Sealevel XR17V35X based devices are inoperable on kernel versions
4.11 and above due to a change in the GPIO preconfiguration introduced in
commit
7dea8165f1. This patch fixes this by preconfiguring the GPIO on Sealevel
cards to the value (0x00) used prior to commit 7dea8165f1
With GPIOs preconfigured as per commit 7dea8165f1 all ports on
Sealevel XR17V35X based devices become stuck in high impedance
mode, regardless of dip-switch or software configuration. This
causes the device to become effectively unusable. This patch (in
various forms) has been distributed to our customers and no issues
related to it have been reported.
Fixes: 7dea8165f1 ("serial: exar: Preconfigure xr17v35x MPIOs as output")
Signed-off-by: Matthew Howell <matthew.howell@sealevel.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2007221605270.13247@tstest-VirtualBox
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 7b668c064e ("serial: 8250: Fix max baud limit in generic 8250
port") fixed limits of a baud rate setting for a generic 8250 port.
In other words since that commit the baud rate has been permitted to be
within [uartclk / 16 / UART_DIV_MAX; uartclk / 16], which is absolutely
normal for a standard 8250 UART port. But there are custom 8250 ports,
which provide extended baud rate limits. In particular the Mediatek 8250
port can work with baud rates up to "uartclk" speed.
Normally that and any other peculiarity is supposed to be handled in a
custom set_termios() callback implemented in the vendor-specific
8250-port glue-driver. Currently that is how it's done for the most of
the vendor-specific 8250 ports, but for some reason for Mediatek a
solution has been spread out to both the glue-driver and to the generic
8250-port code. Due to that a bug has been introduced, which permitted the
extended baud rate limit for all even for standard 8250-ports. The bug
has been fixed by the commit 7b668c064e ("serial: 8250: Fix max baud
limit in generic 8250 port") by narrowing the baud rates limit back down to
the normal bounds. Unfortunately by doing so we also broke the
Mediatek-specific extended bauds feature.
A fix of the problem described above is twofold. First since we can't get
back the extended baud rate limits feature to the generic set_termios()
function and that method supports only a standard baud rates range, the
requested baud rate must be locally stored before calling it and then
restored back to the new termios structure after the generic set_termios()
finished its magic business. By doing so we still use the
serial8250_do_set_termios() method to set the LCR/MCR/FCR/etc. registers,
while the extended baud rate setting procedure will be performed later in
the custom Mediatek-specific set_termios() callback. Second since a true
baud rate is now fully calculated in the custom set_termios() method we
need to locally update the port timeout by calling the
uart_update_timeout() function. After the fixes described above are
implemented in the 8250_mtk.c driver, the Mediatek 8250-port should
get back to normally working with extended baud rates.
Link: https://lore.kernel.org/linux-serial/20200701211337.3027448-1-danielwinkler@google.com
Fixes: 7b668c064e ("serial: 8250: Fix max baud limit in generic 8250 port")
Reported-by: Daniel Winkler <danielwinkler@google.com>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: stable <stable@vger.kernel.org>
Tested-by: Claire Chang <tientzu@chromium.org>
Link: https://lore.kernel.org/r/20200714124113.20918-1-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The struct tty_port is part of the uart state and will never be NULL in
the receive helpers. Drop the bogus NULL checks and rename the
pointer-variables "port" to differentiate them from struct tty_struct
pointers (which can be NULL).
Fixes: 962963e4ee ("serial: tegra: Switch to using struct tty_port")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200710135947.2737-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 33ae787b74 ("serial: tegra: add support to ignore read") added
support for dropping input in case CREAD isn't set, but for PIO the
ignore_status_mask wasn't checked until after the character had been
put in the receive buffer.
Note that the NULL tty-port test is bogus and will be removed by a
follow-on patch.
Fixes: 33ae787b74 ("serial: tegra: add support to ignore read")
Cc: stable <stable@vger.kernel.org> # 5.4
Cc: Shardar Shariff Md <smohammed@nvidia.com>
Cc: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200710135947.2737-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The problems started with the revert (18cc7ac8a2). The
cdns_uart_console.index is statically assigned -1. When the port is
registered, Linux assigns consecutive numbers to it. It turned out that
when using ttyPS1 as console, the index is not updated as we are reusing
the same cdns_uart_console instance for multiple ports. When registering
ttyPS0, it gets updated from -1 to 0, but when registering ttyPS1, it
already is 0 and not updated.
That led to 2ae11c46d5. It assigns the index prior to registering
the uart_driver once. Unfortunately, that ended up breaking the
situation where the probe order does not match the id order. When using
the same device tree for both uboot and linux, it is important that the
serial0 alias points to the console. So some boards reverse those
aliases. This was reported by Jan Kiszka. The proposed fix was reverting
the index assignment and going back to the previous iteration.
However such a reversed assignement (serial0 -> uart1, serial1 -> uart0)
was already partially broken by the revert (18cc7ac8a2). While the
ttyPS device works, the kmsg connection is already broken and kernel
messages go missing. Reverting the id assignment does not fix this.
>From the xilinx_uartps driver pov (after reverting the refactoring
commits), there can be only one console. This manifests in static
variables console_pprt and cdns_uart_console. These variables are not
properly linked and can go out of sync. The cdns_uart_console.index is
important for uart_add_one_port. We call that function for each port -
one of which hopefully is the console. If it isn't, the CON_ENABLED flag
is not set and console_port is cleared. The next cdns_uart_probe call
then tries to register the next port using that same cdns_uart_console.
It is important that console_port and cdns_uart_console (and its index
in particular) stay in sync. The index assignment implemented by
Shubhrajyoti Datta is correct in principle. It just may have to happen a
second time if the first cdns_uart_probe call didn't encounter the
console device. And we shouldn't change the index once the console uart
is registered.
Reported-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Reported-by: Jan Kiszka <jan.kiszka@web.de>
Link: https://lore.kernel.org/linux-serial/f4092727-d8f5-5f91-2c9f-76643aace993@siemens.com/
Fixes: 18cc7ac8a2 ("Revert "serial: uartps: Register own uart console and driver structures"")
Fixes: 2ae11c46d5 ("tty: xilinx_uartps: Fix missing id assignment to the console")
Fixes: 76ed2e1057 ("Revert "tty: xilinx_uartps: Fix missing id assignment to the console"")
Signed-off-by: Helmut Grohne <helmut.grohne@intenta.de>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200713073227.GA3805@laureti-dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are some small tty and serial driver fixes for 5.8-rc6.
The largest set of patches in here is a revert of the sysrq changes that
went into 5.8-rc1 but turned out to cause a noticable overhead and cpu
usage.
Other than that, there's a few small serial driver fixes to resolve
reported issues, and finally resolving the spinlock init problem on many
serial driver consoles.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty into master
Pull tty/serial driver fixes from Greg KH:
:Here are some small tty and serial driver fixes for 5.8-rc6.
The largest set of patches in here is a revert of the sysrq changes
that went into 5.8-rc1 but turned out to cause a noticable overhead
and cpu usage.
Other than that, there's a few small serial driver fixes to resolve
reported issues, and finally resolving the spinlock init problem on
many serial driver consoles.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: core: Initialise spin lock before use in uart_configure_port()
serial: mxs-auart: add missed iounmap() in probe failure and remove
serial: sh-sci: Initialize spinlock for uart console
Revert "tty: xilinx_uartps: Fix missing id assignment to the console"
serial: core: drop redundant sysrq checks
serial: core: fix sysrq overhead regression
Revert "serial: core: Refactor uart_unlock_and_check_sysrq()"
tty/serial: fix serial_core.c kernel-doc warnings
tty: serial: cpm_uart: Fix behaviour for non existing GPIOs
The comment near to uart_port_spin_lock_init() says:
Ensure that the serial console lock is initialised early.
If this port is a console, then the spinlock is already initialised.
and there is nothing about enabled or disabled consoles. The commit
a3cb39d258 ("serial: core: Allow detach and attach serial device
for console") made a change, which follows the comment, and also to
prevent reinitialisation of the lock in use, when user detaches and
attaches back the same console device. But this change discovers
another issue, that uart_add_one_port() tries to access a spin lock
that now may be uninitialised. This happens when a driver expects
the serial core to register a console on its behalf. In this case
we must initialise a spin lock before use.
Fixes: a3cb39d258 ("serial: core: Allow detach and attach serial device for console")
Reported-by: Marc Zyngier <maz@kernel.org>
Reported-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Anatoly Pugachev <matorola@gmail.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20200706214903.56148-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This driver calls ioremap() in probe, but it misses calling iounmap() in
probe's error handler and remove.
Add the missed calls to fix it.
Fixes: 47d37d6f94 ("serial: Add auart driver for i.MX23/28")
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200709135608.68290-1-hslester96@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 2ae11c46d5.
It turned out to break the ultra96-rev1, e.g., which uses uart1 as
serial0 (and stdout-path = "serial0:115200n8").
Fixes: 2ae11c46d5 ("tty: xilinx_uartps: Fix missing id assignment to the console")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/f4092727-d8f5-5f91-2c9f-76643aace993@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 8e20fc3917 ("serial_core: Move sysrq functions from header
file") converted the inline sysrq helpers to exported functions which
are now called for every received character, interrupt and break signal
also on systems without CONFIG_MAGIC_SYSRQ_SERIAL instead of being
optimised away by the compiler.
Inlining these helpers again also avoids the function call overhead when
CONFIG_MAGIC_SYSRQ_SERIAL is enabled (e.g. when the port is not used as
a console).
Fixes: 8e20fc3917 ("serial_core: Move sysrq functions from header file")
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://lore.kernel.org/r/20200610152232.16925-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit da9a5aa340.
In order to ease backporting a fix for a sysrq regression, revert this
rewrite which was since added on top.
The other sysrq helpers now bail out early when sysrq is not enabled;
it's better to keep that pattern here as well.
Note that the __releases() attribute won't be needed after the follow-on
fix either.
Fixes: da9a5aa340 ("serial: core: Refactor uart_unlock_and_check_sysrq()")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200610152232.16925-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
devm_gpiod_get_index() doesn't return NULL but -ENOENT when the
requested GPIO doesn't exist, leading to the following messages:
[ 2.742468] gpiod_direction_input: invalid GPIO (errorpointer)
[ 2.748147] can't set direction for gpio #2: -2
[ 2.753081] gpiod_direction_input: invalid GPIO (errorpointer)
[ 2.758724] can't set direction for gpio #3: -2
[ 2.763666] gpiod_direction_output: invalid GPIO (errorpointer)
[ 2.769394] can't set direction for gpio #4: -2
[ 2.774341] gpiod_direction_input: invalid GPIO (errorpointer)
[ 2.779981] can't set direction for gpio #5: -2
[ 2.784545] ff000a20.serial: ttyCPM1 at MMIO 0xfff00a20 (irq = 39, base_baud = 8250000) is a CPM UART
Use devm_gpiod_get_index_optional() instead.
At the same time, handle the error case and properly exit
with an error.
Fixes: 97cbaf2c82 ("tty: serial: cpm_uart: Convert to use GPIO descriptors")
Cc: stable@vger.kernel.org
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/694a25fdce548c5ee8b060ef6a4b02746b8f25c0.1591986307.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In kgdb context, calling console handlers aren't safe due to locks used
in those handlers which could in turn lead to a deadlock. Although, using
oops_in_progress increases the chance to bypass locks in most console
handlers but it might not be sufficient enough in case a console uses
more locks (VT/TTY is good example).
Currently when a driver provides both polling I/O and a console then kdb
will output using the console. We can increase robustness by using the
currently active polling I/O driver (which should be lockless) instead
of the corresponding console. For several common cases (e.g. an
embedded system with a single serial port that is used both for console
output and debugger I/O) this will result in no console handler being
used.
In order to achieve this we need to reverse the order of preference to
use dbg_io_ops (uses polling I/O mode) over console APIs. So we just
store "struct console" that represents debugger I/O in dbg_io_ops and
while emitting kdb messages, skip console that matches dbg_io_ops
console in order to avoid duplicate messages. After this change,
"is_console" param becomes redundant and hence removed.
Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/1591264879-25920-5-git-send-email-sumit.garg@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.
This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.
There are a variety of indentation styles found.
a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'
In order to convert all of them to 1 tab + 'help', I ran the
following commend:
$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Here is the tty and serial driver updates for 5.8-rc1
Nothing huge at all, just a lot of little serial driver fixes, updates
for new devices and features, and other small things. Full details are
in the shortlog.
Note, you will get a conflict merging with your tree in the
Documentation/devicetree/bindings/serial/rs485.yaml file, but it should
be pretty obvious what to do. If not, I'm sure Rob will clean it all up
afterwards :)
All of these have been in linux-next with no issues for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here is the tty and serial driver updates for 5.8-rc1
Nothing huge at all, just a lot of little serial driver fixes, updates
for new devices and features, and other small things. Full details are
in the shortlog.
All of these have been in linux-next with no issues for a while"
* tag 'tty-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (67 commits)
tty: serial: qcom_geni_serial: Add 51.2MHz frequency support
tty: serial: imx: clear Ageing Timer Interrupt in handler
serial: 8250_fintek: Add F81966 Support
sc16is7xx: Add flag to activate IrDA mode
dt-bindings: sc16is7xx: Add flag to activate IrDA mode
serial: 8250: Support rs485 bus termination GPIO
serial: 8520_port: Fix function param documentation
dt-bindings: serial: Add binding for rs485 bus termination GPIO
vt: keyboard: avoid signed integer overflow in k_ascii
serial: 8250: Enable 16550A variants by default on non-x86
tty: hvc_console, fix crashes on parallel open/close
serial: imx: Initialize lock for non-registered console
sc16is7xx: Read the LSR register for basic device presence check
sc16is7xx: Allow sharing the IRQ line
sc16is7xx: Use threaded IRQ
sc16is7xx: Always use falling edge IRQ
tty: n_gsm: Fix bogus i++ in gsm_data_kick
tty: n_gsm: Remove unnecessary test in gsm_print_packet()
serial: stm32: add no_console_suspend support
tty: serial: fsl_lpuart: Use __maybe_unused instead of #if CONFIG_PM_SLEEP
...
By far the biggest change in this cycle are the changes that allow much
earlier debug of systems that are hooked up via UART by taking advantage
of the earlycon framework to implement the kgdb I/O hooks before handing
over to the regular polling I/O drivers once they are available. When
discussing Doug's work we also found and fixed an broken
raw_smp_processor_id() sequence in in_dbg_master().
Also included are a collection of much smaller fixes and tweaks: a
couple of tweaks to ged rid of doc gen or coccicheck warnings, future
proof some internal calculations that made implicit power-of-2
assumptions and eliminate some rather weird handling of magic
environment variables in kdb.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
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Merge tag 'kgdb-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux
Pull kgdb updates from Daniel Thompson:
"By far the biggest change in this cycle are the changes that allow
much earlier debug of systems that are hooked up via UART by taking
advantage of the earlycon framework to implement the kgdb I/O hooks
before handing over to the regular polling I/O drivers once they are
available. When discussing Doug's work we also found and fixed an
broken raw_smp_processor_id() sequence in in_dbg_master().
Also included are a collection of much smaller fixes and tweaks: a
couple of tweaks to ged rid of doc gen or coccicheck warnings, future
proof some internal calculations that made implicit power-of-2
assumptions and eliminate some rather weird handling of magic
environment variables in kdb"
* tag 'kgdb-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
kdb: Remove the misfeature 'KDBFLAGS'
kdb: Cleanup math with KDB_CMD_HISTORY_COUNT
serial: amba-pl011: Support kgdboc_earlycon
serial: 8250_early: Support kgdboc_earlycon
serial: qcom_geni_serial: Support kgdboc_earlycon
serial: kgdboc: Allow earlycon initialization to be deferred
Documentation: kgdboc: Document new kgdboc_earlycon parameter
kgdb: Don't call the deinit under spinlock
kgdboc: Disable all the early code when kgdboc is a module
kgdboc: Add kgdboc_earlycon to support early kgdb using boot consoles
kgdboc: Remove useless #ifdef CONFIG_KGDB_SERIAL_CONSOLE in kgdboc
kgdb: Prevent infinite recursive entries to the debugger
kgdb: Delay "kgdbwait" to dbg_late_init() by default
kgdboc: Use a platform device to handle tty drivers showing up late
Revert "kgdboc: disable the console lock when in kgdb"
kgdb: Disable WARN_CONSOLE_UNLOCKED for all kgdb
kgdb: Return true in kgdb_nmi_poll_knock()
kgdb: Drop malformed kernel doc comment
kgdb: Fix spurious true from in_dbg_master()
Implement the read() function in the early console driver. With
recently added kgdboc_earlycon feature, this allows you to use kgdb
to debug fairly early into the system boot.
We only bother implementing this if polling is enabled since kgdb can't
be enabled without that.
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200507130644.v4.12.I8ee0811f0e0816dd8bfe7f2f5540b3dba074fae8@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Implement the read() function in the early console driver. With
recent kgdb patches this allows you to use kgdb to debug fairly early
into the system boot.
We only bother implementing this if polling is enabled since kgdb
can't be enabled without that.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20200507130644.v4.11.I8f668556c244776523320a95b09373a86eda11b7@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Implement the read() function in the early console driver. With
recent kgdb patches this allows you to use kgdb to debug fairly early
into the system boot.
We only bother implementing this if polling is enabled since kgdb
can't be enabled without that.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200507130644.v4.10.If2deff9679a62c1ce1b8f2558a8635dc837adf8c@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Currently there is no guarantee that an earlycon will be initialized
before kgdboc tries to adopt it. Almost the opposite: on systems
with ACPI then if earlycon has no arguments then it is guaranteed that
earlycon will not be initialized.
This patch mitigates the problem by giving kgdboc_earlycon a second
chance during console_init(). This isn't quite as good as stopping during
early parameter parsing but it is still early in the kernel boot.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20200430161741.1832050-1-daniel.thompson@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
When kgdboc is compiled as a module all of the "ekgdboc" and
"kgdb_earlycon" code isn't useful and, in fact, breaks compilation.
This is because early_param() isn't defined for modules and that's how
this code gets configured.
It turns out that this was broken by commit eae3e19ca9 ("kgdboc:
Remove useless #ifdef CONFIG_KGDB_SERIAL_CONSOLE in kgdboc") and then
made worse by commit 220995622d ("kgdboc: Add kgdboc_earlycon to
support early kgdb using boot consoles"). I guess the #ifdef wasn't
so useless, even if it wasn't obvious why it was useful. When kgdboc
was compiled as a module only "CONFIG_KGDB_SERIAL_CONSOLE_MODULE" was
defined, not "CONFIG_KGDB_SERIAL_CONSOLE". That meant that the old
module.
Let's basically do the same thing that the old code (pre-removal of
the #ifdef) did but use "IS_BUILTIN(CONFIG_KGDB_SERIAL_CONSOLE)" to
make it more obvious what the point of the check is. We'll fix
kgdboc_earlycon in a similar way.
Fixes: 220995622d ("kgdboc: Add kgdboc_earlycon to support early kgdb using boot consoles")
Fixes: eae3e19ca9 ("kgdboc: Remove useless #ifdef CONFIG_KGDB_SERIAL_CONSOLE in kgdboc")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200519084345.1.I91670accc8a5ddabab227eb63bb4ad3e2e9d2b58@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
To support BT use case over UART at baud rate of 3.2 Mbps,
we need SE clocks to run at 51.2MHz frequency. Previously this
frequency was not available in clk src, so, we were requesting
for 102.4 MHz and dividing it internally by 2 to get 51.2MHz.
As now 51.2MHz frequency is made available in clk src,
adding this frequency to UART frequency table.
We will save significant amount of power, if 51.2 is used
because it belongs to LowSVS range whereas 102.4 fall into
Nominal category.
Signed-off-by: satya priya <skakit@codeaurora.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/1590747282-5487-1-git-send-email-skakit@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The AGTIM flag must be cleared explicitly, otherwise the IRQ handler
will be called in an endless loop.
Fortunately, this issue currently doesn't affect mainline kernels in
practice, as the the RX FIFO trigger level is set to 1 in UFCR. When
setting the trigger level to a higher number, the issue is trivially
reproducible by any RX without DMA that doesn't fill the FIFO up to the
configured level.
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Link: https://lore.kernel.org/r/20200528154747.14201-1-matthias.schiffer@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fintek F81966 is a LPC/eSPI to 6 UARTs SuperIO. It has fully compatible
with F81866. It's also need check the IRQ mode with system assigned.
F81966 IRQ Mode setting:
0xf0
Bit1: IRQ_MODE0
Bit0: Share mode (always on)
0xf6
Bit3: IRQ_MODE1
Level/Low: IRQ_MODE0:0, IRQ_MODE1:0
Edge/High: IRQ_MODE0:1, IRQ_MODE1:0
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Cc: Ji-Ze Hong (Peter Hong) <peter_hong@fintek.com.tw>
Link: https://lore.kernel.org/r/20200528022429.32078-1-hpeter+linux_kernel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This series of uart controllers is able to work in IrDA mode.
Add per-port flag to the device-tree to enable that feature if needed.
Signed-off-by: Pascal Huerst <pascal.huerst@gmail.com>
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200529055058.1606910-3-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit e8759ad17d ("serial: uapi: Add support for bus termination")
introduced the ability to enable rs485 bus termination from user space.
So far the feature is only used by a single driver, 8250_exar.c, using a
hardcoded GPIO pin specific to Siemens IOT2040 products.
Provide for a more generic solution by allowing specification of an
rs485 bus termination GPIO pin in the device tree: Amend the serial
core to retrieve the GPIO from the device tree (or ACPI table) and amend
the default ->rs485_config() callback for 8250 drivers to change the
GPIO on request from user space.
Perhaps 8250_exar.c can be converted to the generic approach in a
follow-up patch.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Link: https://lore.kernel.org/r/94c6c800d1ca9fa04766dd1d43a8272c5ad4bedd.1589811297.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The parameter is named p while the documentation talks about up.
Fix the doc to be in line with the code.
Fixes: 058bc104f7 ("serial: 8250: Generalize rs485 software emulation")
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200517215610.2131618-2-heiko@sntech.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some embedded devices still use these serial ports; make sure they're
still enabled by default on architectures more likely to have them, to
avoid rendering someone's console unavailable.
Reported-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reported-by: Maxim Kochetkov <fido_max@inbox.ru>
Fixes: dc56ecb81a ("serial: 8250: Support disabling mdelay-filled probes of 16550A variants")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Link: https://lore.kernel.org/r/a20b5fb7dd295cfb48160eecf4bdebd76332d67d.1590509426.git.josh@joshtriplett.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit a3cb39d258
("serial: core: Allow detach and attach serial device for console")
changed a bit logic behind lock initialization since for most of the console
driver it's supposed to have lock already initialized even if console is not
enabled. However, it's not the case for Freescale IMX console.
Initialize lock explicitly in the ->probe().
Note, there is still an open question should or shouldn't not this driver
register console properly.
Fixes: a3cb39d258 ("serial: core: Allow detach and attach serial device for console")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200525105952.13744-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the driver probes just fine and binds all its resources even
if the physical device is not present.
As the device lacks an identification register, let's at least read the
LSR register to check whether a device at the configured address responds
to the request at all.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-7-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the interrupt line is shared with other devices, the IRQ must be
level-triggered, as only one device can trigger a falling edge. To support
this, try to acquire the IRQ with IRQF_TRIGGER_LOW|IRQF_SHARED first.
Interrupt controllers that lack support for level-triggers will return an
error, in which case the driver will now retry the acqusition with
IRQF_TRIGGER_FALLING, which was also the default before.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-6-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use a threaded IRQ handler to get rid of the irq_work kthread.
This also allows for the driver to use interrupts generated by
a threaded controller.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-5-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver currently only uses IRQF_TRIGGER_FALLING if the probing
happened without a device-tree setup. The device however will always
generate falling edges on its IRQ line, so let's use that flag in
all cases.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-4-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In order to display console messages in low power mode, console pins
must be kept active after suspend call.
Initial patch "serial: stm32: add support for no_console_suspend" was part
of "STM32 usart power improvement" series, but as dependancy to
console_suspend pinctl state has been removed to fit with Rob comment [1],
this patch has no more dependancy with any other patch of this series.
[1] https://lkml.org/lkml/2019/7/9/451
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>
Link: https://lore.kernel.org/r/20200519094104.27082-1-erwan.leray@st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We want to enable kgdb to debug the early parts of the kernel.
Unfortunately kgdb normally is a client of the tty API in the kernel
and serial drivers don't register to the tty layer until fairly late
in the boot process.
Serial drivers do, however, commonly register a boot console. Let's
enable the kgdboc driver to work with boot consoles to provide early
debugging.
This change co-opts the existing read() function pointer that's part
of "struct console". It's assumed that if a boot console (with the
flag CON_BOOT) has implemented read() that both the read() and write()
function are polling functions. That means they work without
interrupts and read() will return immediately (with 0 bytes read) if
there's nothing to read. This should be a safe assumption since it
appears that no current boot consoles implement read() right now and
there seems no reason to do so unless they wanted to support
"kgdboc_earlycon".
The normal/expected way to make all this work is to use
"kgdboc_earlycon" and "kgdboc" together. You should point them both
to the same physical serial connection. At boot time, as the system
transitions from the boot console to the normal console (and registers
a tty), kgdb will switch over.
One awkward part of all this, though, is that there can be a window
where the boot console goes away and we can't quite transtion over to
the main kgdboc that uses the tty layer. There are two main problems:
1. The act of registering the tty doesn't cause any call into kgdboc
so there is a window of time when the tty is there but kgdboc's
init code hasn't been called so we can't transition to it.
2. On some serial drivers the normal console inits (and replaces the
boot console) quite early in the system. Presumably these drivers
were coded up before earlycon worked as well as it does today and
probably they don't need to do this anymore, but it causes us
problems nontheless.
Problem #1 is not too big of a deal somewhat due to the luck of probe
ordering. kgdboc is last in the tty/serial/Makefile so its probe gets
right after all other tty devices. It's not fun to rely on this, but
it does work for the most part.
Problem #2 is a big deal, but only for some serial drivers. Other
serial drivers end up registering the console (which gets rid of the
boot console) and tty at nearly the same time.
The way we'll deal with the window when the system has stopped using
the boot console and the time when we're setup using the tty is to
keep using the boot console. This may sound surprising, but it has
been found to work well in practice. If it doesn't work, it shouldn't
be too hard for a given serial driver to make it keep working.
Specifically, it's expected that the read()/write() function provided
in the boot console should be the same (or nearly the same) as the
normal kgdb polling functions. That means continuing to use them
should work just fine. To make things even more likely to work work
we'll also trap the recently added exit() function in the boot console
we're using and delay any calls to it until we're all done with the
boot console.
NOTE: there could be ways to use all this in weird / unexpected ways.
If you do something like this, it's a bit of a buyer beware situation.
Specifically:
- If you specify only "kgdboc_earlycon" but not "kgdboc" then
(depending on your serial driver) things will probably work OK, but
you'll get a warning printed the first time you use kgdb after the
boot console is gone. You'd only be able to do this, of course, if
the serial driver you're running atop provided an early boot console.
- If your "kgdboc_earlycon" and "kgdboc" devices are not the same
device things should work OK, but it'll be your job to switch over
which device you're monitoring (including figuring out how to switch
over gdb in-flight if you're using it).
When trying to enable "kgdboc_earlycon" it should be noted that the
names that are registered through the boot console layer and the tty
layer are not the same for the same port. For example when debugging
on one board I'd need to pass "kgdboc_earlycon=qcom_geni
kgdboc=ttyMSM0" to enable things properly. Since digging up the boot
console name is a pain and there will rarely be more than one boot
console enabled, you can provide the "kgdboc_earlycon" parameter
without specifying the name of the boot console. In this case we'll
just pick the first boot that implements read() that we find.
This new "kgdboc_earlycon" parameter should be contrasted to the
existing "ekgdboc" parameter. While both provide a way to debug very
early, the usage and mechanisms are quite different. Specifically
"kgdboc_earlycon" is meant to be used in tandem with "kgdboc" and
there is a transition from one to the other. The "ekgdboc" parameter,
on the other hand, replaces the "kgdboc" parameter. It runs the same
logic as the "kgdboc" parameter but just relies on your TTY driver
being present super early. The only known usage of the old "ekgdboc"
parameter is documented as "ekgdboc=kbd earlyprintk=vga". It should
be noted that "kbd" has special treatment allowing it to init early as
a tty device.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/20200507130644.v4.8.I8fba5961bf452ab92350654aa61957f23ecf0100@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
This file is only ever compiled if that config is on since the
Makefile says:
obj-$(CONFIG_KGDB_SERIAL_CONSOLE) += kgdboc.o
Let's get rid of the useless #ifdef.
Reported-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200507130644.v4.7.Icb528f03d0026d957e60f537aa711ada6fd219dc@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
If you build CONFIG_KGDB_SERIAL_CONSOLE into the kernel then you
should be able to have KGDB init itself at bootup by specifying the
"kgdboc=..." kernel command line parameter. This has worked OK for me
for many years, but on a new device I switched to it stopped working.
The problem is that on this new device the serial driver gets its
probe deferred. Now when kgdb initializes it can't find the tty
driver and when it gives up it never tries again.
We could try to find ways to move up the initialization of the serial
driver and such a thing might be worthwhile, but it's nice to be
robust against serial drivers that load late. We could move kgdb to
init itself later but that penalizes our ability to debug early boot
code on systems where the driver inits early. We could roll our own
system of detecting when new tty drivers get loaded and then use that
to figure out when kgdb can init, but that's ugly.
Instead, let's jump on the -EPROBE_DEFER bandwagon. We'll create a
singleton instance of a "kgdboc" platform device. If we can't find
our tty device when the singleton "kgdboc" probes we'll return
-EPROBE_DEFER which means that the system will call us back later to
try again when the tty device might be there.
We won't fully transition all of the kgdboc to a platform device
because early kgdb initialization (via the "ekgdboc" kernel command
line parameter) still runs before the platform device has been
created. The kgdb platform device is merely used as a convenient way
to hook into the system's normal probe deferral mechanisms.
As part of this, we'll ever-so-slightly change how the "kgdboc=..."
kernel command line parameter works. Previously if you booted up and
kgdb couldn't find the tty driver then later reading
'/sys/module/kgdboc/parameters/kgdboc' would return a blank string.
Now kgdb will keep track of the string that came as part of the
command line and give it back to you. It's expected that this should
be an OK change.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20200507130644.v4.3.I4a493cfb0f9f740ce8fd2ab58e62dc92d18fed30@changeid
[daniel.thompson@linaro.org: Make config_mutex static]
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
This reverts commit 81eaadcae8.
Commit 81eaadcae8 ("kgdboc: disable the console lock when in kgdb")
is no longer needed now that we have the patch ("kgdb: Disable
WARN_CONSOLE_UNLOCKED for all kgdb"). Revert it.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20200507130644.v4.2.I02258eee1497e55bcbe8dc477de90369c7c7c2c5@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
An uninitialised spin lock for sifive serial console raises a bad
magic spin_lock error as reported and discussed here [1].
Initialising the spin lock resolves the issue.
The fix is tested on HiFive Unleashed A00 board with Linux 5.7-rc4
and OpenSBI v0.7
[1] https://lore.kernel.org/linux-riscv/b9fe49483a903f404e7acc15a6efbef756db28ae.camel@wdc.com
Fixes: 45c054d081 ("tty: serial: add driver for the SiFive UART")
Reported-by: Atish Patra <Atish.Patra@wdc.com>
Signed-off-by: Sagar Shrikant Kadam <sagar.kadam@sifive.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1589019852-21505-2-git-send-email-sagar.kadam@sifive.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Standard 8250 UART ports are designed in a way so they can communicate
with baud rates up to 1/16 of a reference frequency. It's expected from
most of the currently supported UART controllers. That's why the former
version of serial8250_get_baud_rate() method called uart_get_baud_rate()
with min and max baud rates passed as (port->uartclk / 16 / UART_DIV_MAX)
and ((port->uartclk + tolerance) / 16) respectively. Doing otherwise, like
it was suggested in commit ("serial: 8250_mtk: support big baud rate."),
caused acceptance of bauds, which was higher than the normal UART
controllers actually supported. As a result if some user-space program
requested to set a baud greater than (uartclk / 16) it would have been
permitted without truncation, but then serial8250_get_divisor(baud)
(which calls uart_get_divisor() to get the reference clock divisor) would
have returned a zero divisor. Setting zero divisor will cause an
unpredictable effect varying from chip to chip. In case of DW APB UART the
communications just stop.
Lets fix this problem by getting back the limitation of (uartclk +
tolerance) / 16 maximum baud supported by the generic 8250 port. Mediatek
8250 UART ports driver developer shouldn't have touched it in the first
place notably seeing he already provided a custom version of set_termios()
callback in that glue-driver which took into account the extended baud
rate values and accordingly updated the standard and vendor-specific
divisor latch registers anyway.
Fixes: 81bb549fdf ("serial: 8250_mtk: support big baud rate.")
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Long Cheng <long.cheng@mediatek.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: linux-mips@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mediatek@lists.infradead.org
Link: https://lore.kernel.org/r/20200506233136.11842-2-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We're about to amend uart_get_rs485_mode() to support a GPIO pin for
rs485 bus termination. Retrieving the GPIO descriptor may fail, so
allow uart_get_rs485_mode() to return an errno and change all callers
to check for failure.
The GPIO descriptor is going to be stored in struct uart_port. Pass
that struct to uart_get_rs485_mode() in lieu of a struct device and
struct serial_rs485, both of which are directly accessible from struct
uart_port.
A few drivers call uart_get_rs485_mode() before setting the struct
device pointer in struct uart_port. Shuffle those calls around where
necessary.
[Heiko Stuebner did the ar933x_uart.c portion, hence his Signed-off-by.]
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/271e814af4b0db3bffbbb74abf2b46b75add4516.1589285873.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the call to uart_add_one_port() in serial8250_register_8250_port()
fails, a half-initialized entry in the serial_8250ports[] array is left
behind.
A subsequent reprobe of the same serial port causes that entry to be
reused. Because uart->port.dev is set, uart_remove_one_port() is called
for the half-initialized entry and bails out with an error message:
bcm2835-aux-uart 3f215040.serial: Removing wrong port: (null) != (ptrval)
The same happens on failure of mctrl_gpio_init() since commit
4a96895f74 ("tty/serial/8250: use mctrl_gpio helpers").
Fix by zeroing the uart->port.dev pointer in the probe error path.
The bug was introduced in v2.6.10 by historical commit befff6f5bf5f
("[SERIAL] Add new port registration/unregistration functions."):
https://git.kernel.org/tglx/history/c/befff6f5bf5f
The commit added an unconditional call to uart_remove_one_port() in
serial8250_register_port(). In v3.7, commit 835d844d1a ("8250_pnp:
do pnp probe before legacy probe") made that call conditional on
uart->port.dev which allows me to fix the issue by zeroing that pointer
in the error path. Thus, the present commit will fix the problem as far
back as v3.7 whereas still older versions need to also cherry-pick
835d844d1a.
Fixes: 835d844d1a ("8250_pnp: do pnp probe before legacy probe")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v2.6.10
Cc: stable@vger.kernel.org # v2.6.10: 835d844d1a28: 8250_pnp: do pnp probe before legacy
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/b4a072013ee1a1d13ee06b4325afb19bda57ca1b.1589285873.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since PCI core provides a generic PCI_DEVICE_DATA() macro,
replace contents of EXAR_DEVICE() with former one.
No functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200512140252.67631-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Matthew Howell
Serge Semin
Yang Yingliang
Johan Hovold
Helmut Grohne
Linus Torvalds
Andy Shevchenko
Chuhong Yuan
Lad Prabhakar
Jan Kiszka
Randy Dunlap
Christophe Leroy
Sumit Garg
Masahiro Yamada
Douglas Anderson
Daniel Thompson
satya priya
Matthias Schiffer
Ji-Ze Hong (Peter Hong)
Pascal Huerst
Lukas Wunner
Heiko Stuebner
Josh Triplett
Greg Kroah-Hartman
Daniel Mack
Erwan Le Ray
Anson Huang
Sagar Shrikant Kadam