This brings the power on sequence in line with the EG25-G Hardware Design
datasheet, which states we need to wait at least 30 ms after VBAT becomes stable
before pulling PWRKEY low (first action of the power on sequene).
After this change the sequence becomes as follows:
- Set RESET_N high
- Wait 60 ms (double 30 ms)
- Execute PWRKEY sequence
60 ms was choosen because we don't know when VBAT becomes stable, but it should
be much less than an additional 30 ms. Empirical evidence suggests PinePhone
units with a healthy battery do not see serious side effects from not doing
this, while the modem will fail to boot and/or throw random errors on boot with
a worn out battery.
The AT commands list for each stage is now configured per-device, as
well as the UART port to be used.
As this list can be changed by the user, there is no more need for a
special GNSS-related option
The need to use libusb to check for the modem state on startup now
depends on a config option, instead of the device type. The USB PID and
VID are moved to config as well.
This commit prepares the use of device-specific configuration files.
These files should be named after the device-tree `compatible` string
with the `toml` extension.
`eg25-manager` will search for config files in
`<prefix>/etc/eg25-manager` first (or `/etc/eg25-manager` if prefix is
`/usr`), then in `<prefix>/share/eg25-manager`.
The EG25 modem needs at least 2 minutes after indicating 'RDY'
to be fully operational. If the modem is suspended before that,
calls or texts may not be seen by the userspace.
This mostly occurs when a full reboot or poweroff/poweron
sequence of the phone is performed.
:
Most of the modem issues follow a (incomplete) USB device reset. Instead
of relying solely on the existing timer, this patch adds a udev monitor
which resets the modem as soon as its associated USB device is reset,
which greatly improves recovery time.
This patch adds a 3s delay when resetting the modem during which we
avoid triggering a new reset. This makes sure we don't trigger a reset
twice in a row.
It also disables any related running timer to avoid being re-triggered
unnecessarily.
For some reason, during system the main loop exits before we call
g_main_loop_quit(), so don't rely on it and use a simple polling loop to
check for modem poweroff.
`Developer edition` phones have a different compatible string but should
be considered identical to BraveHeart edition here. Therefore BH is the
default phone, unless the compatible is that of a CE phone.
When powering off the modem, we must assert the RESET line only when the
modem has shut down (otherwise it'll cause a hard reset and won't allow
the modem to shut down properly).
This commit also polls the STATUS pin during poweroff and quits
immediately once this pin goes high.
