When DMA is enabled (with hardware flow control enabled) the FIFO size
must be set to the size of the DMA buffer, as this is the size the tty
subsystem can use.
Signed-off-by: Hector Palacios <hector.palacios@digi.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit d0380e6c3c0f6edb986d8798a23acfaf33d5df23 (early_printk:
consolidate random copies of identical code) added in 3.10 introduced
a check for con->index == -1 in early_console_register().
Initialize index to -1 for the xenboot console so earlyprintk=xen
works again.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Driver core clears the driver data to NULL after device_release
or on probe failure, so just remove it from here.
Driver core change:
"device-core: Ensure drvdata = NULL when no driver is bound"
(sha1: 0998d0631001288a5974afc0b2a5f568bcdecb4d)
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When configured with UART_16550_COMPATIBLE=NO or in versions prior to
the introduction of this option, the Designware UART will ignore writes
to the LCR if the UART is busy. The current workaround saves a copy of
the last written LCR and re-writes it in the ISR for a special interrupt
that is raised when a write was ignored.
Unfortunately, interrupts are typically disabled prior to performing a
sequence of register writes that include the LCR so the point at which
the retry occurs is too late. An example is serial8250_do_set_termios()
where an ignored LCR write results in the baud divisor not being set and
instead a garbage character is sent out the transmitter.
Furthermore, since serial_port_out() offers no way to indicate failure,
a serious effort must be made to ensure that the LCR is actually updated
before returning back to the caller. This is difficult, however, as a
UART that was busy during the first attempt is likely to still be busy
when a subsequent attempt is made unless some extra action is taken.
This updated workaround reads back the LCR after each write to confirm
that the new value was accepted by the hardware. Should the hardware
ignore a write, the TX/RX FIFOs are cleared and the receive buffer read
before attempting to rewrite the LCR out of the hope that doing so will
force the UART into an idle state. While this may seem unnecessarily
aggressive, writes to the LCR are used to change the baud rate, parity,
stop bit, or data length so the data that may be lost is likely not
important. Admittedly, this is far from ideal but it seems to be the
best that can be done given the hardware limitations.
Lastly, the revised workaround doesn't touch the LCR in the ISR, so it
avoids the possibility of a "serial8250: too much work for irq" lock up.
This problem is rare in real situations but can be reproduced easily by
wiring up two UARTs and running the following commands.
# stty -F /dev/ttyS1 echo
# stty -F /dev/ttyS2 echo
# cat /dev/ttyS1 &
[1] 375
# echo asdf > /dev/ttyS1
asdf
[ 27.700000] serial8250: too much work for irq96
[ 27.700000] serial8250: too much work for irq96
[ 27.710000] serial8250: too much work for irq96
[ 27.710000] serial8250: too much work for irq96
[ 27.720000] serial8250: too much work for irq96
[ 27.720000] serial8250: too much work for irq96
[ 27.730000] serial8250: too much work for irq96
[ 27.730000] serial8250: too much work for irq96
[ 27.740000] serial8250: too much work for irq96
Signed-off-by: Tim Kryger <tim.kryger@linaro.org>
Reviewed-by: Matt Porter <matt.porter@linaro.org>
Reviewed-by: Markus Mayer <markus.mayer@linaro.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move the printk() calls to to dev_*() instead, to tie into the dynamic
debugging infrastructure.
Also change some "raw" printk() calls to dev_err() to provide a better
error message to userspace so it can properly identify the device and
not just have to guess.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
__initdata tag should be placed between the variable name and equal
sign for the variable to be placed in the intended .init.data section.
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit f95499c3030fe1bfad57745f2db1959c5b43dca8,
n_tty: Don't wait for buffer work in read() loop
creates a race window which can cause a pty master read()
to miss the last pty slave write(s) and return -EIO instead,
thus signalling the pty slave is closed. This can happen when
the pty slave is written and immediately closed but before the
tty buffer i/o loop receives the new input; the pty master
read() is scheduled, sees its read buffer is empty and the
pty slave has been closed, and exits.
Because tty_flush_to_ldisc() has significant performance impact
for parallel i/o, rather than revert the commit, special case this
condition (ie., when the read buffer is empty and the 'other' pty
has been closed) and, only then, wait for buffer work to complete
before re-testing if the read buffer is still empty.
As before, subsequent pty master reads return any available data
until no more data is available, and then returns -EIO to
indicate the pty slave has closed.
Reported-by: Mikael Pettersson <mikpelinux@gmail.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Mikael Pettersson <mikpelinux@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The xen_raw_printk works great for debugging purposes. We use
for PV guests and we can also use it for HVM guests.
However, for HVM guests we have a fallback of using the 0xe9
port in case the hypervisor does not support an HVM guest of
using the console_io hypercall. As such lets use 0xe9 during
early bootup, and once the hyper-page is setup and if the
console_io hypercall is supported - use that. Otherwise we
will fallback to using the 0xe9 after early bootup.
We also alter the return value for dom0_write_console to return
an error value instead of zero. The HVC API has been supporting
returning error values for quite some time.
P.S.
To use (and to see the output in the Xen ring buffer) one has to build
the hypervisor with 'debug=y'.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v1: ifdef xen_cpuid_base as it is X86 specific]
Here are some serial at tty driver fixes for 3.12-rc3
The serial driver fixes some kref leaks, documentation is moved to the proper
places, and the tty and n_tty fixes resolve some reported regressions. There
is still one outstanding tty regression fix that isn't in here yet, as I want
to test it out some more, it will be sent for 3.12-rc4 if it checks out.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are some serial at tty driver fixes for 3.12-rc3
The serial driver fixes some kref leaks, documentation is moved to the
proper places, and the tty and n_tty fixes resolve some reported
regressions. There is still one outstanding tty regression fix that
isn't in here yet, as I want to test it out some more, it will be sent
for 3.12-rc4 if it checks out"
* tag 'tty-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: ar933x_uart: move devicetree binding documentation
tty: Fix SIGTTOU not sent with tcflush()
n_tty: Fix EOF push index when termios changes
serial: pch_uart: remove unnecessary tty_port_tty_get
serial: pch_uart: fix tty-kref leak in dma-rx path
serial: pch_uart: fix tty-kref leak in rx-error path
serial: tegra: fix tty-kref leak
The stub for dw8250_probe_acpi() is missing an argument.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Intel BayTrail has two HS-UARTs with 64 byte fifo, support
for DMA and support for 16750 compatible Auto Flow Control.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is not a bug on our side, but a misdesign in ITU T.416, yet with
all popular terminals supporting these codes, people consider this to
be a bug in Linux. By breaking the design principles behind SGR codes
(gracefully ignoring unsupported ones should not require knowing about
them), 256 colour ones tend to turn blinking on before invoking an
arbitrary unrelated command.
This commit doesn't add such support, merely skips such codes without
ill effects.
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
No modern terminal supports them, and SGR 38 conflicts with detecting
xterm-256 colours. This also makes SGR 39 consistent with other popular
terminals. Neither are used by ncurses' terminfo.
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The original version of this was done by Bastian Blank, who wrote:
> The problem is the following:
> - Architecture specific code sets preferred console to something bogus.
> - Command line handling tries to set preferred console but is overruled
> by the old setting.
>
> The udbg0 console is a boot console and independant.
References: http://bugs.debian.org/492703
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The nice thing about devm_* is that the driver doesn't need to free the
resources but the driver core takes care about that.
These calls were introduced in commit c08f015 (serial: clps711x: Using
CPU clock subsystem for getting base UART speed).
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add the missing uart_unregister_driver() before return
from sccnxp_probe() in the error handling case.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make Mode16 more preferred than Mode13, to match TRM baudrates table.
Signed-off-by: Alexey Pelykh <alexey.pelykh@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In rx timeout ISR and tasklet, we don't issue new dma desc as rx_done ISR
will do that.
Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This resolves a warning where resource_size_t is larger than void *:
drivers/tty/serial/imx.c:1542:6: warning: cast to pointer from integer
of different size [-Wint-to-pointer-cast]
Since iomem_base is a void *, casting to unsigned long is safe.
It's unclear to me that this comparison is truly needed, but it's there
on several other drivers as well.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Samsung serial driver currently does not support setting the
RTS pin with an ioctl(TIOCMSET) call. This patch adds this support.
Changes in v2:
- Preserve the RTS pin's manual setting in set_termios() also when
enabling CRTSCTS.
Signed-off-by: José Miguel Gonçalves <jose.goncalves@inov.pt>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The channel IDs are set to -1 by default. It will prevent
dmaengine from trying to provide the first free channel if
it fails to allocate exclusive channel. This will fix an
issue with ACPI enumerated UARTs that do not support DMA
but still end up getting a DMA channel incorrectly.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It should be available for DT users as well. This does not
enable DMA by default except with ACPI. DT users can enable
DMA based on a property.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
DMA engines usually expect the fifo trigger level to be
aligned with the burst size. It should not be changed even
with small baud rates. This will fix an issue with
Designware DMA engine where the data can not be transferred
over UART with lower baud rates then 2400.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pch_uart currently isn't auto-loaded if built as a module.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a PCI driver and should be auto-loaded based on PCI ID.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Kconfig for this option suggests it's only relevant on STi SoCs,
so add depends to have it not show up on archs that won't ever run it.
Signed-off-by: Dave Jones <davej@fedoraproject.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit f7d2c0bbd (serial: i.MX: evaluate linux,stdout-path property) introduced
the following sparse warning:
drivers/tty/serial/imx.c:1916:77: warning: Using plain integer as NULL pointer
Pass NULL as the last argument of add_preferred_console() instead of zero.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Enabling the ARM DCC console and using without a JTAG connection will
simply hang the system. Since distros like to turn on all options, this
is a reoccurring problem to debug. We can do better by checking if
anything is attached and handling characters. There is no way to probe
this, so send a newline and check that it is handled.
Cc: Paolo Pisati <paolo.pisati@canonical.com>
Cc: Tim Gardner <tim.gardner@canonical.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Although originally conceived as a hook for port drivers to know
when a port reference is dropped, no driver uses this method.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the tty driver mistakenly drops the last port reference
before the tty has been released, issue a diagnostic and
abort the port destruction.
This will leak memory and may zombify the port, but might
otherwise keep the machine in runnable state.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove braces from single-statement conditional in
n_tty_set_termios.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 'e7f3880cd9b98c5bf9391ae7acdec82b75403776'
tty: Fix recursive deadlock in tty_perform_flush()
introduced a regression where tcflush() does not generate
SIGTTOU for background process groups.
Make sure ioctl(TCFLSH) calls tty_check_change() when
invoked from the line discipline.
Cc: stable@vger.kernel.org # v3.10+
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Starting from v3.10 (probably commit f91e2590410b: "tty: Signal
foreground group processes in hangup") disassociate_ctty() sends SIGCONT
if tty && on_exit. This breaks LSB test-suite, in particular test8 in
_exit.c and test40 in sigcon5.c.
Put the "!on_exit" check back to restore the old behaviour.
Review by Peter Hurley:
"Yes, this regression was introduced by me in that commit. The effect
of the regression is that ptys will receive a SIGCONT when, in similar
circumstances, ttys would not.
The fact that two test vectors accidentally tripped over this
regression suggests that some other apps may as well.
Thanks for catching this"
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Karel Srot <ksrot@redhat.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 40d5e0905a03601d40cd4e46b8690093c2355d03,
'n_tty: Fix EOF push handling' introduced a subtle state
change error wrt EOF push handling when the termios is
changed from non-canonical to canonical mode.
Reset line_start to the current read_tail index, not 0.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove unused tty-reference from dma-rx path which was left after the
recent tty-port conversions.
Also remove a redundant port initialisation while at it.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix tty_kref leak when tty_buffer_request room fails in dma-rx path.
Note that the tty ref isn't really needed anymore, but as the leak has
always been there, fixing it before removing should makes it easier to
backport the fix.
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
