Граф коммитов

737825 Коммитов

Автор SHA1 Сообщение Дата
Christian Brauner 4e15f760a4 devpts: comment devpts_mntget()
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-14 13:31:23 +01:00
Christian Brauner a319b01d90 devpts: resolve devpts bind-mounts
Most libcs will still look at /dev/ptmx when opening the master fd of a pty
device. When /dev/ptmx is a bind-mount of /dev/pts/ptmx and the TIOCGPTPEER
ioctl() is used to safely retrieve a file descriptor for the slave side of
the pty based on the master fd, the /proc/self/fd/{0,1,2} symlinks will
point to /. A very simply reproducer for this issue presupposing a libc
that uses TIOCGPTPEER in its openpty() implementation is:

unshare --mount
mount --bind /dev/pts/ptmx /dev/ptmx
chmod 666 /dev/ptmx
script
ls -al /proc/self/fd/0

Having bind-mounts of /dev/pts/ptmx to /dev/ptmx not working correctly is a
regression. In addition, it is also a fairly common scenario in containers
employing user namespaces.

The reason for the current failure is that the kernel tries to verify the
useability of the devpts filesystem without resolving the /dev/ptmx
bind-mount first. This will lead it to detect that the dentry is escaping
its bind-mount. The reason is that while the devpts filesystem mounted at
/dev/pts has the devtmpfs mounted at /dev as its parent mount:

21 -- -- / /dev
-- 21 -- / /dev/pts

devtmpfs and devpts are on different devices

-- -- 0:6  / /dev
-- -- 0:20 / /dev/pts

This has the consequence that the pathname of the parent directory of the
devpts filesystem mount at /dev/pts is /. So if /dev/ptmx is a bind-mount
of /dev/pts/ptmx then the /dev/ptmx bind-mount and the devpts mount at
/dev/pts will end up being located on the same device which is recorded in
the superblock of their vfsmount. This means the parent directory of the
/dev/ptmx bind-mount will be /ptmx:

-- -- ---- /ptmx /dev/ptmx

Without the bind-mount resolution patch the kernel will now perform the
bind-mount escape check directly on /dev/ptmx. The function responsible for
this is devpts_ptmx_path() which calls pts_path() which in turn calls
path_parent_directory(). Based on the above explanation,
path_parent_directory() will yield / as the parent directory for the
/dev/ptmx bind-mount and not the expected /dev. Thus, the kernel detects
that /dev/ptmx is escaping its bind-mount and will set /proc/<pid>/fd/<nr>
to /.

This patch changes the logic to first resolve any bind-mounts. After the
bind-mounts have been resolved (i.e. we have traced it back to the
associated devpts mount) devpts_ptmx_path() can be called. In order to
guarantee correct path generation for the slave file descriptor the kernel
now requires that a pts directory is found in the parent directory of the
ptmx bind-mount. This implies that when doing bind-mounts the ptmx
bind-mount and the devpts mount should have a common parent directory. A
valid example is:

mount -t devpts devpts /dev/pts
mount --bind /dev/pts/ptmx /dev/ptmx

an invalid example is:

mount -t devpts devpts /dev/pts
mount --bind /dev/pts/ptmx /ptmx

This allows us to support:
- calling open on ptmx devices located inside non-standard devpts mounts:
  mount -t devpts devpts /mnt
  master = open("/mnt/ptmx", ...);
  slave = ioctl(master, TIOCGPTPEER, ...);
- calling open on ptmx devices located outside the devpts mount with a
  common ancestor directory:
  mount -t devpts devpts /dev/pts
  mount --bind /dev/pts/ptmx /dev/ptmx
  master = open("/dev/ptmx", ...);
  slave = ioctl(master, TIOCGPTPEER, ...);

while failing on ptmx devices located outside the devpts mount without a
common ancestor directory:
  mount -t devpts devpts /dev/pts
  mount --bind /dev/pts/ptmx /ptmx
  master = open("/ptmx", ...);
  slave = ioctl(master, TIOCGPTPEER, ...);

in which case save path generation cannot be guaranteed.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Suggested-by: Eric Biederman <ebiederm@xmission.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-14 13:31:23 +01:00
Christian Brauner 7d71109df1 devpts: hoist out check for DEVPTS_SUPER_MAGIC
Hoist the check whether we have already found a suitable devpts filesystem
out of devpts_ptmx_path() in preparation for the devpts bind-mount
resolution patch. This is a non-functional change.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-14 13:31:23 +01:00
Joel Stanley f597fbce38 serial: 8250: Add Nuvoton NPCM UART
The Nuvoton UART is almost compatible with the 8250 driver when probed
via the 8250_of driver, however it requires some extra configuration
at startup.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 11:01:19 -08:00
Alexey Khoroshilov ca7c22fc9e serial: mxs-auart: disable clks of Alphascale ASM9260
In case of Alphascale ASM9260 probe() enables s->clk and s->clk_ahb
via mxs_get_clks(), but there is no disable of the clocks.
The patch adds it to error paths and to mxs_auart_remove().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Fixes: 254da0d753 ("serial: mxs-auart: add Alphascale ASM9260 support")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 11:01:19 -08:00
Andy Shevchenko 7d6e2143be serial: 8250_dw: Switch to use acpi_dev_present()
Special settings for APMC0D08 are applied when device is present
in the system. To check its presence we may use acpi_dev_present()
instead of current open coded variant.

Cc: Feng Kan <fkan@apm.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:24:38 -08:00
Uwe Kleine-König 9d1a50a2cc serial: imx: consistently use imx_uart_ as prefix for all functions
Having a fixed prefix helps at several places. It ensures that another
driver doesn't use the same function name which confuses the linker and
tools like ctags. It simplifies working with function tracing and
dynamic printk() support which can filter on function names. And last
but not least it helps the human source code reader to understand if a
given function belongs to a driver or a more general part of the kernel.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:02 -08:00
Uwe Kleine-König 48669b69e3 serial: imx: don't prepare to send if no data is available
serial_core might call the .start_tx callback without any data being
available to send. In this case return early instead of going through
all the setup needed for sending which might include disabling RX in
RS485 half-duplex mode.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:02 -08:00
Uwe Kleine-König 1866541492 serial: imx: Fix handling of TC irq in combination with DMA
When using RS485 half duplex the Transmitter Complete irq is needed to
determine the moment when the transmitter can be disabled. When using
DMA this irq must only be enabled when DMA has completed to transfer all
data. Otherwise the CPU might busily trigger this irq which is not
properly handled and so the also pending irq for the DMA transfer cannot
trigger.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:02 -08:00
Uwe Kleine-König 81ca8e8286 serial: imx: Also enable the aging timer in PIO mode
This allows to increase the RX waterlevel which allows to delay the RRDY
irq. The desired effect is that less irqs are needed to handle
characters and so reduce irq count of the system.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:01 -08:00
Uwe Kleine-König 76821e222c serial: imx: ensure that RX irqs are off if RX is off
Make sure that UCR1.RXDMAEN and UCR1.ATDMAEN (for the DMA case) and
UCR1.RRDYEN (for the PIO case) are off iff UCR1.RXEN is disabled. This
ensures that the fifo isn't read with RX disabled which results in an
exception.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:01 -08:00
Uwe Kleine-König dedc64e02f serial: imx: Stop to receive in .stop_rx()
When the UART is used in DMA mode, .stop_rx() does nothing if the port
isn't suspended. This is wrong as .stop_rx() should stop receiving
characters unconditionally. When the port is about to be closed the DMA
channel is stopped in .shutdown(), so this isn't necessary to be in
.stop_rx() here, too.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:01 -08:00
Uwe Kleine-König 02b0abd3bb serial: imx: setup fifo waterlevel before enabling aging timer
The aging timer fires if there are characters in the RX fifo but the
water level isn't reached yet. Make sure that the waterlevel is
configured before the aging timer is enabled to trigger a DMA request
(UCR1_ATDMAEN).

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:01 -08:00
Uwe Kleine-König 4444dcf1fe serial: imx: use u32 variables with matching names for registers
The serial/imx driver is full of inconsistently named and typed
variables that hold different register values.

Consistently use u32 as type (matching what readl and writel use) and
name the variables after the register whose value they are holding.
This makes it easier to notice when UCR2_RTSEN is written to UCR1.

The only difference introduced by this commit in the compiled driver is
that twice the second argument to warn_slowpath_null() changed because the
two WARN_ON in dma_rx_callback() pass __LINE__ to warn_slowpath_null().

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:01 -08:00
Uwe Kleine-König 0c54922384 serial: imx: simplify check that prevents starting PIO when DMA is in use
The original code looks as follows:

	if (sport->dma_is_enabled) {
		... make sure TX DMA is running, i.e. .dma_is_txing = 1
	}

	if (sport->dma_is_txing)
		return;

As .dma_is_txing can only be true if .dma_is_enabled is, the return can
go at the end of the first if body without an additional check.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:01 -08:00
Uwe Kleine-König 686351f342 serial: imx: simplify some conditions related to dma
Neither .dma_is_txing nor .dma_is_rxing can evaluate to true if
.dma_is_enabled evaluates to false:

The only function that sets .dma_is_txing to a non-zero value is
imx_dma_tx() which is only called if .dma_is_enabled is true. Same for
.dma_is_rxing and start_rx_dma(). And before .dma_is_enabled is set to 0
when imx_shutdown calls imx_disable_dma(), .dma_is_rxing and
.dma_is_txing are reset to zero before, too.

For this reason

	sport->dma_is_enabled && sport->dma_is_rxing

has the same value as

	sport->dma_is_rxing

which allows to simplify three if conditions.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:01 -08:00
Uwe Kleine-König 3a0ab62f43 serial: imx: implement shadow registers for UCRx and UFCR
This reduces the amount of read accesses to the register space by
shadowing the values for five registers that only change on writing
them. There is a single bit in UCR2 that might change without being
written to it, this is handled accordingly.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:01 -08:00
Uwe Kleine-König 27c844261b serial: imx: add wrappers for writel and readl
This prepares implementing shadow copies for the control registers and
additionally provides a good place to hook in debug code to trace
register usage.

Most of this patch was done using pattern substitution:

	perl -p -i -e '
		s/\breadl(?:_relaxed)?\((?:sport->port\.|port->)membase \+/imx_uart_readl(sport,/;
		s/\bwritel(?:_relaxed)?\(([^,]*), (sport->port\.|port->)membase \+/imx_uart_writel(sport, $1,/;
	' drivers/tty/serial/imx.c

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:21:01 -08:00
Palmer Dabbelt afa6b1ccfa tty: New RISC-V SBI console driver
The RISC-V ISA defines a simple console that is availiable via SBI calls
on all systems.  The SBI console is designed to be availiable at all
times, so while it's most natural to use this as an early printk target
it's also possible to use this as the system console when there isn't a
better one availiable.

This patch adds support for the RISC-V SBI console via the HVC
infastructure.  It's entirely independent from our early printk support,
which results in early boot messages appearing twice over the SBI
console.  As far as I can tell that's the fault of our early printk
support (we should support earlycon) as opposed to this driver.

There is one checkpatch.pl warning here: to check the MAINTAINERS file.
They're all matched by the "K: riscv" line.

Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09 10:19:28 -08:00
Uwe Kleine-König 6aed2a8850 serial: imx: document functions that are called with port.lock taken
Consistently indicate being called with irqs off and the port lock taken
for all functions that this applies to.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:36:34 +01:00
Uwe Kleine-König 302e8dcc3f serial: imx: Rename register fields to match newer reference manuals
Only the reference manual for the i.MX1 (I have MC9328MX1RM/D Rev 5 from
2004) uses TDMAEN and RDMAEN for these. All reference manuals for the
newer chips use TXDMAEN and RXDMAEN. Update to the newer name with the
assumption that most imx users don't use an imx1 any more.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:36:34 +01:00
Andy Shevchenko aad76f2c48 serial, pci_ids: Move duplicate IDs to PCI IDs database
PCI ID database is for IDs used across several drivers.
Here is the case for SUNIX combo cards.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:33:04 +01:00
Geert Uytterhoeven e7d75e18d0 serial: xuartps: Fix out-of-bounds access through DT alias
The cdns_uart_port[] array is indexed using a value derived from the
"serialN" alias in DT, which may lead to an out-of-bounds access.

Fix this by adding a range check.

Fixes: 928e926349 ("tty: xuartps: Initialize ports according to aliases")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:30:00 +01:00
Geert Uytterhoeven 96c611c2b7 serial: sirf: Fix out-of-bounds access through DT alias
The sirf_ports[] array is indexed using a value derived from the
"serialN" alias in DT, which may lead to an out-of-bounds access.

Fix this by adding a range check.

Fixes: a6ffe8966a ("serial: sirf: use dynamic method allocate uart structure")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:30:00 +01:00
Geert Uytterhoeven 090fa4b0dc serial: sh-sci: Fix out-of-bounds access through DT alias
The sci_ports[] array is indexed using a value derived from the
"serialN" alias in DT, which may lead to an out-of-bounds access.

Fix this by adding a range check.

Note that the array size is defined by a Kconfig symbol
(CONFIG_SERIAL_SH_SCI_NR_UARTS), so this can even be triggered using a
legitimate DTB.

Fixes: 97ed9790c5 ("serial: sh-sci: Remove unused platform data capabilities field")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:30:00 +01:00
Geert Uytterhoeven 49ee23b718 serial: samsung: Fix out-of-bounds access through serial port index
The s3c24xx_serial_ports[] array is indexed using a value derived from
the "serialN" alias in DT, or from an incrementing probe index, which
may lead to an out-of-bounds access.

Fix this by adding a range check.

Note that the array size is defined by a Kconfig symbol
(CONFIG_SERIAL_SAMSUNG_UARTS), so this can even be triggered using
a legitimate DTB or legitimate board code.

Fixes: 13a9f6c64f ("serial: samsung: Consider DT alias when probing ports")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:30:00 +01:00
Geert Uytterhoeven afc7851fab serial: pxa: Fix out-of-bounds access through serial port index
The serial_pxa_ports[] array is indexed using a value derived from the
"serialN" alias in DT, or from platform data, which may lead to an
out-of-bounds access.

Fix this by adding a range check.

Fixes: 699c20f3e6 ("serial: pxa: add OF support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:29:59 +01:00
Geert Uytterhoeven dd345a31bf serial: mxs-auart: Fix out-of-bounds access through serial port index
The auart_port[] array is indexed using a value derived from the
"serialN" alias in DT, or from platform data, which may lead to an
out-of-bounds access.

Fix this by adding a range check.

Fixes: 1ea6607d4c ("serial: mxs-auart: Allow device tree probing")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:29:59 +01:00
Geert Uytterhoeven 5673444821 serial: imx: Fix out-of-bounds access through serial port index
The imx_ports[] array is indexed using a value derived from the
"serialN" alias in DT, or from platform data, which may lead to an
out-of-bounds access.

Fix this by adding a range check.

Fixes: ff05967a07 ("serial/imx: add of_alias_get_id() reference back")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:29:59 +01:00
Geert Uytterhoeven ffab87fdec serial: fsl_lpuart: Fix out-of-bounds access through DT alias
The lpuart_ports[] array is indexed using a value derived from the
"serialN" alias in DT, which may lead to an out-of-bounds access.

Fix this by adding a range check.

Fixes: c9e2e946fb ("tty: serial: add Freescale lpuart driver support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:29:59 +01:00
Geert Uytterhoeven f9f5786987 serial: arc_uart: Fix out-of-bounds access through DT alias
The arc_uart_ports[] array is indexed using a value derived from the
"serialN" alias in DT, which may lead to an out-of-bounds access.

Fix this by adding a range check.

Note that the array size is defined by a Kconfig symbol
(CONFIG_SERIAL_ARC_NR_PORTS), so this can even be triggered using a
legitimate DTB.

Fixes: ea28fd56fc ("serial/arc-uart: switch to devicetree based probing")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:29:59 +01:00
Uwe Kleine-König 42afa627c3 serial: imx: drop check for enabled dma in .startup
imx_shutdown() calls imx_disable_dma if .dma_is_enabled. So after
imx_shudown() completes, .dma_is_enabled is zero. For this reason
.dma_is_enabled is also zero when imx_startup() is called. So the check
for this variable being zero can be dropped.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:29:59 +01:00
Uwe Kleine-König 4238c00bb1 serial: imx: simplify tracking of dma being initialized
The .dma_is_inited member is only set to a value != 0 when the port's
startup function calls imx_uart_dma_init(). On shutdown of the port
imx_uart_dma_exit is called which sets the value back to 0. So
.dma_is_inited is always 0 when imx_startup() is called (assuming
.startup() and .shutdown() are correctly balanced) and the check for
!sport->dma_is_inited can go away.

This allows to replace .dma_is_inited by a variable local to
imx_startup.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:29:59 +01:00
Uwe Kleine-König 437768962f serial: imx: Only handle irqs that are actually enabled
Handling an irq that isn't enabled can have some undesired side effects.
Some of these are mentioned in the newly introduced code comment. Some
of the irq sources already had their handling right, some don't. Handle
them all in the same consistent way.

The change for USR1_RRDY and USR1_AGTIM drops the check for
dma_is_enabled. This is correct as UCR1_RRDYEN and UCR2_ATEN are always
off if dma is enabled.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:29:58 +01:00
Uwe Kleine-König 0399fd6147 serial: imx: rename variables to match the register names
Now the variable holding the value of register USR1 is called usr1
instead of sts which is more straight forward. The same is also done for
sts2 which is called usr2 now.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:29:58 +01:00
Uwe Kleine-König 135ccb0129 serial: imx: drop if that always evaluates to true
The check sts & USR1_DTRD was just evaluated to true two lines above.
So this change doesn't have any effect on the semantic of the driver.

Fixes: 27e1650105 ("serial: imx: implement DSR irq handling for DTE mode")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 15:29:58 +01:00
Colin Ian King 0ef5a6e09b serial: mvebu-uart: remove duplicated bit-wise or of STAT_FRM_ERR
Bit pattern STAT_FRM_ERR is being bit-wise or'd twice; remove the
redundant 2nd STAT_FRM_ERR

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:46:03 +01:00
Troy Kisky 45ca673e81 tty: serial: imx: allow breaks to be received when using dma
This allows me to login after sending a break when service
serial-getty@ttymxc0.service is running

The "tty_insert_flip_char(port, 0, TTY_BREAK)" in clear_rx_errors
fixes this by allowing the higher layers to see a break.

Also, call uart_handle_break to handle possible
"secure attention key."

FYI: Martin said the ROM sdma firmware works with this patch,
but external sdma firmware still does not send breaks on a
i.mx6UL

Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
Tested-by: Martin Hicks <mort@bork.org>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:44:33 +01:00
Joshua Scott 914eaf935e serial: 8250_dw: Allow TX FIFO to drain before writing to UART_LCR
An issue has been observed on the Marvell Armada 38x serial port.

Writes to UART_LCR can result in characters that are currently held in the
TX FIFO being lost rather than sent, even if the userspace process has
attempted to flush them.

This is most visible when using the "resize" command (tested on Busybox),
where we have observed the escape code for restoring cursor position
becoming mangled.

Signed-off-by: Joshua Scott <joshua.scott@alliedtelesis.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:40:22 +01:00
Ulrich Hecht b96408b474 serial: sh-sci: use hrtimer for receive timeout
High latencies of classic timers cause performance issues for high-
speed serial transmissions. This patch transforms rx_timer into an
hrtimer to reduce the minimum latency.

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:40:22 +01:00
Vignesh R 08fb00c64f serial: 8250: 8250_omap: Fix throttling when DMA is enabled
omap_8250_throttle() is called when tty RX buffer is about to overflow
and can no longer keep up with the rate at which UART is receiving data.
So, the expectation of this callback, is that UART stops RX and asserts
HW flow control to signal the sender to stop sending more data.
omap_8250_throttle() disables RX FIFO interrupts thus FIFO is no longer
serviced, leading to assertion of flow control once RX FIFO is full.
But, this does not work when DMA is enabled as driver keeps queuing new
RX DMA request in completion handler without brothering about throttling
request made by the higher layer.
This patch introduces a flag that can be used to determine whether or
not to queue next RX DMA request based on throttling request.

Without this patch, tty buffer overflows are reported at higher
baudrates.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:40:22 +01:00
Vignesh R 2e9fe53910 serial: 8250: Don't service RX FIFO if interrupts are disabled
Currently, data in RX FIFO is read based on UART_LSR register state even
if RDI and RLSI interrupts are disabled in UART_IER register.
This is because when IRQ handler is called due to TX FIFO empty event,
RX FIFO is serviced based on UART_LSR register status instead of
UART_IIR status. This defeats the purpose of disabling UART RX
FIFO interrupts during throttling(see, omap_8250_throttle()) as IRQ
handler continues to drain UART RX FIFO resulting in overflow of buffer
at tty layer.
Fix this by making sure that driver drains UART RX FIFO only when
UART_IIR_RDI is set along with UART_LSR_BI or UART_LSR_DR bits.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:40:22 +01:00
Sergei Shtylyov 890fb16b4c DT: serial: renesas,sci-serial: document R8A77980 bindings
R-Car V3H (R8A77980) SoC has the R-Car gen3 compatible SCIF and HSCIF ports,
so document the SoC specific bindings.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:40:22 +01:00
Jan Kundrát 1a9ab351fb gpio: serial: max310x: Use HW type for gpio_chip's label
Some debugging tools (/sys/kernel/debug/gpio, `lsgpio`) use the
gpio_chip's label for displaying an additional context. Right now, the
information duplicates stuff which is already available from the
parent's device. This is how e.g. `lsgpio`'s output looks like:

  GPIO chip: gpiochip2, "spi1.2", 16 GPIO lines

Comparing the output of other GPIO expanders that I have available:

  gpiochip4: GPIOs 464-479, parent: spi/spi1.1, mcp23s17, can sleep:
  gpiochip5: GPIOs 448-463, parent: i2c/0-0020, pca9555, can sleep:
  gpiochip2: GPIOs 496-511, parent: spi/spi1.2, spi1.2, can sleep:

This patch ensures that the type of the real HW device is shown instead
of duplicating the SPI path:

  gpiochip2: GPIOs 496-511, parent: spi/spi1.2, MAX14830, can sleep:

Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:40:22 +01:00
Uwe Kleine-König eefadcbca7 serial: altera: set RRDY flag also without irq
The UART can be operated without an irq. In this case a timer is setup
that regularily calls altera_uart_interrupt(). The receiving part
depends on pp->imr having the bit ALTERA_UART_STATUS_RRDY_MSK set,
otherwise altera_uart_rx_chars() is never called. So ensure that the bit
gets set (disguised as ALTERA_UART_CONTROL_RRDY_MSK) by not returning
early from altera_uart_startup() if port->irq is 0.

This doesn't affect the hardware as the ALTERA_UART_CONTROL_RRDY_MSK bit
isn't actually written to the control register.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:30:09 +01:00
Uwe Kleine-König 2ea6ad8bc6 serial: altera: don't enable any irq if the device doesn't feature an irq
If the irq line of an altera UART device isn't used to report interrupts
for this device the driver better ensures that this device doesn't pull
this line to active state and so disturb the whatever might be connected
to this line.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:30:09 +01:00
Uwe Kleine-König 0e254963b6 serial: altera: ensure port->regshift is honored consistently
Most register accesses in the altera driver honor port->regshift by
using altera_uart_writel(). There are a few accesses however that were
missed when the driver was converted to use port->regshift and some
others were added later in commit 4d9d7d896d ("serial: altera_uart:
add earlycon support").

Fixes: 2780ad42f5 ("tty: serial: altera_uart: Use port->regshift to store bus shift")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:30:09 +01:00
Kees Cook f54450ad19 console: Drop added "static" for newport_con
Commit 4fe505119778 ("console: Expand dummy functions for CFI") accidentally
added "static" to newport_con instance of struct consw, while trying to
normalize the declarations. This, however, needed to stay non-static as it
has an extern.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 4fe505119778 ("console: Expand dummy functions for CFI")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:12:38 +01:00
Kees Cook c396a5bf45 console: Expand dummy functions for CFI
This expands the no-op dummy functions into full prototypes to avoid
indirect call mismatches when running under Control Flow Integrity
checking, like with Clang's -fsanitize=cfi.

Co-Developed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-27 10:17:33 +01:00
Kees Cook 209f668cd2 console: Fill in struct consw argument names
Reading the function declarations for the console callbacks lacks any
hints as to what the arguments are. Instead of going and digging around in
various implementations that may each only have a subset of the callbacks,
name all the arguments in the declaration. This has no functional change.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-27 10:17:33 +01:00