Am Donnerstag, 5. Mai 2011, 12:01:25 schrieb Jonathan Cameron: > On 05/05/11 10:44, Alexander Stein wrote: > > Am Donnerstag, 5. Mai 2011, 11:08:18 schrieb Jonathan Cameron: > >> On 05/05/11 09:32, Alexander Stein wrote: > >>> Just set vref_mv in your platform config to use external vref. > >>> Otherwise the internal one is used. > >> > >> Would be nicer to see this done with the regulator framework. But then > >> if you have a use case on a board where that isn't available, then fair > >> enough. > > > > Well, for the regulator framework I would redesign the driver a bit. > > Currently the analogue inputs are displayed as mV in sysfs. If the > > current analogue input voltage is shown via the regulator framework the > > ads7846 driver itself can shows the actual ADC values. The latter ones > > don't need to know the reference voltage. > > But I think this is a different problem than choosing the reference > > voltage for an ADC for what this patch is for. > > I'm somewhat confused by what you mean here. The regulator framework is > all about power supplies. This device would merely be a consumer that > asks for what (if anything) is being uspplied to the external vref line. > Basically it's a more general alternative to supplying the value via > platform data. Maybe I did get you wrong. I thought you meant retrieving the voltage at the analogue input somehow using the regulator framework. I don't know much about this framework, so how can you handle this: The external vref is board-specific, e.g. hard-wired to 3,3V? There is no regulator which could adjust the voltage attached to ext vref. Alexander -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
