[kernel/f21] xhci: Check if slot is already in default state before moving it there

[Justin M. Forbes]

commit aa7180f4aa2d1b3b1ad705be84cb39b9ee8da744
Author: Justin M. Forbes <jforbes at redhat.com>
Date:   Mon Jan 19 09:32:25 2015 -0600

    xhci: Check if slot is already in default state before moving it there

 kernel.spec                                        |    5 ++-
 ...check-if-slot-is-already-in-default-state.patch |   51 ++++++++++++++++++++
 2 files changed, 55 insertions(+), 1 deletions(-)
---
diff --git a/kernel.spec b/kernel.spec
index 3dbe43e..c536445 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -651,6 +651,7 @@ Patch30001: mpssd-x86-only.patch
 
 # Patches from 3.18.4 stable queue (should fix i915 issues)
 Patch30002: stable-3.18.4-queue.patch
+Patch30003: xhci-check-if-slot-is-already-in-default-state.patch
 
 # END OF PATCH DEFINITIONS
 
@@ -1407,7 +1408,8 @@ ApplyPatch acpi-video-Add-disable_native_backlight-quirk-for-Sa.patch
 ApplyPatch mpssd-x86-only.patch
 
 # Patches from 3.18.4 stable queue (should fix i915 issues)
-# ApplyPatch stable-3.18.4-queue.patch
+ApplyPatch stable-3.18.4-queue.patch
+ApplyPatch xhci-check-if-slot-is-already-in-default-state.patch
 
 %if 0%{?aarch64patches}
 ApplyPatch kernel-arm64.patch
@@ -2281,6 +2283,7 @@ fi
 %changelog
 * Mon Jan 19 2015 Justin M. Forbes <jforbes at fedoraproject.org> - 3.18.3-201
 - Add fixes from 3.18.4 queue to fix i915 issues (rhbz 1183232)
+- xhci: Check if slot is already in default state before moving it there (rhbz 1183289)
 
 * Fri Jan 16 2015 Justin M. Forbes <jforbes at fedoraproject.org> - 3.18.3-200
 - Linux v3.18.3
diff --git a/xhci-check-if-slot-is-already-in-default-state.patch b/xhci-check-if-slot-is-already-in-default-state.patch
new file mode 100644
index 0000000..ea8dee0
--- /dev/null
+++ b/xhci-check-if-slot-is-already-in-default-state.patch
@@ -0,0 +1,51 @@
+commit f161ead70fa6a62e432dff6e9dab8e3cfbeabea6
+Author: Mathias Nyman <mathias.nyman at linux.intel.com>
+Date:   Fri Jan 9 17:18:28 2015 +0200
+
+    xhci: Check if slot is already in default state before moving it there
+    
+    Solves xhci error cases with debug messages:
+    xhci_hcd 0000:00:14.0: Setup ERROR: setup context command for slot 1.
+    usb 1-6: hub failed to enable device, error -22
+    
+    xhci will give a context state error if we try to set a slot in default
+    state to the same default state with a special address device command.
+    
+    Turns out this happends in several cases:
+    - retry reading the device rescriptor in hub_port_init()
+    - usb_reset_device() is called for a slot in default state
+    - in resume path, usb_port_resume() calls hub_port_init()
+    
+    The default state is usually reached from most states with a reset device
+    command without any context state errors, but using the address device
+    command with BSA bit set (block set address) only works from the enabled
+    state and will otherwise cause context error.
+    
+    solve this by checking if we are already in the default state before issuing
+    a address device BSA=1 command.
+    
+    Fixes: 48fc7dbd52c0 ("usb: xhci: change enumeration scheme to 'new scheme'")
+    Cc: <stable at vger.kernel.org> # v3.14+
+    Signed-off-by: Mathias Nyman <mathias.nyman at linux.intel.com>
+    Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
+
+diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
+index 01fcbb5..c50d8d2 100644
+--- a/drivers/usb/host/xhci.c
++++ b/drivers/usb/host/xhci.c
+@@ -3803,6 +3803,15 @@ static int xhci_setup_device(struct usb_hcd *hcd, struct usb_device *udev,
+ 		return -EINVAL;
+ 	}
+
++	if (setup == SETUP_CONTEXT_ONLY) {
++		slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->out_ctx);
++		if (GET_SLOT_STATE(le32_to_cpu(slot_ctx->dev_state)) ==
++		    SLOT_STATE_DEFAULT) {
++			xhci_dbg(xhci, "Slot already in default state\n");
++			return 0;
++		}
++	}
++
+ 	command = xhci_alloc_command(xhci, false, false, GFP_KERNEL);
+ 	if (!command)
+ 		return -ENOMEM;