On Thu, Oct 14, 2021 at 1:58 PM Nathan Chancellor <nathan@xxxxxxxxxx> wrote: > > 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. > > Link: https://github.com/ClangBuiltLinux/linux/issues/1472 > Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> Thanks for the patch! Reported-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > --- > drivers/input/touchscreen.c | 42 ++++++++++++++++++------------------- > 1 file changed, 21 insertions(+), 21 deletions(-) > > diff --git a/drivers/input/touchscreen.c b/drivers/input/touchscreen.c > index dd18cb917c4d..4620e20d0190 100644 > --- a/drivers/input/touchscreen.c > +++ b/drivers/input/touchscreen.c > @@ -80,27 +80,27 @@ 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", > - input_abs_get_max(input, > - axis_x) + 1, > - &maximum) | > - touchscreen_get_prop_u32(dev, "touchscreen-fuzz-x", > - input_abs_get_fuzz(input, axis_x), > - &fuzz); > + &minimum); > + data_present |= touchscreen_get_prop_u32(dev, "touchscreen-size-x", > + input_abs_get_max(input, > + axis_x) + 1, > + &maximum); > + data_present |= touchscreen_get_prop_u32(dev, "touchscreen-fuzz-x", > + input_abs_get_fuzz(input, axis_x), > + &fuzz); > if (data_present) > touchscreen_set_params(input, axis_x, minimum, maximum - 1, fuzz); > > 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", > - input_abs_get_max(input, > - axis_y) + 1, > - &maximum) | > - touchscreen_get_prop_u32(dev, "touchscreen-fuzz-y", > - input_abs_get_fuzz(input, axis_y), > - &fuzz); > + &minimum); > + data_present |= touchscreen_get_prop_u32(dev, "touchscreen-size-y", > + input_abs_get_max(input, > + axis_y) + 1, > + &maximum); > + data_present |= touchscreen_get_prop_u32(dev, "touchscreen-fuzz-y", > + input_abs_get_fuzz(input, axis_y), > + &fuzz); > if (data_present) > touchscreen_set_params(input, axis_y, minimum, maximum - 1, fuzz); > > @@ -108,11 +108,11 @@ 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, > - "touchscreen-fuzz-pressure", > - input_abs_get_fuzz(input, axis), > - &fuzz); > + &maximum); > + data_present |= touchscreen_get_prop_u32(dev, > + "touchscreen-fuzz-pressure", > + input_abs_get_fuzz(input, axis), > + &fuzz); > if (data_present) > touchscreen_set_params(input, axis, 0, maximum, fuzz); > > > base-commit: a41392e0877a271007e9209e63c34cab7527eb43 > -- > 2.33.1.637.gf443b226ca > > -- Thanks, ~Nick Desaulniers
