Messages in this thread | | | Date | Wed, 12 Aug 2020 09:54:58 +0800 | From | Kent Gibson <> | Subject | Re: [PATCH v3 02/18] gpio: uapi: define uAPI v2 |
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On Tue, Aug 11, 2020 at 09:11:41PM +0200, Bartosz Golaszewski wrote: > On Sun, Aug 9, 2020 at 3:26 PM Kent Gibson <warthog618@gmail.com> wrote: > > [snip] > > > > +/* > > + * Maximum number of requested lines. > > + * > > + * Must be no greater than 64 as bitmaps are limited to 64-bits, and a > > + * multiple of 2 to ensure 32/64-bit alignment of structs. > > + */ > > +#define GPIO_V2_LINES_MAX 64 > > + > > If we refer to bitmaps for which helpers are defined in > include/linux/bitmap.h then they're not limited to 64-bits. I'd just > say here that we want to fit into 64-bit integers for simplicity. >
Strictly speaking, userspace doesn't know about include/linux/bitmap.h, but I'm happy to remove any ambiguity.
Does this work for you?:
* Must be no greater than 64, as bitmaps are restricted here to 64-bits * for simplicity, and a multiple of 2 to ensure 32/64-bit alignment of * structs.
Cheers, Kent.
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