On 6/12/2012 10:48 AM, Peter Meerwald wrote:
Hello,
Am I missing documentation somewhere?
Documentation/ABI/testing/sysfs-bus-iio.
+ drivers/staging/iio/documentation/sysfs-* for other bits and bobs. Mostly it
should be fairly obvious how stuff lines up.
well, the last statement should be up to the user of the documentation,
not the creator ;)
True enough.
some comments in iio/types.h iio/iio.h would avoid guesswork...
ah, there were. That comment is out of date. This sort of thing is why
we try to keep minimal commenting in there unless absolutely necessary.
is the What: line in sysfs-bus-iio supposed to be comprehensive?
Yes. All sysfs entries should be documented.
If a specific varient of a general element should be in sysfs-bus-iio
If class specific (e.g. only make sense for light sensors) should be
in sysfs-bus-iio-light etc. If device specific (and these take a fair
bit of persuation to be let in) should be in sysfs-bus-iio-light-tsl2563
etc.
I am worried because concepts are explained redundantly in sysfs-bus-iio
for particular channel types; one such concept is that a raw
value can/shall be modified by userspace by offset and scale
Good to clean those up, but they must be documented in those file. It's
pretty much a kernel rule. Those docs are for writers of userspace code
as well. They shouldn't have to go dig in headers to find this stuff out.
this could be easily (?) done near the iio_chan_info_enum definition in
iio.h
it would be nice to do it there, but the abi docs are the definitive source.
sysfs-bus-iio documents what you might see in the wild but not how to
get there
true.
I suppose we could put a reference to say see the docs files...
I have seen the doc, but I find it hard to deduce the concepts from a
collection of sysfs file names
it is not clear/obvious how to arrive at
/sys/.../iio:deviceX/in_capacitanceY-in_capacitanceZ_raw or
Nice complex case...
/sys/bus/iio/devices/iio:deviceX/out_voltageY&Z_raw
err. that's curious. You can't set that... Goes to show I should review
changes to this file more carefully. I just shouted down adding the
stuff that would provide that precisely because it made no sense.
in iio.h:
* @channel: What number or name do we wish to assign the channel.
what is meant by 'name' here?
Oops. Comment has rotted. Drop the name bit if you fancy doing a patch.
so channel is a numerical identifier that is appended to the channel name
if indexed is 1?
yes.
* @indexed: Specify the channel has a numerical index. If not,
* the value in channel will be suppressed for attribute
* but not for event codes. Typically set it to 0 when
* the index is false.
I am not sure what an 'attribute code' is (sysfs name?)
attribute name (which is just a sysfs name as you call it) Again,
could do with fixing.
I am not sure what 'index is false' means
index == 0; Oops, more good points. Thanks!
Given you are doing an excellent job, feel free to send patches.
regards, p.
--
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
