On Thursday, January 26, 2017 at 12:08:17 AM UTC-6, Drew Fustini wrote: > I get a Segmentation Fault when I read the position: > > It appears to occur in: > (eqep_get_position [tieqep]) from [<c08930d0>] (dev_attr_show+0x2c/0x58)
I've experimenting more with this eQEP error on the 4.9 kernel: https://gist.github.com/pdp7/fe07082d23f2bfbc362c733a7b0aea72 >From drivers/misc/tieqep.c at found in this patch: https://github.com/RobertCNelson/ti-linux-kernel-dev/tree/ti-linux-4.9.y/patches/drivers/ti/eqep This readl() runs OK in eqep_probe(): https://github.com/RobertCNelson/ti-linux-kernel-dev/tree/ti-linux-4.9.y/patches/drivers/ti/eqep#L401 Line 697: dev_info(&pdev->dev, "QPOSCNT:0x%08x\n", readl(eqep->mmio_base + QPOSCNT)); But the same readl() causes a seg fault in eqep_get_position(): https://github.com/RobertCNelson/ti-linux-kernel-dev/tree/ti-linux-4.9.y/patches/drivers/ti/eqep#L401 Line 401: position = readl(eqep->mmio_base + QPOSCNT); I'm not sure what the difference is. Maybe the memory mapping changes in between the probe and reading the sysfs file? Any ideas? thanks, drew -- 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/dfbe95de-1176-41b0-b45d-054cd9bae991%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
