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What: /dev/wmi/dell-smbios
Date: November 2017
KernelVersion: 4.15
Perform SMBIOS calls on supported Dell machines.
through the Dell ACPI-WMI interface.
IOCTL's and buffer formats are defined in:
1) To perform an SMBIOS call from userspace, you'll need to
first determine the minimum size of the calling interface
buffer for your machine.
Platforms that contain larger buffers can return larger
objects from the system firmware.
Commonly this size is either 4k or 32k.
To determine the size of the buffer read() a u64 dword from
the WMI character device /dev/wmi/dell-smbios.
2) After you've determined the minimum size of the calling
interface buffer, you can allocate a structure that represents
the structure documented above.
3) In the 'length' object store the size of the buffer you
determined above and allocated.
4) In this buffer object, prepare as necessary for the SMBIOS
call you're interested in. Typically SMBIOS buffers have
"class", "select", and "input" defined to values that coincide
with the data you are interested in.
Documenting class/select/input values is outside of the scope
of this documentation. Check with the libsmbios project for
further documentation on these values.
6) Run the call by using ioctl() as described in the header.
7) The output will be returned in the buffer object.
8) Be sure to free up your allocated object.