ehci: Check individual port status registers on resume
If a device plug/unplug is detected on an ATI SB700 USB controller in D3,
it appears to set the port status register but not the controller status
register. As a result we'll fail to detect the plug event. Check the port
status register on resume as well in order to catch this case.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: stable <stable@kernel.org> [after .39-rc1 is out]
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 c0b37fe..ae0140d 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -106,6 +106,27 @@
ehci->owned_ports = 0;
}
+static int ehci_port_change(struct ehci_hcd *ehci)
+{
+ int i = HCS_N_PORTS(ehci->hcs_params);
+
+ /* First check if the controller indicates a change event */
+
+ if (ehci_readl(ehci, &ehci->regs->status) & STS_PCD)
+ return 1;
+
+ /*
+ * Not all controllers appear to update this while going from D3 to D0,
+ * so check the individual port status registers as well
+ */
+
+ while (i--)
+ if (ehci_readl(ehci, &ehci->regs->port_status[i]) & PORT_CSC)
+ return 1;
+
+ return 0;
+}
+
static void ehci_adjust_port_wakeup_flags(struct ehci_hcd *ehci,
bool suspending, bool do_wakeup)
{
@@ -173,7 +194,7 @@
}
/* Does the root hub have a port wakeup pending? */
- if (!suspending && (ehci_readl(ehci, &ehci->regs->status) & STS_PCD))
+ if (!suspending && ehci_port_change(ehci))
usb_hcd_resume_root_hub(ehci_to_hcd(ehci));
spin_unlock_irqrestore(&ehci->lock, flags);