Commit Graph

12 Commits

Author SHA1 Message Date
Fuqian Huang
3114bc89c0 usb: host: Remove call to memset after dma_alloc_coherent
In commit 518a2f1925
("dma-mapping: zero memory returned from dma_alloc_*"),
dma_alloc_coherent has already zeroed the memory.
So memset is not needed.

Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
Link: https://lore.kernel.org/r/20190715032010.7258-1-huangfq.daxian@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-25 11:10:54 +02:00
Will Deacon
fb24ea52f7 drivers: Remove explicit invocations of mmiowb()
mmiowb() is now implied by spin_unlock() on architectures that require
it, so there is no reason to call it from driver code. This patch was
generated using coccinelle:

	@mmiowb@
	@@
	- mmiowb();

and invoked as:

$ for d in drivers include/linux/qed sound; do \
spatch --include-headers --sp-file mmiowb.cocci --dir $d --in-place; done

NOTE: mmiowb() has only ever guaranteed ordering in conjunction with
spin_unlock(). However, pairing each mmiowb() removal in this patch with
the corresponding call to spin_unlock() is not at all trivial, so there
is a small chance that this change may regress any drivers incorrectly
relying on mmiowb() to order MMIO writes between CPUs using lock-free
synchronisation. If you've ended up bisecting to this commit, you can
reintroduce the mmiowb() calls using wmb() instead, which should restore
the old behaviour on all architectures other than some esoteric ia64
systems.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-08 12:01:02 +01:00
Mathias Nyman
8867ea2621 usb: xhci: dbc: Don't free all memory with spinlock held
The xhci debug capability (DbC) feature did its memory cleanup with
spinlock held. dma_free_coherent() warns if called with interrupts
disabled

move the memory cleanup outside the spinlock

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-22 17:16:05 +01:00
Prabhat Chand Pandey
ea5cc92517 usb: xhci: dbc: Fixing typo error.
Replaced "xhci_dbc_flush_reqests" with xhci_dbc_flush_requests".

Signed-off-by: Prabhat Chand Pandey <prabhat.chand.pandey@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-20 20:18:23 +01:00
Greg Kroah-Hartman
500f0716b5 Merge 4.18-rc5 into usb-next
We need the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-16 09:09:24 +02:00
Colin Ian King
6c7dbe3619 usb: xhci: dbc: remove redundant pointer dbc
Pointer dbc is being assigned but is never used hence it is
redundant and can be removed.

Cleans up clang warning:
variable 'dbc' set but not used [-Wunused-but-set-variable]

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-13 15:41:56 +02:00
Kai-Heng Feng
74cb319bd9 usb: xhci: dbc: Don't decrement runtime PM counter if DBC is not started
pm_runtime_put_sync() gets called everytime in xhci_dbc_stop().

If dbc is not started, this makes the runtime PM counter incorrectly
becomes 0, and calls autosuspend function. Then we'll keep seeing this:
[54664.762220] xhci_hcd 0000:00:14.0: Root hub is not suspended

So only calls pm_runtime_put_sync() when dbc was started.

Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-02 17:19:27 +02:00
Lu Baolu
4786d2ef45 usb: xhci: dbc: Add SPDX identifiers to dbc files
Update the xhci dbc files with the correct SPDX license identifiers.

Fixes: dfba2174dc ("usb: xhci: Add DbC support in xHCI driver")
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexB.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-24 18:03:07 +02:00
Lu Baolu
a098dc8b03 usb: xhci: dbc: Fix lockdep warning
The xHCI DbC implementation might enter a deadlock situation because
there is no sufficient protection against the shared data between
process and softirq contexts. This can lead to the following lockdep
warnings. This patch changes to use spin_{,un}lock_irq{save,restore}
to avoid potential deadlock.

[ 528.248084] ================================
[ 528.252914] WARNING: inconsistent lock state
[ 528.257756] 4.15.0-rc1+ #1630 Not tainted
[ 528.262305] --------------------------------
[ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes:
[ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0
[ 528.290043] {SOFTIRQ-ON-W} state was registered at:
[ 528.295570] _raw_spin_lock+0x2f/0x40
[ 528.299818] dbc_write_complete+0x27/0xa0
[ 528.304458] xhci_dbc_giveback+0xd1/0x200
[ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70
[ 528.315116] xhci_dbc_handle_events+0x696/0x7b0
[ 528.320349] process_one_work+0x1ee/0x6e0
[ 528.324988] worker_thread+0x4a/0x430
[ 528.329236] kthread+0x13e/0x170
[ 528.332992] ret_from_fork+0x24/0x30
[ 528.337141] irq event stamp: 2861
[ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250
[ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40
[ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9
[ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60
[ 528.379048]
[ 528.379048] other info that might help us debug this:
[ 528.386443] Possible unsafe locking scenario:
[ 528.386443]
[ 528.393150] CPU0
[ 528.395917] ----
[ 528.398687] lock(&(&port->port_lock)->rlock);
[ 528.403821] <Interrupt>
[ 528.406786] lock(&(&port->port_lock)->rlock);
[ 528.412116]
[ 528.412116] *** DEADLOCK ***
[ 528.412116]
[ 528.418825] no locks held by ksoftirqd/1/17.
[ 528.423662]
[ 528.423662] stack backtrace:
[ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630
[ 528.436387] Call Trace:
[ 528.439158] dump_stack+0x5e/0x8e
[ 528.442914] print_usage_bug+0x1fc/0x220
[ 528.447357] mark_lock+0x4db/0x5a0
[ 528.451210] __lock_acquire+0x726/0x1130
[ 528.455655] ? __lock_acquire+0x557/0x1130
[ 528.460296] lock_acquire+0xa2/0x200
[ 528.464347] ? dbc_rx_push+0x38/0x1c0
[ 528.468496] _raw_spin_lock_irq+0x35/0x40
[ 528.473038] ? dbc_rx_push+0x38/0x1c0
[ 528.477186] dbc_rx_push+0x38/0x1c0
[ 528.481139] tasklet_action+0x1d2/0x250
[ 528.485483] __do_softirq+0x1dc/0x4f9
[ 528.489630] run_ksoftirqd+0x1b/0x60
[ 528.493682] smpboot_thread_fn+0x179/0x270
[ 528.498324] kthread+0x13e/0x170
[ 528.501981] ? sort_range+0x20/0x20
[ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80
[ 528.511755] ret_from_fork+0x24/0x30

Fixes: dfba2174dc ("usb: xhci: Add DbC support in xHCI driver")
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>
2018-03-08 09:06:53 -08:00
Greg Kroah-Hartman
ed5bd7a47f USB: move many drivers to use DEVICE_ATTR_RW
Instead of "open coding" a DEVICE_ATTR() define, use the
DEVICE_ATTR_RW() macro instead, which does everything properly instead.

This does require a few static functions to be renamed to work properly,
but thanks to a script from Joe Perches, this was easily done.

Reported-by: Joe Perches <joe@perches.com>
Cc: Matthieu CASTET <castet.matthieu@free.fr>
Cc: Stanislaw Gruszka <stf_xl@wp.pl>
Cc: Peter Chen <Peter.Chen@nxp.com>
Cc: Mathias Nyman <mathias.nyman@intel.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-24 08:49:51 +01:00
Mathias Nyman
33369d5a20 xhci: fixup incorrect memset size parameter when clearing up DbC on exit.
Incorrect size was given to memset when zeroing the DbC endpoint
structures on exit. Use element size * ARRAY_SIZE to fix it

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Fixes: dfba2174dc ("usb: xhci: Add DbC support in xHCI driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-12 13:16:07 +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