The serial info sometimes produces negative TX/RX counts. E.g.:
3: uart:FSL_LPUART mmio:0x02970000 irq:46 tx:-1595870545 rx:339619
RTS|CTS|DTR|DSR|CD
It appears that the print format specifiers don't match with the types of
the respective variables. E.g.: All of the fields in struct uart_icount
are u32, but the format specifier used is %d, even though u32 is unsigned
and %d is for signed integers. Update drivers/tty/serial/serial_core.c
to use the proper format specifiers. Reference
https://docs.kernel.org/core-api/printk-formats.html as the documentation
for what format specifiers are the proper ones to use for a given C type.
Signed-off-by: Joseph Tilahun <jtilahun@astranis.com>
Link: https://lore.kernel.org/r/20250610065653.3750067-1-jtilahun@astranis.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This code (tty_get -> vhangup -> tty_put) is repeated on few places.
Introduce a helper similar to tty_port_tty_hangup() (asynchronous) to
handle even vhangup (synchronous).
And use it on those places.
In fact, reuse the tty_port_tty_hangup()'s code and call tty_vhangup()
depending on a new bool parameter.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: David Lin <dtwlin@gmail.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: Oliver Neukum <oneukum@suse.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20250611100319.186924-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_get_icount() and uart_carrier_raised() open code
uart_port_ref_lock(). Use the helper instead.
The difference is we use _irqsave() variants of a spinlock now. But
that's "safer" than _irq().
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250425111315.1036184-6-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_port_lock() and uart_port_unlock() are (at the same time) defined
as:
* functions in include/linux/serial_core.h
* macros in drivers/tty/serial/serial_core.c
The former are sane uart port lock wrappers.
The latter _lock() does something completely different: it inspects
a uart_state, obtains a uart_port from it, and increases its reference
count. And if that all succeeded, the port is locked too.
Similarly, the _unlock() counterpart first unlocks and then decrements
the refcount too.
This state is REALLY CONFUSING.
So rename the latter (local .c macros):
* uart_port_lock() -> uart_port_ref_lock(), and
* uart_port_unlock() -> uart_port_unlock_deref().
Now, the forbidden while-at-it part: convert from a macro to an inline
-- do it here as the passed 'flags' have to be pointer to ulong now. So
we avoid doubled changes on identical LOCs.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250425111315.1036184-5-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The inline-defined constants look weird. Instead, define a proper enum
for them and type uart_port::iotype as that enum. This allows for proper
checking in switch-case labels (somewhere, a default or UPIO_UNKNOWN
label needs to be added/handled).
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250425111315.1036184-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here is the big set of serial and tty driver updates for 6.15-rc1.
Include in here are the following:
- more great tty layer cleanups from Jiri. Someday this will be done,
but that's not going to be any year soon...
- kdb debug driver reverts to fix a reported issue
- lots of .dts binding updates for different devices with serial
devices
- lots of tiny updates and tweaks and a few bugfixes for different
serial drivers.
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-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here is the big set of serial and tty driver updates for 6.15-rc1.
Include in here are the following:
- more great tty layer cleanups from Jiri. Someday this will be done,
but that's not going to be any year soon...
- kdb debug driver reverts to fix a reported issue
- lots of .dts binding updates for different devices with serial
devices
- lots of tiny updates and tweaks and a few bugfixes for different
serial drivers.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (79 commits)
tty: serial: fsl_lpuart: Fix unused variable 'sport' build warning
serial: stm32: do not deassert RS485 RTS GPIO prematurely
serial: 8250: add driver for NI UARTs
dt-bindings: serial: snps-dw-apb-uart: document RZ/N1 binding without DMA
serial: icom: fix code format problems
serial: sh-sci: Save and restore more registers
tty: serial: pl011: remove incorrect of_match_ptr annotation
dt-bindings: serial: snps-dw-apb-uart: Add support for rk3562
tty: serial: lpuart: only disable CTS instead of overwriting the whole UARTMODIR register
tty: caif: removed unused function debugfs_tx()
serial: 8250_dma: terminate correct DMA in tx_dma_flush()
tty: serial: fsl_lpuart: rename register variables more specifically
tty: serial: fsl_lpuart: use port struct directly to simply code
tty: serial: fsl_lpuart: Use u32 and u8 for register variables
tty: serial: fsl_lpuart: disable transmitter before changing RS485 related registers
tty: serial: 8250: Add Brainboxes XC devices
dt-bindings: serial: fsl-lpuart: support i.MX94
tty: serial: 8250: Add some more device IDs
dt-bindings: serial: samsung: add exynos7870-uart compatible
serial: 8250_dw: Comment possible corner cases in serial_out() implementation
...
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Merge tag 'printk-for-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- New option "printk.debug_non_panic_cpus" allows to store printk
messages from non-panic CPUs during panic. It might be useful when
panic() fails. It is disabled by default because it increases the
chance to see the messages printed before panic() and on the
panic-CPU.
- New build option "CONFIG_NULL_TTY_DEFAULT_CONSOLE" allows to build
kernel without the virtual terminal support which prefers ttynull
over serial console.
- Do not unblank suspended consoles.
- Some code clean up.
* tag 'printk-for-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk/panic: Add option to allow non-panic CPUs to write to the ring buffer.
printk: Add an option to allow ttynull to be a default console device
printk: Check CON_SUSPEND when unblanking a console
printk: Rename console_start to console_resume
printk: Rename console_stop to console_suspend
printk: Rename resume_console to console_resume_all
printk: Rename suspend_console to console_suspend_all
change_irq and change_port are boolean variables. Mark them as such
(instead of uint).
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250317070046.24386-32-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_line_info() wants to work with struct uart_state. Do not pass a
driver and an index. Pass the precomputed struct directly.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250317070046.24386-27-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The linking is done implicitly by tty_port_register_device_attr_serdev()
few lines below. So drop this explicit tty_port_link_device().
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250317070046.24386-26-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The intent of console_start was to resume a previously suspended console,
so rename it accordingly.
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20250226-printk-renaming-v1-4-0b878577f2e6@suse.com
[pmladek@suse.com: Fixed typo in the commit message. Updated also new drm_log.c.]
Signed-off-by: Petr Mladek <pmladek@suse.com>
The intent of console_stop was in fact to suspend it, so rename the
function accordingly.
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20250226-printk-renaming-v1-3-0b878577f2e6@suse.com
[pmladek@suse.com: Fixed typo in the commit message. Updated also new drm_log.c]
Signed-off-by: Petr Mladek <pmladek@suse.com>
Here is the big set of driver core and debugfs updates for 6.14-rc1.
It's coming late in the merge cycle as there are a number of merge
conflicts with your tree now, and I wanted to make sure they were
working properly. To resolve them, look in linux-next, and I will send
the "fixup" patch as a response to the pull request.
Included in here is a bunch of driver core, PCI, OF, and platform rust
bindings (all acked by the different subsystem maintainers), hence the
merge conflict with the rust tree, and some driver core api updates to
mark things as const, which will also require some fixups due to new
stuff coming in through other trees in this merge window.
There are also a bunch of debugfs updates from Al, and there is at least
one user that does have a regression with these, but Al is working on
tracking down the fix for it. In my use (and everyone else's linux-next
use), it does not seem like a big issue at the moment.
Here's a short list of the things in here:
- driver core bindings for PCI, platform, OF, and some i/o functions.
We are almost at the "write a real driver in rust" stage now,
depending on what you want to do.
- misc device rust bindings and a sample driver to show how to use
them
- debugfs cleanups in the fs as well as the users of the fs api for
places where drivers got it wrong or were unnecessarily doing things
in complex ways.
- driver core const work, making more of the api take const * for
different parameters to make the rust bindings easier overall.
- other small fixes and updates
All of these have been in linux-next with all of the aforementioned
merge conflicts, and the one debugfs issue, which looks to be resolved
"soon".
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core and debugfs updates from Greg KH:
"Here is the big set of driver core and debugfs updates for 6.14-rc1.
Included in here is a bunch of driver core, PCI, OF, and platform rust
bindings (all acked by the different subsystem maintainers), hence the
merge conflict with the rust tree, and some driver core api updates to
mark things as const, which will also require some fixups due to new
stuff coming in through other trees in this merge window.
There are also a bunch of debugfs updates from Al, and there is at
least one user that does have a regression with these, but Al is
working on tracking down the fix for it. In my use (and everyone
else's linux-next use), it does not seem like a big issue at the
moment.
Here's a short list of the things in here:
- driver core rust bindings for PCI, platform, OF, and some i/o
functions.
We are almost at the "write a real driver in rust" stage now,
depending on what you want to do.
- misc device rust bindings and a sample driver to show how to use
them
- debugfs cleanups in the fs as well as the users of the fs api for
places where drivers got it wrong or were unnecessarily doing
things in complex ways.
- driver core const work, making more of the api take const * for
different parameters to make the rust bindings easier overall.
- other small fixes and updates
All of these have been in linux-next with all of the aforementioned
merge conflicts, and the one debugfs issue, which looks to be resolved
"soon""
* tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (95 commits)
rust: device: Use as_char_ptr() to avoid explicit cast
rust: device: Replace CString with CStr in property_present()
devcoredump: Constify 'struct bin_attribute'
devcoredump: Define 'struct bin_attribute' through macro
rust: device: Add property_present()
saner replacement for debugfs_rename()
orangefs-debugfs: don't mess with ->d_name
octeontx2: don't mess with ->d_parent or ->d_parent->d_name
arm_scmi: don't mess with ->d_parent->d_name
slub: don't mess with ->d_name
sof-client-ipc-flood-test: don't mess with ->d_name
qat: don't mess with ->d_name
xhci: don't mess with ->d_iname
mtu3: don't mess wiht ->d_iname
greybus/camera - stop messing with ->d_iname
mediatek: stop messing with ->d_iname
netdevsim: don't embed file_operations into your structs
b43legacy: make use of debugfs_get_aux()
b43: stop embedding struct file_operations into their objects
carl9170: stop embedding file_operations into their objects
...
Constify the following API:
struct device *device_find_child(struct device *dev, void *data,
int (*match)(struct device *dev, void *data));
To :
struct device *device_find_child(struct device *dev, const void *data,
device_match_t match);
typedef int (*device_match_t)(struct device *dev, const void *data);
with the following reasons:
- Protect caller's match data @*data which is for comparison and lookup
and the API does not actually need to modify @*data.
- Make the API's parameters (@match)() and @data have the same type as
all of other device finding APIs (bus|class|driver)_find_device().
- All kinds of existing device match functions can be directly taken
as the API's argument, they were exported by driver core.
Constify the API and adapt for various existing usages.
BTW, various subsystem changes are squashed into this commit to meet
'git bisect' requirement, and this commit has the minimal and simplest
changes to complement squashing shortcoming, and that may bring extra
code improvement.
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Uwe Kleine-König <ukleinek@kernel.org> # for drivers/pwm
Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20241224-const_dfc_done-v5-4-6623037414d4@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This "change_port" part of uart_set_info() is for no good reason
inlined there. It makes the function rather hard to read. Therefore,
extract it to a separate function.
This allows for flattening the ifs (with short path "return"s) and
avoiding two levels of indentation. Both making the code really flat and
comprehesible.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20241211074933.92973-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The label is unneeded since 7ba2e76982 (tty: Split the serial_core
helpers for setserial into two). Until then, there was a lock held in
uart_set_info().
Now it is not, so we can remove the label. This involves reordering the
code, so that it is clear what values are returned, where and why. Until
now, it was really hard to follow.
The "change_port" part of the function is extracted into a separate
function in the next patch. This patch makes the transition there easier
too.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20241211074933.92973-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Simplify 4 more functions using guard(mutex): uart_get_info(),
console_store(), serial_core_add_one_port(), and
serial_core_register_port(). Especially console_store() is now much less
convoluted. In the others, we save some goto-s and even local variables
are dropped in some.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20241211074933.92973-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the irq_get_nr_irqs() function instead of the global variable
'nr_irqs'. Prepare for changing 'nr_irqs' from an exported global
variable into a variable with file scope.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20241015190953.1266194-13-bvanassche@acm.org
Here is the "big" set of tty/serial driver updates for 6.12-rc1.
Nothing major in here, just nice forward progress in the slow cleanup of
the serial apis, and lots of other driver updates and fixes.
Included in here are:
- serial api updates from Jiri to make things more uniform and sane
- 8250_platform driver cleanups
- samsung serial driver fixes and updates
- qcom-geni serial driver fixes from Johan for the bizarre UART engine
that that chip seems to have. Hopefully it's in a better state now,
but hardware designers still seem to come up with more ways to make
broken UARTS 40+ years after this all should have finished.
- sc16is7xx driver updates
- omap 8250 driver updates
- 8250_bcm2835aux driver updates
- a few new serial driver bindings added
- other serial minor driver updates
All of these have been in linux-next for a long time with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty / serial driver updates from Greg KH:
"Here is the "big" set of tty/serial driver updates for 6.12-rc1.
Nothing major in here, just nice forward progress in the slow cleanup
of the serial apis, and lots of other driver updates and fixes.
Included in here are:
- serial api updates from Jiri to make things more uniform and sane
- 8250_platform driver cleanups
- samsung serial driver fixes and updates
- qcom-geni serial driver fixes from Johan for the bizarre UART
engine that that chip seems to have. Hopefully it's in a better
state now, but hardware designers still seem to come up with more
ways to make broken UARTS 40+ years after this all should have
finished.
- sc16is7xx driver updates
- omap 8250 driver updates
- 8250_bcm2835aux driver updates
- a few new serial driver bindings added
- other serial minor driver updates
All of these have been in linux-next for a long time with no reported
problems"
* tag 'tty-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (65 commits)
tty: serial: samsung: Fix serial rx on Apple A7-A9
tty: serial: samsung: Fix A7-A11 serial earlycon SError
tty: serial: samsung: Use bit manipulation macros for APPLE_S5L_*
tty: rp2: Fix reset with non forgiving PCIe host bridges
serial: 8250_aspeed_vuart: Enable module autoloading
serial: qcom-geni: fix polled console corruption
serial: qcom-geni: disable interrupts during console writes
serial: qcom-geni: fix console corruption
serial: qcom-geni: introduce qcom_geni_serial_poll_bitfield()
serial: qcom-geni: fix arg types for qcom_geni_serial_poll_bit()
soc: qcom: geni-se: add GP_LENGTH/IRQ_EN_SET/IRQ_EN_CLEAR registers
serial: qcom-geni: fix false console tx restart
serial: qcom-geni: fix fifo polling timeout
tty: hvc: convert comma to semicolon
mxser: convert comma to semicolon
serial: 8250_bcm2835aux: Fix clock imbalance in PM resume
serial: sc16is7xx: convert bitmask definitions to use BIT() macro
serial: sc16is7xx: fix copy-paste errors in EFR_SWFLOWx_BIT constants
serial: sc16is7xx: remove SC16IS7XX_MSR_DELTA_MASK
serial: xilinx_uartps: Make cdns_rs485_supported static
...
Introduce uart_port_set_cons() as a wrapper to set @cons of a
uart_port. The wrapper sets @cons under the port lock in order
to prevent @cons from disappearing while another context is
holding the port lock. This is necessary for a follow-up
commit relating to the port lock wrappers, which rely on @cons
not changing between lock and unlock.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Tested-by: Théo Lebrun <theo.lebrun@bootlin.com> # EyeQ5, AMBA-PL011
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240820063001.36405-12-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
Guards can help to make the code more readable. So use it wherever they
do so.
On many places labels and 'ret' locals are eliminated completely.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240808103549.429349-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Coverity reports (as CID 1536978) that uart_poll_init() passes
uninitialized pm_state to uart_change_pm(). It is in case the first 'if'
takes the true branch (does "goto out;").
Fix this and simplify the function by simple guard(mutex). The code
needs no labels after this at all. And it is pretty clear that the code
has not fiddled with pm_state at that point.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Fixes: 5e227ef2aa (serial: uart_poll_init() should power on the UART)
Cc: stable@vger.kernel.org
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20240805102046.307511-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit af224ca2df (serial: core: Prevent unsafe uart port access, part
3) added few uport == NULL checks. It added one to uart_shutdown(), so
the commit assumes, uport can be NULL in there. But right after that
protection, there is an unprotected "uart_port_dtr_rts(uport, false);"
call. That is invoked only if HUPCL is set, so I assume that is the
reason why we do not see lots of these reports.
Or it cannot be NULL at this point at all for some reason :P.
Until the above is investigated, stay on the safe side and move this
dereference to the if too.
I got this inconsistency from Coverity under CID 1585130. Thanks.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240805102046.307511-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Calling ioctl TIOCSSERIAL with an invalid baud_base can
result in uartclk being zero, which will result in a
divide by zero error in uart_get_divisor(). The check for
uartclk being zero in uart_set_info() needs to be done
before other settings are made as subsequent calls to
ioctl TIOCSSERIAL for the same port would be impacted if
the uartclk check was done where uartclk gets set.
Oops: divide error: 0000 PREEMPT SMP KASAN PTI
RIP: 0010:uart_get_divisor (drivers/tty/serial/serial_core.c:580)
Call Trace:
<TASK>
serial8250_get_divisor (drivers/tty/serial/8250/8250_port.c:2576
drivers/tty/serial/8250/8250_port.c:2589)
serial8250_do_set_termios (drivers/tty/serial/8250/8250_port.c:502
drivers/tty/serial/8250/8250_port.c:2741)
serial8250_set_termios (drivers/tty/serial/8250/8250_port.c:2862)
uart_change_line_settings (./include/linux/spinlock.h:376
./include/linux/serial_core.h:608 drivers/tty/serial/serial_core.c:222)
uart_port_startup (drivers/tty/serial/serial_core.c:342)
uart_startup (drivers/tty/serial/serial_core.c:368)
uart_set_info (drivers/tty/serial/serial_core.c:1034)
uart_set_info_user (drivers/tty/serial/serial_core.c:1059)
tty_set_serial (drivers/tty/tty_io.c:2637)
tty_ioctl (drivers/tty/tty_io.c:2647 drivers/tty/tty_io.c:2791)
__x64_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:907
fs/ioctl.c:893 fs/ioctl.c:893)
do_syscall_64 (arch/x86/entry/common.c:52
(discriminator 1) arch/x86/entry/common.c:83 (discriminator 1))
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
Reported-by: syzkaller <syzkaller@googlegroups.com>
Cc: stable@vger.kernel.org
Signed-off-by: George Kennedy <george.kennedy@oracle.com>
Rule: add
Link: https://lore.kernel.org/stable/1721148848-9784-1-git-send-email-george.kennedy%40oracle.com
Link: https://lore.kernel.org/r/1721219078-3209-1-git-send-email-george.kennedy@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Let's add serial_base_match_and_update_preferred_console() for consoles
using DEVNAME:0.0 style naming.
The earlier approach to add it caused issues in the kernel command line
ordering as we were calling __add_preferred_console() again for the
deferred consoles.
Signed-off-by: Tony Lindgren <tony.lindgren@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240703100615.118762-3-tony.lindgren@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 787a1cabac.
Let's roll back all of the serial core and printk console changes that
went into 6.10-rc1 as there still are problems with them that need to be
sorted out.
Link: https://lore.kernel.org/r/ZnpRozsdw6zbjqze@tlindgre-MOBL1
Reported-by: Petr Mladek <pmladek@suse.com>
Reported-by: Tony Lindgren <tony@atomide.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a serdev_device_driver is already loaded for a serdev_tty_port when it
gets registered by tty_port_register_device_attr_serdev() then that
driver's probe() method will be called immediately.
The serdev_device_driver's probe() method should then be able to call
serdev_device_open() successfully, but because UPF_DEAD is still dead
serdev_device_open() will fail with -ENXIO in this scenario:
serdev_device_open()
ctrl->ops->open() /* this callback being ttyport_open() */
tty->ops->open() /* this callback being uart_open() */
tty_port_open()
port->ops->activate() /* this callback being uart_port_activate() */
Find bit UPF_DEAD is set in uport->flags and fail with errno -ENXIO.
Fix this be clearing UPF_DEAD before tty_port_register_device_attr_serdev()
note this only moves up the UPD_DEAD clearing a small bit, before:
tty_port_register_device_attr_serdev();
mutex_unlock(&tty_port.mutex);
uart_port.flags &= ~UPF_DEAD;
mutex_unlock(&port_mutex);
after:
uart_port.flags &= ~UPF_DEAD;
tty_port_register_device_attr_serdev();
mutex_unlock(&tty_port.mutex);
mutex_unlock(&port_mutex);
Reported-by: Weifeng Liu <weifeng.liu.z@gmail.com>
Closes: https://lore.kernel.org/platform-driver-x86/20240505130800.2546640-1-weifeng.liu.z@gmail.com/
Tested-by: Weifeng Liu <weifeng.liu.z@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20240509141549.63704-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case the UART port is used as a console, no_console_suspend is
available in bootargs and UART port is part of a software-controlled power
domain we need to call device_set_awake_path(). This lets the power
domain core code know that this domain should not be powered off
during system suspend. Otherwise, the UART port power domain is turned off,
nothing is printed while suspending and the suspend/resume process is
blocked. This was detected on the Renesas RZ/G3S SoC while adding support
for power domains.
Based on code investigation (on v6.9-rc5), this issue is present on other
SoCs (e.g., Renesas R-Mobile A1 [1], IMX8QXP [2]) and different SoCs have
particular implementation to handle it. Due to this the patch added the
call of device_set_awake_path() in uart_suspend_port() instead of having
it in the platform specific UART driver.
[1] drivers/pmdomain/renesas/rmobile-sysc.c:116
[2] drivers/pmdomain/imx/scu-pd.c:357
Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Tony Lindgren <tony.lindgren@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Link: https://lore.kernel.org/r/20240430095930.2806067-1-claudiu.beznea.uj@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We want the tty fixes in here as well, and it resolves a merge conflict
in:
drivers/tty/serial/serial_core.c
as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After conversion to the kfifo, it becomes possible to extract two helper
functions for better maintenance and code deduplication. Do it here.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240409174057.1104262-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pengfei Xu reports, that the -next commit 1788cf6a91 (tty: serial:
switch from circ_buf to kfifo) tries to emit a WARNING and that leads to
lockdep errors. Obviously we cannot print anything from uart_put_char()!
This WARN_ON_ONCE() was/is a debug aid to check if the condition in
uart_put_char() can happen at all. Pengfei Xu confirmed it can. Unlike
me and kbuild bot in my queue.
Second, I completely forgot about it, so I did not remove it in the
final version, nor mentioned it in the commit log.
Drop it now as we are all good. And we even have stack traces (and a
reproducer)!
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Reported-by: Pengfei Xu <pengfei.xu@intel.com>
Link: https://lore.kernel.org/r/20240416071904.21440-1-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We are seeing start_tx being called after port shutdown as noted by Jiri.
This happens because we are missing the startup and shutdown related
functions for the serial base port.
Let's fix the issue by adding startup and shutdown functions for the
serial base port to block tx flushing for the serial base port when the
port is not in use.
Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Cc: stable <stable@kernel.org>
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20240411055848.38190-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The circular buffer is NULLified in uart_tty_port_shutdown()
under the spin lock. However, the PM or other timer based callbacks
may still trigger after this event without knowning that buffer pointer
is not valid. Since the serial code is a bit inconsistent in checking
the buffer state (some rely on the head-tail positions, some on the
buffer pointer), it's better to have both aligned, i.e. buffer pointer
to be NULL and head-tail possitions to be the same, meaning it's empty.
This will prevent asynchronous calls to dereference NULL pointer as
reported recently in 8250 case:
BUG: kernel NULL pointer dereference, address: 00000cf5
Workqueue: pm pm_runtime_work
EIP: serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809)
...
? serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809)
__start_tx (drivers/tty/serial/8250/8250_port.c:1551)
serial8250_start_tx (drivers/tty/serial/8250/8250_port.c:1654)
serial_port_runtime_suspend (include/linux/serial_core.h:667 drivers/tty/serial/serial_port.c:63)
__rpm_callback (drivers/base/power/runtime.c:393)
? serial_port_remove (drivers/tty/serial/serial_port.c:50)
rpm_suspend (drivers/base/power/runtime.c:447)
The proposed change will prevent ->start_tx() to be called during
suspend on shut down port.
Fixes: 43066e3222 ("serial: port: Don't suspend if the port is still busy")
Cc: stable <stable@kernel.org>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202404031607.2e92eebe-lkp@intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240404150034.41648-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 45a3a8ef81 ("serial: core: Revert checks for tx runtime PM state")
caused a regression for Sun Ultra 60 for the sunsab driver as reported by
Nick Bowler <nbowler@draconx.ca>.
We need to add back the check runtime PM enabled state for serial port
controller device, I wrongly assumed earlier we could just remove it.
Fixes: 45a3a8ef81 ("serial: core: Revert checks for tx runtime PM state")
Cc: stable <stable@kernel.org>
Reported-by: Nick Bowler <nbowler@draconx.ca>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20240325071649.27040-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We can now add hardware based addressing for serial ports. Starting with
commit 84a9582fd2 ("serial: core: Start managing serial controllers to
enable runtime PM"), and all the related fixes to this commit, the serial
core now knows to which serial port controller the ports are connected.
The serial ports can be addressed with DEVNAME:0.0 style naming. The names
are something like 00:04:0.0 for a serial port on qemu, and something like
2800000.serial:0.0 on platform device using systems like ARM64 for example.
The DEVNAME is the unique serial port hardware controller device name, AKA
the name for port->dev. The 0.0 are the serial core controller id and port
id.
Typically 0.0 are used for each controller and port instance unless the
serial port hardware controller has multiple controllers or ports.
Using DEVNAME:0.0 style naming actually solves two long term issues for
addressing the serial ports:
1. According to Andy Shevchenko, using DEVNAME:0.0 style naming fixes an
issue where depending on the BIOS settings, the kernel serial port ttyS
instance number may change if HSUART is enabled
2. Device tree using architectures no longer necessarily need to specify
aliases to find a specific serial port, and we can just allocate the
ttyS instance numbers dynamically in whatever probe order
To do this, let's match the hardware addressing style console name to
the character device name used, and add a preferred console using the
character device name.
Note that when using console=DEVNAME:0.0 style kernel command line, the
8250 serial console gets enabled later compared to using console=ttyS
naming for ISA ports. This is because the serial port DEVNAME to character
device mapping is not known until the serial driver probe time. If used
together with earlycon, this issue is avoided.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20240327110021.59793-5-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Switch from struct circ_buf to proper kfifo. kfifo provides much better
API, esp. when wrap-around of the buffer needs to be taken into account.
Look at pl011_dma_tx_refill() or cpm_uart_tx_pump() changes for example.
Kfifo API can also fill in scatter-gather DMA structures, so it easier
for that use case too. Look at lpuart_dma_tx() for example. Note that
not all drivers can be converted to that (like atmel_serial), they
handle DMA specially.
Note that usb-serial uses kfifo for TX for ages.
omap needed a bit more care as it needs to put a char into FIFO to start
the DMA transfer when OMAP_DMA_TX_KICK is set. In that case, we have to
do kfifo_dma_out_prepare twice: once to find out the tx_size (to find
out if it is worths to do DMA at all -- size >= 4), the second time for
the actual transfer.
All traces of circ_buf are removed from serial_core.h (and its struct
uart_state).
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Al Cooper <alcooperx@gmail.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com>
Cc: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Richard Genoud <richard.genoud@gmail.com>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: Maciej W. Rozycki <macro@orcam.me.uk>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Neil Armstrong <neil.armstrong@linaro.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: Taichi Sugaya <sugaya.taichi@socionext.com>
Cc: Takao Orito <orito.takao@socionext.com>
Cc: Bjorn Andersson <andersson@kernel.org>
Cc: Konrad Dybcio <konrad.dybcio@linaro.org>
Cc: Pali Rohár <pali@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Alim Akhtar <alim.akhtar@samsung.com>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Chunyan Zhang <zhang.lyra@gmail.com>
Cc: Patrice Chotard <patrice.chotard@foss.st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Hammer Hsieh <hammerh0314@gmail.com>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Timur Tabi <timur@kernel.org>
Cc: Michal Simek <michal.simek@amd.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20240405060826.2521-13-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
During the handoff from earlycon to the real console driver, we have
two separate drivers operating on the same device concurrently. In the
case of the 8250 driver these concurrent accesses cause problems due
to the driver's use of banked registers, controlled by LCR.DLAB. It is
possible for the setup(), config_port(), pm() and set_mctrl() callbacks
to set DLAB, which can cause the earlycon code that intends to access
TX to instead access DLL, leading to missed output and corruption on
the serial line due to unintended modifications to the baud rate.
In particular, for setup() we have:
univ8250_console_setup()
-> serial8250_console_setup()
-> uart_set_options()
-> serial8250_set_termios()
-> serial8250_do_set_termios()
-> serial8250_do_set_divisor()
For config_port() we have:
serial8250_config_port()
-> autoconfig()
For pm() we have:
serial8250_pm()
-> serial8250_do_pm()
-> serial8250_set_sleep()
For set_mctrl() we have (for some devices):
serial8250_set_mctrl()
-> omap8250_set_mctrl()
-> __omap8250_set_mctrl()
To avoid such problems, let's make it so that the console is locked
during pre-registration calls to these callbacks, which will prevent
the earlycon driver from running concurrently.
Remove the partial solution to this problem in the 8250 driver
that locked the console only during autoconfig_irq(), as this would
result in a deadlock with the new approach. The console continues
to be locked during autoconfig_irq() because it can only be called
through uart_configure_port().
Although this patch introduces more locking than strictly necessary
(and in particular it also locks during the call to rs485_config()
which is not affected by this issue as far as I can tell), it follows
the principle that it is the responsibility of the generic console
code to manage the earlycon handoff by ensuring that earlycon and real
console driver code cannot run concurrently, and not the individual
drivers.
Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Link: https://linux-review.googlesource.com/id/I7cf8124dcebf8618e6b2ee543fa5b25532de55d8
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240304214350.501253-1-pcc@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In uart_tiocmget():
result = uport->mctrl;
uart_port_lock_irq(uport);
result |= uport->ops->get_mctrl(uport);
uart_port_unlock_irq(uport);
...
return result;
In uart_update_mctrl():
uart_port_lock_irqsave(port, &flags);
...
port->mctrl = (old & ~clear) | set;
...
port->ops->set_mctrl(port, port->mctrl);
...
uart_port_unlock_irqrestore(port, flags);
An atomicity violation is identified due to the concurrent execution of
uart_tiocmget() and uart_update_mctrl(). After assigning
result = uport->mctrl, the mctrl value may change in uart_update_mctrl(),
leading to a mismatch between the value returned by
uport->ops->get_mctrl(uport) and the mctrl value previously read.
This can result in uart_tiocmget() returning an incorrect value.
This possible bug is found by an experimental static analysis tool
developed by our team, BassCheck[1]. This tool analyzes the locking APIs
to extract function pairs that can be concurrently executed, and then
analyzes the instructions in the paired functions to identify possible
concurrency bugs including data races and atomicity violations. The above
possible bug is reported when our tool analyzes the source code of
Linux 5.17.
To address this issue, it is suggested to move the line
result = uport->mctrl inside the uart_port_lock block to ensure atomicity
and prevent the mctrl value from being altered during the execution of
uart_tiocmget(). With this patch applied, our tool no longer reports the
bug, with the kernel configuration allyesconfig for x86_64. Due to the
absence of the requisite hardware, we are unable to conduct runtime
testing of the patch. Therefore, our verification is solely based on code
logic analysis.
[1] https://sites.google.com/view/basscheck/
Fixes: c5f4644e6c ("[PATCH] Serial: Adjust serial locking")
Cc: stable@vger.kernel.org
Signed-off-by: Gui-Dong Han <2045gemini@gmail.com>
Link: https://lore.kernel.org/r/20240112113624.17048-1-2045gemini@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the imx driver cannot support RS485 it nullifies the ports
rs485_supported structure. But it still calls uart_get_rs485_mode() which
may set the RS485_ENABLED flag nevertheless.
This may lead to an attempt to configure RS485 even if it is not supported
when the flag is evaluated in uart_configure_port() at port startup.
Avoid this by bailing out of uart_get_rs485_mode() if the RS485_ENABLED
flag is not supported by the caller.
With this fix a check for RTS availability is now obsolete in the imx
driver, since it can not evaluate to true any more. So remove this check.
Furthermore the explicit nullifcation of rs485_supported is not needed,
since the memory has already been set to zeros at allocation. So remove
this, too.
Fixes: 00d7a00e2a ("serial: imx: Fill in rs485_supported")
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: <stable@vger.kernel.org>
Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240103061818.564-6-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some uart drivers specify a rs485_config() function and then decide later
to disable RS485 support for some reason (e.g. imx and ar933).
In these cases userspace may be able to activate RS485 via TIOCSRS485
nevertheless, since in uart_set_rs485_config() an existing rs485_config()
function indicates that RS485 is supported.
Make sure that this is not longer possible by checking the uarts
rs485_supported.flags instead and bailing out if SER_RS485_ENABLED is not
set.
Furthermore instead of returning an empty structure return -ENOTTY if the
RS485 configuration is requested via TIOCGRS485 but RS485 is not supported.
This has a small impact on userspace visibility but it is consistent with
the -ENOTTY error for TIOCGRS485.
Fixes: e849145e1f ("serial: ar933x: Fill in rs485_supported")
Fixes: 55e18c6b6d ("serial: imx: Remove serial_rs485 sanitization")
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: <stable@vger.kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Link: https://lore.kernel.org/r/20240103061818.564-5-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Among other things uart_sanitize_serial_rs485() tests the sanity of the RTS
settings in a RS485 configuration that has been passed by userspace.
If RTS-on-send and RTS-after-send are both set or unset the configuration
is adjusted and RTS-after-send is disabled and RTS-on-send enabled.
This however makes only sense if both RTS modes are actually supported by
the driver.
With commit be2e2cb1d2 ("serial: Sanitize rs485_struct") the code does
take the driver support into account but only checks if one of both RTS
modes are supported. This may lead to the errorneous result of RTS-on-send
being set even if only RTS-after-send is supported.
Fix this by changing the implemented logic: First clear all unsupported
flags in the RS485 configuration, then adjust an invalid RTS setting by
taking into account which RTS mode is supported.
Cc: <stable@vger.kernel.org>
Fixes: be2e2cb1d2 ("serial: Sanitize rs485_struct")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Link: https://lore.kernel.org/r/20240103061818.564-4-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the RS485 feature RX-during-TX is supported by means of a GPIO set the
according supported flag. Otherwise setting this feature from userspace may
not be possible, since in uart_sanitize_serial_rs485() the passed RS485
configuration is matched against the supported features and unsupported
settings are thereby removed and thus take no effect.
Cc: <stable@vger.kernel.org>
Fixes: 163f080eb7 ("serial: core: Add option to output RS485 RX_DURING_TX state via GPIO")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Link: https://lore.kernel.org/r/20240103061818.564-3-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Both the imx and stm32 driver set the rx-during-tx GPIO in rs485_config().
Since this function is called with the port lock held, this can be a
problem in case that setting the GPIO line can sleep (e.g. if a GPIO
expander is used which is connected via SPI or I2C).
Avoid this issue by moving the GPIO setting outside of the port lock into
the serial core and thus making it a generic feature.
Also with commit c54d485436 ("serial: stm32: Add support for rs485
RX_DURING_TX output GPIO") the SER_RS485_RX_DURING_TX flag is only set if a
rx-during-tx GPIO is _not_ available, which is wrong. Fix this, too.
Furthermore reset old GPIO settings in case that changing the RS485
configuration failed.
Fixes: c54d485436 ("serial: stm32: Add support for rs485 RX_DURING_TX output GPIO")
Fixes: ca530cfa96 ("serial: imx: Add support for RS485 RX_DURING_TX output GPIO")
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Link: https://lore.kernel.org/r/20240103061818.564-2-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Check if port type is not PORT_UNKNOWN during poll_init.
The kgdboc calls the tty_find_polling_driver that check
if the serial is able to use poll_init. The poll_init calls
the uart uart_poll_init that try to configure the uart with the
selected boot parameters. The uart must be ready before setting
parameters. Seems that PORT_UNKNOWN is already used by other
functions in serial_core to detect uart status, so use the same
to avoid to use it in invalid state.
The crash happen for instance in am62x architecture where the 8250
register the platform driver after the 8250 core is initialized.
Follow the report crash coming from KGDB
Thread 2 received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1]
_outb (addr=<optimized out>, value=<optimized out>) at ./include/asm-generic/io.h:584
584 __raw_writeb(value, PCI_IOBASE + addr);
(gdb) bt
This section of the code is too early because in this case
the omap serial is not probed
Thread 2 received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1]
_outb (addr=<optimized out>, value=<optimized out>) at ./include/asm-generic/io.h:584
584 __raw_writeb(value, PCI_IOBASE + addr);
(gdb) bt
Thread 2 received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1]
_outb (addr=<optimized out>, value=<optimized out>) at ./include/asm-generic/io.h:584
584 __raw_writeb(value, PCI_IOBASE + addr);
(gdb) bt
0 _outb (addr=<optimized out>, value=<optimized out>) at ./include/asm-generic/io.h:584
1 logic_outb (value=0 '\000', addr=18446739675637874689) at lib/logic_pio.c:299
2 0xffff80008082dfcc in io_serial_out (p=0x0, offset=16760830, value=0) at drivers/tty/serial/8250/8250_port.c:416
3 0xffff80008082fe34 in serial_port_out (value=<optimized out>, offset=<optimized out>, up=<optimized out>)
at ./include/linux/serial_core.h:677
4 serial8250_do_set_termios (port=0xffff8000828ee940 <serial8250_ports+1568>, termios=0xffff80008292b93c, old=0x0)
at drivers/tty/serial/8250/8250_port.c:2860
5 0xffff800080830064 in serial8250_set_termios (port=0xfffffbfffe800000, termios=0xffbffe, old=0x0)
at drivers/tty/serial/8250/8250_port.c:2912
6 0xffff80008082571c in uart_set_options (port=0xffff8000828ee940 <serial8250_ports+1568>, co=0x0, baud=115200, parity=110, bits=8, flow=110)
at drivers/tty/serial/serial_core.c:2285
7 0xffff800080828434 in uart_poll_init (driver=0xfffffbfffe800000, line=16760830, options=0xffff8000828f7506 <config+6> "115200n8")
at drivers/tty/serial/serial_core.c:2656
8 0xffff800080801690 in tty_find_polling_driver (name=0xffff8000828f7500 <config> "ttyS2,115200n8", line=0xffff80008292ba90)
at drivers/tty/tty_io.c:410
9 0xffff80008086c0b0 in configure_kgdboc () at drivers/tty/serial/kgdboc.c:194
10 0xffff80008086c1ec in kgdboc_probe (pdev=0xfffffbfffe800000) at drivers/tty/serial/kgdboc.c:249
11 0xffff8000808b399c in platform_probe (_dev=0xffff000000ebb810) at drivers/base/platform.c:1404
12 0xffff8000808b0b44 in call_driver_probe (drv=<optimized out>, dev=<optimized out>) at drivers/base/dd.c:579
13 really_probe (dev=0xffff000000ebb810, drv=0xffff80008277f138 <kgdboc_platform_driver+48>) at drivers/base/dd.c:658
14 0xffff8000808b0d2c in __driver_probe_device (drv=0xffff80008277f138 <kgdboc_platform_driver+48>, dev=0xffff000000ebb810)
at drivers/base/dd.c:800
15 0xffff8000808b0eb8 in driver_probe_device (drv=0xfffffbfffe800000, dev=0xffff000000ebb810) at drivers/base/dd.c:830
16 0xffff8000808b0ff4 in __device_attach_driver (drv=0xffff80008277f138 <kgdboc_platform_driver+48>, _data=0xffff80008292bc48)
at drivers/base/dd.c:958
17 0xffff8000808ae970 in bus_for_each_drv (bus=0xfffffbfffe800000, start=0x0, data=0xffff80008292bc48,
fn=0xffff8000808b0f3c <__device_attach_driver>) at drivers/base/bus.c:457
18 0xffff8000808b1408 in __device_attach (dev=0xffff000000ebb810, allow_async=true) at drivers/base/dd.c:1030
19 0xffff8000808b16d8 in device_initial_probe (dev=0xfffffbfffe800000) at drivers/base/dd.c:1079
20 0xffff8000808af9f4 in bus_probe_device (dev=0xffff000000ebb810) at drivers/base/bus.c:532
21 0xffff8000808ac77c in device_add (dev=0xfffffbfffe800000) at drivers/base/core.c:3625
22 0xffff8000808b3428 in platform_device_add (pdev=0xffff000000ebb800) at drivers/base/platform.c:716
23 0xffff800081b5dc0c in init_kgdboc () at drivers/tty/serial/kgdboc.c:292
24 0xffff800080014db0 in do_one_initcall (fn=0xffff800081b5dba4 <init_kgdboc>) at init/main.c:1236
25 0xffff800081b0114c in do_initcall_level (command_line=<optimized out>, level=<optimized out>) at init/main.c:1298
26 do_initcalls () at init/main.c:1314
27 do_basic_setup () at init/main.c:1333
28 kernel_init_freeable () at init/main.c:1551
29 0xffff8000810271ec in kernel_init (unused=0xfffffbfffe800000) at init/main.c:1441
30 0xffff800080015e80 in ret_from_fork () at arch/arm64/kernel/entry.S:857
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Link: https://lore.kernel.org/r/20231224131200.266224-1-michael@amarulasolutions.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add "SER_RS485_MODE_RS422" flag to struct serial_rs485, so that serial
port can switch interface into RS422 if supported by using ioctl command
"TIOCSRS485".
By treating RS422 as a mode of RS485, which means while enabling RS422
there are two flags need to be set (SER_RS485_ENABLED and
SER_RS485_MODE_RS422), it would make things much easier. For example
some places that checks for "SER_RS485_ENABLED" won't need to be rewritten.
Signed-off-by: Crescent CY Hsieh <crescentcy.hsieh@moxa.com>
Link: https://lore.kernel.org/r/20231201071554.258607-3-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rename the variable size to temp and change its data type from
unsigned int to u64 to avoid type casting in multiplication. Remove the
intermediate variable frame_time and use temp instead to accommodate
the nanoseconds(ns). port->frame_time is an unsigned int, therefore an
explicit cast is used to improve readability. Having said this unsigned
int is sufficinet to hold frame time duration in nanoseconds for all
the standard baudrates.
Consider 9600 baud, it takes 1/9600 seconds for one bit, for a total of
10 bits (start, 8-bit data, stop) 10/9600=1.04 ms for 1 byte transfer,
frame_time here is 1041667ns. As baudrate increases frame_time
decreases, say for 115200 baud it is 86806ns.
To avoid costly 64-bit arithmetic we do not upconvert the type for
variable frame_time as overflow happens for extremely low baudrates
which are impractical and are not used in real-world applications.
Signed-off-by: Vamshi Gajjela <vamshigajjela@google.com>
Link: https://lore.kernel.org/r/20231109063417.3971005-3-vamshigajjela@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_operations::send_xchar is one of the last users of 'char' type for
characters in the tty layer. Convert it to u8 now.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Cc: netdev@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
Cc: linux-bluetooth@vger.kernel.org
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20231206073712.17776-5-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
