Re: [PATCH v4 2/5] gpio: Add support for Intel LJCA USB GPIO driver

Arnd Bergmann
2023-03-09T14:51:52Z

On Thu, Mar 9, 2023, at 15:18, Linus Walleij wrote:
> On Thu, Mar 9, 2023 at 2:53 PM Andy Shevchenko
> <andriy.shevchenko@linux.intel.com> wrote:
>
> Yups. And I think the solution looks something like this:
>
> u8 obuf[LJCA_GPIO_BUF_SIZE] __aligned(8);
> u8 ibuf[LJCA_GPIO_BUF_SIZE] __aligned(8);
>
> __aligned(4) if it's 32bit DMA I guess? 8 always works that's
> why we use it all over the IIO subsystem.

I think it must be __aligned(ARCH_DMA_MINALIGN), to account
for architectures with non-coherent DMA.

Arnd