Add the driver for Gyro-ADC/speed-pulse interfaces found in Renesas R-Car SoCs.
Though being two separate devices, they have to be driven together because of
the shared start/stop register (located in Gyro-ADC still). At this time, only
speed-pulse interface is fully supported, the Gyro-ADC is just initialized and
started/stopped synchronously with the speed-pulse interface. A user interface
is implemented via several sysfs files which allow to read and reset the speed-
pulse interface's registers.
If you modify/create/remove sysfs files, you also have to document them
in Documentation/ABI/ which is missing from this patch.
Your sysfs files are also being created in a "racy" way, i.e. after
userspace is told about the device, please fix that as well.
And are you sure you want to control this through sysfs? There's no
other better user/kernel apis for it?
thanks,
greg k-h