Am 12.12.2012 um 08:32 schrieb Gilles Chanteperdrix: > On 12/12/2012 07:54 AM, Michael Haberler wrote: > >> not strictly a Xenomai issue, but I'd completely bypass the kernel >> GPIO support and manipulate the GPIO registers directly - they are >> all memory mapped >> >> some inspiration here: >> http://git.mah.priv.at/gitweb/emc2-dev.git/blob/refs/heads/rtos-integration-preview1:/src/hal/drivers/hal_gpio.c >> >> this runs from a userland thread but kernel shouldnt be much >> different > > > Yeah, good idea, depending on the way to access registers, you get > concurrence issues, conflicts between applications, a lot of fun.
just to make sure I understand your suggestion: in kernel mode you'd suggest to go through gpiolib and use gpio_get_value/gpio_set_value if possible ? in user mode you can prepare things through sysfs but I dont see an alternative to memory-mapped register manipulation in that case if one wants to avoid system calls like read/write/open/ioctl which likely will be a dog on top of switching to secondary domain -m > > -- > Gilles. _______________________________________________ Xenomai mailing list [email protected] http://www.xenomai.org/mailman/listinfo/xenomai
