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IOCTL_LAMP_GET_CAPABILITIES_WHITE IOCTL (lamp.h)

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The IOCTL_LAMP_GET_CAPABILITIES_WHITE control code queries the capabilities of the lamp when the device is configured to emit white light.

#define IOCTL_LAMP_GET_CAPABILITIES_WHITE \
    CTL_CODE(IOCTL_LAMP_BASE, 0x0000, METHOD_BUFFERED, FILE_ANY_ACCESS)

Major code

IRP_MJ_DEVICE_CONTROL

Input buffer

Irp->AssociatedIrp.SystemBuffer points to a buffer of type LAMP_CAPABILITIES_WHITE.

Input buffer length

Length of the buffer.

Output buffer

Irp->AssociatedIrp.SystemBuffer is filled with all capabilities supported by the lamp hardware.

Output buffer length

IO_STACK_LOCATION.Parameters.DeviceIoControl.OutputBufferLength is the length of the buffer (in bytes) passed in the Irp->AssociatedIrp.SystemBuffer field.

Status block

The driver sets Irp->IoStatus.Status to STATUS_SUCCESS or the appropriate error status. It will set Irp->IoStatus.Information to the number of bytes required to hold the buffer.

Remarks

By requirement, a lamp whose driver supports the GUID_DEVINTERFACE_LAMP interface is required to support emitting white light.

The payload of this IOCTL is a LAMP_CAPABILITIES_WHITE structure.

The IsLightIntensityAdjustable field indicates whether the luminance level can be programmed. If this field evaluates to FALSE, it means that the underlying device only supports the on/off switch and the light intensity cannot be adjusted.

Requirements

Requirement Value
Header lamp.h