On 05/05/2011 05:06 PM, Alan Stern wrote: > On Thu, 5 May 2011, Jan Andersson wrote: > >>>>> I assumed that the pci_write_config_word()s in uhci_*reset_hc would be >>>>> needed in the case where GRUSBHC was used and there also was another >>>>> UCHI controller connected via PCI in the system. After looking at the >>>>> spec I suppose that it will work, as you say, without the writes to the >>>>> legacy support register. >>>> >>>> Unless somebody decides to run a non-PCI-UHCI-enabled kernel in an x86 >>>> PC. Maybe to be safe it would be best to rule out that combination in >>>> the Kconfig: make USB_UHCI_SUPPORT_NON_PCI_HC depend on (USB_UHCI_HCD >>>> && !X86). Would this be acceptable? >>>> >>> >>> I am fine with that. Too bad that I managed to send V2 before seeing >>> this message :-). I will wait for other comments on V2 before adding >>> this in V3. >>> >> >> Hmmm, after a bit more thought: I someone wants to run a >> non-PCI-UHCI-enabled kernel in an x86 PC we would need one more config >> option. > > I was assuming that no one would ever want to do this; in fact, that no > one would ever want to build a kernel with support for both > non-PCI-UHCI and x86. But maybe that's not a good assumption. I don't know. I guess that if such systems exist they would be found in the embedded space and I don't follow x86 embedded. Well, even if we would prevent non-PCI UCHI for x86 now it is relatively easily for someone to enable it later. > >> USB_UHCI_SUPPORT_NON_PCI_HC is currently needed to include the necessary >> stuff for the non-PCI HC so that one must be set. One additional option >> could be introduced to still include the accesses to the legacy support >> register. Another way to solve this would be to add defined(CONFIG_X86) >> in uhci-pci.c (change to patch 6 in V2): > > A better approach is for uhci-pci always to call the reset functions in > pci-quirks. That's what you were planning to do originally, right? > Yes that was done in the first patch and (to state the obvious) it is done now in V2 unless USB_UHCI_SUPPORT_NON_PCI_HC is set. I'll add the && !x86 to USB_UHCI_SUPPORT_NON_PCI_HC if you think that it is the best option. Best regards, Jan -- 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
