* do not test if tty->index is in bounds. It is always.
* tty->index is not a minor! Fix that.
>From now on, let's assume that the parameter of the function is tty
index with base being zero. This makes also the code more readable.
Factually, there is no real change as tty_driver->minor_start is zero,
so the tests are equivalent. But it did not make sense. And if this
had changed eventually, it would have caused troubles.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Checking if tty->index is in bounds is not needed. The tty has the
index set in the initial open. This is done in get_tty_driver. And it
can be only in interval <0,driver->num).
So remove the tests which check exactly this interval. Some are
left untouched as they check against the current backing device count.
(Leaving apart that the check is racy in most of the cases.)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is from tty_reopen:
struct tty_driver *driver = tty->driver;
...
tty->driver = driver;
and it doesn't make sense at all. The driver is intended to be set in
initialize_tty_struct from tty_init_dev (initial open). So this set in
tty_reopen is not needed.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove the useless local variable and return the value itself.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All num, magic and owner are set by alloc_tty_driver. No need to
re-set them on each allocation site.
pti driver sets something different to what it passes to
alloc_tty_driver. It is not a bug, since we don't use the lines
parameter in any way. Anyway this is fixed, and now we do the right
thing.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Like the rest of the kernel, make a stub from alloc_tty_driver which
calls __alloc_tty_driver with proper owner. This will save us one more
assignment on the driver side.
Also this fixes some drivers which didn't set the owner. This allowed
user to remove the module from the system even though a tty from the
driver is still open.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
TTY buffer head and tail are initialized in tty_buffer_init. No need
to do it once again in initialize_tty_struct where tty_buffer_init is
called.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We leave the existing paste mess alone and just fix up the vt side of
things.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some of this ventures into selection which is still a complete lost cause. We
are not making it any worse. It's completely busted anyway.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At this point we have the tty_lock guarding a couple of oddities, plus the
translation and unimap still.
We also extend the console_lock in a couple of spots where coverage is wrong
and switch vcs_open to use the right lock !
[Fixed the locking issue Jiri reported]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The font methods are console_lock covered. Unfortunately they don't extend
the lock over all the needed tests.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
TIOCSERGETLSR should be saved in a uint so the cast here to unsigned
long is a bug.
Reported-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The following commit: be4b028195
(tty: serial: OMAP: block idle while the UART is transferring data in PIO mode),
is introducing an oops if OMAP is booted using device tree blob because
the pdata will not be initialized.
Check if pdata is set before de-referencing it.
Signed-off-by: Benoit Cousson <b-cousson@ti.com>
Reviewed-by: Paul Walmsley <paul@pwsan.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Keyboard struct lifetime is easy, but the locking is not and is completely
ignored by the existing code. Tackle this one head on
- Make the kbd_table private so we can run down all direct users
- Hoick the relevant ioctl handlers into the keyboard layer
- Lock them with the keyboard lock so they don't change mid keypress
- Add helpers for things like console stop/start so we isolate the poking
around properly
- Tweak the braille console so it still builds
There are a couple of FIXME locking cases left for ioctls that are so hideous
they should be addressed in a later patch. After this patch the kbd_table is
private and all the keyboard jiggery pokery is in one place.
This update fixes speakup and also a memory leak in the original.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
First step to debletcherising the vt console layer - pick a victim and fix
the locking
This is a nice simple object with its own rules so lets pick it out for
treatment. The user of the table already has a lock so we will also use the
same lock for updates.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit a50f724a43.
Sasha reported that this causes problems, so revert it.
Cc: Alan Cox <alan@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit d3bda5298a.
Sasha reported that this causes problems, so revert it.
Cc: Sasha Levin <levinsasha928@gmail.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In DMA-operated uart, I found that rx data can be taken by the UART
interrupts during the DMA irq handler. pl011_int is occurred just
before it goes inside spin_lock_irq. When it returns to the callback,
DMA buffer already has been flushed. Then, pl011_dma_rx_chars gets
invalid data. So I add check for the residue as the patch bellow.
Signed-off-by: Chanho Min <chanho.min@lge.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Without that fix machines having a s3c2442 CPU have something
like that in dmesg:
samsung-uart s3c2440-uart.0: could not find driver data
samsung-uart s3c2440-uart.1: could not find driver data
samsung-uart s3c2440-uart.2: could not find driver data
And serial is never initialized.
The previous log was obtained trough early printk on the gta02
machine.
Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@no-log.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/serial/mux.c included 'linux/tty.h' twice, remove
the duplicate.
Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are multiple users of this file from different source
paths now, and rather than have ../ paths in include statements,
just move the file to the linux header dir.
Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The receive FIFO wakeup latency estimate in the omap-serial driver is
three orders of magnitude too small. This effectively prevents the
MPU from going to a low-power state when CONFIG_CPU_IDLE=y. This is a
major power management regression and masks some other FIFO-related
bugs in the driver.
Fix by correcting the most egregious problem in the RX wakeup latency
estimate. There are several other flaws in the estimator; these will
be fixed by a separate patch series intended for 3.4.
The difference in low-power states with this patch can be observed via
debugfs in pm_debug/count.
This estimate does not have any effect when CONFIG_CPU_IDLE=n.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: Govindraj.R <govindraj.raja@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Prevent OMAP UARTs from going idle while they are still transferring
data in PIO mode. This works around an oversight in the OMAP UART
hardware present in OMAP34xx and earlier: an idle UART won't send a
wakeup when the TX FIFO threshold is reached. This causes long delays
during data transmission when the MPU powerdomain enters a low-power
mode. The MPU interrupt controller is not able to respond to
interrupts when it's in a low-power state, so the TX buffer is not
refilled until another wakeup event occurs.
This fix changes the erratum i291 DMA idle workaround. Rather than
toggling between force-idle and no-idle, it will toggle between
smart-idle and no-idle. The important part of the workaround is the
no-idle part, so this shouldn't result in any change in behavior.
This fix should work on all OMAP UARTs. Future patches intended for
the 3.4 merge window will make this workaround conditional on a
"feature" flag, and will use the OMAP36xx+ TX event wakeup support.
Thanks to Kevin Hilman <khilman@ti.com> for mentioning the erratum i291
workaround, which led to the development of this approach.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Govindraj.R <govindraj.raja@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the (default) PIO mode, use a one-byte RX FIFO threshold. The OMAP
UART IP blocks do not appear to be capable of waking the system under
an RX timeout condition. Since the previous RX FIFO threshold was 16
bytes, this meant that omap-serial.c did not become aware of any
received data until all those bytes arrived or until another UART
interrupt occurred. This made the serial console and presumably other
serial applications (GPS, serial Bluetooth) unusable or extremely
slow. A 1-byte RX FIFO threshold also allows the MPU to enter a
low-power consumption state while waiting for the FIFO to fill.
This can be verified using the serial console by comparing the
behavior when "0123456789abcde" is pasted in from another window, with
the behavior when "0123456789abcdef" is pasted in. Since the former
string is less than sixteen bytes long, the string is not echoed for
some time, while the latter string is echoed immediately.
DMA operation is unaffected by this patch.
Thanks to Russell King - ARM Linux <linux@arm.linux.org.uk> for some
additional information on the standard behavior of the RX timeout
event, which was used to improve this commit description.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Govindraj Raja <govindraj.r@ti.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This allows altera_uart to be used for KGDB debugging over serial line.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function has no users inside the tree and the nios2
(out-of-mainline) port doesn't use it either (anymore).
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There's a real possibility of killing kernel threads that might
have issued use_mm(), so kthread's mm might become non-NULL.
This patch fixes the issue by checking for PF_KTHREAD (just as
get_task_mm()).
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sysrq should grab the tasklist lock, otherwise calling force_sig() is
not safe, as it might race with exiting task, which ->sighand might be
set to NULL already.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pch_uart_hal_request() has parameters which it never uses, also
it is very short, so merge it with its caller to make code cleaner.
No functional changes at all.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The short get_msr() has some unnecessary code and only used once,
so merge it with its caller to make code cleaner. No functional
change at all.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This driver will be use as interfaces for multiple kinds of
devices like Bluetooth/GPS etc, this debug hook will make driver
debugging much easier.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 9bef3d4197
"serial: group all the 8250 related code together"
inadvertently swept up the m32r driver in the move, because
it had comments mentioning 8250 registers within it. However
these are only there by nature of the driver being based off
the 8250 source code -- the hardware itself does not actually
have any relation to the original 8250 style UARTs.
Reported-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On sparc, there is a build failure:
drivers/tty/serial/8250/8250.c:48:21: error: suncore.h: No such file or directory
drivers/tty/serial/8250/8250.c:3275: error: implicit declaration of function 'sunserial_register_minors'
drivers/tty/serial/8250/8250.c:3305: error: implicit declaration of function 'sunserial_unregister_minors'
this is due to commit 9bef3d4197
(serial: group all the 8250 related code together) moved these files
into 8250/ subdirectory, but forgot to change the reference
to drivers/tty/serial/suncore.h.
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This should be added for EXYNOS4212 and EXYNOS4412 SoCs.
Cc: Thomas Abraham <thomas.abraham@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
KDFONTOP(GET) currently fails with EIO when being run in a 32bit userland
with a 64bit kernel if the font width is not 8.
This is because the compatibility layer introduced by e9216651 ("tty:
handle VT specific compat ioctls in vt driver") forces the addition of the
KD_FONT_FLAG_OLD flag, which makes con_font_get return EIO in such case.
This flag should *not* be set for KDFONTOP, since it's actually the whole
point of this flag (see comment in con_font_set for instance).
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Arthur Taylor <art@ified.ca>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
devpts operations are protected by inode mutexes and dentry
refcounting. There is no need to hold BTM.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code looks like:
if (tty->driver->subtype == PTY_TYPE_MASTER) {
...
if (tty->driver == ptm_driver)
But the second if is superfluous because only the ptm_driver is of
PTY_TYPE_MASTER subtype.
Also we can remove the #if now because devpts_pty_kill is defined as
an empty function for non-CONFIG_UNIX98_PTYS configs.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the helper in the rest of the tty drivers. This is a simple
replacement.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are currently many cut&paste copies of what
tty_driver_install_tty does when custom ->install method is not
provided. Let's get rid of the copies and create a helper with this
setup code.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Havard Skinnemoen <hskinnemoen@google.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The receive FIFO wakeup latency estimate in the omap-serial driver is
three orders of magnitude too small. This effectively prevents the
MPU from going to a low-power state when CONFIG_CPU_IDLE=y. This is a
major power management regression and masks some other FIFO-related
bugs in the driver.
Fix by correcting the most egregious problem in the RX wakeup latency
estimate. There are several other flaws in the estimator; these will
be fixed by a separate patch series intended for 3.4.
The difference in low-power states with this patch can be observed via
debugfs in pm_debug/count.
This estimate does not have any effect when CONFIG_CPU_IDLE=n.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: Govindraj.R <govindraj.raja@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Prevent OMAP UARTs from going idle while they are still transferring
data in PIO mode. This works around an oversight in the OMAP UART
hardware present in OMAP34xx and earlier: an idle UART won't send a
wakeup when the TX FIFO threshold is reached. This causes long delays
during data transmission when the MPU powerdomain enters a low-power
mode. The MPU interrupt controller is not able to respond to
interrupts when it's in a low-power state, so the TX buffer is not
refilled until another wakeup event occurs.
This fix changes the erratum i291 DMA idle workaround. Rather than
toggling between force-idle and no-idle, it will toggle between
smart-idle and no-idle. The important part of the workaround is the
no-idle part, so this shouldn't result in any change in behavior.
This fix should work on all OMAP UARTs. Future patches intended for
the 3.4 merge window will make this workaround conditional on a
"feature" flag, and will use the OMAP36xx+ TX event wakeup support.
Thanks to Kevin Hilman <khilman@ti.com> for mentioning the erratum i291
workaround, which led to the development of this approach.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Govindraj.R <govindraj.raja@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the (default) PIO mode, use a one-byte RX FIFO threshold. The OMAP
UART IP blocks do not appear to be capable of waking the system under
an RX timeout condition. Since the previous RX FIFO threshold was 16
bytes, this meant that omap-serial.c did not become aware of any
received data until all those bytes arrived or until another UART
interrupt occurred. This made the serial console and presumably other
serial applications (GPS, serial Bluetooth) unusable or extremely
slow. A 1-byte RX FIFO threshold also allows the MPU to enter a
low-power consumption state while waiting for the FIFO to fill.
This can be verified using the serial console by comparing the
behavior when "0123456789abcde" is pasted in from another window, with
the behavior when "0123456789abcdef" is pasted in. Since the former
string is less than sixteen bytes long, the string is not echoed for
some time, while the latter string is echoed immediately.
DMA operation is unaffected by this patch.
Thanks to Russell King - ARM Linux <linux@arm.linux.org.uk> for some
additional information on the standard behavior of the RX timeout
event, which was used to improve this commit description.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Govindraj Raja <govindraj.r@ti.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We transform the offenders into a test of irq <= 0 which will be ok while
the ARM people get their platform sorted. Once that is done (or in a while
if they don't do it anyway) then we will change them all to !irq checks.
For arch specific drivers that are already using NO_IRQ = 0 we just test
against zero so we don't need to re-review them later.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
