5246 Commits

Author SHA1 Message Date
Claudiu Beznea
aec079f887 tty: serial: atmel: use macros instead of hardcoded values
Use UART_PM_STATE_ON, UART_PM_STATE_OFF instead of hardcoded values.

Reviewed-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20211007112014.2332019-1-claudiu.beznea@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-10 15:20:09 +02:00
Johan Hovold
d02b006b29 Revert "serial: 8250: Fix reporting real baudrate value in c_ospeed field"
This reverts commit 32262e2e429cdb31f9e957e997d53458762931b7.

The commit in question claims to determine the inverse of
serial8250_get_divisor() but failed to notice that some drivers override
the default implementation using a get_divisor() callback.

This means that the computed line-speed values can be completely wrong
and results in regular TCSETS requests failing (the incorrect values
would also be passed to any overridden set_divisor() callback).

Similarly, it also failed to honour the old (deprecated) ASYNC_SPD_FLAGS
and would break applications relying on those when re-encoding the
actual line speed.

There are also at least two quirks, UART_BUG_QUOT and an OMAP1510
workaround, which were happily ignored and that are now broken.

Finally, even if the offending commit were to be implemented correctly,
this is a new feature and not something which should be backported to
stable.

Cc: Pali Rohár <pali@kernel.org>
Fixes: 32262e2e429c ("serial: 8250: Fix reporting real baudrate value in c_ospeed field")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211007133146.28949-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-07 16:22:29 +02:00
Johan Hovold
cb2282213e serial: 8250: allow disabling of Freescale 16550 compile test
The SERIAL_8250_FSL option is used to enable a workaround for a
break-detection erratum for Freescale 16550 UARTs in the 8250 driver and
is currently also used to enable support for ACPI enumeration.

It is enabled on PPC, ARM and ARM64 whenever 8250 console support is
enabled (since the quirk is needed for sysrq handling).

Commit b1442c55ce89 ("serial: 8250: extend compile-test coverage")
enabled compile testing of the code in question but did not provide a
means to disable the option when COMPILE_TEST is enabled.

Add a conditional input prompt instead so that SERIAL_8250_FSL is no
longer enabled by default when compile testing while continuing to
always enable the quirk for platforms that may need it.

Fixes: b1442c55ce89 ("serial: 8250: extend compile-test coverage")
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20210924141232.4419-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-05 15:07:44 +02:00
Pali Rohár
32262e2e42 serial: 8250: Fix reporting real baudrate value in c_ospeed field
In most cases it is not possible to set exact baudrate value to hardware.

So fix reporting real baudrate value which was set to hardware via c_ospeed
termios field. It can be retrieved by ioctl(TCGETS2) from userspace.

Real baudrate value is calculated from chosen hardware divisor and base
clock. It is implemented in a new function serial8250_compute_baud_rate()
which is inverse of serial8250_get_divisor() function.

With this change is fixed also UART timeout value (it is updated via
uart_update_timeout() function), which is calculated from the now fixed
baudrate value too.

Cc: stable@vger.kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20210927093704.19768-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-05 15:02:58 +02:00
Pali Rohár
027b57170b serial: core: Fix initializing and restoring termios speed
Since commit edc6afc54968 ("tty: switch to ktermios and new framework")
termios speed is no longer stored only in c_cflag member but also in new
additional c_ispeed and c_ospeed members. If BOTHER flag is set in c_cflag
then termios speed is stored only in these new members.

Therefore to correctly restore termios speed it is required to store also
ispeed and ospeed members, not only cflag member.

In case only cflag member with BOTHER flag is restored then functions
tty_termios_baud_rate() and tty_termios_input_baud_rate() returns baudrate
stored in c_ospeed / c_ispeed member, which is zero as it was not restored
too. If reported baudrate is invalid (e.g. zero) then serial core functions
report fallback baudrate value 9600. So it means that in this case original
baudrate is lost and kernel changes it to value 9600.

Simple reproducer of this issue is to boot kernel with following command
line argument: "console=ttyXXX,86400" (where ttyXXX is the device name).
For speed 86400 there is no Bnnn constant and therefore kernel has to
represent this speed via BOTHER c_cflag. Which means that speed is stored
only in c_ospeed and c_ispeed members, not in c_cflag anymore.

If bootloader correctly configures serial device to speed 86400 then kernel
prints boot log to early console at speed speed 86400 without any issue.
But after kernel starts initializing real console device ttyXXX then speed
is changed to fallback value 9600 because information about speed was lost.

This patch fixes above issue by storing and restoring also ispeed and
ospeed members, which are required for BOTHER flag.

Fixes: edc6afc54968 ("[PATCH] tty: switch to ktermios and new framework")
Cc: stable@vger.kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20211002130900.9518-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-05 15:02:44 +02:00
Colin Ian King
27e8c8b483 serial: sifive: set pointer to NULL rather than 0.
Clean up the assignment of sifive_serial_console_ports[ssp->port.line],
this is a pointer to a struct sifive_serial_port so the assignment
should be a NULL rather than a integer 0.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20210925224726.183360-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-05 14:54:21 +02:00
Krzysztof Kozlowski
e01f9125e7 tty: serial: samsung: describe driver in KConfig
Describe better which driver applies to which SoC, to make configuring
kernel for Samsung SoC easier.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20210924133040.111706-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-05 14:04:13 +02:00
Greg Kroah-Hartman
5ecb11dd89 Merge 5.15-rc3 into tty-next
We need the tty fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-27 16:36:09 +02:00
Geert Uytterhoeven
2a7458ed06 serial: 8250: SERIAL_8250_EM should depend on ARCH_RENESAS
The Emma Mobile integrated serial port hardware is only present on Emma
Mobile SoCs.  Hence add a dependency on ARCH_RENESAS, to prevent asking
the user about this driver when configuring a kernel without Renesas
ARM32 SoC support.

Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/7b5a4bbf2f47b2c4c127817e8b1524a650795d97.1631710085.git.geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-22 16:59:13 +02:00
Krzysztof Kozlowski
5c7dcc4fd0 serial: 8250: remove duplicated BRI0A49 and BDP3336 entries
BRI0A49 and BDP3336 are already on the list.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20210916170859.138813-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-22 16:59:13 +02:00
Geert Uytterhoeven
28f5cb3715 serial: 8250_fsl: Move fsl8250_data to ACPI section
The fsl8250_data structure is only used by ACPI support.
Hence move its definition to the driver's ACPI section.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/e406730a5eab880448d6bb55fbce492d281034ef.1631710623.git.geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-22 16:59:13 +02:00
Pali Rohár
74e1eb3b4a serial: mvebu-uart: fix driver's tx_empty callback
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: 30530791a7a0 ("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>
2021-09-14 10:07:10 +02:00
Nishanth Menon
79e9e30a92 serial: 8250: 8250_omap: Fix RX_LVL register offset
Commit b67e830d38fa ("serial: 8250: 8250_omap: Fix possible interrupt
storm on K3 SoCs") introduced fixup including a register read to
RX_LVL, however, we should be using word offset than byte offset
since our registers are on 4 byte boundary (port.regshift = 2) for
8250_omap.

Fixes: b67e830d38fa ("serial: 8250: 8250_omap: Fix possible interrupt storm on K3 SoCs")
Cc: stable <stable@vger.kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Link: https://lore.kernel.org/r/20210903050550.29050-1-nm@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-14 10:06:37 +02:00
Sean Anderson
ea017f5853 tty: serial: uartlite: Prevent changing fixed parameters
This device does not support changing baud, parity, data bits, stop
bits, or detecting breaks. Disable "changing" these settings to prevent
their termios from diverging from the actual state of the uart.

In order to determine the correct parameters to enforce, we read the
various new devicetree parameters to discover how the uart was
configured when it was synthesized. The defaults match
ulite_console_setup. xlnx,use-parity, xlnx,odd-parity, and
xlnx,data-bits are optional since there were in-tree users (and
presumably out-of-tree users) who did not set them.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Link: https://lore.kernel.org/r/20210826192154.3202269-5-sean.anderson@seco.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-14 10:05:32 +02:00
Len Baker
42c457cc9a serial: 8250_pci: Prefer struct_size over open coded arithmetic
As noted in the "Deprecated Interfaces, Language Features, Attributes,
and Conventions" documentation [1], size calculations (especially
multiplication) should not be performed in memory allocator (or similar)
function arguments due to the risk of them overflowing. This could lead
to values wrapping around and a smaller allocation being made than the
caller was expecting. Using those allocations could lead to linear
overflows of heap memory and other misbehaviors.

So, use the struct_size() helper to do the arithmetic instead of the
argument "size + size * count" in the kzalloc() function.

[1] https://www.kernel.org/doc/html/v5.14/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Len Baker <len.baker@gmx.com>
Link: https://lore.kernel.org/r/20210905155728.11147-1-len.baker@gmx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-14 10:00:51 +02:00
Linus Torvalds
a2d616b935 parisc architecture updates for kernel 5.15:
- Fix a kernel crash when a signal is delivered to bad userspace stack
 - Fix fall-through warnings in math-emu code
 - Increase size of gcc stack frame check
 - Switch coding from 'pci_' to 'dma_' API
 - Make struct parisc_driver::remove() return void
 - Some parisc related Makefile changes
 - Minor cleanups, e.g. change to octal permissions, fix macro collisions,
   fix PMD_ORDER collision, replace spaces with tabs
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Merge tag 'for-5.15/parisc' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux

Pull parisc architecture updates from Helge Deller:

 - Fix a kernel crash when a signal is delivered to bad userspace stack

 - Fix fall-through warnings in math-emu code

 - Increase size of gcc stack frame check

 - Switch coding from 'pci_' to 'dma_' API

 - Make struct parisc_driver::remove() return void

 - Some parisc related Makefile changes

 - Minor cleanups, e.g. change to octal permissions, fix macro
   collisions, fix PMD_ORDER collision, replace spaces with tabs

* tag 'for-5.15/parisc' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: math-emu: Fix fall-through warnings
  parisc: fix crash with signals and alloca
  parisc: Fix compile failure when building 64-bit kernel natively
  parisc: ccio-dma.c: Added tab instead of spaces
  parisc/parport_gsc: switch from 'pci_' to 'dma_' API
  parisc: move core-y in arch/parisc/Makefile to arch/parisc/Kbuild
  parisc: switch from 'pci_' to 'dma_' API
  parisc: Make struct parisc_driver::remove() return void
  parisc: remove unused arch/parisc/boot/install.sh and its phony target
  parisc: Rename PMD_ORDER to PMD_TABLE_ORDER
  parisc: math-emu: Avoid "fmt" macro collision
  parisc: Increase size of gcc stack frame check
  parisc: Replace symbolic permissions with octal permissions
2021-09-02 13:16:00 -07:00
Uwe Kleine-König
87875c1084 parisc: Make struct parisc_driver::remove() return void
The caller of this function (parisc_driver_remove() in
arch/parisc/kernel/drivers.c) ignores the return value, so better don't
return any value at all to not wake wrong expectations in driver authors.

The only function that could return a non-zero value before was
ipmi_parisc_remove() which returns the return value of
ipmi_si_remove_by_dev(). Make this function return void, too, as for all
other callers the value is ignored, too.

Also fold in a small checkpatch fix for:

WARNING: Unnecessary space before function pointer arguments
+	void (*remove) (struct parisc_device *dev);

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> (for drivers/input)
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by:  Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2021-08-30 10:18:25 +02:00
Sean Anderson
2e5f3a69b6 tty: serial: uartlite: Use read_poll_timeout for a polling loop
read_poll_timeout was recently introduced, and can be used to simplify
our console polling loop. This results in a slight reduction in code.
early_uartlite_putc can't get the same treatment, because it can be
called before udelay is set up.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Link: https://lore.kernel.org/r/20210826192549.3203071-1-sean.anderson@seco.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-27 16:34:32 +02:00
Sean Anderson
3620a89b7d tty: serial: uartlite: Use constants in early_uartlite_putc
Use the constants defined at the beginning of this file instead of
integer literals when accessing registers. This makes this code easier
to read, and obviates the need for some explanatory comments.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Link: https://lore.kernel.org/r/20210826194323.3209227-1-sean.anderson@seco.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-27 16:34:04 +02:00
Tang Bin
74d2fb7e70 serial: vt8500: Use of_device_get_match_data
Retrieve OF match data, it's better and cleaner to use
'of_device_get_match_data' over 'of_match_device'.

Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20210822032806.3256-4-tangbin@cmss.chinamobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-26 14:51:10 +02:00
Tang Bin
a6a65f9ee0 serial: tegra: Use of_device_get_match_data
Retrieve OF match data, it's better and cleaner to use
'of_device_get_match_data' over 'of_match_device'.

Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20210822032806.3256-3-tangbin@cmss.chinamobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-26 14:51:10 +02:00
Tang Bin
618bf2b04b serial: 8250_ingenic: Use of_device_get_match_data
Retrieve OF match data, it's better and cleaner to use
'of_device_get_match_data' over 'of_match_device'.

Acked-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20210822032806.3256-2-tangbin@cmss.chinamobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-26 14:51:10 +02:00
Tang Bin
fa934fc1a8 tty: serial: linflexuart: Remove redundant check to simplify the code
In the function uart_add_one_port(), it can return zero or non-zero,
so remove redundant check to simplify the code.

Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20210823110754.11232-1-tangbin@cmss.chinamobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-26 14:51:04 +02:00
Fugang Duan
bd5305dcab tty: serial: fsl_lpuart: do software reset for imx7ulp and imx8qxp
Do software reset for communication port on imx7ulp and imx8qxp after
the port is registered if the UART controller support the feature.

Do partition reset with LPUART's power on, LPUART registers will
keep the previous status, like on i.MX8QXP platform, which is not
expected action, so need to set the RST bit of GLOBAL register to reset
all uart internal logic and registers.

Currently, only i.MX7ULP and i.MX8QXP LPUART controllers include
global register that support the software reset.

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20210823091801.17447-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-26 14:49:20 +02:00
Fugang Duan
48422152a8 tty: serial: fsl_lpuart: enable two stop bits for lpuart32
Add two stop bits support.
User can run the command to enable two stop bits for test:
stty  cstopb  -F /dev/ttyLPx

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20210823081733.31941-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-26 14:49:14 +02:00
Andy Duan
d5c3894844 tty: serial: fsl_lpuart: fix the wrong mapbase value
Register offset needs to be applied on mapbase also.
dma_tx/rx_request use the physical address of UARTDATA.
Register offset is currently only applied to membase (the
corresponding virtual addr) but not on mapbase.

Fixes: 24b1e5f0e83c ("tty: serial: lpuart: add imx7ulp support")
Reviewed-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Adriana Reus <adriana.reus@nxp.com>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Signed-off-by: Andy Duan <fugang.duan@nxp.com>
Link: https://lore.kernel.org/r/20210819021033.32606-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-26 14:49:03 +02:00
Fugang Duan
88c1d2478e tty: serial: fsl_lpuart: check dma_tx_in_progress in tx dma callback
There have a corner case that tx DMA .callback() is coming after
.flush_buffer(), then .callback() should check dma_tx_in_progress
flag and return in directly.

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20210817100203.21300-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-18 16:05:27 +02:00
Ulrich Hecht
87b8061bad serial: sh-sci: fix break handling for sysrq
This fixes two issues that cause the sysrq sequence to be inadvertently
aborted on SCIF serial consoles:

- a NUL character remains in the RX queue after a break has been detected,
  which is then passed on to uart_handle_sysrq_char()
- the break interrupt is handled twice on controllers with multiplexed ERI
  and BRI interrupts

Signed-off-by: Ulrich Hecht <uli+renesas@fpond.eu>
Link: https://lore.kernel.org/r/20210816162201.28801-1-uli+renesas@fpond.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-16 18:53:40 +02:00
Tang Bin
3d881e32e2 serial: stm32: use devm_platform_get_and_ioremap_resource()
Use devm_platform_get_and_ioremap_resource() to simplify code.

Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20210814131418.13608-1-tangbin@cmss.chinamobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-16 18:53:15 +02:00
Tang Bin
59bd4eedf1 serial: stm32: use the defined variable to simplify code
Use the defined variable 'dev' to make the code cleaner.

Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20210814124951.30084-1-tangbin@cmss.chinamobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-16 18:52:59 +02:00
Qian Cai
94560f6156 Revert "arm pl011 serial: support multi-irq request"
This reverts commit b0819465be8be0c76af15436a9e6db4dab4c196e which
results in amba_device-specific code being called from
sbsa_uart_startup() and sbsa_uart_shutdown().

Signed-off-by: Qian Cai <quic_qiancai@quicinc.com>
Link: https://lore.kernel.org/r/20210813163135.205-1-quic_qiancai@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-16 18:52:08 +02:00
Sam Protsenko
9a4d22f795 tty: serial: samsung: Add Exynos850 SoC data
Add serial driver data for Exynos850 SoC. This driver data is basically
reusing EXYNOS_COMMON_SERIAL_DRV_DATA, which is common for all Exynos
chips, but also enables USI init, which was added in previous commit:
"tty: serial: samsung: Init USI to keep clocks running".

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Link: https://lore.kernel.org/r/20210811114827.27322-7-semen.protsenko@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-13 09:15:25 +02:00
Sam Protsenko
f63299b397 tty: serial: samsung: Fix driver data macros style
Make checkpatch happy by fixing this error:

    ERROR: Macros with complex values should be enclosed in parentheses

Although this change is made to keep macros consistent with consequent
patches (adding driver data for new SoC), it's intentionally added as a
separate patch to ease possible porting efforts in future.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Link: https://lore.kernel.org/r/20210811114827.27322-6-semen.protsenko@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-13 09:15:01 +02:00
Sam Protsenko
920792aa44 tty: serial: samsung: Init USI to keep clocks running
UART block is a part of USI (Universal Serial Interface) IP-core in
Samsung SoCs since Exynos9810 (e.g. in Exynos850). USI allows one to
enable one of three types of serial interface: UART, SPI or I2C. That's
possible because USI shares almost all internal circuits within each
protocol. USI also provides some additional registers so it's possible
to configure it.

One USI register called USI_OPTION has reset value of 0x0. Because of
this the clock gating behavior is controlled by hardware (HWACG =
Hardware Auto Clock Gating), which simply means the serial won't work
after reset as is. In order to make it work, USI_OPTION[2:1] bits must
be set to 0b01, so that HWACG is controlled manually (by software).
Bits meaning:
  - CLKREQ_ON = 1: clock is continuously provided to IP
  - CLKSTOP_ON = 0: drive IP_CLKREQ to High (needs to be set along with
                    CLKREQ_ON = 1)

USI is not present on older chips, like s3c2410, s3c2412, s3c2440,
s3c6400, s5pv210, exynos5433, exynos4210. So the new boolean field
'.has_usi' was added to struct s3c24xx_uart_info. USI registers will be
only actually accessed when '.has_usi' field is set to "1".

This feature is needed for further serial enablement on Exynos850, but
some other new Exynos chips (like Exynos9810) may benefit from this
feature as well.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Link: https://lore.kernel.org/r/20210811114827.27322-5-semen.protsenko@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-13 09:14:36 +02:00
Tang Bin
217b04c67b serial: stm32: fix the conditional expression writing
In the function stm32_usart_init_port, intent of the code maybe when
irq returns a value of zero, the return should be '-ENODEV'. But the
conditional expression '? :' maybe clerical error, it should be
'?:' to make '-ENODEV' work.
But in fact, as the example in platform.c is
  * int irq = platform_get_irq(pdev, 0);
  * if (irq < 0)
  * return irq;
So the return value of zero is unnecessary to check, at last remove
the unnecessary '?: -ENODEV'.

Co-developed-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20210811105136.25392-1-tangbin@cmss.chinamobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-13 09:11:21 +02:00
Greg Kroah-Hartman
15e580283f Merge 5.14-rc5 into tty-next
We need the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-09 08:52:46 +02:00
Tony Lindgren
1fe0e1fa32 serial: 8250_omap: Handle optional overrun-throttle-ms property
Handle optional overrun-throttle-ms property as done for 8250_fsl in commit
6d7f677a2afa ("serial: 8250: Rate limit serial port rx interrupts during
input overruns"). This can be used to rate limit the UART interrupts on
noisy lines that end up producing messages like the following:

ttyS ttyS2: 4 input overrun(s)

At least on droid4, the multiplexed USB and UART port is left to UART mode
by the bootloader for a debug console, and if a USB charger is connected
on boot, we get noise on the UART until the PMIC related drivers for PHY
and charger are loaded.

With this patch and overrun-throttle-ms = <500> we avoid the extra rx
interrupts.

Cc: Carl Philipp Klemm <philipp@uvos.xyz>
Cc: Merlijn Wajer <merlijn@wizzup.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20210727103533.51547-2-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-05 14:01:25 +02:00
Mario Kleiner
341abd693d serial: 8250_pci: Avoid irq sharing for MSI(-X) interrupts.
This attempts to fix a bug found with a serial port card which uses
an MCS9922 chip, one of the 4 models for which MSI-X interrupts are
currently supported. I don't possess such a card, and i'm not
experienced with the serial subsystem, so this patch is based on what
i think i found as a likely reason for failure, based on walking the
user who actually owns the card through some diagnostic.

The user who reported the problem finds the following in his dmesg
output for the relevant ttyS4 and ttyS5:

[    0.580425] serial 0000:02:00.0: enabling device (0000 -> 0003)
[    0.601448] 0000:02:00.0: ttyS4 at I/O 0x3010 (irq = 125, base_baud = 115200) is a ST16650V2
[    0.603089] serial 0000:02:00.1: enabling device (0000 -> 0003)
[    0.624119] 0000:02:00.1: ttyS5 at I/O 0x3000 (irq = 126, base_baud = 115200) is a ST16650V2
...
[    6.323784] genirq: Flags mismatch irq 128. 00000080 (ttyS5) vs. 00000000 (xhci_hcd)
[    6.324128] genirq: Flags mismatch irq 128. 00000080 (ttyS5) vs. 00000000 (xhci_hcd)
...

Output of setserial -a:

/dev/ttyS4, Line 4, UART: 16650V2, Port: 0x3010, IRQ: 127
	Baud_base: 115200, close_delay: 50, divisor: 0
	closing_wait: 3000
	Flags: spd_normal skip_test

This suggests to me that the serial driver wants to register and share a
MSI/MSI-X irq 128 with the xhci_hcd driver, whereas the xhci driver does
not want to share the irq, as flags 0x00000080 (== IRQF_SHARED) from the
serial port driver means to share the irq, and this mismatch ends in some
failed irq init?

With this setup, data reception works very unreliable, with dropped data,
already at a transmission rate of only a 16 Bytes chunk every 1/120th of
a second, ie. 1920 Bytes/sec, presumably due to rx fifo overflow due to
mishandled or not used at all rx irq's?

See full discussion thread with attempted diagnosis at:

https://psychtoolbox.discourse.group/t/issues-with-iscan-serial-port-recording/3886

Disabling the use of MSI interrupts for the serial port pci card did
fix the reliability problems. The user executed the following sequence
of commands to achieve this:

echo 0000:02:00.0 | sudo tee /sys/bus/pci/drivers/serial/unbind
echo 0000:02:00.1 | sudo tee /sys/bus/pci/drivers/serial/unbind

echo 0 | sudo tee /sys/bus/pci/devices/0000:02:00.0/msi_bus
echo 0 | sudo tee /sys/bus/pci/devices/0000:02:00.1/msi_bus

echo 0000:02:00.0 | sudo tee /sys/bus/pci/drivers/serial/bind
echo 0000:02:00.1 | sudo tee /sys/bus/pci/drivers/serial/bind

This resulted in the following log output:

[   82.179021] pci 0000:02:00.0: MSI/MSI-X disallowed for future drivers
[   87.003031] pci 0000:02:00.1: MSI/MSI-X disallowed for future drivers
[   98.537010] 0000:02:00.0: ttyS4 at I/O 0x3010 (irq = 17, base_baud = 115200) is a ST16650V2
[  103.648124] 0000:02:00.1: ttyS5 at I/O 0x3000 (irq = 18, base_baud = 115200) is a ST16650V2

This patch attempts to fix the problem by disabling irq sharing when
using MSI irq's. Note that all i know for sure is that disabling MSI
irq's fixed the problem for the user, so this patch could be wrong and
is untested. Please review with caution, keeping this in mind.

Fixes: 8428413b1d14 ("serial: 8250_pci: Implement MSI(-X) support")
Cc: Ralf Ramsauer <ralf.ramsauer@oth-regensburg.de>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Link: https://lore.kernel.org/r/20210729043306.18528-1-mario.kleiner.de@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-30 13:06:19 +02:00
Zhiyong Tao
7c4a509d38 serial: 8250_mtk: fix uart corruption issue when rx power off
Fix uart corruption issue when rx power off.
Add spin lock in mtk8250_dma_rx_complete function in APDMA mode.

when uart is used as a communication port with external device(GPS).
when external device(GPS) power off, the power of rx pin is also from
1.8v to 0v. Even if there is not any data in rx. But uart rx pin can
capture the data "0".
If uart don't receive any data in specified cycle, uart will generates
BI(Break interrupt) interrupt.
If external device(GPS) power off, we found that BI interrupt appeared
continuously and very frequently.
When uart interrupt type is BI, uart IRQ handler(8250 framwork
API:serial8250_handle_irq) will push data to tty buffer.
mtk8250_dma_rx_complete is a task of mtk_uart_apdma_rx_handler.
mtk8250_dma_rx_complete priority is lower than uart irq
handler(serial8250_handle_irq).
if we are in process of mtk8250_dma_rx_complete, uart appear BI
interrupt:1)serial8250_handle_irq will priority execution.2)it may cause
write tty buffer conflict in mtk8250_dma_rx_complete.
So the spin lock protect the rx receive data process is not break.

Signed-off-by: Zhiyong Tao <zhiyong.tao@mediatek.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210729084640.17613-2-zhiyong.tao@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-29 17:06:37 +02:00
Sherry Sun
06e91df16f tty: serial: fsl_lpuart: fix the wrong return value in lpuart32_get_mctrl
Patch e60c2991f18b make the lpuart32_get_mctrl always return 0, actually
this will break the functions of device which use flow control such as
Bluetooth.
For lpuart32 plaform, the hardware can handle the CTS automatically.
So we should set TIOCM_CTS active. Also need to set CAR and DSR active.

Patch has been tested on lpuart32 platforms such as imx8qm and imx8ulp.

Fixes: e60c2991f18b ("serial: fsl_lpuart: remove RTSCTS handling from get_mctrl()")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20210729083109.31541-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-29 17:05:59 +02:00
Tony Lindgren
6c44eb5905 serial: omap: Only allow if 8250_omap is not selected
For years we've been carrying legacy omap-serial in addition to
8250_omap driver and 8250_omap should be used instead.

Let's finally start planning on removing omap-serial by first not
building it if 8250_omap is selected to save some memory.

The defconfigs have switched over to using 8250_omap, and we have
a fixup in place for the the serial console since commit 00648d0282dc
("tty: serial: 8250: omap: add ttySx console if the user didn't").
So people updating their systems without omap-serial will see
boot time warnings on what is going on.

Cc: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Dario Binacchi <dariobin@libero.it>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20210727103149.51175-2-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-29 17:03:04 +02:00
Tony Lindgren
33e5571ebd serial: omap: Disable PM runtime autoidle to remove pm_runtime_irq_safe()
We want to remove the use of pm_runtime_irq_safe() from serial drivers
to allow making PM runtime handling generic. Let's simplify things by
disabling PM runtime autoidle for omap-serial as this driver has been
deprecated for years because of the 8250_omap driver.

There are still some omap-serial users that seem to hang on to it for
some unknown rs485 reasons it seems. But presumably those folks do not
need PM runtime autoidle with omap-serial, and hopefully can just move
to using 8250_omap driver instead.

For 8250_omap driver, we will eventually move to use generic serial
layer PM based on patches done by Andy Shevchenko to remove
pm_runtime_irq_safe() usage.

Cc: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Dario Binacchi <dariobin@libero.it>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20210727103149.51175-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-29 17:03:04 +02:00
Greg Kroah-Hartman
3a96e97ab4 serial: 8250_pci: make setup_port() parameters explicitly unsigned
The bar and offset parameters to setup_port() are used in pointer math,
and while it would be very difficult to get them to wrap as a negative
number, just be "safe" and make them unsigned so that static checkers do
not trip over them unintentionally.

Cc: Jiri Slaby <jirislaby@kernel.org>
Reported-by: Jordy Zomer <jordy@pwning.systems>
Link: https://lore.kernel.org/r/20210726130717.2052096-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-27 12:21:21 +02:00
Jiri Slaby
9f90a4ddef tty: drop put_tty_driver
put_tty_driver() is an alias for tty_driver_kref_put(). There is no need
for two exported identical functions, therefore switch all users of
old put_tty_driver() to new tty_driver_kref_put() and remove the former
for good.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Cc: Jens Taprogge <jens.taprogge@taprogge.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Scott Branden <scott.branden@broadcom.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Lin <dtwlin@gmail.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: David Sterba <dsterba@suse.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Oliver Neukum <oneukum@suse.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Mathias Nyman <mathias.nyman@intel.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Acked-by: Alex Elder <elder@linaro.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: David Sterba <dsterba@suse.com>
Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210723074317.32690-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-27 12:17:21 +02:00
Jiri Slaby
39b7b42be4 tty: stop using alloc_tty_driver
alloc_tty_driver was deprecated by tty_alloc_driver in commit
7f0bc6a68ed9 (TTY: pass flags to alloc_tty_driver) in 2012.

I never got into eliminating alloc_tty_driver until now. So we still
have two functions for allocating drivers which might be confusing. So
get rid of alloc_tty_driver uses to eliminate it for good in the next
patch.

Note we need to switch return value checking as tty_alloc_driver uses
ERR_PTR. And flags are now a parameter of tty_alloc_driver.

Cc: Richard Henderson <rth@twiddle.net>(odd fixer:ALPHA PORT)
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Cc: Jens Taprogge <jens.taprogge@taprogge.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: David Sterba <dsterba@suse.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Oliver Neukum <oneukum@suse.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Johan Hovold <johan@kernel.org>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: David Sterba <dsterba@suse.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210723074317.32690-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-27 12:17:20 +02:00
Andy Shevchenko
3d1fa055ea serial: max310x: Use clock-names property matching to recognize EXTCLK
Dennis reported that on ACPI-based systems the clock frequency
isn't enough to configure device properly. We have to respect
the clock source as well. To achieve this match the clock-names
property against "osc" to recognize external clock connection.
On DT-based system this doesn't change anything.

Reported-and-tested-by: Dennis Giaya <dgiaya@whoi.edu>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210723125943.22039-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-27 12:09:18 +02:00
Andy Shevchenko
0a9410b981 serial: 8250_lpss: Enable DMA on Intel Elkhart Lake
PSE UARTs on Intel Elkhart Lake support DMA mode.
Enable DMA on these ports.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210721162452.48764-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-27 12:08:20 +02:00
Maciej W. Rozycki
d7aff291d0 serial: 8250: Define RX trigger levels for OxSemi 950 devices
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>
2021-07-27 12:05:46 +02:00
Andy Shevchenko
7f0909db76 serial: 8250_pci: Enumerate Elkhart Lake UARTs via dedicated driver
Elkhart Lake UARTs are PCI enumerated Synopsys DesignWare v4.0+ UART
integrated with Intel iDMA 32-bit DMA controller. There is a specific
driver to handle them, i.e. 8250_lpss. Hence, disable 8250_pci
enumeration for these UARTs.

Fixes: 1b91d97c66ef ("serial: 8250_lpss: Add ->setup() for Elkhart Lake ports")
Fixes: 4f912b898dc2 ("serial: 8250_lpss: Enable HS UART on Elkhart Lake")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210713101739.36962-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-21 12:54:11 +02:00
Johan Hovold
853a9ae29e serial: 8250: fix handle_irq locking
The 8250 handle_irq callback is not just called from the interrupt
handler but also from a timer callback when polling (e.g. for ports
without an interrupt line). Consequently the callback must explicitly
disable interrupts to avoid a potential deadlock with another interrupt
in polled mode.

Add back an irqrestore-version of the sysrq port-unlock helper and use
it in the 8250 callbacks that need it.

Fixes: 75f4e830fa9c ("serial: do not restore interrupt state in sysrq helper")
Cc: stable@vger.kernel.org	# 5.13
Cc: Joel Stanley <joel@jms.id.au>
Cc: Andrew Jeffery <andrew@aj.id.au>
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210714080427.28164-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-21 12:53:26 +02:00