diff options
Diffstat (limited to 'drivers/usb/host/xhci-ring.c')
| -rw-r--r-- | drivers/usb/host/xhci-ring.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 75c857ec55b..0b0e720521f 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -289,6 +289,114 @@ void xhci_ring_cmd_db(struct xhci_hcd *xhci) xhci_readl(xhci, &xhci->dba->doorbell[0]); } +static int xhci_abort_cmd_ring(struct xhci_hcd *xhci) +{ + u64 temp_64; + int ret; + + xhci_dbg(xhci, "Abort command ring\n"); + + if (!(xhci->cmd_ring_state & CMD_RING_STATE_RUNNING)) { + xhci_dbg(xhci, "The command ring isn't running, " + "Have the command ring been stopped?\n"); + return 0; + } + + temp_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring); + if (!(temp_64 & CMD_RING_RUNNING)) { + xhci_dbg(xhci, "Command ring had been stopped\n"); + return 0; + } + xhci->cmd_ring_state = CMD_RING_STATE_ABORTED; + xhci_write_64(xhci, temp_64 | CMD_RING_ABORT, + &xhci->op_regs->cmd_ring); + + /* Section 4.6.1.2 of xHCI 1.0 spec says software should + * time the completion od all xHCI commands, including + * the Command Abort operation. If software doesn't see + * CRR negated in a timely manner (e.g. longer than 5 + * seconds), then it should assume that the there are + * larger problems with the xHC and assert HCRST. + */ + ret = handshake(xhci, &xhci->op_regs->cmd_ring, + CMD_RING_RUNNING, 0, 5 * 1000 * 1000); + if (ret < 0) { + xhci_err(xhci, "Stopped the command ring failed, " + "maybe the host is dead\n"); + xhci->xhc_state |= XHCI_STATE_DYING; + xhci_quiesce(xhci); + xhci_halt(xhci); + return -ESHUTDOWN; + } + + return 0; +} + +static int xhci_queue_cd(struct xhci_hcd *xhci, + struct xhci_command *command, + union xhci_trb *cmd_trb) +{ + struct xhci_cd *cd; + cd = kzalloc(sizeof(struct xhci_cd), GFP_ATOMIC); + if (!cd) + return -ENOMEM; + INIT_LIST_HEAD(&cd->cancel_cmd_list); + + cd->command = command; + cd->cmd_trb = cmd_trb; + list_add_tail(&cd->cancel_cmd_list, &xhci->cancel_cmd_list); + + return 0; +} + +/* + * Cancel the command which has issue. + * + * Some commands may hang due to waiting for acknowledgement from + * usb device. It is outside of the xHC's ability to control and + * will cause the command ring is blocked. When it occurs software + * should intervene to recover the command ring. + * See Section 4.6.1.1 and 4.6.1.2 + */ +int xhci_cancel_cmd(struct xhci_hcd *xhci, struct xhci_command *command, + union xhci_trb *cmd_trb) +{ + int retval = 0; + unsigned long flags; + + spin_lock_irqsave(&xhci->lock, flags); + + if (xhci->xhc_state & XHCI_STATE_DYING) { + xhci_warn(xhci, "Abort the command ring," + " but the xHCI is dead.\n"); + retval = -ESHUTDOWN; + goto fail; + } + + /* queue the cmd desriptor to cancel_cmd_list */ + retval = xhci_queue_cd(xhci, command, cmd_trb); + if (retval) { + xhci_warn(xhci, "Queuing command descriptor failed.\n"); + goto fail; + } + + /* abort command ring */ + retval = xhci_abort_cmd_ring(xhci); + if (retval) { + xhci_err(xhci, "Abort command ring failed\n"); + if (unlikely(retval == -ESHUTDOWN)) { + spin_unlock_irqrestore(&xhci->lock, flags); + usb_hc_died(xhci_to_hcd(xhci)->primary_hcd); + xhci_dbg(xhci, "xHCI host controller is dead.\n"); + return retval; + } + } + +fail: + spin_unlock_irqrestore(&xhci->lock, flags); + return retval; +} + void xhci_ring_ep_doorbell(struct xhci_hcd *xhci, unsigned int slot_id, unsigned int ep_index, |