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| author | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2015-12-15 14:51:17 +0100 |
|---|---|---|
| committer | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2015-12-15 14:51:17 +0100 |
| commit | e6d111cd909551cec5902358db1e25dcaa8c86bb (patch) | |
| tree | 99673aec563c76a1a4d7ca2d31b90b47549ae40b /drivers/usb/host/xhci.c | |
| parent | 1dcb97e485420a25461cc44d43f987c8bbf50e7a (diff) | |
| parent | 07cc49f66973f49a391c91bf4b158fa0f2562ca8 (diff) | |
Merge tag 'v4.1.15' into toradex_vf_4.1-nextColibri_VF_LinuxImageV2.5Beta3_20151215
This is the 4.1.15 stable release
Diffstat (limited to 'drivers/usb/host/xhci.c')
| -rw-r--r-- | drivers/usb/host/xhci.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 26f62b2b33f8..1e6d7579709e 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -175,6 +175,16 @@ int xhci_reset(struct xhci_hcd *xhci) command |= CMD_RESET; writel(command, &xhci->op_regs->command); + /* Existing Intel xHCI controllers require a delay of 1 mS, + * after setting the CMD_RESET bit, and before accessing any + * HC registers. This allows the HC to complete the + * reset operation and be ready for HC register access. + * Without this delay, the subsequent HC register access, + * may result in a system hang very rarely. + */ + if (xhci->quirks & XHCI_INTEL_HOST) + udelay(1000); + ret = xhci_handshake(&xhci->op_regs->command, CMD_RESET, 0, 10 * 1000 * 1000); if (ret) |