Now the DT bindings has a property to get the FIFO size for a particular port,
retrieve it and use to setup the FIFO interrupts threshold.
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20210518075833.3736038-3-narmstrong@baylibre.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The variable id being initialized with a value that is never read
and it is being updated later with a new value. The initialization is
redundant and can be removed. Since id is just being used in a for-loop
inside a local scope, move the declaration of id to that scope.
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Addresses-Coverity: ("Unused value")
Link: https://lore.kernel.org/r/20210426101106.9122-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The meson driver has always carried an unnecessary workaround for the
infamous low_latency behaviour of tty_flip_buffer_push(), which had
already been removed by the time the driver was added by commit
ff7693d079 ("ARM: meson: serial: add MesonX SoC on-chip uart driver").
Specifically, since commit a9c3f68f3c ("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.
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210421095509.3024-15-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Enable serial driver to be built as a module. To do so, init the
console support on driver/module load instead of using
console_initcall().
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Link: https://lore.kernel.org/r/20201211005744.12855-1-khilman@baylibre.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are the big set of tty and serial driver updates for 5.6-rc1
Included in here are:
- dummy_con cleanups (touches lots of arch code)
- sysrq logic cleanups (touches lots of serial drivers)
- samsung driver fixes (wasn't really being built)
- conmakeshash move to tty subdir out of scripts
- lots of small tty/serial driver updates
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-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here are the big set of tty and serial driver updates for 5.6-rc1
Included in here are:
- dummy_con cleanups (touches lots of arch code)
- sysrq logic cleanups (touches lots of serial drivers)
- samsung driver fixes (wasn't really being built)
- conmakeshash move to tty subdir out of scripts
- lots of small tty/serial driver updates
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (140 commits)
tty: n_hdlc: Use flexible-array member and struct_size() helper
tty: baudrate: SPARC supports few more baud rates
tty: baudrate: Synchronise baud_table[] and baud_bits[]
tty: serial: meson_uart: Add support for kernel debugger
serial: imx: fix a race condition in receive path
serial: 8250_bcm2835aux: Document struct bcm2835aux_data
serial: 8250_bcm2835aux: Use generic remapping code
serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER
serial: 8250_bcm2835aux: Fix line mismatch on driver unbind
serial_core: Remove unused member in uart_port
vt: Correct comment documenting do_take_over_console()
vt: Delete comment referencing non-existent unbind_con_driver()
arch/xtensa/setup: Drop dummy_con initialization
arch/x86/setup: Drop dummy_con initialization
arch/unicore32/setup: Drop dummy_con initialization
arch/sparc/setup: Drop dummy_con initialization
arch/sh/setup: Drop dummy_con initialization
arch/s390/setup: Drop dummy_con initialization
...
ioremap has provided non-cached semantics by default since the Linux 2.6
days, so remove the additional ioremap_nocache interface.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
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: Kevin Hilman <khilman@baylibre.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-amlogic@lists.infradead.org
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20191213000657.931618-22-dima@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At probe, the uart driver tries to get an id from a device tree alias.
When no alias was specified, the driver would return an error and probing
would fail.
Providing an alias for registering a serial device should not be mandatory.
If the device tree does not specify an alias, provide an id from a reserved
range so that the probing can continue.
Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Loys Ollivier <lollivier@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This simply fixes a typo in the preprocessor macros. No functional
changes intended.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the code there are two separate sections which each describe some of
the bits in the AML_UART_CONTROL register.
Merge these into one section to make the code easier to read.
No functional changes intended.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "clear error" bit in the AML_UART_CONTROL register is defined twice.
Remove the AML_UART_CLR_ERR definition and replace it with
AML_UART_CLEAR_ERR.
AML_UART_CLEAR_ERR was chosen to be kept since the datasheet's
description for this bit is "Clear Error" (so developer's don't have to
translate this to "CLR_ERR").
No functional changes intended.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Devices like DCF77 receivers need the baud-rate to be as low as 50.
I have tested this on a Meson GXL device with uart_A.
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Thomas Rohloff <v10lator@myway.de>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the SPDX tag is in all tty files, that identifies the license
in a specific and legally-defined manner. So the extra GPL text wording
can be removed as it is no longer needed at all.
This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.
No copyright headers or other non-license-description text was removed.
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Joachim Eastwood <manabian@gmail.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Richard Genoud <richard.genoud@gmail.com>
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: Pat Gefre <pfg@sgi.com>
Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>
Cc: Sylvain Lemieux <slemieux.tyco@gmail.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Andy Gross <andy.gross@linaro.org>
Cc: David Brown <david.brown@linaro.org>
Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Timur Tabi <timur@tabi.org>
Cc: Tony Prisk <linux@prisktech.co.nz>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.
Update the drivers/tty files files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.
This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: David Sterba <dsterba@suse.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Eric Anholt <eric@anholt.net>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Joachim Eastwood <manabian@gmail.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Richard Genoud <richard.genoud@gmail.com>
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Cc: "Uwe Kleine-König" <kernel@pengutronix.de>
Cc: Pat Gefre <pfg@sgi.com>
Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>
Cc: Sylvain Lemieux <slemieux.tyco@gmail.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Andy Gross <andy.gross@linaro.org>
Cc: David Brown <david.brown@linaro.org>
Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Timur Tabi <timur@tabi.org>
Cc: Tony Prisk <linux@prisktech.co.nz>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This dirver try to implement the Magic SysRq support[1] for
Amlogic Inc's meson platfo
>From the hardware perspective, the UART IP can't detect the 'BREAK' command
clearly via the status register. Instead, we rely on the combination of
'FRAME_ERR bit && ch == 0', and it works fine.
[1] Documentation/admin-guide/sysrq.rst
Signed-off-by: Yixun Lan <dlan@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These uart_ops structures are only stored in the ops field of a
uart_port structure and this fields is const, so the uart_ops
structures can also be const.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch handle the stable UART bindings but also keeps compatibility
with the legacy non-stable bindings until all boards uses them.
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Helmut Klein <hgkr.klein@gmail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The newly added meson_uart_enable_tx_engine function is only called
from the console setup, not the runtime uart, which has an open-coded
version of the same register access. This produces a harmless warning
when the console code is disabled:
drivers/tty/serial/meson_uart.c:127:13: error: 'meson_uart_enable_tx_engine' defined but not used [-Werror=unused-function]
Let's move the function inside of the #ifdef to avoid the warning.
Fixes: ba50f1df13 ("serial: meson: remove unneeded variable assignment in meson_serial_port_write")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change interrupt description from driver name to tty name
(e.g. ttyAML0). If multiple serial ports are enabled this
allows to determine which interrupt belongs to which port
in /proc/interrupts.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Flag UPF_IOREMAP is used by the 8250 subsystem only, it's not used
by the serial core. Therefore I don't see any benefit in using it
here.
In addition fix the order of calls in meson_uart_release_port.
Unmapping needs to be done first, reversing call order in
meson_uart_request_port.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Member mapsize of struct uart_port is meant to store the resource size.
By using it we can get rid of meson_uart_res_size().
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
val is set in both branches of the if clause, therefore the two
removed lines are dead code.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There's no need to set AML_UART_TX_EN in each call to
meson_serial_port_write. In addition to meson_uart_startup
set this flag in meson_serial_console_setup and
meson_serial_early_console_setup.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The stop bit value as to be or'ed, so far this worked only just by chance
because AML_UART_STOP_BIN_1SB is 0.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The vendor driver allows setting baud-rates higher than 115200 baud.
There is a check in the vendor driver which prevents using more than
115200 baud during startup, however it does not have such a check in
.set_termios.
Higher baud-rates are often used by the bluetooth modules embedded into
the SDIO wifi chips (Amlogic devices use brcmfmac based wifi chips quite
often, 2000000 baud seems to be a common value for the UART baud-rate in
Amlogic's "libbt").
I have tested this on a Meson GXL device with uart_A (to which the
bluetooth module is connected, where initialization times out with
115200 baud) and uart_AO (which I manually set to 2000000 baud and then
connected with my USB UART adapter to that).
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Split off the bulk of the existing meson_serial_console_write()
implementation into meson_serial_port_write() for implementing
meson_serial_early_console_write().
Use "meson" as the earlycon driver name, courtesy of Nicolas.
Signed-off-by: Nicolas Saenz Julienne <nicolassaenzj@gmail.com>
Acked-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix the baudrate calculation for 24 MHz XTAL clock found on gxbb platforms.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Acked-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ensure that if the interrupt handler is entered then only try and do tx
work if the tx irq is enabled.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tx_stop() call turns the interrupt off, but the tx_start() does not
check if the interrupt is enabled. Switch it back on if there is more
work to do.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As an attempt to stop issues with bad console output, ensure that both the
rx and tx interrupts are disabled during the console write to avoid any
problems with console and non-console being called together.
This should help with the SMP case as it should stop other cores being
signalled during the console write.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the meson_uart_tx_empty() instead of a direct read of the status
register. This is easier to read and will ensure the UART's transmit
state machine is idle when trying to update the baud rate.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since disabling the transmit state machine still allows characters to
be transmitted when written to the UART write FIFO, simply disable the
transmit interrupt when the UART port is stopped.
This has not shown an improvement with the console issues when running
systemd, but seems like it should be done.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reported-by: Edward Cragg <ed.cragg@codethink.co.uk>
Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ensure the UART's transmitter is enabled when meson_console_putchar is
called. If not, then the console output is corrupt (the hardware seems
to try and send /something/ even if the TX is disabled).
This fixes corrupt console output on events such as trying to reboot the
system since the console tx may be called after drivers shutdown method has
been called.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reported-by: Edward Cragg <edward.cragg@codethink.co.uk>
Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tx_empty() uart_op should only return empty if both the transmit fifo
and the transmit state-machine are both idle. Add a test for the hardware's
XMIT_BUSY flag.
Note, this is possibly related to an issue where the port is being shutdown
with paritally transmitted characters in it.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reported-by: Edward Cragg <edward.cragg@codethink.co.uk>
Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the uart startup entry is called, do not reset the port as this
could cause issues with anything left in the FIFO from a previous operation
such as a console write. Move the hardware reset to probe time and simply
clear the errors before enabling the port.
This fixes the issue where the console could become corrupted as there
where characters left in the output or output fifo when a user process
such as systemd would open/close the uart to transmit characters.
For example, you get:
[ 3.252263] systemd[1]: Dete
instead of:
[ 3.338801] systemd[1]: Detected architecture arm.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The meson_uart_release_port() unmaps the register area but does not release
it. The meson_uart_request_port() calls devm_request_mem_region so the
release should call devm_release_mem_region() for that area so that anyt
subsequent use of these calls will work.
This fixes an issue where the addition of reset code before registering
the uart stops the console from working.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function meson_uart_release_port() inappropriately try to
iounmap() a resource managed by devm_ioremap_nocache().
The function meson_uart_release_port() maybe called by uart_ioctl()
that means meson_uart_release_port() is not called from within a
probe or remove function, for safety, I convert iounmap() to
devm_iounmap().
Signed-off-by: Firo Yang <firogm@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The SoC has four fully functional UARTs which use the same programming
model. They are named UART_A, UART_B, UART_C and UART_AO (Always-On)
which cannot be powered off.
Signed-off-by: Carlo Caione <carlo@caione.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
