Commit Graph

5382 Commits

Author SHA1 Message Date
Masahiro Yamada
2fd8e45418 serial: 8250_uniphier: remove unused "fifo-size" property
The FIFO size of the UART devices is 64 on almost all UniPhier SoCs
with the exception Pro4TV SoC (MN2WS0235), which used 128 FIFO size.
However, Pro4TV SoC was never upstreamed, and out of production.

So, this property has never been used in a useful way.
Let's remove old unused code.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:58 -07:00
Wei Yongjun
823f4e53f0 serial: uartps: Fix missing unlock on error in cdns_get_id()
Add the missing unlock before return from function cdns_get_id()
in the error handling case.

Fixes: ae1cca3fa3 ("serial: uartps: Change uart ID port allocation")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:58 -07:00
Nicolas Ferre
377fedd186 tty/serial: atmel: add ISO7816 support
When mode is set in atmel_config_iso7816() we backup last RS232 mode
for coming back to this mode if requested.
Also allow setup of T=0 and T=1 parameter and basic support in set_termios
function as well.

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
[ludovic.desroches@microchip.com: rebase, add check on fidi ratio, checkpatch fixes]
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:55 -07:00
Nicolas Ferre
ad8c0eaa0a tty/serial_core: add ISO7816 infrastructure
Add the ISO7816 ioctl and associated accessors and data structure.
Drivers can then use this common implementation to handle ISO7816
(smart cards).

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
[ludovic.desroches@microchip.com: squash and rebase, removal of gpios, checkpatch fixes]
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:55 -07:00
Steve Sakoman
c550f01c81 serial:serial_core: Allow use of CTS for PPS line discipline
Add a "pps_4wire" file to serial ports in sysfs in case the kernel is
configured with CONFIG_PPS_CLIENT_LDISC. Writing 1 to the file enables
the use of CTS instead of DCD for PPS signal input. This is necessary
in case a serial port is not completely wired.
Though this affects PPS processing the patch is against the serial core
as the source of the serial port PPS event dispatching has to be
modified. Furthermore it should be possible to modify the source of
serial port PPS event dispatching before changing the line discipline.

Signed-off-by: Andreas Steinmetz <ast@domdv.de>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Tested-by: Steve Sakoman <steve@sakoman.com>
Tested-by: Eric Gallimore <egallimore@ucsd.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:55 -07:00
Greg Kroah-Hartman
669c5d8d5f Merge 4.19-rc6 into tty-next
We want the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-30 08:11:09 -07:00
Uwe Kleine-König
7e620984b6 serial: imx: restore handshaking irq for imx1
Back in 2015 when irda was dropped from the driver imx1 was broken. This
change reintroduces the support for the third interrupt of the UART.

Fixes: afe9cbb1a6 ("serial: imx: drop support for IRDA")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20 14:51:31 +02:00
Michal Simek
ae1cca3fa3 serial: uartps: Change uart ID port allocation
For IPs which have alias algorightm all the time using that alias and
minor number. It means serial20 alias ends up as ttyPS20.

If alias is not setup for probed IP instance the first unused position is
used but that needs to be checked if it is really empty because another
instance doesn't need to be probed at that time. of_alias_get_alias_list()
fills alias bitmap which exactly shows which ID is free.
If alias pointing to different not compatible IP, it is free to use.

cdns_get_id() call is placed below structure allocation to simplify
error path.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20 13:49:53 +02:00
YueHaibing
13b4353bb0 tty: serial: remove set but not used variable 'error'
Fixes gcc '-Wunused-but-set-variable' warning:

drivers/tty/serial/pmac_zilog.c: In function 'pmz_receive_chars':
drivers/tty/serial/pmac_zilog.c:222:30: warning:
 variable 'error' set but not used [-Wunused-but-set-variable]

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20 13:33:15 +02:00
Laura Abbott
1cd25cbb2f kgdboc: Fix warning with module build
After 2dd4531686 ("kgdboc: Fix restrict error"), kgdboc_option_setup is
now only used when built in, resulting in a warning when compiled as a
module:

drivers/tty/serial/kgdboc.c:134:12: warning: 'kgdboc_option_setup' defined but not used [-Wunused-function]
 static int kgdboc_option_setup(char *opt)
            ^~~~~~~~~~~~~~~~~~~

Move the function under the appropriate ifdef for builtin only.

Fixes: 2dd4531686 ("kgdboc: Fix restrict error")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20 09:17:25 +02:00
Jiri Slaby
feacbecb39 TTY: tty_buffer, warn on leaks
When we leak some tty buffer, warn about that. For that we need to
account the memory used also in the tty_buffer_free_all function. On
other locations, the accounting is handled correctly.

Note that we do not account the free list, as that was accounted in
tty_buffer_free before put on the free list.

I have been using this patch for ages, so let's see if anybody else
encounters any issues.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:25 +02:00
Tobin C. Harding
863299001b tty_port: Remove incorrect whitespace after comments
Currently there are a bunch of kernel-doc function comments that have a
line of whitespace after the comment and before the function they
comment - this is incorrect, there should be no whitespace here.

Remove incorrect whitespace between comment and associated function.

Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:25 +02:00
Phil Elwell
30ec514d44 sc16is7xx: Fix for "Unexpected interrupt: 8"
The SC16IS752 has an Enhanced Feature Register which is aliased at the
same address as the Interrupt Identification Register; accessing it
requires that a magic value is written to the Line Configuration
Register. If an interrupt is raised while the EFR is mapped in then
the ISR won't be able to access the IIR, leading to the "Unexpected
interrupt" error messages.

Avoid the problem by claiming a mutex around accesses to the EFR
register, also claiming the mutex in the interrupt handler work
item (this is equivalent to disabling interrupts to interlock against
a non-threaded interrupt handler).

See: https://github.com/raspberrypi/linux/issues/2529

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:25 +02:00
Phil Elwell
8344498721 sc16is7xx: Fix for multi-channel stall
The SC16IS752 is a dual-channel device. The two channels are largely
independent, but the IRQ signals are wired together as an open-drain,
active low signal which will be driven low while either of the
channels requires attention, which can be for significant periods of
time until operations complete and the interrupt can be acknowledged.
In that respect it is should be treated as a true level-sensitive IRQ.

The kernel, however, needs to be able to exit interrupt context in
order to use I2C or SPI to access the device registers (which may
involve sleeping).  Therefore the interrupt needs to be masked out or
paused in some way.

The usual way to manage sleeping from within an interrupt handler
is to use a threaded interrupt handler - a regular interrupt routine
does the minimum amount of work needed to triage the interrupt before
waking the interrupt service thread. If the threaded IRQ is marked as
IRQF_ONESHOT the kernel will automatically mask out the interrupt
until the thread runs to completion. The sc16is7xx driver used to
use a threaded IRQ, but a patch switched to using a kthread_worker
in order to set realtime priorities on the handler thread and for
other optimisations. The end result is non-threaded IRQ that
schedules some work then returns IRQ_HANDLED, making the kernel
think that all IRQ processing has completed.

The work-around to prevent a constant stream of interrupts is to
mark the interrupt as edge-sensitive rather than level-sensitive,
but interpreting an active-low source as a falling-edge source
requires care to prevent a total cessation of interrupts. Whereas
an edge-triggering source will generate a new edge for every interrupt
condition a level-triggering source will keep the signal at the
interrupting level until it no longer requires attention; in other
words, the host won't see another edge until all interrupt conditions
are cleared. It is therefore vital that the interrupt handler does not
exit with an outstanding interrupt condition, otherwise the kernel
will not receive another interrupt unless some other operation causes
the interrupt state on the device to be cleared.

The existing sc16is7xx driver has a very simple interrupt "thread"
(kthread_work job) that processes interrupts on each channel in turn
until there are no more. If both channels are active and the first
channel starts interrupting while the handler for the second channel
is running then it will not be detected and an IRQ stall ensues. This
could be handled easily if there was a shared IRQ status register, or
a convenient way to determine if the IRQ had been deasserted for any
length of time, but both appear to be lacking.

Avoid this problem (or at least make it much less likely to happen)
by reducing the granularity of per-channel interrupt processing
to one condition per iteration, only exiting the overall loop when
both channels are no longer interrupting.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:25 +02:00
Marek Vasut
f6aa5beb45 serial: 8250: Fix clearing FIFOs in RS485 mode again
The 8250 FIFOs indeed need to be cleared after stopping transmission in
RS485 mode without SER_RS485_RX_DURING_TX flag set. But there are two
problems with the approach taken by the previous patch from Fixes tag.

First, serial8250_clear_fifos() should clear fifos, but what it really
does is it enables the FIFOs unconditionally if present, clears them
and then sets the FCR register to zero, which effectively disables the
FIFOs. In case the FIFO is disabled, enabling it and clearing it makes
no sense and in fact can trigger misbehavior of the 8250 core. Moreover,
the FCR register may contain other FIFO configuration bits which may not
be writable unconditionally and writing them incorrectly can trigger
misbehavior of the 8250 core too. (ie. AM335x UART swallows the first
byte and retransmits the last byte twice because of this FCR write).

Second, serial8250_clear_and_reinit_fifos() completely reloads the FCR,
but what really has to happen at the end of the RS485 transmission is
clearing of the FIFOs and nothing else.

This patch repairs serial8250_clear_fifos() so that it really only
clears the FIFOs by operating on FCR[2:1] bits and leaves all the
other bits alone. It also undoes serial8250_clear_and_reinit_fifos()
from __do_stop_tx_rs485() as serial8250_clear_fifos() is sufficient.

Signed-off-by: Marek Vasut <marex@denx.de>
Fixes: 2bed8a8e70 ("Clearing FIFOs in RS485 emulation mode causes subsequent transmits to break")
Cc: Daniel Jedrychowski <avistel@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org> # let it bake a bit before merging
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:25 +02:00
Rob Herring
fff10721d8 tty: Convert to using %pOFn instead of device_node.name
In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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: linux-serial@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:25 +02:00
John Garry
a27d938251 serial: 8250_of: Fix for lack of interrupt support
In commit c58caaab3b ("serial: 8250: of: Defer probe on missing IRQ"), a
check was added for the UART driver being probed prior to the parent IRQ
controller.

Unfortunately this breaks certain boards which have no interrupt support,
like Huawei D03.

Indeed, the 8250 DT bindings state that interrupts should be supported -
not must.

To fix, switch from irq_of_parse_and_map() to of_irq_get(), which
does relay whether the IRQ host controller domain is not ready, i.e.
defer probe, instead of assuming it.

Fixes: c58caaab3b ("serial: 8250: of: Defer probe on missing IRQ")
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Tested-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:25 +02:00
Douglas Anderson
c362272bde tty: serial: qcom_geni_serial: Fix serial when not used as console
If you've got the "console" serial port setup to use just as a UART
(AKA there is no "console=ttyMSMX" on the kernel command line) then
certain initialization is skipped.  When userspace later tries to do
something with the port then things go boom (specifically, on my
system, some sort of exception hit that caused the system to reboot
itself w/ no error messages).

Let's cleanup / refactor the init so that we always run the same init
code regardless of whether we're using the console.

To make this work, we make rely on qcom_geni_serial_pm doing its job
to turn resources on.

For the record, here is a trace of the order of things (after this
patch) when console= is specified on the command line and we have an
agetty on the port:
  qcom_geni_serial_pm: 4 (undefined) => 0 (on)
  qcom_geni_console_setup
  qcom_geni_serial_port_setup
  qcom_geni_serial_console_write
  qcom_geni_serial_startup
  qcom_geni_serial_start_tx

...and here is the order of things (after this patch) when console= is
_NOT_ specified on the command line and we have an agetty port:
  qcom_geni_serial_pm: 4 => 0
  qcom_geni_serial_pm: 0 => 3
  qcom_geni_serial_pm: 3 => 0
  qcom_geni_serial_startup
  qcom_geni_serial_port_setup
  qcom_geni_serial_pm: 0 => 3
  qcom_geni_serial_pm: 3 => 0
  qcom_geni_serial_startup
  qcom_geni_serial_start_tx

Fixes: c4f528795d ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Geert Uytterhoeven
2843cbb5d3 tty: serial: qcom_geni_serial: Drop useless check for dev.of_node
With gcc 4.1.2:

    drivers/tty/serial/qcom_geni_serial.c: In function ‘qcom_geni_serial_probe’:
    drivers/tty/serial/qcom_geni_serial.c:1261: warning: ‘drv’ may be used uninitialized in this function

Indeed, if dev.of_node is NULL, drv will be used uninitialized, and
dereferenced in uart_add_one_port().  However, as this driver supports
DT only, dev.of_node will always be valid.

Hence remove the useless check for dev.of_node, killing the warning as a
side effect.

Fixes: 8a8a66a1a1 ("tty: serial: qcom_geni_serial: Add support for flow control")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Anton Vasilyev
5963e8a312 serial: mxs-auart: Fix potential infinite loop
On the error path of mxs_auart_request_gpio_irq() is performed
backward iterating with index i of enum type. Underline enum type
may be unsigned char. In this case check (--i >= 0) will be always
true and error handling goes into infinite loop.

The patch changes the check so that it is valid for signed and unsigned
types.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Anton Vasilyev <vasilyev@ispras.ru>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Baolin Wang
d2de9601eb serial: sprd: Fix the indentation issue
Make the macros' definition and code have the same correct indentation.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Acked-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Baolin Wang
dd22161eef serial: sprd: Change 'int' to 'unsigned int'
The register offset value should be 'unsigned int' type.

Moreover, prefer 'unsigned int' to bare use of 'unsigned'.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Acked-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Baolin Wang
262d3dc007 serial: sprd: Remove unnecessary resource validation
The devm_ioremap_resource() will valid the resources, thus remove the
unnecessary resource validation in the driver.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Acked-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Baolin Wang
2b5a997386 serial: sprd: Use readable macros instead of magic number
Define readable macros instead of magic number to make code more readable.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Acked-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Baolin Wang
20464f3a9b serial: sprd: Remove unused structure
Remove the unused reg_backup structure.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Acked-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Lokesh Vutla
c886751465 serial: 8250_omap: Make 8250_omap driver driver depend on ARCH_K3
Allow 8250 omap serial driver to be used for K3 platforms.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Marek Szyprowski
1ff3652bc7 serial: samsung: Enable baud clock for UART reset procedure in resume
Ensure that the baud clock is also enabled for UART register writes in
driver resume. On Exynos5433 SoC this is needed to avoid external abort
issue.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Chris Brandt
3d8b43ad9c serial: sh-sci: Add earlycon for R7S9210
Since the register offsets are different for RZ/A2 SCIF, we need
to declare a separate string for it.

Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Geert Uytterhoeven
a1c2fd7e10 Revert "serial: sh-sci: Allow for compressed SCIF address"
This reverts commit 2d4dd0da45.

This broke earlycon on all Renesas ARM platforms using a SCIF port for the
serial console (R-Car, RZ/A1, RZ/G1, RZ/G2 SoCs), due to an incorrect value
of port->regshift.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Geert Uytterhoeven
10c63443b7 Revert "serial: sh-sci: Remove SCIx_RZ_SCIFA_REGTYPE"
This reverts commit 7acece71a5.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Anson Huang
fcfed1be53 tty: serial: imx: add pinctrl sleep/default mode switch for suspend
On some i.MX SoCs' low power mode, such as i.MX7D's LPSR(low power
state retention), UART iomux settings will be lost, need to add
pinctrl sleep/default mode switch during suspend/resume to make
sure UART iomux settings are correct after resume.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Anson Huang
07b5e16e98 tty: serial: imx: add lock for registers save/restore
In noirq suspend/resume stage with no_console_suspend enabled,
imx_uart_console_write() may be called to print out log_buf
message by printk(), so there will be race condition between
imx_uart_console_write() and imx_uart_save/restore_context(),
need to add lock to protect the registers save/restore operations.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
jun qian
c974991d26 tty:serial:imx: use spin_lock instead of spin_lock_irqsave in isr
Before the program enters the uart ISR, the local interrupt has been
disabled by the system, so it's not appropriate to use spin_lock_irqsave
interface in the ISR.

Signed-off-by: jun qian <hangdianqj@163.com>
Reviewed-by: Barry Song <21cnbao@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Shubhrajyoti Datta
deeb33e8fd tty: serial: uartlite: Use dynamic array for console port
Driver console functions are using pointer to static array with fixed
size. There can be only one serial console at the time which is found
by register_console(). register_console() is filling cons->index to
port->line value.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Shubhrajyoti Datta
5f6825d1ce tty: serial: uartlite: remove console_init
register_console is called twice once from

uart_add_one_port -> uart_configure_port
remove the double call

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Shubhrajyoti Datta
415b43bdb0 tty: serial: uartlite: Move uart register to probe
Move uart register to probe.
This is in preparation of removing the hardcoding of number of uarts.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Shubhrajyoti Datta
ea42d7a67a tty: serial: uartlite: Enable clocks at probe
At probe the uartlite is getting configured.
Enable the clocks before assiging uart and
disable after probe is done.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Sebastian Andrzej Siewior
9d7c249a1e serial: 8250: drop the printk from serial8250_interrupt()
The printk() in serial8250_interrupt() was once hidden behind a debug
macro in commit f4f653e987 ("serial: 8250, disable "too much work"
messages") and reverted back in commit 12de375ec4 ("Revert "serial:
8250, disable "too much work" messages"").

This was introduced first in 0.99.13k with the "serial" driver itself
(and called pass_number with a limit of 64 and no print). In 1.1.13 it
was renamed to pass_counter and the printk was behind #if 0. In 1.1.94
the limit of 64 was increased to 256 and hidden behind
RS_ISR_PASS_LIMIT. With this change the #if 0 turned into #if 1. It
slowly become what we have today with a loop limit of 512.

Usually, that printk isn't hit. However on KVM with a busy UART and
overloaded host it might happen. It is also likely with threaded
interrupts and a task which preempts the interrupt handler.

If the UART has (legitimate) work to do and we break out of the loop,
nothing changes: the interrupt is most likely already pending in the
interrupt controller and we end up in the handler anyway. This printk is
hardly helping.

Older kernels also had a comment saying that a bad configuration might
lead to this but I don't see how that should happen because a wrongly
configured interrupt number would let the handler leave "early" with
IRQ_NONE and the spurious detected will handle that (weill since 2.6.11,
before that we had no spurious detector). In that case, we would never
loop that often here.

This loop looks like an optimisation in order to pull the bytes from the
FIFO which were received while we were already here instead of waiting
for the interrupt. This might have been a good idea while the CPUs were
slow and FIFOs small.
There are other serial driver in tree, like the amba-pl*, which also
have this kind of a loop but without the printk (and were based on this
driver).

Remove the printk which might trigger in otherwise valid situtations.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Laura Abbott
2dd4531686 kgdboc: Fix restrict error
There's an error when compiled with restrict:

drivers/tty/serial/kgdboc.c: In function ‘configure_kgdboc’:
drivers/tty/serial/kgdboc.c:137:2: error: ‘strcpy’ source argument is the same
as destination [-Werror=restrict]
  strcpy(config, opt);
  ^~~~~~~~~~~~~~~~~~~

As the error implies, this is from trying to use config as both source and
destination. Drop the call to the function where config is the argument
since nothing else happens in the function.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
He Zhe
39724d56a0 kgdboc: Change printk to the right fashion
pr_* is preferred according to scripts/checkpatch.pl.

Cc: jason.wessel@windriver.com
Cc: gregkh@linuxfoundation.org
Cc: jslaby@suse.com
Signed-off-by: He Zhe <zhe.he@windriver.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
He Zhe
1bd54d851f kgdboc: Passing ekgdboc to command line causes panic
kgdboc_option_setup does not check input argument before passing it
to strlen. The argument would be a NULL pointer if "ekgdboc", without
its value, is set in command line and thus cause the following panic.

PANIC: early exception 0xe3 IP 10:ffffffff8fbbb620 error 0 cr2 0x0
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.18-rc8+ #1
[    0.000000] RIP: 0010:strlen+0x0/0x20
...
[    0.000000] Call Trace
[    0.000000]  ? kgdboc_option_setup+0x9/0xa0
[    0.000000]  ? kgdboc_early_init+0x6/0x1b
[    0.000000]  ? do_early_param+0x4d/0x82
[    0.000000]  ? parse_args+0x212/0x330
[    0.000000]  ? rdinit_setup+0x26/0x26
[    0.000000]  ? parse_early_options+0x20/0x23
[    0.000000]  ? rdinit_setup+0x26/0x26
[    0.000000]  ? parse_early_param+0x2d/0x39
[    0.000000]  ? setup_arch+0x2f7/0xbf4
[    0.000000]  ? start_kernel+0x5e/0x4c2
[    0.000000]  ? load_ucode_bsp+0x113/0x12f
[    0.000000]  ? secondary_startup_64+0xa5/0xb0

This patch adds a check to prevent the panic.

Cc: stable@vger.kernel.org
Cc: jason.wessel@windriver.com
Cc: gregkh@linuxfoundation.org
Cc: jslaby@suse.com
Signed-off-by: He Zhe <zhe.he@windriver.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Michal Simek
6ac1b91f34 serial: uartps: Enable automatic flow control
Enable automatic flow control which should ensure that there is no
mainteinance in connection for zcu100 BT case.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Michal Simek
bed25ac0e2 serial: uartps: Move Port ID to device data structure
Record port ID in device data structure to be have it connected to
certain instance.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Michal Simek
024ca329bf serial: uartps: Register own uart console and driver structures
Every instance is registering own struct console and struct uart_driver
with minor number which corresponds to alias ID (or 0 now) and with 1 uart
port. The same alias ID is saved to tty_driver->name_base which is key
field for creating ttyPSX name.

Because name_base and minor number are setup already there is no need to
setup any port->line number because 0 is the right value.

Unfortunately this driver is setting up major number to 0 for using
dynamic assignment and kernel is allocating different major numbers for
every instance instead of using the same major and different minor
number.

~# ls -la /dev/ttyPS*
crw-------    1 root     root      252,   0 Jan  1 03:36 /dev/ttyPS0
crw--w----    1 root     root      253,   1 Jan  1 00:00 /dev/ttyPS1

When major number is not 0. For example 252 then major/minor
combinations are in expected form

~# ls -la /dev/ttyPS*
crw-------    1 root     root      252,   0 Jan  1 04:04 /dev/ttyPS0
crw--w----    1 root     root      252,   1 Jan  1 00:00 /dev/ttyPS1

Driver is not freeing struct cdns_uart_console in case that instance is
not used as console. The reason is that console is incorrectly unregistred
and "console [0] disabled" message will be shown.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Michal Simek
427c8ae9be serial: uartps: Change logic how console_port is setup
Change logic how console_port is setup by using CON_ENABLED flag
instead of index. There will be unique cdns_uart_console() structures
that's why code can't use id for console_port assignment.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Michal Simek
10a5315b47 serial: uartps: Fill struct uart_driver in probe()
This is preparation step for dynamic port allocation without
CDNS_UART_NR_PORTS macro. Fill the structure only once at probe.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Michal Simek
e4bbb5194e serial: uartps: Move register to probe based on run time detection
Register uart driver in probe to be able to register one device with
unique major/minor separately. Also calculate number of instances of
this driver to be able to call uart_unregister_driver() when there is no
instance.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:22 +02:00
Michal Simek
14090ad180 serial: uartps: Move alias reading higher in probe()
This cosmetic change is done only for having next patch much easier to
read. Moving id setup higher in probe is not affecting any usage of this
driver and it also simplify error path.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:22 +02:00
Michal Simek
46a460f015 serial: uartps: Do not use static struct uart_driver out of probe()
cdns_uart_suspend()/resume() and remove() are using static reference
to struct uart_driver. Assign this reference to private data structure
as preparation step for dynamic struct uart_driver allocation.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:22 +02:00
Nava kishore Manne
4b9d33c6a3 serial: uartps: Fix suspend functionality
The driver's suspend/resume functions were buggy.
If UART node contains any child node in the DT and
the child is established a communication path with
the parent UART. The relevant /dev/ttyPS* node will
be not available for other operations.
If the driver is trying to do any operations like
suspend/resume without checking the tty->dev status
it leads to the kernel crash/hang.

This patch fix this issue by call the device_may_wake()
with the generic parameter of type struct device.
in the uart suspend and resume paths.

It also fixes a race condition in the uart suspend
path(i.e uart_suspend_port() should be called at the
end of cdns_uart_suspend API this path updates the same)

Signed-off-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:22 +02:00