lkml.org 
[lkml]   [2016]   [Jan]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 4/5] HSI: nokia-modem: drop support for disabled pm
Hi,

On Sun, Jan 31, 2016 at 12:24:34PM +0100, Pali Rohár wrote:
> On Sunday 31 January 2016 02:19:46 Sebastian Reichel wrote:
> > Disabled power management means, that the driver can only be
> > used together with further out-of-tree kernel patches. There
> > is no reason to support this in the mainline kernel and not
> > having support for it means, that userspace can automatically
> > detect if we are running kernel based power management.
>
> I'm against this change. It will break support for (patched) Maemo and
> proprietary Nokia sscd modem daemon.

Do you have some links for this? So far my assumption was, that sscd
requires /sys/devices/platform/gpio-switch, so you either need to
patch sscd somehow, or patch the kernel to provide gpio-switch, or
provide some kind of userspace wrapper.

> Also you can export GPIOs manually via sysfs and touch that state. Which
> means that you can do power management with mainline kernel even if you
> set nokia-modem.pm=0.

Yeah... You export GPIOs manually. Did you actually try this? You
will end up with exactly the same result as nokia-modem.pm=1, just
with a few less symlinks. Also you have to make sure, that you
actually exported the right gpios, since the global gpio number is
dependent on the gpio-controller registration order.

> So please drop this patch.

Please provide facts, that Maemo can use pm=0 without additional
kernel patches and does not work with pm=1.

-- Sebastian
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2016-01-31 17:41    [W:0.825 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site