For the USB3.0 controller, USB 2.0 reset not driven while
port is in Resume state. So, do not program the USB 2.0 reset
(PORTSC[PR]=1) while in Resume state.

Signed-off-by: Rajat Srivastava <rajat.srivast...@nxp.com>
Signed-off-by: Sriram Dash <sriram.d...@nxp.com>
Signed-off-by: Rajesh Bhagat <rajesh.bha...@nxp.com>
---
 drivers/usb/host/xhci-hub.c | 28 +++++++++++++++++++++++++++-
 drivers/usb/host/xhci.h     |  1 +
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 730b9fd..3def0dd 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -878,7 +878,7 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 
wValue,
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
        int max_ports;
        unsigned long flags;
-       u32 temp, status;
+       u32 temp, status, tmp_status = 0;
        int retval = 0;
        __le32 __iomem **port_array;
        int slot_id;
@@ -1098,6 +1098,32 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, 
u16 wValue,
                        spin_lock_irqsave(&xhci->lock, flags);
                        break;
                case USB_PORT_FEAT_RESET:
+                       /*
+                        * Erratum : A010129
+                        * Synopsys STAR 9000962562.
+                        * USB 2.0 Reset Not Driven While Port in Resume
+                        * While in USB 2.0 resume state (the PORTSC.PLS
+                        * register bit is set to 4'd15), if the xHCI driver
+                        * programs the PORTSC.PR register bit to 1, the
+                        * controller does not drive a USB 2.0 reset
+                        * and it does not generate a PORTSC.PRC=1 interrupt.
+                        * So, The xHCI driver should not program a USB
+                        * 2.0 reset (PORTSC.PR=1) while in resume
+                        * (PORTSC.PLS=4'd15).
+                        */
+                       if (xhci->quirks & XHCI_PORT_RST_ON_RESUME) {
+                               tmp_status = readl(port_array[wIndex]);
+                               spin_unlock_irqrestore(&xhci->lock, flags);
+                               if (!DEV_SUPERSPEED(tmp_status)
+                                       && (tmp_status & PORT_PLS_MASK)
+                                       == XDEV_RESUME) {
+                                       xhci_err(xhci, "skip port reset\n");
+                                       spin_lock_irqsave(&xhci->lock, flags);
+                                       break;
+                               }
+                               spin_lock_irqsave(&xhci->lock, flags);
+                       }
+
                        temp = (temp | PORT_RESET);
                        writel(temp, port_array[wIndex]);
 
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index b2c1dc5..c07e267 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1653,6 +1653,7 @@ struct xhci_hcd {
 #define XHCI_MTK_HOST          (1 << 21)
 #define XHCI_SSIC_PORT_UNUSED  (1 << 22)
 #define XHCI_NO_64BIT_SUPPORT  (1 << 23)
+#define XHCI_PORT_RST_ON_RESUME        (1 << 24)
        unsigned int            num_active_eps;
        unsigned int            limit_active_eps;
        /* There are two roothubs to keep track of bus suspend info for */
-- 
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to