Commit Graph

365 Commits

Author SHA1 Message Date
Mathias Nyman
f5249461b5 xhci: Clear the host side toggle manually when endpoint is soft reset
Some devices use a clear endpoint halt request as a soft reset, even if
the endpoint is not halted. This will clear the toggle and sequence on the
device side.

xHCI however refuses to reset a non-halted endpoint, so instead
we need to issue a configure endpoint command on xHCI to clear its host
side toggle and sequence, and get it in sync with the device side.

This is a respin of a old patch that was reverted as it had a stale
endpoint context dequeue value which caused regression.
commit 27082e2654 ("xhci: Clear the host side toggle manually when
endpoint is 'soft reset'")

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-16 15:40:19 +01:00
Mathias Nyman
15febf5eed xhci: refactor xhci_urb_enqueue a bit with minor changes
make the local ep_state variable a pointer to the actual ring ep_state.
This allows us to read fresh ep_state values every time, will be useful
later.

Also move the streams check out from bulk only case. Even if only
bulk tranfers can use streams we shouldn't continue if those flags
are set. Main reason for this change is really code readability and
grouping functionality

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-16 15:40:18 +01:00
Zhengjun Xing
11cd764dc9 xhci: fix xhci debugfs errors in xhci_stop
In function xhci_stop, xhci_debugfs_exit called before xhci_mem_cleanup.
xhci_debugfs_exit removed the xhci debugfs root nodes, xhci_mem_cleanup
called function xhci_free_virt_devices_depth_first which in turn called
function xhci_debugfs_remove_slot.
Function xhci_debugfs_remove_slot removed the nodes for devices, the nodes
folders are sub folder of xhci debugfs.

It is unreasonable to remove xhci debugfs root folder before
xhci debugfs sub folder. Function xhci_mem_cleanup should be called
before function xhci_debugfs_exit.

Fixes: 02b6fdc2a1 ("usb: xhci: Add debugfs interface for xHCI driver")
Cc: <stable@vger.kernel.org> # v4.15
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-15 18:36:19 +01:00
Zhengjun Xing
8c5a93ebf7 xhci: xhci debugfs device nodes weren't removed after device plugged out
There is a bug after plugged out USB device, the device and its ep00
nodes are still kept, we need to remove the nodes in xhci_free_dev when
USB device is plugged out.

Fixes: 052f71e25a ("xhci: Fix xhci debugfs NULL pointer dereference in resume from hibernate")
Cc: <stable@vger.kernel.org> # v4.15
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-15 18:36:19 +01:00
Zhengjun Xing
d916767172 xhci: Fix xhci debugfs devices node disappearance after hibernation
During system resume from hibernation, xhci host is reset, all the
nodes in devices folder are removed in xhci_mem_cleanup function.
Later nodes in /sys/kernel/debug/usb/xhci/* are created again in
function xhci_run, but the nodes already exist, so the nodes still
keep the old ones, finally device nodes in xhci debugfs folder
/sys/kernel/debug/usb/xhci/*/devices/* are disappeared.

This fix removed xhci debugfs nodes before the nodes are re-created,
so all the nodes in xhci debugfs can be re-created successfully.

Fixes: 02b6fdc2a1 ("usb: xhci: Add debugfs interface for xHCI driver")
Cc: <stable@vger.kernel.org> # v4.15
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-15 18:36:19 +01:00
Greg Kroah-Hartman
01f1918833 Merge 4.15.0-rc6 into usb-next
We want the USB fixes in here, and this resolves a merge issue with the
vhci_rx.c file.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02 15:13:41 +01:00
Mathias Nyman
052f71e25a xhci: Fix xhci debugfs NULL pointer dereference in resume from hibernate
Free the virt_device and its debugfs_private member together.

When resuming from hibernate the .free_dev callback unconditionally
freed the debugfs_private member, but could leave virt_device intact.

This triggered a NULL pointer dereference after resume when usbmuxd
sent a USBDEVFS_SETCONFIGURATION ioctl to a device, trying to add a
endpoint debugfs entry to a already freed debugfs_private pointer.

Fixes: 02b6fdc2a1 ("usb: xhci: Add debugfs interface for xHCI driver")
Reported-by: Alexander Kappner <agk@godking.net>
Tested-by: Alexander Kappner <agk@godking.net>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-27 15:24:27 +01:00
Adam Wallis
ab725cbec3 usb: xhci: allow imod-interval to be configurable
The xHCI driver currently has the IMOD set to 160, which
translates to an IMOD interval of 40,000ns (160 * 250)ns

Commit 0cbd4b34cd ("xhci: mediatek: support MTK xHCI host controller")
introduced a QUIRK for the MTK platform to adjust this interval to 20,
which translates to an IMOD interval of 5,000ns (20 * 250)ns. This is
due to the fact that the MTK controller IMOD interval is 8 times
as much as defined in xHCI spec.

Instead of adding more quirk bits for additional platforms, this patch
introduces the ability for vendors to set the IMOD_INTERVAL as is
optimal for their platform. By using device_property_read_u32() on
"imod-interval-ns", the IMOD INTERVAL can be specified in nano seconds.
If no interval is specified, the default of 40,000ns (IMOD=160) will be
used.

No bounds checking has been implemented due to the fact that a vendor
may have violated the spec and would need to specify a value outside of
the max 8,000 IRQs/second limit specified in the xHCI spec.

Tested-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-08 17:43:52 +01:00
Lu Baolu
3054ea45fb usb: xhci: Cleanup printk debug message for ERST
Each event segment has been exposed through debugfs. There is no
need to dump ERST content with printk in code. Remove it to make
code more concise and readable.

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>
2017-12-08 17:43:52 +01:00
Lu Baolu
4c116cb138 usb: xhci: Cleanup printk debug message for registers
The content of each register has been exposed through debugfs.
There is no need to dump register content with printk in code
lines. Remove them to make code more concise and readable.

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>
2017-12-08 17:43:52 +01:00
Lu Baolu
dfba2174dc usb: xhci: Add DbC support in xHCI driver
xHCI compatible USB host controllers(i.e. super-speed USB3 controllers)
can be implemented with the Debug Capability(DbC). It presents a debug
device which is fully compliant with the USB framework and provides the
equivalent of a very high performance full-duplex serial link. The debug
capability operation model and registers interface are defined in 7.6.8
of the xHCI specification, revision 1.1.

The DbC debug device shares a root port with the xHCI host. By default,
the debug capability is disabled and the root port is assigned to xHCI.
When the DbC is enabled, the root port will be assigned to the DbC debug
device, and the xHCI sees nothing on this port. This implementation uses
a sysfs node named <dbc> under the xHCI device to manage the enabling
and disabling of the debug capability.

When the debug capability is enabled, it will present a debug device
through the debug port. This debug device is fully compliant with the
USB3 framework, and it can be enumerated by a debug host on the other
end of the USB link. As soon as the debug device is configured, a TTY
serial device named /dev/ttyDBC0 will be created.

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>
2017-12-08 17:43:52 +01:00
Mathias Nyman
103afda0e6 xhci: remove unnecessary boolean parameter from xhci_alloc_command
commands with input contexts are allocated with the
xhci_alloc_command_with_ctx helper.

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-08 17:43:52 +01:00
Mathias Nyman
14d49b7a0b xhci: add helper to allocate command with input context
Add a xhci_alloc_command_with_ctx() helper to get rid of
one of the boolean parameters telling if a context should
be allocated with the command.

No functional changes, improves core readability

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-08 17:43:52 +01:00
Corentin Labbe
bed53019d9 usb: xhci: remove unused variable ep
Fix the build warning: variable 'ep' set but not used

Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-08 17:43:52 +01:00
Corentin Labbe
78a0db2a61 usb: xhci: remove unused variable last_freed_endpoint
Fix the build warning about variable 'last_freed_endpoint'
set but not used [-Wunused-but-set-variable]

Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-08 17:43:51 +01:00
Kees Cook
e99e88a9d2 treewide: setup_timer() -> timer_setup()
This converts all remaining cases of the old setup_timer() API into using
timer_setup(), where the callback argument is the structure already
holding the struct timer_list. These should have no behavioral changes,
since they just change which pointer is passed into the callback with
the same available pointers after conversion. It handles the following
examples, in addition to some other variations.

Casting from unsigned long:

    void my_callback(unsigned long data)
    {
        struct something *ptr = (struct something *)data;
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, ptr);

and forced object casts:

    void my_callback(struct something *ptr)
    {
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr);

become:

    void my_callback(struct timer_list *t)
    {
        struct something *ptr = from_timer(ptr, t, my_timer);
    ...
    }
    ...
    timer_setup(&ptr->my_timer, my_callback, 0);

Direct function assignments:

    void my_callback(unsigned long data)
    {
        struct something *ptr = (struct something *)data;
    ...
    }
    ...
    ptr->my_timer.function = my_callback;

have a temporary cast added, along with converting the args:

    void my_callback(struct timer_list *t)
    {
        struct something *ptr = from_timer(ptr, t, my_timer);
    ...
    }
    ...
    ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback;

And finally, callbacks without a data assignment:

    void my_callback(unsigned long data)
    {
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, 0);

have their argument renamed to verify they're unused during conversion:

    void my_callback(struct timer_list *unused)
    {
    ...
    }
    ...
    timer_setup(&ptr->my_timer, my_callback, 0);

The conversion is done with the following Coccinelle script:

spatch --very-quiet --all-includes --include-headers \
	-I ./arch/x86/include -I ./arch/x86/include/generated \
	-I ./include -I ./arch/x86/include/uapi \
	-I ./arch/x86/include/generated/uapi -I ./include/uapi \
	-I ./include/generated/uapi --include ./include/linux/kconfig.h \
	--dir . \
	--cocci-file ~/src/data/timer_setup.cocci

@fix_address_of@
expression e;
@@

 setup_timer(
-&(e)
+&e
 , ...)

// Update any raw setup_timer() usages that have a NULL callback, but
// would otherwise match change_timer_function_usage, since the latter
// will update all function assignments done in the face of a NULL
// function initialization in setup_timer().
@change_timer_function_usage_NULL@
expression _E;
identifier _timer;
type _cast_data;
@@

(
-setup_timer(&_E->_timer, NULL, _E);
+timer_setup(&_E->_timer, NULL, 0);
|
-setup_timer(&_E->_timer, NULL, (_cast_data)_E);
+timer_setup(&_E->_timer, NULL, 0);
|
-setup_timer(&_E._timer, NULL, &_E);
+timer_setup(&_E._timer, NULL, 0);
|
-setup_timer(&_E._timer, NULL, (_cast_data)&_E);
+timer_setup(&_E._timer, NULL, 0);
)

@change_timer_function_usage@
expression _E;
identifier _timer;
struct timer_list _stl;
identifier _callback;
type _cast_func, _cast_data;
@@

(
-setup_timer(&_E->_timer, _callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, &_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, &_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)&_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, &_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, &_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
 _E->_timer@_stl.function = _callback;
|
 _E->_timer@_stl.function = &_callback;
|
 _E->_timer@_stl.function = (_cast_func)_callback;
|
 _E->_timer@_stl.function = (_cast_func)&_callback;
|
 _E._timer@_stl.function = _callback;
|
 _E._timer@_stl.function = &_callback;
|
 _E._timer@_stl.function = (_cast_func)_callback;
|
 _E._timer@_stl.function = (_cast_func)&_callback;
)

// callback(unsigned long arg)
@change_callback_handle_cast
 depends on change_timer_function_usage@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _origtype;
identifier _origarg;
type _handletype;
identifier _handle;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *t
 )
 {
(
	... when != _origarg
	_handletype *_handle =
-(_handletype *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle =
-(void *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle;
	... when != _handle
	_handle =
-(_handletype *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle;
	... when != _handle
	_handle =
-(void *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
)
 }

// callback(unsigned long arg) without existing variable
@change_callback_handle_cast_no_arg
 depends on change_timer_function_usage &&
                     !change_callback_handle_cast@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _origtype;
identifier _origarg;
type _handletype;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *t
 )
 {
+	_handletype *_origarg = from_timer(_origarg, t, _timer);
+
	... when != _origarg
-	(_handletype *)_origarg
+	_origarg
	... when != _origarg
 }

// Avoid already converted callbacks.
@match_callback_converted
 depends on change_timer_function_usage &&
            !change_callback_handle_cast &&
	    !change_callback_handle_cast_no_arg@
identifier change_timer_function_usage._callback;
identifier t;
@@

 void _callback(struct timer_list *t)
 { ... }

// callback(struct something *handle)
@change_callback_handle_arg
 depends on change_timer_function_usage &&
	    !match_callback_converted &&
            !change_callback_handle_cast &&
            !change_callback_handle_cast_no_arg@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _handletype;
identifier _handle;
@@

 void _callback(
-_handletype *_handle
+struct timer_list *t
 )
 {
+	_handletype *_handle = from_timer(_handle, t, _timer);
	...
 }

// If change_callback_handle_arg ran on an empty function, remove
// the added handler.
@unchange_callback_handle_arg
 depends on change_timer_function_usage &&
	    change_callback_handle_arg@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _handletype;
identifier _handle;
identifier t;
@@

 void _callback(struct timer_list *t)
 {
-	_handletype *_handle = from_timer(_handle, t, _timer);
 }

// We only want to refactor the setup_timer() data argument if we've found
// the matching callback. This undoes changes in change_timer_function_usage.
@unchange_timer_function_usage
 depends on change_timer_function_usage &&
            !change_callback_handle_cast &&
            !change_callback_handle_cast_no_arg &&
	    !change_callback_handle_arg@
expression change_timer_function_usage._E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type change_timer_function_usage._cast_data;
@@

(
-timer_setup(&_E->_timer, _callback, 0);
+setup_timer(&_E->_timer, _callback, (_cast_data)_E);
|
-timer_setup(&_E._timer, _callback, 0);
+setup_timer(&_E._timer, _callback, (_cast_data)&_E);
)

// If we fixed a callback from a .function assignment, fix the
// assignment cast now.
@change_timer_function_assignment
 depends on change_timer_function_usage &&
            (change_callback_handle_cast ||
             change_callback_handle_cast_no_arg ||
             change_callback_handle_arg)@
expression change_timer_function_usage._E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type _cast_func;
typedef TIMER_FUNC_TYPE;
@@

(
 _E->_timer.function =
-_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-(_cast_func)_callback;
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-(_cast_func)&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-&_callback;
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-(_cast_func)_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-(_cast_func)&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
)

// Sometimes timer functions are called directly. Replace matched args.
@change_timer_function_calls
 depends on change_timer_function_usage &&
            (change_callback_handle_cast ||
             change_callback_handle_cast_no_arg ||
             change_callback_handle_arg)@
expression _E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type _cast_data;
@@

 _callback(
(
-(_cast_data)_E
+&_E->_timer
|
-(_cast_data)&_E
+&_E._timer
|
-_E
+&_E->_timer
)
 )

// If a timer has been configured without a data argument, it can be
// converted without regard to the callback argument, since it is unused.
@match_timer_function_unused_data@
expression _E;
identifier _timer;
identifier _callback;
@@

(
-setup_timer(&_E->_timer, _callback, 0);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, 0L);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, 0UL);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0L);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0UL);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0L);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0UL);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0);
+timer_setup(_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0L);
+timer_setup(_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0UL);
+timer_setup(_timer, _callback, 0);
)

@change_callback_unused_data
 depends on match_timer_function_unused_data@
identifier match_timer_function_unused_data._callback;
type _origtype;
identifier _origarg;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *unused
 )
 {
	... when != _origarg
 }

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:07 -08:00
Greg Kroah-Hartman
9ed64195e3 USB: host: xhci: Remove redundant license text
Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner.  So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07 15:45:02 +01:00
Greg Kroah-Hartman
5fd54ace47 USB: add SPDX identifiers to all remaining files in drivers/usb/
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04 11:48:02 +01:00
Gustavo A. R. Silva
7d86499981 usb: host: xhci: mark expected switch fall-through
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 17:02:15 +01:00
Greg Kroah-Hartman
0520d37bb3 Merge 4.14-rc6 into usb-next
We need the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-23 14:24:37 +02:00
Mathias Nyman
ea7d0d6942 xhci: Identify USB 3.1 capable hosts by their port protocol capability
Many USB 3.1 capable hosts never updated the Serial Bus Release Number
(SBRN) register to USB 3.1 from USB 3.0

xhci driver identified USB 3.1 capable hosts based on this SBRN register,
which according to specs "contains the release of the Universal Serial
Bus Specification with which this Universal Serial Bus Host Controller
module is compliant." but still in october 2017 gives USB 3.0 as
the only possible option.

Make an additional check for USB 3.1 support and enable it if the xHCI
supported protocol capablity lists USB 3.1 capable ports.

Cc: <stable@vger.kernel.org> # v4.6+
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-17 10:38:12 +02:00
Greg Kroah-Hartman
4fcae770f3 Merge 4.14-rc4 into usb-next
This merges in the USB fixes that we need here.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-09 09:11:09 +02:00
Mathias Nyman
e3a78ff022 xhci: trace slot context when calling xhci_configure_endpoint()
Add trace showing content of input slot context for
configure endpoint and evaluate context commands

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 11:01:58 +02:00
Lu Baolu
651aaf36a7 usb: xhci: Handle USB transaction error on address command
Xhci driver handles USB transaction errors on transfer events,
but transaction errors are possible on address device command
completion events as well.

The xHCI specification (section 4.6.5) says: A USB Transaction
Error Completion Code for an Address Device Command may be due
to a Stall response from a device. Software should issue a Disable
Slot Command for the Device Slot then an Enable Slot Command to
recover from this error.

This patch handles USB transaction errors on address command
completion events. The related discussion threads can be found
through below links.

http://marc.info/?l=linux-usb&m=149362010728921&w=2
http://marc.info/?l=linux-usb&m=149252752825755&w=2

Suggested-by: Mathias Nyman <mathias.nyman@linux.intel.com>
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>
2017-10-05 11:01:58 +02:00
Lu Baolu
089ed4904e usb: xhci: Remove xhci->mutex from xhci_alloc_dev()
xhci->mutex was added in xhci_alloc_dev()  to protect two race sources
(xhci->slot_id and xhci->addr_dev) by commit a00918d052 ("usb: host:
xhci: add mutex for non-thread-safe data").

While xhci->slot_id has been discarded in commit c2d3d49bba ("usb:
xhci: move slot_id from xhci_hcd to xhci_command structure"), and
xhci->addr_dev has been removed in commit 87e44f2aac ("usb: xhci:
remove the use of xhci->addr_dev"), it's now safe to remove the use of
xhci->mutex in xhci_alloc_dev().

Link: https://marc.info/?l=linux-usb&m=150306294725821&w=2

Suggested-by: Mathias Nyman <mathias.nyman@linux.intel.com>
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>
2017-10-05 11:01:58 +02:00
Lu Baolu
dcabc76fa9 usb: xhci: Return error when host is dead in xhci_disable_slot()
xhci_disable_slot() is a helper for disabling a slot when a device
goes away or recovers from error situations. Currently, it returns
success when it sees a dead host. This is not the right way to go.
It should return error and let the invoker know that disable slot
command was failed due to a dead host.

Fixes: f9e609b824 ("usb: xhci: Add helper function xhci_disable_slot().")
Cc: Guoqing Zhang <guoqing.zhang@intel.com>
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>
2017-10-05 11:01:58 +02:00
Lu Baolu
11ec7588a1 usb: xhci: Fix memory leak when xhci_disable_slot() returns error
If xhci_disable_slot() returns success, a disable slot command
trb was queued in the command ring. The command completion
handler will free the virtual device data structure associated
with the slot. On the other hand, when xhci_disable_slot()
returns error, the invokers should take the responsibilities to
free the slot related data structure. Otherwise, memory leakage
happens.

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>
2017-10-05 11:01:58 +02:00
Lu Baolu
cd3f1790b0 usb: xhci: Fix potential memory leak in xhci_disable_slot()
xhci_disable_slot() allows the invoker to pass a command pointer
as paramenter. Otherwise, it will allocate one. This will cause
memory leak when a command structure was allocated inside of this
function while queuing command trb fails. Another problem comes up
when the invoker passed a command pointer, but xhci_disable_slot()
frees it when it detects a dead host.

This patch fixes these two problems by removing the command parameter
from xhci_disable_slot().

Fixes: f9e609b824 ("usb: xhci: Add helper function xhci_disable_slot().")
Cc: Guoqing Zhang <guoqing.zhang@intel.com>
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>
2017-10-05 11:01:57 +02:00
Lu Baolu
b64149ca01 usb: xhci: Disable slot even when virt-dev is null
xhci_disable_slot() is a helper for disabling a slot when a device
goes away or recovers from error situations. Currently, it checks
the corespoding virt-dev pointer and returns directly (w/o issuing
disable slot command) if it's null.

This is unnecessary and will cause problems in case where virt-dev
allocation fails and xhci_disable_slot() is called to roll back the
hardware state. Refer to the implementation of xhci_alloc_dev().

This patch removes lines to check virt-dev in xhci_disable_slot().

Fixes: f9e609b824 ("usb: xhci: Add helper function xhci_disable_slot().")
Cc: Guoqing Zhang <guoqing.zhang@intel.com>
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>
2017-10-05 11:01:57 +02:00
Lu Baolu
02b6fdc2a1 usb: xhci: Add debugfs interface for xHCI driver
This adds debugfs consumer for xHCI driver. The debugfs entries
read all host registers, device/endpoint contexts, command ring,
event ring and various endpoint rings. With these entries, users
can check the registers and memory spaces used by a host during
run time, or save all the information with a simple 'cp -r' for
post-mortem programs.

The file hierarchy looks like this.

[root of debugfs]
|__usb
|____[e,u,o]hci                 <---------[root for other HCIs]
|____xhci                       <---------------[root for xHCI]
|______0000:00:14.0             <--------------[xHCI host name]
|________reg-cap                <--------[capability registers]
|________reg-op                 <-------[operational registers]
|________reg-runtime            <-----------[runtime registers]
|________reg-ext-#cap_name      <----[extended capability regs]
|________command-ring           <-------[root for command ring]
|__________cycle                <------------------[ring cycle]
|__________dequeue              <--------[ring dequeue pointer]
|__________enqueue              <--------[ring enqueue pointer]
|__________trbs                 <-------------------[ring trbs]
|________event-ring             <---------[root for event ring]
|__________cycle                <------------------[ring cycle]
|__________dequeue              <--------[ring dequeue pointer]
|__________enqueue              <--------[ring enqueue pointer]
|__________trbs                 <-------------------[ring trbs]
|________devices                <------------[root for devices]
|__________#slot_id             <-----------[root for a device]
|____________name               <-----------------[device name]
|____________slot-context       <----------------[slot context]
|____________ep-context         <-----------[endpoint contexts]
|____________ep#ep_index        <--------[root for an endpoint]
|______________cycle            <------------------[ring cycle]
|______________dequeue          <--------[ring dequeue pointer]
|______________enqueue          <--------[ring enqueue pointer]
|______________trbs             <-------------------[ring trbs]

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>
2017-10-05 11:01:57 +02:00
Thang Q. Nguyen
4750bc78ef usb: host: xhci support option to disable the xHCI USB2 HW LPM
XHCI specification 1.1 does not require xHCI-compliant controllers
to always enable hardware USB2 LPM. However, the current xHCI
driver always enable it when seeing HLC=1.
This patch supports an option for users to control disabling
USB2 Hardware LPM via DT/ACPI attribute.
This option is needed in case user would like to disable this
feature. For example, their xHCI controller has its USB2 HW LPM
broken.

Signed-off-by: Tung Nguyen <tunguyen@apm.com>
Signed-off-by: Thang Q. Nguyen <tqnguyen@apm.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 11:01:57 +02:00
Lu Baolu
9821786d7c usb: xhci: Free the right ring in xhci_add_endpoint()
In the xhci_add_endpoint(), a new ring was allocated and saved at
xhci_virt_ep->new_ring. Hence, when error happens, we need to free
the allocated ring before returning error.

Current code frees xhci_virt_ep->ring instead of the new_ring. This
patch fixes this.

Cc: <stable@vger.kernel.org>
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>
2017-09-18 17:10:40 +02:00
Shu Wang
d6f5f071f1 xhci: fix memleak in xhci_run()
Found this issue by kmemleak.
xhci_run() did not check return val and free command for
xhci_queue_vendor_command()

unreferenced object 0xffff88011c0be500 (size 64):
  comm "kworker/0:1", pid 58, jiffies 4294670908 (age 50.420s)
  hex dump (first 32 bytes):
  backtrace:
    [<ffffffff8176166a>] kmemleak_alloc+0x4a/0xa0
    [<ffffffff8121801a>] kmem_cache_alloc_trace+0xca/0x1d0
    [<ffffffff81576bf4>] xhci_alloc_command+0x44/0x130
    [<ffffffff8156f1cc>] xhci_run+0x4cc/0x630
    [<ffffffff8153b84b>] usb_add_hcd+0x3bb/0x950
    [<ffffffff8154eac8>] usb_hcd_pci_probe+0x188/0x500
    [<ffffffff815851ac>] xhci_pci_probe+0x2c/0x220
    [<ffffffff813d2ca5>] local_pci_probe+0x45/0xa0
    [<ffffffff810a54e4>] work_for_cpu_fn+0x14/0x20
    [<ffffffff810a8409>] process_one_work+0x149/0x360
    [<ffffffff810a8d08>] worker_thread+0x1d8/0x3c0
    [<ffffffff810ae7d9>] kthread+0x109/0x140
    [<ffffffff8176d585>] ret_from_fork+0x25/0x30
    [<ffffffffffffffff>] 0xffffffffffffffff

Cc: <stable@vger.kernel.org>
Signed-off-by: Shu Wang <shuwang@redhat.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-20 14:40:36 +02:00
Jiahau Chang
9da5a1092b xhci: Bad Ethernet performance plugged in ASM1042A host
When USB Ethernet is plugged in ASMEDIA ASM1042A xHCI host, bad
performance was manifesting in Web browser use (like download
large file such as ISO image). It is known limitation of
ASM1042A that is not compatible with driver scheduling,
As a workaround we can modify flow control handling of ASM1042A.
The register we modify is changes the behavior

[use quirk bit 28, usleep_range 40-60us, empty non-pci function -Mathias]
Cc: <stable@vger.kernel.org>
Signed-off-by: Jiahau Chang <Lars_chang@asmedia.com.tw>
Signed-off-by: Ian Pilcher <arequipeno@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-20 14:40:35 +02:00
Mathias Nyman
d36374fdfb xhci: cleanup virtual endoint structure, remove stopped_stream
Get rid of stopped_stream member in virtual endpoint structure as
it is only used in one case when cleaning a halted endpoint.

Pass it as function parameter instead.

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman
c5628a2af8 xhci: remove endpoint ring cache
Anurag Kumar Vulisha reported several issues with xhci endpoint
ring caching.

31 Rings are cached per device before a ring is freed.
These cached rings are not used as default if a new ring is needed.
They are only used if the driver fails to allocate memory for a ring.

The current ring cache is more a reason to why we run out memory than a
help when we actually do so.

Anurag Kumar Vulisha tried to use cached rings as a first option and
found new issues with cached ring initialization.
Cached rings were first zeroed and then manually reinitialized with link
trbs etc, but forgetting to set some important bits like cycle toggle bit.

Remove the ring cache completely as it's a faulty premature optimization
eating memory

Reported-by: Anurag Kumar Vulisha <anuragku@xilinx.com>
Tested-by: Anurag Kumar Vulisha <anuragku@xilinx.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman
8790736dbf xhci: Add stream id to xhci_dequeue_state structure
The values for the new dequeue segment, new dequeue pointer and new cycle
state are needed for manually moving the xHC ring dequeue pointer.
These are conveniently stored in a xhci_dequeue_state structure.

stream support was added later and stream_id was carried
as a function parameter.

Move the stream_id to the xhci_dequeue_state structure instead.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 18:02:58 +09:00
Mathias Nyman
604d02a2a6 xhci: Fix command ring stop regression in 4.11
In 4.11 TRB completion codes were renamed to match spec.

Completion codes for command ring stopped and endpoint stopped
were mixed, leading to failures while handling a stopped command ring.

Use the correct completion code for command ring stopped events.

Fixes: 0b7c105a04 ("usb: host: xhci: rename completion codes to match spec")
Cc: <stable@vger.kernel.org> # 4.11
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 15:19:42 +02:00
Peter Chen
6a29beef9d usb: host: xhci-ring: don't need to clear interrupt pending for MSI enabled hcd
According to xHCI spec Figure 30: Interrupt Throttle Flow Diagram

	If PCI Message Signaled Interrupts (MSI or MSI-X) are enabled,
       	then the assertion of the Interrupt Pending (IP) flag in Figure 30
       	generates a PCI Dword write. The IP flag is automatically cleared
       	by the completion of the PCI write.

the MSI enabled HCs don't need to clear interrupt pending bit, but
hcd->irq = 0 doesn't equal to MSI enabled HCD. At some Dual-role
controller software designs, it sets hcd->irq as 0 to avoid HCD
requesting interrupt, and they want to decide when to call usb_hcd_irq
by software.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 15:19:41 +02:00
Christoph Hellwig
77d45b4500 xhci: switch to pci_alloc_irq_vectors
Use the modern API to request MSI or MSI-X interrupts, which allows us to
get rid of the msix_entries array, as well as cleaning up the cleanup
code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-19 19:59:17 +02:00
Lu Baolu
c8844f2ddb usb: xhci: remove xhci_dbg_ctx()
XHCI context changes have already been traced by the trace
events. It's unnecessary to put the same message in kernel
log. This patch removes the use of xhci_dbg_ctx().

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>
2017-04-08 12:17:42 +02:00
Lu Baolu
121dcf1190 usb: xhci: remove ring debugging code
XHCI ring changes have already been traced by the ring trace
events. It's unnecessary to put the same messages in kernel
log. This patch removes the debugging code for a ring.

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>
2017-04-08 12:17:41 +02:00
Lu Baolu
74e0b5649c usb: xhci: remove error messages for failed memory allocation
Omit extra messages for memory allocation failure.

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>
2017-04-08 12:17:41 +02:00
Lu Baolu
3969384cf8 usb: xhci: make several functions static
Several functions have a single user in the same file where it
is defined. There's no need to expose it anywhere else.

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>
2017-04-08 12:17:41 +02:00
Mathias Nyman
d9f11ba9f1 xhci: Rework how we handle unresponsive or hoptlug removed hosts
Introduce a new xhci_hc_died() function that takes care of handling
pending commands and URBs if a host controller becomes unresponsive.

This addresses issues on hotpluggable xhci controllers that disappear
from the bus suddenly, often while the bus (PCI) remove function is
still being processed.

xhci_hc_died() sets a XHCI_STATUS_DYING flag to prevent new URBs and
commands or to be queued. The flag also ensures xhci_hc_died() will
give back pending commands and URBs once.

Host is considered dead if register read returns 0xffffffff, or host
fails to abort the command ring, or fails stopping an endpoint after
trying for 5 seconds.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Joel Stanley
fe190ed0d6 xhci: Do not halt the host until both HCD have disconnected their devices.
We can't halt the host controller immediately when first HCD is removed as
it will cause problems if we have devices attached to the second (primary)
HCD, like a keyboard.

We've been carrying this in our Linux-as-a-bootloader environment for a
little while now. The machines all have the same TI TUSB73x0 part,
and when we kexec the devices don't come back until a system power cycle.

[minor adjustments, code comments and remove HALT check  -Mathias]
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Felipe Balbi
19a7d0d65c usb: host: xhci: add Slot and EP Context tracers
With these, we can track what's happening with the HW while executing
each and every command. It will give us visibility into how the
different contexts are being modified by xHC which can bring insight
into problems while debugging.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Guoqing Zhang
26bba5c767 usb: xhci: Expose xhci_start() function.
Change the visability of xhci_start() so that it
can be used when enabling test mode.

Signed-off-by: Guoqing Zhang <guoqing.zhang@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:40 +02:00
Guoqing Zhang
f9e609b824 usb: xhci: Add helper function xhci_disable_slot().
Refactoring slot disable related code into a helper
function xhci_disable_slot() which can be used when
enabling test mode.

Signed-off-by: Guoqing Zhang <guoqing.zhang@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:40 +02:00
Lu Baolu
d1001ab410 usb: xhci: clear EINT bit in status correctly
EINT(Event Interrupt) is a write-1-to-clear type of bit in xhci
status register. It should be cleared by writing a 1. Writing 0
to this bit has no effect.

Xhci driver tries to clear this bit by writing 0 to it. This is
not the right way to go. This patch corrects this by reading the
register first, then clearing all RO/RW1C/RsvZ bits and setting
the clearing bit, and writing back the new value at last.

Xhci spec requires that software that uses EINT shall clear it
prior to clearing any IP flags in section 5.4.2. This is the
reason why this patch is CC'ed stable as well.

[old way didn't cause any issues, skip stable, send to next -Mathias]

Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
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>
2017-04-08 12:17:40 +02:00