lkml.org 
[lkml]   [2016]   [May]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [RFC 0/7] Deal with iio trigger names
From
Date
On 23/05/16 19:39, Crestez Dan Leonard wrote:
> 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:
Please don't do this in future. When reviewing lots of series, one tends
to relying on sorting by name to make sure you find the latest version of
a series. Do this and people don't know there is a new version embedded in
a different series (in this case I picked up V2 when you had found an issue
in it).

Jonathan
>
> 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(-)
>

\
 
 \ /
  Last update: 2016-05-29 22:01    [W:0.108 / U:0.244 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site