[fastrobot]

Originally Posted by davidfor

But, did you edit executable or configuration files? The latter might be generated at run time by something so we don't want them replaced. If there are executables that are not replaced by an upgrade, that to me is a concern. Or it means they are no longer being used.

I haven't checked all executables though I did chmod busybox, to make it suid root.
eg: Login, passwd, etc. won't work unless it's suid root.
I'm not concerned -- I just didn't want to say "full" upgrade, when it didn't wipe absolutely everything out on the partition and replace it.

The Glo and Aura HD are different hardware.

Mostly they have different wiring. The CPU has general purpose IO's, and from reading a diff of the Glo and Aura kenels, almost all the differences are in which io pin goes to what on the processor. Which mostly means the Engineer laying out the board found it too 'hard' to duplicate the pin assignments from one PCB to the next, or didn't care.

Pin assignments apparently can't be loaded as a kernel module; so basically Kobo was forced to compile the same kernel twice with different #defines for pin definitions.

They share some things, such as the CPU, but other elements are different enough that the upgrade package includes a separate kernel image for the Aura HD, but the Glo, N905C Touch and the Mini share one.

Right. That makes a lot of sense now that I've looked at the code.
Although, it's interesting to note that there are some code changes which look like bug fixes evident in the KoboAuraHD's version of the zforce-ir-touch driver, and in the epaper display driver (besides just macro definitions for the resolution change).

The hardware interface on those devices is essentially the same, so that the code didn't really need to change beyond setting a different screen resolution; but I'm guessing that historically, the Glo is an older device than the AuraHD and the engineers realized there were minor hardware problems based on what I see in the driver code.

I'm also noticing that the values sent to the Kobo Glo for frontlight illumination start much higher in the Glo than on the Aura. Considering it's the same MSP430 driving the frontlight, that makes me wonder if replacing the Glo's lighting table with the Aura's would allow me to dim the screen more. I'll have to experiment with that later when I'm not pressed for time.

Overall, it doesn't really look like KOBO has updated the kernels since the devices were released ; It's more of a test, once it's working and in production -- keep it that way....

You can't do a dd of the recovery partition to the root partition as there is code to execute the reinstall. You would need to remove that afterwards. In any case, the factory reset does install a copy of the uBoot and kernel. And everything else.

OK. Although it's not impossible to do a dd in general, the way Kobo wrote the script is perhaps not intelligent enough to detect by an 'if' statement which partition it is running from and behave accordingly -- but OK, it's more important to understand what they did than what they could have done.

But taking a copy of the SD card will save you if you make a mistake.

Yep. DId that... cloned to my hard drive. Probably should back up the hard drive too, and put a copy of it in a bank vault somewhere... but I'm lazy. It might be cheaper to buy a second KoboAuraHD.

And before you say anything, the quality of the commit comment is on par with just about any place I've worked.

I think there's a Dilbert cartoon about that... eg: You must be in management, .... You must be in Engineering ... because ....

Yes, it would have been very good if their crystal ball had told them that they would need multiple versions of this and exactly what they would need to call them.

I'm probably ignorant about how the web browser interface works for git.

Is there no way to rename a directory after the fact, or show a history of what it was named (in the past) by clicking it somehow, or add a symlink directory once management had come up with a name for what engineering did, and decided to sell it on the market? I know second guessing management is impossible, but once they committed....!

I don't expect to change Kobo's middle of the road programming approach ; I'm just curious about the git interface as I'm not doing very well with it in the school of hard knocks.

So I want to be sure and jsay for spending the time to get me up to speed on where most things are not stored by crushing my misconceptions. Especially since the labels aren't always very helpful. I always try and remember that "Organic" is part of the word "organization" -- it's all about how things grow. And sometimes that means the only one who remembers where something is, is someone who has already been there for a long time. I appreciate it.