Commit Graph

7821 Commits

Author SHA1 Message Date
Tony Lindgren
cc994bb975 serial: 8250: Fix runtime PM for start_tx() for empty buffer
Commit 932d596378 ("serial: 8250: Return early in .start_tx() if there
are no chars to send") caused a regression where the drivers implementing
runtime PM stopped idling. This is because serial8250_rpm_put_tx() is now
unbalanced on early return, it normally gets called at __stop_tx().

Fixes: 932d596378 ("serial: 8250: Return early in .start_tx() if there are no chars to send")
Cc: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20220411111657.16744-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:42:09 +02:00
Johan Hovold
3ee82c6e41 serial: imx: fix overrun interrupts in DMA mode
Commit 76821e222c ("serial: imx: ensure that RX irqs are off if RX is
off") accidentally enabled overrun interrupts unconditionally when
deferring DMA enable until after the receiver has been enabled during
startup.

Fix this by using the DMA-initialised instead of DMA-enabled flag to
determine whether overrun interrupts should be enabled.

Note that overrun interrupts are already accounted for in
imx_uart_clear_rx_errors() when using DMA since commit 41d98b5da9
("serial: imx-serial - update RX error counters when DMA is used").

Fixes: 76821e222c ("serial: imx: ensure that RX irqs are off if RX is off")
Cc: stable@vger.kernel.org      # 4.17
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20220411081957.7846-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:41:58 +02:00
Lino Sanfilippo
0e4deb56b0 serial: amba-pl011: do not time out prematurely when draining tx fifo
The current timeout for draining the tx fifo in RS485 mode is calculated by
multiplying the time it takes to transmit one character (with the given
baud rate) with the maximal number of characters in the tx queue.

This timeout is too short for two reasons:
First when calculating the time to transmit one character integer division
is used which may round down the result in case of a remainder of the
division.

Fix this by rounding up the division result.

Second the hardware may need additional time (e.g for first putting the
characters from the fifo into the shift register) before the characters are
actually put onto the wire.

To be on the safe side double the current maximum number of iterations
that are used to wait for the queue draining.

Fixes: 8d47923772 ("serial: amba-pl011: add RS485 support")
Cc: stable@vger.kernel.org
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220408233503.7251-1-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:41:56 +02:00
Sherry Sun
f398e0aa32 tty: serial: fsl_lpuart: fix potential bug when using both of_alias_get_id and ida_simple_get
Now fsl_lpuart driver use both of_alias_get_id() and ida_simple_get() in
.probe(), which has the potential bug. For example, when remove the
lpuart7 alias in dts, of_alias_get_id() will return error, then call
ida_simple_get() to allocate the id 0 for lpuart7, this may confilct
with the lpuart4 which has alias 0.

    aliases {
	...
        serial0 = &lpuart4;
        serial1 = &lpuart5;
        serial2 = &lpuart6;
        serial3 = &lpuart7;
    }

So remove the ida_simple_get() in .probe(), return an error directly
when calling of_alias_get_id() fails, which is consistent with other
uart drivers behavior.

Fixes: 3bc3206e1c ("serial: fsl_lpuart: Remove the alias node dependence")
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20220321112211.8895-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:41:12 +02:00
Al Cooper
18c9d4a3c2 serial: When UART is suspended, set RTS to false
When flow control is enabled, the UART should set RTS to false
during suspend to stop incoming data. Currently, the suspend
routine sets the mctrl register in the uart to zero, but leaves
the shadow version in the uart_port struct alone so that resume
can restore it. This causes a problem later in suspend when
serial8250_do_shutdown() is called which uses the shadow mctrl
register to clear some additional bits but ends up restoring RTS.
The solution is to clear RTS from the shadow version before
serial8250_do_shutdown() is called and restore it after.

Signed-off-by: Al Cooper <alcooperx@comcast.net>
Link: https://lore.kernel.org/r/20220324145620.41573-1-alcooperx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:40:05 +02:00
Eric Tremblay
bec1f1b66a serial: 8250: add compatible for fsl,16550-FIFO64
Signed-off-by: Eric Tremblay <etremblay@distech-controls.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220330104642.229507-4-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:37:27 +02:00
Eric Tremblay
296385fe12 serial: 8250: Add UART_CAP_NOTEMT on PORT_16550A_FSL64
The Freescale variant of the 16550A doesn't have an interrupt on TEMT
available when using the FIFO mode.

Signed-off-by: Eric Tremblay <etremblay@distech-controls.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220330104642.229507-3-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:37:27 +02:00
Eric Tremblay
f6f586102a serial: 8250: Handle UART without interrupt on TEMT using em485
Introduce the UART_CAP_NOTEMT capability. The capability indicates that
the UART doesn't have an interrupt available on TEMT.

In the case where the device does not support it, we calculate the
maximum time it could take for the transmitter to empty the
shift register. When we get in the situation where we get the
THRE interrupt, we check if the TEMT bit is set. If it's not, we start
the a timer and recall __stop_tx() after the delay.

The transmit sequence is a bit modified when the capability is set. The
new timer is used between the last interrupt(THRE) and a potential
stop_tx timer.

Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com>
[moved to use added UART_CAP_TEMT]
Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
[moved to use added UART_CAP_NOTEMT, improve timeout]
Signed-off-by: Eric Tremblay <etremblay@distech-controls.com>
[rebased to v5.17, making use of tty_get_frame_size]
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220330104642.229507-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:37:27 +02:00
Miaoqian Lin
0e0fd55719 serial: 8250_aspeed_vuart: Fix potential NULL dereference in aspeed_vuart_probe
platform_get_resource() may fail and return NULL, so we should
better check it's return value to avoid a NULL pointer dereference.

Fixes: 54da3e381c ("serial: 8250_aspeed_vuart: use UPF_IOREMAP to set up register mapping")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220404143842.16960-1-linmq006@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:31:29 +02:00
Lino Sanfilippo
60efd05139 serial: atmel: remove redundant assignment in rs485_config
In uart_set_rs485_config() the serial core already assigns the passed
serial_rs485 struct to the uart port.

So remove the assignment from the drivers rs485_config() function to avoid
redundancy.

Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-10-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:30:22 +02:00
Lino Sanfilippo
e5d4d733fc serial: fsl_lpuart: remove redundant code in rs485_config functions
In uart_set_rs485_config() the serial core already ensures that only one of
both options RTS on send or RTS after send is set. It also assigns the
passed serial_rs485 struct to the uart port.

So remove the check and the assignment from the drivers rs485_config()
function to avoid redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-9-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:30:22 +02:00
Lino Sanfilippo
9151624601 serial: imx: remove redundant assignment in rs485_config
In uart_set_rs485_config() the serial core already assigns the passed
serial_rs485 struct to the uart port.

So remove the assignment in the drivers rs485_config() function to avoid
reduncancy.

Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-8-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:30:22 +02:00
Lino Sanfilippo
e767aa14f7 serial: max310: remove redundant memset in rs485_config
In uart_set_rs485_config() the serial core already nullifies the padding
field of the passed serial_rs485 struct before returning it to userspace.

Doing the same in the drivers rs485_config() function is redundant, so
remove the concerning memset in this function.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-7-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:30:22 +02:00
Lino Sanfilippo
d84b01cd04 serial: omap: remove redundant code in rs485_config
In uart_set_rs485_config() the serial core already clamps the RTS delays.
It also assigns the passed serial_rs485 struct to the uart port.

So remove these tasks from the drivers rs485_config() function to avoid
redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-6-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:30:22 +02:00
Lino Sanfilippo
afea2a93c2 serial: sc16is7xx: remove redundant check in rs485_config
In uart_set_rs485_config() the serial core already ensures that only one of
both options RTS on send or RTS after send is set.

So remove this check from the drivers rs485_config() function to avoid
redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-5-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:30:22 +02:00
Lino Sanfilippo
f633eb294a serial: stm32: remove redundant code in rs485_config
In uart_set_rs485_config() the serial core already ensures that only one of
both options RTS on send or RTS after send is set. It also assigns the
passed serial_rs485 struct to the uart port.

So remove the check and the assignment from the drivers rs485_config()
function to avoid redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-4-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:30:21 +02:00
Lino Sanfilippo
a9efa45248 serial: amba-pl011: remove redundant code in rs485_config
In uart_set_rs485_config() the serial core already

- ensures that only one of both options RTS on send or RTS after send is
  set

- nullifies the padding field of the passed serial_rs485 struct

- clamps the RTS delays

- assigns the passed serial_rs485 struct to the uart port

So remove these tasks from the code of the drivers rs485_config() function
to avoid redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-3-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:30:21 +02:00
Lino Sanfilippo
0ed12afa56 serial: core: move RS485 configuration tasks from drivers into core
Several drivers that support setting the RS485 configuration via userspace
implement one or more of the following tasks:

- in case of an invalid RTS configuration (both RTS after send and RTS on
  send set or both unset) fall back to enable RTS on send and disable RTS
  after send

- nullify the padding field of the returned serial_rs485 struct

- copy the configuration into the uart port struct

- limit RTS delays to 100 ms

Move these tasks into the serial core to make them generic and to provide
a consistent behaviour among all drivers.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-2-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:30:21 +02:00
Yu Tu
368ab68b18 tty: serial: meson: Use DIV_ROUND_CLOSEST to calculate baud rates
Due to chip process differences, chip designers recommend using baud
rates as close to and larger as possible in order to reduce clock
errors.

Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20220407081355.13602-2-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:28:10 +02:00
Maciej W. Rozycki
e0239ba3ff serial: 8250: Report which option to enable for blacklisted PCI devices
Provide information in the kernel log as to what configuration option to
enable for PCI UART devices that have been blacklisted in the generic
PCI 8250 UART driver and which have a dedicated driver available to
handle that has been disabled.  The rationale is there is no easy way
for the user to map a specific PCI vendor:device pair to an individual
dedicated driver while the generic driver has this information readily
available and it will likely be confusing that the generic driver does
not register such a port.

This is unlike usual drivers, such as drivers/net/ethernet/3com/3c59x.c
which handles all the hardware family members regardless of differences
between them, and following an existing example where a serio driver
provides suggestions as to the correct configuration options to use:

psmouse serio1: synaptics: The touchpad can support a better bus than the too old PS/2 protocol. Make sure MOUSE_PS2_SYNAPTICS_SMBUS and RMI4_SMB are enabled to get a better touchpad experience.

A message is then printed like:

serial 0000:04:00.3: ignoring port, enable SERIAL_8250_PERICOM to handle

when an affected device is encountered and the generic driver rejects it.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2203310054120.44113@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:15:19 +02:00
Daniel Gibson
65a8b28702 tty: n_tty: Restore EOF push handling behavior
TTYs in ICANON mode have a special case that allows "pushing" a line
without a regular EOL character (like newline), by using EOF (the EOT
character - ASCII 0x4) as a pseudo-EOL. It is silently discarded, so
the reader of the PTS will receive the line *without* EOF or any other
terminating character.

This special case has an edge case: What happens if the readers buffer
is the same size as the line (without EOF)? Will they be able to tell
if the whole line is received, i.e. if the next read() will return more
of the same line or the next line?

There are two possibilities,  that both have (dis)advantages:

1. The next read() returns 0. FreeBSD (13.0) and OSX (10.11) do this.
   Advantage: The reader can interpret this as "the line is over".
   Disadvantage: read() returning 0 means EOF, the reader could also
   interpret it as "there's no more data" and stop reading or even
   close the PT.

2. The next read() returns the next line, the EOF is silently discarded.
   Solaris (or at least OpenIndiana 2021.10) does this, Linux has done
   do this since commit 40d5e0905a ("n_tty: Fix EOF push handling");
   this behavior was recently broken by commit 3593030761 ("tty:
   n_tty: do not look ahead for EOL character past the end of the buffer").
   Advantage: read() won't return 0 (EOF), reader less likely to be
   confused (and things like `while(read(..)>0)` don't break)
   Disadvantage: The reader can't really know if the read() continues
   the last line (that filled the whole read buffer) or starts a
   new line.

As both options are defensible (and are used by other Unix-likes), it's
best to stick to the "old" behavior since "n_tty: Fix EOF push handling"
of 2013, i.e. silently discard that EOF.

This patch - that I actually got from Linus for testing and only
modified slightly - restores that behavior by skipping an EOF
character if it's the next character after reading is done.

Based on a patch from Linus Torvalds.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215611
Fixes: 3593030761 ("tty: n_tty: do not look ahead for EOL character past the end of the buffer")
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Reviewed-and-tested-by: Daniel Gibson <daniel@gibson.sh>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Daniel Gibson <daniel@gibson.sh>
Link: https://lore.kernel.org/r/20220329235810.452513-2-daniel@gibson.sh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:11:37 +02:00
Phil Edworthy
857f971328 serial: 8250: Make SERIAL_8250_EM available for arm64 systems
This is needed for the Renesas RZ/V2M (r9a09g011) SoC.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220330154024.112270-6-phil.edworthy@renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:11:11 +02:00
Miaoqian Lin
bcea0f547e tty: serial: owl: Fix missing clk_disable_unprepare() in owl_uart_probe
Fix the missing clk_disable_unprepare() before return
from owl_uart_probe() in the error handling case.

Fixes: abf42d2f33 ("tty: serial: owl: add "much needed" clk_prepare_enable()")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220307105135.11698-1-linmq006@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:08:12 +02:00
Jaewon Kim
e73b5c7f3d tty: serial: samsung: add spin_lock for interrupt and console_write
The console_write and IRQ handler can run concurrently.
Problems may occurs console_write is continuously executed while
the IRQ handler is running.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
Link: https://lore.kernel.org/r/20220407071619.102249-2-jaewon02.kim@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:42:46 +02:00
Huang Guobin
ee157a79e7 tty: Fix a possible resource leak in icom_probe
When pci_read_config_dword failed, call pci_release_regions() and
pci_disable_device() to recycle the resource previously allocated.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Huang Guobin <huangguobin4@huawei.com>
Link: https://lore.kernel.org/r/20220331091005.3290753-1-huangguobin4@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:42:40 +02:00
Christophe Leroy
570f749f4d tty: serial: Prepare cleanup of powerpc's asm/prom.h
powerpc's asm/prom.h brings some headers that it doesn't
need itself.

In order to clean it up, first add missing headers in
users of asm/prom.h

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/49fc0d4b6446da630b1e9f29c4bab38f8ed087bf.1648833419.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:42:29 +02:00
Christophe Leroy
8fbb3fc9c4 tty: hvc: Prepare cleanup of powerpc's asm/prom.h
powerpc's asm/prom.h brings some headers that it doesn't
need itself.

In order to clean it up, first add missing headers in
users of asm/prom.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/8b3dbd25bbeb7949e1b0a2170fee7b9cc5a6f806.1648833418.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:42:26 +02:00
Wang Weiyang
507b05063d tty: goldfish: Use tty_port_destroy() to destroy port
In goldfish_tty_probe(), the port initialized through tty_port_init()
should be destroyed in error paths.In goldfish_tty_remove(), qtty->port
also should be destroyed or else might leak resources.

Fix the above by calling tty_port_destroy().

Fixes: 666b7793d4 ("goldfish: tty driver")
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Wang Weiyang <wangweiyang2@huawei.com>
Link: https://lore.kernel.org/r/20220328115844.86032-1-wangweiyang2@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:42:21 +02:00
Daniel Starke
ff9166c623 tty: n_gsm: fix incorrect UA handling
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.4.2 states that any received unnumbered
acknowledgment (UA) with its poll/final (PF) bit set to 0 shall be
discarded. Currently, all UA frame are handled in the same way regardless
of the PF bit. This does not comply with the standard.
Remove the UA case in gsm_queue() to process only UA frames with PF bit set
to 1 to abide the standard.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-20-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:05 +02:00
Daniel Starke
73029a4d71 tty: n_gsm: fix reset fifo race condition
gsmtty_write() and gsm_dlci_data_output() properly guard the fifo access.
However, gsm_dlci_close() and gsmtty_flush_buffer() modifies the fifo but
do not guard this.
Add a guard here to prevent race conditions on parallel writes to the fifo.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-17-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:05 +02:00
Daniel Starke
1adf6fee58 tty: n_gsm: fix missing tty wakeup in convergence layer type 2
gsm_control_modem() informs the virtual tty that more data can be written
after receiving a control signal octet via modem status command (MSC).
However, gsm_dlci_data() fails to do the same after receiving a control
signal octet from the convergence layer type 2 header.
Add tty_wakeup() in gsm_dlci_data() for convergence layer type 2 to fix
this.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-14-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:05 +02:00
Daniel Starke
317f86af7f tty: n_gsm: fix wrong signal octets encoding in MSC
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. The value of the modem status command (MSC) frame
contains an address field, control signal and optional break signal octet.
The address field is encoded as described in chapter 5.2.1.2 with only one
octet (may be extended to more in future versions of the standard). Whereas
the control signal and break signal octet are always one byte each. This is
strange at first glance as it makes the EA bit redundant. However, the same
two octets are also encoded as header in convergence layer type 2 as
described in chapter 5.5.2. No header length field is given and the only
way to test if there is an optional break signal octet is via the EA flag
which extends the control signal octet with a break signal octet. Now it
becomes obvious how the EA bit for those two octets shall be encoded in the
MSC frame. The current implementation treats the signal octet different for
MSC frame and convergence layer type 2 header even though the standard
describes it for both in the same way.
Use the EA bit to encode the signal octets not only in the convergence
layer type 2 header but also in the MSC frame in the same way with either
1 or 2 bytes in case of an optional break signal. Adjust the receiving path
accordingly in gsm_control_modem().

Fixes: 3ac06b9056 ("tty: n_gsm: Fix for modems with brk in modem status control")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-13-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:05 +02:00
Daniel Starke
398867f59f tty: n_gsm: fix wrong command frame length field encoding
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.6.1 states that each command frame shall
be made up from type, length and value. Looking for example in chapter
5.4.6.3.5 at the description for the encoding of a flow control on command
it becomes obvious, that the type and length field is always present
whereas the value may be zero bytes long. The current implementation omits
the length field if the value is not present. This is wrong.
Correct this by always sending the length in gsm_control_transmit().
So far only the modem status command (MSC) has included a value and encoded
its length directly. Therefore, also change gsmtty_modem_update().

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-12-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:05 +02:00
Daniel Starke
d0bcdffcad tty: n_gsm: fix wrong command retry handling
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.7.3 states that the valid range for the
maximum number of retransmissions (N2) is from 0 to 255 (both including).
gsm_config() fails to limit this range correctly. Furthermore,
gsm_control_retransmit() handles this number incorrectly by performing
N2 - 1 retransmission attempts. Setting N2 to zero results in more than 255
retransmission attempts.
Fix the range check in gsm_config() and the value handling in
gsm_control_send() and gsm_control_retransmit() to comply with 3GPP 27.010.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-11-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Daniel Starke
17eac65202 tty: n_gsm: fix missing explicit ldisc flush
In gsm_cleanup_mux() the muxer is closed down and all queues are removed.
However, removing the queues is done without explicit control of the
underlying buffers. Flush those before freeing up our queues to ensure
that all outgoing queues are cleared consistently. Otherwise, a new mux
connection establishment attempt may time out while the underlying tty is
still busy sending out the remaining data from the previous connection.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-10-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Daniel Starke
deefc58baf tty: n_gsm: fix wrong DLCI release order
The current DLCI release order starts with the control channel followed by
the user channels. Reverse this order to keep the control channel open
until all user channels have been released.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-9-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Daniel Starke
535bf600de tty: n_gsm: fix insufficient txframe size
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.7.2 states that the maximum frame size
(N1) refers to the length of the information field (i.e. user payload).
However, 'txframe' stores the whole frame including frame header, checksum
and start/end flags. We also need to consider the byte stuffing overhead.
Define constant for the protocol overhead and adjust the 'txframe' size
calculation accordingly to reserve enough space for a complete mux frame
including byte stuffing for advanced option mode. Note that no byte
stuffing is applied to the start and end flag.
Also use MAX_MTU instead of MAX_MRU as this buffer is used for data
transmission.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-8-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Daniel Starke
a24b4b2f66 tty: n_gsm: fix malformed counter for out of frame data
The gsm_mux field 'malformed' represents the number of malformed frames
received. However, gsm1_receive() also increases this counter for any out
of frame byte.
Fix this by ignoring out of frame data for the malformed counter.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-7-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Daniel Starke
7a0e4b1733 tty: n_gsm: fix frame reception handling
The frame checksum (FCS) is currently handled in gsm_queue() after
reception of a frame. However, this breaks layering. A workaround with
'received_fcs' was implemented so far.
Furthermore, frames are handled as such even if no end flag was received.
Move FCS calculation from gsm_queue() to gsm0_receive() and gsm1_receive().
Also delay gsm_queue() call there until a full frame was received to fix
both points.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-6-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Daniel Starke
06d5afd4d6 tty: n_gsm: fix wrong signal octet encoding in convergence layer type 2
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.5.2 describes that the signal octet in
convergence layer type 2 can be either one or two bytes. The length is
encoded in the EA bit. This is set 1 for the last byte in the sequence.
gsmtty_modem_update() handles this correctly but gsm_dlci_data_output()
fails to set EA to 1. There is no case in which we encode two signal octets
as there is no case in which we send out a break signal.
Therefore, always set the EA bit to 1 for the signal octet to fix this.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-5-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Daniel Starke
284260f278 tty: n_gsm: fix mux cleanup after unregister tty device
Internally, we manage the alive state of the mux channels and mux itself
with the field member 'dead'. This makes it possible to notify the user
if the accessed underlying link is already gone. On the other hand,
however, removing the virtual ttys before terminating the channels may
result in peer messages being received without any internal target. Move
the mux cleanup procedure from gsmld_detach_gsm() to gsmld_close() to fix
this by keeping the virtual ttys open until the mux has been cleaned up.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-4-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Daniel Starke
1ec92e9742 tty: n_gsm: fix decoupled mux resource
The active mux instances are managed in the gsm_mux array and via mux_get()
and mux_put() functions separately. This gives a very loose coupling
between the actual instance and the gsm_mux array which manages it. It also
results in unnecessary lockings which makes it prone to failures. And it
creates a race condition if more than the maximum number of mux instances
are requested while the user changes the parameters of an active instance.
The user may loose ownership of the current mux instance in this case.
Fix this by moving the gsm_mux array handling to the mux allocation and
deallocation functions.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-3-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Daniel Starke
aa371e96f0 tty: n_gsm: fix restart handling via CLD command
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.8.2 states that both sides will revert to
the non-multiplexed mode via a close-down message (CLD). The usual program
flow is as following:
- start multiplex mode by sending AT+CMUX to the mobile
- establish the control channel (DLCI 0)
- establish user channels (DLCI >0)
- terminate user channels
- send close-down message (CLD)
- revert to AT protocol (i.e. leave multiplexed mode)

The AT protocol is out of scope of the n_gsm driver. However,
gsm_disconnect() sends CLD if gsm_config() detects that the requested
parameters require the mux protocol to restart. The next immediate action
is to start the mux protocol by opening DLCI 0 again. Any responder side
which handles CLD commands correctly forces us to fail at this point
because AT+CMUX needs to be sent to the mobile to start the mux again.
Therefore, remove the CLD command in this phase and keep both sides in
multiplexed mode.
Remove the gsm_disconnect() function as it become unnecessary and merge the
remaining parts into gsm_cleanup_mux() to handle the termination order and
locking correctly.

Fixes: 71e0779153 ("tty: n_gsm: do not send/receive in ldisc close path")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Daniel Starke
11451693e4 tty: n_gsm: fix missing mux reset on config change at responder
Currently, only the initiator resets the mux protocol if the user requests
new parameters that are incompatible to those of the current connection.
The responder also needs to reset the multiplexer if the new parameter set
requires this. Otherwise, we end up with an inconsistent parameter set
between initiator and responder.
Revert the old behavior to inform the peer upon an incompatible parameter
set change from the user on the responder side by re-establishing the mux
protocol in such case.

Fixes: 509067bbd2 ("tty: n_gsm: Delete gsm_disconnect when config requester")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220414094225.4527-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 08:36:04 +02:00
Jiri Slaby
9c3a431a48 tty: serial: altera: use altera_jtaguart_stop_tx()
altera_jtaguart_tx_chars() duplicates what altera_jtaguart_stop_tx()
already does. So instead of the duplication, call the helper instead.

Not only it makes the code cleaner, but it also says what the "if"
really does.

Cc: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411104506.8990-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-14 18:27:18 +02:00
Jiri Slaby
d9b80d07db tty: serial: owl-uart, send x_char even if stopped
Flow control characters should be sent even if the TX is stopped. So fix
owl-uart to behave the same as other drivers.

This unification also allows the use of the TX helper in the future.

Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411104506.8990-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-14 18:27:18 +02:00
Jiri Slaby
83ead21929 tty: serial: mpc52xx_uart: remove double ifdeffery
The code now contains:
 #ifdef CONFIG_PPC_MPC512x
 ...
 #endif

 #ifdef CONFIG_PPC_MPC512x
 ...
 #endif

So remove the endif+ifdef from the middle, provided it's about the same
define.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411104506.8990-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-14 18:27:18 +02:00
Zheyu Ma
689ca31c54 tty: synclink_gt: Fix null-pointer-dereference in slgt_clean()
When the driver fails at alloc_hdlcdev(), and then we remove the driver
module, we will get the following splat:

[   25.065966] general protection fault, probably for non-canonical address 0xdffffc0000000182: 0000 [#1] PREEMPT SMP KASAN PTI
[   25.066914] KASAN: null-ptr-deref in range [0x0000000000000c10-0x0000000000000c17]
[   25.069262] RIP: 0010:detach_hdlc_protocol+0x2a/0x3e0
[   25.077709] Call Trace:
[   25.077924]  <TASK>
[   25.078108]  unregister_hdlc_device+0x16/0x30
[   25.078481]  slgt_cleanup+0x157/0x9f0 [synclink_gt]

Fix this by checking whether the 'info->netdev' is a null pointer first.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Link: https://lore.kernel.org/r/20220410114814.3920474-1-zheyuma97@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-14 18:26:30 +02:00
Laurent Vivier
2e2ac4a332 tty: goldfish: Introduce gf_ioread32()/gf_iowrite32()
The goldfish TTY device was clearly defined as having little-endian
registers, but the switch to __raw_{read,write}l(() broke its driver
when running on big-endian kernels (if anyone ever tried this).

The m68k qemu implementation got this wrong, and assumed native-endian
registers.  While this is a bug in qemu, it is probably impossible to
fix that since there is no way of knowing which other operating systems
have started relying on that bug over the years.

Hence revert commit da31de35cd ("tty: goldfish: use
__raw_writel()/__raw_readl()", and define gf_ioread32()/gf_iowrite32()
to be able to use accessors defined by the architecture.

Cc: stable@vger.kernel.org # v5.11+
Fixes: da31de35cd ("tty: goldfish: use __raw_writel()/__raw_readl()")
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Link: https://lore.kernel.org/r/20220406201523.243733-2-laurent@vivier.eu
[geert: Add rationale based on Arnd's comments]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2022-04-11 11:48:01 +02:00
Arnd Bergmann
fba2689ee7 Merge branch 'remove-h8300' of git://git.infradead.org/users/hch/misc into asm-generic
* 'remove-h8300' of git://git.infradead.org/users/hch/misc:
  remove the h8300 architecture

This is clearly the least actively maintained architecture we have at
the moment, and probably the least useful. It is now the only one that
does not support MMUs at all, and most of the boards only support 4MB
of RAM, out of which the defconfig kernel needs more than half just
for .text/.data.

Guenter Roeck did the original patch to remove the architecture in 2013
after it had already been obsolete for a while, and Yoshinori Sato brought
it back in a much more modern form in 2015. Looking at the git history
since the reinstantiation, it's clear that almost all commits in the tree
are build fixes or cross-architecture cleanups:

$ git log --no-merges --format=%an v4.5.. arch/h8300/  | sort | uniq
-c | sort -rn | head -n 12
     25 Masahiro Yamada
     18 Christoph Hellwig
     14 Mike Rapoport
      9 Arnd Bergmann
      8 Mark Rutland
      7 Peter Zijlstra
      6 Kees Cook
      6 Ingo Molnar
      6 Al Viro
      5 Randy Dunlap
      4 Yury Norov

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-04-04 14:42:49 +02:00