Commit Graph

88 Commits

Author SHA1 Message Date
Lars-Peter Clausen
cadc2125e1 iio: fix: Keep a reference to the IIO device for open file descriptors
Make sure that the IIO device is not freed while we still have file descriptors
for it.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-09-21 12:45:07 +01:00
Lars-Peter Clausen
a87c82e454 iio: Stop sampling when the device is removed
Make sure to stop sampling when the device is removed, otherwise it will
continue to sample forever.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-09-21 12:36:30 +01:00
Jonathan Cameron
c006ec8384 iio: add info_mask_[shared_by_dir/shared_by_all]
These two additional info_mask bitmaps should allow all 'standard'
numeric attributes to be handled using the read_raw and write_raw
callbacks.  Whilst this should reduce code, the more important element
is that this makes these values easily accessible to in kernel users
of IIO devices.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
2013-09-15 17:45:49 +01:00
Jonathan Cameron
3704432fb1 iio: refactor info mask and ext_info attribute creation.
Introduce an enum to specify whether the attribute is separate or
shared.

Factor out the bitmap handling for loop into a separate function.

Tidy up error handling and add a NULL assignment to squish a false
positive warning from GCC.

Change ext_info shared type from boolean to enum and update in all
drivers.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
2013-09-15 17:43:20 +01:00
Peter Meerwald
899d90bdf4 iio: Add INT_TIME (integration time) channel info attribute
Integration time is in seconds; it controls the measurement
time and influences the gain of a sensor.

There are two typical ways that scaling is implemented in a device:
1) input amplifier,
2) reference to the ADC is changed.
These both result in the accuracy of the ADC varying (by applying its
sampling over a more relevant range).

Integration time is a way of dealing with noise inherent in the analog
sensor itself.  In the case of a light sensor, a mixture of photon noise
and device specific noise.  Photon noise is dealt with by either improving
the efficiency of the sensor, (more photons actually captured) which is not
easily varied dynamically, or by integrating the measurement over a longer
time period.  Note that this can also be thought of as an averaging of a
number of individual samples and is infact sometimes implemented this way.
Altering integration time implies that the duration of a measurement changes,
a fact the device's user may be interested in.

Hence it makes sense to distinguish between integration time and simple
scale. In some devices both types of control are present and whilst they
will have similar effects on the amplitude of the reading, their effect
on the noise of the measurements will differ considerably.

Used by adjd_s311, tsl4531, tcs3472
The following drivers have similar controls (and could be adapted):
* tsl2563 (integration time is controlled via CALIBSCALE among other things)
* tsl2583 (has integration_time device_attr, but driver doesn't use channels yet)
* tsl2x7x (has integration_time attr)

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Cc: Jon Brenner <jon.brenner@ams.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-09-14 21:16:44 +01:00
Oleksandr Kravchenko
d9a0134e7a iio: core: Avoid double minus in sysfs output
This patch fixes the issue with double minus in output when
reading channels from sysfs for IIO_VAL_INT_PLUS_MICRO and
IIO_VAL_INT_PLUS_NANO cases. Until this patch if val and val2
both are negatives output string contains "--" before
digits. It is result of "-%d..." in sprintf() format.

Signed-off-by: Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-08-03 18:41:19 +01:00
Grygorii Strashko
9dabaf5edd iio: core: implement devm_iio_device_alloc/devm_iio_device_free
Add a resource managed devm_iio_device_alloc()/devm_iio_device_free()
to automatically clean up any allocations made by IIO drivers,
thus leading to simplified IIO drivers code.

In addition, this will allow IIO drivers to use other devm_*() API
(like devm_request_irq) and don't care about the race between
iio_device_free() and the release of resources by Device core
during driver removing.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Tested-by: Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-08-03 18:40:37 +01:00
Jonathan Cameron
b9606e2aa9 iio:core drop info_mask from struct iio_info
This has been replaced by the pair of masks info_mask_separate
and info_mask_shared_by_type.  Other variants may follow.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
2013-03-17 19:49:44 +00:00
Jonathan Cameron
8655cc490e iio: Add broken out info_mask fields for shared_by_type and separate
This simplifies the code, removes an extensive layer of 'helper' macros
and gives us twice as much room to play with in these masks before we
have any need to be clever.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
2013-03-17 19:49:09 +00:00
Guenter Roeck
17d82b47a2 iio: Add OF support
Provide bindings and parse OF data during initialization.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-03-16 10:17:59 +00:00
Lars-Peter Clausen
6807d72113 iio: Factor out fixed point number parsing into its own function
Factor out the code for parsing fixed point numbers into its own function and
make this function globally available. This allows us to reuse the code to parse
fixed point numbers in individual IIO drivers.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-11-20 21:26:39 +00:00
Lars-Peter Clausen
c4f0c69367 iio: Add pressure channel type
This patch adds support for a new IIO channel type for pressure measurements.
This can for example be used for barometric pressure sensors.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-11-20 21:26:38 +00:00
Jonathan Cameron
84b36ce5f7 staging:iio: Add support for multiple buffers
Route all buffer writes through the demux.
Addition or removal of a buffer results in tear down and
setup of all the buffers for a given device.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Tested-by: srinivas pandruvada <srinivas.pandruvada@intel.com>
2012-11-10 10:17:21 +00:00
Lars-Peter Clausen
ef4f92c064 iio: Accept a leading '+' sign when parsing fixed point numbers
If we encounter a leading '+' sign just skip over it.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-11-02 09:43:48 +00:00
Lars-Peter Clausen
02330acda7 iio: Reject trailing garbage when parsing fixed point numbers
When parsing a fixed point number IIO stops parsing the string once it has
reached the last requested decimal place. This means that the remainder of the
string is silently accepted regardless, of whether it is part of a valid number
or not. This patch modifies the code to scan the whole string and only accept
valid numbers. Since fract_mult is 0 after the last decimal place any digit that
may follows won't affect the result.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-11-02 09:43:48 +00:00
Lars-Peter Clausen
8f1b7eb114 iio: Do not accept multiple '.' in fixed point numbers
Currently when parsing a fix-point number we silently skip any additional '.'
found in the string.  E.g. '1.2.3.4' gets parsed as '1.234'. This patch
disallows this and returns an error if more than one '.' is encountered.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-11-02 09:43:47 +00:00
Lars-Peter Clausen
103d9fb907 iio: Add a logarithmic fractional value type
For ADCs or DACs the denominator for fractional types often is a power of two.
In this case we can use a shift operation instead of the rather expensive 64 bit
division. This patch adds a new fractional type which expects the denominator to
be specified as the log2 of the actual denominator. E.g. for ADCs and DACs this
will usually be the number of significant bits.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-10-19 18:46:51 +01:00
Lars-Peter Clausen
7985e7c100 iio: Introduce a new fractional value type
Currently IIO uses a decimal fixed point representations for real type numbers.
This patch introduces a new representation for rational type numbers. The number
will be expressed by specifying a numerator and denominator. For converting a
raw value to a processed value multiply it by the numerator and divide it by the
denominator.

The reasoning for introducing this new type is that for a lot of devices the
scale can be represented easily by a fractional number, but it is not possible
to represent it as fixed point number without rounding.  E.g. for a simple DAC
the scale is often the reference voltage divided by the number of possible
values (Usually 2**n_bits - 1). Each driver currently implements the conversion
of this fraction to a fixed point number on its own.

Also when it comes to the in-kernel interface this allows to directly use the
fractional factors to convert a raw value to a processed value. This should on
one hand require less instructions and on the other hand increase the
precision.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-09-15 10:12:22 +01:00
srinivas pandruvada
7c9ab035ac iio: core: Add hysteresis in channel spec
Added hysteresis to the list of channel info enumeration, shared
/separate bit defines and to postfix channel info strings.

Signed-off-by: srinivas pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-09-06 19:04:45 +01:00
Jonathan Cameron
c8b95952e7 IIO: Update email address for Jonathan Cameron.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-09-03 20:26:46 +01:00
Peter Meerwald
99698b4567 iio: whitespace cleanup and removal of semicolon after functions
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-09-03 20:26:43 +01:00
Peter Meerwald
d25b3808db iio: fix typos
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-09-03 20:26:43 +01:00
Jon Brenner
21cd1fab05 IIO channel type and modifiers for CCT and RGBC data
Add iio channel type and modifiers for Correlated Color Temperature (CCT)
and RGBC (red/green/blue/clear) data.
Add CCT and RGBC descriptions to documentation.

Changes:
Revised/condensed RGBC descriptions.

Merge and trivial fix done by Jonathan Cameron.

Signed-off-by: Jon Brenner <jbrenner@taosinc.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-07-10 18:49:26 +01:00
Jonathan Cameron
cf82cb8128 IIO: Add a modifier for x^2+y^2+z^2
There will probably be a number of such modifiers eventually but
this one is used in the adis16240 accelerometer driver.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-06-30 10:15:28 +01:00
Jonathan Cameron
8f5879b20b IIO: Add a modifier for sqrt(x^2+y^2)
There will probably be a number of such modifiers eventually but
this one is used in the adis16204 accelerometer driver.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-06-30 10:15:22 +01:00
Greg Kroah-Hartman
89a86a2da3 Merge branch 'staging-linus' into staging-next
We need this for the pstore fixes that went into the staging-linus branch, so
that things apply properly for the pstore/android code merge.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13 16:57:09 -07:00
Lars-Peter Clausen
74dcd439bf iio: iio_enum_available_read: Prevent possible buffer overflow
Use scnprint instead of snprintf, because snprintf returns the number of bytes
that would have been written to the buffer if there was enough space, and as a
result writing to buf[len-1] might cause a access beyond the buffers limits.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-07 14:26:29 +09:00
Lars-Peter Clausen
5212cc8a9d iio: Add helper functions for enum style channel attributes
We often have the case were we do have a enum style channel attribute. These
attributes have in common that they are a list of string values which usually
map in a 1-to-1 fashion to integer values.

This patch implements some common helper code for implementing enum style
channel attributes using extended channel attributes. The helper functions take
care of converting between the string and integer values, as well providing a
function for "_available" attributes which list all available enum items.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-05 13:47:29 +09:00
Lars-Peter Clausen
e407fd655b iio: Fix potential use after free
There is no guarantee that the last reference to the iio device has already been
dropped when iio_device_free is called. This means that we can up calling
iio_dev_release after iio_device_free which will lead to a use after free. As
the general rule the struct containing the device should always be freed in the
release callback.

This is what this patch does, it moves freeing the iio device struct as well as
releasing the idr reference to the release callback. To ensure that the device
is not freed before calling iio_device_free the device_unregister call in
iio_device_unregister is broken apart. iio_device_unregister will now only call
device_del to remove the device from the system and iio_device_free will call
put_device to drop the reference we obtained in iio_devce_alloc.

We also have to take care that calling iio_device_free without having called
iio_device_register still works (i.e. this can happen if something failed during
device initialization). For this to work properly two minor changes were
necessary: channel_attr_list needs to be initialized in iio_device_alloc and we
have to check whether the chrdev has been registered before releasing it in
iio_device_release.

This change also brings iio_device_unregister and iio_device_free more in sync
with iio_device_register and iio_device_alloc which call device_add and
device_initialize respectively.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 21:15:31 -07:00
Lars-Peter Clausen
e53f5ac52e iio: Use dev_to_iio_dev()
Replace open-coded instances of getting a iio_dev struct from a device struct
with dev_to_iio_dev().

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-14 13:37:45 -07:00
Michael Hennerich
b65d62122f iio: core: introduce IIO_CHAN_INFO_HARDWAREGAIN
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-14 13:15:39 -07:00
Michael Hennerich
67eedba39e iio: core: introduce dB scle: IIO_VAL_INT_PLUS_MICRO_DB
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-14 13:15:38 -07:00
Axel Lin
abd5a2fb39 IIO: industrialio-core: Checking NULL instead of IS_ERR for debugfs_create_dir()
If defined CONFIG_DEBUG_FS, debugfs_create_dir returns NULL on failure.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-08 16:04:11 -07:00
Axel Lin
5a28c87397 IIO: industrialio-core: Use simple_open
Use simple_open to replace iio_debugfs_open.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-08 16:04:11 -07:00
Michael Hennerich
fc6d11398e iio: core: iio_chan_spec_ext_info: Add private handle
There is currently no user, but we might need it in future.
So better add it now, before we have to convert drivers afterwards.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-29 21:26:17 -04:00
Michael Hennerich
a6b12855b5 iio: core: Introduce IIO_ALTVOLTAGE and appropriate channel info elements
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-29 21:26:17 -04:00
Lars-Peter Clausen
7cbb753701 staging:iio: Streamline API function naming
Currently we use two different naming schemes in the IIO API, iio_verb_object
and iio_object_verb. E.g iio_device_register and iio_allocate_device. This
patches renames instances of the later to the former. The patch also renames allocate to
alloc as this seems to be the preferred form throughout the kernel.

In particular the following renames are performed by the patch:
	iio_put_device -> iio_device_put
	iio_allocate_device -> iio_device_alloc
	iio_free_device -> iio_device_free
	iio_get_trigger -> iio_trigger_get
	iio_put_trigger -> iio_trigger_put
	iio_allocate_trigger -> iio_trigger_alloc
	iio_free_trigger -> iio_trigger_free

The conversion was done with the following coccinelle patch with manual fixes to
comments and documentation.

<smpl>
@@
@@
-iio_put_device
+iio_device_put
@@
@@
-iio_allocate_device
+iio_device_alloc
@@
@@
-iio_free_device
+iio_device_free
@@
@@
-iio_get_trigger
+iio_trigger_get
@@
@@
-iio_put_trigger
+iio_trigger_put
@@
@@
-iio_allocate_trigger
+iio_trigger_alloc
@@
@@
-iio_free_trigger
+iio_trigger_free
</smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-29 21:23:49 -04:00
Jonathan Cameron
a980e04609 IIO: Move the core files to drivers/iio
Take the core support + the kfifo buffer implentation out of
staging.  Whilst we are far from done in improving this subsystem
it is now at a stage where the userspae interfaces (provided by
the core) can be considered stable.

Drivers will follow over a longer time scale.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-25 11:11:38 -07:00