Replicant

I'll track work on LTE modems on mainline kernel. The attached patch goes in the kernel. Build and install https://github.com/technexion-android/platform_external_libgpiod, then run the following script:

pin_name() {
    sed 's/-/ /' /sys/firmware/devicetree/base/soc/pinctrl@*/$1/samsung,pins
}

gpioset $(pin_name ap2mdm-soft-reset-n)=0
sleep .005
gpioset $(pin_name ap2mdm-soft-reset-n)=1
sleep .010
gpioset $(pin_name ap2mdm-status)=1

The modem should now appear in lsusb, in QDL mode. I am trying to figure out how to boot it. I'm using https://git.replicant.us/contrib/scintill/external_modem-boot/ with some obsolete pieces stripped out, but now the modem sends a non-existent command 0. I don't know why, but some guesses are that the HSIC is buggy in this kernel, or the old kernel does something I don't know about to get the modem in the right state.