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| author | Elric Fu <elricfu1@gmail.com> | 2012-06-27 16:30:57 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-28 10:02:13 -0700 |
| commit | c76e4de05c23fea3d6ad6df63876a9397dd7c85a (patch) | |
| tree | ad79eb26202dc0539091c49bc6566c4816d6ed0b /drivers/usb/host/xhci-ring.c | |
| parent | 63d9249d5fa183605153928e9f19881fb86e9e81 (diff) | |
| download | kernel_samsung_smdk4412-c76e4de05c23fea3d6ad6df63876a9397dd7c85a.zip kernel_samsung_smdk4412-c76e4de05c23fea3d6ad6df63876a9397dd7c85a.tar.gz kernel_samsung_smdk4412-c76e4de05c23fea3d6ad6df63876a9397dd7c85a.tar.bz2 | |
xHCI: add cmd_ring_state
commit c181bc5b5d5c79b71203cd10cef97f802fb6f9c1 upstream.
Adding cmd_ring_state for command ring. It helps to verify
the current command ring state for controlling the command
ring operations.
This patch should be backported to kernels as old as 3.0. The commit
7ed603ecf8b68ab81f4c83097d3063d43ec73bb8 "xhci: Add an assertion to
check for virt_dev=0 bug." papers over the NULL pointer dereference that
I now believe is related to a timed out Set Address command. This (and
the four patches that follow it) contain the real fix that also allows
VIA USB 3.0 hubs to consistently re-enumerate during the plug/unplug
stress tests.
Signed-off-by: Elric Fu <elricfu1@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Miroslav Sabljic <miroslav.sabljic@avl.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host/xhci-ring.c')
| -rw-r--r-- | drivers/usb/host/xhci-ring.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 152daca..4027779 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -311,6 +311,9 @@ static int room_on_ring(struct xhci_hcd *xhci, struct xhci_ring *ring, /* Ring the host controller doorbell after placing a command on the ring */ void xhci_ring_cmd_db(struct xhci_hcd *xhci) { + if (!(xhci->cmd_ring_state & CMD_RING_STATE_RUNNING)) + return; + xhci_dbg(xhci, "// Ding dong!\n"); xhci_writel(xhci, DB_VALUE_HOST, &xhci->dba->doorbell[0]); /* Flush PCI posted writes */ |