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  1. 21 11月, 2012 1 次提交
  3. 10 11月, 2012 1 次提交
  5. 02 11月, 2012 3 次提交
  7. 20 10月, 2012 1 次提交
  9. 15 9月, 2012 1 次提交
    • L
      iio: Introduce a new fractional value type · 7985e7c1
      由 Lars-Peter Clausen 提交于 
      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: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>
      7985e7c1
  11. 07 9月, 2012 1 次提交
  13. 04 9月, 2012 3 次提交
  15. 11 7月, 2012 1 次提交
  17. 30 6月, 2012 2 次提交
  19. 07 6月, 2012 1 次提交
  21. 05 6月, 2012 2 次提交
    • L
      iio: Add helper functions for enum style channel attributes · 5212cc8a
      由 Lars-Peter Clausen 提交于 
      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: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5212cc8a
    • L
      iio: Fix potential use after free · e407fd65
      由 Lars-Peter Clausen 提交于 
      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: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      e407fd65
  23. 15 5月, 2012 3 次提交
  25. 09 5月, 2012 2 次提交
  27. 30 4月, 2012 3 次提交
  29. 26 4月, 2012 2 次提交
  31. 19 4月, 2012 3 次提交
  33. 14 4月, 2012 1 次提交
  35. 08 3月, 2012 1 次提交
  37. 03 3月, 2012 3 次提交
  39. 25 2月, 2012 2 次提交
    • L
      staging:iio: Add extended IIO channel info · 5f420b42
      由 Lars-Peter Clausen 提交于 
      Sometimes devices have per channel properties which either do not map nicely to
the current channel info scheme (e.g. string properties) or are very device
specific, so it does not make sense to add generic support for them.

Currently drivers define these attributes by hand for each channel. Depending on
the number of channels this can amount to quite a few lines of boilerplate code.
Especially if a driver supports multiple variations of a chip with different
numbers of channels. In this case it becomes necessary to have a individual
attribute list per chip variation and also a individual iio_info struct.

This patch introduces a new scheme for handling such per channel attributes
called extended channel info attributes. A extended channel info attribute
consist of a name, a flag whether it is shared and read and write callbacks.
The read and write callbacks are similar to the {read,write}_raw callbacks and
take a IIO device and a channel as their first parameters, but instead of
pre-parsed integer values they directly get passed the raw string value, which
has been written to the sysfs file.

It is possible to assign a list of extended channel info attributes to a
channel. For each extended channel info attribute the IIO core will create a new
sysfs attribute conforming to the IIO channel naming spec for the channels type,
similar as for normal info attributes. Read and write access to this sysfs
attribute will be redirected to the extended channel info attributes read and
write callbacks.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5f420b42
    • J
      staging:iio:core set the iio_dev.info pointer to null on unregister under lock. · ac917a81
      由 Jonathan Cameron 提交于 
      This prevents use of provider callbacks after it has been unregistered.
Note that all code using this that can be called from a consumer *must*
check the pointer before using and hold the info_exist_lock throughout
the usage of the callbacks in info.
Signed-off-by: NJonathan Cameron <jic23@kernel.org>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      ac917a81
  41. 10 2月, 2012 2 次提交
  43. 23 12月, 2011 1 次提交
    • L
      staging:iio: Drop {mark,unmark}_in_use callbacks · 79335140
      由 Lars-Peter Clausen 提交于 
      These callbacks are currently used by the individual buffer implementations to
ensure that the request_update callback is not issued while the buffer is in use.
But the core already provides sufficient measures to prevent this from happening
in the first place. So it is safe to remove them.

There is one functional change due to this patch. Since the buffer is no longer
marked as in use when the chrdev is opened, it is now possible to enable the
buffer while it is opened. This did not work before, because mark_param_change
did fail if the buffer was marked as in use.
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      79335140