Skip to content

K
Kernel

openeuler / Kernel
1 年多 前同步成功

通知 8
Star 0
Fork 0
K
Kernel
切换分支/标签
  1. 01 10月, 2013 1 次提交
  3. 21 9月, 2013 3 次提交
  5. 04 8月, 2013 2 次提交
  7. 18 3月, 2013 2 次提交
  9. 16 3月, 2013 1 次提交
  11. 21 11月, 2012 2 次提交
  13. 10 11月, 2012 1 次提交
  15. 02 11月, 2012 3 次提交
  17. 20 10月, 2012 1 次提交
  19. 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
  21. 07 9月, 2012 1 次提交
  23. 04 9月, 2012 3 次提交
  25. 11 7月, 2012 1 次提交
  27. 30 6月, 2012 2 次提交
  29. 07 6月, 2012 1 次提交
  31. 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
  33. 15 5月, 2012 3 次提交
  35. 09 5月, 2012 2 次提交
  37. 30 4月, 2012 3 次提交
  39. 26 4月, 2012 2 次提交
  41. 19 4月, 2012 3 次提交