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[RFC,V1,0/2] gpio: set active-state of GPIO lines using device tree

Message ID 1557122501-5183-1-git-send-email-harish_kandiga@mentor.com
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Series gpio: set active-state of GPIO lines using device tree | expand

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Harish Jenny K N May 6, 2019, 6:01 a.m. UTC 
The purpose of this patchset is to add the information of active state
of gpio pin as property into device tree configuration using a
"active-state" property u8 array.

This is useful for user space applications to identify
active state of pins.

We have explored the gpio-hog option which is available to set the
 active states. But with gpio-hog used, the gpio-pin will be held
by kernel or the module using the hog property and the user space
application will not be able to access pin with IOCTL interface
like GPIO_GET_LINEHANDLE_IOCTL, GPIOHANDLE_GET_LINE_VALUES_IOCTL and
 GPIOHANDLE_SET_LINE_VALUES_IOCTL.

Any inputs are welcome.

Please let us know if this has already been discussed/considered or
if this can be solved by an alternate approach

Thanks,
Harish.

Harish Jenny K N (2):
  gpio: make it possible to set active-state on GPIO lines
  dt-bindings: gpio: document the new active-state property

 Documentation/devicetree/bindings/gpio/gpio.txt |  4 +++
 drivers/gpio/gpiolib-devprop.c            | 38 +++++++++++++++++++++++++
 drivers/gpio/gpiolib-of.c                 |  3 ++
 drivers/gpio/gpiolib.h                    |  3 ++
 4 files changed, 48 insertions(+)

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2.7.4