Bill, Bill Gatliff <b...@billgatliff.com> wrote on 01/27/2012 10:42:57 AM:
> > On Fri, Jan 27, 2012 at 5:31 AM, <bruce_leon...@selinc.com> wrote: > > > > The problem is we've got a number of other things hooked up to the GPIO > > pins that it would be very bad if someone from user space played with > > them, like our FPGA configuration pin. Some one toggles that and our box > > goes stupid. So what I'm wondering is if there's a way, preferably via > > the device tree, to limit the GPIOs that GPIO Lib exposes to user space? > > Sounds like you DON'T want to merely export that GPIO pin to userspace. > Well, yes I do want to just export to userspace, I just want to restrict the pins that get exported to only those that are defined in the device tree. I don't want or need to access any of the exported pins from kernel space and I don't want user space to access any pin not explicitly called out in the device tree. I want it to behave like gpio-leds only with input as well as output capabilities. > If you have anything in kernel space doing a gpio_request() on that > pin, it won't be exportable to userspace anyway. Regardless, you are > probably better off implement a DEVICE_ATTR that, in its store() > method, treads lightly on said pin. And then do a gpio_request() in > kernel space so that users can't ever see the pin directly. > > Just my $0.02. > If I understand this correctly you're basically saying that gpiolib is a waste of time and I should just write my own driver? Bruce _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev