linux.git/drivers/tty/serial/sunsu.c, branch v5.19

tty: remove CMSPAR ifdefs

2022-05-19T16:26:16+00:00

CMSPAR is defined by all architectures since commit 6bf08cb246b5
("[PATCH] Add CMSPAR to termbits.h for powerpc and alpha").

Reviewed-by: Johan Hovold 
Signed-off-by: Ilpo Järvinen 
Link: https://lore.kernel.org/r/20220513082906.11096-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

serial: make uart_console_write->putchar()'s character an unsigned char

2022-03-03T14:06:31+00:00

Currently, uart_console_write->putchar's second parameter (the
character) is of type int. It makes little sense, provided uart_console_write()
accepts the input string as "const char *s" and passes its content -- the
characters -- to putchar(). So switch the character's type to unsigned
char.

We don't use char as that is signed on some platforms. That would cause
troubles for drivers which (implicitly) cast the char to u16 when
writing to the device. Sign extension would happen in that case and the
value written would be completely different to the provided char. DZ is
an example of such a driver -- on MIPS, it uses u16 for dz_out in
dz_console_putchar().

Note we do the char -> uchar conversion implicitly in
uart_console_write(). Provided we do not change size of the data type,
sign extension does not happen there, so the problem is void.

This makes the types consistent and unified with the rest of the uart
layer, which uses unsigned char in most places already. One exception is
xmit_buf, but that is going to be converted later.

Cc: Paul Cercueil 
Cc: Tobias Klauser 
Cc: Russell King 
Cc: Vineet Gupta 
Cc: Nicolas Ferre 
Cc: Alexandre Belloni 
Cc: Ludovic Desroches 
Cc: Florian Fainelli 
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: Alexander Shiyan 
Cc: Baruch Siach 
Cc: "Maciej W. Rozycki" 
Cc: Paul Walmsley 
Cc: Palmer Dabbelt 
Cc: Albert Ou 
Cc: Shawn Guo 
Cc: Sascha Hauer 
Cc: Pengutronix Kernel Team 
Cc: Fabio Estevam 
Cc: NXP Linux Team 
Cc: Karol Gugala 
Cc: Mateusz Holenko 
Cc: Vladimir Zapolskiy 
Cc: Neil Armstrong 
Cc: Kevin Hilman 
Cc: Jerome Brunet 
Cc: Martin Blumenstingl 
Cc: Taichi Sugaya 
Cc: Takao Orito 
Cc: Liviu Dudau 
Cc: Sudeep Holla 
Cc: Lorenzo Pieralisi 
Cc: "Andreas Färber" 
Cc: Manivannan Sadhasivam 
Cc: Michael Ellerman 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Andy Gross 
Cc: Bjorn Andersson 
Cc: Krzysztof Kozlowski 
Cc: Orson Zhai 
Cc: Baolin Wang 
Cc: Chunyan Zhang 
Cc: Patrice Chotard 
Cc: Maxime Coquelin 
Cc: Alexandre Torgue 
Cc: "David S. Miller" 
Cc: Peter Korsgaard 
Cc: Michal Simek 
Acked-by: Richard Genoud  [atmel_serial]
Acked-by: Uwe Kleine-König 
Acked-by: Paul Cercueil 
Acked-by: Neil Armstrong  # meson_serial
Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20220303080831.21783-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman

serial: 8250: Move Alpha-specific quirk out of the core

2021-12-30T12:23:44+00:00

struct uart_8250_port contains mcr_mask and mcr_force members whose
sole purpose is to work around an Alpha-specific quirk.  This code
doesn't belong in the core where it is executed by everyone else,
so move it to a proper ->set_mctrl callback which is used on the
affected Alpha machine only.

The quirk was introduced in January 1995:
https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/diff/drivers/char/serial.c?h=1.1.83

The members in struct uart_8250_port were added in 2002:
https://git.kernel.org/history/history/c/4524aad27854

The quirk applies to non-PCI Alphas and arch/alpha/Kconfig specifies
"select FORCE_PCI if !ALPHA_JENSEN".  So apparently the only affected
machine is the EISA-based Jensen that Linus was working on back then:
https://lore.kernel.org/all/CAHk-=wj1JWZ3sCrGz16nxEj7=0O+srMg6Ah3iPTDXSPKEws_SA@mail.gmail.com/

Up until now the quirk is not applied unless CONFIG_PCI is disabled.
If users forget to do that or run a generic Alpha kernel, the serial
ports aren't usable on Jensen.  Avoid by confining the quirk to
CONFIG_ALPHA_JENSEN instead of !CONFIG_PCI.  On generic Alpha kernels,
auto-detect at runtime whether the quirk needs to be applied.

Cc: Russell King 
Cc: Ulrich Teichert 
Cc: Linus Torvalds 
Signed-off-by: Lukas Wunner 
Link: https://lore.kernel.org/r/b83d069cb516549b8a5420e097bb6bdd806f36fc.1640695609.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman

tty: serial: sunsu: include instead of

2021-05-13T16:29:12+00:00

Include the more general linux/io.h instead of asm/io.h
as checkpatch suggests.

Signed-off-by: Zihao Tang 
Signed-off-by: Jay Fang 
Link: https://lore.kernel.org/r/1620874904-39285-10-git-send-email-f.fangjian@huawei.com
Signed-off-by: Greg Kroah-Hartman

serial: sunsu: drop low-latency workaround

2021-04-22T10:09:26+00:00

The sunsu driver has been carrying a workaround for the infamous
low_latency behaviour of tty_flip_buffer_push() by dropping and
reacquiring the port lock in the interrupt handler since 2004.

Since commit a9c3f68f3cd8 ("tty: Fix low_latency BUG"),
tty_flip_buffer_push() always schedules a work item to push data to the
line discipline and there's no need to keep any low_latency hacks around.

Cc: "David S. Miller" 
Acked-by: David S. Miller 
Signed-off-by: Johan Hovold 
Link: https://lore.kernel.org/r/20210421095509.3024-24-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva

tty/serial: Migrate sunsu to use has_sysrq

2019-12-18T14:05:06+00:00

The SUPPORT_SYSRQ ifdeffery is not nice as:
- May create misunderstanding about sizeof(struct uart_port) between
  different objects
- Prevents moving functions from serial_core.h
- Reduces readability (well, it's ifdeffery - it's hard to follow)

In order to remove SUPPORT_SYSRQ, has_sysrq variable has been added.
Initialise it in driver's probe and remove ifdeffery.

Cc: "David S. Miller" 
Cc: sparclinux@vger.kernel.org
Signed-off-by: Dmitry Safonov 
Link: https://lore.kernel.org/r/20191213000657.931618-48-dima@arista.com
Signed-off-by: Greg Kroah-Hartman

Merge tag 'tty-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2018-12-29T04:33:54+00:00

Pull tty/serial driver updates from Greg KH:
 "Here is the large TTY/Serial driver set of patches for 4.21-rc1.

  A number of small serial driver changes along with some good tty core
  fixes for long-reported issues with locking. There is also a new
  console font added to the tree, for high-res screens, so that should
  be helpful for many.

  The last patch in the series is a revert of an older one in the tree,
  it came late but it resolves a reported issue that linux-next was
  having for some people.

  Full details are in the shortlog, and all of these, with the exception
  of the revert, have been in linux-next for a while with no reported
  issues"

* tag 'tty-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (85 commits)
  Revert "serial: 8250: Default SERIAL_OF_PLATFORM to SERIAL_8250"
  serial: sccnxp: Allow to use non-standard baud rates
  serial: sccnxp: Adds a delay between sequential read/write cycles
  tty: serial: qcom_geni_serial: Fix UART hang
  tty: serial: qcom_geni_serial: Fix wrap around of TX buffer
  serial: max310x: Fix tx_empty() callback
  dt-bindings: serial: sh-sci: Document r8a774c0 bindings
  dt-bindings: serial: sh-sci: Document r8a774a1 bindings
  Fonts: New Terminus large console font
  dt-bindings: serial: lpuart: add imx8qxp compatible string
  serial: uartps: Fix interrupt mask issue to handle the RX interrupts properly
  serial: uartps: Fix error path when alloc failed
  serial: uartps: Check if the device is a console
  serial: uartps: Add the device_init_wakeup
  tty: serial: samsung: Increase maximum baudrate
  tty: serial: samsung: Properly set flags in autoCTS mode
  tty: Use of_node_name_{eq,prefix} for node name comparisons
  tty/serial: do not free trasnmit buffer page under port lock
  serial: 8250: Rate limit serial port rx interrupts during input overruns
  dt-bindings: serial: 8250: Add rate limit for serial port input overruns
  ...

serial/sunsu: fix refcount leak

2018-12-21T19:24:38+00:00

The function of_find_node_by_path() acquires a reference to the node
returned by it and that reference needs to be dropped by its caller.

su_get_type() doesn't do that. The match node are used as an identifier
to compare against the current node, so we can directly drop the refcount
after getting the node from the path as it is not used as pointer.

Fix this by use a single variable and drop the refcount right after
of_find_node_by_path().

Signed-off-by: Yangtao Li 
Signed-off-by: David S. Miller

tty: Use of_node_name_{eq,prefix} for node name comparisons

2018-12-17T15:12:17+00:00

Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.

For hvc, the code can also be simplified by using of_stdout pointer
instead of searching again for the stdout node.

Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Greg Kroah-Hartman 
Cc: Jiri Slaby 
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-serial@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Signed-off-by: Rob Herring 
Acked-by: Michael Ellerman 
Acked-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman