Renesas RZ/N1 SoC features a slightly modified DW UART.

On this SoC, the CPR register value is known but not synthetized in
hardware. We hence need to provide a CPR value in the platform
data. This version of the controller also relies on acting as flow
controller when using DMA, so we need to provide the
"is dma flow controller" quirk.
Co-developed-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NPhil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-10-miquel.raynal@bootlin.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

DW based controllers like the one on Renesas RZ/N1 must be programmed as
flow controllers when using DMA.

* Table 11.45 of the system manual, "Flow Control Combinations", states
  that using UART with DMA requires setting the DMA in the peripheral
  flow controller mode regardless of the direction.

* Chapter 11.6.1.3 of the system manual, "Basic Interface Definitions",
  explains that the burst size in the above case must be configured in
  the peripheral's register DEST/SRC_BURST_SIZE.

Experiments shown that upon Rx timeout, the DMA transaction needed to be
manually cleared as well.
Co-developed-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NPhil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-9-miquel.raynal@bootlin.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: NIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-8-miquel.raynal@bootlin.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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

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: NPhil Edworthy <phil.edworthy@renesas.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NPhil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-5-miquel.raynal@bootlin.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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

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

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

Use if and else instead of if(A) and if (!A) and fix a coding style.
Signed-off-by: NWan Jiabing <wanjiabing@vivo.com>
Link: https://lore.kernel.org/r/20220424091310.98780-1-wanjiabing@vivo.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use if and else instead of if(A) and if (!A).
Reviewed-by: NJiri Slaby <jirislaby@kernel.org>
Signed-off-by: NWan Jiabing <wanjiabing@vivo.com>
Link: https://lore.kernel.org/r/20220426071041.168282-1-wanjiabing@vivo.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add early console support in stm32 uart driver.
Signed-off-by: NAlexandre Torgue <alexandre.torgue@foss.st.com>
Signed-off-by: NValentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20220419085330.1178925-4-valentin.caron@foss.st.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

Rework stm32_usart_console_putchar() function in order to anticipate
the case where the character can never be sent.
Signed-off-by: NValentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20220419085330.1178925-2-valentin.caron@foss.st.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Move receive path flow control character handling to own function.

No functional changes.
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220411094859.10894-2-ilpo.jarvinen@linux.intel.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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

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

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

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: NJiri Slaby <jirislaby@kernel.org>
Signed-off-by: NJunwen Wu <wudaemon@gmail.com>
Link: https://lore.kernel.org/r/20220418153703.97705-1-wudaemon@163.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

No need to initialize the count variable in lpuart_copy_rx_to_tty(),
so let's remove it here.
Reviewed-by: NJiri Slaby <jirislaby@kernel.org>
Signed-off-by: NSherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20220418021844.29591-1-sherry.sun@nxp.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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

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: NJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-6-jslaby@suse.czSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

struct uart_port::membase is declared as a pointer. So it should be
initialized by NULL, not zero constant.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-5-jslaby@suse.czSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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

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: NJiri Slaby <jirislaby@kernel.org>
Signed-off-by: NTom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20220421152505.1531507-1-trix@redhat.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: NNeil Armstrong <narmstrong@baylibre.com>
Signed-off-by: NYu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220422111320.19234-3-yu.tu@amlogic.comSigned-off-by: NGreg 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: NNeil Armstrong <narmstrong@baylibre.com>
Signed-off-by: NYu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220422111320.19234-2-yu.tu@amlogic.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some members of struct icom_port are completely unused or only set and
never read. Remove all those.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-11-jslaby@suse.czSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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

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

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

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

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

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

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