Re: [GIT PULL] USB/PHY driver changes for 4.15-rc1

From: Guenter Roeck
Date: Tue Nov 14 2017 - 11:10:27 EST


On Tue, Nov 14, 2017 at 05:02:53PM +0200, Heikki Krogerus wrote:
> Hi Guenter,
>
> On Tue, Nov 14, 2017 at 06:48:21AM -0800, Guenter Roeck wrote:
> > On 11/14/2017 05:17 AM, Greg KH wrote:
> > > On Mon, Nov 13, 2017 at 09:29:36PM -0800, Linus Torvalds wrote:
> > > > On Mon, Nov 13, 2017 at 8:19 AM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > > > >
> > > > > Other major thing is the typec code that moved out of staging and into
> > > > > the "real" part of the drivers/usb/ tree, which was nice to see happen.
> > > >
> > > > Hmm. So now it asks me about Type-C Port Controller Manager. Fair
> > > > enough. I say "N", because I have none. But then it still asks me
> > > > about that TI TPS6598x driver...
> > > >
> > > > So I do see the _technical_ logic in there - the "TYPEC" config option
> > > > is a hidden internal option, and it's selected by the things that need
> > > > it.
> > > >
> > > > But from a user perspective, this configuration model is really strange.
> > > >
> > > > Why is TYPEC_TCPM something you ask the user, but not "do you want
> > > > Type-C support"? And if you single out the PCM side to ask about, why
> > > > don't you single out the power delivery side?
> > > >
> > > > Wouldn't it make more sense to at least ask whether I want Type-C
> > > > power delivery chips before it then starts asking about individual PD
> > > > drivers, the same way you asked about the port controller before you
> > > > started asking ab out individual port controller drivers?
> > > >
> > > > Or is it just me who finds this a bit odd?
> > >
> > > Yes, it is odd, but then again, so is typec :(
> > >
> > > I think this is an artifact of the code living in two different
> > > directories for a while (drivers/staging/ and drivers/usb) and now
> > > coming together.
> > >
> > > Guenter, can you make up a patch to fix up the Kconfig entries in
> > > drivers/usb/typec/Kconfig to make a bit more sense now that things are
> > > all living in the same place in the tree?
> > >
> >
> > I'll give it a try. Wonder if we should make TYPEC_TCPM implicit (selected)
> > instead of having a dependency on it. After all, its use depends on the
> > selected chip. Any thoughts ?
>
> Sorry, I had not noticed Greg's answer.
>
> My proposal was kinda the opposite. To make the TYPEC user selectable:
> https://lkml.org/lkml/2017/11/14/281
>
> But making TYPEC_TCPM implicit works for me too. It just means the
> user is asked about every Type-C and Power Delivery driver always.
>
I had planned to introduce a configurable TYPEC_PD for "Type-C Power
Delivery support". Just not sure if UCSI would fit into that. But we
can also make TYPEC configurable; I am not religious about that.
Lets go with your patch, since you sent it out already and spent a
lot of time writing up a description.

Guenter