lkml.org 
[lkml]   [2022]   [Feb]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: regmap: mmio: lack of runtime_pm support for debugfs
After a bit more thinking:

On Fri, Feb 4, 2022 at 11:21 AM Brian Norris <briannorris@chromium.org> wrote:
> Anyway, I'll probably just go with precious_reg() as suggested above.

Unfortunately, precious_reg() wouldn't be quite safe either -- we
could do a single check for pm_runtime_active(), but we have no way of
knowing (guaranteeing) that it will remain active throughout the
remainder of the debugfs operation. For all we know, some other actor
could be *just* finishing with (and PM-suspending) our domain
immediately after the check. And we can't grab a reference, because we
don't have a callback for balancing that back out.

If I really want to solve this, I might have to go with adding a
debugfs-specific runtime_pm flag, and (to avoid too many side effects)
use that with pm_runtime_get_if_active() in regmap-debugfs.c.

Brian

\
 
 \ /
  Last update: 2022-02-04 21:07    [W:0.051 / U:2.332 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site