Thinking about it, this functionality would also be of use to James Peverill as part of his idea for in kernel real time control loops fully configurable from userspace. I've cc'd a few others involved in the original interfaces for setting up these maps. To take a random stab at how it might work. Every iio device gains some new interfaces iio_map_add iio_map_del These two take comma separated parameter lists to effectively fill a struct iio_map so iio_channel_name,client_device_name,client_channel_name (possibly other punctuation to make it clearer, also we would need to explicitly make the channel names available from userspace which is fine if tedious) Each of these effectively describes a single channel map and is one conceptual entity so fine as a sysfs attribute. Probably also need a means to list current maps that are set up, perhaps iio_map_list or similar (ugly: perhaps we can come up with a better way of describing them). This would then call iio_map_array_register (or a single element variant) to set up the maps. Now for currently un inserted client modules, these maps will be picked up on insertion just fine. The 'interesting' case would be for modules that are already there. We could define an appropriate callback to be notified of new entries that match the device name. Then the client will have to decide what to do about them. For example the iio to hwmon module would want to add more sysfs attributes for the new channels. So the questions are a) is there a better way? b) what types of driver do something similar already? c) would something like the above work? There is a clear use case for something with this functionality (several of them as it turns out) so let us work out how best to proceed. Jonathan On 01/17/2013 09:03 PM, Jonathan Cameron wrote: > > Good point. New use case for us so suggestions on how to do the association cleanly would be most welcome. Is there > anything similar out there? We could add a per iio device sysfs interface to add additional mappings but it is a little > uggly... > > -- > Sent from my Android phone with K-9 Mail. Please excuse my brevity. > > Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > On Wed, Jan 16, 2013 at 08:41:45AM +0000, Jonathan Cameron wrote: > > On 16/01/13 05:49, Guenter Roeck wrote: > > >On Sat, Nov 24, 2012 at 10:18:04AM +0000, Jonathan Cameron wrote: > > >>On 11/24/2012 05:27 AM, Guenter Roeck wrote: > > >>>Hi all, > > >>Hi Guenter, > > >>> > > >>>What would it take to move the MAX1363 driver out of staging ? > > >>> > > >>Nothing given it is already out of staging in linux-next (though only has been > > >>for about a week) > > >> > > >>>Background is that I need a hardware monitoring driver for MAX1139, and would > > >>>like to avoid using a driver from staging if possible (after all, it might > > >>>go away anytime). Another option would be to submit a hwmon driver for it, > > > >>>but that doesn't seem to be the best approach. > > >> > > >>The hwmon driver client driver for iio devices is still in staging, but mainly > > >>because I haven't had a chance to take a last look at it before posting it to > > >>the hmwon list. IIRC you were more or less happy with what went into staging > > >>in the first place, so hopefully not too much left to do. > > >> > > >Jonathan, > > > > > >can you educate me how to actually use iio_hwmon ? I get it loaded, > > >which registers the platform driver, but I have no idea how to instantiate it. > > > > > http://marc.info/?l=linux-iio&m=132933525705497&w=2 > > > > [PATCH 6/6] stargate2: example of map configuration for iio to hwmon > > example. > > > Hi Jonathan, > > In oth > er > words, I can not test it on a PC unless I write a driver to > instantiate it. Not too helpful :(. It means that iio drivers can not > be used / instantiated for hardware monitoring on PCs. > > Thanks, > Guenter > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
