patches.renesas/0191-usb-xhci-use-list_is_singular-for-cmd_list.patch

From 103b843025dddaf40557b50aa0c4163311765e39 Mon Sep 17 00:00:00 2001
From: Lu Baolu <baolu.lu@linux.intel.com>
Date: Mon, 23 Jan 2017 14:20:02 +0200
Subject: [PATCH 191/255] usb: xhci: use list_is_singular for cmd_list

Use list_is_singular() to check if cmd_list has only one entry.

[use list_empty() in queue command instead -Mathias]
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

(cherry picked from commit daa47f2132dce31fcab7c6ebdcb957e598c768f2)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
---
 drivers/usb/host/xhci-ring.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1428,7 +1428,7 @@ static void handle_cmd_completion(struct
 	}
 
 	/* restart timer if this wasn't the last command */
-	if (cmd->cmd_list.next != &xhci->cmd_list) {
+	if (!list_is_singular(&xhci->cmd_list)) {
 		xhci->current_cmd = list_entry(cmd->cmd_list.next,
 					       struct xhci_command, cmd_list);
 		xhci_mod_cmd_timer(xhci, XHCI_CMD_DEFAULT_TIMEOUT);
@@ -3805,14 +3805,15 @@ static int queue_command(struct xhci_hcd
 	}
 
 	cmd->command_trb = xhci->cmd_ring->enqueue;
-	list_add_tail(&cmd->cmd_list, &xhci->cmd_list);
 
 	/* if there are no other commands queued we start the timeout timer */
-	if (xhci->cmd_list.next == &cmd->cmd_list) {
+	if (list_empty(&xhci->cmd_list)) {
 		xhci->current_cmd = cmd;
 		xhci_mod_cmd_timer(xhci, XHCI_CMD_DEFAULT_TIMEOUT);
 	}
 
+	list_add_tail(&cmd->cmd_list, &xhci->cmd_list);
+
 	queue_trb(xhci, xhci->cmd_ring, false, field1, field2, field3,
 			field4 | xhci->cmd_ring->cycle_state);
 	return 0;