From b92cc66c047ff7cf587b318fe377061a353c120f Mon Sep 17 00:00:00 2001 From: Elric Fu Date: Wed, 27 Jun 2012 16:31:12 +0800 Subject: xHCI: add aborting command ring function Software have to abort command ring and cancel command when a command is failed or hang. Otherwise, the command ring will hang up and can't handle the others. An example of a command that may hang is the Address Device Command, because waiting for a SET_ADDRESS request to be acknowledged by a USB device is outside of the xHC's ability to control. To cancel a command, software will initialize a command descriptor for the cancel command, and add it into a cancel_cmd_list of xhci. Sarah: Fixed missing newline on "Have the command ring been stopped?" debugging statement. This patch should be backported to kernels as old as 3.0, that contain the commit 7ed603ecf8b68ab81f4c83097d3063d43ec73bb8 "xhci: Add an assertion to check for virt_dev=0 bug." That commit papers over a NULL pointer dereference, and this patch fixes the underlying issue that caused the NULL pointer dereference. Signed-off-by: Elric Fu Signed-off-by: Sarah Sharp Tested-by: Miroslav Sabljic Cc: stable@vger.kernel.org --- drivers/usb/host/xhci.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'drivers/usb/host/xhci.h') diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 33f24e9fa766..fdfcebf342e8 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1256,6 +1256,13 @@ struct xhci_td { union xhci_trb *last_trb; }; +/* command descriptor */ +struct xhci_cd { + struct list_head cancel_cmd_list; + struct xhci_command *command; + union xhci_trb *cmd_trb; +}; + struct xhci_dequeue_state { struct xhci_segment *new_deq_seg; union xhci_trb *new_deq_ptr; @@ -1425,6 +1432,7 @@ struct xhci_hcd { #define CMD_RING_STATE_RUNNING (1 << 0) #define CMD_RING_STATE_ABORTED (1 << 1) #define CMD_RING_STATE_STOPPED (1 << 2) + struct list_head cancel_cmd_list; unsigned int cmd_ring_reserved_trbs; struct xhci_ring *event_ring; struct xhci_erst erst; @@ -1702,6 +1710,8 @@ static inline void xhci_unregister_plat(void) /* xHCI host controller glue */ typedef void (*xhci_get_quirks_t)(struct device *, struct xhci_hcd *); +int handshake(struct xhci_hcd *xhci, void __iomem *ptr, + u32 mask, u32 done, int usec); void xhci_quiesce(struct xhci_hcd *xhci); int xhci_halt(struct xhci_hcd *xhci); int xhci_reset(struct xhci_hcd *xhci); @@ -1792,6 +1802,8 @@ void xhci_queue_config_ep_quirk(struct xhci_hcd *xhci, unsigned int slot_id, unsigned int ep_index, struct xhci_dequeue_state *deq_state); void xhci_stop_endpoint_command_watchdog(unsigned long arg); +int xhci_cancel_cmd(struct xhci_hcd *xhci, struct xhci_command *command, + union xhci_trb *cmd_trb); void xhci_ring_ep_doorbell(struct xhci_hcd *xhci, unsigned int slot_id, unsigned int ep_index, unsigned int stream_id); -- cgit v1.2.2