serial: xilinx_uartps: Switch to use hrtimer_setup()

hrtimer_setup() takes the callback function pointer as argument and
initializes the timer completely.

Replace hrtimer_init() and the open coded

serial: xilinx_uartps: Switch to use hrtimer_setup()

hrtimer_setup() takes the callback function pointer as argument and
initializes the timer completely.

Replace hrtimer_init() and the open coded initialization of
hrtimer::function with the new setup mechanism.

Patch was created by using Coccinelle.

Acked-by: Zack Rusin <[email protected]>
Signed-off-by: Nam Cao <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Link: https://lore.kernel.org/r/4a028a23126b3350a5e243dcb49e1ef1b2a4b740.1738746904.git.namcao@linutronix.de
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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serial: xilinx_uartps: Use helper function hrtimer_update_function()

The field 'function' of struct hrtimer should not be changed directly, as
the write is lockless and a concurrent timer expiry mig

serial: xilinx_uartps: Use helper function hrtimer_update_function()

The field 'function' of struct hrtimer should not be changed directly, as
the write is lockless and a concurrent timer expiry might end up using the
wrong function pointer.

Switch to use hrtimer_update_function() which also performs runtime checks
that it is safe to modify the callback.

Signed-off-by: Nam Cao <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Link: https://lore.kernel.org/r/af7823518fb060c6c97105a2513cfc61adbdf38f.1738746927.git.namcao@linutronix.de
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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serial: xilinx_uartps: Use helper function hrtimer_update_function()

The field 'function' of struct hrtimer should not be changed directly, as
the write is lockless and a concurrent timer expiry mig

serial: xilinx_uartps: Use helper function hrtimer_update_function()

The field 'function' of struct hrtimer should not be changed directly, as
the write is lockless and a concurrent timer expiry might end up using the
wrong function pointer.

Switch to use hrtimer_update_function() which also performs runtime checks
that it is safe to modify the callback.

Signed-off-by: Nam Cao <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/all/af7823518fb060c6c97105a2513cfc61adbdf38f.1738746927.git.namcao@linutronix.de

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serial: xilinx_uartps: Switch to use hrtimer_setup()

hrtimer_setup() takes the callback function pointer as argument and
initializes the timer completely.

Replace hrtimer_init() and the open coded

serial: xilinx_uartps: Switch to use hrtimer_setup()

hrtimer_setup() takes the callback function pointer as argument and
initializes the timer completely.

Replace hrtimer_init() and the open coded initialization of
hrtimer::function with the new setup mechanism.

Patch was created by using Coccinelle.

Signed-off-by: Nam Cao <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Zack Rusin <[email protected]>
Link: https://lore.kernel.org/all/4a028a23126b3350a5e243dcb49e1ef1b2a4b740.1738746904.git.namcao@linutronix.de

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tty: xilinx_uartps: split sysrq handling

lockdep detects the following circular locking dependency:

CPU 0 CPU 1
========================== ============================
cdns_uar

tty: xilinx_uartps: split sysrq handling

lockdep detects the following circular locking dependency:

CPU 0 CPU 1
========================== ============================
cdns_uart_isr() printk()
uart_port_lock(port) console_lock()
cdns_uart_console_write()
if (!port->sysrq)
uart_port_lock(port)
uart_handle_break()
port->sysrq = ...
uart_handle_sysrq_char()
printk()
console_lock()

The fixed commit attempts to avoid this situation by only taking the
port lock in cdns_uart_console_write if port->sysrq unset. However, if
(as shown above) cdns_uart_console_write runs before port->sysrq is set,
then it will try to take the port lock anyway. This may result in a
deadlock.

Fix this by splitting sysrq handling into two parts. We use the prepare
helper under the port lock and defer handling until we release the lock.

Fixes: 74ea66d4ca06 ("tty: xuartps: Improve sysrq handling")
Signed-off-by: Sean Anderson <[email protected]>
Cc: [email protected] # c980248179d: serial: xilinx_uartps: Use port lock wrappers
Acked-by: John Ogness <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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serial: Switch back to struct platform_driver::remove()

After commit 0edb555a65d1 ("platform: Make platform_driver::remove()
return void") .remove() is (again) the right callback to implement for
pl

serial: Switch back to struct platform_driver::remove()

After commit 0edb555a65d1 ("platform: Make platform_driver::remove()
return void") .remove() is (again) the right callback to implement for
platform drivers.

Convert all platform drivers below drivers/tty/serial to use .remove(),
with the eventual goal to drop struct platform_driver::remove_new(). As
.remove() and .remove_new() have the same prototypes, conversion is done
by just changing the structure member name in the driver initializer.

Signed-off-by: Uwe Kleine-König <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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serial: xilinx_uartps: Make cdns_rs485_supported static

The sparse tool complains as follows:

drivers/tty/serial/xilinx_uartps.c:222:21: warning:
symbol 'cdns_rs485_supported' was not declared. Sh

serial: xilinx_uartps: Make cdns_rs485_supported static

The sparse tool complains as follows:

drivers/tty/serial/xilinx_uartps.c:222:21: warning:
symbol 'cdns_rs485_supported' was not declared. Should it be static?

This symbol is not used outside xilinx_uartps.c, so marks it static.

Signed-off-by: Jinjie Ruan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: serial: uartps: Add support for uartps controller reset

Add support for an optional reset for the uartps controller using
the reset driver. If the uartps node contains the "resets" property,
th

tty: serial: uartps: Add support for uartps controller reset

Add support for an optional reset for the uartps controller using
the reset driver. If the uartps node contains the "resets" property,
then cdns_uart_startup performs uartps controller non-pulse out of reset
and reset in exit path.

Signed-off-by: Manikanta Guntupalli <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: serial: switch from circ_buf to kfifo

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 pl

tty: serial: switch from circ_buf to kfifo

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) <[email protected]>
Cc: Al Cooper <[email protected]>
Cc: Matthias Brugger <[email protected]>
Cc: AngeloGioacchino Del Regno <[email protected]>
Cc: Kumaravel Thiagarajan <[email protected]>
Cc: Tharun Kumar P <[email protected]>
Cc: Russell King <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: Richard Genoud <[email protected]>
Cc: Nicolas Ferre <[email protected]>
Cc: Alexandre Belloni <[email protected]>
Cc: Claudiu Beznea <[email protected]>
Cc: Alexander Shiyan <[email protected]>
Cc: Baruch Siach <[email protected]>
Cc: Maciej W. Rozycki <[email protected]>
Cc: Shawn Guo <[email protected]>
Cc: Sascha Hauer <[email protected]>
Cc: Fabio Estevam <[email protected]>
Cc: Neil Armstrong <[email protected]>
Cc: Kevin Hilman <[email protected]>
Cc: Jerome Brunet <[email protected]>
Cc: Martin Blumenstingl <[email protected]>
Cc: Taichi Sugaya <[email protected]>
Cc: Takao Orito <[email protected]>
Cc: Bjorn Andersson <[email protected]>
Cc: Konrad Dybcio <[email protected]>
Cc: Pali Rohár <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Aneesh Kumar K.V <[email protected]>
Cc: Naveen N. Rao <[email protected]>
Cc: Manivannan Sadhasivam <[email protected]>
Cc: Krzysztof Kozlowski <[email protected]>
Cc: Alim Akhtar <[email protected]>
Cc: Laxman Dewangan <[email protected]>
Cc: Thierry Reding <[email protected]>
Cc: Jonathan Hunter <[email protected]>
Cc: Orson Zhai <[email protected]>
Cc: Baolin Wang <[email protected]>
Cc: Chunyan Zhang <[email protected]>
Cc: Patrice Chotard <[email protected]>
Cc: Maxime Coquelin <[email protected]>
Cc: Alexandre Torgue <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Hammer Hsieh <[email protected]>
Cc: Peter Korsgaard <[email protected]>
Cc: Timur Tabi <[email protected]>
Cc: Michal Simek <[email protected]>
Cc: Sumit Semwal <[email protected]>
Cc: Christian König <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: serial: uartps: Add rs485 support to uartps driver

Add rs485 support to uartps driver. Use either rts-gpios or RTS
to control RS485 phy as driver or a receiver.

Signed-off-by: Manikanta Guntup

tty: serial: uartps: Add rs485 support to uartps driver

Add rs485 support to uartps driver. Use either rts-gpios or RTS
to control RS485 phy as driver or a receiver.

Signed-off-by: Manikanta Guntupalli <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: serial: uartps: Relocate cdns_uart_tx_empty to facilitate rs485

Relocate cdns_uart_tx_empty function to avoid prototype statement in
rs485 changes.
Update return check with uart_tx_stopped() in

tty: serial: uartps: Relocate cdns_uart_tx_empty to facilitate rs485

Relocate cdns_uart_tx_empty function to avoid prototype statement in
rs485 changes.
Update return check with uart_tx_stopped() in cdns_uart_handle_tx().

Signed-off-by: Manikanta Guntupalli <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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serial: xilinx_uartps: Fix kernel doc about .remove()'s return code

Since the driver was converted to use .remove_new() the return function
doesn't return a value any more. So remove the obsolete do

serial: xilinx_uartps: Fix kernel doc about .remove()'s return code

Since the driver was converted to use .remove_new() the return function
doesn't return a value any more. So remove the obsolete documentation
about the return value.

Reported-by: Michal Simek <[email protected]>
Signed-off-by: Uwe Kleine-König <[email protected]>
Acked-by: Michal Simek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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serial: xilinx_uartps: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to

serial: xilinx_uartps: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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serial: xilinx_uartps: unset STOPBRK when setting STARTBRK

Zynq UG585 states, in chapter B.33, for XUARTPS_CR_STARTBRK:
It can only be set if STPBRK (Stop transmitter break) is not high

This fixes

serial: xilinx_uartps: unset STOPBRK when setting STARTBRK

Zynq UG585 states, in chapter B.33, for XUARTPS_CR_STARTBRK:
It can only be set if STPBRK (Stop transmitter break) is not high

This fixes tcsendbreak, which otherwise does not actually break.

Signed-Off-By: Julien Malik <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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serial: xilinx_uartps: Use port lock wrappers

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, termi

serial: xilinx_uartps: Use port lock wrappers

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 <[email protected]>
Signed-off-by: John Ogness <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: serial: xilinx_uartps: Do not check for 0 return after calling platform_get_irq()

Since commit a85a6c86c25b ("driver core: platform: Clarify that
IRQ 0 is invalid"), there is no possible for
pl

tty: serial: xilinx_uartps: Do not check for 0 return after calling platform_get_irq()

Since commit a85a6c86c25b ("driver core: platform: Clarify that
IRQ 0 is invalid"), there is no possible for
platform_get_irq() to return 0. Use the return value
from platform_get_irq().

Signed-off-by: Ruan Jinjie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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serial: Make uart_remove_one_port() return void

The return value is only ever used as a return value for remove callbacks
of platform drivers. This return value is ignored by the driver core.
(The o

serial: Make uart_remove_one_port() return void

The return value is only ever used as a return value for remove callbacks
of platform drivers. This return value is ignored by the driver core.
(The only effect is an error message, but uart_remove_one_port() already
emitted one in this case.)

So the return value isn't used at all and uart_remove_one_port() can be
changed to return void without any loss. Also this better matches the
Linux device model as remove functions are not supposed to fail.

Signed-off-by: Uwe Kleine-König <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: serial: xilinx_uartps: use console_is_registered()

It is not reliable to check for CON_ENABLED in order to identify if a
console is registered. Use console_is_registered() instead.

Signed-off-

tty: serial: xilinx_uartps: use console_is_registered()

It is not reliable to check for CON_ENABLED in order to identify if a
console is registered. Use console_is_registered() instead.

Signed-off-by: John Ogness <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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serial: xuartps: Use uart_xmit_advance()

Take advantage of the new uart_xmit_advance() helper.

Signed-off-by: Ilpo Järvinen <[email protected]>
Link: https://lore.kernel.org/r/202210190

serial: xuartps: Use uart_xmit_advance()

Take advantage of the new uart_xmit_advance() helper.

Signed-off-by: Ilpo Järvinen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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serial: Make ->set_termios() old ktermios const

There should be no reason to adjust old ktermios which is going to get
discarded anyway.

Reviewed-by: Andy Shevchenko <[email protected]>
Sig

serial: Make ->set_termios() old ktermios const

There should be no reason to adjust old ktermios which is going to get
discarded anyway.

Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: xilinx_uartps: Check the clk_enable return value

Check the clk_enable return value.
If clocks are not enabled the register accesses could hang the
system so error out instead.

Signed-off-by: S

tty: xilinx_uartps: Check the clk_enable return value

Check the clk_enable return value.
If clocks are not enabled the register accesses could hang the
system so error out instead.

Signed-off-by: Shubhrajyoti Datta <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: xilinx_uartps: Add timeout waiting for loop

There is a potential infinite loop while waiting for the
the TXFULL to deassert. Adds the error message and timeout to
avoid infinite loop if it fail

tty: xilinx_uartps: Add timeout waiting for loop

There is a potential infinite loop while waiting for the
the TXFULL to deassert. Adds the error message and timeout to
avoid infinite loop if it fails to get the TX fifo not full.

Signed-off-by: Shubhrajyoti Datta <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: xilinx_uartps: Prevent writes when the controller is disabled

Prevent writing to the fifo if the controller is disabled.

Signed-off-by: Shubhrajyoti Datta <[email protected]>
Link:

tty: xilinx_uartps: Prevent writes when the controller is disabled

Prevent writing to the fifo if the controller is disabled.

Signed-off-by: Shubhrajyoti Datta <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: xilinx_uartps: Fix the ignore_status

Currently the ignore_status is not considered in the isr.
Add a check to add the ignore_status.

Fixes: 61ec9016988f ("tty/serial: add support for Xilinx PS

tty: xilinx_uartps: Fix the ignore_status

Currently the ignore_status is not considered in the isr.
Add a check to add the ignore_status.

Fixes: 61ec9016988f ("tty/serial: add support for Xilinx PS UART")
Signed-off-by: Shubhrajyoti Datta <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tty: xilinx_uartps: Initialise the read_status_mask

Initialise the read status in probe.
It will be checked in the isr so to have the default values lets initialise
in probe.

Signed-off-by: Shubhra

tty: xilinx_uartps: Initialise the read_status_mask

Initialise the read status in probe.
It will be checked in the isr so to have the default values lets initialise
in probe.

Signed-off-by: Shubhrajyoti Datta <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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