On 02/13/2016 03:14 PM, Jonathan Cameron wrote: > On 11/02/16 10:04, Gregor Boirie wrote: >> Adds a new per-device sysfs attribute "clockid" to allow userspace to select a >> particular POSIX clock for buffered samples and events timestamping. >> >> When read, the attribute file returns a stringifi'ed clockid_t matching the >> currently selected clock. >> Writing a stringifi'ed clockid_t to the attribute file will select the >> corresponding clock for the device. >> >> Following clocks, as listed in clock_gettime(2), are supported: CLOCK_REALTIME, >> CLOCK_MONOTONIC, CLOCK_MONOTONIC_RAW, CLOCK_REALTIME_COARSE, >> CLOCK_MONOTONIC_COARSE, CLOCK_BOOTTIME and CLOCK_TAI. >> >> Signed-off-by: Gregor Boirie <gregor.boirie@xxxxxxxxxx> >> --- >> Documentation/ABI/testing/sysfs-bus-iio | 7 +++ >> Documentation/DocBook/iio.tmpl | 2 +- >> drivers/iio/iio_core.h | 3 + >> drivers/iio/industrialio-core.c | 107 ++++++++++++++++++++++++++++++-- >> drivers/iio/industrialio-event.c | 19 +++++- >> drivers/iio/industrialio-trigger.c | 2 +- >> include/linux/iio/iio.h | 10 +-- >> 7 files changed, 134 insertions(+), 16 deletions(-) >> >> diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio >> index 3c66248..4602006 100644 >> --- a/Documentation/ABI/testing/sysfs-bus-iio >> +++ b/Documentation/ABI/testing/sysfs-bus-iio >> @@ -32,6 +32,13 @@ Description: >> Description of the physical chip / device for device X. >> Typically a part number. >> >> +What: /sys/bus/iio/devices/iio:deviceX/clockid >> +KernelVersion: 4.5 >> +Contact: linux-iio@xxxxxxxxxxxxxxx >> +Description: >> + Identifier (clockid_t) of current posix clock used to timestamp >> + buffered samples and events for device X. > As it's been written into a sysfs attribute I'd normally prefer to see a > descriptive string for something like this. What do others think? > clockid_t is clearly fixed abi so this makes reasonable sense. Are there > other sysfs attributes to select the clock already present elsewhere in the > kernel? Very same thoughts here. clockid_t is already ABI so we don't have to be afraid exposing values that might change, but at the same time a string would be more suitable for sysfs. -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
