These methods are invoked if the iMX uart is used in conjuction with kgdb during
early boot. In order to access the UART without the interrupts, the kernel uses
the basic polling methods for IO with the device. With these methods
implemented, it is now possible to enable kgdb during early boot over serial.
Signed-off-by: Saleem Abdulrasool <compnerd@compnerd.org>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
CC: Sascha Hauer <s.hauer@pengutronix.de>
CC: Fabio Estevam <festevam@gmail.com>
CC: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
CC: linux-serial@vger.kernel.org
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Factor out the uart save/restore functionality instead of
having the same code several times in the driver.
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
CC: Saleem Abdulrasool <compnerd@compnerd.org>
CC: Sascha Hauer <s.hauer@pengutronix.de>
CC: Fabio Estevam <festevam@gmail.com>
CC: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
CC: linux-serial@vger.kernel.org
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When the uart device is instantiated by dt but dt doesn't provide an
alias then better let probing fail instead of falling back to an
unrelated device id used for the line number and no platform data.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
A quick look at of_alias_get_id shows that in the error case it returns
-ENODEV, too, but still it's better style to propagate the value as is.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>
Cc: Jason Liu <jason.hui@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Jason Liu <jason.hui@linaro.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Allow UART to be a source for wakeup from low power mode.
Tested on a MX27PDK by doing:
echo enabled > /sys/devices/platform/imx21-uart.0/tty/ttymxc0/power/wakeup
echo mem > /sys/power/state
and then pressing a key in the console will wakeup the sytem.
Suggested-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Tested-by: Richard Zhao <richard.zhao@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This driver was copied from the original 8250 driver and hence
got the DEC alpha errata workaround. But the workaround is ugly
and we don't really want it in any more places than it absolutely
needs to be. Obviously ARCH=m32r means ARCH != alpha, so just
remove the references to the ALPHA_KLUDGE_MCR define.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Patch to fix a spinlock lockup in the driver that sometimes happens when the
tasklet starts.
Signed-off-by: Claudio Scordino <claudio@evidence.eu.com>
Signed-off-by: Dave Bender <codehero@gmail.com>
Tested-by: Dave Bender <codehero@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
add support for 400Hv3, 410Hv3 and 800Hv3
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Blackfin uart supports automatic CTS trigger when hardware flow control is enabled.
No need to start and top tx in CTS interrupt. So, remote ASYNC_CTS_FLOW flag.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The recent commit "serial: add irq handler for Freescale 16550 errata"
would allow Kconfig choices that had 8250 support as a module and
yet still try and build in the errata fix non-modular, resulting
in build failures for some non-embedded PPC targets.
Since we hook in the errata fix from legacy_serial.c, which is
built only for PPC_UDBG_16550, and since the errata is only really
relevant for SysRQ on serial console, tighten up the dependencies
to be exactly that.
We'll get coverage on the relevant Freescale boards because the
Kconfig for their CPU types all select the PPC_UDBG_16550 option,
and the defconfigs also all select the 8250_CONSOLE option. Also,
the 8250_CONSOLE option has a strict dependency on "SERIAL_8250=y"
which resolves the reported problem for non Freescale targets.
Reported-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Tested-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Sending a break on the SOC UARTs found in some MPC83xx/85xx/86xx
chips seems to cause a short lived IRQ storm (/proc/interrupts
typically shows somewhere between 300 and 1500 events). Unfortunately
this renders SysRQ over the serial console completely inoperable.
The suggested workaround in the errata is to read the Rx register,
wait one character period, and then read the Rx register again.
We achieve this by tracking the old LSR value, and on the subsequent
interrupt event after a break, we don't read LSR, instead we just
read the RBR again and return immediately.
The "fsl,ns16550" is used in the compatible field of the serial
device to mark UARTs known to have this issue.
Thanks to Scott Wood for providing the errata data which led to
a much cleaner fix.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently serial8250_handle_irq is a trivial wrapper around
serial8250_handle_port, which actually does all the work.
Since there are no other callers of serial8250_handle_port, we
can just move it inline into serial8250_handle_irq. This also
makes it more clear what functionality any custom IRQ handlers
need to provide if not using serial8250_default_handle_irq.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The current 8250 timeout code duplicates the code path in
serial8250_default_handle_irq and then serial8250_handle_irq
i.e. reading iir, check for IIR_NO_INT, and then calling
serial8250_handle_port.
So the immediate thought is to replace the duplicated code
with a call to serial8250_default_handle_irq.
But this highlights a problem. We let 8250 driver variants
use their own IRQ handler via specifying their own custom
->handle_irq, but in the event of a timeout, we ignore their
handler and implicitly run serial8250_default_handle_irq instead.
So, go through the struct to get ->handle_irq and call that,
which for most will still be serial8250_default_handle_irq.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
For drivers that need to construct their own IRQ handler, the
three components are seen in the current handle_port -- i.e.
Rx, Tx and modem_status.
Make these exported symbols so that "almost" 8250 UARTs can
construct their own IRQ handler with these shared components,
while working around their own unique errata issues.
The function names are given a serial8250 prefix, since they
are now entering the global namespace.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The receive_chars() was taking a pointer to a passed in LSR value
in status and knocking off bits as it processed them. But since
receive_chars isn't returning a value, we can instead pass in
a normal non-pointer value for LSR, and simply return the
residual (unprocessed) LSR once it is done.
The value in this cleanup, is that it clarifies the API of the
receive_chars prior to exporting it to other 8250-like drivers
for shared usage.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Since we want to promote sharing and move away from one single
uart driver with a bunch of platform specific bugfixes all
munged into one, relocate some header like material from
the C file to the header.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
msm_hs_handle_delta_cts tries to acquire port->lock already acquired
by the callee function msm_hs_isr. Change function name to follow
"_locked" convention.
Signed-off-by: Mayank Rana <mrana@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Both tx and rx command_ptr_ptr are of type u32*. While allocating
memory for it, sizeof(u32 *) is used as part of kmalloc API instead
of sizeof(u32). ADM Hardare requires size of command_ptr_ptr as 1 Word.
Both sizeof(u32 *) and sizeof(u32) are same on 32-bit architecture
whereas sizeof(u32 *) would be different in size compare to sizeof(u32)
on anyother architecture.
Hence correct usage of sizeof(command_ptr_ptr) for Tx and Rx with
kmalloc and dma_(map/unmap)_single APIs.
Signed-off-by: Mayank Rana <mrana@codeaurora.org>
Reported-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Current serial_cs driver has a problem when trying to detect whether
a card has multiple ports: serial_config() calls pcmcia_loop_config()
which iterates over card CIS configurations by calling
serial_check_for_multi() for each of them.
This function wants to check (and select) a configuration
that has either one long I/O window spanning multiple ports or two 8-port
windows for two serial ports.
Problem is, that every pcmcia_loop_config() iteration only updates
the windows (via pcmcia_do_loop_config() in resource[0] and resource[1])
when CONF_AUTO_SET_IO flag is set on the device, which is set only later
in the code.
Fix it by setting this flag earlier.
In addition to this, when multi-port card is detected
and it does not have an one, long I/O window
multi_config_check_notpicky() tries to locate two I/O windows and assumes
they are continuous without checking.
On an Argosy RS-COM 2P this selects first configuration, which
unfortunately has two non-continuous I/O windows.
The net effect is that the second serial port on the card does not work.
Fix it by checking whether the windows are really continuous.
Signed-off-by: Maciej Szmigiero <mhej@o2.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Makes it easier to find all occurences requesting CONF_MODE_B.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch is similar to that for bfin-uart hardware flow control.
Sport emulated serial device may be probed earlier before GPIOLIB is initialized.
Requesting and configuring CTS GPIO PIN fails in that early stage.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Blackfin hardware CTS control generate interrupt for both CTS on and off.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Serial device may be probed earlier before GPIOLIB is initialized. Requesting and
configuring CTS GPIO PIN fails in that early stage. Do it when the serial device
really starts up.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
N_HDLC can spoil tty->flags because use not atomic operations on tty->flags.
I use n_hdlc line discipline and it happens.
Signed-off-by: Ilya Zykov <ilya@ilyx.ru>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch converts the drivers in drivers/tty/serial/* to use the
module_platform_driver() macro which makes the code smaller and a bit
simpler.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jamie Iles <jamie@jamieiles.com>
Cc: Yoichi Yuasa <yuasa@linux-mips.org>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In ancient times it was necessary to manually initialize the bus field of an
spi_driver to spi_bus_type. These days this is done in spi_driver_register(),
so we can drop the manual assignment.
The patch was generated using the following coccinelle semantic patch:
// <smpl>
@@
identifier _driver;
@@
struct spi_driver _driver = {
.driver = {
- .bus = &spi_bus_type,
},
};
// </smpl>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The semantics of UPF_IIR_ONCE (once per serial irq) are only guaranteed
if the kt irq is not shared (once per serial isr in the shared case ==
potentially unwanted reads of the IIR).
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Workaround dropped notifications in the iir register. Prevent reads
coincident with new interrupt notifications by reading the iir at most
once per interrupt.
Reported-by: Nhan H Mai <nhan.h.mai@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There is no need to call uart_write_wakeup after each character send.
Once at the end of the write sequence is enough.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The function check_modem_status returns an int currently it
is stored in a char.
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
TTY: ldisc, wait for ldisc infinitely in hangup
TTY: ldisc, move wait idle to caller
TTY: ldisc, allow waiting for ldisc arbitrarily long
Revert "tty/serial: Prevent drop of DCD on suspend for Tegra UARTs"
RS485: fix inconsistencies in the meaning of some variables
pch_uart: Fix DMA resource leak issue
serial,mfd: Fix CMSPAR setup
tty/serial: Prevent drop of DCD on suspend for Tegra UARTs
pch_uart: Change company name OKI SEMICONDUCTOR to LAPIS Semiconductor
pch_uart: Support new device LAPIS Semiconductor ML7831 IOH
pch_uart: Fix hw-flow control issue
tty: hvc_dcc: Fix duplicate character inputs
jsm: Change maintainership
SiRFprimaII is the latest generation application processor from CSR’s
multi-function SoC product family.
The SoC support codes are in arch/arm/mach-prima2 from Linux mainline
3.0.
There are three dedicated UARTs in system. This patch adds basic driver
support for them.
It has used the newest pinmux subsystem from Linus Walleij.
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rong Wang <Rong.Wang@csr.com>
Signed-off-by: Bin Shi <Bin.Shi@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
They were cut&pasted from tty_io. Many of them are not needed in
tty_ldisc.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Instead of the hackish way of counting ptys, let's define a specific
->remove hook both from slave and master. And decrease the count only
for master.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
For /dev/console case, we do not kill all ldisc users. It's due to
redirected_tty_write test in __tty_hangup. In that case there still
might be a process waiting e.g. in n_tty_read for input.
We wait for such processes to disappear. The problem is that we use a
timeout. After this timeout, we continue closing the ldisc and start
freeing tty resources. It obviously leads to crashes when the other
process is woken.
So to fix this, we wait infinitely before reiniting the ldisc. (The
tiocsetd remains untouched -- times out after 5s.)
This is nicely reproducible with this run from shell:
exec 0<>/dev/console 1<>/dev/console 2<>/dev/console
and stopping a getty like:
systemctl stop serial-getty@ttyS0.service
The crash proper may be produced only under load or with constified
timing the same as for 92f6fa09b.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Dave Young <hidave.darkstar@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Dmitriy Matrosov <sgf.dma@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It is the only place where reinit is called from. And we really need
to wait for the old ldisc to go once. Actually this is the place where
the waiting originally was (before removed and re-added later).
This will make the fix in the following patch easier to implement.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Dave Young <hidave.darkstar@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Dmitriy Matrosov <sgf.dma@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
To fix a nasty bug in ldisc hup vs. reinit we need to wait infinitely
long for ldisc to be gone. So here we add a parameter to
tty_ldisc_wait_idle to allow that.
This is only a preparation for the real fix which is done in the
following patches.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Dave Young <hidave.darkstar@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Dmitriy Matrosov <sgf.dma@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This reverts commit 9636b755da.
It wasn't supposed to be applied, thanks to Doug for letting me know.
Cc: Doug Anderson <dianders@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Extract ASYNC_INITIALIZED/TTY_IO_ERROR handling from uart_startup.
This will be useful for tty port helpers. These flags are handled
by the helpers instead.
So we create a new function uart_port_startup without touching these
flags there. And we keep uart_startup with the exact behavior as
before. We need that one because we start/stop the device from other
paths than open/close/hangup.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Let's fill the port_ops->shutdown. We will need this for hangup and
close port helpers.
We don't need to touch DTR/RTS registers in uart_port_shutdown. They
are set to off from port_close_start properly already.
Also we don't need to pin the TTY_IO_ERROR bit. This will be done in
close/hangup paths.
We leave uart_shutdown as is, because it is used (and will be) from
several paths now. Like from suspend.
The point is to not touch ASYNC_INITIALIZED bit. It will be set (and
checked) properly by the tty port helpers.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is a preparation for the next patches which will move the stuff
from uart_open and uart_close/hangup here. Then we will use
tty_port_* helpers.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
