This reverts commit 2e9fe53910.
Reading LSR unconditionally but processing the error flags only if
UART_IIR_RDI bit was set before in IIR may lead to a loss of transmission
error information on UARTs where the transmission error flags are cleared
by a read of LSR. Information are lost in case an error is detected right
before the read of LSR while processing e.g. an UART_IIR_THRI interrupt.
Signed-off-by: Oliver Barta <o.barta89@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Fixes: 2e9fe53910 ("serial: 8250: Don't service RX FIFO if interrupts are disabled")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch permits the usage for GPIOs to control
the CTS/RTS/DTR/DSR/DCD/RI signals.
Changed by Stefan:
Only call mctrl_gpio_init(), if the device has no ACPI companion device
to not break existing ACPI based systems. Also only use the mctrl_gpio_
functions when "gpios" is available.
Use MSR / MCR <-> TIOCM wrapper functions.
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Yegor Yefremov <yegorslists@googlemail.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Giulio Benetti <giulio.benetti@micronovasrl.com>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds wrapper functions to convert MSR <-> TIOCM and also
MCR <-> TIOCM. These functions are used now in serial8250_do_set_mctrl()
and serial8250_do_get_mctrl().
Signed-off-by: Stefan Roese <sr@denx.de>
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Giulio Benetti <giulio.benetti@micronovasrl.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Factor out similar code pieces that set or clear UART_IER_THRI bit to
serial8250_{set,clear}_THRI() helpers.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Pericom chips can achieve additional baud rates by programming the
sample clock register. The baud rates can be described as
921600 * 16 / (16 - scr) for scr values 5 to 15. The divisor is set to 1
for these baud rates.
Adds new quirk for Pericom chips other than the four port chips to use
the
Signed-off-by: Jay Dolan <jay.dolan@accesio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Interrupt handler checked THRE bit (transmitter holding register
empty) in LSR to detect if TX fifo is empty.
In case when there is only receive interrupts the TX handling
got called because THRE bit in LSR is set when there is no
transmission (FIFO empty). TX handling caused TX stop, which in
RS-485 half-duplex mode actually resets receiver FIFO. This is not
desired during reception because of possible data loss.
The fix is to check if THRI is set in IER in addition of the TX
fifo status. THRI in IER is set when TX is started and cleared
when TX is stopped.
This ensures that TX handling is only called when there is really
transmission on going and an interrupt for THRE and not when there
are only RX interrupts.
Signed-off-by: Kimmo Rautkoski <ext-kimmo.rautkoski@vaisala.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Deferred probe is an expected return value for clk_get() on many
platforms. The driver deals with it properly, so there's no need
to output a warning that may potentially confuse users.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In order to support Rx in-band wakeup, we need to enable irq wake on an
edge sensitive interrupt of Rx pin before suspend and disable it when
resuming.
This interrupt is used only as wake source to resume the system when
suspended. Note that the sent character will be lost as the controller is
actually suspended.
We use this to support wakeup on bluetooth. Bluetooth will repeatedly send
0xFD to wakeup host. Once host detects Rx falling, an interrupt is
triggered, and the system leaves sleep state. Then, the bluetooth driver
will send 0xFC to bluetooth and bluetooth can start to send normal HCI
packets.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The dev_dbg statement should print the value of uart.port.mapbase instead
of its address. Besides that, uart.port.irq and uart.port.iotype are all
unsigned types, so using %u is more appropriate.
Signed-off-by: Hao Lee <haolee.swjtu@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use of_device_get_match_data() to simplify the code a bit.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- Updates to stm32 dma residue calculations
- Interleave dma capability to axi-dmac and
support for ZynqMP arch
- Rework of channel assignment for rcar dma
- Debugfs for pl330 driver
- Support for Tegra186/Tegra194, refactoring for new chips
and support for pause/resume
- Updates to axi-dmac, bcm2835, fsl-edma, idma64, imx-sdma,
rcar-dmac, stm32-dma etc
- dev_get_drvdata() updates on few drivers
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Merge tag 'dmaengine-5.2-rc1' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine updates from Vinod Koul:
- Updates to stm32 dma residue calculations
- Interleave dma capability to axi-dmac and support for ZynqMP arch
- Rework of channel assignment for rcar dma
- Debugfs for pl330 driver
- Support for Tegra186/Tegra194, refactoring for new chips and support
for pause/resume
- Updates to axi-dmac, bcm2835, fsl-edma, idma64, imx-sdma, rcar-dmac,
stm32-dma etc
- dev_get_drvdata() updates on few drivers
* tag 'dmaengine-5.2-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (34 commits)
dmaengine: tegra210-adma: restore channel status
dmaengine: tegra210-dma: free dma controller in remove()
dmaengine: tegra210-adma: add pause/resume support
dmaengine: tegra210-adma: add support for Tegra186/Tegra194
Documentation: DT: Add compatibility binding for Tegra186
dmaengine: tegra210-adma: prepare for supporting newer Tegra chips
dmaengine: at_xdmac: remove a stray bottom half unlock
dmaengine: fsl-edma: Adjust indentation
dmaengine: fsl-edma: Fix typo in Vybrid name
dmaengine: stm32-dma: fix residue calculation in stm32-dma
dmaengine: nbpfaxi: Use dev_get_drvdata()
dmaengine: bcm-sba-raid: Use dev_get_drvdata()
dmaengine: stm32-dma: Fix unsigned variable compared with zero
dmaengine: stm32-dma: use platform_get_irq()
dmaengine: rcar-dmac: Update copyright information
dmaengine: imx-sdma: Only check ratio on parts that support 1:1
dmaengine: xgene-dma: fix spelling mistake "descripto" -> "descriptor"
dmaengine: idma64: Move driver name to the header
dmaengine: bcm2835: Drop duplicate capability setting.
dmaengine: pl330: _stop: clear interrupt status
...
Add SW and HW follow control function.
Signed-off-by: Long Cheng <long.cheng@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since there are more IOT2040 variants with identical hardware but
different asset tags, the asset tag matching should be adjusted to
support them.
As only the IOT2040 variants have the Exar chip on board, matching on
their board name is enough. In the future there will be no other devices
with the "SIMATIC IOT2000" DMI board name but different hardware.
Signed-off-by: Su Bao Cheng <baocheng.su@siemens.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There were a few straggling files under drivers/tty/ that did not have
any SPDX identifier either because they entered the tree recently, or
they somehow missed the mass-tagging of commit b24413180f ("License
cleanup: add SPDX GPL-2.0 license identifier to files with no license")
This commit follows the same rule as b24413180f ("License cleanup: add
SPDX GPL-2.0 license identifier to files with no license") where files
without any specified license in them fall under GPL-2.0 as the correct
license for the individual file. Add that identifier to these remaining
files so that we don't have to guess at the license of them in the
future.
Cc: Jiri Slaby <jslaby@suse.com>
Cc: "David S. Miller" <davem@davemloft.net>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There were a few Kconfig and Makefiles under drivers/tty/ that were
missing a SPDX identifier. Fix that up so that automated tools can
properly classify all kernel source files.
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix sparse warning:
drivers/tty/serial/8250/8250_fintek.c:306:6: warning:
symbol 'fintek_8250_set_termios' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Intel IOMMU, when enabled, tries to find the domain of the device,
assuming it's a PCI one, during DMA operations, such as mapping or
unmapping. Since we are splitting the actual PCI device to couple of
children via MFD framework (see drivers/mfd/intel-lpss.c for details),
the DMA device appears to be a platform one, and thus not an actual one
that performs DMA. In a such situation IOMMU can't find or allocate
a proper domain for its operations. As a result, all DMA operations are
failed.
In order to fix this, supply parent of the platform device
to the DMA engine framework and fix filter functions accordingly.
We may rely on the fact that parent is a real PCI device, because no
other configuration is present in the wild.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [for tty parts]
Signed-off-by: Vinod Koul <vkoul@kernel.org>
- dmatest updates for modularizing common struct and code
- remove SG support for VDMA xilinx IP and updates to driver
- Update to dw driver to support Intel iDMA controllers
multi-block support
- tegra updates for proper reporting of residue
- Add Snow Ridge ioatdma device id and support for IOATDMA v3.4
- struct_size() usage and useless LIST_HEAD cleanups in subsystem.
- qDMA controller driver for Layerscape SoCs
- stm32-dma PM Runtime support
- And usual updates to imx-sdma, sprd, Documentation, fsl-edma,
bcm2835, qcom_hidma etc
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Merge tag 'dmaengine-5.1-rc1' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine updates from Vinod Koul:
- dmatest updates for modularizing common struct and code
- remove SG support for VDMA xilinx IP and updates to driver
- Update to dw driver to support Intel iDMA controllers multi-block
support
- tegra updates for proper reporting of residue
- Add Snow Ridge ioatdma device id and support for IOATDMA v3.4
- struct_size() usage and useless LIST_HEAD cleanups in subsystem.
- qDMA controller driver for Layerscape SoCs
- stm32-dma PM Runtime support
- And usual updates to imx-sdma, sprd, Documentation, fsl-edma,
bcm2835, qcom_hidma etc
* tag 'dmaengine-5.1-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (81 commits)
dmaengine: imx-sdma: fix consistent dma test failures
dmaengine: imx-sdma: add a test for imx8mq multi sdma devices
dmaengine: imx-sdma: add clock ratio 1:1 check
dmaengine: dmatest: move test data alloc & free into functions
dmaengine: dmatest: add short-hand `buf_size` var in dmatest_func()
dmaengine: dmatest: wrap src & dst data into a struct
dmaengine: ioatdma: support latency tolerance report (LTR) for v3.4
dmaengine: ioatdma: add descriptor pre-fetch support for v3.4
dmaengine: ioatdma: disable DCA enabling on IOATDMA v3.4
dmaengine: ioatdma: Add Snow Ridge ioatdma device id
dmaengine: sprd: Change channel id to slave id for DMA cell specifier
dt-bindings: dmaengine: sprd: Change channel id to slave id for DMA cell specifier
dmaengine: mv_xor: Use correct device for DMA API
Documentation :dmaengine: clarify DMA desc. pointer after submission
Documentation: dmaengine: fix dmatest.rst warning
dmaengine: k3dma: Add support for dma-channel-mask
dmaengine: k3dma: Delete axi_config
dmaengine: k3dma: Upgrade k3dma driver to support hisi_asp_dma hardware
Documentation: bindings: dma: Add binding for dma-channel-mask
Documentation: bindings: k3dma: Extend the k3dma driver binding to support hisi-asp
...
There are two other drivers that bind to mrvl,mmp-uart and both of them
assume register shift of 2 bits. There are device trees that lack the
property and rely on that assumption.
If this driver wins the race to bind to those devices, it should behave
the same as the older deprecated driver.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Like the other OF-enabled drivers, use the port number from the firmware if
the devicetree specifies an alias:
aliases {
...
serial2 = &uart2; /* Should be ttyS2 */
}
This is how the deprecated pxa.c driver behaved, switching to 8250_pxa
messes up the numbering.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The four port Pericom chips have the fourth port at the wrong address.
Make use of quirk to fix it.
Fixes: c8d192428f ("serial: 8250: added acces i/o products quad and octal serial cards")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jay Dolan <jay.dolan@accesio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Have the correct number of ports created for ACCES serial cards. Two port
cards show up as four ports, and four port cards show up as eight.
Fixes: c8d192428f ("serial: 8250: added acces i/o products quad and octal serial cards")
Signed-off-by: Jay Dolan <jay.dolan@accesio.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial_pci_is_blacklisted() is very similar to pci_match_id() implementation.
Replace it with the latter.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As has been reported the National Instruments serial cards have broken
PCI class.
The commit 7d8905d064
("serial: 8250_pci: Enable device after we check black list")
made the PCI class check mandatory for the case when device is listed in
a quirk list.
Make PCI class test non fatal to allow broken card be enumerated.
Fixes: 7d8905d064 ("serial: 8250_pci: Enable device after we check black list")
Cc: stable <stable@vger.kernel.org>
Reported-by: Guan Yung Tseng <guan.yung.tseng@ni.com>
Tested-by: Guan Yung Tseng <guan.yung.tseng@ni.com>
Tested-by: KHUENY.Gerhard <Gerhard.KHUENY@bachmann.info>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a potential NULL pointer dereference in case devm_kzalloc()
fails and returns NULL.
Fix this by adding a NULL check on data->dma
This bug was detected with the help of Coccinelle.
Fixes: 85b5c1dd04 ("serial: 8250-mtk: add uart DMA support")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for probing the 8250_ingenic driver on the
X1000 Soc from Ingenic.
Signed-off-by: Zhou Yanjie <zhouyanjie@zoho.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds support for device tree probing for the Intel
Xscale 8250 variant needed to support device tree on
the Intel IXP4xx platforms.
Cc: devicetree@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The initialization code of interrupt backoff work might reference NULL
pointer and cause the following crash, if no port was found.
[ 10.017727] CPU 0 Unable to handle kernel paging request at virtual address 000001b0, epc == 807088e0, ra == 8070863c
---- snip ----
[ 11.704470] [<807088e0>] serial8250_register_8250_port+0x318/0x4ac
[ 11.747251] [<80708d74>] serial8250_probe+0x148/0x1c0
[ 11.789301] [<80728450>] platform_drv_probe+0x40/0x94
[ 11.830515] [<807264f8>] really_probe+0xf8/0x318
[ 11.870876] [<80726b7c>] __driver_attach+0x110/0x12c
[ 11.910960] [<80724374>] bus_for_each_dev+0x78/0xcc
[ 11.951134] [<80725958>] bus_add_driver+0x200/0x234
[ 11.989756] [<807273d8>] driver_register+0x84/0x148
[ 12.029832] [<80d72f84>] serial8250_init+0x138/0x198
[ 12.070447] [<80100e6c>] do_one_initcall+0x5c/0x2a0
[ 12.110104] [<80d3a208>] kernel_init_freeable+0x370/0x484
[ 12.150722] [<80a49420>] kernel_init+0x10/0xf8
[ 12.191517] [<8010756c>] ret_from_kernel_thread+0x14/0x1c
This patch makes sure the initialization code can be reached only if a port
is found.
Fixes: 6d7f677a2a ("serial: 8250: Rate limit serial port rx interrupts during input overruns")
Signed-off-by: He Zhe <zhe.he@windriver.com>
Reviewed-by: Darwin Dingel <darwin.dingel@alliedtelesis.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8250_omap driver uses clock-frequency DT property to obtain functional
clk frequency. This is not ideal as users need to calculate functional
clk frequency offline and populate it in DT.
Therefore add support to obtain functional clock frequency using clk
APIs when clock-frequency DT property is not defined.
Suggested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8250_omap is DT only driver so dev->of_node always exists. Drop check
for existence of valid dev->of_node to simplify omap8250_probe().
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit a9ddb575d6
("dmaengine: dw_dmac: Enhance device tree support")
introduces is_private property in uncertain understanding what does it mean.
First of all, documentation defines DMA_PRIVATE capability as
Documentation/crypto/async-tx-api.txt:
The DMA_PRIVATE capability flag is used to tag dma devices that should not be
used by the general-purpose allocator. It can be set at initialization time
if it is known that a channel will always be private. Alternatively,
it is set when dma_request_channel() finds an unused "public" channel.
A couple caveats to note when implementing a driver and consumer:
1/ Once a channel has been privately allocated it will no longer be
considered by the general-purpose allocator even after a call to
dma_release_channel().
2/ Since capabilities are specified at the device level a dma_device with
multiple channels will either have all channels public, or all channels
private.
Documentation/driver-api/dmaengine/provider.rst:
- DMA_PRIVATE
The devices only supports slave transfers, and as such isn't available
for async transfers.
The capability had been introduced by the commit 59b5ec2144
("dmaengine: introduce dma_request_channel and private channels")
and some code didn't changed from that times ever.
Taking into consideration above and the fact that on all known platforms
Synopsys DesignWare DMA engine is attached to serve slave transfers,
the DMA_PRIVATE capability must be enabled for this device unconditionally.
Otherwise, as rightfully noticed in drivers/dma/at_xdmac.c:
/*
* Without DMA_PRIVATE the driver is not able to allocate more than
* one channel, second allocation fails in private_candidate.
*/
because of of a caveats mentioned in above documentation excerpts.
So, remove conditional around DMA_PRIVATE followed by removal leftovers.
If someone wonders, DMA_PRIVATE can be not used if and only if the all channels
of the DMA controller are supposed to serve memory-to-memory like operations.
For example, EP93xx has two controllers, one of which can only perform
memory-to-memory transfers
Note, this change doesn't affect dmatest to be able to test such controllers.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> (maintainer:SERIAL DRIVERS)
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Here is the large TTY/Serial driver set of patches for 4.21-rc1.
A number of small serial driver changes along with some good tty core
fixes for long-reported issues with locking. There is also a new
console font added to the tree, for high-res screens, so that should be
helpful for many.
The last patch in the series is a revert of an older one in the tree, it
came late but it resolves a reported issue that linux-next was having
for some people.
Full details are in the shortlog, and all of these, with the exception
of the revert, have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here is the large TTY/Serial driver set of patches for 4.21-rc1.
A number of small serial driver changes along with some good tty core
fixes for long-reported issues with locking. There is also a new
console font added to the tree, for high-res screens, so that should
be helpful for many.
The last patch in the series is a revert of an older one in the tree,
it came late but it resolves a reported issue that linux-next was
having for some people.
Full details are in the shortlog, and all of these, with the exception
of the revert, have been in linux-next for a while with no reported
issues"
* tag 'tty-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (85 commits)
Revert "serial: 8250: Default SERIAL_OF_PLATFORM to SERIAL_8250"
serial: sccnxp: Allow to use non-standard baud rates
serial: sccnxp: Adds a delay between sequential read/write cycles
tty: serial: qcom_geni_serial: Fix UART hang
tty: serial: qcom_geni_serial: Fix wrap around of TX buffer
serial: max310x: Fix tx_empty() callback
dt-bindings: serial: sh-sci: Document r8a774c0 bindings
dt-bindings: serial: sh-sci: Document r8a774a1 bindings
Fonts: New Terminus large console font
dt-bindings: serial: lpuart: add imx8qxp compatible string
serial: uartps: Fix interrupt mask issue to handle the RX interrupts properly
serial: uartps: Fix error path when alloc failed
serial: uartps: Check if the device is a console
serial: uartps: Add the device_init_wakeup
tty: serial: samsung: Increase maximum baudrate
tty: serial: samsung: Properly set flags in autoCTS mode
tty: Use of_node_name_{eq,prefix} for node name comparisons
tty/serial: do not free trasnmit buffer page under port lock
serial: 8250: Rate limit serial port rx interrupts during input overruns
dt-bindings: serial: 8250: Add rate limit for serial port input overruns
...
This reverts commit 6d11023c34.
It causes issues with Guenter's test systems and since there seems to
not be any agreement about _why_ this is a problem, but reverting it
fixes things, let's revert until the root cause is found.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit f6aa5beb45 ("serial: 8250: Fix clearing FIFOs in RS485 mode
again") makes a change to FIFO clearing code which its commit message
suggests was intended to be specific to use with RS485 mode, however:
1) The change made does not just affect __do_stop_tx_rs485(), it also
affects other uses of serial8250_clear_fifos() including paths for
starting up, shutting down or auto-configuring a port regardless of
whether it's an RS485 port or not.
2) It makes the assumption that resetting the FIFOs is a no-op when
FIFOs are disabled, and as such it checks for this case & explicitly
avoids setting the FIFO reset bits when the FIFO enable bit is
clear. A reading of the PC16550D manual would suggest that this is
OK since the FIFO should automatically be reset if it is later
enabled, but we support many 16550-compatible devices and have never
required this auto-reset behaviour for at least the whole git era.
Starting to rely on it now seems risky, offers no benefit, and
indeed breaks at least the Ingenic JZ4780's UARTs which reads
garbage when the RX FIFO is enabled if we don't explicitly reset it.
3) By only resetting the FIFOs if they're enabled, the behaviour of
serial8250_do_startup() during boot now depends on what the value of
FCR is before the 8250 driver is probed. This in itself seems
questionable and leaves us with FCR=0 & no FIFO reset if the UART
was used by 8250_early, otherwise it depends upon what the
bootloader left behind.
4) Although the naming of serial8250_clear_fifos() may be unclear, it
is clear that callers of it expect that it will disable FIFOs. Both
serial8250_do_startup() & serial8250_do_shutdown() contain comments
to that effect, and other callers explicitly re-enable the FIFOs
after calling serial8250_clear_fifos(). The premise of that patch
that disabling the FIFOs is incorrect therefore seems wrong.
For these reasons, this reverts commit f6aa5beb45 ("serial: 8250: Fix
clearing FIFOs in RS485 mode again").
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: f6aa5beb45 ("serial: 8250: Fix clearing FIFOs in RS485 mode again").
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Daniel Jedrychowski <avistel@gmail.com>
Cc: Marek Vasut <marex@denx.de>
Cc: linux-mips@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Cc: stable <stable@vger.kernel.org> # 4.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a serial port gets faulty or gets flooded with inputs, its interrupt
handler starts to work double time to get the characters to the workqueue
for the tty layer to handle them. When this busy time on the serial/tty
subsystem happens during boot, where it is also busy on the userspace
trying to initialise, some processes can continuously get preempted
and will be on hold until the interrupts subside.
The fix is to backoff on processing received characters for a specified
amount of time when an input overrun is seen (received a new character
before the previous one is processed). This only stops receive and will
continue to transmit characters to serial port. After the backoff period
is done, it receive will be re-enabled. This is optional and will only
be enabled by setting 'overrun-throttle-ms' in the dts.
Signed-off-by: Darwin Dingel <darwin.dingel@alliedtelesis.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial8250_register_8250_port calls uart_config_port, which calls
config_port on the port before it tries to power on the port. So we need
the port to be on before calling serial8250_register_8250_port. Change
the code to always do a runtime resume in probe before registering port,
and always do a runtime suspend in remove.
This basically reverts the change in commit 68e5fc4a25 ("tty: serial:
8250_mtk: use pm_runtime callbacks for enabling"), but still use
pm_runtime callbacks.
Fixes: 68e5fc4a25 ("tty: serial: 8250_mtk: use pm_runtime callbacks for enabling")
Signed-off-by: Peter Shih <pihsun@chromium.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Modify uart register to support DMA function.
Signed-off-by: Long Cheng <long.cheng@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Let's take advantage of the new ("serial: core: Allow processing sysrq
at port unlock time") to handle sysrqs more cleanly.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is way too easy to miss enabling SERIAL_OF_PLATFORM which would
result in the inability for the kernel to have a valid console device,
which can be seen with:
Warning: unable to open an initial console.
and then:
Run /init as init process
Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000100
Since SERIAL_OF_PLATFORM already depends on SERIAL_8250 && OF there
really is no drawback to defaulting this config to the value of
SERIAL_8250.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
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>
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>
