while using SCC as uart and as serial console at same time I got this:

[  138.214258] Oops: kernel access of bad area, sig: 11 [#1]
[  138.218832] PREEMPT
[  138.221021] NIP: C0105C48 LR: C0105E60 SP: C03D5D10 REGS: c03d5c60 TRAP: 0300    Not tainted
[  138.229280] MSR: 00009032 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 11
[  138.234713] DAR: 00000000, DSISR: C0000000
[  138.238745] TASK = c0349420[693] 'sh' THREAD: c03d4000
[  138.243754] Last syscall: 6
[  138.246402] GPR00: FEFFFFFF C03D5D10 C0349420 C01FB094 00000011 00000000 C1ECFBBC C01F24B0
[  138.254602] GPR08: FF002820 00000000 FF0028C0 00000000 19133615 A0CBCD5E 02000300 00000000
[  138.262804] GPR16: 00000000 01FF9E4C 00000000 7FA9A770 00000000 00000000 1003E2A8 00000000
[  138.271003] GPR24: 100562F4 7F9B6EF4 C0210000 C02A5338 C01FB094 00000000 C01FB094 C1F14574
[  138.279376] NIP [c0105c48] cpm_uart_tx_pump+0x4c/0x22c
[  138.284419] LR [c0105e60] cpm_uart_start_tx+0x38/0xb0
[  138.289361] Call trace:
[  138.291762]  [c0105e60] cpm_uart_start_tx+0x38/0xb0
[  138.296547]  [c010277c] uart_send_xchar+0x88/0x118
[  138.301244]  [c01029a0] uart_unthrottle+0x6c/0x138
[  138.305942]  [c00ece10] check_unthrottle+0x60/0x64
[  138.310641]  [c00ecec4] reset_buffer_flags+0xb0/0x138
[  138.315595]  [c00ecf64] n_tty_flush_buffer+0x18/0x78
[  138.320465]  [c00e81b0] tty_ldisc_flush+0x64/0x7c
[  138.325078]  [c010410c] uart_close+0xf0/0x2c8
[  138.329348]  [c00e9c48] release_dev+0x724/0x8d4
[  138.333790]  [c00e9e18] tty_release+0x20/0x3c
[  138.338061]  [c006e544] __fput+0x178/0x1e0
[  138.342076]  [c006c43c] filp_close+0x54/0xac
[  138.346261]  [c0002d90] ret_from_syscall+0x0/0x44
[  138.352386] note: sh[693] exited with preempt_count 2

a easy way to reproduce it is log into the system using ssh and do:
	cat >/dev/ttyCPM0
then, switch to minicom and write some stuff on it back to ssh, a control C
produce the oops

this happens because uart_close calls uart_shutdown which frees xmit.buf,
currently used by xchar sending in cpm_uart_tx_pump(), which seems wrong.

the attached patch fixes the oops and also fixes xchar sending.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The pre-parsed addrs/n_addrs fields in struct device_node are finally
gone. Remove the dodgy heuristics that did that parsing at boot and
remove the fields themselves since we now have a good replacement with
the new OF parsing code. This patch also fixes a bunch of drivers to use
the new code instead, so that at least pmac32, pseries, iseries and g5
defconfigs build.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Also add a nr_uarts module option to the 8250 code to override
this, up to a maximum of CONFIG_SERIAL_8250_NR_UARTS

This should appease people who complain about a proliferation
of /dev/ttyS & /sysfs nodes whilst at the same time allowing
a single kernel image to support the rarer occasions of
lots of devices.
Signed-off-by: NDave Jones <davej@redhat.com>

Jim Alexander reported a problem where "if one calls open() in
blocking mode with CLOCAL off, the 8250.c driver under the 2.6
kernel (or at least 2.6.8 and 2.6.10) does not wake up the
blocked process when DCD is asserted."

Fix this by enabling modem status interrupts immediately before
we read the carrier detect status.

Thanks to Jim for reporting the problem and testing the fix.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This is needs to be visible to other architectures using the AMBA
bus and peripherals.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Since the ARM AMBA bus is used on MIPS as well as ARM, we need
to make the bus available for other architectures to use.  Move
the AMBA include files from include/asm-arm/hardware/ to
include/linux/amba/
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Before this patch we were just using the "classic" /dev/ttySx devices.
However when another on the system is loaded that uses those (like drivers for
serial PCMCIA), that creates a conflict for the minors.  Therefore, we now use
/dev/ttyPSC[0:5] (note the 0-based numbering !) with some minors we've been
assigned in the "Low Density Serial port major"
Signed-off-by: NSylvain Munaut <tnt@246tNt.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NWolfgang Denk <wd@denx.de>
Signed-off-by: NSylvain Munaut <tnt@246tNt.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Unify the EVENT_CARD_INSERTION and "attach" callbacks to one unified
probe() callback. As all in-kernel drivers are changed to this new
callback, there will be no temporary backwards-compatibility. Inside a
probe() function, each driver _must_ set struct pcmcia_device
*p_dev->instance and instance->handle correctly.

With these patches, the basic driver interface for 16-bit PCMCIA drivers
now has the classic four callbacks known also from other buses:

        int (*probe)            (struct pcmcia_device *dev);
        void (*remove)          (struct pcmcia_device *dev);

        int (*suspend)          (struct pcmcia_device *dev);
        int (*resume)           (struct pcmcia_device *dev);
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

The linked list of devices managed by each PCMCIA driver is, in very most
cases, unused. Therefore, remove it from many drivers.
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

Unify the "detach" and REMOVAL_EVENT handlers to one "remove" function.
Old functionality is preserved, for the moment.
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

Move the suspend and resume methods out of the event handler, and into
special functions. Also use these functions for pre- and post-reset, as
almost all drivers already do, and the remaining ones can easily be
converted.

Bugfix to include/pcmcia/ds.c
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

_INLINE_ went away.
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

All call sites for serial8250_handle_port() acquired the port spinlock
and released it afterwards.  This is a needless duplication of code.
Move the spinlocking inside serial8250_handle_port().
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The function uart_match_port() incorrectly compares the ioremap'd
virtual addresses of ports instead of the physical address to find
duplicate ports for MMIO based UARTs. This fixes it.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

I've also fixed the sort-ordering comments on this naming convention.
Signed-off-by: NStuart MacDonald <stuartm@connecttech.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Reading the MSR register on 8250-compatible UARTs results in any
modem status interrupts being cleared.  To avoid missing any
status changes, arrange for get_mctrl() to read the current
status via check_modem_status(), which will process any pending
state changes for us.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

It seems that clk_use() and clk_unuse() are additional complexity
which isn't required anymore.  Remove them from the clock framework
to avoid the additional confusion which they cause, and update all
ARM machine types except for OMAP.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Erik Hovland

This patch provides two changes. An indent is supplied for an if/else clause so that it is more readable. An acronym is incorrectly typed as UER when it should be IER.
Signed-off-by: NErik Hovland <erik@hovland.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

We only want the received character without the status bits for
sysrq handling.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Introduce a Kconfig symbol SPARC that is defined on both the sparc and
sparc64 architectures.

This symbol makes some dependencies more readable.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDave Jones <davej@redhat.com>

This patch marks a few serial data structures const, moving them to
.rodata where they won't false-share cachelines with things that get
written to.
Signed-off-by: NArjan van de Ven <arjan@infradead.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Since the spinlock was removed from sa1100_start_tx(), the "flags"
variable becomes redundant.  Remove it.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The receiver status register reports latched error conditions, which
must be cleared by writing to it.  However, the data register reports
unlatched conditions which are associated with the current character.
Use the data register to interpret error status rather than the RSR.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Depend on GSC, not PARISC.  Machines without GSC don't have a MUX.
Signed-off-by: NMatthew Wilcox <willy@parisc-linux.org>
Signed-off-by: NKyle McMartin <kyle@parisc-linux.org>

This commit is in response to a bug reported by Vesa on the irc channel
a couple of weeks ago.

The bug was that the console would apparently hang (not return) while
using the mux console.

The root cause of this bug is that bash (with readline support) makes a
call to the tcsetattr() glibc function with the argument TCSADRAIN.  This
causes the serial core in the kernel use the uart_wait_until_sent() to be
called. This function verifies the mux transmit queue is empty or calls the
msleep_interruptable() with a calculated timeout value that is dependant
upon the port->timeout variable.

The real problem here is that the port->timeout was not defined so it
was defaulted to 0 and the timeout calculation performs the following
calculation:

char_time = (port->timeout - HZ/50) / port->fifosize;

where char_time is an unsigned long. Since the serial Mux does not use
interrupts, the msleep_interruptable() function waits until the timeout
has been reached ... and when the port->timeout < HZ/50 this timeout will
be a long time. (I have validated that the console will eventually
return ... but it takes quite a while for this to happen).

This patch simply sets the port->timeout on the Mux to HZ/50 to avoid
this long timeout period.
Signed-off-by: NRyan Bradetich <rbrad@parisc-linux.org>
Signed-off-by: NKyle McMartin <kyle@parisc-linux.org>

This patch does the following:
* Fixes compiler warnings.
* Replaces a __raw_readl call with the existing macro.
Signed-off-by: NRyan Bradetich <rbrad@parisc-linux.org>
Signed-off-by: NKyle McMartin <kyle@parisc-linux.org>

Changed jobs and the Freescale address is no longer valid.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Since few people need the support anymore, this moves the legacy
pm_xxx functions to CONFIG_PM_LEGACY, and include/linux/pm_legacy.h.
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

If we fail to re-startup a serial port on resume, shut it down
immediately and mark it as an error condition.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The serial core aquires the port spinlock before calling
port->ops->start_tx(), so sa1100_start_tx() shouldn't try to lock it
again.

BUG: spinlock recursion on CPU#0, init/1
 lock: c0205f20, .magic: dead4ead, .owner: init/1, .owner_cpu: 0
[<c0022cdc>] (dump_stack+0x0/0x14) [<c00dc338>] (spin_bug+0x0/0xbc)
[<c00dc6b0>] (_raw_spin_lock+0x0/0x170)  r8 = 00000007  r7 = C02FE0070
[<c018a2a8>] (_spin_lock_irqsave+0x0/0x24)  r4 = C0205F20
[<c0112110>] (sa1100_start_tx+0x0/0x40)  r4 = C038C000
[<c010ee38>] (__uart_start+0x0/0x5c) [<c010ee94>] (uart_start+0x0/0x3
[<c010f1d0>] (uart_write+0x0/0xdc) [<c00fee34>] (write_chan+0x0/0x370
Signed-off-by: NFlorin Malita <fmalita@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Claim the WACF005 device.  This is the pen display pointing device on
the HP Compaq tc1100 Tablet PC.  More information about using this
device, including using it as an X pointer device:

    http://www.theory.bham.ac.uk/staff/schofield/linux/tc1100/

Christopher Kemp <ck231@cam.ac.uk> did the legwork of determining that
the WACF005 is really just a plain old UART and doing an initial ACPI
driver (before we had PNPACPI), and David Ludlow <dave@adsllc.com>
confirmed that PNPACPI + the attached patch is now sufficient:

    pnp: Device 00:05 activated.
    ttyS4 at I/O 0x300 (irq = 4) is a 16550A
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Fix copy-paste bug in mpc52xx_uart.c (pdev<->dev)
Signed-off-by: NAndrey Volkov <avolkov@varma-el.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Use physical addresses at the interface level, letting drivers remap
them as appropriate.
Signed-off-by: NMaciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

xscale-type UARTs have an extra bit (UUE) in the IER register that has
to be written as 1 to enable the UART.  At the end of autoconfig() in
drivers/serial/8250.c, the IER register is unconditionally written as
zero, which turns off the UART, and makes any subsequent printch() hang
the box.

Since other 8250-type UARTs don't have this enable bit and are thus
always 'enabled' in this sense, it can't hurt to enable xscale-type
serial ports all the time as well.  The attached patch changes the
autoconfig() exit path to see if the port has an UUE enable bit, and if
yes, to write UUE=1 instead of just putting a zero into IER, using the
same test as is used at the beginning of serial8250_console_write().
Signed-off-by: NLennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>