resync()` signal is emitted and all properties are updated to the current state.

Resync()
  Type:

    Signal

  Emitted when an internal error occurs, usually on writing values to the device after `Commit()`. Upon receiving this signal, clients are expected to resync their property values with ratbagd.

## org.freedesktop.ratbag1.Profile

Index
  Type:

    u

  Flags:

    read-only, constant

  The zero-based index of this profile

Name
  Type:

    s

  Flags:

    read-write, mutable

  The name of this profile. If the name is the empty string, the profile name cannot be changed.

Disabled
  Type:

    b

  Flags:

    read-write, mutable

  True if this is the profile is disabled, false otherwise.

  Note that a disabled profile might not have correct bindings, so it’s a good thing to rebind everything before calling `Commit()`.

IsActive
  Type:

    b

  Flags:

    read-only, mutable

  True if this is the currently active profile, false otherwise.

  Profiles can only be set to active, but never to not active - at least one profile must be active at all times. This property is read-only, use the `SetActive()` method to activate a profile.

IsDirty
  Type:

    b

  Flags:

    read-only, mutable

  True if this profile is dirty, false otherwise.

  Dirty, that is, the device needs committing after being configured. This property becomes true whenever any other property of the profile is updated.

Resolutions
  Type:

    ao

  Flags:

    read-only, mutable

  This property is mutable if the device supports adding and removing resolutions.

  Provides the object paths of all resolutions in this profile, see org.freedesktop.ratbag1.Resolution.

Buttons
  Type:

    ao

  Flags:

    read-only, constant

  Provides the object paths of all buttons in this profile, see org.freedesktop.ratbag1.Button.

Leds
  Type:

    ao

  Flags:

    read-only, constant

  Provides the object paths of all LEDs in this profile, see org.freedesktop.ratbag1.Led.

AngleSnapping
  Type:

    i

  Flags:

    read-write, mutable

  Sensor angle snapping boolean value as an int (1 or 0), or -1 to indicate that the device doesn’t support reading and/or writing this value.

Debounce
  Type:

    i

  Flags:

    read-write, mutable

  Int for the button debounce time in milliseconds assigned to this profile. This time must be one of those listed in `Debounces`, or -1 to indicate that changing debounce time for this device is not allowed.

Debounces
  Type:

    au

  Flags:

    read-write, constant

  A list of permitted button debounce times. Values in this list may be used in the `Debounce` property. This list is always sorted ascending, the lowest debounce time is the first item in the list.

  This list may be empty if the device does not support reading and/or writing the debounce time.

ReportRate
  Type:

    u

  Flags:

    read-write, mutable

  uint for the report rate in Hz assigned to this profile. This rate must be one of those listed in `ReportRates`.

ReportRates
  Type:

    au

  Flags:

    read-write, constant

  A list of permitted report rates. Values in this list may be used in the `ReportRate` property. This list is always sorted ascending, the lowest report rate is the first item in the list.

  This list may be empty if the device does not support reading and/or writing the report rate.

SetActive() → ()

  Set this profile to be the active profile

## org.freedesktop.ratbag1.Resolution

Index
  Type:

    u

  Flags:

    read-only, constant

  Index of the resolution

Capabilities
  Type:

    au

  Flags:

    read-only, constant

  Bit-mask of capabilities.

  Value | Definition
  --- | ---
  1 | Resolution can be set for x and y axes separately.
  2 | Resolution can be disabled and enabled. Note that this capability only notes the general capability. A specific resolution may still fail to be disabled, e.g. when it is the active resolution on the device.

  (Source: `ratbag_resolution_capability` in libratbag.h).

  In the future, extra values may get added. Clients must ignore unknown Capabilities.

IsActive
  Type:

    b

  Flags:

    read-only, mutable

  True if this is the currently active resolution, false otherwise.

  Resolutions can only be set to active, but never to not active - at least one resolution must be active at all times. This property is read-only, use the `SetActive()` method to set a resolution as the active resolution.

IsDefault
  Type:

    b

  Flags:

    read-only, mutable

  True if this is the currently default resolution, false otherwise. If the device does not have the default resolution capability, this property is always false.

  Resolutions can only be set to default, but never to not default - at least one resolution must be default at all times. This property is read-only, use the `SetDefault()` method to set a resolution as the default resolution.

IsDisabled
  Type:

    b

  Flags:

    read-write, mutable

  True if this resolution is disabled, false otherwise. If the device does not have the disabled resolution capability, this property is always false.

Resolution
  Type:

    v

  Flags:

    read-write, mutable

  The resolution for this entry in dpi.

  If the variant is a single unsigned integer (`u`), the value is the resolution for both the x- and the y- axis.

  If the variant is a unsigned integer tuple (`(uu)`), the value is the resolution for the x- and y- axis separately.

  A client must leave the type intact, assigning a single `u` to a resolution object previously exporting `(uu)` is invalid.

  The value for the resolution must be equal to one of the values in `Resolutions`.

Resolutions
  Type:

    au

  Flags:

    read-only, constant

  A list of permitted resolutions. Values in this list may be used in the `Resolution` property. This list is always sorted ascending, the lowest resolution is the first item in the list.

  This list may be empty if the device does not support reading and/or writing to resolutions.

SetActive() → ()

  Set this resolution to be the active one

SetDefault() → ()

  Set this resolution to be the default

## org.freedesktop.ratbag1.Button

Index
  Type:

    u

  Flags:

    read-only, constant

  Index of the button

Mapping
  Type:

    (uv)

  Flags:

    read-write, mutable

  The current button mapping. The first element is the `ActionType` for this button and must be one of those in `ActionTypes`.

  If the ActionType is Button, the variant is an unsigned integer (`u`) denoting the button number to map to.

  If the ActionType is Special, the variant is an unsigned integer (`u`) denoting the special value to map to.

  If the ActionType is Macro, the variant is an array of integer tuples (`a(uu)`) where each tuple is `(type, keycode)` and the type is one of the following:

  Value | Description
  --- | ---
  0 | Key release event
  1 | Key press event

  If the ActionType is None, the variant is an unsigned integer (`u`) of value 0.

  If the ActionType is Unknown, the variant is an unsigned integer (`u`) of value 0.

ActionTypes
  Type:

    au

  Flags:

    read-only, constant

  Value | Name | Description
  --- | --- | ---
  0 | None | No mapping configured
  1 | Button | Mapping to a logical button number
  2 | Special | Mapping to a special function
  3 | Key | Mapping to a simple key action
  4 | Macro | Mapping to a macro key sequence
  1000 | Unknown | An unknown or unreadable mapping type

  See Special button functions for a list of supported special functions.

  Clients must ignore `ActionTypes` unknown to them.

## org.freedesktop.ratbag1.Led

Index
  Type:

    u

  Flags:

    read-only, constant

  Index of the LED

Mode
  Type:

    u

  Flags:

    read-write, mutable

  Enum describing the current mode, see `Modes`.

Modes
  Type:

    au

  Flags:

    read-only, constant

  A list of modes supported by this LED.

  Value | Definition
  --- | ---
  0 | LED is off
  1 | LED is on with constant brightness
  2 | LED cycles through a set of colors. This mode ignores the `Color` values.
  3 | LED uses a breathing-style animation

  In the future, extra values may get added. Clients must ignore unknown Modes.

Color
  Type:

    (uuu)

  Flags:

    read-write, mutable

  32-bit unsigned int triplet (RGB) of the LED’s color. Only the least significant bits are valid, the `ColorDepth` property defines the number of bits for each color. When writing to this property, all bits outside the color depth must be 0.

ColorDepth
  Type:

    u

  Flags:

    read-only, constant

  An enum specifying the color depth of this LED. Permitted values are:

  Value | Definition
  --- | ---
  0 | 0 bits per color (monochrome)
  1 | 8 bits per color
  2 | 1 bit per color

  In the future, extra values may get added. Clients must ignore unknown `ColorDepths` and not manipulate the LED color where the `ColorDepth` is unknown.

EffectDuration
  Type:

    u

  Flags:

    read-write, mutable

  The effect duration in ms, possible values are in the range 0 - 10000

Brightness
  Type:

    u

  Flags:

    read-write, mutable

  The brightness of the LED, normalized to the range 0-255, inclusive. Where the LED supports less than 8-bit of brightness, libratbag maps the value to a device-supported value in an implementation-defined manner.

## Special button functions

> All special button function values are based on the value `0x40000000` (`1 << 30`).

> Offset | Value | Description
> --- | --- | ---
> 0 | 0x40000000 | Unknown
> 1 | 0x40000001 | Doublelick
> 2 | 0x40000002 | Wheel left
> 3 | 0x40000003 | Wheel right
> 4 | 0x40000004 | Wheel up
> 5 | 0x40000005 | Wheel down
> 6 | 0x40000006 | Ratchet mode switch
> 7 | 0x40000007 | Resolution cycle up
> 8 | 0x40000008 | Resolution cycle down
> 9 | 0x40000009 | Resolution up
> 10 | 0x4000000a | Resolution down
> 11 | 0x4000000b | Resolution alternate
> 12 | 0x4000000c | Resolution default
> 13 | 0x4000000d | Profile cycle up
> 14 | 0x4000000e | Profile cycle down
> 15 | 0x4000000f | Profile up
> 16 | 0x40000010 | Profile down
> 17 | 0x40000011 | Second mode
> 18 | 0x40000012 | Battery level