Date: Sat, 9 Apr 2016 18:01:56 +0200
From: Pavel Machek <pavel@ucw.cz>
To: Felipe Balbi <balbi@ti.com>
Cc: Baolin Wang <baolin.wang@linaro.org>, Greg KH <gregkh@linuxfoundation.org>,
        sre@kernel.org, dbaryshkov@gmail.com, dwmw2@infradead.org,
        peter.chen@freescale.com, stern@rowland.harvard.edu,
        r.baldyga@samsung.com, sojka@merica.cz,
        yoshihiro.shimoda.uh@renesas.com, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org, sameo@linux.intel.com,
        lee.jones@linaro.org, ckeepax@opensource.wolfsonmicro.com,
        broonie@kernel.org, patches@opensource.wolfsonmicro.com,
        linux-pm@vger.kernel.org, device-mainlining@lists.linuxfoundation.org
Subject: Re: [PATCH v4 1/5] gadget: Introduce the notifier functions
Message-ID: <20160409160156.GF19362@xo-6d-61-c0.localdomain>
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Hi!

> >> Also, because soon enough we will have to support USB Power Delivery
> >> with Type C connector, this is bound to change in the coming months.
> >> 
> >> Frankly, I wanted all of this to be decided in userland with the
> >> kernel just providing notification and basic safety checks (we don't
> >> want to allow a bogus userspace daemon frying anybody's devices).
> >> 
> >> How would you feel about that ?
> >
> > So init=/bin/bash boot no longer provides machine that charges itself?
> >
> > That would be bad. Traditionally, hardware controls battery charging,
> > and if hardware needs some help, we should do it in kernel, to mask
> > the difference from userspace.
> 
> this is a very valid point which I hadn't considered :-)
> 
> Seems like kernel it is, no matter how easy or how difficult it gets.

Basically yes. Note that for some bells & whistles, you can require userland help.

For example it would probably be ok if it charged slower than usual... but I guess
that does not really help in this case.

Best regards,
									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html