The port->console flag is always false, as uart_console() is called
before the serial console has been registered.
Hence for a serial port used as the console, uart_tty_port_shutdown()
will still be called when userspace closes the port, powering it down.
This may lead to a system lock up when the serial console driver writes
to the serial port's registers.
To fix this, move the setting of port->console after the call to
uart_configure_port(), which registers the serial console.
Fixes: 761ed4a945 ("tty: serial_core: convert uart_close to use tty_port_close")
Reported-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Tested-by: Mugunthan V N <mugunthanvnm@ti.com>
Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
[robh: rebased on tty-linus]
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After commit 1cf6e8fc83 ("tty/serial: at91: fix RTS line management
when hardware handshake is enabled"), the hardware handshake wasn't
functional anymore on Atmel platforms (beside SAMA5D2).
To understand why, one has to understand the flag ATMEL_US_USMODE_HWHS
first:
Before commit 1cf6e8fc83 ("tty/serial: at91: fix RTS line management
when hardware handshake is enabled"), this flag was never set.
Thus, the CTS/RTS where only handled by serial_core (and everything
worked just fine).
This commit introduced the use of the ATMEL_US_USMODE_HWHS flag,
enabling it for all boards when the user space enables flow control.
When the ATMEL_US_USMODE_HWHS is set, the Atmel USART controller
handles a part of the flow control job:
- disable the transmitter when the CTS pin gets high.
- drive the RTS pin high when the DMA buffer transfer is completed or
PDC RX buffer full or RX FIFO is beyond threshold. (depending on the
controller version).
NB: This feature is *not* mandatory for the flow control to work.
(Nevertheless, it's very useful if low latencies are needed.)
Now, the specifics of the ATMEL_US_USMODE_HWHS flag:
- For platforms with DMAC and no FIFOs (sam9x25, sam9x35, sama5D3,
sama5D4, sam9g15, sam9g25, sam9g35)* this feature simply doesn't work.
( source: https://lkml.org/lkml/2016/9/7/598 )
Tested it on sam9g35, the RTS pins always stays up, even when RXEN=1
or a new DMA transfer descriptor is set.
=> ATMEL_US_USMODE_HWHS must not be used for those platforms
- For platforms with a PDC (sam926{0,1,3}, sam9g10, sam9g20, sam9g45,
sam9g46)*, there's another kind of problem. Once the flag
ATMEL_US_USMODE_HWHS is set, the RTS pin can't be driven anymore via
RTSEN/RTSDIS in USART Control Register. The RTS pin can only be driven
by enabling/disabling the receiver or setting RCR=RNCR=0 in the PDC
(Receive (Next) Counter Register).
=> Doing this is beyond the scope of this patch and could add other
bugs, so the original (and working) behaviour should be set for those
platforms (meaning ATMEL_US_USMODE_HWHS flag should be unset).
- For platforms with a FIFO (sama5d2)*, the RTS pin is driven according
to the RX FIFO thresholds, and can be also driven by RTSEN/RTSDIS in
USART Control Register. No problem here.
(This was the use case of commit 1cf6e8fc83 ("tty/serial: at91: fix
RTS line management when hardware handshake is enabled"))
NB: If the CTS pin declared as a GPIO in the DTS, (for instance
cts-gpios = <&pioA PIN_PB31 GPIO_ACTIVE_LOW>), the transmitter will be
disabled.
=> ATMEL_US_USMODE_HWHS flag can be set for this platform ONLY IF the
CTS pin is not a GPIO.
So, the only case when ATMEL_US_USMODE_HWHS can be enabled is when
(atmel_use_fifo(port) &&
!mctrl_gpio_to_gpiod(atmel_port->gpios, UART_GPIO_CTS))
Tested on all Atmel USART controller flavours:
AT91SAM9G35-CM (DMAC flavour), AT91SAM9G20-EK (PDC flavour),
SAMA5D2xplained (FIFO flavour).
* the list may not be exhaustive
Cc: <stable@vger.kernel.org> #4.4+ (beware, missing atmel_port variable)
Fixes: 1cf6e8fc83 ("tty/serial: at91: fix RTS line management when hardware handshake is enabled")
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The regmap_update first reads the IOState register and then triggers
a write if needed. However, GPIOS might be configured as an input so
the read to IOState on this GPIO is the current state which might
be random.
Signed-off-by: Francois Berder <Francois.Berder@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the case where head == 0 on the circular buffer, there should be one
DMA buffer, not two. The second zero-length buffer would break the
lpuart driver, transfer would never complete.
Signed-off-by: Aaron Brice <aaron.brice@datasoft.com>
Acked-by: Stefan Agner <stefan@agner.ch>
Tested-by: Stefan Agner <stefan@agner.ch>
Tested-by: Bhuvanchandra DV <bhuvanchandra.dv@toradex.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fintek F81865 is a LPC to 6 UARTs SuperIO. It has less functional UARTs
likes F81866. It's also need check the IRQ mode with system assigned,
but the configuration is not the same with F81216 series.
F81865 IRQ Mode setting:
0xf0
Bit1: IRQ_MODE0
Bit0: Share mode (always on)
Level/Low: IRQ_MODE0:0
Edge/High: IRQ_MODE0:1
The following list is brief descriptions of F81865:
F81865 (0704)
9Bit(not implements with mainline)
RS485(implemented)
Suggested-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fintek F81866 is a LPC to 6 UARTs SuperIO. It has fully functional UARTs
likes F81216H. It's also need check the IRQ mode with system assigned,
but the configuration is not the same with F81216 series.
F81866 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
The following list is brief descriptions of F81866:
F81866 (1010)
9Bit/High baud rate(not implements with mainline)
RS485, 128Bytes FIFO (implemented)
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fintek F81216 is a LPC to 4 UARTs device. It's the F81216 series but
support less functional than F81216AD/F81216H
The following list is brief descriptions of F81216 series:
F81216H (0105)
9Bit/High baud rate(not implements with mainline)
RS485, 128Bytes FIFO (implemented)
F81216AD (0216)
9Bit(not implements with mainline)
RS485(implemented)
F81216 (0208)
basically 16550A
Suggested-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Fintek F81216H had maximum 128Bytes FIFO, but some BIOS configurated
as normal 16Bytes FIFO. This patch will set 128Bytes FIFO and trigger
level multiplier as 4x when F81216H detected.
Default 16550A trigger level is 8Bytes. When this patch applied, the
trigger level will change to 8Byte x 4 = 32Byte. It can be reduce the RX
incoming interrupts.
Suggested-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Set IRQ Mode when port probed in probe_setup_port()
It should hold the IO port premission via fintek_8250_enter_key() and
release via fintek_8250_exit_key() when we configure the SuperIO.
This patch will move all SuperIO configure operations to
probe_setup_port() to reduce fintek_8250_enter_key() and
fintek_8250_exit_key() usage.
Suggested-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If we need to access SuperIO registers, It should write register offset
to base_addr and read/write value to base_addr + 1 to perform read/write.
We can make it more simply with write/read functions.
This patch add sio_read_reg()/sio_write_reg()/sio_write_mask_reg() to
reduce SuperIO register operation with lot of outb()/inb().
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Transfer the device-tree pxa uart handling from 8250_of to the new
8250_pxa. As a corollary, add the early console definition into
8250_pxa.
This enables to have the same uart node for the early console and the
normal uart.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The use of IRQF_ONESHOT when registering an interrupt handler with
request_irq() is non-sensical.
Not only that, it also prevents the handler from being threaded when it
otherwise should be w/ IRQ_FORCED_THREADING is enabled. This causes the
following deadlock observed by Sean Nyekjaer on -rt:
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
[..]
rt_spin_lock_slowlock from queue_kthread_work
queue_kthread_work from sc16is7xx_irq
sc16is7xx_irq [sc16is7xx] from handle_irq_event_percpu
handle_irq_event_percpu from handle_irq_event
handle_irq_event from handle_level_irq
handle_level_irq from generic_handle_irq
generic_handle_irq from mxc_gpio_irq_handler
mxc_gpio_irq_handler from mx3_gpio_irq_handler
mx3_gpio_irq_handler from generic_handle_irq
generic_handle_irq from __handle_domain_irq
__handle_domain_irq from gic_handle_irq
gic_handle_irq from __irq_svc
__irq_svc from rt_spin_unlock
rt_spin_unlock from kthread_worker_fn
kthread_worker_fn from kthread
kthread from ret_from_fork
Fixes: 9e6f4ca3e5 ("sc16is7xx: use kthread_worker for tx_work and irq")
Reported-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Josh Cartwright <joshc@ni.com>
Cc: linux-rt-users@vger.kernel.org
Cc: Jakub Kicinski <moorray3@wp.pl>
Cc: stable@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Julia Cartwright <julia@ni.com>
Acked-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need to set PCI bus mastering when device is not doing any DMA.
Though on Intel Quark DMA is a part of UART IP and thus shares same device in
Linux kernel.
Enable bus mastering only for Quark case.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fsl_lpuart cannot be used with kgdb because the kgdb
initcall is called before the driver's init.
Move kgdb to be initialized after all serial drivers
have been inited.
Signed-off-by: Nicolae Rosia <nicolae_rosia@mentor.com>
Signed-off-by: Stefan Golinschi <stefan.golinschi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds function pl011_console_match() that implements
method match of struct console. It allows to match consoles against
data specified in a string, for example taken from command line or
compiled by ACPI SPCR table handler.
This patch was merged to tty-next but then reverted because of
conflict with
commit 46e36683f4 ("serial: earlycon: Extend earlycon command line option to support 64-bit addresses")
Now it is fixed.
Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Tested-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit 4fe0d15488 ("PCI: Use positive flags in pci_alloc_irq_vectors()")
replaces flags from negative to positive values which makes mandatory to have
the last argument in pci_alloc_irq_vectors() non-zero (if we want to be no-op).
This basically drops MSI enabling in 8250_lpss driver.
Restore desired behaviour in 8250_lpss by passing PCI_IRQ_ALL_TYPES instead of
0 to pci_alloc_irq_vectors().
Fixes: 60a9244a5d ("serial: 8250_lpss: enable MSI for Intel Quark")
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pxa2xx-uart was a separate uart platform driver. It was declaring
the same device names and numbers as 8250 driver. As a result,
it was impossible to use 8250 driver on PXA SoCs.
Upon closer examination pxa2xx-uart turned out to be a clone of
8250_core driver.
Workaround for Erratum #19 according to Marvel(R) PXA270M Processor
Specification Update (April 19, 2010) is dropped. 8250_core reads
from FIFO immediately after checking DR bit in LSR.
The patch leaves the original SERIAL_PXA driver around. The original
driver is just marked DEPRECATED in Kconfig and C source. When
the original driver is considered safe to remove, no changes
to SERIAL_8250 will be necessary.
Compiling SERIAL_8250_CONSOLE and SERIAL_PXA_CONSOLE even without
SERIAL_8250_PXA breaks console for SERIAL_PXA. For this reasons, the new
and the original drivers are made mutually exclusive.
Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
CC: Heikki Krogerus <heikki.krogerus@linux.intel.com>
CC: James Cameron <quozl@laptop.org>
CC: Robert Jarzmik <robert.jarzmik@free.fr>
CC: Russell King <linux@arm.linux.org.uk>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
[rebased on v4.8]
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At this point, 'value' is always a byte, then this code is clearing
bit 15, which is already clear. I meant to clear bit 7.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reported-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch Adds the new compatible string for ZynqMP SoC.
Signed-off-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If NO_DMA=y:
drivers/built-in.o: In function `stm32_serial_remove':
stm32-usart.c:(.text+0xcea1a): undefined reference to `bad_dma_ops'
stm32-usart.c:(.text+0xcea7a): undefined reference to `bad_dma_ops'
Add a dependency on HAS_DMA to fix this.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Alexandre Torgue <alexandre.torgue@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/serial/stm32-usart.c: In function ‘stm32_receive_chars’:
drivers/tty/serial/stm32-usart.c:130: warning: comparison is always true due to limited range of data type
drivers/tty/serial/stm32-usart.c: In function ‘stm32_tx_dma_complete’:
drivers/tty/serial/stm32-usart.c:177: warning: comparison is always false due to limited range of data type
stm32_usart_offsets.icr is u8, while UNDEF_REG = ~0 is int, and thus
0xffffffff.
As all registers in stm32_usart_offsets are u8, change the definition of
UNDEF_REG to 0xff to fix this.
Fixes: ada8618ff3 ("serial: stm32: adding support for stm32f7")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A good practice is to prefix the names of functions by the name
of the subsystem.
The kthread worker API is a mix of classic kthreads and workqueues. Each
worker has a dedicated kthread. It runs a generic function that process
queued works. It is implemented as part of the kthread subsystem.
This patch renames the existing kthread worker API to use
the corresponding name from the workqueues API prefixed by
kthread_:
__init_kthread_worker() -> __kthread_init_worker()
init_kthread_worker() -> kthread_init_worker()
init_kthread_work() -> kthread_init_work()
insert_kthread_work() -> kthread_insert_work()
queue_kthread_work() -> kthread_queue_work()
flush_kthread_work() -> kthread_flush_work()
flush_kthread_worker() -> kthread_flush_worker()
Note that the names of DEFINE_KTHREAD_WORK*() macros stay
as they are. It is common that the "DEFINE_" prefix has
precedence over the subsystem names.
Note that INIT() macros and init() functions use different
naming scheme. There is no good solution. There are several
reasons for this solution:
+ "init" in the function names stands for the verb "initialize"
aka "initialize worker". While "INIT" in the macro names
stands for the noun "INITIALIZER" aka "worker initializer".
+ INIT() macros are used only in DEFINE() macros
+ init() functions are used close to the other kthread()
functions. It looks much better if all the functions
use the same scheme.
+ There will be also kthread_destroy_worker() that will
be used close to kthread_cancel_work(). It is related
to the init() function. Again it looks better if all
functions use the same naming scheme.
+ there are several precedents for such init() function
names, e.g. amd_iommu_init_device(), free_area_init_node(),
jump_label_init_type(), regmap_init_mmio_clk(),
+ It is not an argument but it was inconsistent even before.
[arnd@arndb.de: fix linux-next merge conflict]
Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull tty and serial updates from Greg KH:
"Here is the big tty and serial patch set for 4.9-rc1.
It also includes some drivers/dma/ changes, as those were needed by
some serial drivers, and they were all acked by the DMA maintainer.
Also in here is the long-suffering ACPI SPCR patchset, which was
passed around from maintainer to maintainer like a hot-potato. Seems I
was the sucker^Wlucky one. All of those patches have been acked by the
various subsystem maintainers as well.
All of this has been in linux-next with no reported issues"
* tag 'tty-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (111 commits)
Revert "serial: pl011: add console matching function"
MAINTAINERS: update entry for atmel_serial driver
serial: pl011: add console matching function
ARM64: ACPI: enable ACPI_SPCR_TABLE
ACPI: parse SPCR and enable matching console
of/serial: move earlycon early_param handling to serial
Revert "drivers/tty: Explicitly pass current to show_stack"
tty: amba-pl011: Don't complain on -EPROBE_DEFER when no irq
nios2: dts: 10m50: Add tx-threshold parameter
serial: 8250: Set Altera 16550 TX FIFO Threshold
serial: 8250: of: Load TX FIFO Threshold from DT
Documentation: dt: serial: Add TX FIFO threshold parameter
drivers/tty: Explicitly pass current to show_stack
serial: imx: Fix DCD reading
serial: stm32: mark symbols static where possible
serial: xuartps: Add some register initialisation to cdns_early_console_setup()
serial: xuartps: Removed unwanted checks while reading the error conditions
serial: xuartps: Rewrite the interrupt handling logic
serial: stm32: use mapbase instead of membase for DMA
tty/serial: atmel: fix fractional baud rate computation
...
Pull char/misc driver updates from Greg KH:
"Here's the "big" char and misc driver update for 4.9-rc1.
Lots of little things here, all over the driver tree for subsystems
that flow through me. Nothing major that I can discern, full details
are in the shortlog.
All have been in the linux-next tree with no reported issues"
* tag 'char-misc-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (144 commits)
drivers/misc/hpilo: Changes to support new security states in iLO5 FW
at25: fix debug and error messaging
misc/genwqe: ensure zero initialization
vme: fake: remove unexpected unlock in fake_master_set()
vme: fake: mark symbols static where possible
spmi: pmic-arb: Return an error code if sanity check fails
Drivers: hv: get rid of id in struct vmbus_channel
Drivers: hv: make VMBus bus ids persistent
mcb: Add a dma_device to mcb_device
mcb: Enable PCI bus mastering by default
mei: stop the stall timer worker if not needed
clk: probe common clock drivers earlier
vme: fake: fix build for 64-bit dma_addr_t
ttyprintk: Neaten and simplify printing
mei: me: add kaby point device ids
coresight: tmc: mark symbols static where possible
coresight: perf: deal with error condition properly
Drivers: hv: hv_util: Avoid dynamic allocation in time synch
fpga manager: Add hardware dependency to Zynq driver
Drivers: hv: utils: Support TimeSync version 4.0 protocol samples.
...
* device-properties:
serial: 8250_dw: Add quirk for APM X-Gene SoC
ACPI / LPSS: Provide build-in properties of the UART
ACPI / APD: Provide build-in properties of the UART
driver core: Don't leak secondary fwnode on device removal
This patch adds function pl011_console_match() that implements
method match of struct console. It allows to match consoles against
data specified in a string, for example taken from command line or
compiled by ACPI SPCR table handler.
Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Tested-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Altera 16550 soft IP UART requires 2 additional registers for
TX FIFO threshold support. These 2 registers enable the TX FIFO
Low Watermark and set the TX FIFO Low Watermark.
Set the TX FIFO threshold to the FIFO size - tx_loadsz.
Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Initialize the tx_loadsz parameter from passed in devicetree
tx-threshold parameter.
The tx_loadsz is calculated as the number of bytes to fill FIFO
when tx-threshold is triggered.
Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We get 2 warnings when building kernel with W=1:
drivers/tty/serial/stm32-usart.c:63:5: warning: no previous prototype for 'stm32_pending_rx' [-Wmissing-prototypes]
drivers/tty/serial/stm32-usart.c:88:15: warning: no previous prototype for 'stm32_get_char' [-Wmissing-prototypes]
In fact, these two functions are only used in the file in which they are
declared and don't need a declaration, but can be made static.
So this patch marks these functions with 'static'.
Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add initialisation of control register and baud rate to
cdns_early_console_setup(), required when running kernel standalone
without a boot loader. Baud rate is only initialised when specified in
earlycon command-line option, otherwise it is assumed this has been
set by a boot loader. Updated Documentation/kernel-parameters.txt
accordingly.
Signed-off-by: Scott Telford <stelford@cadence.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The existing interrupt handling logic has following issues.
- Upon a parity error with default configuration, the control
never comes out of the ISR thereby hanging Linux.
- The error handling logic around framing and parity error are buggy.
There are chances that the errors will never be captured.
This patch ensures that the status registers are cleared on all cases so
that a hang situation never arises.
Signed-off-by: Anirudha Sarangi <anirudh@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
[stelford@cadence.com: cherry picked from
https://github.com/Xilinx/linux-xlnx commit
ac297e20d399850d7a8e373b6eccf2e183c15165 with manual conflict resolution]
Signed-off-by: Scott Telford <stelford@cadence.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Building this driver with a 64-bit dma_addr_t type results in
a compiler warning:
drivers/tty/serial/stm32-usart.c: In function 'stm32_of_dma_rx_probe':
drivers/tty/serial/stm32-usart.c:746:20: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
drivers/tty/serial/stm32-usart.c: In function 'stm32_of_dma_tx_probe':
drivers/tty/serial/stm32-usart.c:818:20: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
While the type conversion here is harmless, this hints at a different
problem: we pass an __iomem pointer into a DMA engine, which expects
a phys_addr_t. This happens to work because stm32 has no MMU and
ioremap() is an identity mapping here, but it's still an incorrect
API use. Using dma_addr_t is doubly wrong here, because that would
be the result of dma_map_single() rather than the physical address.
Using the mapbase instead fixes multiple issues:
- the warning is gone
- we don't go through ioremap in error
- the cast is gone, making it use the correct resource_size_t/phys_addr_t
type in the process.
Fixes: 3489187204 ("serial: stm32: adding dma support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The problem with previous code was it rounded values in wrong
place and produced wrong baud rate in some cases.
Signed-off-by: Alexey Starikovskiy <aystarik@gmail.com>
[nicolas.ferre@atmel.com: port to newer kernel and add commit log]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The patch makes changes not to enable parity error interrupt.
With the current implementation, each parity error results in
two distinct interrupts (almost always). The first one is normal
parity error interrupt with no data in the fifo and the second one
is a proper Rx interrupt with the received data in the fifo. By
disabling parity error interrupt we still ensure handling of
parity errors as for the Rx fifo interrupt the parity error still
shows up in the interrupt status register. Considering the fact
that the by default INPCK and IGNPAR are not set, this is the
optimal implementation for parity error handling.
Signed-off-by: Anirudha Sarangi <anirudh@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
[stelford@cadence.com: cherry picked from
https://github.com/Xilinx/linux-xlnx commit
bf9f610b445e2c9ed33c41e1e0e30b43be4e1f97 with manual conflict
resolution]
Signed-off-by: Scott Telford <stelford@cadence.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
