Wrong answer. No, it is not reversed.
Originally Posted by knc1
If the command you used is "as posted" and not a typo here -
Then your source (InFile, if= ) and destination (OutFile, of= ) options are reversed.
The command "as posted" is reading from the mmc not writing to it.
That command is used to make a backup copy of the kernel. You flash the kernels with fastboot. Your advice to reverse those options is actually DANGEROUS because it could actually damage data stored in the mmc, such as the device PCBSN, which would require ANOTHER custom uboot to debrick it...
Although it *might* be possible to use dd to write a kernel image into a portion of /dev/mmcblk0 (with the correct dd seek offset), that is not a *normal* way to do this, and it would require testing and verification. Because it is a device, it might not support the dd "seek" option needed to do that, and that area of mmc might be protected from writing by the kernel mode device drivers...