On Thursday, July 25, 2013 7:18 AM, Ian Abbott wrote: > On 2013-07-24 20:14, H Hartley Sweeten wrote: >> Make the built-on dio subdevice 0 and the three add-on modules >> subdevices 1-3. This allows the driver to consistently use the >> ii20k_module_iobase() helper to get the base address needed to >> access a the registers used by a given subdevice. >> >> Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx> >> Cc: Ian Abbott <abbotti@xxxxxxxxx> >> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > It's best to avoid reordering the subdevices if you can help it to avoid > screwing with userspace unnecessarily. This one can be dropped. It was added last just to make the 'iobase' use consistent. But... Shouldn't the userspace be getting the subdevice using comedi_find_subdevice_by_type()? Or can userspace directly access a subdevice based on the index? The original order was: 0 - AO or AI subdevice (module 1) 1 - AO or AI subdevice (module 2) 2 - AO or AI subdevice (module 3) 3 - DIO subdevice (built-in module) The new order is: 0 - DIO subdevice (built-in module) 1 - AO or AI subdevice (module 1) 2 - AO or AI subdevice (module 2) 3 - AO or AI subdevice (module 3) So logically the add-on modules are still in the same order. So the first call of comedi_find_subdevice_by_type() to find the AO or AI subdevice will still return the module 1 subdevice, second will return module 2, and third will return module 3. I see no functional change in the userspace interaction. Thanks, Hartley _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
