Dear Felipe Balbi, > 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 ? Maybe do it like the clock framework does? Just my 5 cents ... > 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 ? Best regards, Marek Vasut -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
