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 <jan@gaisler.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c
index 5176c53..cd482fc 100644
--- a/drivers/usb/host/uhci-hcd.c
+++ b/drivers/usb/host/uhci-hcd.c
@@ -167,6 +167,79 @@
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.
*/