This patch fixes many bugs in the code dealing with the hardware handshake.

As an example, in atmel_set_termios(), we used to test whether the CRTSCTS
c_cflag was set. If so, we selected the "Hardware Handshake" mode through the
Mode Register. However, few lines below the mode was reset to "Normal" (0).
So there was no way to select the "Hardware Handshake" mode. To fix this issue,
we moved the CRTSCRTS c_cflag test AFTER the mode has been reset to "Normal".

Also setting the RTSEN and RTSDIS bits in the Control Register has different
results whether the USART is set in "Normal" or "Hardware Handshake" mode:

1) "Normal" mode
- the RTSEN bit forces the RTS line to low level, which tells the remote peer
  that we are ready to received new data.
- the RTSDIS bit forces the RTS line to high level, which tells the remote peer
  to stop sending new data.

2) "Hardware Handshake" mode
- the RTSEN bit forces the RTS line to high level.
- the RTSDIS bit lets the hardware control the RTS line.

WARNING:
when FIFOs are not available or not enabled, the RTS line is controlled by the
PDC. This is why using the Hardware Handshake mode requires using the PDC
channel for reception. However the Hardware Handshake mode DOES NOT work with
DMA controller since it cannot control the RTS line.
Future designs with FIFOs will introduce a new feature: the RTS line will be
controlled by the RX FIFO using thresholds. This patch was tested with this new
design.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

-EDEFER error wasn't handle properly by atmel_serial_probe().
As an example, when atmel_serial_probe() is called for the first time, we pass
the test_and_set_bit() test to check whether the port has already been
initalized. Then we call atmel_init_port(), which may return -EDEFER, possibly
returned before by clk_get(). Consequently atmel_serial_probe() used to return
this error code WITHOUT clearing the port bit in the "atmel_ports_in_use" mask.
When atmel_serial_probe() was called for the second time, it used to fail on
the test_and_set_bit() function then returning -EBUSY.

When atmel_serial_probe() fails, this patch make it clear the port bit in the
"atmel_ports_in_use" mask, if needed, before returning the error code.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: <stable@vger.kernel.org> # 3.12+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

atmel_serial_probe() calls atmel_init_port(). In turn, atmel_init_port() calls
clk_disable_unprepare() to disable the peripheral clock before returning.

Later atmel_serial_probe() accesses some I/O registers such as the Mode and
Control registers for RS485 support then the Name and Version registers, through a call to
atmel_get_ip_name(), but at that moment the peripheral clock was still
disabled.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: <stable@vger.kernel.org> # 3.12+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dma_sync_*_for_cpu() and dma_sync_*_for_device() use 'enum dma_data_direction',
not 'enum dma_transfer_direction'

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

MARCO will not be supported any more and the project was dropped.
it has been replaced by CSR atlas7.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit 2aff5e2b ('tty: Change
tty lock order to master->slave') added a warning which is broken
and unnecessary now that the tty lock has fixed lock subclasses,
added in commit 2febdb63
('tty: Preset lock subclass for nested tty locks').

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Enable APM X-Gene SoC serial port functionality when using ACPI table to
initialize serial port.

Signed-off-by: Feng Kan <fkan@apm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

There is no need to terminate transfer in the __dma_rx_complete() since it's
called at the end of transfer. Special case when serial timeout occurs is
handled separately where we have to terminate transfer.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

By using devm_request_irq() we can have a shorter and cleaner code.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

By using devm_clk_get() we can have a shorter and cleaner code.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

By using devm_kzalloc() we can have a shorter and cleaner code.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Instead of jumping to the 'out' label, let's return the error immediately, which
makes the code shorter and cleaner.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Because the OMAP3 UART ignores MCR[1] (RTS) in autoRTS mode, autoRTS
mode must not be enabled unless RTS is set (or port->mctrl & TIOCM_RTS,
which is equivalent).

Fixes premature raising of RTS in omap_8250_set_termios() -- RTS was
raised even before UART mode was selected.
Fixes raise of RTS after port has been shutdown; omap_8250_pm() re-enabled
RTS after omap_8250_shutdown().

Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The OMAP3 UART ignores MCR[1] (ie., UART_MCR_RTS) when in autoRTS
mode (UPF_HARD_FLOW + CRTSCTS). This makes it impossible for either
the serial core or userspace to manually flow control the sender.

Disable autoRTS mode when RTS is lowered and restore the previous
mode when RTS is raised.

Note that the OMAP3 UART provides no mechanism for switching from
autoRTS mode without corrupting incoming data; to access the
necessary register, the line control settings must be set to 8-e-2
and thus any data received during that time will be interpreted with
those settings. This corruption has been observed in practice.

Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Trivial fixes for omap-serial.

Signed-off-by: Pavel Machek <pavel@ucw.cz>

index 18c30ca..f43ed2c 100644
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch invokes add_preferred_console() with ttyS based on ttyO
arguments if the user didn't specify it on its own. This ensures that
the user will see the kernel booting on his serial console in case he
forgot to update the command line.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The current output of the device probing looks like this:

ColdFire internal UART serial driver
(NULL device *): ttyS0 at MMIO 0xfc060000 (irq = 90, base_baud = 5208333) is a ColdFire UART
console [ttyS0] enabled
(NULL device *): ttyS1 at MMIO 0xfc064000 (irq = 91, base_baud = 5208333) is a ColdFire UART
(NULL device *): ttyS2 at MMIO 0xfc068000 (irq = 92, base_baud = 5208333) is a ColdFire UART

Fix the port device linkage at probing time so that the device name is
printed out properly, and not "(NULL device *)".

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Trivially fix the following compile time warnings:

  CC      drivers/tty/serial/mcf.o
drivers/tty/serial/mcf.c: In function ‘mcf_set_termios’:
drivers/tty/serial/mcf.c:201:19: warning: unused variable ‘pp’
drivers/tty/serial/mcf.c: In function ‘mcf_config_rs485’:
drivers/tty/serial/mcf.c:444:19: warning: unused variable ‘pp’

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Change my email contact address from the obsolete gerg@snapgear.com to
gerg@uclinux.org.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The 8250_omap serial driver is a new user of CONFIG_PM_RUNTIME.

However, after commit b2b49ccb (PM: Kconfig: Set PM_RUNTIME if
PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so
#ifdef blocks depending on CONFIG_PM_RUNTIME may now be changed to
depend on CONFIG_PM.

Replace CONFIG_PM_RUNTIME with CONFIG_PM in 8250_omap.c.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

After commit b2b49ccb (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so #ifdef blocks
depending on CONFIG_PM_RUNTIME may now be changed to depend on
CONFIG_PM.

Replace CONFIG_PM_RUNTIME with CONFIG_PM everywhere under
drivers/tty/.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Make the serial_mctrl_gpio driver the first user of the new gpiod_set_array
function, which is now available in the linux-gpio devel tree.
All modem control output signals are now set simultaneously.

Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Both uart_handle_dcd_change() and uart_handle_cts_change() require a
port lock to be held and will emit a warning when lockdep is enabled.
Held corresponding lock.

This fixes the following warnings:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at drivers/tty/serial/serial_core.c:2760 uart_handle_dcd_change+0xc8/0xf8()
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 3.18.0-rc5+ #26
[<c000dff8>] (unwind_backtrace) from [<c000bc70>] (show_stack+0x10/0x14)
[<c000bc70>] (show_stack) from [<c00192ac>] (warn_slowpath_common+0x6c/0x8c)
[<c00192ac>] (warn_slowpath_common) from [<c00192e8>] (warn_slowpath_null+0x1c/0x24)
[<c00192e8>] (warn_slowpath_null) from [<c0182984>] (uart_handle_dcd_change+0xc8/0xf8)
[<c0182984>] (uart_handle_dcd_change) from [<c018625c>] (serial_pxa_irq+0x268/0x3b0)
[<c018625c>] (serial_pxa_irq) from [<c004d0d4>] (handle_irq_event_percpu+0x50/0x16c)
[<c004d0d4>] (handle_irq_event_percpu) from [<c004d22c>] (handle_irq_event+0x3c/0x5c)
[<c004d22c>] (handle_irq_event) from [<c004f7d0>] (handle_level_irq+0x94/0x118)
[<c004f7d0>] (handle_level_irq) from [<c004ca0c>] (generic_handle_irq+0x20/0x30)
[<c004ca0c>] (generic_handle_irq) from [<c004cbe0>] (__handle_domain_irq+0x38/0x70)
[<c004cbe0>] (__handle_domain_irq) from [<c00085c4>] (ichp_handle_irq+0x24/0x34)
[<c00085c4>] (ichp_handle_irq) from [<c000c7e4>] (__irq_svc+0x44/0x54)
Exception stack(0xc07c7f58 to 0xc07c7fa0)
7f40:                                                       00000001 00000001
7f60: 00000000 20000013 c07c6000 00000000 00000000 c07ce0a4 c07d7798 00000000
7f80: c07e8fb8 0000004c 00000000 c07c7fa0 c0044798 c0009f20 20000013 ffffffff
[<c000c7e4>] (__irq_svc) from [<c0009f20>] (arch_cpu_idle+0x28/0x38)
[<c0009f20>] (arch_cpu_idle) from [<c003c974>] (cpu_startup_entry+0x1b8/0x220)
[<c003c974>] (cpu_startup_entry) from [<c0338c54>] (start_kernel+0x39c/0x40c)
---[ end trace 4c1b7ae03f6d9d30 ]---
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at drivers/tty/serial/serial_core.c:2791 uart_handle_cts_change+0xa0/0xdc()
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Tainted: G        W      3.18.0-rc5+ #26
[<c000dff8>] (unwind_backtrace) from [<c000bc70>] (show_stack+0x10/0x14)
[<c000bc70>] (show_stack) from [<c00192ac>] (warn_slowpath_common+0x6c/0x8c)
[<c00192ac>] (warn_slowpath_common) from [<c00192e8>] (warn_slowpath_null+0x1c/0x24)
[<c00192e8>] (warn_slowpath_null) from [<c018528c>] (uart_handle_cts_change+0xa0/0xdc)
[<c018528c>] (uart_handle_cts_change) from [<c018624c>] (serial_pxa_irq+0x258/0x3b0)
[<c018624c>] (serial_pxa_irq) from [<c004d0d4>] (handle_irq_event_percpu+0x50/0x16c)
[<c004d0d4>] (handle_irq_event_percpu) from [<c004d22c>] (handle_irq_event+0x3c/0x5c)
[<c004d22c>] (handle_irq_event) from [<c004f7d0>] (handle_level_irq+0x94/0x118)
[<c004f7d0>] (handle_level_irq) from [<c004ca0c>] (generic_handle_irq+0x20/0x30)
[<c004ca0c>] (generic_handle_irq) from [<c004cbe0>] (__handle_domain_irq+0x38/0x70)
[<c004cbe0>] (__handle_domain_irq) from [<c00085c4>] (ichp_handle_irq+0x24/0x34)
[<c00085c4>] (ichp_handle_irq) from [<c000c7e4>] (__irq_svc+0x44/0x54)
Exception stack(0xc07c7f58 to 0xc07c7fa0)
7f40:                                                       00000001 00000001
7f60: 00000000 20000013 c07c6000 00000000 00000000 c07ce0a4 c07d7798 00000000
7f80: c07e8fb8 0000004c 00000000 c07c7fa0 c0044798 c0009f20 20000013 ffffffff
[<c000c7e4>] (__irq_svc) from [<c0009f20>] (arch_cpu_idle+0x28/0x38)
[<c0009f20>] (arch_cpu_idle) from [<c003c974>] (cpu_startup_entry+0x1b8/0x220)
[<c003c974>] (cpu_startup_entry) from [<c0338c54>] (start_kernel+0x39c/0x40c)
---[ end trace 4c1b7ae03f6d9d31 ]---

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The tty_kref_put() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The functions put_device() and tty_kref_put() test whether their argument
is NULL and then return immediately.
Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit 19e2ad6a ("n_tty: Remove overflow
tests from receive_buf() path") moved the increment of read_head into
the arguments list of read_buf_addr(). Function calls represent a
sequence point in C. Therefore read_head is incremented before the
character c is placed in the buffer. Since the circular read buffer is
a lock-less design since commit 6d76bd26
("n_tty: Make N_TTY ldisc receive path lockless"), this creates a race
condition that leads to communication errors.

This patch modifies the code to increment read_head _after_ the data
is placed in the buffer and thus fixes the race for non-SMP machines.
To fix the problem for SMP machines, memory barriers must be added in
a separate patch.

Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds suspend/resume support for the of-serial driver
to provide power management support on devices attatched.

The handling may vary since not every of_serial device is
an 8250 port. Currently only 8250 port handling is added
in the suspend/resume function based on the type switch.

Signed-off-by: Jingchang Lu <jingchang.lu@freescale.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Joseph Lo <josephl@nvidia.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Florina Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 2dea53bf.

Turns out to be broken :(

Cc: Jingchang Lu <jingchang.lu@freescale.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 513e4385.

It's broken :(

Cc: Jingchang Lu <jingchang.lu@freescale.com>
Cc: Joseph Lo <josephl@nvidia.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Attempting to use SysRq via the 8250 serial port with spin lock
debugging on on a uniprocessor system results in the following splat:

 SysRq :
 BUG: spinlock trylock failure on UP on CPU#0, swapper/0
  lock: serial8250_ports+0x0/0x8c0, .magic: dead4ead, .owner: swapper/0, .owner_cpu: 0
 CPU: 0 PID: 0 Comm: swapper Not tainted 3.18.0-rc4+ #37
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
  ffffffff8245ba00 ffffffff81628b28 ffffffff812c8d27 ffffffff81628b48
  ffffffff8106812e ffffffff8245ba00 ffffffff814e22ed ffffffff81628b68
  ffffffff810681a6 0000000000000000 0000000000000000 ffffffff81628b88
 Call Trace:
  <IRQ>  [<ffffffff812c8d27>] dump_stack+0x19/0x1b
  [<ffffffff8106812e>] spin_dump+0x7e/0xd0
  [<ffffffff810681a6>] spin_bug+0x26/0x30
  [<ffffffff8106843c>] do_raw_spin_trylock+0x4c/0x60
  [<ffffffff812cdb1d>] _raw_spin_trylock+0x1d/0x60
  [<ffffffff812336d8>] serial8250_console_write+0x68/0x190
  [<ffffffff811eb0b0>] ? sprintf+0x40/0x50
  [<ffffffff8106ab5e>] call_console_drivers.constprop.11+0x9e/0xf0
  [<ffffffff8106b276>] console_unlock+0x3e6/0x490
  [<ffffffff8106b595>] vprintk_emit+0x275/0x530
  [<ffffffff812c869a>] printk+0x4d/0x4f
  [<ffffffff8121e612>] __handle_sysrq+0x62/0x1b0
  [<ffffffff8121e5b5>] ? __handle_sysrq+0x5/0x1b0
  [<ffffffff8121ebc6>] handle_sysrq+0x26/0x30
  [<ffffffff81233157>] serial8250_rx_chars+0x1d7/0x250
  [<ffffffff812338bb>] serial8250_handle_irq+0x7b/0x90
  [<ffffffff812338f3>] serial8250_default_handle_irq+0x23/0x30
  [<ffffffff812318b3>] serial8250_interrupt+0x63/0xe0
  [<ffffffff8106d80e>] handle_irq_event_percpu+0x4e/0x200
  [<ffffffff8106da01>] handle_irq_event+0x41/0x70
  [<ffffffff810701ee>] ? handle_edge_irq+0x1e/0x110
  [<ffffffff8107026e>] handle_edge_irq+0x9e/0x110
  [<ffffffff810041c2>] handle_irq+0x22/0x40
  [<ffffffff812d096e>] do_IRQ+0x4e/0xf0
  [<ffffffff812cf4ed>] common_interrupt+0x6d/0x6d
  <EOI>  [<ffffffff8100acbf>] ? default_idle+0x1f/0xd0
  [<ffffffff8100acbd>] ? default_idle+0x1d/0xd0
  [<ffffffff8100b61f>] arch_cpu_idle+0xf/0x20
  [<ffffffff8105c1db>] cpu_startup_entry+0x25b/0x360
  [<ffffffff812c726e>] rest_init+0xbe/0xd0
  [<ffffffff816a4dcb>] start_kernel+0x339/0x346
  [<ffffffff816a4495>] x86_64_start_reservations+0x2a/0x2c
  [<ffffffff816a4589>] x86_64_start_kernel+0xf2/0xf6
 HELP : loglevel(0-9) reboot(b) crash(c) show-all-locks(d) te...

Before ebade5e8 ("serial: 8250: Clean up the locking for -rt")
this was handled by not even attempting to try the lock if port->sysrq,
since it is known to be taken by the interrupt handler; see
https://bugzilla.kernel.org/show_bug.cgi?id=6716#c1

.  Restore that
behavior.

Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Since most drivers interpret UPIO_MEM32 to mean "little-endian" and use
readl/writel to access the registers, add a parallel UPIO_MEM32BE to
request the use of big-endian MMIO accessors (ioread32be/iowrite32be).

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Hardcoded FIFO size can cause hardware performance limitation.
Using real size value provides better FIFO usage.

Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

If we have fifosize set in driver data we prefer to use it instead of default
fifosize value (which is always 16). If there is defined fifosize for particular
serial we prefer to use it, otherwise we use value from info, which is
common for all serials on given platform.

Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Split lines longer than 80 chars and remove unnecessary whitespaces.

Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch adds waiting until transmit buffer and shifter will be empty
before clock disabling.

Without this fix it's possible to have clock disabled while data was
not transmited yet, which causes unproper state of TX line and problems
in following data transfers.

Cc: <stable@vger.kernel.org> # v2.6.26+
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Return a negative error code on failure.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/

)

// <smpl>
@@
identifier ret; expression e1,e2;
@@
(
if (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The tty break and error flags are not bit masks so do not to use bitwise
OR when assigning them.

Note that there is no functional change due to the if-else construct and
flag having been initialised to zero (TTY_NORMAL).

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The original driver fixed the io address with 0xe000+idx*8,
but real io address assigned from BIOS is dynamically from
read PCI configure space 0x24, 0x20, 0x1c.

The Fintek F81504/F81508/F81512 maybe malfunction without
this patch and malfunction surely when more then 1 PCI card.

Signed-off-by: Peter Hung <hpeter+linux_kernel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tx_empty() should test whether both the transmitter fifo and shifter
for the port is empty, ie. the whole last char was transmitted.
The shift register is empty if AUART_STAT_BUSY is cleared.
The patch fixes the function against the shift register.

According to i.MX23 and i.MX28 Reference Manual:
AUART_STAT_TXFE:
 TX FIFO or transmit holding register is empty.

AUART_STAT_BUSY:
 AUART still transmits bits.
 The BUSY signal goes HIGH as soon as the data is written to the
 transmit FIFO (that is, the FIFO is non-empty) and remains asserted
 HIGH while data is being transmitted.
 BUSY is negated only when the transmit FIFO is empty, and the last
 character has been transmitted from the shift register, including
 the stop bits.

Signed-off-by: Janusz Uzycki <j.uzycki@elproma.com.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>