This patch fixes a build failure [1-4] in the atmel_serial code introduced by
patch the patch ARM: 6092/1: atmel_serial: support for RS485
communications (e8faff73)

The build failure was caused by missing struct field and missing defines
for the avr32 board - the patch fixes this.

[1] http://kisskb.ellerman.id.au/kisskb/buildresult/2575242/ - first failure in linux-next, may 11th
[2] http://kisskb.ellerman.id.au/kisskb/buildresult/2816418/ - still exists as of today
[3] http://kisskb.ellerman.id.au/kisskb/buildresult/2617511/ - first failure in Linus' tree - May 20th - did really no one notice this?!
[4] http://kisskb.ellerman.id.au/kisskb/buildresult/2813956/ - still exists in Linus' tree as of today
Signed-off-by: NPeter Huewe <peterhuewe@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Final version of the patch that adds support for RS485 communications to the atmel_serial driver.

The patch has been already sent and discussed on both linux-kernel and linux-arm-kernel mailing lists several times.

Many people collaborated to improve and test the code:
Tested-by: NSebastian Heutling <Sebastian.Heutling@who-ing.de>
Tested-by: NBernhard Roth <br@pwrnet.de>
Reviewed-by: NRyan Mallon <ryan@bluewatersys.com>
Signed-off-by: NClaudio Scordino <claudio@evidence.eu.com>
Signed-off-by: NMichael Trimarchi <michael@evidence.eu.com>
Signed-off-by: NRick Bronson <rick@efn.org>
Signed-off-by: NSebastian Heutling <Sebastian.Heutling@who-ing.de>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Permits using KGDB over the console with the atmel_serial driver.

[akpm@linux-foundation.org: s/barrier/cpu_relax/]
Signed-off-by: NAlbin Tonnerre <albin.tonnerre@free-electrons.com>
Acked-by: NAndrew Victor <linux@maxim.org.za>
Acked-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

is_power_of_2() appears not to be constant enough for BUILD_BUG_ON()
after the latest rework, so replace it with an open-coded test.
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Claudio Scordino <claudio@evidence.eu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is used by various drivers not just serial and can be extracted
as commonality
Signed-off-by: NAlan Cox <alan@linux.intel.com>

We moved this into uart_state, now move the fields out of the separate
structure and kill it off.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/serial/atmel_serial.c: fix compile when CONFIG_SERIAL_ATMEL=Y and CONFIG_SERIAL_ATMEL_CONSOLE=N

When SERIAL_ATMEL_CONSOLE is disabled, ATMEL_CONSOLE_DEVICE is set to
NULL, and trying to access ATMEL_CONSOLE_DEVICE->flags in
atmel_serial_probe makes the compile fail.  This fixes the issue by only
accessing it if CONFIG_SERIAL_ATMEL_CONSOLE is defined
Signed-off-by: NAlbin Tonnerre <albin.tonnerre@free-electrons.com>
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

After enabling hardware flow control, any subsequent termios call may hang
waiting for the transmitter to drain.  This appears to be caused by a
busy-loop in set_termios() waiting for the transmitter to become empty,
which may take a very long time (or hang indefinitely) if the device at
the other end is blocking us.

A quick look through the tty and serial_core code indicates that any
necessary flushing (which is optional) has already been done at this
point, so there's no need for the driver to flush the transmitter on its
own.

Fix it by removing the busy-loop altogether.
Tested-by: NEirik Aanonsen <eaa@wprmedical.com>
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Adds Hardware Handshake (aka RTS/CTS flow-control) support to
atmel_serial driver, as a termios flag.

For this to actually work, the platform code needs to configure the RTS
and CTS pins for use by the USART. This has been done for AVR32 as a
separate patch.
Signed-off-by: NPeter Ma <pma@mediamatech.com>
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>

I found a problem of handling of modem status of atmel_serial driver.

With the commit 1ecc26 ("atmel_serial: split the interrupt handler"),
handling of modem status signal was splitted into two parts.  The
atmel_tasklet_func() compares new status with irq_status_prev, but
irq_status_prev is not correct if signal status was changed while the port
is closed.

Here is a sequence to cause problem:

1. Remote side sets CTS (and DSR).
2. Local side close the port.
3. Local side clears RTS and DTR.
4. Remote side clears CTS and DSR.
5. Local side reopen the port.  hw_stopped becomes 1.
6. Local side sets RTS and DTR.
7. Remote side sets CTS and DSR.

Then CTS change interrupt can be received, but since CTS bit in
irq_status_prev and new status is same, uart_handle_cts_change() will not
be called (so hw_stopped will not be cleared, i.e.  cannot send any data).

I suppose irq_status_prev should be initialized at somewhere in open
sequence.

Itai Levi pointed out that we need to initialize atmel_port->irq_status
as well here. His analysis is as follows:

> Regarding the second part of the patch (which resets irq_status_prev),
> it turns out that both versions of the patch (mine and Atsushi's)
> still leave enough room for faulty behavior when opening the port.
>
> This is because we are not resetting both irq_status_prev and
> irq_status in atmel_startup() to CSR, which leads faulty behavior in
> the following sequences:
>
> First case:
> 1. closing the port while CTS line = 1 (TX not allowed)
> 2. setting CTS line = 0 (TX allowed)
> 3. opening the port
> 4. transmitting one char
> 5. Cannot transmit more chars, although CTS line is 0
>
> Second case:
> 1. closing the port while CTS line = 0 (TX allowed)
> 2. setting CTS line = 1 (TX not allowed)
> 3. opening the port
> 4. receiving some chars
> 5. Now we can transmit, although CTS line is 1
>
> This reason for this is that the tasklet is scheduled as a result of
> TX or RX interrupts (not a status change!), in steps 4 above. Inside
> the tasklet, the atmel_port->irq_status (which holds the value from
> the previous session) is compared to atmel_port->irq_status_prev.
> Hence, a status-change of the CTS line is faultily detected.
>
> Both cases were verified on 9260 hardware.

[haavard.skinnemoen@atmel.com: folded with patch from Itai Levi]
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Remy Bohmer <linux@bohmer.net>
Cc: Marc Pignat <marc.pignat@hevs.ch>
Cc: Itai Levi <itai.levi.devel@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix the following problem, related to hardware flow control (CTS/RTS):
Transmitting while CTS line is asserted in DMA mode, due to not checking
for tx-stopped condition.

We found these problems while testing the UARTs with hardware
flow-control.
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: "Andrew Victor" <avictor.za@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The atmel_serial driver is mismanaging its clock by leaving it on at all
times ...  the whole point of clock management is to leave it off unless
it's actively needed, which conserves power!!

Although the kernel doesn't actually hang without my fix, it does
discard quite a lot of early console output.

The result still looks correct:

          usart        users= 1 on   35000000 Hz, for atmel_usart.0
          usart        users= 0 off  35000000 Hz, for atmel_usart.2

when using ttyS0 as serial console.

[haavard.skinnemoen@atmel.com: Make sure clock is enabled early for console]
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This problem seems to be unnoticed so far:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=b3b708fa2780cd2b5d8266a8f0c3a1cab364d4d2

has changed the serial core behavior to not to suspend the port if the
device is enabled as a wakeup source.  If the AT91 system goes to slow
clock mode, the port should be suspended always and the clocks should be
switched off.  The patch attached updates the atmel_serial driver to match
the changes in serial core.

Also, the interrupts are disabled when the clock is disabled.  If we
disable the clock with interrupts enabled, an interrupt may get stuck.  If
this is the DBGU interrupt, this blocks the OR logic at system controller
and thus all other sysc interrupts.
Signed-off-by: NAnti Sullin <anti.sullin@artecdesign.ee>
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Michael Trimarchi <trimarchimichael@yahoo.it>
Cc: Andrew Victor <linux@maxim.org.za>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This just leaves include/asm-arm/plat-* to deal with.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The tty pointer has been moved into a tty_port field, so we need to use
->info->port.tty instead of just ->info->tty. Fixes these build errors:

David Brownell <david-b@pacbell.net> wrote:
> drivers/serial/atmel_serial.c: In function 'atmel_rx_from_ring':
> drivers/serial/atmel_serial.c:665: error: 'struct uart_info' has no member named 'tty'
> drivers/serial/atmel_serial.c: In function 'atmel_rx_from_dma':
> drivers/serial/atmel_serial.c:672: error: 'struct uart_info' has no member named 'tty'
> drivers/serial/atmel_serial.c: In function 'atmel_startup':
> drivers/serial/atmel_serial.c:797: error: 'struct uart_info' has no member named 'tty'
> make[2]: *** [drivers/serial/atmel_serial.o] Error 1
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Avoid dumping garbage to the serial port when the tty is flushed. This
tends to happen when rebooting from a serial console.
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Acked-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Funny things may happen if we stop the USART clock before the shifter is
empty. Prevent this from happening by waiting until the shifter is
completely drained before allowing suspend to continue.
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Andrew Victor <linux@maxim.org.za>

AVR32 doesn't have at91_suspend_entering_slow_clock(). Just assume the
clock will keep running for now.

David has a better solution for this, but this works for now. Leaving
the USART clock running won't prevent the PM code from entering deep
power-down modes anyway.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: Andrew Victor <linux@maxim.org.za>

I made a change to u-boot that used the FP (Fractional Part) field of BRGR
to achieve more accurate baud rate generation.  Unfortunately, the
atmel_serial driver looks at the whole BRGR register when trying to detect
the baud rate that the port is currently running at, so setting FP to a
nonzero value breaks the baud rate detection.

I'll sit on the u-boot patch for a while longer, but this is clearly a
bug in the atmel_serial driver which should be fixed.
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Acked-by: NAndrew Victor <linux@maxim.org.za>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

After commit 39d4c922 (atmel_serial: fix
uart/console concurrent access) the UART_GET_TCR macro got redefined. This
patch removes the duplicated definition.
Signed-off-by: Nmichael trimarchi <trimarchimichael@evidence.eu.com>
Acked-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since 43cc71ee, the platform modalias is
prefixed with "platform:".  Add MODULE_ALIAS() to the hotpluggable serial
platform drivers, to re-enable auto loading.

NOTE that Kconfig for some of these drivers doesn't allow modular builds, and
thus doesn't match the driver source's unload support.  Presumably their
unload code is buggy and/or weakly tested...

[dbrownell@users.sourceforge.net: more drivers, registration fixes]
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Acked-by: NPeter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Strange chars appear on the serial port when a printk and a printf
happens at the same time.  This is caused by the pdc sending chars while
atmel_console_write (called from printk) is executing

Concurent access of uart and console to the same port leads to corrupted
data to be transmitted, so disable tx dma (PDC) while writing to the
console.
Signed-off-by: NMarc Pignat <marc.pignat@hevs.ch>
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I found a problem related to losing data during pdc transmission in
atmel_serial: connect ttyS1 with ttyS2 using a loopback cable, send 30
byte of packet from one to the other and waiting for 30 byte.  On the
other side just read and echo the data received.

We always call atmel_tx_dma() from the tasklet regardless of what interrupt
triggered it.
Signed-off-by: Nmichael <trimarchi@gandalf.sssup.it>
Acked-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We should only return IRQ_HANDLED when we actually found something to
handle. This is important since the USART interrupt handler may be
shared with the timer interrupt on some chips.
Pointed-out-by: Nmichael <trimarchi@gandalf.sssup.it>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When possible, pass the tty name to request_irq() so that the user can easily
distinguish the different serial ports in /proc/interrupts.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Victor <linux@maxim.org.za>
Tested-by: NMarc Pignat <marc.pignat@hevs.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As pointed out by David Brownell, we really ought to be using container_of
when converting from "struct uart_port *" to "struct atmel_uart_port *".
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Victor <linux@maxim.org.za>
Tested-by: NMarc Pignat <marc.pignat@hevs.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Introduced by atmel_serial-split-the-interrupt-handler.patch.

Thanks to michael <trimarchi@gandalf.sssup.it> for spotting it.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch is based on the DMA-patch by Chip Coldwell for the AT91/AT32 serial
USARTS, with some tweaks to make it apply neatly on top of the other patches
in this series.

The RX and TX code has been moved to a tasklet and reworked a bit.  Instead of
depending on the ENDRX and TIMEOUT bits in CSR, we simply grab as much data as
we can from the DMA buffers.  I think this closes a race where the ENDRX bit
is set after we read CSR but before we read RPR, although I haven't confirmed
this.

Similarly, the two TX handlers (ENDTX and TXBUFE) have been combined into one.
 Since the current code only uses a single TX buffer, there's no point in
handling those interrupts separately.

This also fixes a DMA sync bug in the original patch.

[linux@bohmer.net: rebased onto irq-splitup patch]
[hskinnemoen@atmel.com: moved to tasklet, fixed dma bug, misc cleanups]
[hskinnemoen@atmel.com: atmel_serial dma: Misc fixes and cleanups]
Signed-off-by: NRemy Bohmer <linux@bohmer.net>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Victor <linux@maxim.org.za>
Tested-by: NMarc Pignat <marc.pignat@hevs.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Split up the interrupt handler of the serial port into a interrupt top-half
and a tasklet.

The goal is to get the interrupt top-half as short as possible to minimize
latencies on interrupts.  But the old code also does some calls in the
interrupt handler that are not allowed on preempt-RT in IRQF_NODELAY context.
This handler is executed in this context because of the interrupt sharing with
the timer interrupt.  The timer interrupt on Preempt-RT runs in IRQF_NODELAY
context.

The tasklet takes care of handling control status changes, pushing incoming
characters to the tty layer, handling break and other errors.  It also handles
pushing TX data into the data register.

Reading the complete receive queue is still done in the top-half because we
never want to miss any incoming character.

[hskinnemoen@atmel.com: misc cleanups and simplifications]
Signed-off-by: NRemy Bohmer <linux@bohmer.net>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Victor <linux@maxim.org.za>
Tested-by: NMarc Pignat <marc.pignat@hevs.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When an error happens in probe(), the clocks should be disabled, but
only if the port isn't already used as a console.

In remove(), the port struct shouldn't be freed because it's defined
statically.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Victor <linux@maxim.org.za>
Tested-by: NMarc Pignat <marc.pignat@hevs.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If BRGR is zero, the baud rate generator isn't running, so the boot loader
can't have initialized the port.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: NAndrew Victor <linux@maxim.org.za>
Tested-by: NMarc Pignat <marc.pignat@hevs.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Replace two instances of barrier() with cpu_relax() since that's the right
thing to do when busy-waiting.  This does not actually change anything since
cpu_relax() is defined as barrier() on both ARM and AVR32.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: NAndrew Victor <linux@maxim.org.za>
Tested-by: NMarc Pignat <marc.pignat@hevs.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Clean up the atmel_serial driver to conform the coding rules.  It contains no
functional change.
Signed-off-by: NRemy Bohmer <linux@bohmer.net>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: NAndrew Victor <linux@maxim.org.za>
Tested-by: NMarc Pignat <marc.pignat@hevs.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently early kernel messages, i.e., those from uncompression, go to the
debugging UART. And if it is enabled in the platform configuration, but
not initialized by the bootloader, the machine hangs, waiting for UART
status change. Besides, having those messages on another UART - typically
the console UART - may be preferrable. This patch allows selecting the
UART in kernel configuration.
Signed-off-by: NGuennadi Liakhovetski <lg@denx.de>
Acked-by: NAndrew Victor <linux@maxim.org.za>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Remove annoying build warnings about unused variables in atmel_serial,
which afflict both AT91 and AVR32 builds.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Acked-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The RXBRK field in the AT91/AT32 USART status register has the
following definition according to e.g. the AT32AP7000 data sheet:

    RXBRK: Break Received/End of Break
    0: No Break received or End of Break detected since the last RSTSTA.
    1: Break Received or End of Break detected since the last RSTSTA.

Thus, for each break, the USART sets the RXBRK bit twice. This patch
modifies the driver to report the break event to the serial core only
once by keeping track of whether a break condition is currently
active. The break_active flag is reset as soon as a character is
received, so even if we miss the start-of-break interrupt this should
do the right thing.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Victor <andrew@sanpeople.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ivan Kuten <ivan.kuten@promwad.com>
Cc: Nicolas Ferre <nicolas.ferre@rfo.atmel.com>
Cc: Patrice Vilchez <patrice.vilchez@rfo.atmel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Allow slower serial baud-rates by switching the UART clock from MCK to
MCK/8.

Based on patches by Mike Wolfram and Russell King.
Signed-off-by: NAndrew Victor <andrew@sanpeople.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Access to chip-internal registers should always be native-endian.  This is
especially important for AVR32 since it's a big-endian architecture and the
non-raw readl() and writel() macros are defined to do little-endian
accesses.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: NAndrew Victor <andrew@sanpeople.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The Atmel AT91 and AVR32 processor architectures share many of the same
peripherals.  The PDC (Peripheral Data Controller) registers are also
implemented within in a number of the on-chip peripherals (eg, USART,
MMC, SPI, SSC, etc).

In a attempt not to duplicate the register definitions in each
peripheral, or in each architecture, the at91_pdc.h header in
asm-arm/arch-at91 and asm-avr32/arch-at32ap has been replaced with
linux/atmel_pdc.h.

The definitions have also been renamed from AT91_PDC_* to ATMEL_PDC_*,
and the drivers updated accordingly.

Original patch from Nicolas Ferre.
Signed-off-by: NAndrew Victor <andrew@sanpeople.com>
Acked-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch fixes the unbalanced calls to enable_irq_wake() and
disable_irq_wake() in the AT91 (and AVR32) serial driver.

It should resolve these kernel messages:
  Unbalanced IRQ x wake disable
  BUG: warning at kernel/irq/manage.c:167/set_irq_wake()

Original patch from Marc Pignat.
Signed-off-by: NAndrew Victor <andrew@sanpeople.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>