linux-stable.git/drivers/input/touchscreen/of_touchscreen.c, branch linux-4.9.y

Input: touchscreen - avoid bitwise vs logical OR warning

2021-12-22T08:05:15+00:00

commit a02dcde595f7cbd240ccd64de96034ad91cffc40 upstream.

A new warning in clang points out a few places in this driver where a
bitwise OR is being used with boolean types:

drivers/input/touchscreen.c:81:17: warning: use of bitwise '|' with boolean operands [-Wbitwise-instead-of-logical]
        data_present = touchscreen_get_prop_u32(dev, "touchscreen-min-x",
                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This use of a bitwise OR is intentional, as bitwise operations do not
short circuit, which allows all the calls to touchscreen_get_prop_u32()
to happen so that the last parameter is initialized while coalescing the
results of the calls to make a decision after they are all evaluated.

To make this clearer to the compiler, use the '|=' operator to assign
the result of each touchscreen_get_prop_u32() call to data_present,
which keeps the meaning of the code the same but makes it obvious that
every one of these calls is expected to happen.

Signed-off-by: Nathan Chancellor 
Reported-by: Nick Desaulniers 
Reviewed-by: Nick Desaulniers 
Link: https://lore.kernel.org/r/20211014205757.3474635-1-nathan@kernel.org
Signed-off-by: Dmitry Torokhov 
Signed-off-by: Anders Roxell 
Signed-off-by: Greg Kroah-Hartman

Input: of_touchscreen - add support for inverted / swapped axes

2016-07-15T21:50:53+00:00

Extend touchscreen_parse_properties() with support for the
touchscreen-inverted-x/y and touchscreen-swapped-x-y properties and
add touchscreen_set_mt_pos() and touchscreen_report_pos() helper
functions for storing coordinates into a input_mt_pos struct, or
directly reporting them, taking these properties into account.

This commit also modifies the existing callers of
touchscreen_parse_properties() to pass in NULL for the new third
argument, keeping the existing behavior.

Signed-off-by: Hans de Goede 
Signed-off-by: Dmitry Torokhov

Input: of_touchscreen - switch to using device properties

2015-07-12T00:26:45+00:00

Let's switch form OF to device properties so that common parsing code could
work not only on device tree but also on ACPI-based platforms.

Reviewed-by: Roger Quadros 
Signed-off-by: Dmitry Torokhov

Input: of_touchscreen - fix setting max values on X/Y axis

2015-07-12T00:26:37+00:00

The binding specification says that "touchscreen-size-x" and "-y" specify
horizontal and vertical resolution of the touchscreen and therefore maximum
absolute coordinates should be reduced by 1 since we are starting with 0.

Reviewed-by: Roger Quadros 
Signed-off-by: Dmitry Torokhov

Input: of_touchscreen - always issue warning if axis is not set up

2015-07-12T00:26:13+00:00

Do issue warning about axis that is present in device tree but not specified
by the driver even in case of multi-touch axis as callers now tell us if they
expect multi-touch data or not.

Reviewed-by: Roger Quadros 
Signed-off-by: Dmitry Torokhov

Input: improve parsing OF parameters for touchscreens

2015-06-25T21:45:46+00:00

When applying touchscreen parameters specified in device tree let's make
sure we keep whatever setup was done by the driver and not reset the
missing values to zero.

Reported-by: Pavel Machek 
Tested-by: Pavel Machek 
Signed-off-by: Dmitry Torokhov

Input: of_touchscreen - register multitouch axes

2015-03-24T19:00:40+00:00

So far, the DT parsing code was only setting up the regular input axes,
completely ignoring their multitouch counter parts.

Fill them with the same parameters than the regular axes.

Signed-off-by: Maxime Ripard 
Signed-off-by: Dmitry Torokhov

Input: of_touchscreen - rework the DT parsing function

2015-03-24T19:00:39+00:00

The DT parsing function currently duplicates a lot of the code to parse the
touchscreen DT properties. In order to ease further additions to this
parsing routine, rework it slightly to create new helper functions.

Signed-off-by: Maxime Ripard 
Signed-off-by: Dmitry Torokhov

Input: add common DT binding for touchscreens

2014-05-29T07:05:59+00:00

Add common DT binding documentation for touchscreen devices and
implement input_parse_touchscreen_of_params, which parses the common
properties and configures the input device accordingly.

The method currently does not interpret the axis inversion properties,
since there is no matching flag in the generic linux input device.

Reviewed-by: Pavel Machek 
Acked-by: Aaro Koskinen 
Signed-off-by: Sebastian Reichel 
Signed-off-by: Dmitry Torokhov