On Wed, 2010-10-06 at 14:23 -0400, Paul Thomas wrote: > On Wed, Oct 6, 2010 at 11:24 AM, Jonathan Cameron <jic23@xxxxxxxxx> wrote: > > On 10/06/10 19:13, Paul Thomas wrote: > >> I'm planning a rev of the ads7871 driver. I want to add in the ability > >> to set the gain on the chip as well as do differential reads. To do > >> this I'm adding a bunch of SENSOR_DEVICE_ATTR lines. Awhile ago I had > >> got a suggestion from Jonathan to use a local macro for these > >> statements. Would that be a macro that looped through calling the > >> other macro 8 times with values 0-7? Could someone point me to an > >> example where this is used? > > I suspect I meant something like > > > > #define ADS7871_VOLTAGE_ATTR(n) SENSOR_DEVICE_ATTR(in##n##_input, S_IRUGO, show_voltage, NULL, n); > > But looking back at the usage, it really is a matter of taste, and I'm > > not sure my suggestion was a good one in this case! > > > > Jonathan > > > > OK, it's not much to just put in all the lines. So I'm adding > attributes inX_gain and inX_diff for each of the 8 channels. The diff > option sets whether it's a differential read or a single ended read to > ground. > Since you plan to amend the ABI, it might make sense to discuss the proposed attributes and their usage first. I would assume that hardware monitoring sensors have a static gain, ie a gain which does not have to be set during runtime, but is fixed for a specific board. I don't know about the diff attribute, but it also seems to be a board option, not a runtime option. For such parameters, it might make more sense to define a common hwmon platform parameter structure and expect it to be set during board initialization. Works quite nicely for other drivers. Thanks, Guenter _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
