[ Upstream commit e60955dbec ]
Sparse is not happy about misuse of bitwise types:
.../max3100.c:194:13: warning: incorrect type in assignment (different base types)
.../max3100.c:194:13: expected unsigned short [addressable] [usertype] etx
.../max3100.c:194:13: got restricted __be16 [usertype]
.../max3100.c:202:15: warning: cast to restricted __be16
Fix this by choosing proper types for the respective variables.
Fixes: 7831d56b0a ("tty: MAX3100")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240402195306.269276-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 712a1fcb38 ]
The removal of the last MAX3100 device triggers the removal of
the driver. However, code doesn't update the respective global
variable and after insmod — rmmod — insmod cycle the kernel
oopses:
max3100 spi-PRP0001:01: max3100_probe: adding port 0
BUG: kernel NULL pointer dereference, address: 0000000000000408
...
RIP: 0010:serial_core_register_port+0xa0/0x840
...
max3100_probe+0x1b6/0x280 [max3100]
spi_probe+0x8d/0xb0
Update the actual state so next time UART driver will be registered
again.
Hugo also noticed, that the error path in the probe also affected
by having the variable set, and not cleared. Instead of clearing it
move the assignment after the successfull uart_register_driver() call.
Fixes: 7831d56b0a ("tty: MAX3100")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20240402195306.269276-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 77ab53371a ]
uart_handle_cts_change() has to be called with port lock taken,
Since we run it in a separate work, the lock may not be taken at
the time of running. Make sure that it's taken by explicitly doing
that. Without it we got a splat:
WARNING: CPU: 0 PID: 10 at drivers/tty/serial/serial_core.c:3491 uart_handle_cts_change+0xa6/0xb0
...
Workqueue: max3100-0 max3100_work [max3100]
RIP: 0010:uart_handle_cts_change+0xa6/0xb0
...
max3100_handlerx+0xc5/0x110 [max3100]
max3100_work+0x12a/0x340 [max3100]
Fixes: 7831d56b0a ("tty: MAX3100")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240402195306.269276-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 614a19b89c upstream.
There is a scenario when resuming from some power saving states
with no_console_suspend where console output can be generated
before the 8250_bcm7271 driver gets the opportunity to restore
the baud_mux_clk frequency. Since the baud_mux_clk is at its
default frequency at this time the output can be garbled until
the driver gets the opportunity to resume.
Since this is only an issue with console use of the serial port
during that window and the console isn't likely to use baud
rates that require alternate baud_mux_clk frequencies, allow the
driver to select the default_mux_rate if it is accurate enough.
Fixes: 41a469482d ("serial: 8250: Add new 8250-core based Broadcom STB driver")
Cc: stable@vger.kernel.org
Signed-off-by: Doug Berger <opendmb@gmail.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20240424222559.1844045-1-opendmb@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 70d7f1427a upstream.
The current implementation uses either gsm0_receive() or gsm1_receive()
depending on whether the user configured the mux in basic or advanced
option mode. Both functions share some state values over the same logical
elements of the frame. However, both frame types differ in their nature.
gsm0_receive() uses non-transparency framing, whereas gsm1_receive() uses
transparency mechanism. Switching between both modes leaves the receive
function in an undefined state when done during frame reception.
Fix this by splitting both states. Add gsm0_receive_state_check_and_fix()
and gsm1_receive_state_check_and_fix() to ensure that gsm->state is reset
after a change of gsm->receive.
Note that gsm->state is only accessed in:
- gsm0_receive()
- gsm1_receive()
- gsm_error()
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/20240424054842.7741-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 47388e807f upstream.
Assuming the following:
- side A configures the n_gsm in basic option mode
- side B sends the header of a basic option mode frame with data length 1
- side A switches to advanced option mode
- side B sends 2 data bytes which exceeds gsm->len
Reason: gsm->len is not used in advanced option mode.
- side A switches to basic option mode
- side B keeps sending until gsm0_receive() writes past gsm->buf
Reason: Neither gsm->state nor gsm->len have been reset after
reconfiguration.
Fix this by changing gsm->count to gsm->len comparison from equal to less
than. Also add upper limit checks against the constant MAX_MRU in
gsm0_receive() and gsm1_receive() to harden against memory corruption of
gsm->len and gsm->mru.
All other checks remain as we still need to limit the data according to the
user configuration and actual payload size.
Reported-by: j51569436@gmail.com
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218708
Tested-by: j51569436@gmail.com
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/20240424054842.7741-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 54c4ec5f8c upstream.
The uart_handle_cts_change() function in serial_core expects the caller
to hold uport->lock. For example, I have seen the below kernel splat,
when the Bluetooth driver is loaded on an i.MX28 board.
[ 85.119255] ------------[ cut here ]------------
[ 85.124413] WARNING: CPU: 0 PID: 27 at /drivers/tty/serial/serial_core.c:3453 uart_handle_cts_change+0xb4/0xec
[ 85.134694] Modules linked in: hci_uart bluetooth ecdh_generic ecc wlcore_sdio configfs
[ 85.143314] CPU: 0 PID: 27 Comm: kworker/u3:0 Not tainted 6.6.3-00021-gd62a2f068f92 #1
[ 85.151396] Hardware name: Freescale MXS (Device Tree)
[ 85.156679] Workqueue: hci0 hci_power_on [bluetooth]
(...)
[ 85.191765] uart_handle_cts_change from mxs_auart_irq_handle+0x380/0x3f4
[ 85.198787] mxs_auart_irq_handle from __handle_irq_event_percpu+0x88/0x210
(...)
Cc: stable@vger.kernel.org
Fixes: 4d90bb147e ("serial: core: Document and assert lock requirements for irq helpers")
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Emil Kronborg <emil.kronborg@protonmail.com>
Link: https://lore.kernel.org/r/20240320121530.11348-1-emil.kronborg@protonmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 672448ccf9 upstream.
When about to transmit the function imx_uart_start_tx is called and in
some RS485 configurations this function will call imx_uart_stop_rx. The
problem is that imx_uart_stop_rx will enable loopback in order to
release the RS485 bus, but when loopback is enabled transmitted data
will just be looped to RX.
This patch fixes the above problem by not enabling loopback when about
to transmit.
This driver now works well when used for RS485 half duplex master
configurations.
Fixes: 79d0224f6b ("tty: serial: imx: Handle RS485 DE signal active high")
Cc: stable <stable@kernel.org>
Signed-off-by: Rickard x Andersson <rickaran@axis.com>
Tested-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>
Link: https://lore.kernel.org/r/20240221115304.509811-1-rickaran@axis.com
Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 74cb7e0355 upstream.
If the remote uart device is not connected or not enabled after booting
up, the CTS line is high by default. At this time, if we enable the flow
control when opening the device(for example, using “stty -F /dev/ttyLP4
crtscts” command), there will be a pending idle preamble(first writing 0
and then writing 1 to UARTCTRL_TE will queue an idle preamble) that
cannot be sent out, resulting in the uart port fail to close(waiting for
TX empty), so the user space stty will have to wait for a long time or
forever.
This is an LPUART IP bug(idle preamble has higher priority than CTS),
here add a workaround patch to enable TX CTS after enabling UARTCTRL_TE,
so that the idle preamble does not get stuck due to CTS is deasserted.
Fixes: 380c966c09 ("tty: serial: fsl_lpuart: add 32-bit register interface support")
Cc: stable <stable@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Link: https://lore.kernel.org/r/20240305015706.1050769-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 801410b26a ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0d27056c24 ]
When trying to instantiate a max14830 device from userspace:
echo max14830 0x60 > /sys/bus/i2c/devices/i2c-2/new_device
we get the following error:
Unable to handle kernel NULL pointer dereference at virtual address...
...
Call trace:
max310x_i2c_probe+0x48/0x170 [max310x]
i2c_device_probe+0x150/0x2a0
...
Add check for validity of devtype to prevent the error, and abort probe
with a meaningful error message.
Fixes: 2e1f2d9a9b ("serial: max310x: implement I2C support")
Cc: stable@vger.kernel.org
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20240118152213.2644269-2-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e0f25b8992 ]
The capability CAP_CHECKPOINT_RESTORE was introduced to allow non-root
users to checkpoint and restore processes as non-root with CRIU.
This change extends CAP_CHECKPOINT_RESTORE to enable the CRIU option
'--shell-job' as non-root. CRIU's man-page describes the '--shell-job'
option like this:
Allow one to dump shell jobs. This implies the restored task will
inherit session and process group ID from the criu itself. This option
also allows to migrate a single external tty connection, to migrate
applications like top.
TIOCSLCKTRMIOS can only be done if the process has CAP_SYS_ADMIN and
this change extends it to CAP_SYS_ADMIN or CAP_CHECKPOINT_RESTORE.
With this change it is possible to checkpoint and restore processes
which have a tty connection as non-root if CAP_CHECKPOINT_RESTORE is
set.
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Adrian Reber <areber@redhat.com>
Acked-by: Andrei Vagin <avagin@gmail.com>
Link: https://lore.kernel.org/r/20231208143656.1019-1-areber@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9915753037 ]
Commit cc4c1d05eb ("sc16is7xx: Properly resume TX after stop") changed
behavior to unconditionnaly set the THRI interrupt in sc16is7xx_tx_proc().
For example when sending a 65 bytes message, and assuming the Tx FIFO is
initially empty, sc16is7xx_handle_tx() will write the first 64 bytes of the
message to the FIFO and sc16is7xx_tx_proc() will then activate THRI. When
the THRI IRQ is fired, the driver will write the remaining byte of the
message to the FIFO, and disable THRI by calling sc16is7xx_stop_tx().
When sending a 2 bytes message, sc16is7xx_handle_tx() will write the 2
bytes of the message to the FIFO and call sc16is7xx_stop_tx(), disabling
THRI. After sc16is7xx_handle_tx() exits, control returns to
sc16is7xx_tx_proc() which will unconditionally set THRI. When the THRI IRQ
is fired, the driver simply acknowledges the interrupt and does nothing
more, since all the data has already been written to the FIFO. This results
in 2 register writes and 4 register reads all for nothing and taking
precious cycles from the I2C/SPI bus.
Fix this by enabling the THRI interrupt only when we fill the Tx FIFO to
its maximum capacity and there are remaining bytes to send in the message.
Fixes: cc4c1d05eb ("sc16is7xx: Properly resume TX after stop")
Cc: <stable@vger.kernel.org>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20231211171353.2901416-7-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b465848be8 ]
When a serial port is used for kernel console output, then all
modifications to the UART registers which are done from other contexts,
e.g. getty, termios, are interference points for the kernel console.
So far this has been ignored and the printk output is based on the
principle of hope. The rework of the console infrastructure which aims to
support threaded and atomic consoles, requires to mark sections which
modify the UART registers as unsafe. This allows the atomic write function
to make informed decisions and eventually to restore operational state. It
also allows to prevent the regular UART code from modifying UART registers
while printk output is in progress.
All modifications of UART registers are guarded by the UART port lock,
which provides an obvious synchronization point with the console
infrastructure.
To avoid adding this functionality to all UART drivers, wrap the
spin_[un]lock*() invocations for uart_port::lock into helper functions
which just contain the spin_[un]lock*() invocations for now. In a
subsequent step these helpers will gain the console synchronization
mechanisms.
Converted with coccinelle. No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20230914183831.587273-56-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 9915753037 ("serial: sc16is7xx: fix unconditional activation of THRI interrupt")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 8a1060ce97 upstream.
If an error occurs during probing, the sc16is7xx_lines bitfield may be left
in a state that doesn't represent the correct state of lines allocation.
For example, in a system with two SC16 devices, if an error occurs only
during probing of channel (port) B of the second device, sc16is7xx_lines
final state will be 00001011b instead of the expected 00000011b.
This is caused in part because of the "i--" in the for/loop located in
the out_ports: error path.
Fix this by checking the return value of uart_add_one_port() and set line
allocation bit only if this was successful. This allows the refactor of
the obfuscated for(i--...) loop in the error path, and properly call
uart_remove_one_port() only when needed, and properly unset line allocation
bits.
Also use same mechanism in remove() when calling uart_remove_one_port().
Fixes: c64349722d ("sc16is7xx: support multiple devices")
Cc: <stable@vger.kernel.org>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20231221231823.2327894-2-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dbf4ab8218 upstream.
The SC16IS7XX IC supports a burst mode to access the FIFOs where the
initial register address is sent ($00), followed by all the FIFO data
without having to resend the register address each time. In this mode, the
IC doesn't increment the register address for each R/W byte.
The regmap_raw_read() and regmap_raw_write() are functions which can
perform IO over multiple registers. They are currently used to read/write
from/to the FIFO, and although they operate correctly in this burst mode on
the SPI bus, they would corrupt the regmap cache if it was not disabled
manually. The reason is that when the R/W size is more than 1 byte, these
functions assume that the register address is incremented and handle the
cache accordingly.
Convert FIFO R/W functions to use the regmap _noinc_ versions in order to
remove the manual cache control which was a workaround when using the
_raw_ versions. FIFO registers are properly declared as volatile so
cache will not be used/updated for FIFO accesses.
Fixes: dfeae619d7 ("serial: sc16is7xx")
Cc: <stable@vger.kernel.org>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20231211171353.2901416-6-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6bcab3c8ac upstream.
Using a static buffer inside sc16is7xx_regmap_name() was a convenient and
simple way to set the regmap name without having to allocate and free a
buffer each time it is called. The drawback is that the static buffer
wastes memory for nothing once regmap is fully initialized.
Remove static buffer and use constant strings instead.
This also avoids a truncation warning when using "%d" or "%u" in snprintf
which was flagged by kernel test robot.
Fixes: 3837a03795 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port")
Cc: <stable@vger.kernel.org> # 6.1.x: 3837a03 serial: sc16is7xx: improve regmap debugfs by using one regmap per port
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20231211171353.2901416-2-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3837a03795 upstream.
With this current driver regmap implementation, it is hard to make sense
of the register addresses displayed using the regmap debugfs interface,
because they do not correspond to the actual register addresses documented
in the datasheet. For example, register 1 is displayed as registers 04 thru
07:
$ cat /sys/kernel/debug/regmap/spi0.0/registers
04: 10 -> Port 0, register offset 1
05: 10 -> Port 1, register offset 1
06: 00 -> Port 2, register offset 1 -> invalid
07: 00 -> port 3, register offset 1 -> invalid
...
The reason is that bits 0 and 1 of the register address correspond to the
channel (port) bits, so the register address itself starts at bit 2, and we
must 'mentally' shift each register address by 2 bits to get its real
address/offset.
Also, only channels 0 and 1 are supported by the chip, so channel mask
combinations of 10b and 11b are invalid, and the display of these
registers is useless.
This patch adds a separate regmap configuration for each port, similar to
what is done in the max310x driver, so that register addresses displayed
match the register addresses in the chip datasheet. Also, each port now has
its own debugfs entry.
Example with new regmap implementation:
$ cat /sys/kernel/debug/regmap/spi0.0-port0/registers
1: 10
2: 01
3: 00
...
$ cat /sys/kernel/debug/regmap/spi0.0-port1/registers
1: 10
2: 01
3: 00
As an added bonus, this also simplifies some operations (read/write/modify)
because it is no longer necessary to manually shift register addresses.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20231030211447.974779-1-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 66aad7d8d3 ]
In ACM support for sending breaks to devices is optional.
If a device says that it doenot support sending breaks,
the host must respect that.
Given the number of optional features providing tty operations
for each combination is not practical and errors need to be
returned dynamically if unsupported features are requested.
In case a device does not support break, we want the tty layer
to treat that like it treats drivers that statically cannot
support sending a break. It ignores the inability and does nothing.
This patch uses EOPNOTSUPP to indicate that.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Fixes: 9e98966c7b ("tty: rework break handling")
Link: https://lore.kernel.org/r/20231207132639.18250-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 66619686d1 ]
If the driver sets TTY_DRIVER_HARDWARE_BREAK, we leave ops->break_ctl()
to the driver and return from send_break(). But we do it using a local
variable and keep the code flowing through the end of the function.
Instead, do 'return' immediately with the ops->break_ctl()'s return
value.
This way, we don't have to stuff the 'else' branch of the 'if' with the
software break handling. And we can re-indent the function too.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230919085156.1578-14-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 66aad7d8d3 ("usb: cdc-acm: return correct error code on unsupported break")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 78d60dae9a ]
When using the serial port as RS485 port, the tx statemachine is used to
control the RTS pin to drive the RS485 transceiver TX_EN pin. When the
TTY port is closed in the middle of a transmission (for instance during
userland application crash), imx_uart_shutdown disables the interface
and disables the Transmission Complete interrupt. afer that,
imx_uart_stop_tx bails on an incomplete transmission, to be retriggered
by the TC interrupt. This interrupt is disabled and therefore the tx
statemachine never transitions out of SEND. The statemachine is in
deadlock now, and the TX_EN remains low, making the interface useless.
imx_uart_stop_tx now checks for incomplete transmission AND whether TC
interrupts are enabled before bailing to be retriggered. This makes sure
the state machine handling is reached, and is properly set to
WAIT_AFTER_SEND.
Fixes: cb1a609236 ("serial: imx: implement rts delaying for rs485")
Signed-off-by: Paul Geurts <paul_geurts@live.nl>
Tested-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Tested-by: Eberhard Stoll <eberhard.stoll@gmx.de>
Link: https://lore.kernel.org/r/AM0PR09MB26758F651BC1B742EB45775995B8A@AM0PR09MB2675.eurprd09.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ad90d0358b ]
Returning an error code from .remove() makes the driver core emit the
little helpful error message:
remove callback returned a non-zero value. This will be ignored.
and then remove the device anyhow. So all resources that were not freed
are leaked in this case. Skipping serial8250_unregister_port() has the
potential to keep enough of the UART around to trigger a use-after-free.
So replace the error return (and with it the little helpful error
message) by a more useful error message and continue to cleanup.
Fixes: e3f0c638f4 ("serial: 8250: omap: Fix unpaired pm_runtime_put_sync() in omap8250_remove()")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20231110152927.70601-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Wolfram Sang
Hugo Villeneuve
Andy Shevchenko
Pin-yen Lin
Doug Berger
Daniel Starke
Daniel Thompson
Uwe Kleine-König
Finn Thain
Emil Kronborg
Thadeu Lima de Souza Cascardo
Rickard x Andersson
Nicolas Pitre
Sherry Sun
Peter Collingbourne
Tudor Ambarus
Jiri Slaby (SUSE)
Lino Sanfilippo
Adrian Reber
Thomas Gleixner
Christoph Niedermaier
Oliver Neukum
Paul Geurts