USB: EHCI, OHCI: handover changes
This patch (as887) changes the way ehci-hcd and ohci-hcd handle a loss
of VBUS power during suspend. In order for the USB-persist facility
to work correctly, it is necessary for low- and full-speed devices
attached to a high-speed port to be handed back to the companion
controller during resume processing.
This entails three changes: adding code to ehci-hcd to perform the
handover, removing code from ohci-hcd to turn off ports during
root-hub reinit, and adding code to ohci-hcd to turn on ports during
PCI controller resume. (Other bus glue resume methods for platforms
supporting high-speed controllers would need a similar change, if any
existed.)
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index f4d301b..3e80de7 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -28,6 +28,87 @@
/*-------------------------------------------------------------------------*/
+#ifdef CONFIG_USB_PERSIST
+
+static int ehci_hub_control(
+ struct usb_hcd *hcd,
+ u16 typeReq,
+ u16 wValue,
+ u16 wIndex,
+ char *buf,
+ u16 wLength
+);
+
+/* After a power loss, ports that were owned by the companion must be
+ * reset so that the companion can still own them.
+ */
+static void ehci_handover_companion_ports(struct ehci_hcd *ehci)
+{
+ u32 __iomem *reg;
+ u32 status;
+ int port;
+ __le32 buf;
+ struct usb_hcd *hcd = ehci_to_hcd(ehci);
+
+ if (!ehci->owned_ports)
+ return;
+
+ /* Give the connections some time to appear */
+ msleep(20);
+
+ port = HCS_N_PORTS(ehci->hcs_params);
+ while (port--) {
+ if (test_bit(port, &ehci->owned_ports)) {
+ reg = &ehci->regs->port_status[port];
+ status = ehci_readl(ehci, reg);
+
+ /* Port already owned by companion? */
+ if (status & PORT_OWNER)
+ clear_bit(port, &ehci->owned_ports);
+ else
+ ehci_hub_control(hcd, SetPortFeature,
+ USB_PORT_FEAT_RESET, port + 1,
+ NULL, 0);
+ }
+ }
+
+ if (!ehci->owned_ports)
+ return;
+ msleep(90); /* Wait for resets to complete */
+
+ port = HCS_N_PORTS(ehci->hcs_params);
+ while (port--) {
+ if (test_bit(port, &ehci->owned_ports)) {
+ ehci_hub_control(hcd, GetPortStatus,
+ 0, port + 1,
+ (char *) &buf, sizeof(buf));
+
+ /* The companion should now own the port,
+ * but if something went wrong the port must not
+ * remain enabled.
+ */
+ reg = &ehci->regs->port_status[port];
+ status = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
+ if (status & PORT_OWNER)
+ ehci_writel(ehci, status | PORT_CSC, reg);
+ else {
+ ehci_dbg(ehci, "failed handover port %d: %x\n",
+ port + 1, status);
+ ehci_writel(ehci, status & ~PORT_PE, reg);
+ }
+ }
+ }
+
+ ehci->owned_ports = 0;
+}
+
+#else /* CONFIG_USB_PERSIST */
+
+static inline void ehci_handover_companion_ports(struct ehci_hcd *ehci)
+{ }
+
+#endif
+
#ifdef CONFIG_PM
static int ehci_bus_suspend (struct usb_hcd *hcd)
@@ -60,14 +141,16 @@
* then manually resume them in the bus_resume() routine.
*/
ehci->bus_suspended = 0;
+ ehci->owned_ports = 0;
while (port--) {
u32 __iomem *reg = &ehci->regs->port_status [port];
u32 t1 = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
u32 t2 = t1;
/* keep track of which ports we suspend */
- if ((t1 & PORT_PE) && !(t1 & PORT_OWNER) &&
- !(t1 & PORT_SUSPEND)) {
+ if (t1 & PORT_OWNER)
+ set_bit(port, &ehci->owned_ports);
+ else if ((t1 & PORT_PE) && !(t1 & PORT_SUSPEND)) {
t2 |= PORT_SUSPEND;
set_bit(port, &ehci->bus_suspended);
}
@@ -108,6 +191,7 @@
{
struct ehci_hcd *ehci = hcd_to_ehci (hcd);
u32 temp;
+ u32 power_okay;
int i;
if (time_before (jiffies, ehci->next_statechange))
@@ -120,8 +204,9 @@
* the last user of the controller, not reset/pm hardware keeping
* state we gave to it.
*/
- temp = ehci_readl(ehci, &ehci->regs->intr_enable);
- ehci_dbg(ehci, "resume root hub%s\n", temp ? "" : " after power loss");
+ power_okay = ehci_readl(ehci, &ehci->regs->intr_enable);
+ ehci_dbg(ehci, "resume root hub%s\n",
+ power_okay ? "" : " after power loss");
/* at least some APM implementations will try to deliver
* IRQs right away, so delay them until we're ready.
@@ -184,6 +269,9 @@
ehci_writel(ehci, INTR_MASK, &ehci->regs->intr_enable);
spin_unlock_irq (&ehci->lock);
+
+ if (!power_okay)
+ ehci_handover_companion_ports(ehci);
return 0;
}
@@ -448,7 +536,8 @@
) {
struct ehci_hcd *ehci = hcd_to_ehci (hcd);
int ports = HCS_N_PORTS (ehci->hcs_params);
- u32 __iomem *status_reg = &ehci->regs->port_status[wIndex - 1];
+ u32 __iomem *status_reg = &ehci->regs->port_status[
+ (wIndex & 0xff) - 1];
u32 temp, status;
unsigned long flags;
int retval = 0;