Thinking a little about what your requirement, it would by simple to modify these parameters in BB-ADC driver via sysfs. Think of the DT as default parameters when the driver first starts.
Regards, John > On Mar 3, 2016, at 12:41 AM, TJF <jeli.freih...@gmail.com> wrote: > > Hi John! > > Thanks for the dts examples. > > Lets say I want to develop a simple osziloscop application and the user > should be able to choose the sampling rate or the number of channels. > Therefor changing the device tree overlay is necessary, right? And since > unloading an overlay is unsave in some kernel versions, the application has > to reboot? > > That's anoying. One spends a lot of time to find and test a kernel feature, > just to find out that it's unuseable for most practical purposes. > > BR > > Am Donnerstag, 3. März 2016 07:56:21 UTC+1 schrieb john3909: > /* > * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/ > <http://www.ti.com/> > * > * This program is free software; you can redistribute it and/or modify > * it under the terms of the GNU General Public License version 2 as > * published by the Free Software Foundation. > */ > /dts-v1/; > /plugin/; > > / { > compatible = "ti,beaglebone", "ti,beaglebone-black", > "ti,beaglebone-green"; > > /* identification */ > part-number = "BB-ADC"; > version = "00A0"; > > /* state the resources this cape uses */ > exclusive-use = > /* the pin header uses */ > "P9.31", /* AIN0 */ > "P9.40", /* AIN1 */ > "P9.37", /* AIN2 */ > "P9.38", /* AIN3 */ > "P9.33", /* AIN4 */ > "P9.36", /* AIN5 */ > "P9.35", /* AIN6 */ > /* the hardware ip uses */ > "tscadc"; > > fragment@0 { > target = <&tscadc>; > __overlay__ { > > status = "okay"; > adc { > ti,adc-channels = <0 1 2 3 4 5 6>; > ti,chan-step-avg = <0x1 0x1 0x1 0x1 0x1 0x1 > 0x1>; > ti,chan-step-opendelay = <0x98 0x98 0x98 0x98 > 0x98 0x98 0x98>; > ti,chan-step-sampledelay = <0x0 0x0 0x0 0x0 0x0 > 0x0 0x0>; > }; > }; > }; > }; > > So the speed is selected by changing the number of samples in averaging and > the open delay and sample delay. > > Regards, > John > > > > >> On Mar 2, 2016, at 10:52 PM, TJF <jeli.f...@ <>gmail.com >> <http://gmail.com/>> wrote: >> >> Hi John! >> >> Am Donnerstag, 3. März 2016 00:07:02 UTC+1 schrieb john3909: >> For example, do: >> >> dd if=/dev/iio:device0 of=~/test >> >> Enable the iio buffer and your file will receive samples at the configured >> speed. >> >> Thanks for your statement. An interesting solution, I didn't find that yet. >> >> From my point of view this is a big issue for BB[WBG?]. Most of the IO >> kernel features are badly documented. For a kernel novice, features are >> hard to find and >> hard to understand. (Especially for non-native speakers.) >> One or more examples in each documentation would help a lot, like the one >> you posted here (How to configure speed? How to set up step configurations? >> Does it solve the iio miss-sampling issue, appearing at multi channel >> sampling in single mode?). >> >> Anyway, my prefered solution is still libpruio since it >> doesn't load the ARM CPU >> offers a lot of further features (ie. scaling for 13 to 16 bit or triggering >> the measurement start by up to four events) >> can act in concert with the other PRU (important for hard real-time >> requirements > 10 kHz). >> BR >> >> -- >> For more options, visit http://beagleboard.org/discuss >> <http://beagleboard.org/discuss> >> --- >> You received this message because you are subscribed to the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to beagleboard...@ <>googlegroups.com <http://googlegroups.com/>. >> For more options, visit https://groups.google.com/d/optout >> <https://groups.google.com/d/optout>. > > > -- > For more options, visit http://beagleboard.org/discuss > <http://beagleboard.org/discuss> > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to beagleboard+unsubscr...@googlegroups.com > <mailto:beagleboard+unsubscr...@googlegroups.com>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.