1 files changed, 122 insertions, 1 deletions

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index c59d5b5b6c7d..6ece0ed288d4 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -26,6 +26,7 @@
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/slab.h>
+#include <linux/dmi.h>
 
 #include "xhci.h"
 
@@ -398,6 +399,95 @@ static void xhci_msix_sync_irqs(struct xhci_hcd *xhci)
 
 #endif
 
+static void compliance_mode_recovery(unsigned long arg)
+{
+        struct xhci_hcd *xhci;
+        struct usb_hcd *hcd;
+        u32 temp;
+        int i;
+
+        xhci = (struct xhci_hcd *)arg;
+
+        for (i = 0; i < xhci->num_usb3_ports; i++) {
+                temp = xhci_readl(xhci, xhci->usb3_ports[i]);
+                if ((temp & PORT_PLS_MASK) == USB_SS_PORT_LS_COMP_MOD) {
+                        /*
+                         * Compliance Mode Detected. Letting USB Core
+                         * handle the Warm Reset
+                         */
+                        xhci_dbg(xhci, "Compliance Mode Detected->Port %d!\n",
+                                        i + 1);
+                        xhci_dbg(xhci, "Attempting Recovery routine!\n");
+                        hcd = xhci->shared_hcd;
+
+                        if (hcd->state == HC_STATE_SUSPENDED)
+                                usb_hcd_resume_root_hub(hcd);
+
+                        usb_hcd_poll_rh_status(hcd);
+                }
+        }
+
+        if (xhci->port_status_u0 != ((1 << xhci->num_usb3_ports)-1))
+                mod_timer(&xhci->comp_mode_recovery_timer,
+                        jiffies + msecs_to_jiffies(COMP_MODE_RCVRY_MSECS));
+}
+
+/*
+ * Quirk to work around issue generated by the SN65LVPE502CP USB3.0 re-driver
+ * that causes ports behind that hardware to enter compliance mode sometimes.
+ * The quirk creates a timer that polls every 2 seconds the link state of
+ * each host controller's port and recovers it by issuing a Warm reset
+ * if Compliance mode is detected, otherwise the port will become "dead" (no
+ * device connections or disconnections will be detected anymore). Becasue no
+ * status event is generated when entering compliance mode (per xhci spec),
+ * this quirk is needed on systems that have the failing hardware installed.
+ */
+static void compliance_mode_recovery_timer_init(struct xhci_hcd *xhci)
+{
+        xhci->port_status_u0 = 0;
+        init_timer(&xhci->comp_mode_recovery_timer);
+
+        xhci->comp_mode_recovery_timer.data = (unsigned long) xhci;
+        xhci->comp_mode_recovery_timer.function = compliance_mode_recovery;
+        xhci->comp_mode_recovery_timer.expires = jiffies +
+                        msecs_to_jiffies(COMP_MODE_RCVRY_MSECS);
+
+        set_timer_slack(&xhci->comp_mode_recovery_timer,
+                        msecs_to_jiffies(COMP_MODE_RCVRY_MSECS));
+        add_timer(&xhci->comp_mode_recovery_timer);
+        xhci_dbg(xhci, "Compliance Mode Recovery Timer Initialized.\n");
+}
+
+/*
+ * This function identifies the systems that have installed the SN65LVPE502CP
+ * USB3.0 re-driver and that need the Compliance Mode Quirk.
+ * Systems:
+ * Vendor: Hewlett-Packard -> System Models: Z420, Z620 and Z820
+ */
+static bool compliance_mode_recovery_timer_quirk_check(void)
+{
+        const char *dmi_product_name, *dmi_sys_vendor;
+
+        dmi_product_name = dmi_get_system_info(DMI_PRODUCT_NAME);
+        dmi_sys_vendor = dmi_get_system_info(DMI_SYS_VENDOR);
+
+        if (!(strstr(dmi_sys_vendor, "Hewlett-Packard")))
+                return false;
+
+        if (strstr(dmi_product_name, "Z420") ||
+                        strstr(dmi_product_name, "Z620") ||
+                        strstr(dmi_product_name, "Z820"))
+                return true;
+
+        return false;
+}
+
+static int xhci_all_ports_seen_u0(struct xhci_hcd *xhci)
+{
+        return (xhci->port_status_u0 == ((1 << xhci->num_usb3_ports)-1));
+}
+
+
 /*
  * Initialize memory for HCD and xHC (one-time init).
  *
@@ -421,6 +511,12 @@ int xhci_init(struct usb_hcd *hcd)
         retval = xhci_mem_init(xhci, GFP_KERNEL);
         xhci_dbg(xhci, "Finished xhci_init\n");
 
+        /* Initializing Compliance Mode Recovery Data If Needed */
+        if (compliance_mode_recovery_timer_quirk_check()) {
+                xhci->quirks |= XHCI_COMP_MODE_QUIRK;
+                compliance_mode_recovery_timer_init(xhci);
+        }
+
         return retval;
 }
 
@@ -629,6 +725,11 @@ void xhci_stop(struct usb_hcd *hcd)
         del_timer_sync(&xhci->event_ring_timer);
 #endif
 
+        /* Deleting Compliance Mode Recovery Timer */
+        if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) &&
+                        (!(xhci_all_ports_seen_u0(xhci))))
+                del_timer_sync(&xhci->comp_mode_recovery_timer);
+
         if (xhci->quirks & XHCI_AMD_PLL_FIX)
                 usb_amd_dev_put();
 
@@ -659,7 +760,7 @@ void xhci_shutdown(struct usb_hcd *hcd)
 {
         struct xhci_hcd *xhci = hcd_to_xhci(hcd);
 
-        if (xhci->quirks && XHCI_SPURIOUS_REBOOT)
+        if (xhci->quirks & XHCI_SPURIOUS_REBOOT)
                 usb_disable_xhci_ports(to_pci_dev(hcd->self.controller));
 
         spin_lock_irq(&xhci->lock);
@@ -806,6 +907,16 @@ int xhci_suspend(struct xhci_hcd *xhci)
         }
         spin_unlock_irq(&xhci->lock);
 
+        /*
+         * Deleting Compliance Mode Recovery Timer because the xHCI Host
+         * is about to be suspended.
+         */
+        if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) &&
+                        (!(xhci_all_ports_seen_u0(xhci)))) {
+                del_timer_sync(&xhci->comp_mode_recovery_timer);
+                xhci_dbg(xhci, "Compliance Mode Recovery Timer Deleted!\n");
+        }
+
         /* step 5: remove core well power */
         /* synchronize irq when using MSI-X */
         xhci_msix_sync_irqs(xhci);
@@ -938,6 +1049,16 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
                 usb_hcd_resume_root_hub(hcd);
                 usb_hcd_resume_root_hub(xhci->shared_hcd);
         }
+
+        /*
+         * If system is subject to the Quirk, Compliance Mode Timer needs to
+         * be re-initialized Always after a system resume. Ports are subject
+         * to suffer the Compliance Mode issue again. It doesn't matter if
+         * ports have entered previously to U0 before system's suspension.
+         */
+        if (xhci->quirks & XHCI_COMP_MODE_QUIRK)
+                compliance_mode_recovery_timer_init(xhci);
+
         return retval;
 }
 #endif  /* CONFIG_PM */