Commit a02dcde5 authored by Nathan Chancellor's avatar Nathan Chancellor Committed by Dmitry Torokhov
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Input: touchscreen - avoid bitwise vs logical OR warning 



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: default avatarNathan Chancellor <nathan@kernel.org>
Reported-by: default avatarNick Desaulniers <ndesaulniers@google.com>
Reviewed-by: default avatarNick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20211014205757.3474635-1-nathan@kernel.org


Signed-off-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
parent 3378a07d

drivers/input/touchscreen.c

+21 −21
Original line number Diff line number Diff line
@@ -80,12 +80,12 @@ void touchscreen_parse_properties(struct input_dev *input, bool multitouch, 


	data_present = touchscreen_get_prop_u32(dev, "touchscreen-min-x",

						input_abs_get_min(input, axis_x),

						&minimum) |

		       touchscreen_get_prop_u32(dev, "touchscreen-size-x",

						&minimum);

	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-size-x",

						 input_abs_get_max(input,

								   axis_x) + 1,

						&maximum) |

		       touchscreen_get_prop_u32(dev, "touchscreen-fuzz-x",

						 &maximum);

	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-fuzz-x",

						 input_abs_get_fuzz(input, axis_x),

						 &fuzz);

	if (data_present)
@@ -93,12 +93,12 @@ void touchscreen_parse_properties(struct input_dev *input, bool multitouch, 


	data_present = touchscreen_get_prop_u32(dev, "touchscreen-min-y",

						input_abs_get_min(input, axis_y),

						&minimum) |

		       touchscreen_get_prop_u32(dev, "touchscreen-size-y",

						&minimum);

	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-size-y",

						 input_abs_get_max(input,

								   axis_y) + 1,

						&maximum) |

		       touchscreen_get_prop_u32(dev, "touchscreen-fuzz-y",

						 &maximum);

	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-fuzz-y",

						 input_abs_get_fuzz(input, axis_y),

						 &fuzz);

	if (data_present)
@@ -108,8 +108,8 @@ void touchscreen_parse_properties(struct input_dev *input, bool multitouch, 
	data_present = touchscreen_get_prop_u32(dev,

						"touchscreen-max-pressure",

						input_abs_get_max(input, axis),

						&maximum) |

		       touchscreen_get_prop_u32(dev,

						&maximum);

	data_present |= touchscreen_get_prop_u32(dev,

						 "touchscreen-fuzz-pressure",

						 input_abs_get_fuzz(input, axis),

						 &fuzz);