Describes the calculation of the UART baud rate clock using a clock
frame. Forgot to add in Kconfig kernel test Robot compilation error
due to COMMON_CLK dependency.
Fixes: 44023b8e1f ("tty: serial: meson: Describes the calculation of the UART baud rate clock using a clock frame")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220228064910.11636-1-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Having a generic UART_LCR_WLEN() macro and the tty_get_char_size()
helper, we can remove all those repeated switch-cases in drivers.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220224095558.30929-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Having a generic UART_LCR_WLEN() macro and the tty_get_char_size()
helper, we can remove all those repeated switch-cases in drivers.
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: linux-tegra@vger.kernel.org
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220224095558.30929-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add Sunplus SoC UART Driver.
SP7021 UART block contains 5 UARTs.
There are UART0~4 that supported in SP7021, the features list as below.
Support Full-duplex communication.
Support data packet length configurable.
Support stop bit number configurable.
Support force break condition.
Support baud rate configurable.
Support error detection and report.
Support RXD Noise Rejection Vote configurable.
UART0 pinout only support TX/RX two pins.
UART1 to UART4 pinout support TX/RX/CTS/RTS four pins.
Normally UART0 used for kernel console, also can be used for normal uart.
Command line set "console=ttySUP0,115200", SUP means Sunplus Uart Port.
UART driver probe will create path named "/dev/ttySUPx".
https://sunplus.atlassian.net/wiki/spaces/doc/pages/1873412290/13.+Universal+Asynchronous+Receiver+Transmitter+UART
Signed-off-by: Hammer Hsieh <hammerh0314@gmail.com>
Link: https://lore.kernel.org/r/1645522563-17183-3-git-send-email-hammerh0314@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Set em485->active_timer = NULL isn't always enough to take out the stop
timer. While there is a check that it acts in the right state (i.e.
waiting for RTS-after-send to pass after sending some chars) but the
following might happen:
- CPU1: some chars send, shifter becomes empty, stop tx timer armed
- CPU0: more chars send before RTS-after-send expired
- CPU0: shifter empty irq, port lock taken
- CPU1: tx timer triggers, waits for port lock
- CPU0: em485->active_timer = &em485->stop_tx_timer, hrtimer_start(),
releases lock()
- CPU1: get lock, see em485->active_timer == &em485->stop_tx_timer,
tear down RTS too early
This fix bases on research done by Steffen Trumtrar.
Fixes: b86f86e8e7 ("serial: 8250: fix potential deadlock in rs485-mode")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220215160236.344236-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Start the console and run the following commands in turn:
stty -F /dev/ttyAML0 115200 and stty -F /dev/ttyAML0 921600. The
system will stuck.
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-6-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make the internal clock source mux and divider writeable, allowing the
uart to deviate from the settings intially applied by the ROMCode and
using the most appropriate clocks.
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-5-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Using the common Clock code to describe the UART baud rate clock
makes it easier for the UART driver to be compatible with the
baud rate requirements of the UART IP on different meson chips.
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-4-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace devm_request_mem_region and devm_ioremap with
devm_ioremap_resource to make the code cleaner.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-3-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This simplifies resetting the UART controller during probe
and will make it easier to integrate the common clock code
which will require the registers at probe time as well.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-2-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are some small n_gsm and sc16is7xx serial driver fixes for
5.17-rc6.
The n_gsm fixes are from Siemens as it seems they are using the line
discipline and fixing up a number of issues they found in their testing.
The sc16is7xx serial driver fix is for a reported problem with that
chip.
All of these have been in linux-next with no reported problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver fixes from Greg KH:
"Here are some small n_gsm and sc16is7xx serial driver fixes for
5.17-rc6.
The n_gsm fixes are from Siemens as it seems they are using the line
discipline and fixing up a number of issues they found in their
testing. The sc16is7xx serial driver fix is for a reported problem
with that chip.
All of these have been in linux-next with no reported problems"
* tag 'tty-5.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
sc16is7xx: Fix for incorrect data being transmitted
tty: n_gsm: fix deadlock in gsmtty_open()
tty: n_gsm: fix wrong modem processing in convergence layer type 2
tty: n_gsm: fix wrong tty control line for flow control
tty: n_gsm: fix NULL pointer access due to DLCI release
tty: n_gsm: fix proper link termination after failed open
tty: n_gsm: fix encoding of command/response bit
tty: n_gsm: fix encoding of control signal octet bit DV
The code uses uart_amba_port::port on many places. Sometimes it even
needs not uart_amba_port itself. So simplify the code on many places
and remove the need of uart_amba_port on some places completely.
No functional changes intended. The objdump -d output shows only a code
move in pl010_rx_chars().
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Russell King <linux@armlinux.org.uk>
Link: https://lore.kernel.org/r/20220224111028.20917-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove the hello print among with version and name definitions. Drivers
should print nothing if they are successful.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220224111028.20917-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All these return bitmasks, so it makes more sense to return unsigned --
this is what a reader and also all the callers expect.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220224111028.20917-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The pci_get_slot() increases its reference count, the caller
must decrement the reference count by calling pci_dev_put().
Fixes: 9a1870ce81 ("serial: 8250: don't use slave_id of dma_slave_config")
Depends-on: a13e19cf3d ("serial: 8250_lpss: split LPSS driver to separate module")
Reported-by: Qing Wang <wangqing@vivo.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220223151240.70248-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The pci_get_slot() increases its reference count, the caller
must decrement the reference count by calling pci_dev_put().
Fixes: 90b9aacf91 ("serial: 8250_pci: add Intel Tangier support")
Fixes: f549e94eff ("serial: 8250_pci: add Intel Penwell ports")
Reported-by: Qing Wang <wangqing@vivo.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Depends-on: d9eda9bab2 ("serial: 8250_pci: Intel MID UART support to its own driver")
Link: https://lore.kernel.org/r/20220215100920.41984-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
coccinelle report:
./drivers/tty/serial/8250/8250_aspeed_vuart.c:85:8-16:
WARNING: use scnprintf or sprintf
./drivers/tty/serial/8250/8250_aspeed_vuart.c:174:8-16:
WARNING: use scnprintf or sprintf
./drivers/tty/serial/8250/8250_aspeed_vuart.c:127:8-16:
WARNING: use scnprintf or sprintf
Use sysfs_emit instead of scnprintf or sprintf makes more sense.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Yang Guang <yang.guang5@zte.com.cn>
Signed-off-by: David Yang <davidcomponentone@gmail.com>
Link: https://lore.kernel.org/r/fed40753603dac4d14b17970c88e6f5f936348c1.1644541843.git.yang.guang5@zte.com.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Correct the Kconfig help text for SERIAL_8250_LPSS, SERIAL_8250_MID and
SERIAL_8250_PERICOM configuration options for dedicated PCI UART drivers
that have been blacklisted in the generic PCI 8250 UART driver and as
from commit a13e19cf3d ("serial: 8250_lpss: split LPSS driver to
separate module"), commit d9eda9bab2 ("serial: 8250_pci: Intel MID
UART support to its own driver"), and commit fcfd3c09f4 ("serial:
8250_pci: Split out Pericom driver") respectively are not handled by
said driver anymore (rather than for extra features only, as the current
text indicates), and therefore require the respective dedicated drivers
to work at all.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2202121704560.34636@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement simple usage of fractional divisor. When main divisor D is too
large to represent requested baudrate then use divisor M from the
fractional divisor feature. All the M prescalers are set to the same and
maximal value 63, so the fractional part of the fractional divisor is not
used at all. We also determine upper limit for possible baudrates.
Experiments show that UART at baudrate 1500000 Bd with this configuration
is stable. So there is no need to implement complicated calculation of
fractional coefficients yet.
To use this feature with higher baudrates, it is required to use UART clock
provided by UART clock driver. Default boot xtal clock is not capable of
higher baudrates.
Reviewed-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Link: https://lore.kernel.org/r/20220219152818.4319-6-kabel@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement a new device driver for controlling UART clocks on Marvell
Armada 3700 SoC. This device driver is loaded for devices which match
the compatible string "marvell,armada-3700-uart-clock".
There are more pitfalls related to UART clocks:
- both UARTs use same parent clock source (which can be xtal or one of
the TBG clocks),
- if a TBG clock is used as the parent clock, there are two additional
divisors that can both be configured to divide the rate by 1, 2, ... 6,
but these divisors are again shared between the two UART controllers
on the SOC,
- the configuration of the parent clock source and divisors is done in
the address space of the first UART controller, UART1. Clocks can be
gated separately for UART1 and UART2, but this setting also lives in
the address space of UART1,
- Marvell's Functional Specification for Armada 3720 document has the
clock gating bits swapped, so the one described to gate UART1 clock
actually gates UART2 and vice versa,
- each UART has it's own "special divisor", and this uses the parent
clock described above. These divisors are configure in each UART's
address space separately.
Thus the driver for UART2 controller needs to have access to UART1
address space, since UART1 address space contains some bits exclusive
for UART2 and also some bits which are shared between UART1 and UART2.
Also, during boot, when early console is active on one of the UARTs,
and we want to switch parent clock from xtal (default) to TBG (to be
more flexible with baudrates), the driver changing UART clocks also
needs to be able to change the "special divisor", so that the baudrate
of earlycon is not changed when swtiching to normal console. Thus the
clock driver also needs to be able to access UART2 register space,
for UART2's "special divisor".
For these reasons, this new UART clock driver does not use
ioremap_resource(), but only ioremap() to prevent resource conflicts
between UART clock driver and UART driver.
We need to share only two 32-bit registers between the UART driver and
the UART clock driver:
- UART Clock Control
- UART 2 Baud Rate Divisor
Access to these two registers are protected by one spinlock to prevent
any conflicts. Access is required only during probing, when changing
baudrate or during suspend/resume.
Hardware can be configured to use one of following clocks as UART parent
clock: TBG-A-P, TBG-B-P, TBG-A-S, TBG-B-S, xtal. Not every clock is
usable for higher buadrates. Any subset can be specified in the
device-tree and the driver will choose the best one which also still
supports the mandatory baudrate of 9600 Bd. For smooth boot log output
it is needed to specify clock used by early console, otherwise garbage
would be printed on UART during probe of UART clock driver and
transitioning from early console to normal console.
We are implementing this to be able to configure TBG clock as UART
parent clock, which is required to be able to achieve higher baudrates
than 230400 Bd. We achieve this by referencing this new UART clock
device node in UART's device node. UART clock device driver
automatically chooses the best clock source for UART driver.
Until now, UART's device-tree node needed to reference one of the static
clocks (xtal or one of the TBGs) as parent clock in the `clocks`
phandle - the parent clock which was configured before booting the
kernel. If bootloader changed UART's parent clock, it needed to change
the `clocks` phandle in DTB correspondingly before booting.
From now on both the old mechanism (xtal or TBG referenced as parent
clock in `clocks` phandle) and the new one (UART clock referenced in the
`clocks` phandle) are supported, to provide full backward compatibility
with existing DTS files, full backward compatibility with existing boot
loaders, and to provide new features (runtime clock configuration to
allow higher baudrates than 230400 Bd). New features are available only
with new DTS files.
There was also a discussion about how the UART node and the
clock-controller node could be wrapped together in a new binding [1, 2].
As explained there, this is not possible if we want to keep backwards
compatibility with existing bootloaders, and thus we are doing this by
putting the UART clock-controller node inside the UART1 node.
[1] https://lore.kernel.org/linux-serial/20220120000651.in7s6nazif5qjkme@pali/
[2] https://lore.kernel.org/linux-serial/20220125204006.A6D09C340E0@smtp.kernel.org/
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Link: https://lore.kernel.org/r/20220219152818.4319-4-kabel@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Export only the GPIOs that are not shared with hardware modem control
lines. Introduce new device parameter indicating whether modem control
lines are available.
Signed-off-by: Lech Perczak <l.perczak@camlintechnologies.com>
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220221105618.3503470-4-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
RTS, DTR and LOOP bits can be updated in a single MCR register update.
This reduces the number of (slow) SPI/I2C bus transactions.
Signed-off-by: Lech Perczak <l.perczak@camlintechnologies.com>
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220221105618.3503470-3-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Preserve unaffected bits state when accessing EFR register. This
prevents hardware flow control bits from being cleared on enhanced
functions access.
Signed-off-by: Lech Perczak <l.perczak@camlintechnologies.com>
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220221105618.3503470-2-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Don't start the whole chain for TX if there is no data to send. This is
mostly relevant for rs485 mode as there might be rts-before-send and
rts-after-send delays involved.
Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220217211839.443039-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
UART drivers are meant to use the port spinlock within certain
methods, to protect against reentrancy. The sc16is7xx driver does
very little locking, presumably because when added it triggers
"scheduling while atomic" errors. This is due to the use of mutexes
within the regmap abstraction layer, and the mutex implementation's
habit of sleeping the current thread while waiting for access.
Unfortunately this lack of interlocking can lead to corruption of
outbound data, which occurs when the buffer used for I2C transmission
is used simultaneously by two threads - a work queue thread running
sc16is7xx_tx_proc, and an IRQ thread in sc16is7xx_port_irq, both
of which can call sc16is7xx_handle_tx.
An earlier patch added efr_lock, a mutex that controls access to the
EFR register. This mutex is already claimed in the IRQ handler, and
all that is required is to claim the same mutex in sc16is7xx_tx_proc.
See: https://github.com/raspberrypi/linux/issues/4885
Fixes: 6393ff1c44 ("sc16is7xx: Use threaded IRQ")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
Link: https://lore.kernel.org/r/20220216160802.1026013-1-phil@raspberrypi.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the current implementation the user may open a virtual tty which then
could fail to establish the underlying DLCI. The function gsmtty_open()
gets stuck in tty_port_block_til_ready() while waiting for a carrier rise.
This happens if the remote side fails to acknowledge the link establishment
request in time or completely. At some point gsm_dlci_close() is called
to abort the link establishment attempt. The function tries to inform the
associated virtual tty by performing a hangup. But the blocking loop within
tty_port_block_til_ready() is not informed about this event.
The patch proposed here fixes this by resetting the initialization state of
the virtual tty to ensure the loop exits and triggering it to make
tty_port_block_til_ready() return.
Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220218073123.2121-7-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function gsm_process_modem() exists to handle modem status bits of
incoming frames. This includes incoming MSC (modem status command) frames
and convergence layer type 2 data frames. The function, however, was only
designed to handle MSC frames as it expects the command length. Within
gsm_dlci_data() it is wrongly assumed that this is the same as the data
frame length. This is only true if the data frame contains only 1 byte of
payload.
This patch names the length parameter of gsm_process_modem() in a generic
manner to reflect its association. It also corrects all calls to the
function to handle the variable number of modem status octets correctly in
both cases.
Fixes: 7263287af9 ("tty: n_gsm: Fixed logic to decode break signal from modem status")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220218073123.2121-6-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty flow control is handled via gsmtty_throttle() and gsmtty_unthrottle().
Both functions propagate the outgoing hardware flow control state to the
remote side via MSC (modem status command) frames. The local state is taken
from the RTS (ready to send) flag of the tty. However, RTS gets mapped to
DTR (data terminal ready), which is wrong.
This patch corrects this by mapping RTS to RTS.
Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220218073123.2121-5-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The here fixed commit made the tty hangup asynchronous to avoid a circular
locking warning. I could not reproduce this warning. Furthermore, due to
the asynchronous hangup the function call now gets queued up while the
underlying tty is being freed. Depending on the timing this results in a
NULL pointer access in the global work queue scheduler. To be precise in
process_one_work(). Therefore, the previous commit made the issue worse
which it tried to fix.
This patch fixes this by falling back to the old behavior which uses a
blocking tty hangup call before freeing up the associated tty.
Fixes: 7030082a74 ("tty: n_gsm: avoid recursive locking with async port hangup")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220218073123.2121-4-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Trying to open a DLCI by sending a SABM frame may fail with a timeout.
The link is closed on the initiator side without informing the responder
about this event. The responder assumes the link is open after sending a
UA frame to answer the SABM frame. The link gets stuck in a half open
state.
This patch fixes this by initiating the proper link termination procedure
after link setup timeout instead of silently closing it down.
Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220218073123.2121-3-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.2.1.2 describes the encoding of the
C/R (command/response) bit. Table 1 shows that the actual encoding of the
C/R bit is inverted if the associated frame is sent by the responder.
The referenced commit fixed here further broke the internal meaning of this
bit in the outgoing path by always setting the C/R bit regardless of the
frame type.
This patch fixes both by setting the C/R bit always consistently for
command (1) and response (0) frames and inverting it later for the
responder where necessary. The meaning of this bit in the debug output
is being preserved and shows the bit as if it was encoded by the initiator.
This reflects only the frame type rather than the encoded combination of
communication side and frame type.
Fixes: cc0f42122a ("tty: n_gsm: Modify CR,PF bit when config requester")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220218073123.2121-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.6.3.7 describes the encoding of the
control signal octet used by the MSC (modem status command). The same
encoding is also used in convergence layer type 2 as described in chapter
5.5.2. Table 7 and 24 both require the DV (data valid) bit to be set 1 for
outgoing control signal octets sent by the DTE (data terminal equipment),
i.e. for the initiator side.
Currently, the DV bit is only set if CD (carrier detect) is on, regardless
of the side.
This patch fixes this behavior by setting the DV bit on the initiator side
unconditionally.
Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220218073123.2121-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 54da3e381c ("serial: 8250_aspeed_vuart: use UPF_IOREMAP to
set up register mapping") fixed a bug that had, as a side-effect,
prevented the 8250_aspeed_vuart driver from enabling the VUART's
FIFOs. However, fixing that (and hence enabling the FIFOs) has in
turn revealed what appears to be a hardware bug in the ASPEED VUART in
which the host-side THRE bit doesn't get if the BMC-side receive FIFO
trigger level is set to anything but one byte. This causes problems
for polled-mode writes from the host -- for example, Linux kernel
console writes proceed at a glacial pace (less than 100 bytes per
second) because the write path waits for a 10ms timeout to expire
after every character instead of being able to continue on to the next
character upon seeing THRE asserted. (GRUB behaves similarly.)
As a workaround, introduce a new port type for the ASPEED VUART that's
identical to PORT_16550A as it had previously been using, but with
UART_FCR_R_TRIG_00 instead to set the receive FIFO trigger level to
one byte, which (experimentally) seems to avoid the problematic THRE
behavior.
Fixes: 54da3e381c ("serial: 8250_aspeed_vuart: use UPF_IOREMAP to set up register mapping")
Tested-by: Konstantin Aladyshev <aladyshev22@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Link: https://lore.kernel.org/r/20220211004203.14915-1-zev@bewilderbeest.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All supported platforms by this driver require ->setup() and ->exit().
Remove unneeded test for ->setup() presence.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220215101111.47250-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since PCI core provides a generic PCI_DEVICE_DATA() macro,
replace MID_DEVICE() with former one.
No functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220215104126.7220-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add early console support which relies on the bootloader for the
initialization of the UART.
Please note, that the compatibles are taken from at91-usart MFD
driver.
Tested-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20220217094620.1148571-1-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Daniel Gibson reports that the n_tty code gets line termination wrong in
very specific cases:
"If you feed a line with exactly 64 chars + terminating newline, and
directly afterwards (without reading) another line into a pseudo
terminal, the the first read() on the other side will return the 64
char line *without* terminating newline, and the next read() will
return the missing terminating newline AND the complete next line (if
it fits in the buffer)"
and bisected the behavior to commit 3b830a9c34 ("tty: convert
tty_ldisc_ops 'read()' function to take a kernel pointer").
Now, digging deeper, it turns out that the behavior isn't exactly new:
what changed in commit 3b830a9c34 was that the tty line discipline
.read() function is now passed an intermediate kernel buffer rather than
the final user space buffer.
And that intermediate kernel buffer is 64 bytes in size - thus that
special case with exactly 64 bytes plus terminating newline.
The same problem did exist before, but historically the boundary was not
the 64-byte chunk, but the user-supplied buffer size, which is obviously
generally bigger (and potentially bigger than N_TTY_BUF_SIZE, which
would hide the issue entirely).
The reason is that the n_tty canon_copy_from_read_buf() code would look
ahead for the EOL character one byte further than it would actually
copy. It would then decide that it had found the terminator, and unmark
it as an EOL character - which in turn explains why the next read
wouldn't then be terminated by it.
Now, the reason it did all this in the first place is related to some
historical and pretty obscure EOF behavior, see commit ac8f3bf883
("n_tty: Fix poll() after buffer-limited eof push read") and commit
40d5e0905a ("n_tty: Fix EOF push handling").
And the reason for the EOL confusion is that we treat EOF as a special
EOL condition, with the EOL character being NUL (aka "__DISABLED_CHAR"
in the kernel sources).
So that EOF look-ahead also affects the normal EOL handling.
This patch just removes the look-ahead that causes problems, because EOL
is much more critical than the historical "EOF in the middle of a line
that coincides with the end of the buffer" handling ever was.
Now, it is possible that we should indeed re-introduce the "look at next
character to see if it's a EOF" behavior, but if so, that should be done
not at the kernel buffer chunk boundary in canon_copy_from_read_buf(),
but at a higher level, when we run out of the user buffer.
In particular, the place to do that would be at the top of
'n_tty_read()', where we check if it's a continuation of a previously
started read, and there is no more buffer space left, we could decide to
just eat the __DISABLED_CHAR at that point.
But that would be a separate patch, because I suspect nobody actually
cares, and I'd like to get a report about it before bothering.
Fixes: 3b830a9c34 ("tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer")
Fixes: ac8f3bf883 ("n_tty: Fix poll() after buffer-limited eof push read")
Fixes: 40d5e0905a ("n_tty: Fix EOF push handling")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215611
Reported-and-tested-by: Daniel Gibson <metalcaedes@gmail.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Fix miscompilations when function calls are made from inside a
put_user() call
- Drop __init from map_pages() declaration to avoid random boot crashes
- Added #error messages if a 64-bit compiler was used to build a 32-bit
kernel (and vice versa)
- Fix out-of-bound data TLB miss faults in sba_iommu and ccio-dma
drivers
- Add ioread64_lo_hi() and iowrite64_lo_hi() functions to avoid kernel
test robot errors
- Fix link failure when 8250_gsc driver is built without CONFIG_IOSAPIC
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Merge tag 'for-5.17/parisc-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc architecture fixes from Helge Deller:
- Fix miscompilations when function calls are made from inside a
put_user() call
- Drop __init from map_pages() declaration to avoid random boot crashes
- Added #error messages if a 64-bit compiler was used to build a 32-bit
kernel (and vice versa)
- Fix out-of-bound data TLB miss faults in sba_iommu and ccio-dma
drivers
- Add ioread64_lo_hi() and iowrite64_lo_hi() functions to avoid kernel
test robot errors
- Fix link failure when 8250_gsc driver is built without CONFIG_IOSAPIC
* tag 'for-5.17/parisc-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
serial: parisc: GSC: fix build when IOSAPIC is not set
parisc: Fix some apparent put_user() failures
parisc: Show error if wrong 32/64-bit compiler is being used
parisc: Add ioread64_lo_hi() and iowrite64_lo_hi()
parisc: Fix sglist access in ccio-dma.c
parisc: Fix data TLB miss in sba_unmap_sg
parisc: Drop __init from map_pages declaration
There is a build error when using a kernel .config file from
'kernel test robot' for a different build problem:
hppa64-linux-ld: drivers/tty/serial/8250/8250_gsc.o: in function `.LC3':
(.data.rel.ro+0x18): undefined reference to `iosapic_serial_irq'
when:
CONFIG_GSC=y
CONFIG_SERIO_GSCPS2=y
CONFIG_SERIAL_8250_GSC=y
CONFIG_PCI is not set
and hence PCI_LBA is not set.
IOSAPIC depends on PCI_LBA, so IOSAPIC is not set/enabled.
Make the use of iosapic_serial_irq() conditional to fix the build error.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-serial@vger.kernel.org
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Johan Hovold <johan@kernel.org>
Suggested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
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Merge 5.17-rc4 into tty-next
We need the tty/serial fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Right now, even when `delay_rts_before_send` and `delay_rts_after_send`
are 0, the hrtimer is triggered (with timeout 0) which can introduce a
few 100us of additional overhead on slower i.MX platforms.
Implement a fast path when the delays are 0, where the RTS signal is
toggled immediately instead of going through an hrtimer. This fast path
behaves identical to the code before delay support was implemented.
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Harald Seiler <hws@denx.de>
Link: https://lore.kernel.org/r/20220119145204.238767-1-hws@denx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add ACPI support to 8250_bcm2835aux driver. This makes it possible to
use the miniuart on the Raspberry Pi with the tianocore/edk2 UEFI
firmware.
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Adrien Thierry <athierry@redhat.com>
Link: https://lore.kernel.org/r/20220207232129.402882-1-athierry@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Enable mctrl_gpio wake_irq if device_may_wakeup when usart is suspended,
and disable mctrl_gpios wake_irq if device_may_wakeup when usart is
resumed.
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20220203171644.12231-3-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a new API to enable / disable wake_irq in order to enable gpio irqs as
wakeup irqs for the uart port.
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20220203171644.12231-2-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The free_page(addr), which becomes free_pages(addr, 0) checks addr
against 0. No need to repeat this check in the callers.
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220204152808.10808-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
