IIO documents that trigger names are unique but does not actually guarantee this. You can easily create a software trigger with a duplicate name if you enable CONFIG_IIO_HRTIMER_TRIGGER: mkdir /sys/kernel/config/iio/triggers/hrtimer/\ `cat /sys/bus/iio/devices/trigger0/name` You can also get in this situation if you connect two identical st_sensors. My attempt to fix this is by adding a new 'current_trigger_id' ABI which is a numeric ID (X from triggerX) rather than a non-unique string. I tested that this works as expected when connecting two LIS3DH to the same system. This is in patches 4,5. In theory the current_trigger ABI could be overloaded to looks for something matching "trigger[0-9]+" but this would be nastier. There would be a need to prevent registering triggers that match that expression in order to prevent stuff like: mkdir /sys/kernel/config/iio/triggers/hrtimer/trigger1 Such an overload wouldn't work on read and make it impossible to unambigiously determine the currently selected trigger. Patch 6 disallows registering duplicate trigger names. This makes drivers which currently do that break at probe time. Patch 7 attempts to ensure that all drivers include indio_dev->id when calling iio_trigger_alloc. This obviously changes trigger names. Either 4,5 or 6,7 fix this issue, but 4,5 causes fewer compat issues. Patches 1,2,3 are just minor features in tools/generic_buffer. They supersede the v2 I posted earlier: https://www.spinics.net/lists/linux-iio/msg24867.html Crestez Dan Leonard (7): iio: generic_buffer: Cleanup when receiving signals iio: generic_buffer: Add --device-num option iio: generic_buffer: Add --trigger-num option iio: Add current_trigger_id alternative iio: generic_buffer: Use current_trigger_id iio: Refuse to register triggers with duplicate names iio: Make trigger names unique Documentation/ABI/testing/sysfs-bus-iio | 9 + Documentation/DocBook/iio.tmpl | 4 +- drivers/iio/adc/max1027.c | 4 +- drivers/iio/common/st_sensors/st_sensors_trigger.c | 2 +- drivers/iio/industrialio-trigger.c | 136 ++++++++--- drivers/iio/light/gp2ap020a00f.c | 4 +- tools/iio/generic_buffer.c | 269 ++++++++++++++------- 7 files changed, 309 insertions(+), 119 deletions(-) -- 2.5.5 -- 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
