[OpenWrt-Devel] [PATCH] [kernel] cp201x: Add GPIO ioctl commands (from Silicon Labs)

Karl Palsson karlp at tweak.net.au
Fri Aug 7 21:14:17 EDT 2015


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

"Ted Hess" <thess at kitschensync.net> wrote:
> After a bit more research - This is what I know:
> 
> The upstream cp210x driver is not completely up-to-date with the driver
> silabs maintains on
> their site. In their own words: "... unfortunately GPIO is not something
> that has been
> committed to the Linux kernel yet for community maintenance. We leave
> the drivers on our
> website, even though they are a bit behind the curve of the maintained
> kernels, to
> demonstrate how to do this quickly using an ioctl() call."
> 
> I also noted that the patch I submitted is not up-to-date with their
> latest devices which are
> supported in their driver - whoops.
> 
> I could try to submit this upstream even if it was snatched from their
> driver. Is this OK?

There 's two people working on this on the linux-usb mailing list "right
now"  (I'm on apalling internet right now, so I can't find links for you
to the archives)  The ioctl approach has been totally vetoed, any ioctl
for gpios on this chips will never merge upstream, the silabs driver is
for people who don't care about those sorts of things.  gpios for ftdi
is also landing, and it's finally being accepted that all of these
things are actually, you know, important, so it's finally getting there,
but the ioctl approach is out.  I wouldn't personally be a fan of
openwrt putting in ioctls even for "just for now" as it's something you
can maintain in your own tree if you really need this sort of
functionality.

> 
> There is a small relay controller package (crelay) that I am going to
> submit to the packages
> repo it this patch gets accepted. It uses the cp210x ioctl interface.

What's happening is it's getting the whole gpiolib interface.  so this
app will only ever work with people using the vendor driver.... _if_ you
need to do it in the kernel.  You can always use libusb to make the same
control requests if you like, and if you're only poking a relay, I'd
imagine it's more than sufficient.  (of course depending on what you
want to be doing at the same time and all that)

Cheers,
Karl P

> 
> -----Original Message----- 
> From: Felix Fietkau
> Sent: Monday, August 03, 2015 2:33 PM
> To: Ted Hess ; OpenWrt developers
> Subject: Re: [OpenWrt-Devel] [PATCH] [kernel] cp201x: Add GPIO ioctl
> commands (from Silicon Labs)
> 
> On 2015-08-03 20:17, Ted Hess wrote:
> > It would probably make sense to do it that way however, there are apps which already use the ioctl interface on this device and 
> > this
> > code came directly from the the manufacturer's linux driver.
> >
> > I'm not sure how to add general GPIO support for a specific USB device? Things to research...
> Did the manufacturer submit this upstream already, or is somebody else
> (maybe you) going to do so?
> 
> - Felix 
> _______________________________________________
> openwrt-devel mailing list
> openwrt-devel at lists.openwrt.org
> https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-devel

- -- 
Sent using Mailpile, Free Software from www.mailpile.is

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (GNU/Linux)
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=2eLL
-----END PGP SIGNATURE-----
-------------- next part --------------
_______________________________________________
openwrt-devel mailing list
openwrt-devel at lists.openwrt.org
https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-devel


More information about the openwrt-devel mailing list