On Sat, Apr 23, 2022 at 4:12 PM Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx> wrote: > On 4/23/22 00:50, Linus Walleij wrote: > > On Mon, Apr 18, 2022 at 1:19 PM Dmitry Osipenko > > <dmitry.osipenko@xxxxxxxxxxxxx> wrote: > > > >> What are the chances of seeing the kernel driver for BCM4751+? > > > > The kernel does not normally drive the GPS. The kernel has a small driver > > dealing with hardware power on/off of the GPS and exposing > > /dev/gnss0 to userspace. > > > > See Johans lecture at: > > https://events19.linuxfoundation.org/wp-content/uploads/2017/12/The-GNSS-Subsystem-Johan-Hovold-Hovold-Consulting-AB.pdf > > IIUC, driver also should be needed for the firmware uploading, similarly > to the BCM WiFi/BT chips, isn't it? As far as I can tell from the filesystem on this phone there is no firmware so it is flashed into the GPS chip. > > gpsd is the most common userspace daemon for GPS. > > gpsd will then talk to /dev/gnss0 as any other TTY IIUC. > > > > Replicant has a free implementation of the "MEIF" API for this GPS, > > I think what is needed is really for someone to pick up, polish and > > contribute that to gpsd > > https://git.replicant.us/contrib/PaulK/bcm4751/ > > My main curiosity is about whether you already have a working driver > prototype, something you could share with us all, so we could start > playing with it too :) It's on my TODO whenever there is time, but I have small kids so not so much time... I was hoping for the jolly people in postmarketOS to chime in because they seem to have a bunch of people with lots of time on their hands available :D Yours, Linus Walleij
