[PATCH 3.14 41/73] usb: xhci: rework root port wake bits if controller isnt allowed to wakeup

Greg Kroah-Hartman
2014-12-05T23:20:22Z

From: Lu Baolu <baolu.lu@linux.intel.com>

commit a1377e5397ab321e21b793ec8cd2b6f12bd3c718 upstream.

When system is being suspended, if host device is not allowed to do wakeup,
xhci_suspend() needs to clear all root port wake on bits. Otherwise, some
platforms may generate spurious wakeup, even if PCI PME# is disabled.

The initial commit ff8cbf250b44 ("xhci: clear root port wake on bits"),
which also got into stable, turned out to not work correctly and had to
be reverted, and is now rewritten.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
[Mathias Nyman: reword commit message]
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/host/xhci-pci.c | 2 +-
drivers/usb/host/xhci-plat.c | 10 +++++++++-
drivers/usb/host/xhci.c | 42 +++++++++++++++++++++++++++++++++++++++++-
drivers/usb/host/xhci.h | 2 +-
4 files changed, 52 insertions(+), 4 deletions(-)

--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -281,7 +281,7 @@ static int xhci_pci_suspend(struct usb_h
if (xhci_compliance_mode_recovery_timer_quirk_check())
pdev->no_d3cold = true;

- return xhci_suspend(xhci);
+ return xhci_suspend(xhci, do_wakeup);
}

static int xhci_pci_resume(struct usb_hcd *hcd, bool hibernated)
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -205,7 +205,15 @@ static int xhci_plat_suspend(struct devi
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct xhci_hcd *xhci = hcd_to_xhci(hcd);

- return xhci_suspend(xhci);
+ /*
+ * xhci_suspend() needs `do_wakeup` to know whether host is allowed
+ * to do wakeup during suspend. Since xhci_plat_suspend is currently
+ * only designed for system suspend, device_may_wakeup() is enough
+ * to dertermine whether host is allowed to do wakeup. Need to
+ * reconsider this when xhci_plat_suspend enlarges its scope, e.g.,
+ * also applies to runtime suspend.
+ */
+ return xhci_suspend(xhci, device_may_wakeup(dev));
}

static int xhci_plat_resume(struct device *dev)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -35,6 +35,8 @@
#define DRIVER_AUTHOR "Sarah Sharp"
#define DRIVER_DESC "'eXtensible' Host Controller (xHC) Driver"

+#define PORT_WAKE_BITS (PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E)
+
/* Some 0.95 hardware can't handle the chain bit on a Link TRB being cleared */
static int link_quirk;
module_param(link_quirk, int, S_IRUGO | S_IWUSR);
@@ -842,13 +844,47 @@ static void xhci_clear_command_ring(stru
xhci_set_cmd_ring_deq(xhci);
}

+static void xhci_disable_port_wake_on_bits(struct xhci_hcd *xhci)
+{
+ int port_index;
+ __le32 __iomem **port_array;
+ unsigned long flags;
+ u32 t1, t2;
+
+ spin_lock_irqsave(&xhci->lock, flags);
+
+ /* disble usb3 ports Wake bits*/
+ port_index = xhci->num_usb3_ports;
+ port_array = xhci->usb3_ports;
+ while (port_index--) {
+ t1 = readl(port_array[port_index]);
+ t1 = xhci_port_state_to_neutral(t1);
+ t2 = t1 & ~PORT_WAKE_BITS;
+ if (t1 != t2)
+ writel(t2, port_array[port_index]);
+ }
+
+ /* disble usb2 ports Wake bits*/
+ port_index = xhci->num_usb2_ports;
+ port_array = xhci->usb2_ports;
+ while (port_index--) {
+ t1 = readl(port_array[port_index]);
+ t1 = xhci_port_state_to_neutral(t1);
+ t2 = t1 & ~PORT_WAKE_BITS;
+ if (t1 != t2)
+ writel(t2, port_array[port_index]);
+ }
+
+ spin_unlock_irqrestore(&xhci->lock, flags);
+}
+
/*
* Stop HC (not bus-specific)
*
* This is called when the machine transition into S3/S4 mode.
*
*/
-int xhci_suspend(struct xhci_hcd *xhci)
+int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
{
int rc = 0;
unsigned int delay = XHCI_MAX_HALT_USEC;
@@ -859,6 +895,10 @@ int xhci_suspend(struct xhci_hcd *xhci)
xhci->shared_hcd->state != HC_STATE_SUSPENDED)
return -EINVAL;

+ /* Clear root port wake on bits if wakeup not allowed. */
+ if (!do_wakeup)
+ xhci_disable_port_wake_on_bits(xhci);
+
/* Don't poll the roothubs on bus suspend. */
xhci_dbg(xhci, "%s: stopping port polling.\n", __func__);
clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1760,7 +1760,7 @@ void xhci_shutdown(struct usb_hcd *hcd);
int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks);

#ifdef CONFIG_PM
-int xhci_suspend(struct xhci_hcd *xhci);
+int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup);
int xhci_resume(struct xhci_hcd *xhci, bool hibernated);
#else
#define xhci_suspend NULL