Re: [PATCH v4 0/7] Implement get_multiple for ACCES and PC/104 drivers

From: Linus Walleij
Date: Mon Mar 26 2018 - 04:31:48 EST


On Thu, Mar 22, 2018 at 1:59 PM, William Breathitt Gray
<vilhelm.gray@xxxxxxxxx> wrote:

> Changes in v4:

I applied the v4 patch set so we get some rotation in linux-next before
the merge window.

If reviewers still find smallish issues they can certainly be fixed in follow-up
patches.

> This patchset implements get_multiple callbacks for the PC104 GPIO
> drivers as well as the PCI-IDIO-16 and PCIe-IDIO-24 GPIO drivers. These
> devices all acquire the multiple input lines with a single read, so
> utilizing the get_multiple callback can provide improvement for those
> users who regularly access multiple input lines.

Did you use the userspace chardev for some interesting experiments
with your set-ups?

I tend to think of your applications as pretty interesting for industry
peers, and a good proof-of-concept for the userspace API.

> While developing this patchset I noticed many of these devices make use
> of Intel 8255 compatible interfaces for their I/O. I may write a generic
> 8255 GPIO driver in the future to reduce some of the redundant code I
> see pop among the drivers for these devices.

Oh!
This guy?
https://en.wikipedia.org/wiki/Intel_8255

Yeah that makes all kind of sense. We are living with the legacy
of the first PCs every day when it comes own to EISA & friends...

Yours,
Linus Walleij