Messages in this thread | | | Date | Wed, 25 Mar 2015 16:28:29 +0100 | Subject | Re: [PATCH] gpio: pcf857x: restore the initial line state of all pcf lines | From | Linus Walleij <> |
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On Wed, Mar 18, 2015 at 2:21 PM, Kishon Vijay Abraham I <kishon@ti.com> wrote: >[Me] >> Specify exactly what stuff may happen after the reboot notifier. > > okay, it's assumed the device may be used (active) till the shutdown handler > of that particular device is called. > > In this particular case we are restoring the initial line state of all pcf > lines even though we don't know if the devices connected to it are still > being active, which might cause a contention as explained by NM [1]
OK I understand this, just that I want to know if it is a practical problem, i.e. do you run into it? Does the system lock up?
> If the reboot notifier gets invoked after the shutdown handler then we could > be sure that restoring the initial line state of the pcf lines wouldn't > affect the devices connected to it.
OK so does it?
ftrace is your friend.
Yours, Linus Walleij
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