GPS driver for Linux - kernel or user-space driver?

[Tim Bird <tim.bird@am.sony.com>]

I've been approached by a developer at Sony who wants to publish an
open source driver for a Sony GPS receiver module.

I've looked in the kernel source, and only see one standalone GPS
driver, for Garmin.  It appears that most GPS support in Linux is done
via user-space drivers.  Many GPS hardware modules appear to be
accessed via a serial line, or USB/serial port.  The Sony
module is pretty much the same, accepting commands and delivering
data via a uart from the chip.

I planning to recommend writing a user-space driver (based on
gpsd and/or the Android GPS HAL specification).  But I'm worried
I'm missing something.  Is this the correct approach, or is there
an established kernel API for GPS modules - such that I should
recommend that this developer writes a kernel module instead
of, or in addition to, the user-space support for the hardware?

Thanks,
 -- Tim

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Tim Bird
Architecture Group Chair, CE Workgroup of the Linux Foundation
Senior Staff Engineer, Sony Network Entertainment
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