From: Brian Norris <briannorris@chromium.org>
To: Mark Brown <broonie@kernel.org>
Cc: Peng Fan <peng.fan@nxp.com>,
"rafael@kernel.org" <rafael@kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
dl-linux-imx <linux-imx@nxp.com>,
"S.j. Wang" <shengjiu.wang@nxp.com>
Subject: Re: regmap: mmio: lack of runtime_pm support for debugfs
Date: Fri, 4 Feb 2022 12:05:07 -0800 [thread overview]
Message-ID: <CA+ASDXO-61=D0DM+d4dNCbEYV3omroFbbFao3YrUPOYy+7AJUg@mail.gmail.com> (raw)
In-Reply-To: <CA+ASDXP+KeiRKASFakDjJ=cZPD_rGmV4=JgRH26zQi-uZDdiAQ@mail.gmail.com>
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
prev parent reply other threads:[~2022-02-04 20:07 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-23 5:46 [PATCH] regmap: mmio: prepare/unprepare clk only when read/write peng.fan
2020-04-23 10:39 ` Aisheng Dong
2020-04-23 10:40 ` Mark Brown
2020-04-23 10:51 ` Peng Fan
2020-04-23 11:22 ` Mark Brown
2020-04-24 1:27 ` Peng Fan
2020-04-24 10:30 ` Mark Brown
2022-01-24 23:50 ` regmap: mmio: lack of runtime_pm support for debugfs Brian Norris
2022-02-04 19:02 ` Mark Brown
2022-02-04 19:21 ` Brian Norris
2022-02-04 19:41 ` Mark Brown
2022-02-04 19:53 ` Brian Norris
2022-02-05 18:25 ` Mark Brown
2022-02-04 20:05 ` Brian Norris [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CA+ASDXO-61=D0DM+d4dNCbEYV3omroFbbFao3YrUPOYy+7AJUg@mail.gmail.com' \
--to=briannorris@chromium.org \
--cc=broonie@kernel.org \
--cc=linux-imx@nxp.com \
--cc=linux-kernel@vger.kernel.org \
--cc=peng.fan@nxp.com \
--cc=rafael@kernel.org \
--cc=shengjiu.wang@nxp.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).