The property in device tree will be reading each time when tty is opened,
so the ops of serial port should be set after that instead of setting once
in probe. Otherwise, the ops of serial port is inconsistent with the state
of serial work manner. For example, the atmel serial driver can't work when
switching to PIO mode due to DMA channel is not available.
Signed-off-by: Leilei Zhao <leilei.zhao@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function of atmel_init_property is to set the work manner of
atmel serial ports according to the property in device trees.
If DMA or PDC is not set or something goes wrong in getting property,
the work manner will switch to general PIO mode, thus there will
not be any failure case in this function. It's actually a procedure.
So changing the return type from int to void.
Signed-off-by: Leilei Zhao <leilei.zhao@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The buffer size set in DMA is inconsistent with its allocation.
So keep them consistent here. The structure atmel_uart_char is
used in PIO mode with its meaning. But here in DMA, all of the
buffer is treated as general char.
Signed-off-by: Leilei Zhao <leilei.zhao@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We only use buf of ring In DMA rx function while using buf of xmit
in DMA tx function. So in DMA rx we need definitively to check the
buf of ring which is corresponding to DMA rx function. And use macro
PAGE_ALIGNED to simplify the expression.
Signed-off-by: Leilei Zhao <leilei.zhao@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix a race condition that happens when device_initcall(pl011_dma_initicall)
is executed before all the devices have been probed - this issue was observed on
a hisi_6220 SoC (HiKey board from Linaro).
The deferred driver probing framework relies on late_initcall to trigger
deferred probes so it is just possible that, even with a valid DMA driver ready
to be loaded, we fail to synchronize with it.
The proposed implementation delays probing the DMA until dma_startup.
As this is invoked on port startup and port resume - but DMA probing is only
required once - we avoid calling multiple times using a new field in
uart_amba_port to track this scenario.
This commit allows for subsequent attempts to associate an external DMA if the
DMA driver itself is not available (but present in the deferred probe pending
list).
Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Getting the TX IRQ re-asserted from scratch can be inefficient in
some setups.
This patch avoids clearing the TX IRQ across pl011_shutdown()...
pl011_startup(), so that if the port is closed and reopened, the
IRQ will still work afterwards without having to bootstrap it again.
The TX IRQ continues to be masked in IMSC when the UART is not in
use.
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current PL011 driver transmits a dummy character when the UART
is opened, to assert the TX IRQ for the first time
(see pl011_startup()). The UART is put in loopback mode temporarily,
so the receiver presumably shouldn't see anything.
However...
At least some platforms containing a PL011 send characters down the
wire even when loopback mode is enabled. This means that a
spurious NUL character may be seen at the receiver when the PL011 is
opened through the TTY layer.
The current code also temporarily sets the baud rate to maximum and
the character width to the minimum, to that the dummy TX completes
as quickly as possible. If this is seen by the receiver it will
result in a framing error and can knock the receiver out of sync --
turning subsequent output into garbage until synchronisation
is reestablished. (Particularly problematic during boot with systemd.)
To avoid spurious transmissions, this patch removes assumptions about
whether the TX IRQ will fire until at least one TX IRQ has been seen.
Instead, the UART will unmask the TX IRQ and then slow-start via
polling and timer-based soft IRQs initially. If the TTY layer writes
enough data to fill the FIFO to the interrupt threshold in one go,
the TX IRQ should assert, at which point the driver changes to
fully interrupt-driven TX.
In this way, the TX IRQ is activated as a side-effect instead of
being done deliberately.
This should also mean that the driver works on the SBSA Generic
UART[1] (a cut-down PL011) without invasive changes. The Generic
UART lacks some features needed for the dummy TX approach to work
(FIFO disabling and loopback).
[1] Server Base System Architecture (ARM-DEN-0029-v2.3)
http://infocenter.arm.com/
(click-thru required :/)
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently tty_wait_until_sent may take up to twice as long as the
requested timeout while waiting for driver and hardware buffers to
drain.
Fix this by taking the remaining number of jiffies after waiting for
driver buffers to drain into account so that the timeout actually
becomes a maximum timeout as it is documented to be.
Note that this specifically implies tighter timings when closing a port
as a consequence of actually honouring the port closing-wait setting
for drivers relying on tty_wait_until_sent_from_close (e.g. via
tty_port_close_start).
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix overflow bug in tty_wait_until_sent on 64-bit machines, where an
infinite timeout (0) would be passed to the underlying tty-driver's
wait_until_sent-operation as a negative timeout (-1), causing it to
return immediately.
This manifests itself for example as tcdrain() returning immediately,
drivers not honouring the drain flags when setting terminal attributes,
or even dropped data on close as a requested infinite closing-wait
timeout would be ignored.
The first symptom was reported by Asier LLANO who noted that tcdrain()
returned prematurely when using the ftdi_sio usb-serial driver.
Fix this by passing 0 rather than MAX_SCHEDULE_TIMEOUT (LONG_MAX) to the
underlying tty driver.
Note that the serial-core wait_until_sent-implementation is not affected
by this bug due to a lucky chance (comparison to an unsigned maximum
timeout), and neither is the cyclades one that had an explicit check for
negative timeouts, but all other tty drivers appear to be affected.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org> # v2.6.12
Reported-by: ZIV-Asier Llano Palacios <asier.llano@cgglobal.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove incorrect and redundant wait_until_sent operation, which waits
for the driver buffer rather than any hardware buffers to drain,
something which is already taken care of by the tty layer (and
chars_in_buffer).
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix return from sprd_handle_irq() with spin_lock held.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All instances of "ttyPS" use this macro except for this one. Convert
it.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Spreadtrum UART is accessed with mmio; declare the proper iotype.
Also prevent userspace from assigning any other iotype via
ioctl(TIOCSSERIAL).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The transmitter is expected to be controlled by the UART's RTS pin.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Support for IRDA was added in 2009 in commit v2.6.31-rc1~399^2~2. There
are no in-tree users.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no benefit in keeping this information in RAM when it's not
used any more, so better use function local variables instead.
These members are unused since c0d1c6b0f0dc ("serial: imx: Fix the
reporting of interrupts")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This if (0) exists since the driver was introduced in commit
c49bde83eb6a ([ARM PATCH] 1956/2: Re: Motorola i.MX serial driver)
back in 2004.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The writeable bits in the USR2 register are all "write 1 to
clear" so only write the bits that actually should be cleared.
Fixes: f1f836e4209e ("serial: imx: Add Rx Fifo overrun error message")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since we have a native 8250 driver carrying the Intel MID serial devices the
specific support is not needed anymore. This patch removes it for Intel MID.
Note that the console device name is changed from ttyMFDx to ttySx.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Intel Penwell supports 3 HSUART ports which are 8250 compatible. The patch adds
necessary bits to the driver.
The functions have intel_mid_* prefix due to more than one platform will use
this code.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Current code uses the alias id as array subscript of ar933x_console_ports.
So the valid id is 0 ... CONFIG_SERIAL_AR933X_NR_UARTS - 1.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Instead of ignoring errors returned by devm_gpiod_get_index use
devm_gpiod_get_index_optional which results in slightly more strict
error handling which is good.
Also use the fourth parameter to devm_gpiod_get_index_optional to be
able to drop the explicit direction setting.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers using mctrl-gpio must not pass invalid values for struct
mctrl_gpios *. All drivers were fixed in this regard and so some checks
can go away or be simplified.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If mctrl_gpio_init returns an error code this value should be forwarded and
the driver must not simply ignore this failure.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mctrl_gpio_init is fully aware of being optional. If it returns an error
code this indicates a real error that must not be ignored.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mctrl_gpio_init at present doesn't return NULL. (It might be used in the
future when no gpios are to be used indicating success.) Properly pass
error returned and also make driver probing fail on error.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is only an API consolidation and should make things more readable
it replaces var * HZ / 1000 by msecs_to_jiffies(var).
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
UBRC is a read-only register, so we should not store and restore it inside
imx_flush_buffer().
Reported-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
this patch fixes following sparse warnings:
bcm63xx_uart.c:857:43: warning: Using plain integer as NULL pointer
bcm63xx_uart.c:871:35: warning: Using plain integer as NULL pointer
Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Without this the module does not load automatically whenever suitable
platform device appears.
Reported-by: Jerome Blin <jerome.blin@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Building sprd_serial.o when CONFIG_PM_SLEEP is not defined triggers
these warnings:
drivers/tty/serial/sprd_serial.c:755:12: warning: ‘sprd_suspend’ defined but not used [-Wunused-function]
static int sprd_suspend(struct device *dev)
^
drivers/tty/serial/sprd_serial.c:764:12: warning: ‘sprd_resume’ defined but not used [-Wunused-function]
static int sprd_resume(struct device *dev)
^
Let's compile these functions only when CONFIG_PM_SLEEP is defined.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert the legacy system PM callbacks to new ones. Meanwhile, remove the
redudant calls to the PCI for changing a power state since it's done by bus
code.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the current kernel, the CONFIG_PPC_OF is always 'y' for the ppc
arch. So we don't need to check it with other ppc specific options.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use helper functions to access current->state.
Direct assignments are prone to races and therefore buggy.
Thanks to Peter Zijlstra for the exact definition of the problem.
Suggested-By: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As more ARM platforms are moving into ARCH_MULTIPLATFORM, we can now
have integrator and versatile in the same kernel, and first one selects
this driver, causing a Kconfig warning:
warning: (ARCH_INTEGRATOR_AP) selects SERIAL_AMBA_PL010 which has unmet direct dependencies (TTY && HAS_IOMEM && ARM_AMBA && (BROKEN || !ARCH_VERSATILE))
It turns out that it has not been broken on versatile for a long time,
so we can remove the statement here.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This problem was taken care of three times already in
* b0de59b5733d18b0d1974a060860a8b5c1b36a2e (TTY: do not update
atime/mtime on read/write),
* 37b7f3c76595e23257f61bd80b223de8658617ee (TTY: fix atime/mtime
regression), and
* b0b885657b6c8ef63a46bc9299b2a7715d19acde (tty: fix up atime/mtime
mess, take three)
But it still misses one point. As John Paul correctly points out, we
do not care about setting date. If somebody ever changes wall
time backwards (by mistake for example), tty timestamps are never
updated until the original wall time passes.
So check the absolute difference of times and if it large than "8
seconds or so", always update the time. That means we will update
immediatelly when changing time. Ergo, CAP_SYS_TIME can foul the
check, but it was always that way.
Thanks John for serving me this so nicely debugged.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: John Paul Perry <john_paul.perry@alcatel-lucent.com>
Cc: <stable@vger.kernel.org> # all, as b0b885657 was backported
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixed behaviour of get_mctrl() serial driver function as documented in:
https://www.kernel.org/doc/Documentation/serial/driver
Added device-tree properties 'dcd-override', 'dsr-override',
'cts-override', and 'ri-override' specific to the Synopsis 8250
DesignWare UART driver. Allows one to force Data Carrier Detect,
Clear To Send, and Data Set Ready signals to permanently be reported as
active. The Ring indicator can be forced to be reported as inactive.
It is possible that if modem control signalling is enabled on a port
that doesn't have these pins (e.g. - a simple two wire Tx/Rx port), the
driver can hang indefinitely waiting for the state to change. The new
DT properties allow the driver to ignore the state of these pins on
serial ports that don't support them, as recommended in the kernel
documentation.
Reviewed-by: JD (Jiandong) Zheng <jdzheng@broadcom.com>
Signed-off-by: Jonathan Richardson <jonathar@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These quirk entries have the same effect as default
quirk entry, so we can just delete them.
Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 8b5c913f7ee6464849570bacb6bcd9ef0eaf7dce
("serial: 8250_pci: Add WCH CH352 quirk to avoid Xscale detection")
trigger one redundant entry report message.
This patch fix it.
Reported-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I'm still receiving reports to my email address, so let's point this
at the linux-serial mailing list instead.
Cc: <stable@vger.kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 0aa525d11859c1a4d5b78fdc704148e2ae03ae13.
The conditional RX-FIFO read seems to cause spurious interrupts and we
see just:
|serial8250: too much work for irq29
The previous behaviour was "default" for decades and Marvell's 88f6282 SoC
might not be the only that relies on it. Therefore the Omap fix is
reverted for now.
Fixes: 0aa525d11859 ("tty: serial: 8250_core: read only RX if there is
something in the FIFO")
Reported-By: Nicolas Schichan <nschichan@freebox.fr>
Debuged-By: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 6d01bb9dc82a60580f749062a48cb47cd5caca07.
The exact same code was added in commit 3239fd31d4 (serial: of-serial: fetch
line number from DT) a few lined above. Doing this once should be enough.
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We never report the error because we don't assign it to ret.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The IRQ line connected to the DBGU UART is often shared with a timer device
which request the IRQ with IRQF_NO_SUSPEND.
Since the UART driver is correctly disabling IRQs when entering suspend
we can safely request the IRQ with IRQF_COND_SUSPEND so that irq core
will not complain about mixing IRQF_NO_SUSPEND and !IRQF_NO_SUSPEND.
Rework the interrupt handler to wake the system up when an interrupt
happens on the DEBUG_UART while the system is suspended.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
