@Mark, Yes,and no.
No, in that there is no way to differentiate which header the peripheral is physically attacked to. Yes, in that device tree "defines" usually define a device module as something similar to: device_tree_friendly_name@<peripheral module base address> In other words, we should be able to extrapolate which device module, and pins are used based on their base address. There is also a place in a systems directory structure that sysfs uses the base address as part of the path for the device . . .but I can not recall exactly where that is :/ On Mon, Feb 8, 2016 at 4:56 PM, Mark A. Yoder <[email protected]> wrote: > Well, they move around depending on which dts you boot under. P9_14 > appears at /sys/class/pwm/pwmchip*2*/pwm0 with > *cat $SLOTS * > 0: PF---- -1 > 1: PF---- -1 > 2: PF---- -1 > 3: PF---- -1 > 4: P-O-L- 0 Override Board Name,00A0,Override Manuf,*univ-emmc* > > But if you use: > *cat $SLOTS * > 0: PF---- -1 > 1: PF---- -1 > 2: PF---- -1 > 3: PF---- -1 > 4: P-O-L- 0 Override Board Name,00A0,Override Manuf,*cape-universaln* > > it appears at /sys/class/pwm/pwmchip*4*/pwm0! > > Is there a way the pwm system can tell you which headers they are attached > to? > > --Mark > > On Monday, February 8, 2016 at 6:42:11 PM UTC-5, RobertCNelson wrote: >> >> On Mon, Feb 8, 2016 at 5:36 PM, Mark A. Yoder <[email protected]> >> wrote: >> > Well.... /sys/class/pwm/pwmchip2/pwm0 worked! Thanks... >> > >> > So given the pin name (P9_14 for example) how do I find the pwm path? >> (I'm >> > trying to port bonescript to Jessie.) >> >> For the pwm, I think it's load order (scary).... not sure if we can >> for an alias in the dt.. >> >> Regards, >> >> -- >> Robert Nelson >> https://rcn-ee.com/ >> > -- > 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 [email protected]. > For more options, visit 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 [email protected]. For more options, visit https://groups.google.com/d/optout.
