Re: [PATCH] spi: bcm2835aux: use 64-bit arithmetic instead of 32-bit

[Gustavo A. R. Silva]

Hi Eric,

On 02/08/2018 02:22 AM, Eric Anholt wrote:
> "Gustavo A. R. Silva" <gustavo@xxxxxxxxxxxxxx> writes:
>
> > Add suffix ULL to constant 9 in order to give the compiler complete
> > information about the proper arithmetic to use. Notice that this
> > constant is used in a context that expects an expression of type
> > unsigned long long (64 bits, unsigned).
> >
> > The expression tfr->len * 9 * 1000000 is currently being evaluated
> > using 32-bit arithmetic.
> >
> > Addresses-Coverity-ID: 1339619
> > Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
>
> The effect looks like it would be that we would have chosen polling mode
> instead of waiting for interrupts for some transfers >477 seconds.
> Seems like a good fix for an unlikely bug.
>
> Reviewed-by: Eric Anholt <eric@xxxxxxxxxx>

Thank you for your review.

--
Gustavo