On Fri, May 11, 2012 at 06:01:37AM +0000, Chen Peter-B29397 wrote: > > > > > > > Thanks for working on this, but it is just a PHY list, not the PHY > > layer > > > used by PHY driver and controller driver who wants to use PHY. > > > Besides, no USB Spec says there is relationship between OTG and USB PHY. > > > Heikki's (including mine) aim is separate PHY from OTG, and create a > > > generic PHY layer. A generic PHY layer is like below: > > > > > > - There is separate folder at drivers/usb/phy, which includes generic > > PHY > > > files and platform PHY drivers. > > > - Platform PHY driver will add itself to PHY list, and implement kinds > > of > > > PHY utilities, like init, suspend, wakeup, charger detector, etc. > > > - The PHY user (controller driver, no only otg driver) will get the PHY, > > > and use it. > > > > Completely agree with you. But before we have the generic PHY layer, > > we got to have multi-phy support. It's needed for usb3 controller in > > OMAP5 where it needs usb2 phy and usb3 phy. > > > I see. > > Felipe, would you give me some suggestion that my generic PHY work > should be on current tree or you think Kishon's patchset is ok, and I should > be based his work when it is in your usb tree? Kishon's patchset is a starting point. There are still many questions to be answered: how to we associate a PHY with a particular controller ? How to handle situations with multiple PHYs of the same type ? What about PHYs which are used for different buses other than USB ? For example on OMAP5 we have the same RX/TX Serdes used for USB3 and SATA, ideally we would have only one PHY driver instantiated multiple times for USB3 and SATA. Kishon's work is targetted at a kernel-wide PHY layer because of that, but we need to do it incrementally and it's likely to take more than a couple major releases to get it right, so we should try to do small steps to avoid regressions. Even though Kishon's patchset doesn't allow for multiple PHYs of the same type, it's still better than what we have today - only a single global PHY pointer -, right ? -- balbi
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