On Mon, Aug 31, 2015 at 05:24:21PM +0100, Jonathan Cameron wrote: > On 31/08/15 17:01, Greg Wilson-Lindberg wrote: > > > > > >> -----Original Message----- > >> From: Michael Welling [mailto:mwelling79@xxxxxxxxx] On Behalf > >> Of Michael Welling > >> Sent: Friday, August 28, 2015 5:32 PM > >> To: Greg Wilson-Lindberg > >> Cc: linux-iio@xxxxxxxxxxxxxxx > >> Subject: Re: Adding MAX1363 to BBB > >> > >> On Fri, Aug 28, 2015 at 04:56:20PM -0700, Greg Wilson-Lindberg wrote: > >>> > >>> I've got the system running, but I get an invalid argument > >> error on the call to iio_buffer_refill(). I'm basically > >> using the same code as for the tsadc, just added in a fourth > >> channel, and none of the setup calls are returning errors, > >> but the first iio_buffer_refill() call returns an error. > >> I've dumped out the parameter that is being passed to the > >> iio_buffer_refill() call and it is the same as the value that > >> was returned from the iio_device_create_buffer() call. > >>> > >>> I've looked at the libiio source and I don't see anything > >> obvious that should return invalid argument for the > >> iio_buffer_refill() call. > >>> > >> > >> I believe that you need to register an interrupt for buffered > >> access to work. > >> > >> Do you have an interrupt connected and registered? > >> > > > > Nope, no interrupt. So I guess I would need to ask, how would I register the interrupt in the Device Tree? > The max1363 (and similar) don't have a dataready interrupt as they > are clocked of the actual clock cycles of the i2c transfers. So > they only read on demand. > Ah, yes. Looking at the datasheet the interrupt is triggered by a window comparator not end of sample. > > > > Or, alternatively, can I just get individual readings through IIO? > Either via sysfs, or by adding a sysfs trigger and poking that. > To add a sysfs trigger you'll need to probe the module, then poke > a number into the add_trigger attribute to create a trigger which can > then be associated with the max1363 (as normal). > > Then to 'fire' the trigger write to the trigger_now attribute of the > relevant trigger. > > Ideally Daniel will be back soonish with a final version of the > high resolution timer trigger that would also work well here. > (it's rather tied up with some configfs support which wis > trickier!). It is probably easiest to sample using sysfs directly. This would be same as the last method we tried while trying to access to TI ADC and touchscreen simultaneously. http://www.spinics.net/lists/linux-iio/msg20577.html > > Jonathan > > -- > > 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 > > > -- 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
