| Message ID | Pine.LNX.4.44L0.1305021304500.1436-100000@iolanthe.rowland.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thursday 02 May 2013, Alan Stern wrote: > On Thu, 2 May 2013, Arnd Bergmann wrote: > > It relies more on "depends" than "select". I don't know how > important this is in the end. 'select' is sometimes problematic, but the only use that I try to avoid is having one Kconfig symbol that is both user-selectable standalone and selected by something else. > It doesn't add a new USB_UHCI_GRLIB symbol; instead it uses > SPARC_LEON in several places. I tend to think the new symbol > is nicer. > > It doesn't add a new USB_UHCI_PCI symbol. > > It improves the dependency list for USB_UHCI_HCD. > > It removes the help text for USB_UHCI_PLATFORM, thereby making > that symbol not user-configurable. I don't see any reason why > the user should need to worry about this -- the choice should > be a very simple one: build UHCI support or don't build it. If > the user chooses to build it then it should include support for > all the compatible bus glues. (This last decision may need to > be changed if more bus glues get added.) > > What do you think of my patch as compared to yours? I think in the end it comes down to the question where you want to head with your driver. The way I did my version was going towards making it similar to EHCI, with stand-alone bus glue drivers and a core that is just a library module but does not register a device_driver by itself. Given that there are just three bus glues from UHCI, and at most two of them enabled at the same time, I don't see a direct need for UHCI to go down the same route as EHCI. If you want to just leave this driver alone, your patch is simpler and has the same effect in the end. Otherwise I think my patch avoids changing it all again once the driver gets reworked. Things might also get a little messy if we are seeing a lot of other platforms beside VIA VT8500 use UHCI, but I think that is rather unlikely. Arnd
On Thu, 2 May 2013, Arnd Bergmann wrote: > > What do you think of my patch as compared to yours? > > I think in the end it comes down to the question where you want to > head with your driver. The way I did my version was going towards > making it similar to EHCI, with stand-alone bus glue drivers > and a core that is just a library module but does not register > a device_driver by itself. > > Given that there are just three bus glues from UHCI, and at most > two of them enabled at the same time, I don't see a direct need > for UHCI to go down the same route as EHCI. If you want to just > leave this driver alone, your patch is simpler and has the same > effect in the end. Otherwise I think my patch avoids changing it > all again once the driver gets reworked. Okay then, I'll submit my patch to Greg after the merge window closes. > Things might also get a little messy if we are seeing a lot > of other platforms beside VIA VT8500 use UHCI, but I think that > is rather unlikely. Indeed. UHCI is the oldest of the host controller standards; people aren't about to start creating a whole bunch of new implementations of it. Even Intel no longer uses UHCI on their more recent motherboards. Alan Stern
Index: usb-3.9/drivers/usb/host/Kconfig =================================================================== --- usb-3.9.orig/drivers/usb/host/Kconfig +++ usb-3.9/drivers/usb/host/Kconfig @@ -507,7 +507,7 @@ endif # USB_OHCI_HCD config USB_UHCI_HCD tristate "UHCI HCD (most Intel and VIA) support" - depends on PCI || SPARC_LEON || ARCH_VT8500 + depends on PCI || USB_UHCI_SUPPORT_NON_PCI_HC ---help--- The Universal Host Controller Interface is a standard by Intel for accessing the USB hardware in the PC (which is also called the USB @@ -524,26 +524,19 @@ config USB_UHCI_HCD config USB_UHCI_SUPPORT_NON_PCI_HC bool - depends on USB_UHCI_HCD - default y if (SPARC_LEON || ARCH_VT8500) + default y if (SPARC_LEON || USB_UHCI_PLATFORM) config USB_UHCI_PLATFORM - bool "Generic UHCI Platform Driver support" - depends on USB_UHCI_SUPPORT_NON_PCI_HC + bool default y if ARCH_VT8500 - ---help--- - Enable support for generic UHCI platform devices that require no - additional configuration. config USB_UHCI_BIG_ENDIAN_MMIO bool - depends on USB_UHCI_SUPPORT_NON_PCI_HC && SPARC_LEON - default y + default y if SPARC_LEON config USB_UHCI_BIG_ENDIAN_DESC bool - depends on USB_UHCI_SUPPORT_NON_PCI_HC && SPARC_LEON - default y + default y if SPARC_LEON config USB_FHCI_HCD tristate "Freescale QE USB Host Controller support"