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path: root/drivers/usb/host/ohci-hub.c
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Diffstat (limited to 'drivers/usb/host/ohci-hub.c')
-rw-r--r--drivers/usb/host/ohci-hub.c87
1 files changed, 52 insertions, 35 deletions
diff --git a/drivers/usb/host/ohci-hub.c b/drivers/usb/host/ohci-hub.c
index 7ea9a7b31155..32bbce9718f0 100644
--- a/drivers/usb/host/ohci-hub.c
+++ b/drivers/usb/host/ohci-hub.c
@@ -359,21 +359,24 @@ static void ohci_finish_controller_resume(struct usb_hcd *hcd)
/* Carry out polling-, autostop-, and autoresume-related state changes */
static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
- int any_connected)
+ int any_connected, int rhsc_status)
{
int poll_rh = 1;
- int rhsc;
+ int rhsc_enable;
- rhsc = ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC;
- switch (ohci->hc_control & OHCI_CTRL_HCFS) {
+ /* Some broken controllers never turn off RHCS in the interrupt
+ * status register. For their sake we won't re-enable RHSC
+ * interrupts if the interrupt bit is already active.
+ */
+ rhsc_enable = ohci_readl(ohci, &ohci->regs->intrenable) &
+ OHCI_INTR_RHSC;
+ switch (ohci->hc_control & OHCI_CTRL_HCFS) {
case OHCI_USB_OPER:
- /* If no status changes are pending, enable status-change
- * interrupts.
- */
- if (!rhsc && !changed) {
- rhsc = OHCI_INTR_RHSC;
- ohci_writel(ohci, rhsc, &ohci->regs->intrenable);
+ /* If no status changes are pending, enable RHSC interrupts. */
+ if (!rhsc_enable && !rhsc_status && !changed) {
+ rhsc_enable = OHCI_INTR_RHSC;
+ ohci_writel(ohci, rhsc_enable, &ohci->regs->intrenable);
}
/* Keep on polling until we know a device is connected
@@ -383,7 +386,7 @@ static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
if (any_connected ||
!device_may_wakeup(&ohci_to_hcd(ohci)
->self.root_hub->dev)) {
- if (rhsc)
+ if (rhsc_enable)
poll_rh = 0;
} else {
ohci->autostop = 1;
@@ -396,34 +399,45 @@ static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
ohci->autostop = 0;
ohci->next_statechange = jiffies +
STATECHANGE_DELAY;
- } else if (rhsc && time_after_eq(jiffies,
+ } else if (time_after_eq(jiffies,
ohci->next_statechange)
&& !ohci->ed_rm_list
&& !(ohci->hc_control &
OHCI_SCHED_ENABLES)) {
ohci_rh_suspend(ohci, 1);
- poll_rh = 0;
+ if (rhsc_enable)
+ poll_rh = 0;
}
}
break;
- /* if there is a port change, autostart or ask to be resumed */
case OHCI_USB_SUSPEND:
case OHCI_USB_RESUME:
+ /* if there is a port change, autostart or ask to be resumed */
if (changed) {
if (ohci->autostop)
ohci_rh_resume(ohci);
else
usb_hcd_resume_root_hub(ohci_to_hcd(ohci));
- } else {
- if (!rhsc && (ohci->autostop ||
- ohci_to_hcd(ohci)->self.root_hub->
- do_remote_wakeup))
- ohci_writel(ohci, OHCI_INTR_RHSC,
- &ohci->regs->intrenable);
- /* everything is idle, no need for polling */
+ /* If remote wakeup is disabled, stop polling */
+ } else if (!ohci->autostop &&
+ !ohci_to_hcd(ohci)->self.root_hub->
+ do_remote_wakeup) {
poll_rh = 0;
+
+ } else {
+ /* If no status changes are pending,
+ * enable RHSC interrupts
+ */
+ if (!rhsc_enable && !rhsc_status) {
+ rhsc_enable = OHCI_INTR_RHSC;
+ ohci_writel(ohci, rhsc_enable,
+ &ohci->regs->intrenable);
+ }
+ /* Keep polling until RHSC is enabled */
+ if (rhsc_enable)
+ poll_rh = 0;
}
break;
}
@@ -441,18 +455,22 @@ static inline int ohci_rh_resume(struct ohci_hcd *ohci)
* autostop isn't used when CONFIG_PM is turned off.
*/
static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
- int any_connected)
+ int any_connected, int rhsc_status)
{
/* If RHSC is enabled, don't poll */
if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
return 0;
- /* If no status changes are pending, enable status-change interrupts */
- if (!changed) {
- ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
- return 0;
- }
- return 1;
+ /* If status changes are pending, continue polling.
+ * Conversely, if no status changes are pending but the RHSC
+ * status bit was set, then RHSC may be broken so continue polling.
+ */
+ if (changed || rhsc_status)
+ return 1;
+
+ /* It's safe to re-enable RHSC interrupts */
+ ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
+ return 0;
}
#endif /* CONFIG_PM */
@@ -467,6 +485,7 @@ ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
struct ohci_hcd *ohci = hcd_to_ohci (hcd);
int i, changed = 0, length = 1;
int any_connected = 0;
+ int rhsc_status;
unsigned long flags;
spin_lock_irqsave (&ohci->lock, flags);
@@ -492,12 +511,10 @@ ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
length++;
}
- /* Some broken controllers never turn off RHCS in the interrupt
- * status register. For their sake we won't re-enable RHSC
- * interrupts if the flag is already set.
- */
- if (ohci_readl(ohci, &ohci->regs->intrstatus) & OHCI_INTR_RHSC)
- changed = 1;
+ /* Clear the RHSC status flag before reading the port statuses */
+ ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrstatus);
+ rhsc_status = ohci_readl(ohci, &ohci->regs->intrstatus) &
+ OHCI_INTR_RHSC;
/* look at each port */
for (i = 0; i < ohci->num_ports; i++) {
@@ -517,7 +534,7 @@ ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
}
hcd->poll_rh = ohci_root_hub_state_changes(ohci, changed,
- any_connected);
+ any_connected, rhsc_status);
done:
spin_unlock_irqrestore (&ohci->lock, flags);