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authorElric Fu <elricfu1@gmail.com>2012-06-27 16:30:57 +0800
committerBen Hutchings <ben@decadent.org.uk>2012-10-17 03:48:25 +0100
commitdf045069dcc9242c4de84d2a117af313f7b00853 (patch)
tree056f0b0c0c523b516f090a06c860af7f1303d64a /drivers/usb/host
parentb89d0660eba658f9afa5ddeabc742e07bcaabea7 (diff)
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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: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'drivers/usb/host')
-rw-r--r--drivers/usb/host/xhci-ring.c3
-rw-r--r--drivers/usb/host/xhci.c6
-rw-r--r--drivers/usb/host/xhci.h4
3 files changed, 11 insertions, 2 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index c7c530c..9b17a79 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -309,6 +309,9 @@ 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 */
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 48b048f..d2d3114 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -105,9 +105,10 @@ int xhci_halt(struct xhci_hcd *xhci)
ret = handshake(xhci, &xhci->op_regs->status,
STS_HALT, STS_HALT, XHCI_MAX_HALT_USEC);
- if (!ret)
+ if (!ret) {
xhci->xhc_state |= XHCI_STATE_HALTED;
- else
+ xhci->cmd_ring_state = CMD_RING_STATE_STOPPED;
+ } else
xhci_warn(xhci, "Host not halted after %u microseconds.\n",
XHCI_MAX_HALT_USEC);
return ret;
@@ -573,6 +574,7 @@ static int xhci_run_finished(struct xhci_hcd *xhci)
return -ENODEV;
}
xhci->shared_hcd->state = HC_STATE_RUNNING;
+ xhci->cmd_ring_state = CMD_RING_STATE_RUNNING;
if (xhci->quirks & XHCI_NEC_HOST)
xhci_ring_cmd_db(xhci);
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 44d518a..430163d 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1402,6 +1402,10 @@ struct xhci_hcd {
/* data structures */
struct xhci_device_context_array *dcbaa;
struct xhci_ring *cmd_ring;
+ unsigned int cmd_ring_state;
+#define CMD_RING_STATE_RUNNING (1 << 0)
+#define CMD_RING_STATE_ABORTED (1 << 1)
+#define CMD_RING_STATE_STOPPED (1 << 2)
unsigned int cmd_ring_reserved_trbs;
struct xhci_ring *event_ring;
struct xhci_erst erst;