Hi, On Thu, Jun 20, 2013 at 08:53:05AM +0800, Chao Xie wrote: > >> @@ -2674,6 +2693,9 @@ void usb_remove_hcd(struct usb_hcd *hcd) > >> free_irq(hcd->irq, hcd); > >> } > >> > >> + if (hcd->phy) > >> + usb_phy_shutdown(hcd->phy); > >> + > >> usb_put_dev(hcd->self.root_hub); > >> usb_deregister_bus(&hcd->self); > >> hcd_buffer_destroy(hcd); > >> > > > > I still think that we shouldn't do this because it adds more confusion and is not > > still a generic enough solution. > > > > 1) It is better for the piece of code that does usb_phy_get() to do usb_phy_init/shutdown, > > else there will be lot of confusion. (Felipe pointed this out earlier). > > > > 2) There is no standard way of getting phy for different controllers. It is mostly platform > > dependent and it is best to leave this to the controller drivers. (Pointed out by Alan). > > > > 3) Controllers can have multiple PHYs. e.g. ehci-omap has one PHY per port and it supports > > 3 ports. This is also platform specific and difficult to handle generically. > > > > 4) Controllers can have specific timing requirements as to when the PHY is initialized relative > > to the controller being initialized. I've pointed OMAP specific stuff in the earlier patch. > > > > Considering all these points, I think we should leave things as they are. It isn't that hard > > for controllers to manage phy_init() and phy_shutdown(), and there is not much code space saved > > when compared to the complexity it creates if we move them to HCD layer. > > > In fact, the PHY setting and handling is related to platform or SOC, > and for different SOC they can > have same EHCI HCD but they PHY handling can be different. > Omap'a case is the example, and i think some other vendors may have > silimar cases. > From above point, It is better to leave the PHY initialization and > shutdown to be done by each echi-xxx driver. > > So Alan and Felipe > What are your ideas about it? If we have so many exceptions, then sure. But eventually, the common case should be added generically with a flag so that non-generic cases (like OMAP) can request to handle the PHY by themselves. Alan ? -- balbi
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