While closing, new rx data may be received after the input buffers
have been flushed but before stop_rx() halts receiving [1]. The
new data might not be processed by flush_to_ldisc() until after
uart_shutdown() and normal input processing is re-enabled (ie.,
tty->closing = 0). The race is outlined below:
CPU 0 | CPU 1
|
uart_close() |
tty_port_close_start() |
tty->closing = 1 |
tty_ldisc_flush() |
| => IRQ
| while (LSR & data ready)
| uart_insert_char()
| tty_flip_buffer_push()
| <= EOI
stop_rx() | .
uart_shutdown() | .
free xmit.buf | .
tty_port_tty_set(NULL) | .
tty->closing = 0 | .
| flush_to_ldisc()
| n_tty_receive_buf_common()
| __receive_buf()
| ...
| commit_echoes()
| uart_flush_chars()
| __uart_start()
| ** OOPS on port.tty deref **
tty_ldisc_flush() |
Input processing must be prevented from echoing (tty->closing = 1)
until _after_ the input buffers have been flushed again at the end
of uart_close().
[1] In fact, some input may actually be buffered _after_ stop_rx()
since the rx interrupt may have already triggered but not yet been
handled when stop_rx() disables rx interrupts.
Fixes: 2e75891083 ("serial: core: Flush ldisc after dropping port
mutex in uart_close()")
Reported-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 068500e08d.
According to some tests, SDMA support is broken at least for i.MX6 without
HW flow control. Different forms of data-corruption appear either with
the ROM firmware for the SDMA controller as well as when loading Freescale
provided SDMA firmware versions 1.1 or 3.1.
Signed-off-by: David Jander <david@protonic.nl>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Calls to regmap_raw_read/write needed register rewrite in a
similar way as function calls to regmap_read/write already had.
This enables reading/writing the serial datastream to the device.
Signed-off-by: Bo Svangård <bo.svangard@embeddedart.se>
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When I2C=m and SPI=y or-ing them will produce =y while
what we need is the lower bound, i.e. =m. Fortunately
SPI is a boolean so we need to handle only one special
case.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In probe, we use dev_id as array index of etraxfs_uart_ports and store the
index in port->line. So etraxfs_uart_ports[port->line] should be released
when unload the module.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Niklas Cassel <nks@flawful.org>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Value returned by devm_ioremap_resource() was checked for non-NULL but
devm_ioremap_resource() returns IOMEM_ERR_PTR, not NULL. In case of
error this could lead to dereference of ERR_PTR.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Cc: <stable@vger.kernel.org>
Fixes: 3873e2d7f6 ("drivers: PL011: refactor pl011_probe()")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull ARM SoC late fixes and dependencies from Kevin Hilman:
"This is a collection of a few late fixes and other misc stuff that had
dependencies on things being merged from other trees.
Other than the fixes, the primary feature being added is the
conversion of some OMAP drivers to the new generic wakeirq interface"
* tag 'armsoc-late' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: multi_v7_defconfig: Enable BRCMNAND driver
ARM: BCM: Do not select CONFIG_MTD_NAND_BRCMNAND
ARM: at91/dt: update udc compatible strings
ARM: at91/dt: trivial: fix USB udc compatible string
arm64: dts: Add APM X-Gene standby GPIO controller DTS entries
soc: qcom: spm: Fix idle on THUMB2 kernels
ARM: dove: fix legacy dove IRQ numbers
ARM: mvebu: fix suspend to RAM on big-endian configurations
ARM: mvebu: adjust Armada XP DT spi muxing after pinctrl function rename
serial: 8250_omap: Move wake-up interrupt to generic wakeirq
serial: omap: Switch wake-up interrupt to generic wakeirq
mmc: omap_hsmmc: Change wake-up interrupt to use generic wakeirq
Pull MIPS updates from Ralf Baechle:
- Improvements to the tlb_dump code
- KVM fixes
- Add support for appended DTB
- Minor improvements to the R12000 support
- Minor improvements to the R12000 support
- Various platform improvments for BCM47xx
- The usual pile of minor cleanups
- A number of BPF fixes and improvments
- Some improvments to the support for R3000 and DECstations
- Some improvments to the ATH79 platform support
- A major patchset for the JZ4740 SOC adding support for the CI20 platform
- Add support for the Pistachio SOC
- Minor BMIPS/BCM63xx platform support improvments.
- Avoid "SYNC 0" as memory barrier when unlocking spinlocks
- Add support for the XWR-1750 board.
- Paul's __cpuinit/__cpuinitdata cleanups.
- New Malta CPU board support large memory so enable ZONE_DMA32.
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (131 commits)
MIPS: spinlock: Adjust arch_spin_lock back-off time
MIPS: asmmacro: Ensure 64-bit FP registers are used with MSA
MIPS: BCM47xx: Simplify handling SPROM revisions
MIPS: Cobalt Don't use module_init in non-modular MTD registration.
MIPS: BCM47xx: Move NVRAM driver to the drivers/firmware/
MIPS: use for_each_sg()
MIPS: BCM47xx: Don't select BCMA_HOST_PCI
MIPS: BCM47xx: Add helper variable for storing NVRAM length
MIPS: IRQ/IP27: Move IRQ allocation API to platform code.
MIPS: Replace smp_mb with release barrier function in unlocks.
MIPS: i8259: DT support
MIPS: Malta: Basic DT plumbing
MIPS: include errno.h for ENODEV in mips-cm.h
MIPS: Define GCR_GIC_STATUS register fields
MIPS: BPF: Introduce BPF ASM helpers
MIPS: BPF: Use BPF register names to describe the ABI
MIPS: BPF: Move register definition to the BPF header
MIPS: net: BPF: Replace RSIZE with SZREG
MIPS: BPF: Free up some callee-saved registers
MIPS: Xtalk: Update xwidget.h with known Xtalk device numbers
...
Pull tty/serial driver updates from Greg KH:
"Here's the tty and serial driver patches for 4.2-rc1.
A number of individual driver updates, some code cleanups, and other
minor things, full details in the shortlog.
All have been in linux-next for a while with no reported issues"
* tag 'tty-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (152 commits)
Doc: serial-rs485.txt: update RS485 driver interface
Doc: tty.txt: remove mention of the BKL
MAINTAINERS: tty: add serial docs directory
serial: sprd: check for NULL after calling devm_clk_get
serial: 8250_pci: Correct uartclk for xr17v35x expansion chips
serial: 8250_pci: Add support for 12 port Exar boards
serial: 8250_uniphier: add bindings document for UniPhier UART
serial: core: cleanup in uart_get_baud_rate()
serial: stm32-usart: Add STM32 USART Driver
tty/serial: kill off set_irq_flags usage
tty: move linux/gsmmux.h to uapi
doc: dt: add documentation for nxp,lpc1850-uart
serial: 8250: add LPC18xx/43xx UART driver
serial: 8250_uniphier: add UniPhier serial driver
serial: 8250_dw: support ACPI platforms with integrated DMA engine
serial: of_serial: check the return value of clk_prepare_enable()
serial: of_serial: use devm_clk_get() instead of clk_get()
serial: earlycon: Add support for big-endian MMIO accesses
serial: sirf: use hrtimer for data rx
serial: sirf: correct the fifo empty_bit
...
Pull Renesas H8/300 architecture re-introduction from Yoshinori Sato.
We dropped arch/h8300 two years ago as stale and old, this is a new and
more modern rewritten arch support for the same architecture.
* tag 'for-4.2' of git://git.sourceforge.jp/gitroot/uclinux-h8/linux: (27 commits)
h8300: fix typo.
h8300: Always build dtb
h8300: Remove ARCH_WANT_IPC_PARSE_VERSION
sh-sci: Get register size from platform device
clk: h8300: fix error handling in h8s2678_pll_clk_setup()
h8300: Symbol name fix
h8300: devicetree source
h8300: configs
h8300: IRQ chip driver
h8300: clocksource
h8300: clock driver
h8300: Build scripts
h8300: library functions
h8300: Memory management
h8300: miscellaneous functions
h8300: process helpers
h8300: compressed image support
h8300: Low level entry
h8300: kernel startup
h8300: Interrupt and exceptions
...
Pull gpio updates from Linus Walleij:
"This is the big bulk of GPIO changes queued for the v4.2 kernel
series:
- a big set of cleanups to the aged sysfs interface from Johan
Hovold. To get these in, v4.1-rc3 was merged into the tree as the
first patch in that series had to go into stable. This makes the
locking much more fine-grained (get rid of the "big GPIO lock(s)"
and store states in the GPIO descriptors.
- rename gpiod_[g|s]et_array() to gpiod_[g|s]et_array_value() to
avoid confusions.
- New drivers for:
* NXP LPC18xx (currently LPC1850)
* NetLogic XLP
* Broadcom STB SoC's
* Axis ETRAXFS
* Zynq Ultrascale+ (subdriver)
- ACPI:
* make it possible to retrieve GpioInt resources from a GPIO
device using acpi_dev_gpio_irq_get()
* merge some dependent I2C changes exploiting this.
* support the ARM X-Gene GPIO standby driver.
- make it possible for the generic GPIO driver to read back the value
set registers to reflect current status.
- loads of OMAP IRQ handling fixes.
- incremental improvements to Kona, max732x, OMAP, MXC, RCAR,
PCA953x, STP-XWAY, PCF857x, Crystalcove, TB10x.
- janitorial (constification, checkpatch cleanups)"
* tag 'gpio-v4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (71 commits)
gpio: Fix checkpatch.pl issues
gpio: pcf857x: handle only enabled irqs
gpio / ACPI: Return -EPROBE_DEFER if the gpiochip was not found
GPIO / ACPI: export acpi_gpiochip_request(free)_interrupts for module use
gpio: improve error reporting on own descriptors
gpio: promote own request failure to pr_err()
gpio: Added support to Zynq Ultrascale+ MPSoC
gpio: add ETRAXFS GPIO driver
fix documentation after renaming gpiod_set_array to gpiod_set_array_value
gpio: Add GPIO support for Broadcom STB SoCs
gpio: xgene: add ACPI support for APM X-Gene GPIO standby driver
gpio: tb10x: Drop unneeded free_irq() call
gpio: crystalcove: set IRQCHIP_SKIP_SET_WAKE for the irqchip
gpio: stp-xway: Use the of_property_read_u32 helper
gpio: pcf857x: Check for irq_set_irq_wake() failures
gpio-stp-xway: Fix enabling the highest bit of the PHY LEDs
gpio: Prevent an integer overflow in the pca953x driver
gpio: omap: rework omap_gpio_irq_startup to handle current pin state properly
gpio: omap: rework omap_gpio_request to touch only gpio specific registers
gpio: omap: rework omap_x_irq_shutdown to touch only irqs specific registers
...
In platforms which does not use CLK framework (HAVE_CLK not set), the
clk_* functions return NULL instead of an error. This patch handles that
scenario.
Signed-off-by: Fernando Guzman Lugo <fernando.guzman.lugo@intel.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The internal clock of the master chip, which is usually 125MHz, is only half
(62.5MHz) for the slave chips. So we have to adjust the uartclk for all the
slave ports. Therefor we add a new function to determine if a slave chip is
present and update pci_xr17v35x_setup accordingly.
Signed-off-by: Soeren Grunewald <soeren.grunewald@desy.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Exar XR17V358 can also be combined with a XR17V354 chip to act as a
single 12 port chip. This works the same way as the combining two XR17V358
chips. But the reported device id then is 0x4358.
Signed-off-by: Soeren Grunewald <soeren.grunewald@desy.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We can now use generic wakeirq handling and remove the custom handling
for the wake-up interrupts.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
We can now use generic wakeirq handling and remove the custom handling
for the wake-up interrupts.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
set_irq_flags is ARM specific with custom flags which have genirq
equivalents. Convert drivers to use the genirq interfaces directly, so we
can kill off set_irq_flags. The translation of flags is as follows:
IRQF_VALID -> !IRQ_NOREQUEST
IRQF_PROBE -> !IRQ_NOPROBE
IRQF_NOAUTOEN -> IRQ_NOAUTOEN
For IRQs managed by an irqdomain, the irqdomain core code handles clearing
and setting IRQ_NOREQUEST already, so there is no need to do this in
.map() functions and we can simply remove the set_irq_flags calls. Some
users also set IRQ_NOPROBE and this has been maintained although it is not
clear that is really needed. There appears to be a great deal of blind
copy and paste of this code.
Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Barry Song <baohua@kernel.org>
Cc: linux-serial@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This fixes up a merge issue with the amba-pl011.c driver, and we want
the fixes in this branch as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There have been concerns that the function names gpiod_set_array() and
gpiod_get_array() might be confusing to users. One might expect
gpiod_get_array() to return array values, while it is actually the array
counterpart of gpiod_get(). To be consistent with the single descriptor API
we could rename gpiod_set_array() to gpiod_set_array_value(). This makes
some function names a bit lengthy: gpiod_set_raw_array_value_cansleep().
Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The currently in-use port->startup and port->shutdown are "okay". The
startup part for instance does the tiny omap extra part and invokes
serial8250_do_startup() for the remaining pieces. The workflow in
serial8250_do_startup() is okay except for the part where UART_RX is
read without a check if there is something to read. I tried to
workaround it in commit 0aa525d118 ("tty: serial: 8250_core: read only
RX if there is something in the FIFO") but then reverted it later in
commit ca8bb4aefb ("serial: 8250: Revert "tty: serial: 8250_core: read
only RX if there is something in the FIFO"").
This is the second attempt to get it to work on older OMAPs without
breaking other chips this time
Peter Hurley suggested to pull in the few needed lines from
serial8250_do_startup() and drop everything else that is not required
including making it simpler like using just request_irq() instead the
chain handler like it is doing now.
So lets try that.
Fixes: ca8bb4aefb ("serial: 8250: Revert "tty: serial: 8250_core:
read only RX if there is something in the FIFO"")
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
