Messages in this thread | | | From | Arnd Bergmann <> | Subject | Re: [PATCH] staging/comedi/dt282x: avoid integer overflow warning | Date | Tue, 15 Mar 2016 22:50:16 +0100 |
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On Tuesday 15 March 2016 21:35:40 Hartley Sweeten wrote: > On Monday, March 14, 2016 3:48 PM, Arnd Bergmann wrote: > > gcc-6 warns about passing negative signed integer into swab16() > > in the dt282x driver: > > <snip> > > > The warning makes sense, though the code is correct as far as I > > can tell. > > > > This disambiguates the operation by making the constant expressions > > we pass here explicitly 'unsigned', which helps to avoid the warning. > > > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > > --- > > drivers/staging/comedi/drivers/dt282x.c | 62 ++++++++++++++++----------------- > > 1 file changed, 31 insertions(+), 31 deletions(-) > > > > diff --git a/drivers/staging/comedi/drivers/dt282x.c b/drivers/staging/comedi/drivers/dt282x.c > > index 40bf00984fa5..d4d45c759c62 100644 > > --- a/drivers/staging/comedi/drivers/dt282x.c > > +++ b/drivers/staging/comedi/drivers/dt282x.c > > @@ -69,48 +69,48 @@ > > * Register map > > */ > > #define DT2821_ADCSR_REG 0x00 > > -#define DT2821_ADCSR_ADERR (1 << 15) > > -#define DT2821_ADCSR_ADCLK (1 << 9) > > -#define DT2821_ADCSR_MUXBUSY (1 << 8) > > -#define DT2821_ADCSR_ADDONE (1 << 7) > > -#define DT2821_ADCSR_IADDONE (1 << 6) > > +#define DT2821_ADCSR_ADERR (1u << 15) > > Changing all of these to use the BIT() macro should also avoid the warning.
Yes, but it won't work for the ones that have more than one bit:
#define DT2821_SUPCSR_DS_AD_TRIG (3 << 10)
I considered using BIT() but decided against it for consistency.
Arnd
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