3992 Commits

Author SHA1 Message Date
Geert Uytterhoeven
202dc3cc10 serial: sh-sci: Fix receive on SCIFA/SCIFB variants with DMA
On SCIFA and SCIFB serial ports with DMA support (i.e. some ports on
R-Car Gen2 and RZ/G1 SoCs), receive DMA operations are submitted before
the DMA channel pointer is initialized.  Hence this fails, and the
driver tries to fall back to PIO.  However, at this early phase in the
initialization sequence, fallback to PIO does not work, leading to a
serial port that cannot receive any data.

Fix this by calling sci_submit_rx() after initialization of the DMA
channel pointer.

Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Fixes: 2c4ee23530ffc022 ("serial: sh-sci: Postpone DMA release when falling back to PIO")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-15 16:20:24 +02:00
Michal Simek
59eaeba63a of: base: Change logic in of_alias_get_alias_list()
Check compatible string first before setting up bit in bitmap to also
cover cases that allocated bitfield is not big enough.
Show warning about it but let driver to continue to work with allocated
bitfield to keep at least some devices (included console which
is commonly close to serial0) to work.

Fixes: b1078c355d76 ("of: base: Introduce of_alias_get_alias_list() to check alias IDs")
Fixes: ae1cca3fa347 ("serial: uartps: Change uart ID port allocation")
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-15 16:16:06 +02:00
Ulrich Hecht
c58a3ae58b serial: sh-sci: do not warn if DMA transfers are not supported
Not all (H)SCIF devices support DMA, and failure to set it up is not
normally a cause for concern. This patch demotes the associated warning to
debug output.

Inspired by BSP patch "sci: sh-sci: Fix transfer sequence of unsupport DMA
transfer" (6beb1f98d3bd30) by Hiromitsu Yamasaki.

Signed-off-by: Ulrich Hecht <uli+renesas@fpond.eu>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-15 16:14:48 +02:00
Al Viro
7ee3296551 kill TIOCSER[SG]WILD
the only user is very old setserial rc script and even that
(as far back as MCC Interim, AFAICS) doesn't actually fail -
just gives one message during the boot ("Cannot scan for wild
interrupts") and proceeds past that just fine.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-10-13 00:50:52 -04:00
Al Viro
5099d234a5 serial_core: switch to ->[sg]et_serial()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-10-13 00:50:33 -04:00
Michal Simek
2088cfd882 serial: uartps: Do not allow use aliases >= MAX_UART_INSTANCES
Aliases >= MAX_UART_INSTANCES is no problem to find out and use but in
error path is necessary skip clearing bits in bitmap to ensure that only
bits in allocated bitmap are handled and nothing beyond that.
Without this patch when for example serial90 alias is used then in error
patch bit 90 is clear in 32bit wide bitmap.

Fixes: ae1cca3fa347 ("serial: uartps: Change uart ID port allocation")
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 19:59:29 +02:00
Greg Kroah-Hartman
834d3cd294 Fix open-coded multiplication arguments to allocators
- Fixes several new open-coded multiplications added in the 4.19 merge window.
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Merge tag 'alloc-args-v4.19-rc8' of https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Kees writes:
  "Fix open-coded multiplication arguments to allocators

   - Fixes several new open-coded multiplications added in the 4.19
     merge window."

* tag 'alloc-args-v4.19-rc8' of https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  treewide: Replace more open-coded allocation size multiplications
2018-10-11 19:10:30 +02:00
Vabhav Sharma
3bc3206e1c serial: fsl_lpuart: Remove the alias node dependence
Numbering the ttyLPn space should not depend on the generic name
"serial<n>".

If don't add the alias node like:"serial0 = &lpuart0;", then lpuart
will probe failed:
[    0.773410] fsl-lpuart 2950000.serial: failed to get alias id, errno -19

So remove the alias node dependence, and add the support for allocate the
line port automatically.

Signed-off-by: Yuan Yao <yao.yuan@nxp.com>
Signed-off-by: Vabhav Sharma <vabhav.sharma@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-10 13:16:48 +02:00
Greg Kroah-Hartman
4e1a606d55 Merge 4.19-rc7 into tty-next
We want the fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-08 15:43:12 +02:00
Kees Cook
329e098939 treewide: Replace more open-coded allocation size multiplications
As done treewide earlier, this catches several more open-coded
allocation size calculations that were added to the kernel during the
merge window. This performs the following mechanical transformations
using Coccinelle:

	kvmalloc(a * b, ...) -> kvmalloc_array(a, b, ...)
	kvzalloc(a * b, ...) -> kvcalloc(a, b, ...)
	devm_kzalloc(..., a * b, ...) -> devm_kcalloc(..., a, b, ...)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-10-05 18:06:30 -07:00
Lance Roy
8ebfe885c6 TTY: sn_console: Replace spin_is_locked() with spin_trylock()
sn_sal_console_write() used spin_is_locked() + spin_lock() to get
achieve the same thing as a spin_trylock(), so simplify it by using that
instead. This is also a step towards possibly removing spin_is_locked().

Signed-off-by: Lance Roy <ldr709@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: <linux-serial@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-04 11:06:35 -07:00
Greg Kroah-Hartman
817e9bc8cc Revert "serial:serial_core: Allow use of CTS for PPS line discipline"
This reverts commit c550f01c810f2197c98e6e3103f81797f5e063be.

Turns out the samsung tty driver is mucking around in the "unused" port
fields and this patch breaks that code :(

So we need to fix that driver up before this can be accepted.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-04 09:57:45 -07:00
Geert Uytterhoeven
5b162cc4ac Revert "serial: sh-sci: Allow for compressed SCIF address"
This reverts commit 2d4dd0da45401c7ae7332b4d1eb7bbb1348edde9.

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>
2018-10-02 14:38:16 -07:00
Geert Uytterhoeven
1065302245 Revert "serial: sh-sci: Remove SCIx_RZ_SCIFA_REGTYPE"
This reverts commit 7acece71a517cad83a0842a94d94c13f271b680c.

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>
2018-10-02 14:38:02 -07:00
Guenter Roeck
beeeac43b6 Revert "serial: 8250_dw: Fix runtime PM handling"
This reverts commit d76c74387e1c978b6c5524a146ab0f3f72206f98.

While commit d76c74387e1c ("serial: 8250_dw: Fix runtime PM handling")
fixes runtime PM handling when using kgdb, it introduces a traceback for
everyone else.

BUG: sleeping function called from invalid context at
	/mnt/host/source/src/third_party/kernel/next/drivers/base/power/runtime.c:1034
in_atomic(): 1, irqs_disabled(): 1, pid: 1, name: swapper/0
7 locks held by swapper/0/1:
 #0: 000000005ec5bc72 (&dev->mutex){....}, at: __driver_attach+0xb5/0x12b
 #1: 000000005d5fa9e5 (&dev->mutex){....}, at: __device_attach+0x3e/0x15b
 #2: 0000000047e93286 (serial_mutex){+.+.}, at: serial8250_register_8250_port+0x51/0x8bb
 #3: 000000003b328f07 (port_mutex){+.+.}, at: uart_add_one_port+0xab/0x8b0
 #4: 00000000fa313d4d (&port->mutex){+.+.}, at: uart_add_one_port+0xcc/0x8b0
 #5: 00000000090983ca (console_lock){+.+.}, at: vprintk_emit+0xdb/0x217
 #6: 00000000c743e583 (console_owner){-...}, at: console_unlock+0x211/0x60f
irq event stamp: 735222
__down_trylock_console_sem+0x4a/0x84
console_unlock+0x338/0x60f
__do_softirq+0x4a4/0x50d
irq_exit+0x64/0xe2
CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5 #6
Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.286.0 03/15/2017
Call Trace:
 dump_stack+0x7d/0xbd
 ___might_sleep+0x238/0x259
 __pm_runtime_resume+0x4e/0xa4
 ? serial8250_rpm_get+0x2e/0x44
 serial8250_console_write+0x44/0x301
 ? lock_acquire+0x1b8/0x1fa
 console_unlock+0x577/0x60f
 vprintk_emit+0x1f0/0x217
 printk+0x52/0x6e
 register_console+0x43b/0x524
 uart_add_one_port+0x672/0x8b0
 ? set_io_from_upio+0x150/0x162
 serial8250_register_8250_port+0x825/0x8bb
 dw8250_probe+0x80c/0x8b0
 ? dw8250_serial_inq+0x8e/0x8e
 ? dw8250_check_lcr+0x108/0x108
 ? dw8250_runtime_resume+0x5b/0x5b
 ? dw8250_serial_outq+0xa1/0xa1
 ? dw8250_remove+0x115/0x115
 platform_drv_probe+0x76/0xc5
 really_probe+0x1f1/0x3ee
 ? driver_allows_async_probing+0x5d/0x5d
 driver_probe_device+0xd6/0x112
 ? driver_allows_async_probing+0x5d/0x5d
 bus_for_each_drv+0xbe/0xe5
 __device_attach+0xdd/0x15b
 bus_probe_device+0x5a/0x10b
 device_add+0x501/0x894
 ? _raw_write_unlock+0x27/0x3a
 platform_device_add+0x224/0x2b7
 mfd_add_device+0x718/0x75b
 ? __kmalloc+0x144/0x16a
 ? mfd_add_devices+0x38/0xdb
 mfd_add_devices+0x9b/0xdb
 intel_lpss_probe+0x7d4/0x8ee
 intel_lpss_pci_probe+0xac/0xd4
 pci_device_probe+0x101/0x18e
...

Revert the offending patch until a more comprehensive solution
is available.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Fixes: d76c74387e1c ("serial: 8250_dw: Fix runtime PM handling")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 14:35:10 -07:00
Dai Okamura
aad2d4952d serial: 8250_uniphier: add auto-flow-control support
Add selective auto-flow-control support for UniPhier serial driver.

Signed-off-by: Dai Okamura <okamura.dai@socionext.com>
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
Masahiro Yamada
aca70d19c8 serial: 8250_uniphier: flatten probe function
Currently, the DT-related settings are split out to
uniphier_of_serial_setup(), but it turned out to be not nice.
The next commit will add a DT property, but it will not fit in
the helper.  Merge the helper into the probe function.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:58 -07:00
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: ae1cca3fa347 ("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: afe9cbb1a6ad ("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 2dd453168643 ("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: 2dd453168643 ("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
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: 2bed8a8e7072 ("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 c58caaab3bf8 ("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: c58caaab3bf8 ("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: c4f528795d1a ("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: 8a8a66a1a18a1dbd ("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 2d4dd0da45401c7ae7332b4d1eb7bbb1348edde9.

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 7acece71a517cad83a0842a94d94c13f271b680c.

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