Re: [RESEND PATCH v4 3/8] gpio: 104-dio-48e: Utilize for_each_set_clump macro

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Oct 15, 2018 at 01:59:33PM +0200, Rasmus Villemoes wrote:
> On 2018-10-14 06:19, William Breathitt Gray wrote:
> 
> > a bit value of 0 in the
> > bits array does not necessarily mean the input was not requested, but
> > may instead mean that the value at the input is 0;
> 
> sure enough, but...
> 
> > therefore, the caller
> > must keep track of the requested inputs rather than try to deduce them
> > from the values in the bits array.
> 
> ...I don't agree that this logically follows. A caller might reasonably
> expect not to find any bits set in positions other than those in mask. A
> simple example would be caller that just tried to ask "are any of
> _these_ inputs set"; it would be reasonable to implement that using
> bitmap_empty() on the returned bitset, without first having to mask by
> the mask he passed in.
> 
> Rasmus

I see your point. It would be good to keep the behavior consistent with
what would be expected by the user -- and adding an additional AND
operation at the end to mask away the unrequested bits should not really
affect the performance to a discernible degree -- so I'll submit a
patchset implementing the mask for these drivers some time this weekend.

William Breathitt Gray



[Index of Archives]     [Linux SPI]     [Linux Kernel]     [Linux ARM (vger)]     [Linux ARM MSM]     [Linux Omap]     [Linux Arm]     [Linux Tegra]     [Fedora ARM]     [Linux for Samsung SOC]     [eCos]     [Linux Fastboot]     [Gcc Help]     [Git]     [DCCP]     [IETF Announce]     [Security]     [Linux MIPS]     [Yosemite Campsites]

  Powered by Linux