genirq: Fix irqfixup, irqpoll regression

commit c75d720fca8a91ce99196d33adea383621027bf2 upstream.

commit d05c65fff0 ("genirq: spurious: Run only one poller at a time")
introduced a regression, leaving the boot options 'irqfixup' and
'irqpoll' non-functional. The patch placed tests in each function, to
exit if the function is already running. The test in 'misrouted_irq'
exited when it should have proceeded, effectively disabling
'misrouted_irq' and 'poll_spurious_irqs'.

The check for an already running poller needs to be "!= 1" not "== 1"
as "1" is the value when the first poller starts running.

Signed-off-by: Edward Donovan <edward.donovan@numble.net>
Cc: maciej.rutecki@gmail.com
Link: http://lkml.kernel.org/r/1320175784-6745-1-git-send-email-edward.donovan@numble.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
fix WARNING: at drivers/scsi/scsi_lib.c:1704

commit 4e6c82b3614a18740ef63109d58743a359266daf upstream.

On Mon, 2011-11-07 at 17:24 +1100, Stephen Rothwell wrote:
> Hi all,
>
> Starting some time last week I am getting the following during boot on
> our PPC970 blade:
>
> calling  .ipr_init+0x0/0x68 @ 1
> ipr: IBM Power RAID SCSI Device Driver version: 2.5.2 (April 27, 2011)
> ipr 0000:01:01.0: Found IOA with IRQ: 26
> ipr 0000:01:01.0: Starting IOA initialization sequence.
> ipr 0000:01:01.0: Adapter firmware version: 06160039
> ipr 0000:01:01.0: IOA initialized.
> scsi0 : IBM 572E Storage Adapter
> ------------[ cut here ]------------
> WARNING: at drivers/scsi/scsi_lib.c:1704
> Modules linked in:
> NIP: c00000000053b3d4 LR: c00000000053e5b0 CTR: c000000000541d70
> REGS: c0000000783c2f60 TRAP: 0700   Not tainted  (3.1.0-autokern1)
> MSR: 8000000000029032 <EE,ME,CE,IR,DR>  CR: 24002024  XER: 20000002
> TASK = c0000000783b8000[1] 'swapper' THREAD: c0000000783c0000 CPU: 0
> GPR00: 0000000000000001 c0000000783c31e0 c000000000cf38b0 c00000000239a9d0
> GPR04: c000000000cbe8f8 0000000000000000 c0000000783c3040 0000000000000000
> GPR08: c000000075daf488 c000000078a3b7ff c000000000bcacc8 0000000000000000
> GPR12: 0000000044002028 c000000007ffb000 0000000002e40000 000000000099b800
> GPR16: 0000000000000000 c000000000bba5fc c000000000a61db8 0000000000000000
> GPR20: 0000000001b77200 0000000000000000 c000000078990000 0000000000000001
> GPR24: c000000002396828 0000000000000000 0000000000000000 c000000078a3b938
> GPR28: fffffffffffffffa c0000000008ad2c0 c000000000c7faa8 c00000000239a9d0
> NIP [c00000000053b3d4] .scsi_free_queue+0x24/0x90
> LR [c00000000053e5b0] .scsi_alloc_sdev+0x280/0x2e0
> Call Trace:
> [c0000000783c31e0] [c000000000c7faa8] wireless_seq_fops+0x278d0/0x2eb88 (unreliable)
> [c0000000783c3270] [c00000000053e5b0] .scsi_alloc_sdev+0x280/0x2e0
> [c0000000783c3330] [c00000000053eba0] .scsi_probe_and_add_lun+0x390/0xb40
> [c0000000783c34a0] [c00000000053f7ec] .__scsi_scan_target+0x16c/0x650
> [c0000000783c35f0] [c00000000053fd90] .scsi_scan_channel+0xc0/0x100
> [c0000000783c36a0] [c00000000053fefc] .scsi_scan_host_selected+0x12c/0x1c0
> [c0000000783c3750] [c00000000083dcb4] .ipr_probe+0x2c0/0x390
> [c0000000783c3830] [c0000000003f50b4] .local_pci_probe+0x34/0x50
> [c0000000783c38a0] [c0000000003f5f78] .pci_device_probe+0x148/0x150
> [c0000000783c3950] [c0000000004e1e8c] .driver_probe_device+0xdc/0x210
> [c0000000783c39f0] [c0000000004e20cc] .__driver_attach+0x10c/0x110
> [c0000000783c3a80] [c0000000004e1228] .bus_for_each_dev+0x98/0xf0
> [c0000000783c3b30] [c0000000004e1bf8] .driver_attach+0x28/0x40
> [c0000000783c3bb0] [c0000000004e07d8] .bus_add_driver+0x218/0x340
> [c0000000783c3c60] [c0000000004e2a2c] .driver_register+0x9c/0x1b0
> [c0000000783c3d00] [c0000000003f62d4] .__pci_register_driver+0x64/0x140
> [c0000000783c3da0] [c000000000b99f88] .ipr_init+0x4c/0x68
> [c0000000783c3e20] [c00000000000ad24] .do_one_initcall+0x1a4/0x1e0
> [c0000000783c3ee0] [c000000000b512d0] .kernel_init+0x14c/0x1fc
> [c0000000783c3f90] [c000000000022468] .kernel_thread+0x54/0x70
> Instruction dump:
> ebe1fff8 7c0803a6 4e800020 7c0802a6 fba1ffe8 fbe1fff8 7c7f1b78 f8010010
> f821ff71 e8030398 3120ffff 7c090110 <0b000000> e86303b0 482de065 60000000
> ---[ end trace 759bed76a85e8dec ]---
> scsi 0:0:1:0: Direct-Access     IBM-ESXS MAY2036RC        T106 PQ: 0 ANSI: 5
> ------------[ cut here ]------------
>
> I get lots more of these.  The obvious commit to point the finger at
> is 3308511c93e6 ("[SCSI] Make scsi_free_queue() kill pending SCSI
> commands") but the root cause may be something different.

Caused by

commit f7c9c6bb14f3104608a3a83cadea10a6943d2804
Author: Anton Blanchard <anton@samba.org>
Date:   Thu Nov 3 08:56:22 2011 +1100

    [SCSI] Fix block queue and elevator memory leak in scsi_alloc_sdev

Doesn't completely do the teardown.  The true fix is to do a proper
teardown instead of hand rolling it

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
hpsa: Disable ASPM

commit e5a44df85e8d78e5c2d3d2e4f59b460905691e2f upstream.

The Windows driver .inf disables ASPM on hpsa devices. Do the same because the
selection of a non default ASPM policy can cause the device to hang.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Mike Miller <mike.miller@hp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
aacraid: controller hangs if kernel uses non-default ASPM policy

commit cf16123c9c8e346ed1dd171295a678d77648d7f8 upstream.

Aacraid controller can hang on some nodes if kernel uses non-default
(powersave) ASPM policy.  Controller hangs shortly after successful load and
hardware detection. Scsi error handler detects this hang and tries to restart
hardware but it does not help.

Initially it was noticed on RHEL6-based openVZ kernel after backporting
aacraid driver from mainline (RHEL6 kernel with original driver works well)
http://bugzilla.openvz.org/show_bug.cgi?id=2043

This issue happens because default ASPM policy was changed in Red Hat
kernels. Therefore guys from Red Hat have noticed this problem long time ago:
on Fedora 12
 https://bugzilla.redhat.com/show_bug.cgi?id=540478
on Fedora 14
 https://bugzilla.redhat.com/show_bug.cgi?id=679385

In RHEL6 kernel this issue was fixed, ASPM was disabled in aacraid driver. In
kernel changelog I've found that seems it was done by Matthew Garrett: -
[scsi] aacraid: Disable ASPM by default (Matthew Garrett) [599735]

However seems this patch was not submitted to mainline. I've reproduced this
issue on vanilla 3.1.0 kernel booted with "pcie_aspm.policy=powersave" option,
So I believe it makes sense to do it now.

Signed-off-by:	Vasily Averin <vvs@sw.ru>
[mjg: Checking the Windows drivers indicates that they disable ASPM under all
circumstances, so:]
Acked-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Achim Leubner <Achim_Leubner@pmc-sierra.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
saa7164: Add support for another HVR2200 hardware revision

commit 62dd28d0c659db29bdb89cfe9f0aefe42f0adfe9 upstream.

Hauppauge have released a new model rev, sub id 8940, this adds
support.

[stoth@kernellabs.com: I modified Tony's patch slightly in relation to the
 card numbering in saa7164.h, appending rather than inserting the new card
 - normal practise]
Signed-off-by: Tony Jago <tony@hammertelecom.com.au>
Signed-off-by: Steven Toth <stoth@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drm/i915/pch: Save/restore PCH_PORT_HOTPLUG across suspend

commit cda2bb78c24de7674eafa3210314dc75bed344a6 upstream.

At least on a Lenovo X220 the HPD bits of this are enabled at boot but
cleared after resume, which means plug interrupts stop working.

This also happens to fix DP displays re-lighting on resume.  I'm quite
certain that's an accident: the first DP link train inevitably fails on
that machine, and it's only serendipity that we're getting multiple plug
interrupts and the second train works.  But I shall take my victories
where I get them.

Signed-off-by: Adam Jackson <ajax@redhat.com>
Tested-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Cc: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
ARM: 7150/1: Allow kernel unaligned accesses on ARMv6+ processors

commit 8428e84d42179c2a00f5f6450866e70d802d1d05 upstream.

Recent gcc versions generate unaligned accesses by default on ARMv6 and
later processors. This patch ensures that the SCTLR.A bit is always
cleared on such processors to avoid kernel traping before
alignment_init() is called.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: John Linn <John.Linn@xilinx.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Net, libertas: Resolve memory leak in if_spi_host_to_card()

commit fe09b32a4361bea44169b2063e8c867cabb6a8ba upstream.

If we hit the default case in the switch in if_spi_host_to_card() we'll leak
the memory we allocated for 'packet'. This patch resolves the leak by freeing
the allocated memory in that case.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
rt2x00: Fix sleep-while-atomic bug in powersaving code.

commit ed66ba472a742cd8df37d7072804b2111cdb1014 upstream.

The generic powersaving code that determines after reception of a frame
whether the device should go back to sleep or whether is could stay
awake was calling rt2x00lib_config directly from RX tasklet context.
On a number of the devices this call can actually sleep, due to having
to confirm that the sleeping commands have been executed successfully.

Fix this by moving the call to rt2x00lib_config to a workqueue call.

This fixes bug https://bugzilla.redhat.com/show_bug.cgi?id=731672

Tested-by: Tomas Trnka <tomastrnka@gmx.com>
Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
mac80211: fix NULL dereference in radiotap code

commit f8d1ccf15568268c76f913b45ecdd33134387f1a upstream.

When receiving failed PLCP frames is enabled, there
won't be a rate pointer when we add the radiotap
header and thus the kernel will crash. Fix this by
not assuming the rate pointer is always valid. It's
still always valid for frames that have good PLCP
though, and that is checked & enforced.

This was broken by my
commit fc88518916793af8ad6a02e05ff254d95c36d875
Author: Johannes Berg <johannes.berg@intel.com>
Date:   Fri Jul 30 13:23:12 2010 +0200

    mac80211: don't check rates on PLCP error frames

where I removed the check in this case but didn't
take into account that the rate info would be used.

Reported-by: Xiaokang Qin <xiaokang.qin@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
mac80211: fix bug in ieee80211_build_probe_req

commit 5b2bbf75a24d6b06afff6de0eb4819413fd81971 upstream.

ieee80211_probereq_get() can return NULL in
which case we should clean up & return NULL
in ieee80211_build_probe_req() as well.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
nl80211: fix HT capability attribute validation

commit 6c7394197af90f6a332180e33f5d025d3037d883 upstream.

Since the NL80211_ATTR_HT_CAPABILITY attribute is
used as a struct, it needs a minimum, not maximum
length. Enforce that properly. Not doing so could
potentially lead to reading after the buffer.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
cfg80211: fix bug on regulatory core exit on access to last_request

commit 58ebacc66bd11be2327edcefc79de94bd6f5bb4a upstream.

Commit 4d9d88d1 by Scott James Remnant <keybuk@google.com> added
the .uevent() callback for the regulatory device used during
the platform device registration. The change was done to account
for queuing up udev change requests through udevadm triggers.
The change also meant that upon regulatory core exit we will now
send a uevent() but the uevent() callback, reg_device_uevent(),
also accessed last_request. Right before commiting device suicide
we free'd last_request but never set it to NULL so
platform_device_unregister() would lead to bogus kernel paging
request. Fix this and also simply supress uevents right before
we commit suicide as they are pointless.

This fix is required for kernels >= v2.6.39

$ git describe --contains 4d9d88d1
v2.6.39-rc1~468^2~25^2^2~21

The impact of not having this present is that a bogus paging
access may occur (only read) upon cfg80211 unload time. You
may also get this BUG complaint below. Although Johannes
could not reproduce the issue this fix is theoretically correct.

mac80211_hwsim: unregister radios
mac80211_hwsim: closing netlink
BUG: unable to handle kernel paging request at ffff88001a06b5ab
IP: [<ffffffffa030df9a>] reg_device_uevent+0x1a/0x50 [cfg80211]
PGD 1836063 PUD 183a063 PMD 1ffcb067 PTE 1a06b160
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
CPU 0
Modules linked in: cfg80211(-) [last unloaded: mac80211]

Pid: 2279, comm: rmmod Tainted: G        W   3.1.0-wl+ #663 Bochs Bochs
RIP: 0010:[<ffffffffa030df9a>]  [<ffffffffa030df9a>] reg_device_uevent+0x1a/0x50 [cfg80211]
RSP: 0000:ffff88001c5f9d58  EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88001d2eda88 RCX: ffff88001c7468fc
RDX: ffff88001a06b5a0 RSI: ffff88001c7467b0 RDI: ffff88001c7467b0
RBP: ffff88001c5f9d58 R08: 000000000000ffff R09: 000000000000ffff
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88001c7467b0
R13: ffff88001d2eda78 R14: ffffffff8164a840 R15: 0000000000000001
FS:  00007f8a91d8a6e0(0000) GS:ffff88001fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff88001a06b5ab CR3: 000000001c62e000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process rmmod (pid: 2279, threadinfo ffff88001c5f8000, task ffff88000023c780)
Stack:
 ffff88001c5f9d98 ffffffff812ff7e5 ffffffff8176ab3d ffff88001c7468c2
 000000000000ffff ffff88001d2eda88 ffff88001c7467b0 ffff880000114820
 ffff88001c5f9e38 ffffffff81241dc7 ffff88001c5f9db8 ffffffff81040189
Call Trace:
 [<ffffffff812ff7e5>] dev_uevent+0xc5/0x170
 [<ffffffff81241dc7>] kobject_uevent_env+0x1f7/0x490
 [<ffffffff81040189>] ? sub_preempt_count+0x29/0x60
 [<ffffffff814cab1a>] ? _raw_spin_unlock_irqrestore+0x4a/0x90
 [<ffffffff81305307>] ? devres_release_all+0x27/0x60
 [<ffffffff8124206b>] kobject_uevent+0xb/0x10
 [<ffffffff812fee27>] device_del+0x157/0x1b0
 [<ffffffff8130377d>] platform_device_del+0x1d/0x90
 [<ffffffff81303b76>] platform_device_unregister+0x16/0x30
 [<ffffffffa030fffd>] regulatory_exit+0x5d/0x180 [cfg80211]
 [<ffffffffa032bec3>] cfg80211_exit+0x2b/0x45 [cfg80211]
 [<ffffffff8109a84c>] sys_delete_module+0x16c/0x220
 [<ffffffff8108a23e>] ? trace_hardirqs_on_caller+0x7e/0x120
 [<ffffffff814cba02>] system_call_fastpath+0x16/0x1b
Code: <all your base are belong to me>
RIP  [<ffffffffa030df9a>] reg_device_uevent+0x1a/0x50 [cfg80211]
 RSP <ffff88001c5f9d58>
CR2: ffff88001a06b5ab
---[ end trace 147c5099a411e8c0 ]---

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Scott James Remnant <keybuk@google.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
ip6_tunnel: copy parms.name after register_netdevice

commit 731abb9cb27aef6013ce60808a04e04a545f3f4e upstream.

Commit 1c5cae815d removed an explicit call to dev_alloc_name in ip6_tnl_create
because register_netdevice will now create a valid name.  This works for the
net_device itself.

However the tunnel keeps a copy of the name in the parms structure for the
ip6_tnl associated with the tunnel.  parms.name is set by copying the net_device
name in ip6_tnl_dev_init_gen.  That function is called from ip6_tnl_dev_init in
ip6_tnl_create, but it is done before register_netdevice is called so the name
is set to a bogus value in the parms.name structure.

This shows up if you do a simple tunnel add, followed by a tunnel show:

[root@localhost ~]# ip -6 tunnel add remote fec0::100 local fec0::200
[root@localhost ~]# ip -6 tunnel show
ip6tnl0: ipv6/ipv6 remote :: local :: encaplimit 0 hoplimit 0 tclass 0x00 flowlabel 0x00000 (flowinfo 0x00000000)
ip6tnl%d: ipv6/ipv6 remote fec0::100 local fec0::200 encaplimit 4 hoplimit 64 tclass 0x00 flowlabel 0x00000 (flowinfo 0x00000000)
[root@localhost ~]#

Fix this by moving the strcpy out of ip6_tnl_dev_init_gen, and calling it after
register_netdevice has successfully returned.

Signed-off-by: Josh Boyer <jwboyer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
PM / driver core: disable device's runtime PM during shutdown

commit af8db1508f2c9f3b6e633e2d2d906c6557c617f9 upstream.

There may be an issue when the user issue "reboot/shutdown" command, then
the device has shut down its hardware, after that, this runtime-pm featured
device's driver will probably be scheduled to do its suspend routine,
and at its suspend routine, it may access hardware, but the device has
already shutdown physically, then the system hang may be occurred.

I ran out this issue using an auto-suspend supported USB devices, like
3G modem, keyboard. The usb runtime suspend routine may be scheduled
after the usb controller has been shut down, and the usb runtime suspend
routine will try to suspend its roothub(controller), it will access
register, then the system hang occurs as the controller is shutdown.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Acked-by: Ming Lei <tom.leiming@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
pch_phub: Support new device LAPIS Semiconductor ML7831 IOH

commit 584ad00ce4bfe594e4c4a89944b3c635187a1ca1 upstream.

ML7831 is companion chip for Intel Atom E6xx series.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
pch_phub: Fix MAC address writing issue for LAPIS ML7831

commit 2a9887919457c6e1bd482e8448223be59d19010a upstream.

ISSUE:
Using ML7831, MAC address writing doesn't work well.

CAUSE:
ML7831 and EG20T have the same register map for MAC address access.
However, this driver processes the writing the same as ML7223.
This is not true.
This driver must process the writing the same as EG20T.
This patch fixes the issue.

Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Cc: Masayuki Ohtak <masa-korg@dsn.okisemi.com>
Cc: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Denis Turischev <denis@compulab.co.il>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
pch_uart: Fix hw-flow control issue

commit a1d7cfe29f13cf45f8094929864b9c66bf0cd91b upstream.

Using hardware flow control,
currently, register of the control-bit(AFE) is not set.
This patch fixes the issue.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
pch_uart: Fix DMA resource leak issue

commit 90f04c2926cfb5bf74533b0a7766bc896f6a0c0e upstream.

Changing UART mode PIO->DMA->PIO->DMA like below, pch_uart driver can't get
DMA channel resource.

setserial /dev/ttyPCH0 ^low_latency
setserial /dev/ttyPCH0 low_latency

CAUSE:
Changing mode using setserial command, ".startup" function which gets DMA
channel is called before ".verify_port" function which sets
dma-flag(use_dma/use_dma_flag) as 1.

PIO->DMA
  .startup: Since dma-flag is 0, DMA channel is not requested.
  .verify_port: dma-flag is set as 1.
  .shutdown: N/A

DMA->PIO
  .startup: Since dma-flag is 1, DMA channel is requested.
  .verify_port: dma-flag is set as 0.
  .shutdown: Since dma-flag is 0, DMA channel is not released.

This means DMA channel resource leak occurs.
Next time, this driver can't get DMA channel resource forever.

MODIFICATION:
  Currently, when release DMA channel resource, this driver checks dma-flag.
  However, this specification occurs the above issue.
  This driver must check whether dma_request_channel is executed or not.
  The values are saved in private data variable "chan_tx/chan_tx".
  These variables mean if the value is NULL, DMA channel is not requested,
  if not NULL, DMA channel is requested.

This patch fixes the issue.

Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
pch_uart: Support new device LAPIS Semiconductor ML7831 IOH

commit 8249f743f732ccbc3056428945ab1d9bd36d46bf upstream.

ML7831 is companion chip for Intel Atom E6xx series.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>