On 10/05/2013 11:18 AM, leroy christophe wrote: > > Le 05/10/2013 10:41, Lars-Peter Clausen a écrit : >> On 10/05/2013 10:21 AM, Christophe Leroy wrote: >>> + .consumer_channel = "channel_0", >>> + .adc_channel_label = "0", >>> + }, >>> + { >>> + .consumer_dev_name = AD7923_NAME, >>> + .consumer_channel = "channel_1", >>> + .adc_channel_label = "1", >>> + }, >>> + { >>> + .consumer_dev_name = AD7923_NAME, >>> + .consumer_channel = "channel_2", >>> + .adc_channel_label = "2", >>> + }, >>> + { >>> + .consumer_dev_name = AD7923_NAME, >>> + .consumer_channel = "channel_3", >>> + .adc_channel_label = "3", >>> + }, >>> + { } >>> +}; >> This is a mapping between channel names of the provider between the channel >> names of the consumer. So it is specific to a certain combination of >> consumer and provider and usually depend on how things are physically wired >> on your board. As such there can be no generic mapping and this needs to go >> into your machine/board driver. The mapping is usually passed to the IIO >> driver via its platform data. >> >> So e.g. imagine you have a provider like this driver and you have a consumer >> that has a "voltage" channel. And on your board channel 3 of the ADC is what >> you want to route to that consumer. Then your mapping would look like this: >> >> { >> .consumer_dev_name = "your_consumer_device.1", >> .consumer_channel = "voltage", >> .adc_channel_label = "AIN3", >> } >> >> And in your consumer driver you'd do: >> >> channel = iio_channel_get(dev, "voltage"); >> >> > Thanks for the explanation. > > Can the mapping be retrieved via of_platform ? > > Indeed, the only exemple I found was in the lp8788_adc driver, which > includes iio/machine.h and declares a default mapping, but it is based on > platform_data, not of_platform. > If you are using device tree you can specify the mapping inside the devicetree. Have a look at Documentation/devicetree/bindings/iio/iio-bindings.txt - Lars -- 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