@@ -450,8 +450,9 @@ static int xhci_abort_cmd_ring(struct xhci_hcd *xhci, unsigned long flags)
* In the future we should distinguish between -ENODEV and -ETIMEDOUT
* and try to recover a -ETIMEDOUT with a host controller reset.
*/
- ret = xhci_handshake(&xhci->op_regs->cmd_ring,
- CMD_RING_RUNNING, 0, 5 * 1000 * 1000);
+ ret = xhci_handshake_check_state(xhci, &xhci->op_regs->cmd_ring,
+ CMD_RING_RUNNING, 0, 5 * 1000 * 1000,
+ XHCI_STATE_REMOVING);
if (ret < 0) {
xhci_err(xhci, "Abort failed to stop command ring: %d\n", ret);
xhci_halt(xhci);
@@ -84,6 +84,24 @@ int xhci_handshake(void __iomem *ptr, u32 mask, u32 done, u64 timeout_us)
/*
* Disable interrupts and begin the xHCI halting process.
*/
+int xhci_handshake_check_state(struct xhci_hcd *xhci, void __iomem *ptr,
+ u32 mask, u32 done, int usec, unsigned int exit_state)
+{
+ u32 result;
+ int ret;
+
+ ret = readl_poll_timeout_atomic(ptr, result,
+ (result & mask) == done ||
+ result == U32_MAX ||
+ xhci->xhc_state & exit_state,
+ 1, usec);
+
+ if (result == U32_MAX || xhci->xhc_state & exit_state)
+ return -ENODEV;
+
+ return ret;
+}
+
void xhci_quiesce(struct xhci_hcd *xhci)
{
u32 halted;
@@ -201,7 +219,8 @@ int xhci_reset(struct xhci_hcd *xhci, u64 timeout_us)
if (xhci->quirks & XHCI_INTEL_HOST)
udelay(1000);
- ret = xhci_handshake(&xhci->op_regs->command, CMD_RESET, 0, timeout_us);
+ ret = xhci_handshake_check_state(xhci, &xhci->op_regs->command,
+ CMD_RESET, 0, timeout_us, XHCI_STATE_REMOVING);
if (ret)
return ret;
@@ -2119,6 +2119,8 @@ void xhci_free_container_ctx(struct xhci_hcd *xhci,
/* xHCI host controller glue */
typedef void (*xhci_get_quirks_t)(struct device *, struct xhci_hcd *);
int xhci_handshake(void __iomem *ptr, u32 mask, u32 done, u64 timeout_us);
+int xhci_handshake_check_state(struct xhci_hcd *xhci, void __iomem *ptr,
+ u32 mask, u32 done, int usec, unsigned int exit_state);
void xhci_quiesce(struct xhci_hcd *xhci);
int xhci_halt(struct xhci_hcd *xhci);
int xhci_start(struct xhci_hcd *xhci);
In some situations where xhci removal happens parallel to xhci_handshake, we enoughter a scenario where the xhci_handshake will fails because the status does not change the entire duration of polling. This causes the xhci_handshake to timeout resulting in long wait which might lead to watchdog timeout. The API handles command timeout which may happen upon XHCI stack removal. Check for xhci state and exit the handshake if xhci is removed. Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com> --- v2: Fixed compilation error. drivers/usb/host/xhci-ring.c | 5 +++-- drivers/usb/host/xhci.c | 21 ++++++++++++++++++++- drivers/usb/host/xhci.h | 2 ++ 3 files changed, 25 insertions(+), 3 deletions(-)