The work-around for the Qualcomm Datacenter Technologies QDF2400
erratum 44 sets the "qdf2400_e44_present" global variable if the
work-around is needed. However, this check does not happen until after
earlycon is initialized, which means the work-around is not
used, and the console hangs as soon as it displays one character.
Fixes: d8a4995bce ("tty: pl011: Work around QDF2400 E44 stuck BUSY bit")
Signed-off-by: Timur Tabi <timur@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit d0aeaa83f0 ("serial: exar:
split out the exar code from 8250_pci") the exar driver got its own
Kconfig. However the text for the new option was never changed from
the original 8250_PCI text, and hence it appears confusing when you
get asked the same question twice:
8250/16550 PCI device support (SERIAL_8250_PCI) [Y/n/m/?] (NEW)
8250/16550 PCI device support (SERIAL_8250_EXAR) [Y/n/m] (NEW)
Adding to the confusion, is that there is no help text for this new
option to indicate it is specific to a certain family of cards.
Fix both issues at the same time, as well as the space vs. tab issues
introduced in the same commit.
Fixes: d0aeaa83f0 ("serial: exar: split out the exar code from 8250_pci")
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A side effect of 89d8232411 ("tty/serial: atmel_serial: BUG: stop DMA
from transmitting in stop_tx") is that the console can be called with
TX path disabled. Then the system would hang trying to push charecters
out in atmel_console_putchar().
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Fixes: 89d8232411 ("tty/serial: atmel_serial: BUG: stop DMA from transmitting
in stop_tx")
Cc: stable <stable@vger.kernel.org> #4.4+
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If uart_flush_buffer() is called between atmel_tx_dma() and
atmel_complete_tx_dma(), the circular buffer has been cleared, but not
atmel_port->tx_len.
That leads to a circular buffer overflow (dumping (UART_XMIT_SIZE -
atmel_port->tx_len) bytes).
Tested-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Cc: stable <stable@vger.kernel.org> # 3.12+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The reference manual for the i.MX28 recommends to calculate the divisor
as
divisor = (UARTCLK * 32) / baud rate, rounded to the nearest integer
, so let's do this. For a typical setup of UARTCLK = 24 MHz and baud
rate = 115200 this changes the divisor from 6666 to 6667 and so the
actual baud rate improves from 115211.521 Bd (error ≅ 0.01 %) to
115194.240 Bd (error ≅ 0.005 %).
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are some tty and serial driver fixes for 4.11-rc4. One of these
fix a long-standing issue in the ldisc code that was found by Dmitry
Vyukov with his great fuzzing work. The other fixes resolve other
reported issues, and there is one revert of a patch in 4.11-rc1 that
wasn't correct.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver fixes from Greg KH:
"Here are some tty and serial driver fixes for 4.11-rc4.
One of these fix a long-standing issue in the ldisc code that was
found by Dmitry Vyukov with his great fuzzing work. The other fixes
resolve other reported issues, and there is one revert of a patch in
4.11-rc1 that wasn't correct.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-4.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: fix data race in tty_ldisc_ref_wait()
tty: don't panic on OOM in tty_set_ldisc()
Revert "tty: serial: pl011: add ttyAMA for matching pl011 console"
tty: acpi/spcr: QDF2400 E44 checks for wrong OEM revision
serial: 8250_dw: Fix breakage when HAVE_CLK=n
serial: 8250_dw: Honor clk_round_rate errors in dw8250_set_termios
- Set the parent on the Altera A10SR driver, also fix
high level IRQs.
- Fix error path on the mockup driver.
- Compilation noise about unused functions fixed.
- Fix missed interrupts on the MCP23S08 expander, this is also
tagged for stable.
- Retire the interrim helpers devm_get_gpiod_from_child() used
to smoothen merging in the merge window.
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Merge tag 'gpio-v4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO fixes from Linus Walleij:
"Here is the first set of GPIO fixes for 4.11. It was delayed a bit
beacuse I was chicken when linux-next was not rotating last week.
This hits the ST serial driver in drivers/tty/serial and that has an
ACK from Greg, he suggested to keep the old GPIO fwnode API around to
smoothen things in the merge Windod and those have now served their
purpose so we take them out and convert the last driver to the new
API.
Apart from that it's fixes as usual.
Summary:
- set the parent on the Altera A10SR driver, also fix high level
IRQs.
- fix error path on the mockup driver.
- compilation noise about unused functions fixed.
- fix missed interrupts on the MCP23S08 expander, this is also tagged
for stable.
- retire the interrim helpers devm_get_gpiod_from_child() used to
smoothen merging in the merge window"
* tag 'gpio-v4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
gpio:mcp23s08 Fixed missing interrupts
serial: st-asc: Use new GPIOD API to obtain RTS pin
gpio: altera: Use handle_level_irq when configured as a level_high
gpio: xgene: mark PM functions as __maybe_unused
gpio: mockup: return -EFAULT if copy_from_user() fails
gpio: altera-a10sr: Set gpio_chip parent property
The original patch makes the condition always true, so it is wrong.
It masks (but not fixes) the bug described in the commit message
but introduces a regression (no console is selected by SPCR)
in regular (no 'console=ttyAMA') case.
s/||/&&/ would not fix the problem as the root cause was identified
incorrectly.
This reverts commit aea9a80ba9.
Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Jayachandran C <jnair@caviumnetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commits mentioned below adapt the GPIO API to allow more information
to be passed directly through devm_get_gpiod_from_child() in the first
instance. This facilitates the removal of subsequent calls, such as
gpiod_direction_output(). This patch firstly moves to utilise the new
API and secondly removes the now superfluous call do set the direction.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Suggested-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[Also drop the header file dummies that only this driver was using]
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Commit 6a171b2993 ("serial: 8250_dw: Allow hardware flow control to be
used") recently broke the 8250_dw driver on platforms which don't select
HAVE_CLK, as dw8250_set_termios() gets confused by the behaviour of the
fallback HAVE_CLK=n clock API in linux/clk.h which pretends everything
is fine but returns (valid) NULL clocks and 0 HZ clock rates.
That 0 rate is written into the uartclk resulting in a crash at boot,
e.g. on Cavium Octeon III based UTM-8 we get something like this:
1180000000800.serial: ttyS0 at MMIO 0x1180000000800 (irq = 41, base_baud = 25000000) is a OCTEON
------------[ cut here ]------------
WARNING: CPU: 2 PID: 1 at drivers/tty/serial/serial_core.c:441 uart_get_baud_rate+0xfc/0x1f0
...
Call Trace:
...
[<ffffffff8149c2e4>] uart_get_baud_rate+0xfc/0x1f0
[<ffffffff814a5098>] serial8250_do_set_termios+0xb0/0x440
[<ffffffff8149c710>] uart_set_options+0xe8/0x190
[<ffffffff814a6cdc>] serial8250_console_setup+0x84/0x158
[<ffffffff814a11ec>] univ8250_console_setup+0x54/0x70
[<ffffffff811901a0>] register_console+0x1c8/0x418
[<ffffffff8149f004>] uart_add_one_port+0x434/0x4b0
[<ffffffff814a1af8>] serial8250_register_8250_port+0x2d8/0x440
[<ffffffff814aa620>] dw8250_probe+0x388/0x5e8
...
The clock API is defined such that NULL is a valid clock handle so it
wouldn't be right to check explicitly for NULL. Instead treat a
clk_round_rate() return value of 0 as an error which prevents uartclk
being overwritten.
Fixes: 6a171b2993 ("serial: 8250_dw: Allow hardware flow control to be used")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: linux-serial@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: bcm-kernel-feedback-list@broadcom.com
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Jason Uy <jason.uy@broadcom.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
clk_round_rate returns a signed long and may possibly return errors
in it, for example if there is no possible rate.
Till now dw8250_set_termios ignored any error, the signednes and would
just use the value as input to clk_set_rate. This of course falls apart
if there is an actual error, so check for errors and only try to set
a rate if the value is actually valid.
This turned up on some Rockchip platforms after commit
6a171b2993 ("serial: 8250_dw: Allow hardware flow control to be used")
enabled set_termios callback in all cases, not only ACPI.
Fixes: 6a171b2993 ("serial: 8250_dw: Allow hardware flow control to be used")
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If DMA is not available (even when configured in DeviceTree), the driver
will fail the startup procedure thus making serial console not
available.
For example this causes boot failure on QEMU ARMv7 (Exynos4210, SMDKC210):
[ 1.302575] OF: amba_device_add() failed (-19) for /amba/pdma@12680000
...
[ 11.435732] samsung-uart 13800000.serial: DMA request failed
[ 72.963893] samsung-uart 13800000.serial: DMA request failed
[ 73.143361] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000000
DMA is not necessary for serial to work, so continue with UART startup
after emitting a warning.
Fixes: 62c37eedb7 ("serial: samsung: add dma reqest/release functions")
Cc: <stable@vger.kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix up affected files that include this signal functionality via sched.h.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to move scheduler ABI details to <uapi/linux/sched/types.h>,
which will be used from a number of .c files.
Create empty placeholder header that maps to <linux/types.h>.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix typos and add the following to the scripts/spelling.txt:
comsume||consume
comsumer||consumer
comsuming||consuming
I see some variable names with this pattern, but this commit is only
touching comment blocks to avoid unexpected impact.
Link: http://lkml.kernel.org/r/1481573103-11329-19-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now we can also jump to boot prom from sunhv console by sending
break twice on console for both running and panicked kernel
cases.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On panic, all other CPUs are stopped except the one which had
hit panic. To keep console alive, we need to migrate hvcons irq
to panicked CPU.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Qualcomm Datacenter Technologies QDF2400 family of SoCs contains a
custom (non-PrimeCell) implementation of the SBSA UART. Occasionally the
BUSY bit in the Flag Register gets stuck as 1, erratum 44 for both 2432v1
and 2400v1 SoCs.Checking that the Transmit FIFO Empty (TXFE) bit is 0,
instead of checking that the BUSY bit is 1, works around the issue.
To facilitate this substitution of flags and values, introduce
vendor-specific inversion of Feature Register bits when UART AMBA Port
(UAP) data is available. For the earlycon case, prior to UAP availability,
implement alternative putc and early_write functions.
Similar to what how ARMv8 ACPI PCI quirks are detected during MCFG parsing,
check the OEM fields of the Serial Port Console Redirection (SPCR) ACPI
table to determine if the current platform is known to be affected by the
erratum.
Signed-off-by: Christopher Covington <cov@codeaurora.org>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Timur Tabi <timur@codeaurora.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The fractional baud rate generator is available when using the
asynchronous mode of Atmel USART controllers. It makes it possible to
use higher baudrates, in exchange for a less precise clock with a
variable duty cycle.
The existing code restricts its use to the normal mode of the USART
controller, following the recommendation from the datasheet for the
first chip embedding this type of controller. This recommendation has
been removed from the documentation for the newer chips. After
verification, all revisions of this controller should be able to use the
fractional baud rate generator with the different asynchronous modes.
Removing the condition on ATMEL_US_USMODE makes it possible to get
correct baudrates at high speed in more cases.
This was tested with a board using an Atmel SAMA5D2 chip and a TI
WL1831 WiFi/Bluetooth combo chip at 3 Mbauds, with hardware flow control
enabled.
Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use pci_alloc_irq_vectors to enable MSI when available. At least the
XR17V352 supports this.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
None of these registers is relevant for the userspace API.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Became obsolete with the split-out of 8250_exar.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Those are Exar-based, too.
With the required refactoring of the code to fit into 8250_exar, we
automatically fix the same issue pci_xr17v35x_setup had before: 8XMODE,
FCTL, TXTRG and RXTRG were always only set for port 0. Now they are
initialized for the correct target port by using port.membase.
Now we can also cleanly fix the blacklist of 8250_pci so that all
Commtech devices are rejected and 8250_exar can handle them.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
So far, pci_xr17v35x_setup always initialized 8XMODE, FCTR & Co. for
port 0 because it used the address of that port instead of moving the
pointer according to the port number. Fix this and remove the unneeded
temporary ioremap by moving default_setup up and reusing the membase it
fills into the port structure.
Fixes: 14faa8cce8 ("tty/8250 Add support for Commtech's Fastcom Async-335 and Fastcom Async-PCIe cards")
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pcim_iomap_table only returns the table of mapping, it does not perform
them. For that, we need to call pcim_iomap, but only if that mapping was
not done before.
Fixes: d0aeaa83f0 ("serial: exar: split out the exar code from 8250_pci")
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1. Do not set the RX trigger level for software timeout devices on reset;
there is no timeout by default, and data will rot.
2. Do set the RX trigger level for hardware timeout devices when set
via sysfs attribute.
Fixes SCIFA-type serial consoles.
Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When going to suspend, the UART registers may be lost because the power to
VDDcore is cut. This is not an issue in the normal case but when
no_console_suspend is used, we need to restore the registers in order to
get a functional console.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On a Rockchip rk3399-based board during suspend/resume testing, we
found that we could get the console UART into a state where it would
print this to the console a lot:
serial8250: too much work for irq42
Followed eventually by:
NMI watchdog: BUG: soft lockup - CPU#0 stuck for 11s!
Upon debugging I found that we're in this state:
iir = 0x000000cc
lsr = 0x00000060
It appears that somehow we have a RX Timeout interrupt but there is no
actual data present to receive. When we're in this state the UART
driver claims that it handled the interrupt but it actually doesn't
really do anything. This means that we keep getting the interrupt
over and over again.
Normally we don't actually need to do anything special to handle a RX
Timeout interrupt. We'll notice that there is some data ready and
we'll read it, which will end up clearing the RX Timeout. In this
case we have a problem specifically because we got the RX TImeout
without any data. Reading a bogus byte is confirmed to get us out of
this state.
It's unclear how exactly the UART got into this state, but it is known
that the UART lines are essentially undriven and unpowered during
suspend, so possibly during resume some garbage / half transmitted
bits are seen on the line and put the UART into this state.
The UART on the rk3399 is a DesignWare based 8250 UART. From mailing
list posts, it appears that other people have run into similar
problems with DesignWare based IP. Presumably this problem is unique
to that IP, so I have placed the workaround there to avoid possibly of
accidentally triggering bad behavior on other IP. Also note the RX
Timeout behaves very differently in the DMA case, for for now the
workaround is only applied to the non-DMA case.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes the following sparse warning:
drivers/tty/serial/8250/8250_pci.c:3916:6: warning:
symbol 'pciserial_detach_ports' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The initial binding 'st,hw-flow-control' isn't used anywhere, in neither
in upstream nor downstream kernels. It isn't even documented in
dt-bindings, so we can safely assume it's safe to swap to the generic
one.
Acked-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When hardware flow-control is disabled, manual toggling of the UART's
reset line (RTS) using userland applications (e.g. stty) is not
possible, since the ASC IP does not provide this functionality in the
same was as some other IPs do. Thus, we have to do this manually.
This patch ensures that when HW flow-control is disabled the RTS/CTS
lines are free to be registered via the GPIO API. It also ensures
any registered GPIO lines are unregistered when HW flow-control is
requested, allowing the IP to control them automatically.
Acked-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are now 2 possible separate/different Pinctrl states which can
be provided from platform data. One which encompasses the lines
required for HW flow-control (CTS/RTS) and another which does not
specify these lines, such that they can be used via GPIO mechanisms
for manually toggling (i.e. from a request by `stty`).
Acked-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Until this point, it has not been possible for userland serial
applications (e.g. stty) to toggle the UART RTS line. This can
be useful with certain configurations. For example, when using
a Mezzanine on a Linaro 96board, RTS line is used to take the
on-board microcontroller in and out of reset.
Acked-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The datasheet states:
"If the MODE field selects an 8-bit frame then this [parity error] bit
is undefined. Software should ignore this bit when reading 8-bit frames."
Acked-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The MKS Instruments SCOM-0800 and SCOM-0801 cards (originally by Tenta
Technologies) are 3U CompactPCI serial cards with 4 and 8 serial ports,
respectively. The first 4 ports are implemented by an OX16PCI954 chip,
and the second 4 ports are implemented by an OX16C954 chip on a local
bus, bridged by the second PCI function of the OX16PCI954. The ports
are jumper-selectable as RS-232 and RS-422/485, and the UARTs use a
non-standard oscillator frequency of 20 MHz (base_baud = 1250000).
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Allows tuning of the RX FIFO fill threshold and timeout. (The latter is
only applicable to SCIFA and SCIFB).
Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implements support for FIFO fill thresholds greater than one with software
timeout.
This mechanism is not possible (or at least not useful) on SCIF family
hardware other than SCIFA and SCIFB because they do not support turning off
the DR hardware timeout interrupt separately from the RI interrupt.
Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sets reasonable trigger defaults for the various SCIF variants.
Also corrects the FIFO size for SH7705-style ports.
Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To allow operation with a higher RX FIFO interrupt threshold in PIO
mode, it is necessary to consider the DR bit ("FIFO not full, but no
data received for 1.5 frames") as an indicator that data can be read.
Otherwise the driver will let data rot in the FIFO until the threshold
is reached.
Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit c7cef0a849 ("console: Add extensible console matching") added
match() method to struct console which allows the console to perform
console command line matching instead of (or in addition to) default
console matching (ie., by fixed name and index).
Commit ad1696f6f0 ("ACPI: parse SPCR and enable matching console")
introduced support for SPCR as matching console.
Commit 10879ae5f1 ("serial: pl011: add console matching function")
added the match method for pl011 console which checks for the console
string to be "pl011"
Now on a platform which has both SPCR in the ACPI tables and ttyAMA in
the command line, the ttyAMA is chosen as "selected console" but it
doesn't pass the matching console method which results in CON_CONSDEV
not being set on the "selected console".
As a result of that, the bootconsole(SPCR in the above case) is not
unregistered and all the beginning boot messages are seen twice.
This patch adds "ttyAMA" so that it's considered to match pl011 console.
Fixes: 10879ae5f1 ("serial: pl011: add console matching function")
Cc: Russell King <linux@armlinux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Aleksey Makarov <aleksey.makarov@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ensure that the uart clock is enabled prior to writing to the
interrupt mask register in s3c24xx_serial_resume_noirq function.
Without enabing the uart clock, the uart register cannot be accessed.
Signed-off-by: Youngmin Nam <youngmin.nam@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove the Exar specific codes from 8250_pci and blacklist those chips
so that the new Exar serial driver binds to the devices.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add the serial driver for the Exar chips. And also register the
platform device for the GPIO provided by the Exar chips.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When userspace passes the SER_RS485_RTS_ON_SEND flag it means that the
CTS_B pin should go to logic level high before the transmission begins.
CTS_B goes to logic level high when both CTSC and CTS bits are cleared.
When userspace passes the SER_RS485_RTS_AFTER_SEND flag it means that the
CTS_B pin should go to logic level low after the transmission finishes.
CTS_B goes to logic level low when CTSC bit is cleared and CTS bit is set.
So fix the CTS_B polarity logic.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On a board that needs to drive RTS GPIO high in order to enable the
transmission of a RS485 transceiver the following description is
passed in the devide tree:
&uart4 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart4>;
rts-gpios = <&gpio6 2 GPIO_ACTIVE_HIGH>;
status = "okay";
};
and userspace configures the uart port as follows:
/* enable RS485 mode: */
rs485conf.flags |= SER_RS485_ENABLED;
/* set logical level for RTS pin equal to 1 when sending: */
rs485conf.flags |= SER_RS485_RTS_ON_SEND;
/* set logical level for RTS pin equal to 0 after sending: */
rs485conf.flags &= ~(SER_RS485_RTS_AFTER_SEND);
However the RTS GPIO polarity observed in the oscilloscope is inverted.
When the SER_RS485_RTS_ON_SEND flag is set the imx_port_rts_active()
function should be called and following the same logic when
SER_RS485_RTS_AFTER_SEND flag is cleared the imx_port_rts_inactive()
should be called.
Do such logic change so that RS485 communication in half duplex can
work successfully when the RTS GPIO pin is passed via device tree.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
During build testing, I ran into a warning in a driver that I
had written myself at some point:
drivers/tty/serial/8250/8250_of.c: In function 'of_platform_serial_probe':
drivers/tty/serial/8250/8250_of.c:233:1: error: the frame size of 1200 bytes is larger than 1152 bytes [-Werror=frame-larger-than=]
This is harmless by itself, but it shows two other problems in
the driver:
- It still tries to be generic enough to handle all kinds of serial
ports, where in reality the driver has been 8250-only for a while,
and every other uart has its own DT support
- As a result of that generalization, we keep two copies of
'struct uart_port' on the stack during probe(). This is completely
unnessary.
Removing the last code dealing with unsupported port_type values
solves both problems nicely, and reduces the stack size.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As the function header of sci_parse_dt() is split in an unusual way,
"git diff" gets confused when changes to the body of the function are
made, and attributes them to the wrong function.
Reformat the function header to fix this.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Timur Tabi