I would like to propose the following extension to the watchdog framework to allow userland programs access to the resolution of the watchdog timer should the hardware support such a feature. The first driver to make use of this feature would be the BCM Kona watchdog driver. I would also like to propose introducing a sysfs interface to the watchdog framework in a later phase of updating the watchdog framework. The sysfs interface would exist in addition to the existing ioctl interface. In the future, the ioctl interface could be deprecated in favour of the sysfs interface or both interfaces could be kept indefinitely. Phase 1: Add get resolution/set resolution ioctls. Add necessary flags and call-back functions. Extend bcm_kona_wdt.c to make use of the new functionality. Phase 2: Abstract the ioctl interface (into watchdog_ioctl.c) with a new set of per-driver ops, similar to what other frameworks are already doing. Phase 3: Introduce a sysfs interface (watchdog_sysfs.c) hooking into the already established per-driver ops. ioctl and sysfs calls would use the same framework and driver functions, requiring no code duplication. Please let me know if this sounds sensible or whether an alternate approach would be preferred. To give you an idea I am attaching an initial patch series for phase 1. Please keep in mind that the series is not meant to be applied as is. The code may need a bit more cleaning up. Also, I didn't add any documentation for the new features. Lastly, the series is currently only broken down into 2 patches (all framework changes and the actual driver changes), without further regard as to how this series may be applied. Patch 2/2 is dependent on the previous bcm_kona_wdt series: http://www.spinics.net/lists/linux-watchdog/msg03328.html Regards, -Markus Markus Mayer (2): watchdog: Add support to set timer resolution watchdog: bcm281xx: Support for timer resolution ioctls drivers/watchdog/bcm_kona_wdt.c | 57 +++++++++++++++++++++----------------- drivers/watchdog/watchdog_core.c | 14 ++++++++++ drivers/watchdog/watchdog_dev.c | 41 +++++++++++++++++++++++++++ include/linux/watchdog.h | 12 ++++++++ include/uapi/linux/watchdog.h | 3 ++ 5 files changed, 101 insertions(+), 26 deletions(-) -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
