Re: Weird Droid 4 modem protocol and a way to support it

[Denis Kenzior <denkenz@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 1532 bytes --]

Hi Pavel,

On 6/8/20 6:59 PM, Pavel Machek wrote:
> Hi!
> 
> I'd really like to get support for Droid 4 modem... unfortunately it
> is quite special. Few words about Droid 4 modem protocol:
> 

<snip>

> 
> I'm not sure what is the best way to support it. I was not able to get
> atchat.c to work with it (and I don't think it is quite suitable), so
> I ended up copying it and modifying it for Droid 4 protocol.
> 
> Is that acceptable? Can you see a better way?

I don't think there's really another way.  So the approach of duplicating 
GAtChat and everything inside drivers/atmodem is likely the way to go.

But if you pursue this, we really should throw out as much of the legacy in 
gatchat as possible:

- g_at_chat_suspend / resume is likely not needed (you're probably not running 
PPP over these, right)?
- stuff like g_at_chat_set_wakeup is only relevant for some weird modems and 
probably isn't relevant here
- add_terminator / blacklist_terminator might not be needed
- Some other concepts might not be needed, like send_pdu_listing and 
send_and_expect_short_prompt.  Those are really only for weird SMS commands.
- It might also be possible to greatly simplify the GAtParser concept.
- I'd also just put this all directly into drivers/motmodem/* instead of trying 
to extend gatchat library itself.

Most importantly though, we should stop using glib.  oFono is (glacially slowly) 
being ported over to ell.  So I don't really want to accept any new glib code.

Regards,
-Denis