Follow altera_jtag_uart.  This fixes a crash if there is a mistake in the DTS.

Signed-off-by: Yuriy Kozlov <ykozlov@ptcusa.com>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The patch does the following

- The pm_runtime_disable is called in the remove not in the error
  case of probe.The patch calls the pm_runtime_disable in the error
  case.
- Calls pm_runtime_put in the error case.
- The  up is not freed in the error path. Fix the memory leak by using
  devm_* so that the memory need not be freed in the driver.
- Also the iounmap is not called fix the same by calling using devm_ioremap.
- Make the name of the error tags more meaningful.

Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Govindraj.R <govindraj.raja@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit 360f748b204275229f8398cb2f9f53955db1503b
"serial: PL011: clear pending interrupts"
attempts to clear interrupts by writing to a
yet-unassigned memory address. This fixes the issue.

The breaking patch is marked for stable so should be
carried along with the other patch.

Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: stable <stable@vger.kernel.org>
Cc: Nicolas Pitre <nico@fluxnic.net>
Reported-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Usage of /etc/modprobe.conf file was deprecated by module-init-tools and
is no longer parsed by new kmod tool. References to this file are
replaced in Documentation, comments and Kconfig according to the
context.

There are also some references to the old /etc/modules.conf from 2.4
kernels that are being removed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`

Signed-off-by: David Howells <dhowells@redhat.com>

Disintegrate asm/system.h for Sparc.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: sparclinux@vger.kernel.org

Disintegrate asm/system.h for CRIS.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
cc: linux-cris-kernel@axis.com

Disintegrate asm/system.h for ARM.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Russell King <linux@arm.linux.org.uk>
cc: linux-arm-kernel@lists.infradead.org

When DMA is enabled, sh-sci transfer begins with
 uart_start()
  sci_start_tx()
    if (cookie_tx < 0) schedule_work()
Then, starts DMA when wq scheduled, -- (A)
 process_one_work()
  work_fn_rx()
   cookie_tx = desc->submit_tx()
And finishes when DMA transfer ends, -- (B)
 sci_dma_tx_complete()
  async_tx_ack()
  cookie_tx = -EINVAL
  (possible another schedule_work())

This A to B sequence is not reentrant, since controlling variables
(for example, cookie_tx above) are not queues nor lists. So, they
must be invoked as A B A B..., otherwise results in kernel crash.

To ensure the sequence, sci_start_tx() seems to test if cookie_tx < 0
(represents "not used") to call schedule_work().
But cookie_tx will not be set (to a cookie, also means "used") until
in the middle of work queue scheduled function work_fn_tx().

This gap between the test and set allows the breakage of the sequence
under the very frequently call of uart_start().
Another gap between async_tx_ack() and another schedule_work() results
in the same issue, too.

This patch introduces a new condition "cookie_tx == 0" just to mark
it is "busy" and assign it within spin-locked region to fill the gaps.

Signed-off-by: Takashi Yoshii <takashi.yoshii.zj@renesas.com>
Reviewed-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

This makes vio_register_driver() get the module owner & name at compile
time like PCI drivers do, and adds a name pointer directly in struct
vio_driver to avoid having to explicitly initialize the embedded
struct device.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: David S. Miller <davem@davemloft.net>

In preparation to convert SA1100 to sparse irq, set .nr_irqs for each machine
and explicitly include mach/irqs.h as needed.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The oom killer chooses not to kill a thread if:

 - an eligible thread has already been oom killed and has yet to exit,
   and

 - an eligible thread is exiting but has yet to free all its memory and
   is not the thread attempting to currently allocate memory.

SysRq+F manually invokes the global oom killer to kill a memory-hogging
task.  This is normally done as a last resort to free memory when no
progress is being made or to test the oom killer itself.

For both uses, we always want to kill a thread and never defer.  This
patch causes SysRq+F to always kill an eligible thread and can be used to
force a kill even if another oom killed thread has failed to exit.

Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add inline wrappers for device_prep_slave_sg() and device_prep_dma_cyclic()
interfaces to hide new parameter from current users of affected interfaces.
Convert current users to use new wrappers instead of direct calls.
Suggested by Russell King [https://lkml.org/lkml/2012/2/3/269

].

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>

so remove the code that tests for it.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Also while at it, add some help text indicating why you shouldn't
enable that driver under normal circumstances

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This patch adds clk_prepare/clk_unprepare calls to the serial/pxa
driver by using the helper functions clk_prepare_enable and
clk_disable_unprepare.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Cc: Haojian Zhuang <haojian.zhuang@marvell.com>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Bugzilla 40012: PIO_UNIMAP bug: error updating Unicode-to-font map
https://bugzilla.kernel.org/show_bug.cgi?id=40012



The unicode font map for the virtual console is a 32x32x64 table which
allocates rows dynamically as entries are added.  The unicode value
increases sequentially and should count all entries even in empty
rows.  The defect is when copying the unicode font map in con_set_unimap(),
the unicode value is not incremented properly.  The wrong unicode value
is entered in the new font map.

Signed-off-by: Liz Clark <liz.clark@hp.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Chanho Min reported that when the boot loader transfers
control to the kernel, there may be pending interrupts
causing the UART to lock up in an eternal loop trying to
pick tokens from the FIFO (since the RX interrupt flag
indicates there are tokens) while in practice there are
no tokens - in fact there is only a pending IRQ flag.

This patch address the issue with a combination of two
patches suggested by Russell King that clears and mask
all interrupts at probe() and clears any pending error
and RX interrupts at port startup time.

We suspect the spurious interrupts are a side-effect of
switching the UART from FIFO to non-FIFO mode.

Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Reported-by: Chanho Min <chanho0207@gmail.com>
Suggested-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Jong-Sung Kim <neidhard.kim@lge.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Introduce a new config option HVC_XEN_FRONTEND to enable/disable the
xenbus based pv console frontend.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This patch implements support for multiple consoles:
consoles other than the first one are setup using the traditional xenbus
and grant-table based mechanism.
We use a list to keep track of the allocated consoles, we don't
expect too many of them anyway.

Changes in v3:

- call hvc_remove before removing the console from xenconsoles;
- do not lock xencons_lock twice in the destruction path;
- use the DEFINE_XENBUS_DRIVER macro.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

When kernel reboot, tty circular buffer is reset before last TX DMA interrupt is called,
while the buffer tail is updated in TX DMA interrupt handler. So, don't update the buffer
tail if it is reset.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

We forgot to set the "key_map" variable here, so it's still NULL.  This
was introduced recently in 079c9534 "vt:tackle kbd_table".

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Fixes:

WARNING: drivers/tty/serial/built-in.o(.data+0x30): Section mismatch in reference from the variable vt8500_platform_driver to the function .init.text:vt8500_serial_probe()
The variable vt8500_platform_driver references
the function __init vt8500_serial_probe()

And mark the remove pointer while we are here.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The two callers to serial_out_sync() have a struct port right
there in scope, but then pass in a struct 8250_port which then
is locally resolved back to a struct port.

Delete the needless back and forth and just pass in the struct
port directly.  Rename the function to have "_port" in its
name, so the name <--> args relationship is consistent with the
other serial_in/out vs serial_port_in/out function classes.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The serial_in and serial_out helpers are expecting to operate
on an 8250_port struct.  These in turn go after the contained
normal port struct which actually has the actual in/out accessors.

But what is happening in some cases, is that a function is passed
in a port struct, and it runs container_of to get the 8250_port
struct, and then it uses serial_in/out helpers on that.  But when
you do, it goes full circle, since it jumps back inside the 8250_port
to find the contained port struct (which we already knew!).

So, if we are operating in a scope where we know the struct port,
then use the serial_port_in/out helpers and avoid the bouncing
around.  If we don't have the struct port handy, and it isn't
worth making a local for it, then just leave things as-is which
uses the serial_in/out helpers that will resolve the 8250_port
onto the struct port.

Mostly, gcc figures this out on its own -- so this doesn't bring to
the table any revolutionary runtime delta.  However, it is somewhat
misleading to always hammer away on 8250 structs, when the actual
underlying property isn't at all 8250 specific -- and this change
makes that clear.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The serial_8250_port struct contains within a serial_port struct
and many times one or the other, or both are in scope within
functions via a passed in arg, or via container_of.

However there are a lot of cases where we have access directly
to the port pointer, but yet go through the parent 8250_port
structure instead to get it.  These should just use the port
struct directly.

Similarly there are cases where it makes sense (from a code
cleanliness point of view) to declare a local for the port
struct, so we aren't going through the parent 8250_port struct
repeatedly to get to it.

We get a small reduction in text size, but it appears that
gcc was smart enough to internally be doing most of this
already, so the readability improvement is the larger gain.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

These might have worked some magic with an ancient gcc back in
1992, but "objdump --disassemble" on gcc 4.6 on x86-64 shows
identical output before and after this commit.  Send the casts
and their hysterical rasins to the bitbucket.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Currently 8250.c has serial_in and serial_out as shortcuts
to doing the port I/O.  They are implemented as macros a
ways down in the file.  This isn't by accident, but is
implicitly required, so cpp doesn't mangle other instances
of the common string "serial_in", as it exists as a field
in the port struct itself.

The above mangling avoidance violates the principle of least
surprise, and it also prevents the shortcuts from being
relocated up to the top of file, or into 8250.h -- either
being a better location than the current one.

Move them to 8250.h so other 8250-like drivers can also use
the shortcuts, and in the process, make the conflicting
names go away by using static inlines instead of macros.
The object file size remains unchanged with this modification.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This is the last traces of pausing I/O that we had back some
twenty years ago.  Probably was only required for 8MHz ISA
cards running "on the edge" at 12MHz.  Anyway it hasn't been
in use for years, so lets just bury it for good.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Document default_baud and user_uartclk module parameters.

Signed-off-by: Darren Hart <dvhart@linux.intel.com>
CC: Tomoya MORINAGA <tomoya.rohm@gmail.com>
CC: Feng Tang <feng.tang@intel.com>
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Rather than hardcode 9600, use the existing default_baud parameter (which
also defaults to 9600).

Signed-off-by: Darren Hart <dvhart@linux.intel.com>
CC: Tomoya MORINAGA <tomoya.rohm@gmail.com>
CC: Feng Tang <feng.tang@intel.com>
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

For cases where boards with non-default clocks are not yet added to the kernel
or when the clock varies across hardware revisions, it is useful to be
able to specify the UART clock on the kernel command line.

Add the user_uartclk parameter and prefer it, if set, to the default and
board specific UART clock settings. Specify user_uartclock on the command-line
with "pch_uart.user_uartclk=48000000".

Signed-off-by: Darren Hart <dvhart@linux.intel.com>
CC: Tomoya MORINAGA <tomoya.rohm@gmail.com>
CC: Feng Tang <feng.tang@intel.com>
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Add support for the Fish River Island II (FRI2) UART clock following the CM-iTC
quirk handling mechanism. Depending on the firmware installed on the device, the
FRI2 uses a 48MHz or a 64MHz UART clock. This is detected with DMI strings.

Add similar UART clock quirk handling to the pch_console_setup() function to
enable kernel messages on boards with non-standard UART clocks.

Per Alan's suggestion, abstract out UART clock selection into
pch_uart_get_uartclk() to avoid code duplication.

Signed-off-by: Darren Hart <dvhart@linux.intel.com>
CC: Tomoya MORINAGA <tomoya.rohm@gmail.com>
CC: Feng Tang <feng.tang@intel.com>
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The term "base baud" refers to the fastest baud rate the device can communicate
at. This is clock/16. pch_uart is using base_baud as the clock itself. Rename
the variables to be semantically correct.

Signed-off-by: Darren Hart <dvhart@linux.intel.com>
CC: Tomoya MORINAGA <tomoya.rohm@gmail.com>
CC: Feng Tang <feng.tang@intel.com>
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The runtime PM of sh-sci devices is enabled when sci_probe() returns,
so the pm_runtime_put_sync() executed by driver_probe_device()
attempts to suspend the device.  Then, in some situations, a
diagnostic message is printed to the console by one of the runtime
suspend routines handling the sh-sci device, which causes synchronous
runtime resume to be started from the device's own runtime suspend
callback.  This causes rpm_resume() to be run eventually, which sees
the RPM_SUSPENDING status set by rpm_suspend() and waits for it to
change.  However, the device's runtime PM status cannot change at
that point, because the routine that has set it waits for the
rpm_suspend() to return.  A deadlock occurs as a result.

To avoid that make sci_init_single() increment the device's
runtime PM usage counter, so that it cannot be suspended by
driver_probe_device().  That counter has to be decremented
eventually, so make sci_startup() do that before starting to
actually use the device and make sci_shutdown() increment it
again before returning to balance the incrementation carried out by
sci_startup().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

The PowerPC legacy iSeries platform is being removed so this is no
longer selectable.

Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The PowerPC legacy iSeries platform is being removed, so this code is no
longer needed.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

In addition to the /32 prescaler, the MPC5200B supports a second
baudrate prescaler /4 to reach higher baudrates.

The current calculation (introduced with commit 0d1f22e4) in the kernel
preferes this low prescaler as often as possible, but with some
imprecise counterparts the communication on low baudrates fails.

According a support-mail from freescale the low prescaler (/4) allows
just 1% tolerance in bittiming in contrast to 4% of the high prescaler
(/32).  The prescaler not only affects the baudrate-calculation, but
also the sampling of the bits on the wire.

With this patch, we use the slightly less precise, but higher tolerant
prescaler calculation on low baudrates up to (and including) 115200 baud
and the more precise calculation above.

Tested on a custom MPC5200B board with "fsl,mpc5200b-psc-uart".

Calculation Examples with prescaler (PS) 4 and 32 and divisor (DIV) on
various baudrates. Real stands for the real baudrate generated and Diff
for the differences between:
     50 Baud PS 32 DIV 0xa122 Real      50 Diff   0.00%
     75 Baud PS 32 DIV 0x6b6c Real      75 Diff   0.00%
    110 Baud PS 32 DIV 0x493e Real     110 Diff   0.00%
    134 Baud PS 32 DIV 0x3c20 Real     133 Diff   0.75%
    150 Baud PS 32 DIV 0x35b6 Real     150 Diff   0.00%
    200 Baud PS 32 DIV 0x2849 Real     199 Diff   0.50%
    300 Baud PS  4 DIV 0xd6d8 Real     300 Diff   0.00%
             PS 32 DIV 0x1adb Real     300 Diff   0.00%
    600 Baud PS  4 DIV 0x6b6c Real     600 Diff   0.00%
             PS 32 DIV 0x0d6e Real     599 Diff   0.17%
   1200 Baud PS  4 DIV 0x35b6 Real    1200 Diff   0.00%
             PS 32 DIV 0x06b7 Real    1199 Diff   0.08%
   1800 Baud PS  4 DIV 0x23cf Real    1799 Diff   0.06%
             PS 32 DIV 0x047a Real    1799 Diff   0.06%
   2400 Baud PS  4 DIV 0x1adb Real    2400 Diff   0.00%
             PS 32 DIV 0x035b Real    2401 Diff - 0.04%
   4800 Baud PS  4 DIV 0x0d6e Real    4799 Diff   0.02%
             PS 32 DIV 0x01ae Real    4796 Diff   0.08%
   9600 Baud PS  4 DIV 0x06b7 Real    9598 Diff   0.02%
             PS 32 DIV 0x00d7 Real    9593 Diff   0.07%
  19200 Baud PS  4 DIV 0x035b Real   19208 Diff - 0.04%
             PS 32 DIV 0x006b Real   19275 Diff - 0.39%
  38400 Baud PS  4 DIV 0x01ae Real   38372 Diff   0.07%
             PS 32 DIV 0x0036 Real   38194 Diff   0.54%
  57600 Baud PS  4 DIV 0x011e Real   57692 Diff - 0.16%
             PS 32 DIV 0x0024 Real   57291 Diff   0.54%
  76800 Baud PS  4 DIV 0x00d7 Real   76744 Diff   0.07%
             PS 32 DIV 0x001b Real   76388 Diff   0.54%
 115200 Baud PS  4 DIV 0x008f Real  115384 Diff - 0.16%
             PS 32 DIV 0x0012 Real  114583 Diff   0.54%
 153600 Baud PS  4 DIV 0x006b Real  154205 Diff - 0.39%
             PS 32 DIV 0x000d Real  158653 Diff - 3.29%
 230400 Baud PS  4 DIV 0x0048 Real  229166 Diff   0.54%
             PS 32 DIV 0x0009 Real  229166 Diff   0.54%
 307200 Baud PS  4 DIV 0x0036 Real  305555 Diff   0.54%
             PS 32 DIV 0x0007 Real  294642 Diff   4.09%
 460800 Baud PS  4 DIV 0x0024 Real  458333 Diff   0.54%
             PS 32 DIV 0x0005 Real  412500 Diff  10.48%
 500000 Baud PS  4 DIV 0x0021 Real  500000 Diff   0.00%
             PS 32 DIV 0x0004 Real  515625 Diff - 3.13%
 576000 Baud PS  4 DIV 0x001d Real  568965 Diff   1.22%
             PS 32 DIV 0x0004 Real  515625 Diff  10.48%
 614400 Baud PS  4 DIV 0x001b Real  611111 Diff   0.54%
             PS 32 DIV 0x0003 Real  687500 Diff -11.90%
 921600 Baud PS  4 DIV 0x0012 Real  916666 Diff   0.54%
             PS 32 DIV 0x0002 Real 1031250 Diff -11.90%
1000000 Baud PS  4 DIV 0x0011 Real  970588 Diff   2.94%
             PS 32 DIV 0x0002 Real 1031250 Diff - 3.13%
1152000 Baud PS  4 DIV 0x000e Real 1178571 Diff - 2.31%
             PS 32 DIV 0x0002 Real 1031250 Diff  10.48%
1500000 Baud PS  4 DIV 0x000b Real 1500000 Diff   0.00%
             PS 32 DIV 0x0001 Real 2062500 Diff -37.50%
2000000 Baud PS  4 DIV 0x0008 Real 2062500 Diff - 3.13%
             PS 32 DIV 0x0001 Real 2062500 Diff - 3.13%
2500000 Baud PS  4 DIV 0x0007 Real 2357142 Diff   5.71%
             PS 32 DIV 0x0001 Real 2062500 Diff  17.50%
3000000 Baud PS  4 DIV 0x0006 Real 2750000 Diff   8.33%
             PS 32 DIV 0x0001 Real 2062500 Diff  31.25%
3500000 Baud PS  4 DIV 0x0005 Real 3300000 Diff   5.71%
             PS 32 DIV 0x0001 Real 2062500 Diff  41.07%
4000000 Baud PS  4 DIV 0x0004 Real 4125000 Diff - 3.13%
             PS 32 DIV 0x0001 Real 2062500 Diff  48.44%

Signed-off-by: Frank Benkert <frank.benkert@avat.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This is supposed to be doing a shift before the comparison instead of
just doing a bitwise AND directly.  The current code means the start()
just returns without doing anything.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>