I have a bricked device I’ll try it with. I bricked by accidently disconnecting while the SFOS image was flashing. That is, I already had VollaOS running on the phone. Assuming you mean the files from ~/.cache/ubports/vidofnir/firmware/unpacked/ ? There is no reason that shouldn’t work.
1 Like
Hmm, I should qualify that I believe I had it running. But now that I think of it, that was a very overly complicated day 
Still, I’ll give it a go before I send the device to a repair service
Thanks, I hope you have luck with de-bricking the device!
Since the missing-partition error interrupted my flashing progress, it could be a similar problem with both bricked devices.
Maybe a problem of GX4 vs. GX4 Pro? I think I read somewhere that @piggz works with a GX4 Pro and that Volla X23 is a GX4 Pro.
I think GX4 Pro has 128GB while GX4 has only 64GB. Maybe that makes a difference for the partition layout? So if you try to install Volla OS on a GX4 (without “Pro”) there might be some problem?
If you look at the pricing, I doubt it. The X23 is priced at the same price as the GX4 Pro (circa. 550 Euro). But I’ve not been able to find the Pro version from Gigaset on sale anywhere, so, who knows!
If you are from Germany, you could look at Voelkner, they have one on the market place for 485€ and I saw one directly from Voelkner for 435€ (possibly a customer return, don’t know) some time ago.
According to @piggz message in the Sailfish OS Fan Club on Telegram from September 19th:
EDIT: @Otto.de they offer one for 420€.
But more important:
- Volla X23: 6/128 GB
- GX4 Pro: 6/128 GB
- GX4: 4/64 GB
2 Likes
Hmmm. Neither the latest version of SP or GitHub - bkerler/mtkclient: MTK reverse engineering and flash tool support this ‘newer’ scatter file format. There is an issue in the bkerler repo which alludes to the the in progress nature of the issue: MT6789 da2 patching results in TypeError · Issue #758 · bkerler/mtkclient · GitHub
And EDIT, I don’t have the correct auh file since those don’t get circulated. Hmmm. Ah, mit SP v6 würde es gehen hätte man den richtigen auth file. den habe ich leider nicht.
EDIT: The available MediaTek Bypass tools seem to use a bug which was fixed in newer SOCs (like the MT6789 one used in X23/GX4 devices). Until now, I did not find a bypass tool made for MT6789 devices, but at XDA Forums, this topic seems to be actively discussed and ZG089 seems to currently work on finding something.
Yes, that’s the gist of the github link I posted. In any case, the SP flasher that works from linux is: SP_Flash_Tool_v6.2228_Linux I’ll poke around and see if I can dig up an auth file
Did the file indirectly linked by you (other issue at github, within rock.zip) work?
Else, the MTK Auth Bypass Tool seems to get enhanced for MT678* SOCs over time. With some luck, it will support the MT6789 in the future.
Another option - which looks experimental and was also indirectly linked by you - could be to try out MTK Client (bkerler/mtkclient on GitHub, see “Bypass SLA […]”).
Nope, but I didn’t even try that. The problem is the auth file needs to be the one that corresponds to the rom you’re trying to install. That will only be available from volla (and / or gigaset).
1 Like
I’D like to put a big fat “DON’T TRY THIS AT HOME” banner for the time being. Given that people are also having issues flashing Rephones (which I think is a non-issue) I don’t think you should try with Gigaset GX4/pro models until we have more info. I didn’t take enough notes while doing my testing and just assumed (not a bad assumption) that pulling the USB cable was the reason for all my woes. But, if I become uncertain about what steps I took and completed, you can be sure I wouldn’t trust my own output!
either way, if the X23 is actually the pro version this also would definitely explain the partition differences sonus experienced.
But can anyone enlighten me now, the GX4 / pro can be unlocked without problems and if so, how?
Or does it require it some kind of hack to root it first?
Hi Smirftsch,
Do you mean OEM unlocking to allow for installing a custom ROM (if there is any)?
⇒ This is possible by doing the usual steps (similar for many devices). Rooting the device is not needed.
From memory, these are the steps:
- go to Settings
- enable Developer Settings (tap 8× on the build number)
- go to developer settings (System → Developer)
- enable USB Debugging
- enable OEM unlock
- connect computer with installed ADB
- on phone accept debugging via this PC (I did check the option to always accept this PC.)
- on PC, type
adb devicesto check for okay connection (If no device is shown, repeat above steps and now miss none.) - on PC, type
adb reboot bootloader, then wait for the phone to reboot - on PC, type
fastboot devicesas checkup (as above with adb) - on PC, type
fastboot flashing unlockand within 5 seconds pressvolume upon the phone to enable flashing any ROM (like other official Android for the exact device, or, IF YOU KNOW THIS WILL PROBABLD BRICK (→ DESTROY) YOUR DEVICE any other ROM like Sailfish OS/VollaOS/Ubuntu Touch)
- on PC, type
fastboot reboot fastbootto reboot to fastbootd (If I understood it correctly,fastbootdis more modern, but less low level compared tobootloadermode. ⇒bootloaderfor OEM unlocking,fastbootfor fastbootd for actual flashing)
Is this what you asked for?
3 Likes
Yes, that was exactly what I was wondering about. Not every device/manufacturer allows that you know and I couldn’t find anything in the web if and how this may work with the Gigasets.
At the current stage however it seems indeed rather risky to me to try even although there seems to be no one so far who really has tried it with the pro version or did I miss something?
Either way, thanks a lot
If the GX4 and GX4Pro have different EMMC sizes, that would certainly be an issue, as I create the super partition specifically for the Pro size
The GX4 has 4GB RAM and 64GB storage whereas the Pro has 6GB and 128GB so, that seems a clear guide.
Interesting is that the rephone has the specs of the GX4 PRO where RAM and EMMC are concerned and flashing it causes no issues, aside from the fact that less of the available storage is used 
I’ve just seen that there are more PROs on the market and they’re not so expensive. But, I have to admit the rephone with same RAM and storage has a much nicer display than the GX4 Pro: 2340 x 1080 Pixel vs. 1560 x 720 Pixel . That’s visible pixel artifact territory. I also didn’t like the back cover which didn’t sit properly flush with the camera, but maybe that was an issue with one device. I’m not really inclined to go buy one, but then, as @piggz would say, I suffer from OCD
Based on “Load the Auth file for the device in the flash tool” in the List of SP Flash Tool errors & their solutions, the authorisation file seems to be device specific and not ROM specific.
In that forum, there are several seemingly interesting threads: 439 for error codes, 286 for unbricking how tos, …
Anyways, for the Gigaset GX4, I did not find anything that is really relevant here.
For some devices, there is a way to unbrick them:
Based on the UBports Forum, there is a professional company which seems to have the authorisation codes for some devices of the brands Gigaset and Volla.
- listed on their homepage: Gigaset GX4 / GX290 / GX290 Plus / …, Volla X / …
- not listed: Gigaset GX4 Plus/Pro, Volla X23
If someone does send some device to them, It would be nice to hear about the price tag for unbricking.