serial: 8250: dw: Move the IO accessors to 8250_dwlib.h

These accessors should be used instead of the regular readl/writel()
helpers. In order to use them also from 8250_dw.c in this directory,
move the helpers to 8250_dwlib.h

There is no functional change.

There is no need for declaring `struct uart_port` or even UPIO_MEM32BE
which both are already included in the 8250_dwlib.h header by 8250.h.

Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-8-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: dw: Introduce an rx_timeout variable in the IRQ path

In a next change we are going to need the same Rx timeout condition as
we already have in the IRQ handling code. Let's just create a boolean to
clarify what this operation does before reusing it.

There is no functional change.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-7-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: dma: Allow driver operations before starting DMA transfers

One situation where this could be used is when configuring the UART
controller to be the DMA flow controller. This is a typical case where
the driver might need to program a few more registers before starting a
DMA transfer. Provide the necessary infrastructure to support this
case.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-6-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: dw: Allow to use a fallback CPR value if not synthesized

DW UART controllers can be synthesized without the CPR register.
In this case, allow to the platform information to provide a CPR value.

Co-developed-by: Phil Edworthy <phil.edworthy@renesas.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-5-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: dw: Move the USR register to pdata

This offset is a good candidate to pdata's because it changes depending
on the vendor implementation. Let's move the usr_reg entry from regular
to pdata. This way we can drop initializing it at run time.

Let's also use a define for it instead of defining only the default
value.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-4-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: dw: Create a generic platform data structure

Use device tree match data rather than multiple calls to
of_device_is_compatible() by introducing a platform data structure and
adding a quirks mask.

Provide a stub to the compatibles without quirks to simplify the
handling of the upcoming changes.

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
[<miquel.raynal@bootlin.com: Minor changes + creation of a real pdata structure]
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-3-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: dw: Move definitions to the shared header

Move the per-device structure and a helper out of the main .c file, into
a shared header as they will both be reused from another .c file.

There is no functional change.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
[miquel.raynal@bootlin.com: Extracted from a bigger change]
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-2-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sysrq: do not omit current cpu when showing backtrace of all active CPUs

The backtrace of current CPU also should be printed as it is active. This
change add stack trace for current CPU and print a hint for idle CPU for
the generic workqueue based printing. (x86 already does this)

Now it looks like below:
[  279.401567] sysrq: Show backtrace of all active CPUs
[  279.407234] sysrq: CPU5:
[  279.407505] Call Trace:
[  279.408789] [<ffffffff8000606c>] dump_backtrace+0x2c/0x3a
[  279.411698] [<ffffffff800060ac>] show_stack+0x32/0x3e
[  279.411809] [<ffffffff80542258>] sysrq_handle_showallcpus+0x4c/0xc6
[  279.411929] [<ffffffff80542f16>] __handle_sysrq+0x106/0x26c
[  279.412034] [<ffffffff805436a8>] write_sysrq_trigger+0x64/0x74
[  279.412139] [<ffffffff8029cd48>] proc_reg_write+0x8e/0xe2
[  279.412252] [<ffffffff8021a8f8>] vfs_write+0x90/0x2be
[  279.412362] [<ffffffff8021acd2>] ksys_write+0xa6/0xce
[  279.412467] [<ffffffff8021ad24>] sys_write+0x2a/0x38
[  279.412689] [<ffffffff80003ff8>] ret_from_syscall+0x0/0x2
[  279.417173] sysrq: CPU6: backtrace skipped as idling
[  279.417185] sysrq: CPU4: backtrace skipped as idling
[  279.417187] sysrq: CPU0: backtrace skipped as idling
[  279.417181] sysrq: CPU7: backtrace skipped as idling
[  279.417190] sysrq: CPU1: backtrace skipped as idling
[  279.417193] sysrq: CPU3: backtrace skipped as idling
[  279.417219] sysrq: CPU2:
[  279.419179] Call Trace:
[  279.419440] [<ffffffff8000606c>] dump_backtrace+0x2c/0x3a
[  279.419782] [<ffffffff800060ac>] show_stack+0x32/0x3e
[  279.420015] [<ffffffff80542b30>] showacpu+0x5c/0x96
[  279.420317] [<ffffffff800ba71c>] flush_smp_call_function_queue+0xd6/0x218
[  279.420569] [<ffffffff800bb438>] generic_smp_call_function_single_interrupt+0x14/0x1c
[  279.420798] [<ffffffff800079ae>] handle_IPI+0xaa/0x13a
[  279.421024] [<ffffffff804dcb92>] riscv_intc_irq+0x56/0x70
[  279.421274] [<ffffffff80a05b70>] generic_handle_arch_irq+0x6a/0xfa
[  279.421518] [<ffffffff80004006>] ret_from_exception+0x0/0x10
[  279.421750] [<ffffffff80096492>] rcu_idle_enter+0x16/0x1e

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Link: https://lore.kernel.org/r/20220117154300.2808-1-changbin.du@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: hvcs: simplify if-if to if-else

Use if and else instead of if(A) and if (!A) and fix a coding style.

Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Link: https://lore.kernel.org/r/20220424091310.98780-1-wanjiabing@vivo.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty/hvc_opal: simplify if-if to if-else

Use if and else instead of if(A) and if (!A).

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Link: https://lore.kernel.org/r/20220426071041.168282-1-wanjiabing@vivo.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: stm32: add earlycon support

Add early console support in stm32 uart driver.

Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20220419085330.1178925-4-valentin.caron@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: stm32: add KGDB support

Add support for KGDB in stm32 serial driver by implementing characters
polling callbacks (poll_init, poll_get_char and poll_put_char).

Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Signed-off-by: Jean Philippe Romain <jean-philippe.romain@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20220419085330.1178925-3-valentin.caron@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: stm32: remove infinite loop possibility in putchar function

Rework stm32_usart_console_putchar() function in order to anticipate
the case where the character can never be sent.

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20220419085330.1178925-2-valentin.caron@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: Add function for handling flow control chars

Move receive path flow control character handling to own function.

No functional changes.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220411094859.10894-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: core: fix tcdrain() with CTS enabled

Do not set timeout to twice the approximate amount of time to send the
entire FIFO if CTS is enabled. If the caller requested no timeout, e.g.
when userspace program called tcdrain(), then wait without any timeout.

Premature return from tcdrain() was observed on imx based system which
has 32 character long transmitter FIFO with hardware CTS handling.

Simple userspace application that reproduces problem has to:
  * Open tty device, enable hardware flow control (CRTSCTS)
  * Write data, e.g. 26 bytes
  * Call tcdrain() to wait for the transmitter
  * Close tty device

The other side of serial connection has to:
  * Receive some data, e.g. 10 bytes
  * Set RTS output (CTS input from sender perspective) inactive for
    at least twice the port timeout
  * Try to receive remaining data

Without this patch, userspace application will finish without any error
while the other side of connection will never receive remaining data.

Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220228054911.1420221-1-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

char: ttyprintk: register console

Register a console in the ttyprintk driver so that it can be selected
for /dev/console with console=ttyprintk on the kernel command line,
similar to other console drivers.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Link: https://lore.kernel.org/r/20220215141750.92808-1-vincent.whitchurch@axis.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial/8250: Use fifo in 8250 console driver

Note: I am using a small test app + driver located at [0] for the
problem description. serco is a driver whose write function dispatches
to the serial controller. sertest is a user-mode app that writes n bytes
to the serial console using the serco driver.

While investigating a bug in the RHEL kernel, I noticed that the serial
console throughput is way below the configured speed of 115200 bps in
a HP Proliant DL380 Gen9. I was expecting something above 10KB/s, but
I got 2.5KB/s.

$ time ./sertest -n 2500 /tmp/serco

real    0m0.997s
user    0m0.000s
sys     0m0.997s

With the help of the function tracer, I then noticed the serial
controller was taking around 410us seconds to dispatch one single byte:

$ trace-cmd record -p function_graph -g serial8250_console_write \
   ./sertest -n 1 /tmp/serco

$ trace-cmd report

            |  serial8250_console_write() {
 0.384 us   |    _raw_spin_lock_irqsave();
 1.836 us   |    io_serial_in();
 1.667 us   |    io_serial_out();
            |    uart_console_write() {
            |      serial8250_console_putchar() {
            |        wait_for_xmitr() {
 1.870 us   |          io_serial_in();
 2.238 us   |        }
 1.737 us   |        io_serial_out();
 4.318 us   |      }
 4.675 us   |    }
            |    wait_for_xmitr() {
 1.635 us   |      io_serial_in();
            |      __const_udelay() {
 1.125 us   |        delay_tsc();
 1.429 us   |      }
...
...
...
 1.683 us   |      io_serial_in();
            |      __const_udelay() {
 1.248 us   |        delay_tsc();
 1.486 us   |      }
 1.671 us   |      io_serial_in();
 411.342 us |    }

In another machine, I measured a throughput of 11.5KB/s, with the serial
controller taking between 80-90us to send each byte. That matches the
expected throughput for a configuration of 115200 bps.

This patch changes the serial8250_console_write to use the 16550 fifo
if available. In my benchmarks I got around 25% improvement in the slow
machine, and no performance penalty in the fast machine.

Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Link: https://lore.kernel.org/r/20220411174841.34936-2-wander@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers: tty: serial: Fix deadlock in sa1100_set_termios()

There is a deadlock in sa1100_set_termios(), which is shown
below:

   (Thread 1)              |      (Thread 2)
                           | sa1100_enable_ms()
sa1100_set_termios()       |  mod_timer()
 spin_lock_irqsave() //(1) |  (wait a time)
 ...                       | sa1100_timeout()
 del_timer_sync()          |  spin_lock_irqsave() //(2)
 (wait timer to stop)      |  ...

We hold sport->port.lock in position (1) of thread 1 and
use del_timer_sync() to wait timer to stop, but timer handler
also need sport->port.lock in position (2) of thread 2. As a result,
sa1100_set_termios() will block forever.

This patch moves del_timer_sync() before spin_lock_irqsave()
in order to prevent the deadlock.

Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Link: https://lore.kernel.org/r/20220417111626.7802-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty/sysrq: change the definition of sysrq_key_table's element to make it more readable

The definition of sysrq_key_table's elements, like sysrq_thaw_op and
sysrq_showallcpus_op are not consistent with sysrq_ftrace_dump_op,
Consistency makes code more readable.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Junwen Wu <wudaemon@gmail.com>
Link: https://lore.kernel.org/r/20220418153703.97705-1-wudaemon@163.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: fsl_lpuart: remove the count initialization as it is not needed

No need to initialize the count variable in lpuart_copy_rx_to_tty(),
so let's remove it here.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20220418021844.29591-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: allow COMPILE_TEST for some drivers

Some more serial drivers can be compile-tested under certain
circumstances (when building a specific architecture). So allow for
that.

This reduces the need of zillion mach/subarch-specific configs. And
since the 0day bot has only allmodconfig's for some archs, this
increases build coverage there too.

Note that cpm needs a minor update in the header, so that it drags in
at least some defines (CPM2 ones).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: pic32: make SERIAL_PIC32_CONSOLE depend on SERIAL_PIC32=y

pic32_uart contains this:
  #ifdef CONFIG_SERIAL_PIC32_CONSOLE
  ...
  console_initcall(pic32_console_init);
  ...
  core_initcall(pic32_late_console_init);
  ...
  #endif
  ...
  arch_initcall(pic32_uart_init);

When the driver is built as module, all three above become
module_init(). So if SERIAL_PIC32_CONSOLE is set while SERIAL_PIC32=m,
it results in the following build error:
  In file included from include/linux/device/driver.h:21,
                   from include/linux/device.h:32,
                   from include/linux/platform_device.h:13,
                   from drivers/tty/serial/pic32_uart.c:12:
  include/linux/module.h:131:49: error: redefinition of '__inittest'

So make sure SERIAL_PIC32_CONSOLE can be set only when SERIAL_PIC32=y --
similar as for other drivers.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: qcom: use check for empty instead of pending

The code wants to know if the circ buffer is empty, so use the proper
macro.

No functional change intended, just saner function name used for that
use case.

Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: zs: use NULL as a pointer, not 0

struct uart_port::membase is declared as a pointer. So it should be
initialized by NULL, not zero constant.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: xilinx_uartps: cache xmit in cdns_uart_handle_tx()

Cache port->state->xmit into a local variable (xmit) in
cdns_uart_handle_tx(). This reduces length of some lines there
significantly. I.e. makes the code more readable.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: xilinx_uartps: return early in cdns_uart_handle_tx()

Return from the true branch of the 'if'. This saves one indentation
level and makes the code more readable.

The two comments about what obvious code does are removed too.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: sunplus-uart: change sunplus_console_ports from global to static

Smatch reports this issue
sunplus-uart.c:501:26: warning: symbol 'sunplus_console_ports' was not declared. Should it be static?

sunplus_console_ports is only used in sunplus-uart.c so change
its storage-class specifier to static

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20220421152505.1531507-1-trix@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: meson: Added S4 SOC compatibility

Make UART driver compatible with S4 SOC UART. Meanwhile, the S4 SOC
UART uses 12MHz as the clock source for baud rate calculations.

Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220422111320.19234-3-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: meson: Add a 12MHz internal clock rate to calculate baud rate in order to meet the baud rate requirements of special BT modules

A /2 divider over XTAL was introduced since G12A, and is preferred
to be used over the still present /3 divider since it provides much
closer frequencies vs the request baudrate. Especially the BT module
uses 3Mhz baud rate. 8Mhz calculations can lead to baud rate bias,
causing some problems.

Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220422111320.19234-2-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: icom: remove unused struct icom_port members

Some members of struct icom_port are completely unused or only set and
never read. Remove all those.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-11-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: icom: delete empty serial hooks

uart_ops::release_port() and uart_ops::request_port() are not required
by the serial layer. So no need to define empty ones.

Remove them.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-10-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: icom: use list_for_each_entry()

Use list_for_each_entry() helper instead of explicit combo of
list_for_each() and list_entry().

Note that pos is used as a reference point in list_add_tail() in
icom_alloc_adapter(). This functionality remains as with an empty list,
cur_adapter_entry->icom_adapter_entry is still the list head.

This simplifies the code a bit.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: icom: make icom_acfg_baud const and unsigned

The baud rates are unsigned constants. So mark them as such.

Not only it makes sense, but they are passed also to
uart_get_baud_rate() and that expects unsigned int as baud rates on
input.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: icom: use ARRAY_SIZE

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: icom: move header content to .c

There is no point keeping the header content separated. The header was
not even protected against double inclusion. So move the content to the
appropriate source file.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: icom: use proper __le types and functions

There is a lot of sparse warnings:
  .../icom.c:228:30: warning: cast from restricted __le16
  .../icom.c:232:66: warning: incorrect type in assignment (different base types)
  .../icom.c:232:66:    expected unsigned int [usertype] leBuffer
  .../icom.c:232:66:    got restricted __le32 [usertype]
  .../icom.c:237:30: warning: cast from restricted __le16
  ...
  .../icom.c:1228:22: warning: cast from restricted __le16

And they are correct. So sort them all out by using proper __leXX and
uXX types and the right direction of conversion: le16_to_cpu() instead
of cpu_to_le16(), where appropriate.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: icom: remove to_icom_adapter() and icom_kref_release()

Integrate both the to_icom_adapter() macro and icom_kref_release()
wrapper into icom_remove_adapter(). (And keep it icom_kref_release()
name.)

It makes the code easier to follow without complex indirections.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: icom: switch vague casts to container_of

In icom, there is an ICOM_PORT macro to perform upcasts from struct
uart_port to struct icom_port. It's not completely safe and it works
only because the first member of icom_port is uart_port. Nowadays, we
use container_of for such an upcast instead.

So introduce a helper (to_icom_port()) with container_of in it and
convert all the ICOM_PORT users to the new helper. Apart from the code
and type safety, it's also clear what icom_port (the variable) is.
Unlike with the old ICOM_PORT (the macro with the cast).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: icom: remove ICOM_VERSION_STR macro

It's unused, so remove the macro.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

MAINTAINERS: fix location of moxa-smartio.rst

The moxa-smartio.rst file was moved to a different location,
so update the MAINTAINERS file entry for it.

Quietens one build warning:

MAINTAINERS:29715: WARNING: unknown document: ../driver-api/serial/moxa-smartio

Fixes: 5b437ae9fcbb ("Documentation: tty: move moxa-smartio.rst to tty")
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20220420235545.17081-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: n_gsm: clean up implicit CR bit encoding in address field

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.2.1.2 describes the encoding of the
address field within the frame header. It is made up of the DLCI address,
command/response (CR) bit and EA bit.
Use the predefined CR value instead of a plain 2 in alignment to the
remaining code and to make the encoding obvious.

Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220420101346.3315-3-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: n_gsm: clean up dead code in gsm_queue()

Remove commented out code as it is never used and if anyone accidentally
turned it on, it would be broken.

Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220420101346.3315-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Revert "serial: 8250: Handle UART without interrupt on TEMT using em485"

This partially reverts commit f6f586102add. The code added by
that commit containted math overflow for 32-bit archs. In
addition, the approach used in it is unnecessarily complicated
requiring a dedicated timer just for notemt. A simpler approach
for providing UART_CAP_NOTEMT already exists (patches 1-2):
  https://lore.kernel.org/linux-serial/20220411083321.9131-3-ilpo.jarvinen@linux.intel.com/T/#u
Thus, simply revert the UART_CAP_NOTEMT change for now.

There were two driver changes within the patch series adding
UART_CAP_NOTEMT taking advantage of the newly added flag.
This does not revert the driver changes and therefore also
UART_CAP_NOTEMT define has to remain. UART_CAP_NOTEMT remains
no-op until support is again added.

Fixes: f6f586102add ("serial: 8250: Handle UART without interrupt on TEMT using em485")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/5f874142-fb1f-bff7-f33-fac823e65e2e@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation: fix tty link

The commit below causes the following warnings:
Documentation/driver-api/index.rst:14: WARNING: toctree contains reference to nonexisting document 'driver-api/tty'
Documentation/driver-api/tty/index.rst: WARNING: document isn't included in any toctree

This is because I omitted the "/index" part from the link. That part is
needed for directories and I was confused by the surrounding links which
are links to files. Fix it in this patch.

Fixes: b96cd8b05ead ("Documentation: move tty to driver-api")
Cc: Jonathan Corbet <corbet@lwn.net>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220419074302.29632-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: fsl_lpuart: fix potential bug when using both of_alias_get_id and ida_simple_get

Now fsl_lpuart driver use both of_alias_get_id() and ida_simple_get() in
.probe(), which has the potential bug. For example, when remove the
lpuart7 alias in dts, of_alias_get_id() will return error, then call
ida_simple_get() to allocate the id 0 for lpuart7, this may confilct
with the lpuart4 which has alias 0.

    aliases {
...
        serial0 = &lpuart4;
        serial1 = &lpuart5;
        serial2 = &lpuart6;
        serial3 = &lpuart7;
    }

So remove the ida_simple_get() in .probe(), return an error directly
when calling of_alias_get_id() fails, which is consistent with other
uart drivers behavior.

Fixes: 3bc3206e1c0f ("serial: fsl_lpuart: Remove the alias node dependence")
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20220321112211.8895-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: When UART is suspended, set RTS to false

When flow control is enabled, the UART should set RTS to false
during suspend to stop incoming data. Currently, the suspend
routine sets the mctrl register in the uart to zero, but leaves
the shadow version in the uart_port struct alone so that resume
can restore it. This causes a problem later in suspend when
serial8250_do_shutdown() is called which uses the shadow mctrl
register to clear some additional bits but ends up restoring RTS.
The solution is to clear RTS from the shadow version before
serial8250_do_shutdown() is called and restore it after.

Signed-off-by: Al Cooper <alcooperx@comcast.net>
Link: https://lore.kernel.org/r/20220324145620.41573-1-alcooperx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: add compatible for fsl,16550-FIFO64

Signed-off-by: Eric Tremblay <etremblay@distech-controls.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220330104642.229507-4-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: Add UART_CAP_NOTEMT on PORT_16550A_FSL64

The Freescale variant of the 16550A doesn't have an interrupt on TEMT
available when using the FIFO mode.

Signed-off-by: Eric Tremblay <etremblay@distech-controls.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220330104642.229507-3-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: Handle UART without interrupt on TEMT using em485

Introduce the UART_CAP_NOTEMT capability. The capability indicates that
the UART doesn't have an interrupt available on TEMT.

In the case where the device does not support it, we calculate the
maximum time it could take for the transmitter to empty the
shift register. When we get in the situation where we get the
THRE interrupt, we check if the TEMT bit is set. If it's not, we start
the a timer and recall __stop_tx() after the delay.

The transmit sequence is a bit modified when the capability is set. The
new timer is used between the last interrupt(THRE) and a potential
stop_tx timer.

Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com>
[moved to use added UART_CAP_TEMT]
Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
[moved to use added UART_CAP_NOTEMT, improve timeout]
Signed-off-by: Eric Tremblay <etremblay@distech-controls.com>
[rebased to v5.17, making use of tty_get_frame_size]
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220330104642.229507-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250_aspeed_vuart: Fix potential NULL dereference in aspeed_vuart_probe

platform_get_resource() may fail and return NULL, so we should
better check it's return value to avoid a NULL pointer dereference.

Fixes: 54da3e381c2b ("serial: 8250_aspeed_vuart: use UPF_IOREMAP to set up register mapping")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220404143842.16960-1-linmq006@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: atmel: remove redundant assignment in rs485_config

In uart_set_rs485_config() the serial core already assigns the passed
serial_rs485 struct to the uart port.

So remove the assignment from the drivers rs485_config() function to avoid
redundancy.

Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-10-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: fsl_lpuart: remove redundant code in rs485_config functions

In uart_set_rs485_config() the serial core already ensures that only one of
both options RTS on send or RTS after send is set. It also assigns the
passed serial_rs485 struct to the uart port.

So remove the check and the assignment from the drivers rs485_config()
function to avoid redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-9-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: imx: remove redundant assignment in rs485_config

In uart_set_rs485_config() the serial core already assigns the passed
serial_rs485 struct to the uart port.

So remove the assignment in the drivers rs485_config() function to avoid
reduncancy.

Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-8-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: max310: remove redundant memset in rs485_config

In uart_set_rs485_config() the serial core already nullifies the padding
field of the passed serial_rs485 struct before returning it to userspace.

Doing the same in the drivers rs485_config() function is redundant, so
remove the concerning memset in this function.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-7-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: omap: remove redundant code in rs485_config

In uart_set_rs485_config() the serial core already clamps the RTS delays.
It also assigns the passed serial_rs485 struct to the uart port.

So remove these tasks from the drivers rs485_config() function to avoid
redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-6-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: sc16is7xx: remove redundant check in rs485_config

In uart_set_rs485_config() the serial core already ensures that only one of
both options RTS on send or RTS after send is set.

So remove this check from the drivers rs485_config() function to avoid
redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-5-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: stm32: remove redundant code in rs485_config

In uart_set_rs485_config() the serial core already ensures that only one of
both options RTS on send or RTS after send is set. It also assigns the
passed serial_rs485 struct to the uart port.

So remove the check and the assignment from the drivers rs485_config()
function to avoid redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-4-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: amba-pl011: remove redundant code in rs485_config

In uart_set_rs485_config() the serial core already

- ensures that only one of both options RTS on send or RTS after send is
  set

- nullifies the padding field of the passed serial_rs485 struct

- clamps the RTS delays

- assigns the passed serial_rs485 struct to the uart port

So remove these tasks from the code of the drivers rs485_config() function
to avoid redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-3-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: core: move RS485 configuration tasks from drivers into core

Several drivers that support setting the RS485 configuration via userspace
implement one or more of the following tasks:

- in case of an invalid RTS configuration (both RTS after send and RTS on
  send set or both unset) fall back to enable RTS on send and disable RTS
  after send

- nullify the padding field of the returned serial_rs485 struct

- copy the configuration into the uart port struct

- limit RTS delays to 100 ms

Move these tasks into the serial core to make them generic and to provide
a consistent behaviour among all drivers.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-2-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: meson: Use DIV_ROUND_CLOSEST to calculate baud rates

Due to chip process differences, chip designers recommend using baud
rates as close to and larger as possible in order to reduce clock
errors.

Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20220407081355.13602-2-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dt-bindings: serial: Update Qualcomm geni based QUP UART bindings

Similar to I2C controller, move geni based QUP UART controller binding
out from parent schema to an individual binding and let parent refer to
child schema later on. UART binding also stand incomplete right now
similar to I2C, complete it along this process.

Signed-off-by: Kuldeep Singh <singh.kuldeep87k@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220404182938.29492-4-singh.kuldeep87k@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: Report which option to enable for blacklisted PCI devices

Provide information in the kernel log as to what configuration option to
enable for PCI UART devices that have been blacklisted in the generic
PCI 8250 UART driver and which have a dedicated driver available to
handle that has been disabled.  The rationale is there is no easy way
for the user to map a specific PCI vendor:device pair to an individual
dedicated driver while the generic driver has this information readily
available and it will likely be confusing that the generic driver does
not register such a port.

This is unlike usual drivers, such as drivers/net/ethernet/3com/3c59x.c
which handles all the hardware family members regardless of differences
between them, and following an existing example where a serio driver
provides suggestions as to the correct configuration options to use:

psmouse serio1: synaptics: The touchpad can support a better bus than the too old PS/2 protocol. Make sure MOUSE_PS2_SYNAPTICS_SMBUS and RMI4_SMB are enabled to get a better touchpad experience.

A message is then printed like:

serial 0000:04:00.3: ignoring port, enable SERIAL_8250_PERICOM to handle

when an affected device is encountered and the generic driver rejects it.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2203310054120.44113@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: n_tty: Restore EOF push handling behavior

TTYs in ICANON mode have a special case that allows "pushing" a line
without a regular EOL character (like newline), by using EOF (the EOT
character - ASCII 0x4) as a pseudo-EOL. It is silently discarded, so
the reader of the PTS will receive the line *without* EOF or any other
terminating character.

This special case has an edge case: What happens if the readers buffer
is the same size as the line (without EOF)? Will they be able to tell
if the whole line is received, i.e. if the next read() will return more
of the same line or the next line?

There are two possibilities,  that both have (dis)advantages:

1. The next read() returns 0. FreeBSD (13.0) and OSX (10.11) do this.
   Advantage: The reader can interpret this as "the line is over".
   Disadvantage: read() returning 0 means EOF, the reader could also
   interpret it as "there's no more data" and stop reading or even
   close the PT.

2. The next read() returns the next line, the EOF is silently discarded.
   Solaris (or at least OpenIndiana 2021.10) does this, Linux has done
   do this since commit 40d5e0905a03 ("n_tty: Fix EOF push handling");
   this behavior was recently broken by commit 359303076163 ("tty:
   n_tty: do not look ahead for EOL character past the end of the buffer").
   Advantage: read() won't return 0 (EOF), reader less likely to be
   confused (and things like `while(read(..)>0)` don't break)
   Disadvantage: The reader can't really know if the read() continues
   the last line (that filled the whole read buffer) or starts a
   new line.

As both options are defensible (and are used by other Unix-likes), it's
best to stick to the "old" behavior since "n_tty: Fix EOF push handling"
of 2013, i.e. silently discard that EOF.

This patch - that I actually got from Linus for testing and only
modified slightly - restores that behavior by skipping an EOF
character if it's the next character after reading is done.

Based on a patch from Linus Torvalds.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215611
Fixes: 359303076163 ("tty: n_tty: do not look ahead for EOL character past the end of the buffer")
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Reviewed-and-tested-by: Daniel Gibson <daniel@gibson.sh>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Daniel Gibson <daniel@gibson.sh>
Link: https://lore.kernel.org/r/20220329235810.452513-2-daniel@gibson.sh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

serial: 8250: Make SERIAL_8250_EM available for arm64 systems

This is needed for the Renesas RZ/V2M (r9a09g011) SoC.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220330154024.112270-6-phil.edworthy@renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dt-bindings: serial: renesas,em-uart: Document r9a09g011 bindings

The Renesas RZ/V2M (r9a09g011) SoC uses a uart that is compatible with the
EMMA Mobile SoC.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20220330154024.112270-3-phil.edworthy@renesas.com
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dt-bindings: serial: fsl-lpuart: Add imx93 compatible string

The lpuart on i.MX93 is derived from i.MX7ULP with some industrial
enhancements, it uses two compatible strings, so update the
compatible string for i.MX93.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20220323093659.1722463-1-peng.fan@oss.nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dt-bindings: serial: uniphier: Add "resets" property as optional

UniPhier UART controller has a reset lines from system controller.
Add "resets" property to fix the following warning.

  uniphier-ld11-global.dtb: serial@54006800: 'resets' does not match any of the regexes: 'pinctrl-[0-9]+'
      From schema: Documentation/devicetree/bindings/serial/socionext,uniphier-uart.yaml

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Link: https://lore.kernel.org/r/1648617338-8600-3-git-send-email-hayashi.kunihiko@socionext.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dt-bindings: serial: uniphier: Use maxItems for a single clock

'maxItems' is preferred for a single entry, not 'minItems'.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Link: https://lore.kernel.org/r/1648617338-8600-2-git-send-email-hayashi.kunihiko@socionext.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: owl: Fix missing clk_disable_unprepare() in owl_uart_probe

Fix the missing clk_disable_unprepare() before return
from owl_uart_probe() in the error handling case.

Fixes: abf42d2f333b ("tty: serial: owl: add "much needed" clk_prepare_enable()")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220307105135.11698-1-linmq006@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: samsung: add spin_lock for interrupt and console_write

The console_write and IRQ handler can run concurrently.
Problems may occurs console_write is continuously executed while
the IRQ handler is running.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
Link: https://lore.kernel.org/r/20220407071619.102249-2-jaewon02.kim@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: Fix a possible resource leak in icom_probe

When pci_read_config_dword failed, call pci_release_regions() and
pci_disable_device() to recycle the resource previously allocated.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Huang Guobin <huangguobin4@huawei.com>
Link: https://lore.kernel.org/r/20220331091005.3290753-1-huangguobin4@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: Prepare cleanup of powerpc's asm/prom.h

powerpc's asm/prom.h brings some headers that it doesn't
need itself.

In order to clean it up, first add missing headers in
users of asm/prom.h

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/49fc0d4b6446da630b1e9f29c4bab38f8ed087bf.1648833419.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: hvc: Prepare cleanup of powerpc's asm/prom.h

powerpc's asm/prom.h brings some headers that it doesn't
need itself.

In order to clean it up, first add missing headers in
users of asm/prom.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/8b3dbd25bbeb7949e1b0a2170fee7b9cc5a6f806.1648833418.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: goldfish: Use tty_port_destroy() to destroy port

In goldfish_tty_probe(), the port initialized through tty_port_init()
should be destroyed in error paths.In goldfish_tty_remove(), qtty->port
also should be destroyed or else might leak resources.

Fix the above by calling tty_port_destroy().

Fixes: 666b7793d4bf ("goldfish: tty driver")
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Wang Weiyang <wangweiyang2@huawei.com>
Link: https://lore.kernel.org/r/20220328115844.86032-1-wangweiyang2@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: altera: use altera_jtaguart_stop_tx()

altera_jtaguart_tx_chars() duplicates what altera_jtaguart_stop_tx()
already does. So instead of the duplication, call the helper instead.

Not only it makes the code cleaner, but it also says what the "if"
really does.

Cc: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411104506.8990-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: owl-uart, send x_char even if stopped

Flow control characters should be sent even if the TX is stopped. So fix
owl-uart to behave the same as other drivers.

This unification also allows the use of the TX helper in the future.

Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411104506.8990-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: serial: mpc52xx_uart: remove double ifdeffery

The code now contains:
 #ifdef CONFIG_PPC_MPC512x
 ...
 #endif

 #ifdef CONFIG_PPC_MPC512x
 ...
 #endif

So remove the endif+ifdef from the middle, provided it's about the same
define.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411104506.8990-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: synclink_gt: Fix null-pointer-dereference in slgt_clean()

When the driver fails at alloc_hdlcdev(), and then we remove the driver
module, we will get the following splat:

[   25.065966] general protection fault, probably for non-canonical address 0xdffffc0000000182: 0000 [#1] PREEMPT SMP KASAN PTI
[   25.066914] KASAN: null-ptr-deref in range [0x0000000000000c10-0x0000000000000c17]
[   25.069262] RIP: 0010:detach_hdlc_protocol+0x2a/0x3e0
[   25.077709] Call Trace:
[   25.077924]  <TASK>
[   25.078108]  unregister_hdlc_device+0x16/0x30
[   25.078481]  slgt_cleanup+0x157/0x9f0 [synclink_gt]

Fix this by checking whether the 'info->netdev' is a null pointer first.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Link: https://lore.kernel.org/r/20220410114814.3920474-1-zheyuma97@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation: tty: n_gsm, use power of ReST

Reformat the whole document, so that automatic numbering and TOC is
properly generated.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411110143.10019-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation: tty: n_gsm, delete "Additional Documentation"

All of the URLs give 404. There is a little point to preserve them. If
really need be, we could try archive.org if the documents are not there
by a chance.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411110143.10019-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation: tty: move moxa-smartio.rst to tty

It is a tty_driver, not serial -- uart_driver. So move it to the tty
docs dir too. (The same as the driver itself.)

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411110143.10019-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation: tty: move n_gsm to tty

We have n_tty documented in Documentation/driver-api/tty/. n_gsm belongs
there too, so move from serial/ to tty/ too.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411110143.10019-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation: tty: introduce "Other Documentation"

So far only n_tty belongs here, but in the next patches, more will come.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411110143.10019-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation: move tty to driver-api

Based on discussion starting as 87mthw2o93.fsf@meer.lwn.net, let's move
the tty documentation to driver-api. It's more appropriate there.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411110143.10019-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Linux 5.18-rc2

Merge tag 'tty-5.18-rc2' of git://git./linux/kernel/git/gregkh/tty

Pull serial driver fix from Greg KH:
 "This is a single serial driver fix for a build issue that showed up
  due to changes that came in through the tty tree in 5.18-rc1 that were
  missed previously. It resolves a build error with the mpc52xx_uart
  driver.

  It has been in linux-next this week with no reported problems"

* tag 'tty-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: serial: mpc52xx_uart: make rx/tx hooks return unsigned, part II.

Merge tag 'staging-5.18-rc2' of git://git./linux/kernel/git/gregkh/staging

Pull staging driver fix from Greg KH:
 "Here is a single staging driver fix for 5.18-rc2 that resolves an
  endian issue for the r8188eu driver. It has been in linux-next all
  this week with no reported problems"

* tag 'staging-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: r8188eu: Fix PPPoE tag insertion on little endian systems

Merge tag 'driver-core-5.18-rc2' of git://git./linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here are two small driver core changes for 5.18-rc2.

  They are the final bits in the removal of the default_attrs field in
  struct kobj_type. I had to wait until after 5.18-rc1 for all of the
  changes to do this came in through different development trees, and
  then one new user snuck in. So this series has two changes:

   - removal of the default_attrs field in the powerpc/pseries/vas code.

     The change has been acked by the PPC maintainers to come through
     this tree

   - removal of default_attrs from struct kobj_type now that all
     in-kernel users are removed.

     This cleans up the kobject code a little bit and removes some
     duplicated functionality that confused people (now there is only
     one way to do default groups)

  Both of these have been in linux-next for all of this week with no
  reported problems"

* tag 'driver-core-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kobject: kobj_type: remove default_attrs
  powerpc/pseries/vas: use default_groups in kobj_type

Merge tag 'char-misc-5.18-rc2' of git://git./linux/kernel/git/gregkh/char-misc

Pull char/misc driver fix from Greg KH:
 "A single driver fix. It resolves the build warning issue on 32bit
  systems in the habannalabs driver that came in during the 5.18-rc1
  merge cycle.

  It has been in linux-next for all this week with no reported problems"

* tag 'char-misc-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  habanalabs: Fix test build failures

Merge tag 'powerpc-5.18-2' of git://git./linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:

 - Fix KVM "lost kick" race, where an attempt to pull a vcpu out of the
   guest could be lost (or delayed until the next guest exit).

 - Disable SCV (system call vectored) when PR KVM guests could be run.

 - Fix KVM PR guests using SCV, by disallowing AIL != 0 for KVM PR
   guests.

 - Add a new KVM CAP to indicate if AIL == 3 is supported.

 - Fix a regression when hotplugging a CPU to a memoryless/cpuless node.

 - Make virt_addr_valid() stricter for 64-bit Book3E & 32-bit, which
   fixes crashes seen due to hardened usercopy.

 - Revert a change to max_mapnr which broke HIGHMEM.

Thanks to Christophe Leroy, Fabiano Rosas, Kefeng Wang, Nicholas Piggin,
and Srikar Dronamraju.

* tag 'powerpc-5.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  Revert "powerpc: Set max_mapnr correctly"
  powerpc: Fix virt_addr_valid() for 64-bit Book3E & 32-bit
  KVM: PPC: Move kvmhv_on_pseries() into kvm_ppc.h
  powerpc/numa: Handle partially initialized numa nodes
  powerpc/64: Fix build failure with allyesconfig in book3s_64_entry.S
  KVM: PPC: Use KVM_CAP_PPC_AIL_MODE_3
  KVM: PPC: Book3S PR: Disallow AIL != 0
  KVM: PPC: Book3S PR: Disable SCV when AIL could be disabled
  KVM: PPC: Book3S HV P9: Fix "lost kick" race

Merge tag 'irq-urgent-2022-04-10' of git://git./linux/kernel/git/tip/tip

Pull irq fixes from Thomas Gleixner:
 "A set of interrupt chip driver fixes:

   - A fix for a long standing bug in the ARM GICv3 redistributor
     polling which uses the wrong bit number to test.

   - Prevent translation of bogus ACPI table entries which map device
     interrupts into the IPI space on ARM GICs.

   - Don't write into the pending register of ARM GICV4 before the scan
     in hardware has completed.

   - A set of build and correctness fixes for the Qualcomm MPM driver"

* tag 'irq-urgent-2022-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic, gic-v3: Prevent GSI to SGI translations
  irqchip/gic-v3: Fix GICR_CTLR.RWP polling
  irqchip/gic-v4: Wait for GICR_VPENDBASER.Dirty to clear before descheduling
  irqchip/irq-qcom-mpm: fix return value check in qcom_mpm_init()
  irq/qcom-mpm: Fix build error without MAILBOX

Merge tag 'x86_urgent_for_v5.18_rc2' of git://git./linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:

 - Fix the MSI message data struct definition

 - Use local labels in the exception table macros to avoid symbol
   conflicts with clang LTO builds

 - A couple of fixes to objtool checking of the relatively newly added
   SLS and IBT code

 - Rename a local var in the WARN* macro machinery to prevent shadowing

* tag 'x86_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/msi: Fix msi message data shadow struct
  x86/extable: Prefer local labels in .set directives
  x86,bpf: Avoid IBT objtool warning
  objtool: Fix SLS validation for kcov tail-call replacement
  objtool: Fix IBT tail-call detection
  x86/bug: Prevent shadowing in __WARN_FLAGS
  x86/mm/tlb: Revert retpoline avoidance approach

Merge tag 'perf_urgent_for_v5.18_rc2' of git://git./linux/kernel/git/tip/tip

Pull perf fixes from Borislav Petkov:

 - A couple of fixes to cgroup-related handling of perf events

 - A couple of fixes to event encoding on Sapphire Rapids

 - Pass event caps of inherited events so that perf doesn't fail wrongly
   at fork()

 - Add support for a new Raptor Lake CPU

* tag 'perf_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Always set cpuctx cgrp when enable cgroup event
  perf/core: Fix perf_cgroup_switch()
  perf/core: Use perf_cgroup_info->active to check if cgroup is active
  perf/core: Don't pass task around when ctx sched in
  perf/x86/intel: Update the FRONTEND MSR mask on Sapphire Rapids
  perf/x86/intel: Don't extend the pseudo-encoding to GP counters
  perf/core: Inherit event_caps
  perf/x86/uncore: Add Raptor Lake uncore support
  perf/x86/msr: Add Raptor Lake CPU support
  perf/x86/cstate: Add Raptor Lake support
  perf/x86: Add Intel Raptor Lake support

Merge tag 'locking_urgent_for_v5.18_rc2' of git://git./linux/kernel/git/tip/tip

Pull locking fixes from Borislav Petkov:

 - Allow the compiler to optimize away unused percpu accesses and change
   the local_lock_* macros back to inline functions

 - A couple of fixes to static call insn patching

* tag 'locking_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "mm/page_alloc: mark pagesets as __maybe_unused"
  Revert "locking/local_lock: Make the empty local_lock_*() function a macro."
  x86/percpu: Remove volatile from arch_raw_cpu_ptr().
  static_call: Remove __DEFINE_STATIC_CALL macro
  static_call: Properly initialise DEFINE_STATIC_CALL_RET0()
  static_call: Don't make __static_call_return0 static
  x86,static_call: Fix __static_call_return0 for i386

Merge tag 'sched_urgent_for_v5.18_rc2' of git://git./linux/kernel/git/tip/tip

Pull scheduler fixes from Borislav Petkov:

 - Use the correct static key checking primitive on the IRQ exit path

 - Two fixes for the new forceidle balancer

* tag 'sched_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  entry: Fix compile error in dynamic_irqentry_exit_cond_resched()
  sched: Teach the forced-newidle balancer about CPU affinity limitation.
  sched/core: Fix forceidle balancing

Merge tag 'perf-tools-fixes-for-v5.18-2022-04-09' of git://git./linux/kernel/git/acme/linux

Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Fix the clang command line option probing and remove some options to
   filter out, fixing the build with the latest clang versions

 - Fix 'perf bench' futex and epoll benchmarks to deal with machines
   with more than 1K CPUs

 - Fix 'perf test tsc' error message when not supported

 - Remap perf ring buffer if there is no space for event, fixing perf
   usage in 32-bit ChromeOS

 - Drop objdump stderr to avoid getting stuck waiting for stdout output
   in 'perf annotate'

 - Fix up garbled output by now showing unwind error messages when
   augmenting frame in best effort mode

 - Fix perf's libperf_print callback, use the va_args eprintf() variant

 - Sync vhost and arm64 cputype headers with the kernel sources

 - Fix 'perf report --mem-mode' with ARM SPE

 - Add missing external commands ('iiostat', etc) to 'perf --list-cmds'

* tag 'perf-tools-fixes-for-v5.18-2022-04-09' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  perf annotate: Drop objdump stderr to avoid getting stuck waiting for stdout output
  perf tools: Add external commands to list-cmds
  perf docs: Add perf-iostat link to manpages
  perf session: Remap buf if there is no space for event
  perf bench: Fix epoll bench to correct usage of affinity for machines with #CPUs > 1K
  perf bench: Fix futex bench to correct usage of affinity for machines with #CPUs > 1K
  perf tools: Fix perf's libperf_print callback
  perf: arm-spe: Fix perf report --mem-mode
  perf unwind: Don't show unwind error messages when augmenting frame pointer stack
  tools headers arm64: Sync arm64's cputype.h with the kernel sources
  perf test tsc: Fix error message when not supported
  perf build: Don't use -ffat-lto-objects in the python feature test when building with clang-13
  perf python: Fix probing for some clang command line options
  tools build: Filter out options and warnings not supported by clang
  tools build: Use $(shell ) instead of `` to get embedded libperl's ccopts
  tools include UAPI: Sync linux/vhost.h with the kernel sources

Merge tag 'cxl+nvdimm-for-5.18-rc2' of git://git./linux/kernel/git/nvdimm/nvdimm

Pull cxl and nvdimm fixes from Dan Williams:

 - Fix a compile error in the nvdimm unit tests

 - Fix a shadowed variable warning in the CXL PCI driver

* tag 'cxl+nvdimm-for-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  cxl/pci: Drop shadowed variable
  tools/testing/nvdimm: Fix security_init() symbol collision

Merge tag 'gpio-fixes-for-v5.18-rc2' of git://git./linux/kernel/git/brgl/linux

Pull gpio fix from Bartosz Golaszewski:

 - fix a race condition with consumers accessing the fields of GPIO IRQ
   chips before they're fully initialized

* tag 'gpio-fixes-for-v5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  gpio: Restrict usage of GPIO chip irq members before initialization

Merge tag 'irqchip-fixes-5.18-1' of git://git./linux/kernel/git/maz/arm-platforms into irq/urgent

Pull irqchip fixes from Marc Zyngier:

 - Fix GICv3 polling for RWP in redistributors

 - Reject ACPI attempts to use SGIs on GIC/GICv3

 - Fix unpredictible behaviour when making a VPE non-resident
   with GICv4

 - A couple of fixes for the newly merged qcom-mpm driver

Link: https://lore.kernel.org/lkml/20220409094229.267649-1-maz@kernel.org

perf annotate: Drop objdump stderr to avoid getting stuck waiting for stdout output

If objdump writes to stderr it can block waiting for it to be read. As
perf doesn't read stderr then progress stops with perf waiting for
stdout output.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Truong <alexandre.truong@arm.com>
Cc: Dave Marchevsky <davemarchevsky@fb.com>
Cc: Denis Nikitin <denik@chromium.org>
Cc: German Gomez <german.gomez@arm.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Lexi Shao <shaolexi@huawei.com>
Cc: Li Huafei <lihuafei1@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Liška <mliska@suse.cz>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Remi Bernon <rbernon@codeweavers.com>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Cc: William Cohen <wcohen@redhat.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20220407230503.1265036-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>