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authorDavid S. Miller <davem@davemloft.net>2015-12-03 21:03:21 -0500
committerDavid S. Miller <davem@davemloft.net>2015-12-03 21:09:12 -0500
commitf188b951f33a0464338f94f928338f84fc0e4392 (patch)
tree17ad63719242b1de0266627a1dc92ba869a3ba4e /drivers/usb/host/xhci.c
parent6b20da4d8f3f6a3be9f67e3207f435cfaa5f7f97 (diff)
parent071f5d105a0ae93aeb02197c4ee3557e8cc57a21 (diff)
downloadop-kernel-dev-f188b951f33a0464338f94f928338f84fc0e4392.zip
op-kernel-dev-f188b951f33a0464338f94f928338f84fc0e4392.tar.gz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts: drivers/net/ethernet/renesas/ravb_main.c kernel/bpf/syscall.c net/ipv4/ipmr.c All three conflicts were cases of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/usb/host/xhci.c')
-rw-r--r--drivers/usb/host/xhci.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 6e7dc6f..dfa44d3 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)
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