@IanC
you are advicing him to beat a dead horse (or actually a not yet born horse...)
Ubus development started in 2011, while here we are talking about a really ancient proprietary OpenWrt vendor variant based on year 2010 sources (10.03)...
@sekhmet,
The answer is still pretty much the same, or put more bluntly: you are seeking for so a difficult task that if you need to ask help, you won't succeed.
You really need the vendor sources to be able to compile a fully compatible module. Otherwise you have no idea about the kernel options and compiler tweaks applied.
Surely someone wouldn't reply if they thought it was a waste of time: that is how the time is wasted.
For me this is a way to learn more about how things work, so I'm very happy to help OP explore options. The danger there is that they think I know more than I do, and I will end up wasting their time .
I agree this is a difficult challenge. But it's easy to imagine the device vendor did far more than they actually did. Maybe all the build options are stock. Some comparisons with what is in https://archive.openwrt.org/backfire/10.03/ for a few choice packages might help figure that out. Perhaps even seeing if binaries from there that would run.
Personally I would still recommend the new device route though .
...except that there is no (and has never been) bcm412l07 target in OpenWrt, so there aren't any target-specific default kernel options information available (except from the vendor...).
Typically each target include quite a lot of target-specific options that deviate from the "generic". E.g. year 2010 bcrm63xx (probably the closest to the vendor's bcm412l07) has approx. 200 lines of target specific kernel config options on top of the approx. 2700 generic kernel config options.
bcrm63xx switched to 2.6.32.x in Feb 2010, so the vendor has likely sticked to codebase older than that. But nobody knows, which date
Similarly, 2.6.30 is not enough for identifying the kernel exactly, as that is the "major" version in those times. You should know if it has been 2.6.30.10 or 2.6.30.15 or ...
(Current simpler Linux versioning has been there only since 3.0, since 2011)
Trying to guess, which exact OpenWrt codebase with which exact Linux version the vendor has been using as the basis, and how they have modified it (possibly also slightly bumping the kernel), is pretty futile.
Good luck for OP in that.
But let's not give him too much (=any) hope.
Thank you all for your time, I will try some kernel configuration and toolchains by changing some parameters and check if the ftdi_sio module works.
One last question: the kernel already has usbserial module, is it possible to read a ftdi serial cable without the use of the ftdi_sio module?
When I read it with "dd" command on linux, the output is always the same 50 bytes.
I'm not wasting my time, I'm asking somenthing for my interest and for the interest of others. If you think that it is a waste of time please, just don't answer. You have just wasted your time answering this post.
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