Commit ffd381445e ("serial: 8250: dw: Move the USR register to pdata")
caused NULL-pointer dereference when booting with ACPI by unconditional
usage of the recently added pdata.
In order to fix that and prevent similar issues in future, hook the
default version of this structure in dw8250_acpi_match table.
While at it, sort all entries alphabetically.
Fixes: ffd381445e ("serial: 8250: dw: Move the USR register to pdata")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Marcin Wojtas <mw@semihalf.com>
Link: https://lore.kernel.org/r/20220620121046.1307412-1-mw@semihalf.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add 9th bit multipoint addressing mode for DW UART. 9th bit addressing
can be used only when HW RS485 is available.
Updating RAR (receive address register) is bit tricky because busy
indication is not be available when DW UART is strictly 16550
compatible, which is the case with the hardware I was testing with. RAR
should not be updated while receive is in progress which is now
achieved by deasserting RE and waiting for one frame (in case rx would
be in progress, the driver seems to have no way of knowing it w/o busy
indication). Because of this complexity, it's better to avoid doing it
unless really needed.
Co-developed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Co-developed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Co-developed-by: Raymond Tan <raymond.tan@intel.com>
Co-developed-by: Lakshmi Sowjanya <lakshmi.sowjanya.d@intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Raymond Tan <raymond.tan@intel.com>
Signed-off-by: Lakshmi Sowjanya <lakshmi.sowjanya.d@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220624204210.11112-7-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for RS-485 multipoint addressing using 9th bit [*]. The
addressing mode is configured through ->rs485_config().
ADDRB in termios indicates 9th bit addressing mode is enabled. In this
mode, 9th bit is used to indicate an address (byte) within the
communication line. ADDRB can only be enabled/disabled through
->rs485_config() that is also responsible for setting the destination and
receiver (filter) addresses.
Add traps to detect unwanted changes to struct serial_rs485 layout using
static_assert().
[*] Technically, RS485 is just an electronic spec and does not itself
specify the 9th bit addressing mode but 9th bit seems at least
"semi-standard" way to do addressing with RS485.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220624204210.11112-6-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To be able to alter ADDRB within ->rs485_config(), take termios_rwsem
before calling ->rs485_config() and pass termios.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220624204210.11112-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use 32-bit reads in order to not lose higher bits of DW UART regs. This
change does not fix any known issue as the high bits are not used for
anything related to 8250 driver (dw8250_readl_ext and dw8250_writel_ext
used within the dwlib are already doing
readl/writel/ioread32be/iowrite32be anyway).
This change is necessary to enables 9th bit address mode. DW UART
reports address frames with BIT(8) of LSR.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220624204210.11112-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
DW flags address received as BIT(8) in LSR. In order to not lose that
on read, enlarge lsr_saved_flags to u16.
Adjust lsr/status variables and related call chains to use u16.
Technically, some of these type conversion would not be needed but it
doesn't hurt to be consistent.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220624204210.11112-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Per file BOTH_EMPTY defines are littering our source code here and
there. Define once in serial.h and create helper for the check
too.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220624205424.12686-7-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Both UART_XMIT_SIZE and SERIAL_XMIT_SIZE are defined. Make them all
UART_XMIT_SIZE.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220624205424.12686-6-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use C99 array initializer insteads of comments and make unmapped checks
more obvious.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220624205424.12686-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Using UART_* to name defines is a bit problematic. When trying to do
unrelated cleanup which also involved tweaking header inclusion logic,
caused UART_CSR from serial_reg.h to leak into msm's namespace which is
also among msm defines. Thus, rename all UART_* ones to MSM_UART_* to
eliminate possibility of collisions.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220624205424.12686-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Create static inline instead of define as it provides type safety and
is safer wrt. macros expansion.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220624205424.12686-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need for clk_prepare_enable() at the beginning of
atmel_console_setup() and clk_disable_unprepare() at the end of
atmel_console_setup() as the clock is already enabled when calling
atmel_console_setup() and its disablement is done at the end
of probe.
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220616140024.2081238-4-claudiu.beznea@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use devm_clk_get() for serial clock instead of clk_get()/clk_put().
With this move the clk_get in driver's probe function.
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220616140024.2081238-3-claudiu.beznea@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stop using legacy PM ops and switch using dev_pm_ops. Along with
it #ifdef CONFIG_PM are removed and __maybe_unused and pm_ptr() used
instead. Coding style recommends (at chapter Conditional Compilation)
to avoid using preprocessor conditional and use __maybe_unused
instead.
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220616140024.2081238-2-claudiu.beznea@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In soc_info(), of_find_node_by_type() will return a node pointer
with refcount incremented. We should use of_node_put() when it is
not used anymore.
Acked-by: Timur Tabi <timur@kernel.org>
Signed-off-by: Liang He <windhl@126.com>
Link: https://lore.kernel.org/r/20220618060850.4058525-1-windhl@126.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In tegra_uart_init(), of_find_matching_node() will return a node
pointer with refcount incremented. We should use of_node_put()
when it is not used anymore.
Signed-off-by: Liang He <windhl@126.com>
Link: https://lore.kernel.org/r/20220615111747.3963930-1-windhl@126.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 31f6bd7fad ("serial: Store character timing information
to uart_port"), per frame timing information is available on uart_port.
Uart port's timeout can be derived from frame_time by multiplying with
fifosize.
Most callers of uart_poll_timeout are not made under port's lock. To be
on the safe side, make sure frame_time is only accessed once. As
fifo_size is effectively a constant, it shouldn't cause any issues.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220613113905.22962-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Switch mpc5xxx_get_bus_frequency() to use fwnode in order to help
cleaning up other parts of the kernel from OF specific code.
No functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Chris Packham <chris.packham@alliedtelesis.co.nz> # for i2c-mpc
Acked-by: Wolfram Sang <wsa@kernel.org> # for the I2C part
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for mscan/mpc5xxx_can
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220507100147.5802-2-andriy.shevchenko@linux.intel.com
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Merge tag 'v5.19-rc3' into tty-next
We need the tty/serial fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Disable MMIO tracing for geni serial driver to prevent excessive
logging. Any access over serial console would involve a lot of
TX and RX register accesses (and few others), so these MMIO
read/write trace events in these drivers cause a lot of unwanted
noise because of the high frequency of such operations and it is
not very useful tracing these events for such drivers.
Given we want to enable these trace events on development devices
(maybe not production devices) where performance also really matters
so that we don't regress other components by wasting CPU cycles and
memory collecting these traces, it makes more sense to disable these
traces from such drivers.
Also another reason to disable these traces would be to prevent
recursive tracing when we display the trace buffer containing
these MMIO trace events since writing onto serial console would
further record MMIO traces.
Signed-off-by: Sai Prakash Ranjan <quic_saipraka@quicinc.com>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Not all LSR register flags are preserved across reads. Therefore, LSR
readers must store the non-preserved bits into lsr_save_flags.
This fix was initially mixed into feature commit f6f586102a ("serial:
8250: Handle UART without interrupt on TEMT using em485"). However,
that feature change had a flaw and it was reverted to make room for
simpler approach providing the same feature. The embedded fix got
reverted with the feature change.
Re-add the lsr_save_flags fix and properly mark it's a fix.
Link: https://lore.kernel.org/all/1d6c31d-d194-9e6a-ddf9-5f29af829f3@linux.intel.com/T/#m1737eef986bd20cf19593e344cebd7b0244945fc
Fixes: e490c9144c ("tty: Add software emulated RS485 support for 8250")
Cc: stable <stable@kernel.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@penugtronix.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/f4d774be-1437-a550-8334-19d8722ab98c@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Serial core handles serial_rs485 sanitization.
When em485 init fails, there are two possible paths of entry:
1) uart_rs485_config (init path) that fully clears port->rs485 on
error.
2) ioctl path with a pre-existing, valid port->rs485 unto which the
kernel falls back on error and port->rs485 should therefore be
kept untouched. The temporary rs485 struct is not returned to
userspace in case of error so its flag don't matter.
...Thus SER_RS485_ENABLED clearing on error can/should be dropped.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-37-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Serial core handles serial_rs485 assignment. It is safe to remove this
assignment because sc16is7xx_reg_proc() takes port.lock at start (and
sc16is7xx_reconf_rs485() would too).
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-36-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver provides different rs485_supported for the case where RTS is
not available making it unnecessary to handle it in
imx_uart_rs485_config.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-32-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Serial core handles serial_rs485 sanitization. Remove custom
sanitization from lpuart_config_rs485.
This change loses dev_err when SER_RS485_RX_DURING_TX is set due to
incorrect configuration. Other drivers do not do similar prinout for
full-duplex case and it should be done in serial core if it is
desirable to notify on this condition. Personally, I doesn't see it
important because the kernel gracefully downgrades to half-duplex.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-31-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Serial core handles serial_rs485 sanitization and rs485 struct
assignment. As serial_rs485 is already clear for the non-RS485 case by
serial core, there no need to clear flags in the driver.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-26-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In order to be add new flags more cleanly and safely, return -EINVAL
from TIOCSRS485 ioctl for the flags bits which are not among the
current legacy ones.
This might cause a regression for userspace as those non-flag bits do
not currently trigger -EINVAL. However, it would only occur if the
userspace is sending garbage bits so perhaps we'll get away with this
change.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-25-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When SER_RS485_ENABLED is not set, having any other flag/field set in
serial_rs485 struct does not have an effect different from not having
them set. Thus, make the serial_rs485 struct also match the behavior
for all flags, not just SER_RS485_ENABLED.
Some drivers do similar clearing of rs485 struct in their
rs485_config() already, but not all. This change makes the behavior
consistent across drivers.
Don't try to validate rs485 struct further when no RS485 is requested,
this silences some bogus warnings.
This change has (minor) userspace visible impact.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-24-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sanitize serial_rs485 struct before calling into rs485_setup. The
drivers provide supported_rs485 to help sanitization of the fields.
If neither of SER_RS485_RTS_ON_SEND or SER_RS485_RTS_AFTER_SEND
supported, don't pretend they can be set to sane settings but clear
them both instead. If only one of them is supported it may look
tempting to use the one driver supports to set the other, however, the
userspace does not have that information readily available so it
wouldn't be helpful.
While adjusting the documentation, remove also the claim that
TIOCGRS485 would call driver specific code. In reality, it does nothing
else than copies the stored serial_rs485 structure from uart_port to
userspace.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-23-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add information on supported serial_rs485 features.
This driver does not support delay_rts_after_send but the pre-existing
behavior is to return -EINVAL if delay_rts_after_send is non-zero. In
contrast, other drivers that do not support delay_rts_after_send either
zero delay_rts_after_send or do not care (leave the inaccurate value).
As changing this would cause userspace visible impact, the change is
not attempted here. But perhaps it should be still tried (maybe nobody
finds that kind of API oddity significant)?
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-21-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add information on supported serial_rs485 features.
In the case where RTS is lacking, RS485 cannot be enabled so provide
zero rs485_supported for that case. Perhaps it would make sense to not
provide rs485_config() at all in that case but such a change would have
userspace visible impact/change in behavior so this patch does not
attempt it.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-17-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
