commit 74e1eb3b4a upstream.
Driver's tx_empty callback should signal when the transmit shift register
is empty. So when the last character has been sent.
STAT_TX_FIFO_EMP bit signals only that HW transmit FIFO is empty, which
happens when the last byte is loaded into transmit shift register.
STAT_TX_EMP bit signals when the both HW transmit FIFO and transmit shift
register are empty.
So replace STAT_TX_FIFO_EMP check by STAT_TX_EMP in mvebu_uart_tx_empty()
callback function.
Fixes: 30530791a7 ("serial: mvebu-uart: initial support for Armada-3700 serial port")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20210911132017.25505-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d7aff291d0 ]
Oxford Semiconductor 950 serial port devices have a 128-byte FIFO and in
the enhanced (650) mode, which we select in `autoconfig_has_efr' with
the ECB bit set in the EFR register, they support the receive interrupt
trigger level selectable with FCR bits 7:6 from the set of 16, 32, 112,
120. This applies to the original OX16C950 discrete UART[1] as well as
950 cores embedded into more complex devices.
For these devices we set the default to 112, which sets an excessively
high level of 112 or 7/8 of the FIFO capacity, unlike with other port
types where we choose at most 1/2 of their respective FIFO capacities.
Additionally we don't make the trigger level configurable. Consequently
frequent input overruns happen with high bit rates where hardware flow
control cannot be used (e.g. terminal applications) even with otherwise
highly-performant systems.
Lower the default receive interrupt trigger level to 32 then, and make
it configurable. Document the trigger levels along with other port
types, including the set of 16, 32, 64, 112 for the transmit interrupt
as well[2].
References:
[1] "OX16C950 rev B High Performance UART with 128 byte FIFOs", Oxford
Semiconductor, Inc., DS-0031, Sep 05, Table 10: "Receiver Trigger
Levels", p. 22
[2] same, Table 9: "Transmit Interrupt Trigger Levels", p. 22
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106260608480.37803@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e5227c5109 upstream.
Make sure only actual 8 bits of the IIR register are used in determining
the port type in `autoconfig'.
The `serial_in' port accessor returns the `unsigned int' type, meaning
that with UPIO_AU, UPIO_MEM16, UPIO_MEM32, and UPIO_MEM32BE access types
more than 8 bits of data are returned, of which the high order bits will
often come from bus lines that are left floating in the data phase. For
example with the MIPS Malta board's CBUS UART, where the registers are
aligned on 8-byte boundaries and which uses 32-bit accesses, data as
follows is returned:
YAMON> dump -32 0xbf000900 0x40
BF000900: 1F000942 1F000942 1F000900 1F000900 ...B...B........
BF000910: 1F000901 1F000901 1F000900 1F000900 ................
BF000920: 1F000900 1F000900 1F000960 1F000960 ...........`...`
BF000930: 1F000900 1F000900 1F0009FF 1F0009FF ................
YAMON>
Evidently high-order 24 bits return values previously driven in the
address phase (the 3 highest order address bits used with the command
above are masked out in the simple virtual address mapping used here and
come out at zeros on the external bus), a common scenario with bus lines
left floating, due to bus capacitance.
Consequently when the value of IIR, mapped at 0x1f000910, is retrieved
in `autoconfig', it comes out at 0x1f0009c1 and when it is right-shifted
by 6 and then assigned to 8-bit `scratch' variable, the value calculated
is 0x27, not one of 0, 1, 2, 3 expected in port type determination.
Fix the issue then, by assigning the value returned from `serial_in' to
`scratch' first, which masks out 24 high-order bits retrieved, and only
then right-shift the resulting 8-bit data quantity, producing the value
of 3 in this case, as expected. Fix the same issue in `serial_dl_read'.
The problem first appeared with Linux 2.6.9-rc3 which predates our repo
history, but the origin could be identified with the old MIPS/Linux repo
also at: <git://git.kernel.org/pub/scm/linux/kernel/git/ralf/linux.git>
as commit e0d2356c0777 ("Merge with Linux 2.6.9-rc3."), where code in
`serial_in' was updated with this case:
+ case UPIO_MEM32:
+ return readl(up->port.membase + offset);
+
which made it produce results outside the unsigned 8-bit range for the
first time, though obviously it is system dependent what actual values
appear in the high order bits retrieved and it may well have been zeros
in the relevant positions with the system the change originally was
intended for. It is at that point that code in `autoconf' should have
been updated accordingly, but clearly it was overlooked.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org # v2.6.12+
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106260516220.37803@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fcb10ee27f ]
We should be very careful about the register values that will be used
for division or modulo operations, althrough the possibility that the
UARTBAUD register value is zero is very low, but we had better to deal
with the "bad data" of hardware in advance to avoid division or modulo
by zero leading to undefined kernel behavior.
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20210427021226.27468-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 08a84410a0 upstream.
Stop dmaengine transfer in sci_stop_tx(). Otherwise, the following
message is possible output when system enters suspend and while
transferring data, because clearing TIE bit in SCSCR is not able to
stop any dmaengine transfer.
sh-sci e6550000.serial: ttySC1: Unable to drain transmitter
Note that this driver has already used some #ifdef in the .c file
so that this patch also uses #ifdef to fix the issue. Otherwise,
build errors happens if the CONFIG_SERIAL_SH_SCI_DMA is disabled.
Fixes: 73a19e4c03 ("serial: sh-sci: Add DMA support.")
Cc: <stable@vger.kernel.org> # v4.9+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20210610110806.277932-1-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3890e3dea3 ]
The macro "spi_register_driver" invokes the function
"__spi_register_driver()" which has a return type of int and can fail,
returning a negative value in such a case. This is currently ignored and
the init() function yields success even if the spi driver failed to
register.
Fix this by collecting the return value of "__spi_register_driver()" and
also unregister the uart driver in case of failure.
Cc: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Atul Gopinathan <atulgopinathan@gmail.com>
Link: https://lore.kernel.org/r/20210503115736.2104747-12-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f264c6f6ae ]
Incorrect characters are observed on console during boot. This issue occurs
when init/main.c is modifying termios settings to open /dev/console on the
rootfs.
This patch adds a waiting loop in set_termios to wait for TX shift register
empty (and TX FIFO if any) before stopping serial port.
Fixes: 48a6092fb4 ("serial: stm32-usart: Add STM32 USART Driver")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-4-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 2f70e49ed8 upstream.
At the moment opening a serial device node (such as /dev/ttyS3)
succeeds even if there is no actual serial device behind it.
Reading/writing/ioctls fail as expected because the uart port is not
initialized (the type is PORT_UNKNOWN) and the TTY_IO_ERROR error state
bit is set fot the tty.
However setting line discipline does not have these checks
8250_port.c (8250 is the default choice made by univ8250_console_init()).
As the result of PORT_UNKNOWN, uart_port::iobase is NULL which
a platform translates onto some address accessing which produces a crash
like below.
This adds tty_port_initialized() to uart_set_ldisc() to prevent the crash.
Found by syzkaller.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Link: https://lore.kernel.org/r/20201203055834.45838-1-aik@ozlabs.ru
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d96f04d347 upstream.
It has been observed that once per 300-1300 port openings the first
transmitted byte is being corrupted on AM3352 ("v" written to FIFO appeared
as "e" on the wire). It only happened if single byte has been transmitted
right after port open, which means, DMA is not used for this transfer and
the corruption never happened afterwards.
Therefore I've carefully re-read the MDR1 errata (link below), which says
"when accessing the MDR1 registers that causes a dummy under-run condition
that will freeze the UART in IrDA transmission. In UART mode, this may
corrupt the transferred data". Strictly speaking,
omap_8250_mdr1_errataset() performs a read access and if the value is the
same as should be written, exits without errata-recommended FIFO reset.
A brief check of the serial_omap_mdr1_errataset() from the competing
omap-serial driver showed it has no read access of MDR1. After removing the
read access from omap_8250_mdr1_errataset() the data corruption never
happened any more.
Link: https://www.ti.com/lit/er/sprz360i/sprz360i.pdf
Fixes: 61929cf016 ("tty: serial: Add 8250-core based omap driver")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Link: https://lore.kernel.org/r/20201210055257.1053028-1-alexander.sverdlin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 912ab37c79 upstream.
Mediatek 8250 port supports speed higher than uartclk / 16. If the baud
rates in both the new and the old termios setting are higher than
uartclk / 16, the WARN_ON in uart_get_baud_rate() will be triggered.
Passing NULL as the old termios so uart_get_baud_rate() will use
uartclk / 16 - 1 as the new baud rate which will be replaced by the
original baud rate later by tty_termios_encode_baud_rate() in
mtk8250_set_termios().
Fixes: 551e553f0d ("serial: 8250_mtk: Fix high-speed baud rates clamping")
Signed-off-by: Claire Chang <tientzu@chromium.org>
Link: https://lore.kernel.org/r/20201102120749.374458-1-tientzu@chromium.org
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 0fb9342d06 ]
parse_options() in drivers/tty/serial/earlycon.c calls uart_parse_earlycon
in drivers/tty/serial/serial_core.c therefore selecting SERIAL_EARLYCON
should automatically select SERIAL_CORE, otherwise will result in symbol
not found error during linking if SERIAL_CORE is not configured as builtin
Fixes: 9aac588759 ("tty/serial: add generic serial earlycon")
Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Link: https://lore.kernel.org/r/20200828123949.2642-1-ztong0001@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7d31676a8d ]
Some variants of the samsung tty driver can pick which clock
to use for their baud rate generation. In the DT conversion,
a default clock was selected to be used if a specific one wasn't
assigned and then a comparison of which clock rate worked better
was done. Unfortunately, the comparison was implemented in such
a way that only the default clock was ever actually compared.
Fix this by iterating through all possible clocks, except when a
specific clock has already been picked via clk_sel (which is
only possible via board files).
Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/BN6PR04MB06604E63833EA41837EBF77BA3A30@BN6PR04MB0660.namprd04.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7cf4df30a9 ]
Terminate and flush DMA internal buffers, before pushing RX data to
higher layer. Otherwise, this will lead to data corruption, as driver
would end up pushing stale buffer data to higher layer while actual data
is still stuck inside DMA hardware and has yet not arrived at the
memory.
While at that, replace deprecated dmaengine_terminate_all() with
dmaengine_terminate_async().
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-2-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f19c3f6c81 ]
When port's throttle callback is called, it should stop pushing any more
data into TTY buffer to avoid buffer overflow. This means driver has to
stop HW from receiving more data and assert the HW flow control. For
UARTs with auto HW flow control (such as 8250_omap) manual assertion of
flow control line is not possible and only way is to allow RX FIFO to
fill up, thus trigger auto HW flow control logic.
Therefore make sure that 8250 generic IRQ handler does not drain data
when port is stopped (i.e UART_LSR_DR is unset in read_status_mask). Not
servicing, RX FIFO would trigger auto HW flow control when FIFO
occupancy reaches preset threshold, thus halting RX.
Since, error conditions in UART_LSR register are cleared just by reading
the register, data has to be drained in case there are FIFO errors, else
error information will lost.
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319103230.16867-2-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e0a851fe6b upstream.
If the call to uart_add_one_port() in serial8250_register_8250_port()
fails, a half-initialized entry in the serial_8250ports[] array is left
behind.
A subsequent reprobe of the same serial port causes that entry to be
reused. Because uart->port.dev is set, uart_remove_one_port() is called
for the half-initialized entry and bails out with an error message:
bcm2835-aux-uart 3f215040.serial: Removing wrong port: (null) != (ptrval)
The same happens on failure of mctrl_gpio_init() since commit
4a96895f74 ("tty/serial/8250: use mctrl_gpio helpers").
Fix by zeroing the uart->port.dev pointer in the probe error path.
The bug was introduced in v2.6.10 by historical commit befff6f5bf5f
("[SERIAL] Add new port registration/unregistration functions."):
https://git.kernel.org/tglx/history/c/befff6f5bf5f
The commit added an unconditional call to uart_remove_one_port() in
serial8250_register_port(). In v3.7, commit 835d844d1a ("8250_pnp:
do pnp probe before legacy probe") made that call conditional on
uart->port.dev which allows me to fix the issue by zeroing that pointer
in the error path. Thus, the present commit will fix the problem as far
back as v3.7 whereas still older versions need to also cherry-pick
835d844d1a.
Fixes: 835d844d1a ("8250_pnp: do pnp probe before legacy probe")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v2.6.10
Cc: stable@vger.kernel.org # v2.6.10: 835d844d1a: 8250_pnp: do pnp probe before legacy
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/b4a072013ee1a1d13ee06b4325afb19bda57ca1b.1589285873.git.lukas@wunner.de
[iwamatsu: Backported to 4.4, 4.9: adjust context]
Signed-off-by: Nobuhiro Iwamatsu (CIP) <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 89efbe70b2 upstream.
pl011_probe() calls pl011_setup_port() to reserve an amba_ports[] entry,
then calls pl011_register_port() to register the uart driver with the
tty layer.
If registration of the uart driver fails, the amba_ports[] entry is not
released. If this happens 14 times (value of UART_NR macro), then all
amba_ports[] entries will have been leaked and driver probing is no
longer possible. (To be fair, that can only happen if the DeviceTree
doesn't contain alias IDs since they cause the same entry to be used for
a given port.) Fix it.
Fixes: ef2889f7ff ("serial: pl011: Move uart_register_driver call to device")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v3.15+
Cc: Tushar Behera <tushar.behera@linaro.org>
Link: https://lore.kernel.org/r/138f8c15afb2f184d8102583f8301575566064a6.1597316167.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 27afac93e3 upstream.
If probing of a pl011 gets deferred until after free_initmem(), an oops
ensues because pl011_console_match() is called which has been freed.
Fix by removing the __init attribute from the function and those it
calls.
Commit 10879ae5f1 ("serial: pl011: add console matching function")
introduced pl011_console_match() not just for early consoles but
regular preferred consoles, such as those added by acpi_parse_spcr().
Regular consoles may be registered after free_initmem() for various
reasons, one being deferred probing, another being dynamic enablement
of serial ports using a DeviceTree overlay.
Thus, pl011_console_match() must not be declared __init and the
functions it calls mustn't either.
Stack trace for posterity:
Unable to handle kernel paging request at virtual address 80c38b58
Internal error: Oops: 8000000d [#1] PREEMPT SMP ARM
PC is at pl011_console_match+0x0/0xfc
LR is at register_console+0x150/0x468
[<80187004>] (register_console)
[<805a8184>] (uart_add_one_port)
[<805b2b68>] (pl011_register_port)
[<805b3ce4>] (pl011_probe)
[<80569214>] (amba_probe)
[<805ca088>] (really_probe)
[<805ca2ec>] (driver_probe_device)
[<805ca5b0>] (__device_attach_driver)
[<805c8060>] (bus_for_each_drv)
[<805c9dfc>] (__device_attach)
[<805ca630>] (device_initial_probe)
[<805c90a8>] (bus_probe_device)
[<805c95a8>] (deferred_probe_work_func)
Fixes: 10879ae5f1 ("serial: pl011: add console matching function")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v4.10+
Cc: Aleksey Makarov <amakarov@marvell.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Christopher Covington <cov@codeaurora.org>
Link: https://lore.kernel.org/r/f827ff09da55b8c57d316a1b008a137677b58921.1597315557.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8c6c378b0c upstream.
In few older Samsung SoCs like s3c2410, s3c2412
and s3c2440, UART IP is having 2 interrupt lines.
However, in other SoCs like s3c6400, s5pv210,
exynos5433, and exynos4210 UART is having only 1
interrupt line. Due to this, "platform_get_irq(platdev, 1)"
call in the driver gives the following false-positive error:
"IRQ index 1 not found" on newer SoC's.
This patch adds the condition to check for Tx interrupt
only for the those SoC's which have 2 interrupt lines.
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Tamseel Shams <m.shams@samsung.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200810030021.45348-1-m.shams@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 551e553f0d upstream.
Commit 7b668c064e ("serial: 8250: Fix max baud limit in generic 8250
port") fixed limits of a baud rate setting for a generic 8250 port.
In other words since that commit the baud rate has been permitted to be
within [uartclk / 16 / UART_DIV_MAX; uartclk / 16], which is absolutely
normal for a standard 8250 UART port. But there are custom 8250 ports,
which provide extended baud rate limits. In particular the Mediatek 8250
port can work with baud rates up to "uartclk" speed.
Normally that and any other peculiarity is supposed to be handled in a
custom set_termios() callback implemented in the vendor-specific
8250-port glue-driver. Currently that is how it's done for the most of
the vendor-specific 8250 ports, but for some reason for Mediatek a
solution has been spread out to both the glue-driver and to the generic
8250-port code. Due to that a bug has been introduced, which permitted the
extended baud rate limit for all even for standard 8250-ports. The bug
has been fixed by the commit 7b668c064e ("serial: 8250: Fix max baud
limit in generic 8250 port") by narrowing the baud rates limit back down to
the normal bounds. Unfortunately by doing so we also broke the
Mediatek-specific extended bauds feature.
A fix of the problem described above is twofold. First since we can't get
back the extended baud rate limits feature to the generic set_termios()
function and that method supports only a standard baud rates range, the
requested baud rate must be locally stored before calling it and then
restored back to the new termios structure after the generic set_termios()
finished its magic business. By doing so we still use the
serial8250_do_set_termios() method to set the LCR/MCR/FCR/etc. registers,
while the extended baud rate setting procedure will be performed later in
the custom Mediatek-specific set_termios() callback. Second since a true
baud rate is now fully calculated in the custom set_termios() method we
need to locally update the port timeout by calling the
uart_update_timeout() function. After the fixes described above are
implemented in the 8250_mtk.c driver, the Mediatek 8250-port should
get back to normally working with extended baud rates.
Link: https://lore.kernel.org/linux-serial/20200701211337.3027448-1-danielwinkler@google.com
Fixes: 7b668c064e ("serial: 8250: Fix max baud limit in generic 8250 port")
Reported-by: Daniel Winkler <danielwinkler@google.com>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: stable <stable@vger.kernel.org>
Tested-by: Claire Chang <tientzu@chromium.org>
Link: https://lore.kernel.org/r/20200714124113.20918-1-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8508f4cba3 ]
Valentine reported seeing:
[ 3.626638] INFO: trying to register non-static key.
[ 3.626639] the code is fine but needs lockdep annotation.
[ 3.626640] turning off the locking correctness validator.
[ 3.626644] CPU: 7 PID: 51 Comm: kworker/7:1 Not tainted 5.7.0-rc2-00115-g8c2e9790f196 #116
[ 3.626646] Hardware name: HiKey960 (DT)
[ 3.626656] Workqueue: events deferred_probe_work_func
[ 3.632476] sd 0:0:0:0: [sda] Optimal transfer size 8192 bytes not a multiple of physical block size (16384 bytes)
[ 3.640220] Call trace:
[ 3.640225] dump_backtrace+0x0/0x1b8
[ 3.640227] show_stack+0x20/0x30
[ 3.640230] dump_stack+0xec/0x158
[ 3.640234] register_lock_class+0x598/0x5c0
[ 3.640235] __lock_acquire+0x80/0x16c0
[ 3.640236] lock_acquire+0xf4/0x4a0
[ 3.640241] _raw_spin_lock_irqsave+0x70/0xa8
[ 3.640245] uart_add_one_port+0x388/0x4b8
[ 3.640248] pl011_register_port+0x70/0xf0
[ 3.640250] pl011_probe+0x184/0x1b8
[ 3.640254] amba_probe+0xdc/0x180
[ 3.640256] really_probe+0xe0/0x338
[ 3.640257] driver_probe_device+0x60/0xf8
[ 3.640259] __device_attach_driver+0x8c/0xd0
[ 3.640260] bus_for_each_drv+0x84/0xd8
[ 3.640261] __device_attach+0xe4/0x140
[ 3.640263] device_initial_probe+0x1c/0x28
[ 3.640265] bus_probe_device+0xa4/0xb0
[ 3.640266] deferred_probe_work_func+0x7c/0xb8
[ 3.640269] process_one_work+0x2c0/0x768
[ 3.640271] worker_thread+0x4c/0x498
[ 3.640272] kthread+0x14c/0x158
[ 3.640275] ret_from_fork+0x10/0x1c
Which seems to be due to the fact that after allocating the uap
structure, nothing initializes the spinlock.
Its a little confusing, as uart_port_spin_lock_init() is one
place where the lock is supposed to be initialized, but it has
an exception for the case where the port is a console.
This makes it seem like a deeper fix is needed to properly
register the console, but I'm not sure what that entails, and
Andy suggested that this approach is less invasive.
Thus, this patch resolves the issue by initializing the spinlock
in the driver, and resolves the resulting warning.
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-serial@vger.kernel.org
Reported-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Reviewed-and-tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lore.kernel.org/r/20200428184050.6501-1-john.stultz@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e00164a0f0 upstream.
err_spi is used when SERIAL_SC16IS7XX_SPI is enabled, so make
the label only available under SERIAL_SC16IS7XX_SPI option.
Otherwise, the below warning appears.
drivers/tty/serial/sc16is7xx.c:1523:1: warning: label ‘err_spi’ defined but not used [-Wunused-label]
err_spi:
^~~~~~~
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Fixes: ac0cdb3d99 ("sc16is7xx: missing unregister/delete driver on error in sc16is7xx_init()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 87c5cbf71e ]
On AR934x this UART is usually not initialized by the bootloader
as it is only used as a secondary serial port while the primary
UART is a newly introduced NS16550-compatible.
In order to make use of the ar933x-uart on AR934x without RTS/CTS
hardware flow control, one needs to set the
UART_CS_{RX,TX}_READY_ORIDE bits as other than on AR933x where this
UART is used as primary/console, the bootloader on AR934x typically
doesn't set those bits.
Setting them explicitely on AR933x should not do any harm, so just
set them unconditionally.
Tested-by: Chuanhong Guo <gch981213@gmail.com>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Link: https://lore.kernel.org/r/20200207095335.GA179836@makrotopia.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 7febbcbc48 upstream.
The commit 54e53b2e80
("tty: serial: 8250: pass IRQ shared flag to UART ports")
nicely explained the problem:
---8<---8<---
On some systems IRQ lines between multiple UARTs might be shared. If so, the
irqflags have to be configured accordingly. The reason is: The 8250 port startup
code performs IRQ tests *before* the IRQ handler for that particular port is
registered. This is performed in serial8250_do_startup(). This function checks
whether IRQF_SHARED is configured and only then disables the IRQ line while
testing.
This test is performed upon each open() of the UART device. Imagine two UARTs
share the same IRQ line: On is already opened and the IRQ is active. When the
second UART is opened, the IRQ line has to be disabled while performing IRQ
tests. Otherwise an IRQ might handler might be invoked, but the IRQ itself
cannot be handled, because the corresponding handler isn't registered,
yet. That's because the 8250 code uses a chain-handler and invokes the
corresponding port's IRQ handling routines himself.
Unfortunately this IRQF_SHARED flag isn't configured for UARTs probed via device
tree even if the IRQs are shared. This way, the actual and shared IRQ line isn't
disabled while performing tests and the kernel correctly detects a spurious
IRQ. So, adding this flag to the DT probe solves the issue.
Note: The UPF_SHARE_IRQ flag is configured unconditionally. Therefore, the
IRQF_SHARED flag can be set unconditionally as well.
Example stack trace by performing `echo 1 > /dev/ttyS2` on a non-patched system:
|irq 85: nobody cared (try booting with the "irqpoll" option)
| [...]
|handlers:
|[<ffff0000080fc628>] irq_default_primary_handler threaded [<ffff00000855fbb8>] serial8250_interrupt
|Disabling IRQ #85
---8<---8<---
But unfortunately didn't fix the root cause. Let's try again here by moving
IRQ flag assignment from serial_link_irq_chain() to serial8250_do_startup().
This should fix the similar issue reported for 8250_pnp case.
Since this change we don't need to have custom solutions in 8250_aspeed_vuart
and 8250_of drivers, thus, drop them.
Fixes: 1c2f04937b ("serial: 8250: add IRQ trigger support")
Reported-by: Li RongQing <lirongqing@baidu.com>
Cc: Kurt Kanzenbach <kurt@linutronix.de>
Cc: Vikram Pandita <vikram.pandita@ti.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Kurt Kanzenbach <kurt@linutronix.de>
Link: https://lore.kernel.org/r/20200211135559.85960-1-andriy.shevchenko@linux.intel.com
[Kurt: Backport to v4.9]
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dc76697d7e upstream.
Unbinding the bcm2835aux UART driver raises the following error if the
maximum number of 8250 UARTs is set to 1 (via the 8250.nr_uarts module
parameter or CONFIG_SERIAL_8250_RUNTIME_UARTS):
(NULL device *): Removing wrong port: a6f80333 != fa20408b
That's because bcm2835aux_serial_probe() retrieves UART line number 1
from the devicetree and stores it in data->uart.port.line, while
serial8250_register_8250_port() instead uses UART line number 0,
which is stored in data->line.
On driver unbind, bcm2835aux_serial_remove() uses data->uart.port.line,
which contains the wrong number. Fix it.
The issue does not occur if the maximum number of 8250 UARTs is >= 2.
Fixes: bdc5f30095 ("serial: bcm2835: add driver for bcm2835-aux-uart")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v4.6+
Cc: Martin Sperl <kernel@martin.sperl.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/912ccf553c5258135c6d7e8f404a101ef320f0f4.1579175223.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 74887542fd upstream.
Per Documentation/DMA-API-HOWTO.txt,
To unmap a scatterlist, just call:
dma_unmap_sg(dev, sglist, nents, direction);
.. note::
The 'nents' argument to the dma_unmap_sg call must be
the _same_ one you passed into the dma_map_sg call,
it should _NOT_ be the 'count' value _returned_ from the
dma_map_sg call.
However in the driver, priv->nent is directly assigned with value
returned from dma_map_sg, and dma_unmap_sg use priv->nent for unmap,
this breaks the API usage.
So introduce a new entry orig_nent to remember 'nents'.
Fixes: da3564ee02 ("pch_uart: add multi-scatter processing")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/1573623259-6339-1-git-send-email-peng.fan@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fb2b90014d upstream.
There seems to be a race condition in tty drivers and I could see on
many boot cycles a NULL pointer dereference as tty_init_dev() tries to
do 'tty->port->itty = tty' even though tty->port is NULL.
'tty->port' will be set by the driver and if the driver has not yet done
it before we open the tty device we can get to this situation. By adding
some extra debug prints, I noticed that:
6.650130: uart_add_one_port
6.663849: register_console
6.664846: tty_open
6.674391: tty_init_dev
6.675456: tty_port_link_device
uart_add_one_port() registers the console, as soon as it registers, the
userspace tries to use it and that leads to tty_open() but
uart_add_one_port() has not yet done tty_port_link_device() and so
tty->port is not yet configured when control reaches tty_init_dev().
Further look into the code and tty_port_link_device() is done by
uart_add_one_port(). After registering the console uart_add_one_port()
will call tty_port_register_device_attr_serdev() and
tty_port_link_device() is called from this.
Call add tty_port_link_device() before uart_configure_port() is done and
add a check in tty_port_link_device() so that it only links the port if
it has not been done yet.
Suggested-by: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191212131602.29504-1-sudipm.mukherjee@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0e4f7f920a upstream.
As the commit 677fe555cb ("serial: imx: Fix recursive locking bug")
has mentioned the uart driver might cause recursive locking between
normal printing and the kernel debugging facilities (e.g. sysrq and
oops). In the commit it gave out suggestion for fixing recursive
locking issue: "The solution is to avoid locking in the sysrq case
and trylock in the oops_in_progress case."
This patch follows the suggestion (also used the exactly same code with
other serial drivers, e.g. amba-pl011.c) to fix the recursive locking
issue, this can avoid stuck caused by deadlock and print out log for
sysrq and oops.
Fixes: 04896a77a9 ("msm_serial: serial driver for MSM7K onboard serial peripheral.")
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Link: https://lore.kernel.org/r/20191127141544.4277-2-leo.yan@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 63fd4b94b9 ]
The ipg clock only needs to be unprepared in case preparing
per clock fails. The ipg clock has already disabled at the point.
Fixes: 1cf93e0d54 ("serial: imx: remove the uart_console() check")
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f6a1964771 upstream.
PL011's ->flush_buffer() implementation releases and reacquires the port
lock. Due to a race condition here, data can end up being added to the
circular buffer but neither being discarded nor being sent out. This
leads to, for example, tcdrain(2) waiting indefinitely.
Process A Process B
uart_flush_buffer()
- acquire lock
- circ_clear
- pl011_flush_buffer()
-- release lock
-- dmaengine_terminate_all()
uart_write()
- acquire lock
- add chars to circ buffer
- start_tx()
-- start DMA
- release lock
-- acquire lock
-- turn off DMA
-- release lock
// Data in circ buffer but DMA is off
According to the comment in the code, the releasing of the lock around
dmaengine_terminate_all() is to avoid a deadlock with the DMA engine
callback. However, since the time this code was written, the DMA engine
API documentation seems to have been clarified to say that
dmaengine_terminate_all() (in the identically implemented but
differently named dmaengine_terminate_async() variant) does not wait for
any running complete callback to be completed and can even be called
from a complete callback. So there is no possibility of deadlock if the
DMA engine driver implements this API correctly.
So we should be able to just remove this release and reacquire of the
lock to prevent the aforementioned race condition.
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191118092547.32135-1-vincent.whitchurch@axis.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b027ce2583 upstream.
hci_qca interfaces to the wcn3990 via a uart_dm on the msm8998 mtp and
Lenovo Miix 630 laptop. As part of initializing the wcn3990, hci_qca
disables flow, configures the uart baudrate, and then reenables flow - at
which point an event is expected to be received over the uart from the
wcn3990. It is observed that this event comes after the baudrate change
but before hci_qca re-enables flow. This is unexpected, and is a result of
msm_reset() being broken.
According to the uart_dm hardware documentation, it is recommended that
automatic hardware flow control be enabled by setting RX_RDY_CTL. Auto
hw flow control will manage RFR based on the configured watermark. When
there is space to receive data, the hw will assert RFR. When the watermark
is hit, the hw will de-assert RFR.
The hardware documentation indicates that RFR can me manually managed via
CR when RX_RDY_CTL is not set. SET_RFR asserts RFR, and RESET_RFR
de-asserts RFR.
msm_reset() is broken because after resetting the hardware, it
unconditionally asserts RFR via SET_RFR. This enables flow regardless of
the current configuration, and would undo a previous flow disable
operation. It should instead de-assert RFR via RESET_RFR to block flow
until the hardware is reconfigured. msm_serial should rely on the client
to specify that flow should be enabled, either via mctrl() or the termios
structure, and only assert RFR in response to those triggers.
Fixes: 04896a77a9 ("msm_serial: serial driver for MSM7K onboard serial peripheral.")
Signed-off-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Andy Gross <agross@kernel.org>
Link: https://lore.kernel.org/r/20191021154616.25457-1-jeffrey.l.hugo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
