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+What: /dev/wmi/dell-smbios
+Date: November 2017
+KernelVersion: 4.15
+Contact: Dell.Client.Kernel@dell.com
+Description:
+ Perform SMBIOS calls on supported Dell machines.
+ through the Dell ACPI-WMI interface.
+
+ IOCTL's and buffer formats are defined in:
+ <uapi/linux/wmi.h>
+
+ 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.