Running a serial console, if too many kernel messages are generated within
a short time causing a lot of serial I/O, the 8250 driver will generate
another kernel message reporting this, which just adds to the I/O. It has
a cascading effect and quickly results the system being brought to its knees
by a flood of "too much work" messages.

Ratelimit the error message to avoid this.

[akpm@linux-foundation.org: use the superior printk_ratelimited()]
[akpm@linux-foundation.org: printk_ratelimited() needs ratelimit.h]
Signed-off-by: NDaniel Drake <dsd@laptop.org>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The actual uart baud rate of devices vary between +/-2% of what is
asked.  The SPORT RX sample rate should be faster than double of the
worst case.  Otherwise, wrong data may be received.  So set SPORT RX
clock to be 3% faster in general.
Reported-by: NOlivier STOCK <ostockemer@ereca.fr>
Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Not every platform that has generic legacy 8250 ports manages to have them
clocked the right way or without errata. Provide a generic interface to
allow platforms to override the default behaviour in a manner that dumps
the complexity in *their* code not the 8250 driver.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NDirk Brandewie <dirk.brandewie@gmail.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The .start_tx callback (imx_start_tx here) isn't only called when the
buffer is non-empty.  E.g. after resume or when handshaking is enabled
and the other side starts to signal being ready.

So check for an empty puffer already before sending the first character.
This prevents sending out stale (or uninitialised) data.
Signed-off-by: NVolker Ernst <volker.ernst@txtr.com>
Signed-off-by: NDaniel Mack <daniel@caiaq.de>
Cc: Andy Green <andy@warmcat.com>
[ukl: reword commit log, put check in while condition]
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add more baud rates support referring the baud_table[] defined
in drivers/char/tty_ioctl.c: 3000000/2000000/1000000/500000
Signed-off-by: NFeng Tang <feng.tang@intel.com>
Acked-by: NAlan Cox <alan.cox@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

If kzmalloc fails, the uart port is not removed causing a leak.
This patch just add another label that removes the uart when the
kzmalloc fails.
Signed-off-by: NBreno Leitao <leitao@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Custom UART PM hook for Alchemy chips:  do standard UART pm and
additionally en/disable uart block clocks as needed.
This allows to get rid of a debug port PM hack in the Alchemy pm code.

Tested on Db1200.
Signed-off-by: NManuel Lauss <manuel.lauss@googlemail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add a hook for platforms to specify custom pm methods.
Signed-off-by: NManuel Lauss <manuel.lauss@googlemail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Fixes sparse warning.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>

Simply add an early_altera_uart_setup() prototype declaration, otherwise
platform code have to do it in .c files, which is ugly.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

port->flags is of type upf_t, which corresponds to UPF_* flags.

ASYNC_BOOT_AUTOCONF is an unsigned integer, which happen to
be the same as UPF_BOOT_AUTOCONF.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This fixes tty name, major and minor numbers. The major number
204 is used across many platform-specific serial drivers, so we
use that.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Some controllers implement registers with a stride, to support
those we must implement the proper IO accessors.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This makes it much easier to integrate the driver with the rest of
the Linux (e.g. MFD subsystem).

The old method is still supported though.

Also, from now on, there is one platform device per port (no
changes are needed for the platform code, as no one registers
the devices anywhere in-tree yet).
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>,
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Some Altera UART implementations doesn't route the IRQ line, so we have
to work in polling mode.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Soon we will use that handy function in the altera_uart driver.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Clearly I have gone insane, so I might as well tell the world about it.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The loop in wait_for_xmitr() is delaying one extra uS after the ready
condition has been met.  Rewrite the loop to only delay if the
transmitter is not ready.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Soott Kilau is handing off the maintainership of the jsm serial
driver to me, and this patch just add the driver as maintained.
Signed-off-by: NBreno Leitao <leitao@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

A notifier chain is called whenever the vt code modifies a terminal
content, except for one case which is when the modification comes
through writes to /dev/vcs* devices.  Let's add the missing notifier
invocation at the end of vcs_write() for that case too.
Signed-off-by: NNicolas Pitre <nicolas.pitre@canonical.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The /dev/vcs* devices are used, amongst other things, by accessibility
applications such as BRLTTY to display the screen content onto refreshable
braille displays.  Currently this is performed by constantly reading from
/dev/vcsa0 whether or not the screen content has changed.  Given the
default braille refresh rate of 25 times per second, this easily qualifies
as the biggest source of wake-up events preventing laptops from entering
deeper power saving states.

To avoid this periodic polling, let's add support for select()/poll() and
SIGIO with the /dev/vcs* devices.  The implemented semantic is to report
data availability whenever the corresponding vt has seen some update after
the last read() operation.  The application still has to lseek() back
as usual in order to read() the new data.

Not to create unwanted overhead, the needed data structure is allocated
and the vt notification callback is registered only when the poll or
fasync method is invoked for the first time per file instance.
Signed-off-by: NNicolas Pitre <nicolas.pitre@canonical.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add a new file /proc/tty/consoles to be able to determine the registered
system console lines.  If the reading process holds /dev/console open at
the regular standard input stream the active device will be marked by an
asterisk.  Show possible operations and also decode the used flags of
the listed console lines.
Signed-off-by: NWerner Fink <werner@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Again basically cut and paste

Convert the main driver set to use the hooks for GICOUNT
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Simple pasting job using the new ops function. Also fix a couple of devices
directly returning the internal struct (which happens at this point to match
for the fields that matter but isn't correct or futureproof)
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Dan Rosenberg noted that various drivers return the struct with uncleared
fields. Instead of spending forever trying to stomp all the drivers that
get it wrong (and every new driver) do the job in one place.

This first patch adds the needed operations and hooks them up, including
the needed USB midlayer and serial core plumbing.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Fix memory leaks in max3107_probe() when returning on error.
Signed-off-by: NDavidlohr Bueso <dave@gnu.org>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

And while we are at it allow it to fail to find one. Without this the IRQ
option will cause the 3110 driver to fail on 0.7 SFI firmware.
Acked-by: NFeng Tang <feng.tang@intel.com>
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The cleanup for mrst_max3110 includes:
* remove unneeded head files
* make the spi_transfer dma safe, so that driver is more portable
* add more check for error return value
* use mutex_trylock for read thread
Signed-off-by: NFeng Tang <feng.tang@intel.com>
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Function tty_register_device may return ERR_PTR(...). Check for it.
Signed-off-by: NVasiliy Kulikov <segooon@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Vasiliy found that pci_disable_device is not called on fail paths in
mxser_probe. Actually, it is called from nowhere in the driver.

There are three changes needed:
1) don't use pseudo-generic mxser_release_res. Let's use it only from
   ISA paths from now on. All the pci stuff is moved to probe and
   remove PCI-related functions.
2) reorder fail-paths in the probe function so that it makes sense and
   we can call them from the sequential code naturally (the further we
   are the earlier label we go to).
3) add pci_disable_device both to mxser_probe and mxser_remove.

There is a nit of adding CONFIG_PCI ifdef to mxser_remove. it is
because this driver supports ISA-only compilations and it would choke
up on the newly added calls now.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Kulikov Vasiliy <segooon@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Ttyprintk is a pseudo TTY driver, which allows users to make printk
messages, via output to ttyprintk device. It is possible to store
"console" messages inline with kernel messages for better analyses of
the boot process, for example.
Signed-off-by: NSamo Pogacnik <samo_pogacnik@t-2.net>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The commit 4547be78 rewrites suspend and resume functions. According
to this rewrite, when a serial port is a printk console device and
can suspend(without set no_console_suspend flag), it will definitely
call set_termios function during its resume, but parameter termios
isn't initialized, this will pass an unpredictable config to the
serial port. If this serial port is not a userspace opened tty device
, a suspend and resume action will make this serial port unusable.
I.E. ttyS0 is a printk console device, ttyS1 or keyboard+display is
userspace tty device, a suspend/resume action will make ttyS0
unusable.

If a serial port is both a printk console device and an opened tty
device, this issue can be overcome because it will call set_termios
again with the correct parameter in the uart_change_speed function.

Refer to the deleted content of commit 4547be78, revert parts relate
to restore settings into parameter termios. It is safe because if
a serial port is a printk console only device, the only meaningful
field in termios is c_cflag and its old config is saved in
uport->cons->cflag, if this port is also an opened tty device,
it will clear uport->cons->cflag in the uart_open and the old config
is saved in tty->termios.
Signed-off-by: NJason Wang <jason77.wang@gmail.com>
Acked-by: NStanislav Brabec <sbrabec@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The commit 4547be78 rewrites suspend and resume functions, this
introduces a problem on the OMAP3EVM platoform. when the kernel boots
with no_console_suspend and we suspend the kernel, then resume it,
the serial console will be not usable. This problem should be common
for all platforms.
The cause for this problem is that when enter suspend, if we choose
no_console_suspend, the console_stop will be skiped. But in resume
function, the console port will be set to uninitialized state by
calling set_termios function and the console_start is called without
checking whether the no_console_suspend is set, Now fix it.
Signed-off-by: NJason Wang <jason77.wang@gmail.com>
Acked-by: NStanislav Brabec <sbrabec@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch converts s390 to use asm-generic/ioctls.h instead of its
own version.

The differences between the arch-specific version and the generic
version are as follows:

- S390 defines its own value for FIOQSIZE, asm-generic/ioctls.h keeps it
- The generic version adds TIOCGRS485 and TIOCGRS485, which are unused
  by any driver available on this architecture
- The generic version adds support for termiox

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch converts mn10300 to use asm-generic/ioctls.h instead of its
own version.

The differences between the arch-specific version and the generic
version are as follows:

- The generic version provides TIOCGRS485 and TIOCSRS485 but they
  are unused by any driver available for this architecture.
- The generic version adds support for termiox

Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch converts m68k to use asm-generic/ioctls.h instead of its
own version.

The differences between the arch-specific version and the generic
version are as follows:

- m68k defines its own value for FIOQSIZE, asm-generic/ioctls.h keeps it
- The generic version adds TIOCSRS485 and TIOCGRS485m which are unused
  by any driver available on this architecture.
- The generic version adds support for termiox

Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch converts m32r to use asm-generic/ioctls.h instead of its
own version.

The differences between the arch-specific version and the generic
version are as follows:

- The generic version adds TIOCGRS485 and TIOCGRS485, which are unused by
  any driver available on this architecture.
- The generic version adds support for termiox

Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch converts ia64 to use asm-generic/ioctls.h instead of its
own version.

The differences between the arch-specific version and the generic
version are as follows:

- The generic version adds TIOCSRS485 and TIOCGRS485, which are unused
  by any driver available on this architecture.
- The generic version adds support for termiox

Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch converts h8300 to use asm-generic/ioctls.h instead of its
own version.

The differences between the arch-specific version and the generic
version are as follows:

- H8300 defines its own value for FIOQSIZE, asm-generic/ioctls.h keeps it
- The generic version adds TIOCSRS485 and TIOGSRS485, but are unused
  by any driver available on this architecture.
- The generic version adds support for termiox

Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>