On Mon, 20 Dec 2021 at 11:59, Greg KH greg@kroah.com wrote:
On Fri, Dec 17, 2021 at 03:41:19PM +0100, Anders Roxell wrote:
From: Nathan Chancellor nathan@kernel.org
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 nathan@kernel.org Reported-by: Nick Desaulniers ndesaulniers@google.com Reviewed-by: Nick Desaulniers ndesaulniers@google.com Link: https://lore.kernel.org/r/20211014205757.3474635-1-nathan@kernel.org Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Anders Roxell anders.roxell@linaro.org
drivers/input/touchscreen/of_touchscreen.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-)
Also needed in 5.10.y and 5.4.y.
Please be more careful next time.
Yes I will, I'm sorry.
Cheers, Anders