Pull tty/serial fixes from Greg KH:
"Here are some small TTY and Serial driver fixes for 5.16-rc4 to
resolve a number of reported problems.
They include:
- liteuart serial driver fixes
- 8250_pci serial driver fixes for pericom devices
- 8250 RTS line control fix while in RS-485 mode
- tegra serial driver fix
- msm_serial driver fix
- pl011 serial driver new id
- fsl_lpuart revert of broken change
- 8250_bcm7271 serial driver fix
- MAINTAINERS file update for rpmsg tty driver that came in 5.16-rc1
- vgacon fix for reported problem
All of these, except for the 8250_bcm7271 fix have been in linux-next
with no reported problem. The 8250_bcm7271 fix was added to the tree
on Friday so no chance to be linux-next yet. But it should be fine as
the affected developers submitted it"
* tag 'tty-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: 8250_bcm7271: UART errors after resuming from S2
serial: 8250_pci: rewrite pericom_do_set_divisor()
serial: 8250_pci: Fix ACCES entries in pci_serial_quirks array
serial: 8250: Fix RTS modem control while in rs485 mode
Revert "tty: serial: fsl_lpuart: drop earlycon entry for i.MX8QXP"
serial: tegra: Change lower tolerance baud rate limit for tegra20 and tegra30
serial: liteuart: relax compile-test dependencies
serial: liteuart: fix minor-number leak on probe errors
serial: liteuart: fix use-after-free and memleak on unbind
serial: liteuart: Fix NULL pointer dereference in ->remove()
vgacon: Propagate console boot parameters before calling `vc_resize'
tty: serial: msm_serial: Deactivate RX DMA for polling support
serial: pl011: Add ACPI SBSA UART match id
serial: core: fix transmit-buffer reset and memleak
MAINTAINERS: Add rpmsg tty driver maintainer
There is a small window in time during resume where the hardware
flow control signal RTS can be asserted (which allows a sender to
resume sending data to the UART) but the baud rate has not yet
been restored. This will cause corrupted data and FRAMING, OVERRUN
and BREAK errors. This is happening because the MCTRL register is
shadowed in uart_port struct and is later used during resume to set
the MCTRL register during both serial8250_do_startup() and
uart_resume_port(). Unfortunately, serial8250_do_startup()
happens before the UART baud rate is restored. The fix is to clear
the shadowed mctrl value at the end of suspend and restore it at the
end of resume.
Fixes: 41a469482d ("serial: 8250: Add new 8250-core based Broadcom STB driver")
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Link: https://lore.kernel.org/r/20211201201402.47446-1-alcooperx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Have pericom_do_set_divisor() use the uartclk instead of a hard coded
value to work with different speed crystals. Tested with 14.7456 and 24
MHz crystals.
Have pericom_do_set_divisor() always calculate the divisor rather than
call serial8250_do_set_divisor() for rates below baud_base.
Do not write registers or call serial8250_do_set_divisor() if valid
divisors could not be found.
Fixes: 6bf4e42f1d ("serial: 8250: Add support for higher baud rates to Pericom chips")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jay Dolan <jay.dolan@accesio.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211122120604.3909-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit f45709df77 ("serial: 8250: Don't touch RTS modem control while
in rs485 mode") sought to prevent user space from interfering with rs485
communication by ignoring a TIOCMSET ioctl() which changes RTS polarity.
It did so in serial8250_do_set_mctrl(), which turns out to be too deep
in the call stack: When a uart_port is opened, RTS polarity is set by
the rs485-aware function uart_port_dtr_rts(). It calls down to
serial8250_do_set_mctrl() and that particular RTS polarity change should
*not* be ignored.
The user-visible result is that on 8250_omap ports which use rs485 with
inverse polarity (RTS bit in MCR register is 1 to receive, 0 to send),
a newly opened port initially sets up RTS for sending instead of
receiving. That's because omap_8250_startup() sets the cached value
up->mcr to 0 and omap_8250_restore_regs() subsequently writes it to the
MCR register. Due to the commit, serial8250_do_set_mctrl() preserves
that incorrect register value:
do_sys_openat2
do_filp_open
path_openat
vfs_open
do_dentry_open
chrdev_open
tty_open
uart_open
tty_port_open
uart_port_activate
uart_startup
uart_port_startup
serial8250_startup
omap_8250_startup # up->mcr = 0
uart_change_speed
serial8250_set_termios
omap_8250_set_termios
omap_8250_restore_regs
serial8250_out_MCR # up->mcr written
tty_port_block_til_ready
uart_dtr_rts
uart_port_dtr_rts
serial8250_set_mctrl
omap8250_set_mctrl
serial8250_do_set_mctrl # mcr[1] = 1 ignored
Fix by intercepting RTS changes from user space in uart_tiocmset()
instead.
Link: https://lore.kernel.org/linux-serial/20211027111644.1996921-1-baocheng.su@siemens.com/
Fixes: f45709df77 ("serial: 8250: Don't touch RTS modem control while in rs485 mode")
Cc: Chao Zeng <chao.zeng@siemens.com>
Cc: stable@vger.kernel.org # v5.7+
Reported-by: Su Bao Cheng <baocheng.su@siemens.com>
Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Tested-by: Su Bao Cheng <baocheng.su@siemens.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/21170e622a1aaf842a50b32146008b5374b3dd1d.1637596432.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert commit b4b844930f ("tty: serial: fsl_lpuart: drop earlycon entry
for i.MX8QXP"), because this breaks earlycon support on imx8qm/imx8qxp.
While it is true that for earlycon there is no difference between
i.MX8QXP and i.MX7ULP (for now at least), there are differences
regarding clocks and fixups for wakeup support. For that reason it was
deemed unacceptable to add the imx7ulp compatible to device tree in
order to get earlycon working again.
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Link: https://lore.kernel.org/r/20211124073109.805088-1-alexander.stein@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current implementation uses 0 as lower limit for the baud rate
tolerance for tegra20 and tegra30 chips which causes isses on UART
initialization as soon as baud rate clock is lower than required even
when within the standard UART tolerance of +/- 4%.
This fix aligns the implementation with the initial commit description
of +/- 4% tolerance for tegra chips other than tegra186 and
tegra194.
Fixes: d781ec21ba ("serial: tegra: report clk rate errors")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Patrik John <patrik.john@u-blox.com>
Link: https://lore.kernel.org/r/sig.19614244f8.20211123132737.88341-1-patrik.john@u-blox.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The LITEX symbol is neither a build or runtime dependency for the
liteuart serial driver.
LITEX is selected by the "LiteX SoC Controller" driver, which does a
probe-time register-access sanity check and panics if the SoC has not
been configured correctly. That driver's Kconfig entry asserts that any
LiteX driver using the LiteX register accessors should depend on LITEX,
but currently only the serial driver complies.
Relax this LITEX "dependency" in order to make it easier to compile test
the driver.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211117100512.5058-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The CONSOLE_POLLING mode is used for tools like k(g)db. In this kind of
setup, it is often sharing a serial device with the normal system console.
This is usually no problem because the polling helpers can consume input
values directly (when in kgdb context) and the normal Linux handlers can
only consume new input values after kgdb switched back.
This is not true anymore when RX DMA is enabled for UARTDM controllers.
Single input values can no longer be received correctly. Instead following
seems to happen:
* on 1. input, some old input is read (continuously)
* on 2. input, two old inputs are read (continuously)
* on 3. input, three old input values are read (continuously)
* on 4. input, 4 previous inputs are received
This repeats then for each group of 4 input values.
This behavior changes slightly depending on what state the controller was
when the first input was received. But this makes working with kgdb
basically impossible because control messages are always corrupted when
kgdboc tries to parse them.
RX DMA should therefore be off when CONSOLE_POLLING is enabled to avoid
these kind of problems. No such problem was noticed for TX DMA.
Fixes: 9969394501 ("tty: serial: msm: Add RX DMA support")
Cc: stable@vger.kernel.org
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Link: https://lore.kernel.org/r/20211113121050.7266-1-sven@narfation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The document 'ACPI for Arm Components 1.0' defines the following
_HID mappings:
-'Prime cell UART (PL011)': ARMH0011
-'SBSA UART': ARMHB000
Use the sbsa-uart driver when a device is described with
the 'ARMHB000' _HID.
Note:
PL011 devices currently use the sbsa-uart driver instead of the
uart-pl011 driver. Indeed, PL011 devices are not bound to a clock
in ACPI. It is not possible to change their baudrate.
Cc: <stable@vger.kernel.org>
Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
Link: https://lore.kernel.org/r/20211109172248.19061-1-Pierre.Gondois@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 761ed4a945 ("tty: serial_core: convert uart_close to use
tty_port_close") converted serial core to use tty_port_close() but
failed to notice that the transmit buffer still needs to be freed on
final close.
Not freeing the transmit buffer means that the buffer is no longer
cleared on next open so that any ioctl() waiting for the buffer to drain
might wait indefinitely (e.g. on termios changes) or that stale data can
end up being transmitted in case tx is restarted.
Furthermore, the buffer of any port that has been opened would leak on
driver unbind.
Note that the port lock is held when clearing the buffer pointer due to
the ldisc race worked around by commit a5ba1d95e4 ("uart: fix race
between uart_put_char() and uart_shutdown()").
Also note that the tty-port shutdown() callback is not called for
console ports so it is not strictly necessary to free the buffer page
after releasing the lock (cf. d72402145a ("tty/serial: do not free
trasnmit buffer page under port lock")).
Link: https://lore.kernel.org/r/319321886d97c456203d5c6a576a5480d07c3478.1635781688.git.baruch@tkos.co.il
Fixes: 761ed4a945 ("tty: serial_core: convert uart_close to use tty_port_close")
Cc: stable@vger.kernel.org # 4.9
Cc: Rob Herring <robh@kernel.org>
Reported-by: Baruch Siach <baruch@tkos.co.il>
Tested-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211108085431.12637-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull tty / serial driver updates from Greg KH:
"Here is the big set of tty and serial driver updates for 5.16-rc1.
Nothing major in here at all, just lots of tiny serial and tty driver
updates for various reported things, and some good cleanups. These
include:
- more good tty api cleanups from Jiri
- stm32 serial driver updates
- softlockup fix for non-preempt systems under high serial load
- rpmsg serial driver update
- 8250 drivers updates and fixes
- n_gsm line discipline fixes and updates as people are finally
starting to use it.
All of these have been in linux-next for a while now with no reported
issues"
* tag 'tty-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (86 commits)
tty: Fix extra "not" in TTY_DRIVER_REAL_RAW description
serial: cpm_uart: Protect udbg definitions by CONFIG_SERIAL_CPM_CONSOLE
tty: rpmsg: Define tty name via constant string literal
tty: rpmsg: Add pr_fmt() to prefix messages
tty: rpmsg: Use dev_err_probe() in ->probe()
tty: rpmsg: Unify variable used to keep an error code
tty: rpmsg: Assign returned id to a local variable
serial: stm32: push DMA RX data before suspending
serial: stm32: terminate / restart DMA transfer at suspend / resume
serial: stm32: rework RX dma initialization and release
serial: 8250_pci: Remove empty stub pci_quatech_exit()
serial: 8250_pci: Replace custom pci_match_id() implementation
serial: xilinx_uartps: Fix race condition causing stuck TX
serial: sunzilog: Mark sunzilog_putchar() __maybe_unused
Revert "tty: hvc: pass DMA capable memory to put_chars()"
Revert "virtio-console: remove unnecessary kmemdup()"
serial: 8250_pci: Replace dev_*() by pci_*() macros
serial: 8250_pci: Get rid of redundant 'else' keyword
serial: 8250_pci: Refactor the loop in pci_ite887x_init()
tty: add rpmsg driver
...
If CONFIG_CONSOLE_POLL=y, and CONFIG_SERIAL_CPM=m (hence
CONFIG_SERIAL_CPM_CONSOLE=n):
drivers/tty/serial/cpm_uart/cpm_uart_core.c:1109:12: warning: ‘udbg_cpm_getc’ defined but not used [-Wunused-function]
1109 | static int udbg_cpm_getc(void)
| ^~~~~~~~~~~~~
drivers/tty/serial/cpm_uart/cpm_uart_core.c:1095:13: warning: ‘udbg_cpm_putc’ defined but not used [-Wunused-function]
1095 | static void udbg_cpm_putc(char c)
| ^~~~~~~~~~~~~
Fix this by making the udbg definitions depend on
CONFIG_SERIAL_CPM_CONSOLE, in addition to CONFIG_CONSOLE_POLL.
Fixes: a60526097f ("tty: serial: cpm_uart: Add udbg support for enabling xmon")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20211027075326.3270785-1-geert@linux-m68k.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Data may be stored in DMA RX buffer, when suspending. The data needs
to be pushed to the upper layer. We can't rely on the timeout IRQ (RTOR)
that can't be triggered into low power state. So safely clear DMA request
(DMAR), force the DMA reception routines to push RX buffer content, before
disabling RX DMA. This way, handover to pio mode is safe.
Only call tty_flip_buffer_push() when there is RX data to handle.
Move the locking outside of stm32_usart_receive_chars() to prevent a race
condition, when disabling DMA request upon suspend / pm_runtime_suspend.
Data may be received under IRQ and pushed before
stm32_usart_receive_chars() has pushed older data from DMA rx_buf upon
suspend.
The sequence in suspend routine needs proper locking to avoid this.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-4-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
DMA prevents the system to suspend when an UART RX wake-up source is
using DMA. DMA can't suspend while DMA channels are still active.
Terminate DMA transfer at suspend, and restart a new DMA transfer at
resume. Create stm32_usart_start_rx_dma_cyclic function to factorize
dma RX initialization. Move RX DMA code related to wakeup into
stm32_usart_serial_en_wakeup() routine to ease further improvements
on wakeup from low power modes.
Don't enable/disable wakeup on uninitialized port.
There may be data residue in the RX FIFO while suspending. Flush it at
suspend time. Receiver timeout interrupt won't trigger later in low power
mode, so call stm32_usart_receive_chars() in case there's data to handle.
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-3-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The RX DMA channel is kept active forever (from the probe). That prevents
going to low power mode when it is used. This change moves the
DMA configuration and enabling procedures to startup routine to allow
transition to low power mode.
The DMA disabling procedure is implemented in stop_rx routine as this
ops has to stop characters reception, and DMA transation in shutdown.
Clean useless dma_async_tx_descriptor initialization to NULL value.
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-2-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
