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>
Due to the complexities of modern Qualcomm SoCs, about a half dozen drivers
must successfully probe before the clocks for the console are present, and
the console can successfully probe. Depending on several random factors
such as probe order and modules vs builtin, msm_serial may not be able to
successfully probe for some, at which point, __init annotated functions
may become unmapped. If this occurs, msm_console_setup() will be called
from the probe path, but will no longer exist, resulting in a kernel
panic.
Resolve this issue by removing the __init annotation from
msm_console_setup().
Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Exynos 5260, like the 5433, appears to require baud clock as
well as pclk to be running before accessing any of the registers,
otherwise an external abort is raised.
The serial driver already enables baud clock when required, but only
if it knows which clock is baud clock. On older SoCs baud clock may be
selected from a number of possible clocks so to support this the driver
only selects which clock to use for baud clock when a port is opened,
at which point the desired baud rate is known and the best clock can be
selected.
The result is that there are a number of circumstances in which
registers are accessed without first explicitly enabling baud clock:
- while the driver is being initialised
- the initial parts of opening a port for the first time
- when resuming if the port hasn't been already opened
The 5433 overcomes this currently by marking the baud clock as
CLK_IGNORE_UNUSED, so the clock is always enabled, however
for the 5260 I've been trying to avoid this.
This change adds code to pick the first available clock to use
as baud clock and enables it while initialising the driver.
This code wouldn't be sufficient on a SoC which supports
multiple possible baud clock sources _and_ requires the
correct baud clock to be enabled before accessing any of the
serial port registers (in particular the register which selects
which clock to use as the baud clock). As far as I know
such hardware doesn't exist.
Signed-off-by: Stuart Menefy <stuart.menefy@mathembedded.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If RX is disabled while there are still unprocessed bytes in RX FIFO,
cdns_uart_handle_rx() called from interrupt handler will get stuck in
the receive loop as read bytes will not get removed from the RX FIFO
and CDNS_UART_SR_RXEMPTY bit will never get set.
Avoid the stuck handler by checking first if RX is disabled. port->lock
protects against race with RX-disabling functions.
This HW behavior was mentioned by Nathan Rossi in 43e98facc4a3 ("tty:
xuartps: Fix RX hang, and TX corruption in termios call") which fixed a
similar issue in cdns_uart_set_termios().
The behavior can also be easily verified by e.g. setting
CDNS_UART_CR_RX_DIS at the beginning of cdns_uart_handle_rx() - the
following loop will then get stuck.
Resetting the FIFO using RXRST would not set RXEMPTY either so simply
issuing a reset after RX-disable would not work.
I observe this frequently on a ZynqMP board during heavy RX load at 1M
baudrate when the reader process exits and thus RX gets disabled.
Fixes: 61ec901698 ("tty/serial: add support for Xilinx PS UART")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
unlikely has already included in IS_ERR(),
so just remove redundant likely annotation.
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
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>
Here are some small tty and serial fixes for 5.0-rc6.
Nothing huge, just a few small fixes for reported issues. The speakup
fix is in here as it is a tty operation issue.
All of these have been in linux-next for a while with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are some small tty and serial fixes for 5.0-rc6.
Nothing huge, just a few small fixes for reported issues. The speakup
fix is in here as it is a tty operation issue.
All of these have been in linux-next for a while with no reported
problems"
* tag 'tty-5.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: fix race between flush_to_ldisc and tty_open
staging: speakup: fix tty-operation NULL derefs
serial: sh-sci: Do not free irqs that have already been freed
serial: 8250_pci: Make PCI class test non fatal
tty: serial: 8250_mtk: Fix potential NULL pointer dereference
The MODE1 register bits have different values for different ICs.
This patch corrects the initial setting of this register in accordance
with the datasheets, which will allow you to get the expected values
when debugging the driver.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch set contains a handful of mostly-independent patches:
* A patch that causes our port to respect TIF_NEED_RESCHED, which fixes
CONFIG_PREEMPT=y kernels.
* A fix to avoid double-put on OF nodes.
* Fix a misspelling of target in our Kconfig.
* Generic PCIe is enabled in our defconfig.
* A fix to our SBI early console to properly handle line endings.
* A fix such that max_low_pfn is counted in PFNs.
* A change to TASK_UNMAPPED_BASE to match what other arches do.
This has passed by standard "boot Fedora" flow.
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Merge tag 'riscv-for-linus-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux
Pull RISC-V fixes from Palmer Dabbelt:
"This contains a handful of mostly-independent patches:
- make our port respect TIF_NEED_RESCHED, which fixes
CONFIG_PREEMPT=y kernels
- fix double-put of OF nodes
- fix a misspelling of target in our Kconfig
- generic PCIe is enabled in our defconfig
- fix our SBI early console to properly handle line
endings
- fix max_low_pfn being counted in PFNs
- a change to TASK_UNMAPPED_BASE to match what other
arches do
This has passed my standard 'boot Fedora' flow"
* tag 'riscv-for-linus-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
riscv: Adjust mmap base address at a third of task size
riscv: fixup max_low_pfn with PFN_DOWN.
tty/serial: use uart_console_write in the RISC-V SBL early console
RISC-V: defconfig: Add CRYPTO_DEV_VIRTIO=y
RISC-V: defconfig: Enable Generic PCIE by default
RISC-V: defconfig: Move CONFIG_PCI{,E_XILINX}
RISC-V: Kconfig: fix spelling mistake "traget" -> "target"
RISC-V: asm/page.h: fix spelling mistake "CONFIG_64BITS" -> "CONFIG_64BIT"
RISC-V: fix bad use of of_node_put
RISC-V: Add _TIF_NEED_RESCHED check for kernel thread when CONFIG_PREEMPT=y
There still is a race window after the commit b027e2298b
("tty: fix data race between tty_init_dev and flush of buf"),
and we encountered this crash issue if receive_buf call comes
before tty initialization completes in tty_open and
tty->driver_data may be NULL.
CPU0 CPU1
---- ----
tty_open
tty_init_dev
tty_ldisc_unlock
schedule
flush_to_ldisc
receive_buf
tty_port_default_receive_buf
tty_ldisc_receive_buf
n_tty_receive_buf_common
__receive_buf
uart_flush_chars
uart_start
/*tty->driver_data is NULL*/
tty->ops->open
/*init tty->driver_data*/
it can be fixed by extending ldisc semaphore lock in tty_init_dev
to driver_data initialized completely after tty->ops->open(), but
this will lead to get lock on one function and unlock in some other
function, and hard to maintain, so fix this race only by checking
tty->driver_data when receiving, and return if tty->driver_data
is NULL, and n_tty_receive_buf_common maybe calls uart_unthrottle,
so add the same check.
Because the tty layer knows nothing about the driver associated with the
device, the tty layer can not do anything here, it is up to the tty
driver itself to check for this type of race. Fix up the serial driver
to correctly check to see if it is finished binding with the device when
being called, and if not, abort the tty calls.
[Description and problem report and testing from Li RongQing, I rewrote
the patch to be in the serial layer, not in the tty core - gregkh]
Reported-by: Li RongQing <lirongqing@baidu.com>
Tested-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Wang Li <wangli39@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Clang warns:
drivers/tty/serial/mps2-uart.c:351:6: warning: logical not is only
applied to the left hand side of this bitwise operator
[-Wlogical-not-parentheses]
if (!mps_port->flags & UART_PORT_COMBINED_IRQ) {
^ ~
drivers/tty/serial/mps2-uart.c:351:6: note: add parentheses after the
'!' to evaluate the bitwise operator first
if (!mps_port->flags & UART_PORT_COMBINED_IRQ) {
^
( )
drivers/tty/serial/mps2-uart.c:351:6: note: add parentheses around left
hand side expression to silence this warning
if (!mps_port->flags & UART_PORT_COMBINED_IRQ) {
^
( )
1 warning generated.
As it was intended for this check to be the inverse of the one at the
bottom of mps2_init_port, add parentheses around the whole conditional.
Fixes: 775ea4ea2f ("serial: mps2-uart: support combined irq")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Vladimir Murzin <vladimir.murzin@arm.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/344
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It turns out that some designs went for implementing only combined
interrupt for rx, tx and overrun, which is currently not supported
by the driver. Support of combined irq is built on top of existent
irq handlers and activated automatically if only single irq was
specified in device tree.
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some designs, like MPS3, expose number of virtual serial ports which
already close or exceeds MPS2_MAX_PORTS. Increasing MPS2_MAX_PORTS
would have negative impact (in terms of memory consumption) on tiny
MPS2 platform which, in fact, has only one physically populated UART.
Start with converting existent static port array to idr. As a bonus it
make driver not to fail in case when no alias was specified in device
tree.
Note: there is no need in idr_destroy() because code doesn't unload
since ce87122911 ("serial: mps2-uart: make driver explicitly non-modular")
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since IRQs might be muxed on some parts, we need to pay attention when we
are freeing them.
Otherwise we get the ugly WARNING "Trying to free already-free IRQ 20".
Fixes: 628c534ae7 ("serial: sh-sci: Improve support for separate TEI and DRI interrupts")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Chris Brandt <chris.brandt@renesas.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>
The Tegra Combined UART (TCU) is a mailbox-based mechanism that allows
multiplexing multiple "virtual UARTs" into a single hardware serial
port. The TCU is the primary serial port on Tegra194 devices.
Add a TCU driver utilizing the mailbox framework, as the used mailboxes
are part of Tegra HSP blocks that are already controlled by the Tegra
HSP mailbox driver.
Based on work by Mikko Perttunen <mperttunen@nvidia.com>.
Signed-off-by: Thierry Reding <treding@nvidia.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>
Add DMA support for 32-bit variant of the LPUART, such as LS1021A.
Signed-off-by: Tomonori Sakita <tomonori.sakita@sord.co.jp>
Signed-off-by: Atsushi Nemoto <atsushi.nemoto@sord.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The geni set/get_mctrl() functions currently do nothing unless
hardware flow control is enabled. Remove this arbitrary limitation.
Suggested-by: Johan Hovold <johan@kernel.org>
Fixes: 8a8a66a1a1 ("tty: serial: qcom_geni_serial: Add support for flow control")
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Johan Hovold <johan@kernel.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>
When probing the HSUART, it is put in loopback mode in order to prevent a
potential issue that may happen on RX (Errata HSUART.1).
serial_lpc32xx_startup() moves it out of loopback mode but this is too late
to get the kernel boot messages before userspace opens the device.
Also get out of loopback mode in lpc32xx_hsuart_console_setup().
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
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>
At probe, the uart driver tries to get an id from a device tree alias.
When no alias was specified, the driver would return an error and probing
would fail.
Providing an alias for registering a serial device should not be mandatory.
If the device tree does not specify an alias, provide an id from a reserved
range so that the probing can continue.
Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Loys Ollivier <lollivier@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are 2 tty and serial fixes for 5.0-rc2 that resolve some reported
issues.
The first is a simple serial driver fix for a regression that showed up
in 5.0-rc1. The second one resolves a number of reported issues with
the recent tty locking fixes that went into 5.0-rc1. Lots of people
have tested the second one and say it resolves their issues.
Both have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are 2 tty and serial fixes for 5.0-rc2 that resolve some reported
issues.
The first is a simple serial driver fix for a regression that showed
up in 5.0-rc1. The second one resolves a number of reported issues
with the recent tty locking fixes that went into 5.0-rc1. Lots of
people have tested the second one and say it resolves their issues.
Both have been in linux-next with no reported issues"
* tag 'tty-5.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: Don't hold ldisc lock in tty_reopen() if ldisc present
serial: lantiq: Do not swap register read/writes
In RISC-V, the M-mode runtime firmware provide SBI calls for
debug prints. This patch adds earlycon support using RISC-V
SBI console calls. To enable it, just pass "earlycon=sbi" in
kernel parameters.
Signed-off-by: Anup Patel <anup@brainfault.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Use u32 rather than unsigned long for register variables for clarity and
consistency.
Signed-off-by: Ryan Case <ryandcase@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver only supports FIFO mode so setting and checking this variable
is unnecessary. If DMA support is ever added then such checks can be
introduced.
Signed-off-by: Ryan Case <ryandcase@chromium.org>
Reviewed-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The variables of tx_wm and rx_wm were set to the same define value in
all cases, never updated, and the define was sometimes used
interchangably. Remove the variables/function and use the fixed value.
Signed-off-by: Ryan Case <ryandcase@chromium.org>
Reviewed-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A frequent side comment has been to remove the use of writel_relaxed,
readl_relaxed, and mb. This reduces driver complexity and the _relaxed
variants were not known to provide any noticeable performance benefit.
Signed-off-by: Ryan Case <ryandcase@chromium.org>
Reviewed-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Most RX/TX-specific DMA functions are prefixed with "sci_dma_[rt]x_".
Rename the exceptions to increase consistency.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When submitting a DMA request fails in sci_dma_rx_complete(), the driver
tries to fall back to PIO, but that does not work: no more data will be
received, or the kernel will even crash.
Fix this similar as in (but not identical to) sci_submit_rx():
- On SCIF, PIO cannot take over if any DMA transactions are pending,
hence they must be terminated first.
- All active cookies must be invalidated, else rx_timer_fn() may
trigger a NULL pointer dereference.
- Restarting the port is not needed, as it is already running, but
serial port interrupts must be directed back from the DMA engine to
the CPU.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Extract the functionality to direct new serial port interrupts back to
the CPU into its own helper, to prepare for using it from a second
callsite.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The cookies and channel pointer for the DMA receive channel are
invalidated in two places, and one more is planned.
Extract this functionality in a common helper.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:
struct foo {
int stuff;
void *entry[];
};
instance = devm_kzalloc(dev, sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:
instance = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL);
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:
struct foo {
int stuff;
void *entry[];
};
instance = devm_kzalloc(dev, sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:
instance = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL);
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>