lkml.org 
[lkml]   [2014]   [Oct]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 3.13 040/163] usb: host: xhci: fix compliance mode workaround
    Date
    3.13.11.9 -stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Felipe Balbi <balbi@ti.com>

    commit 96908589a8b2584b1185f834d365f5cc360e8226 upstream.

    Commit 71c731a (usb: host: xhci: Fix Compliance Mode
    on SN65LVP3502CP Hardware) implemented a workaround
    for a known issue with Texas Instruments' USB 3.0
    redriver IC but it left a condition where any xHCI
    host would be taken out of reset if port was placed
    in compliance mode and there was no device connected
    to the port.

    That condition would trigger a fake connection to a
    non-existent device so that usbcore would trigger a
    warm reset of the port, thus taking the link out of
    reset.

    This has the side-effect of preventing any xHCI host
    connected to a Linux machine from starting and running
    the USB 3.0 Electrical Compliance Suite because the
    port will mysteriously taken out of compliance mode
    and, thus, xHCI won't step through the necessary
    compliance patterns for link validation.

    This patch fixes the issue by just adding a missing
    check for XHCI_COMP_MODE_QUIRK inside
    xhci_hub_report_usb3_link_state() when PORT_CAS isn't
    set.

    This patch should be backported to all kernels containing
    commit 71c731a.

    Fixes: 71c731a (usb: host: xhci: Fix Compliance Mode on SN65LVP3502CP Hardware)
    Cc: Alexis R. Cortes <alexis.cortes@ti.com>
    Signed-off-by: Felipe Balbi <balbi@ti.com>
    Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Signed-off-by: Kamal Mostafa <kamal@canonical.com>
    ---
    drivers/usb/host/xhci-hub.c | 8 +++++---
    1 file changed, 5 insertions(+), 3 deletions(-)

    diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
    index d0997e3..e44be08 100644
    --- a/drivers/usb/host/xhci-hub.c
    +++ b/drivers/usb/host/xhci-hub.c
    @@ -471,7 +471,8 @@ static void xhci_hub_report_usb2_link_state(u32 *status, u32 status_reg)
    }

    /* Updates Link Status for super Speed port */
    -static void xhci_hub_report_usb3_link_state(u32 *status, u32 status_reg)
    +static void xhci_hub_report_usb3_link_state(struct xhci_hcd *xhci,
    + u32 *status, u32 status_reg)
    {
    u32 pls = status_reg & PORT_PLS_MASK;

    @@ -510,7 +511,8 @@ static void xhci_hub_report_usb3_link_state(u32 *status, u32 status_reg)
    * in which sometimes the port enters compliance mode
    * caused by a delay on the host-device negotiation.
    */
    - if (pls == USB_SS_PORT_LS_COMP_MOD)
    + if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) &&
    + (pls == USB_SS_PORT_LS_COMP_MOD))
    pls |= USB_PORT_STAT_CONNECTION;
    }

    @@ -670,7 +672,7 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd,
    }
    /* Update Port Link State */
    if (hcd->speed == HCD_USB3) {
    - xhci_hub_report_usb3_link_state(&status, raw_port_status);
    + xhci_hub_report_usb3_link_state(xhci, &status, raw_port_status);
    /*
    * Verify if all USB3 Ports Have entered U0 already.
    * Delete Compliance Mode Timer if so.
    --
    1.9.1


    \
     
     \ /
      Last update: 2014-10-10 00:21    [W:4.210 / U:0.120 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site