linux-kernel - Re: [PATCH 4.1 099/267] phy: twl4030-usb: remove incorrect pm_runtime_get

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20150812080927.14113400@home.neil.brown.name>
Date:	Wed, 12 Aug 2015 08:09:27 +1000
From:	NeilBrown <neil@...wn.name>
To:	Alexander Holler <holler@...oftware.de>
Cc:	Felipe Balbi <balbi@...com>,
	Kishon Vijay Abraham I <kishon@...com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Subject: Re: [PATCH 4.1 099/267] phy: twl4030-usb: remove incorrect
 pm_runtime_get_sync() in probe function.

On Tue, 11 Aug 2015 23:34:17 +0200 Alexander Holler
<holler@...oftware.de> wrote:

> Am 11.08.2015 um 10:29 schrieb NeilBrown:
> 
> > With the current mainline code (plus my twl4030 charger enhancements,
> > which are not deeply relevant), the refcount does go to zero when
> > nothing is plugged in, and goes to 2 when a regular USB cable is
> > plugged in.
> 
> Also I think it's just a little miswording (or extended typo), I'm not 
> using a regular USB cable, but an OTG cable when using the host mode of 
> the musb on the Beagleboard. Just to avoid confusion. Or do you talk 
> about the client mode when it goes to 2?

With an OTG cable, the usage_count would probably got to '1' because
the charger wouldn't be interested.

However the important point is that the usage_count goes to zero when
no cable is plugged in.

> 
> Besides that, I'm sorry to not be of further help. My deeper knowledge 
> about the musb sources in the kernel and u-boot (and the HW in 
> question), has gone lost and I've currently no real reason to refresh 
> that. ;)

Just reporting the problem is sometimes 90% for the bug fixed.
I'm confident I know what is happening.  What isn't clear is how best
to fix it without breaking something else... I suspect Felipe can help
with that.

Thanks,
NeilBrown
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/