On 02/07/2013 02:09 AM, Linus Walleij wrote: > On Thu, Feb 7, 2013 at 1:58 AM, Darren Hart <dvh...@linux.intel.com> wrote: > >> Is it that some other driver has claimed these GPIO lines? If so, how do >> I determine which one? > > Yes I think that could be it, the driver would need to call > gpio_export() for it to also be accessible in sysfs.
Do you mean gpiochip_export()? Hrm, neither gpio-pch nor gpio-sch call gpiochip_export() directly. They both call gpiochip_add() and that calls gpiochip_export() unconditionally. As far as I could tell, both drivers call gpiochip_export(). I thought maybe the sch happened to early, maybe hitting the the pre-driver-model-support note in gpiochip_export(), but it runs after the pch chip for some reason, and that one is fine. I suppose I could be failing on device_create or sysfs_create_group and just not seeing the output. I'll try to get DYNAMIC_DEBUG and pr_debug in gpiolib.c working (that always seems to be an unnecessarily arduous exercise). > > Configure in debugfs and check the file "gpio" in debugfs > to figure out the client. That file contained only the gpiochip244 from the gpio-pch driver, nothing from the sch. Thanks! -- Darren Hart Intel Open Source Technology Center Yocto Project - Technical Lead - Linux Kernel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
