linux-toradex.git/drivers/tty, branch v3.1.1

jsm: remove buggy write queue

2011-11-11T17:43:38+00:00

commit 9d898966c4a07e4a5092215b5a2829d0ef02baa2 upstream.

jsm uses a write queue that copies from uart_core circular buffer. This
copying however has some bugs, like not wrapping the head counter. Since
this write queue is also a circular buffer, the consumer function is
ready to use the uart_core circular buffer directly.

This buggy copying function was making some bytes be dropped when
transmitting to a raw tty, doing something like this.

[root@hostname ~]$ cat /dev/ttyn1 > cascardo/dump &
[1] 2658
[root@hostname ~]$ cat /proc/tty/drivers > /dev/ttyn0
[root@hostname ~]$ cat /proc/tty/drivers
/dev/tty             /dev/tty        5       0 system:/dev/tty
/dev/console         /dev/console    5       1 system:console
/dev/ptmx            /dev/ptmx       5       2 system
/dev/vc/0            /dev/vc/0       4       0 system:vtmaster
jsm                  /dev/ttyn     250 0-31 serial
serial               /dev/ttyS       4 64-95 serial
hvc                  /dev/hvc      229 0-7 system
pty_slave            /dev/pts      136 0-1048575 pty:slave
pty_master           /dev/ptm      128 0-1048575 pty:master
unknown              /dev/tty        4 1-63 console
[root@hostname ~]$ cat cascardo/dump
/dev/tty             /dev/tty        5       0 system:/dev/tty
/dev/console         /dev/console    5       1 system:console
/dev/ptmx            /dev/ptmx       5       2 system
/dev/vc/0            /dev/vc/0       4       0 system:vtmaste[root@hostname ~]$

This patch drops the driver write queue entirely, using the circular
buffer from uart_core only.

Signed-off-by: Thadeu Lima de Souza Cascardo 
Signed-off-by: Greg Kroah-Hartman

serial-core: power up uart port early before we do set_termios when resuming

2011-11-11T17:42:18+00:00

commit 94abc56f4d90f289ea32a0a11d3577fcd8cb28fb upstream.

The following patch removed uart_change_pm() in uart_resume_port():

commit 5933a161abcb8d83a2c145177f48027c3c0a8995
Author: Yin Kangkai 
    serial-core: reset the console speed on resume

It will break the pxa serial driver when the system resumes from suspend mode
as it will try to set baud rate divider register in set_termios but with
clock off. The register value can not be set correctly on some platform if
the clock is disabled. The pxa driver will check the value and report the
following warning:

------------[ cut here ]------------
WARNING: at drivers/tty/serial/pxa.c:545 serial_pxa_set_termios+0x1dc/0x250()
Modules linked in:
[] (unwind_backtrace+0x0/0xf0) from [] (warn_slowpath_common+0x4c/0x64)
[] (warn_slowpath_common+0x4c/0x64) from [] (warn_slowpath_null+0x18/0x1c)
[] (warn_slowpath_null+0x18/0x1c) from [] (serial_pxa_set_termios+0x1dc/0x250)
[] (serial_pxa_set_termios+0x1dc/0x250) from [] (uart_resume_port+0x128/0x2dc)
[] (uart_resume_port+0x128/0x2dc) from [] (serial_pxa_resume+0x18/0x24)
[] (serial_pxa_resume+0x18/0x24) from [] (platform_pm_resume+0x40/0x4c)
[] (platform_pm_resume+0x40/0x4c) from [] (pm_op+0x68/0xb4)
[] (pm_op+0x68/0xb4) from [] (device_resume+0xb0/0xec)
[] (device_resume+0xb0/0xec) from [] (dpm_resume+0xe0/0x194)
[] (dpm_resume+0xe0/0x194) from [] (dpm_resume_end+0xc/0x18)
[] (dpm_resume_end+0xc/0x18) from [] (suspend_devices_and_enter+0x16c/0x1ac)
[] (suspend_devices_and_enter+0x16c/0x1ac) from [] (enter_state+0xac/0xdc)
[] (enter_state+0xac/0xdc) from [] (state_store+0xa0/0xbc)
[] (state_store+0xa0/0xbc) from [] (kobj_attr_store+0x18/0x1c)
[] (kobj_attr_store+0x18/0x1c) from [] (sysfs_write_file+0x108/0x140)
[] (sysfs_write_file+0x108/0x140) from [] (vfs_write+0xac/0x134)
[] (vfs_write+0xac/0x134) from [] (sys_write+0x3c/0x68)
[] (sys_write+0x3c/0x68) from [] (ret_fast_syscall+0x0/0x2c)
---[ end trace 88289eceb4675b04 ]---

This patch fix the problem by adding the power on opertion back for uart
console when console_suspend_enabled is true.

Signed-off-by: Ning Jiang 
Tested-by: Mayank Rana 
Signed-off-by: Greg Kroah-Hartman

serial: pxa: work around for errata #20

2011-11-11T17:42:18+00:00

commit e44aabd649c80e8be16ede3ed3cbff6fb2561ca9 upstream.

Errata E20: UART: Character Timeout interrupt remains set under certain
software conditions.

Implication: The software servicing the UART can be trapped in an infinite loop.

Signed-off-by: Marcus Folkesson 
Signed-off-by: Greg Kroah-Hartman

TTY: pty, release tty in all ptmx_open fail paths

2011-11-11T17:42:12+00:00

commit 1177c0efc04d032644895b8d757f55b433912596 upstream.

Mistakenly, commit 64ba3dc3143d (tty: never hold BTM while getting
tty_mutex) switched one fail path in ptmx_open to not free the newly
allocated tty.

Fix that by jumping to the appropriate place. And rename the labels so
that it's clear what is going on there.

Introduced-in: v2.6.36-rc2
Signed-off-by: Jiri Slaby 
Cc: Arnd Bergmann 
Cc: Alan Cox 
Signed-off-by: Greg Kroah-Hartman

TTY: make tty_add_file non-failing

2011-11-11T17:42:12+00:00

commit fa90e1c935472281de314e6d7c9a37db9cbc2e4e upstream.

If tty_add_file fails at the point it is now, we have to revert all
the changes we did to the tty. It means either decrease all refcounts
if this was a tty reopen or delete the tty if it was newly allocated.

There was a try to fix this in v3.0-rc2 using tty_release in 0259894c7
(TTY: fix fail path in tty_open). But instead it introduced a NULL
dereference. It's because tty_release dereferences
filp->private_data, but that one is set even in our tty_add_file. And
when tty_add_file fails, it's still NULL/garbage. Hence tty_release
cannot be called there.

To circumvent the original leak (and the current NULL deref) we split
tty_add_file into two functions, making the latter non-failing. In
that case we may do the former early in open, where handling failures
is easy. The latter stays as it is now. So there is no change in
functionality.

The original bug (leak) was introduced by f573bd176 (tty: Remove
__GFP_NOFAIL from tty_add_file()). Thanks Dan for reporting this.

Later, we may split tty_release into more functions and call only some
of them in this fail path instead. (If at all possible.)

Introduced-in: v2.6.37-rc2
Signed-off-by: Jiri Slaby 
Reported-by: Dan Carpenter 
Cc: Alan Cox 
Cc: Pekka Enberg 
Signed-off-by: Greg Kroah-Hartman

TTY: drop driver reference in tty_open fail path

2011-11-11T17:42:11+00:00

commit c290f8358acaeffd8e0c551ddcc24d1206143376 upstream.

When tty_driver_lookup_tty fails in tty_open, we forget to drop a
reference to the tty driver. This was added by commit 4a2b5fddd5 (Move
tty lookup/reopen to caller).

Fix that by adding tty_driver_kref_put to the fail path.

I will refactor the code later. This is for the ease of backporting to
stable.

Introduced-in: v2.6.28-rc2
Signed-off-by: Jiri Slaby 
Cc: Alan Cox 
Acked-by: Sukadev Bhattiprolu 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus

2011-10-10T02:39:03+00:00

* 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus: (29 commits)
  MIPS: Call oops_enter, oops_exit in die
  staging/octeon: Software should check the checksum of no tcp/udp packets
  MIPS: Octeon: Enable C0_UserLocal probing.
  MIPS: No branches in delay slots for huge pages in handle_tlbl
  MIPS: Don't clobber CP0_STATUS value for CONFIG_MIPS_MT_SMTC
  MIPS: Octeon: Select CONFIG_HOLES_IN_ZONE
  MIPS: PM: Use struct syscore_ops instead of sysdevs for PM (v2)
  MIPS: Compat: Use 32-bit wrapper for compat_sys_futex.
  MIPS: Do not use EXTRA_CFLAGS
  MIPS: Alchemy: DB1200: Disable cascade IRQ in handler
  SERIAL: Lantiq: Set timeout in uart_port
  MIPS: Lantiq: Fix setting the PCI bus speed on AR9
  MIPS: Lantiq: Fix external interrupt sources
  MIPS: tlbex: Fix build error in R3000 code.
  MIPS: Alchemy: Include Au1100 in PM code.
  MIPS: Alchemy: Fix typo in MAC0 registration
  MIPS: MSP71xx: Fix build error.
  MIPS: Handle __put_user() sleeping.
  MIPS: Allow forced irq threading
  MIPS: i8259: Mark cascade interrupt non-threaded
  ...

SERIAL: Lantiq: Set timeout in uart_port

2011-09-21T15:53:25+00:00

Without this patch apps using readline hang.

Signed-off-by: Thomas Langer 
Signed-off-by: John Crispin 
Cc: linux-mips@linux-mips.org
Cc: linux-serial@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/2687/
Signed-off-by: Alan Cox 
Signed-off-by: Ralf Baechle

cris: fix a build error in drivers/tty/serial/crisv10.c

2011-09-15T01:09:38+00:00

Fix these errors:

    drivers/tty/serial/crisv10.c:4453: error: 'if_ser0' undeclared (first use in this function): 2 errors in 2 logs
    drivers/tty/serial/crisv10.c:4453: error: (Each undeclared identifier is reported only once: 2 errors in 2 logs
    drivers/tty/serial/crisv10.c:4453: error: for each function it appears in.): 2 errors in 2 logs

"if_ser0" is a typo, it should be "if_serial_0".

Signed-off-by: WANG Cong 
Cc: Mikael Starvik 
Cc: Jesper Nilsson 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-3.x

2011-08-29T20:34:48+00:00

* 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-3.x:
  sh: fix the compile error in setup-sh7757.c
  serial: sh-sci: report CTS as active for get_mctrl
  sh: Add unaligned memory access for PC relative intructions
  sh: Fix unaligned memory access for branches without delay slots
  sh: Fix up fallout from cpuidle changes.
  serial: sh-sci: console Runtime PM support
  sh: Fix conflicting definitions of ptrace_triggered
  serial: sh-sci: fix DMA build by including dma-mapping.h
  serial: sh-sci: Fix up default regtype probing.
  sh: intc: enable both edges GPIO interrupts on sh7372
  shwdt: fix usage of mod_timer
  clocksource: sh_cmt: wait for CMCNT on init V2