From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
To: Jan Kotas <jank@cadence.com>
Cc: "alsa-devel@alsa-project.org" <alsa-devel@alsa-project.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"vkoul@kernel.org" <vkoul@kernel.org>,
Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
"sanyog.r.kale@intel.com" <sanyog.r.kale@intel.com>
Subject: Re: [alsa-devel] [PATCH] soundwire: fix pm_runtime_get_sync return code checks
Date: Mon, 8 Apr 2019 12:43:47 -0500 [thread overview]
Message-ID: <ace7e7f7-c3bf-f38c-0e70-da826175e3c5@linux.intel.com> (raw)
In-Reply-To: <92538D7E-C628-40AC-AFE9-52C97B3BC42D@global.cadence.com>
On 4/8/19 2:12 AM, Jan Kotas wrote:
>
>
>> On 5 Apr 2019, at 17:04, Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> wrote:
>>
>> On 4/5/19 2:26 AM, Jan Kotas wrote:
>>>
>>>
>>> ret = pm_runtime_get_sync(slave->bus->dev);
>>> - if (ret < 0)
>>> + if (ret < 0 && ret != -EACCES)
>>>
>> There was a patch submitted on 3/28 by Srinivas Kandagatla who suggested an alternate solution for exactly the same code.
>>
>> + if (pm_runtime_enabled(slave->bus->dev)) {
>> + ret = pm_runtime_get_sync(slave->bus->dev);
>> + if (ret < 0)
>> + return ret;
>>
>> I am far from an expert on pm_runtime but Srinivas' solution looks more elegant to me.
>
> Hello Pierre,
>
> Please take a look at this patch, that was my inspiration:
> https://lists.linuxfoundation.org/pipermail/linux-pm/2011-June/031930.html
The two patches seems to be identical:
static inline bool pm_runtime_enabled(struct device *dev)
{
return !dev->power.disable_depth;
}
static int rpm_resume()
[...]
else if (dev->power.disable_depth > 0)
retval = -EACCES;
However I am still not clear on why this might fail.
I can only think of one possible explanation: there is no explicit
pm_runtime_enable() in the soundwire code, so maybe the expectation is
that the pm_runtime status is inherited from the parent (in the intel
case the PCI driver), and that's missing in non-intel configurations?
> I also took a look, and it seems the value returned by
> pm_runtime_get_syncis simply ignored in a lot of places,
> so checking its value may be excessive.
But not checking seems careless at best...
next prev parent reply other threads:[~2019-04-08 18:23 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-05 7:26 [PATCH] soundwire: fix pm_runtime_get_sync return code checks Jan Kotas
[not found] ` <367316fa-9d92-2dfc-32c4-3e0e8c76ef43@linux.intel.com>
2019-04-08 7:12 ` Jan Kotas
2019-04-08 17:43 ` Pierre-Louis Bossart [this message]
2019-04-14 10:26 ` [alsa-devel] " Vinod Koul
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=ace7e7f7-c3bf-f38c-0e70-da826175e3c5@linux.intel.com \
--to=pierre-louis.bossart@linux.intel.com \
--cc=alsa-devel@alsa-project.org \
--cc=jank@cadence.com \
--cc=linux-kernel@vger.kernel.org \
--cc=sanyog.r.kale@intel.com \
--cc=srinivas.kandagatla@linaro.org \
--cc=vkoul@kernel.org \
/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).