From d3219d1c4c9ab7cd959f8f294420faf5f936cf55 Mon Sep 17 00:00:00 2001 From: Jan Andersson Date: Fri, 6 May 2011 12:00:17 +0200 Subject: USB: UHCI: Support non-PCI host controllers This patch is part of a series that extend the UHCI HCD to support non-PCI host controllers. This patch also extends the uhci_{read,write}* functions to allow accesses to registers not mapped into PCI I/O space. This extension also includes the addition of a void __iomem pointer to the uhci structure. A new Kconfig option is added to signal that the system has a non-PCI HC. If this Kconfig option is set, uhci-hcd.c will include generic reset functions for systems that do not make use of keyboard and mouse legacy support. PCI controllers will still always use the reset functions from pci-quirks This patch is followed by a patch that adds bus glue for the first non-PCI UHCI HC. Signed-off-by: Jan Andersson Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/uhci-hcd.c | 73 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) (limited to 'drivers/usb/host/uhci-hcd.c') diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c index 5176c537b95a..cd482fcc05da 100644 --- a/drivers/usb/host/uhci-hcd.c +++ b/drivers/usb/host/uhci-hcd.c @@ -167,6 +167,79 @@ static void check_and_reset_hc(struct uhci_hcd *uhci) finish_reset(uhci); } +#if defined(CONFIG_USB_UHCI_SUPPORT_NON_PCI_HC) +/* + * The two functions below are generic reset functions that are used on systems + * that do not have keyboard and mouse legacy support. We assume that we are + * running on such a system if CONFIG_USB_UHCI_SUPPORT_NON_PCI_HC is defined. + */ + +/* + * Make sure the controller is completely inactive, unable to + * generate interrupts or do DMA. + */ +static void uhci_generic_reset_hc(struct uhci_hcd *uhci) +{ + /* Reset the HC - this will force us to get a + * new notification of any already connected + * ports due to the virtual disconnect that it + * implies. + */ + uhci_writew(uhci, USBCMD_HCRESET, USBCMD); + mb(); + udelay(5); + if (uhci_readw(uhci, USBCMD) & USBCMD_HCRESET) + dev_warn(uhci_dev(uhci), "HCRESET not completed yet!\n"); + + /* Just to be safe, disable interrupt requests and + * make sure the controller is stopped. + */ + uhci_writew(uhci, 0, USBINTR); + uhci_writew(uhci, 0, USBCMD); +} + +/* + * Initialize a controller that was newly discovered or has just been + * resumed. In either case we can't be sure of its previous state. + * + * Returns: 1 if the controller was reset, 0 otherwise. + */ +static int uhci_generic_check_and_reset_hc(struct uhci_hcd *uhci) +{ + unsigned int cmd, intr; + + /* + * When restarting a suspended controller, we expect all the + * settings to be the same as we left them: + * + * Controller is stopped and configured with EGSM set; + * No interrupts enabled except possibly Resume Detect. + * + * If any of these conditions are violated we do a complete reset. + */ + + cmd = uhci_readw(uhci, USBCMD); + if ((cmd & USBCMD_RS) || !(cmd & USBCMD_CF) || !(cmd & USBCMD_EGSM)) { + dev_dbg(uhci_dev(uhci), "%s: cmd = 0x%04x\n", + __func__, cmd); + goto reset_needed; + } + + intr = uhci_readw(uhci, USBINTR); + if (intr & (~USBINTR_RESUME)) { + dev_dbg(uhci_dev(uhci), "%s: intr = 0x%04x\n", + __func__, intr); + goto reset_needed; + } + return 0; + +reset_needed: + dev_dbg(uhci_dev(uhci), "Performing full reset\n"); + uhci_generic_reset_hc(uhci); + return 1; +} +#endif /* CONFIG_USB_UHCI_SUPPORT_NON_PCI_HC */ + /* * Store the basic register settings needed by the controller. */ -- cgit v1.2.3