This reverts commit b1c43f82c5aa265442f82dba31ce985ebb7aa71c.

It was broken in so many ways, and results in random odd pty issues.

It re-introduced the buggy schedule_work() in flush_to_ldisc() that can
cause endless work-loops (see commit a5660b41af6a: "tty: fix endless
work loop when the buffer fills up").

It also used an "unsigned int" return value fo the ->receive_buf()
function, but then made multiple functions return a negative error code,
and didn't actually check for the error in the caller.

And it didn't actually work at all.  BenH bisected down odd tty behavior
to it:
  "It looks like the patch is causing some major malfunctions of the X
   server for me, possibly related to PTYs.  For example, cat'ing a
   large file in a gnome terminal hangs the kernel for -minutes- in a
   loop of what looks like flush_to_ldisc/workqueue code, (some ftrace
   data in the quoted bits further down).

   ...

   Some more data: It -looks- like what happens is that the
   flush_to_ldisc work queue entry constantly re-queues itself (because
   the PTY is full ?) and the workqueue thread will basically loop
   forver calling it without ever scheduling, thus starving the consumer
   process that could have emptied the PTY."

which is pretty much exactly the problem we fixed in a5660b41af6a.

Milton Miller pointed out the 'unsigned int' issue.

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reported-by: Milton Miller <miltonm@bga.com>
Cc: Stefan Bigler <stefan.bigler@keymile.com>
Cc: Toby Gray <toby.gray@realvnc.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

it makes it simpler to keep track of the amount of
bytes received and simplifies how flush_to_ldisc counts
the remaining bytes. It also fixes a bug of lost bytes
on n_tty when flushing too many bytes via the USB
serial gadget driver.

Tested-by: Stefan Bigler <stefan.bigler@keymile.com>
Tested-by: Toby Gray <toby.gray@realvnc.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

* 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6:
  Fix common misspellings

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: rpckbd - fix a leak of the IRQ during init failure
  Input: wacom - add support for Lenovo tablet ID (0xE6)
  Input: i8042 - downgrade selftest error message to dbg()
  Input: synaptics - fix crash in synaptics_module_init()
  Input: spear-keyboard - fix inverted condition in interrupt handler
  Input: uinput - allow for 0/0 min/max on absolute axes.
  Input: sparse-keymap - report KEY_UNKNOWN for unknown scan codes
  Input: sparse-keymap - report scancodes with key events
  Input: h3600_ts_input - fix a spelling error
  Input: wacom - report resolution for pen devices
  Input: wacom - constify wacom_features for a new missed Bamboo models

In rpckbd_open prror path, free_irq() was using NULL rather than the
driver data as the data pointer so free_irq() wouldn't have matched.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

On a "really fragile" laptop I noticed a single
    i8042.c: i8042 controller selftest failed. (0x1 != 0x55)

error in the log. But there's no reason to print this message at
KERN_ERR level each time that loop fails, especially since the message
telling about the overall selftest failure is printed at KERN_INFO level
(on X86).

Add an actual error message for non-X86 systems, where a selftest
failure is (apparently) more serious. Remove a space in an another error
message.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

Scripted with coccinelle.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

* 'defcfg' of master.kernel.org:/home/rmk/linux-2.6-arm:
  ARM: 6647/1: add Versatile Express defconfig
  ARM: 6644/1: mach-ux500: update the U8500 defconfig

* 'drivers' of master.kernel.org:/home/rmk/linux-2.6-arm:
  ARM: 6764/1: pl011: factor out FIFO to TTY code
  ARM: 6763/1: pl011: add optional RX DMA to PL011 v2
  ARM: 6758/1: amba: support pm ops
  ARM: amba: make amba_driver id_table const
  ARM: amba: make internal ID table handling const
  ARM: amba: make probe() functions take const id tables
  ARM: 6662/1: amba: make amba_bustype non-static
  ARM: mmci: add dmaengine-based DMA support
  ARM: mmci: no need for separate host->data_xfered
  ARM: mmci: avoid unnecessary switch to data available PIO interrupts
  ARM: mmci: no need to call flush_dcache_page() with sg_miter API
  ARM: mmci: avoid reporting too many completed bytes on fifo overrun
  ALSA: AACI: make fifo variables more explanitory
  ALSA: AACI: no need to call snd_pcm_period_elapsed() for each period
  ALSA: AACI: use snd_pcm_lib_period_bytes()
  ALSA: AACI: clean up AACI announcement printk
  ALSA: AACI: fix channel mask selection
  ALSA: AACI: fix number of channels for record
  ALSA: AACI: fix multiple IRQ claiming

* 'cyberpro-next' of master.kernel.org:/home/rmk/linux-2.6-arm:
  VIDEO: cyberpro: remove unused cyber2000fb_get_fb_var()
  VIDEO: cyberpro: remove useless function extreg pointers
  VIDEO: cyberpro: update handling of device structures
  VIDEO: cyberpro: add support for video capture I2C
  VIDEO: cyberpro: make 'reg_b0_lock' always present
  VIDEO: cyberpro: add I2C support
  VIDEO: cyberpro: select lowest multipler/divisor for PLL