On Wed, Apr 25, 2018 at 08:26:59AM +0200, Pavel Machek wrote: > Hi! > > > This series adds a new subsystem for GNSS receivers (e.g. GPS > > receivers). > > > > While GNSS receivers are typically accessed using a UART interface they > > often also support other I/O interfaces such as I2C, SPI and USB, while > > yet other devices use iomem or even some form of remote-processor > > messaging (rpmsg). > > > > The new GNSS subsystem abstracts the underlying interface and provides a > > new "gnss" class type, which exposes a character-device interface (e.g. > > /dev/gnss0) to user space. This allows GNSS receivers to have a > > representation in the Linux device model, something which is important > > not least for power management purposes and which also allows for easy > > detection and (eventually) identification of GNSS devices. > > Actually... no, what you done is not GNSS subsystem. It is generic > subsystem for a link + some controls, typically for power. > > Yes, that setup is common for GPS receivers, but it is there also for > modems (droid 4: usb + gpios) and bluetooth dongles (n900: serial + > gpios). Those would be handled by other subsystems. The idea here is that eventually there may be more GNSS specific bits added, such as 1PPS support that I already mentioned. If someone is crazy enough to put a location service in the kernel with a more high-level interface (an in-kernel gpsd) they can try, but I'm more and more convinced that needs to remain in user space. I did also already mentioned however, that some hybrid approach may be doable, such as handling port setup over NMEA/UBX/SiRF from within the kernel. Johan -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
