RS485-enabled UART ports on TI Sitara SoCs with active-low polarity
exhibit a Transmit Enable glitch on ->set_termios():
omap8250_restore_regs(), which is called from omap_8250_set_termios(),
sets the TCRTLR bit in the MCR register and clears all other bits,
including RTS. If RTS uses active-low polarity, it is now asserted
for no reason.
The TCRTLR bit is subsequently cleared by writing up->mcr to the MCR
register. That variable is always zero, so the RTS bit is still cleared
(incorrectly so if RTS is active-high).
(up->mcr is not, as one might think, a cache of the MCR register's
current value. Rather, it only caches a single bit of that register,
the AFE bit. And it only does so if the UART supports the AFE bit,
which OMAP does not. For details see serial8250_do_set_termios() and
serial8250_do_set_mctrl().)
Finally at the end of omap8250_restore_regs(), the MCR register is
restored (and RTS deasserted) by a call to up->port.ops->set_mctrl()
(which equals serial8250_set_mctrl()) and serial8250_em485_stop_tx().
So there's an RTS glitch between setting TCRTLR and calling
serial8250_em485_stop_tx(). Avoid by using a read-modify-write
when setting TCRTLR.
While at it, drop a redundant initialization of up->mcr. As explained
above, the variable isn't used by the driver and it is already
initialized to zero because it is part of the static struct
serial8250_ports[] declared in 8250_core.c. (Static structs are
initialized to zero per section 6.7.8 nr. 10 of the C99 standard.)
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Su Bao Cheng <baocheng.su@siemens.com>
Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/6554b0241a2c7fd50f32576fdbafed96709e11e8.1664278942.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Convert the PDC console to an early console
* Unbreak mmap() of graphics card memory due to PAGE_SPECIAL pgtable flag
* Reduce the size of the alternative tables
* Align stifb graphics card memory size to 4MB
* Spelling fixes
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Merge tag 'parisc-for-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc updates from Helge Deller:
"Fixes:
- When we added basic vDSO support in kernel 5.18 we introduced a bug
which prevented a mmap() of graphic card memory. This is because we
used the DMB (data memory break trap bit) page flag as special-bit,
but missed to clear that bit when loading the TLB.
- Graphics card memory size was not correctly aligned
- Spelling fixes (from Colin Ian King)
Enhancements:
- PDC console (which uses firmware calls) now rewritten as early
console
- Reduced size of alternative tables"
* tag 'parisc-for-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix spelling mistake "mis-match" -> "mismatch" in eisa driver
parisc: Fix userspace graphics card breakage due to pgtable special bit
parisc: fbdev/stifb: Align graphics memory size to 4MB
parisc: Convert PDC console to an early console
parisc: Reduce kernel size by packing alternative tables
Rewrite the PDC console to become an early console.
Beside the fact that now boot information is visible until another
(text- or graphics) console takes over, this benefits as well machines
with a yet-unsupported STI console and kgdb.
Signed-off-by: Helge Deller <deller@gmx.de>
Here is the big set of TTY and Serial driver updates for 6.1-rc1.
Lots of cleanups in here, no real new functionality this time around,
with the diffstat being that we removed more lines than we added!
Included in here are:
- termios unification cleanups from Al Viro, it's nice to
finally get this work done
- tty serial transmit cleanups in various drivers in preparation
for more cleanup and unification in future releases (that work
was not ready for this release.)
- n_gsm fixes and updates
- ktermios cleanups and code reductions
- dt bindings json conversions and updates for new devices
- some serial driver updates for new devices
- lots of other tiny cleanups and janitorial stuff. Full
details in the shortlog.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here is the big set of TTY and Serial driver updates for 6.1-rc1.
Lots of cleanups in here, no real new functionality this time around,
with the diffstat being that we removed more lines than we added!
Included in here are:
- termios unification cleanups from Al Viro, it's nice to finally get
this work done
- tty serial transmit cleanups in various drivers in preparation for
more cleanup and unification in future releases (that work was not
ready for this release)
- n_gsm fixes and updates
- ktermios cleanups and code reductions
- dt bindings json conversions and updates for new devices
- some serial driver updates for new devices
- lots of other tiny cleanups and janitorial stuff. Full details in
the shortlog.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (102 commits)
serial: cpm_uart: Don't request IRQ too early for console port
tty: serial: do unlock on a common path in altera_jtaguart_console_putc()
tty: serial: unify TX space reads under altera_jtaguart_tx_space()
tty: serial: use FIELD_GET() in lqasc_tx_ready()
tty: serial: extend lqasc_tx_ready() to lqasc_console_putchar()
tty: serial: allow pxa.c to be COMPILE_TESTed
serial: stm32: Fix unused-variable warning
tty: serial: atmel: Add COMMON_CLK dependency to SERIAL_ATMEL
serial: 8250: Fix restoring termios speed after suspend
serial: Deassert Transmit Enable on probe in driver-specific way
serial: 8250_dma: Convert to use uart_xmit_advance()
serial: 8250_omap: Convert to use uart_xmit_advance()
MAINTAINERS: Solve warning regarding inexistent atmel-usart binding
serial: stm32: Deassert Transmit Enable on ->rs485_config()
serial: ar933x: Deassert Transmit Enable on ->rs485_config()
tty: serial: atmel: Use FIELD_PREP/FIELD_GET
tty: serial: atmel: Make the driver aware of the existence of GCLK
tty: serial: atmel: Only divide Clock Divisor if the IP is USART
tty: serial: atmel: Separate mode clearing between UART and USART
dt-bindings: serial: atmel,at91-usart: Add gclk as a possible USART clock
...
The main changes this time are for the organization of the Kconfig
files, introducing per-vendor top-level options on arm64 to match
those on arm32, and making the platform selection on arm32 more
uniform, in particular for the remaining StrongARM platforms that
still have a couple of special cases compared to the more recent
ones.
I also did a cleanup of the old Footbridge platform, which was
the last holdout for the phys_to_dma()/dma_to_phys() interface
that is now completely gone from arm32, completing work started
by Christoph Hellwig.
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Merge tag 'arm-soc-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC updates from Arnd Bergmann:
"The main changes this time are for the organization of the Kconfig
files, introducing per-vendor top-level options on arm64 to match
those on arm32, and making the platform selection on arm32 more
uniform, in particular for the remaining StrongARM platforms that
still have a couple of special cases compared to the more recent ones.
I also did a cleanup of the old Footbridge platform, which was the
last holdout for the phys_to_dma()/dma_to_phys() interface that is now
completely gone from arm32, completing work started by Christoph
Hellwig"
* tag 'arm-soc-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (21 commits)
ARM: aspeed: Kconfig: Fix indentation
ARM: Drop CMDLINE_* dependency on ATAGS
ARM: Drop CMDLINE_FORCE dependency on !ARCH_MULTIPLATFORM
ARM: s3c: remove orphan declarations from arch/arm/mach-s3c/devs.h
pxa: Drop if with an always false condition
ARM: orion: fix include path
ARM: shmobile: Drop selecting SOC_BUS
arm64: renesas: Drop selecting SOC_BUS
ARM: disallow PCI with MMU=n again
ARM: footbridge: remove custom DMA address handling
MAINTAINERS: Add BCM4908 maintainer to BCMBCA entry
ARM: footbridge: move isa-dma support into footbridge
ARM: footbridge: remove leftover from personal-server
ARM: footbridge: remove addin mode
arm64: Kconfig.platforms: Group NXP platforms together
arm64: Kconfig.platforms: Re-organized Broadcom menu
ARM: make ARCH_MULTIPLATFORM user-visible
ARM: fix XIP_KERNEL dependencies
ARM: Kconfig: clean up platform selection
ARM: simplify machdirs/platdirs handling
...
The drivers branch for 6.1 is a bit larger than for most releases. Most
of the changes come from SoC maintainers for the drivers/soc subsystem:
- A new driver for error handling on the NVIDIA Tegra
'control backbone' bus.
- A new driver for Qualcomm LLCC/DDR bandwidth measurement
- New Rockchip rv1126 and rk3588 power domain drivers
- DT binding updates for memory controllers, older Rockchip
SoCs, various Mediatek devices, Qualcomm SCM firmware
- Minor updates to Hisilicon LPC bus, the Allwinner SRAM
driver, the Apple rtkit firmware driver, Tegra firmware
- Minor updates for SoC drivers (Samsung, Mediatek, Renesas,
Tegra, Qualcomm, Broadcom, NXP, ...)
There are also some separate subsystem with downstream maintainers that
merge updates this way:
- Various updates and new drivers in the memory controller
subsystem for Mediatek and Broadcom SoCs
- Small set of changes in preparation to add support for FF-A
v1.1 specification later, in the Arm FF-A firmware subsystem
- debugfs support in the PSCI firmware subsystem
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Merge tag 'arm-drivers-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM driver updates from Arnd Bergmann:
"The drivers branch for 6.1 is a bit larger than for most releases.
Most of the changes come from SoC maintainers for the drivers/soc
subsystem:
- A new driver for error handling on the NVIDIA Tegra 'control
backbone' bus.
- A new driver for Qualcomm LLCC/DDR bandwidth measurement
- New Rockchip rv1126 and rk3588 power domain drivers
- DT binding updates for memory controllers, older Rockchip SoCs,
various Mediatek devices, Qualcomm SCM firmware
- Minor updates to Hisilicon LPC bus, the Allwinner SRAM driver, the
Apple rtkit firmware driver, Tegra firmware
- Minor updates for SoC drivers (Samsung, Mediatek, Renesas, Tegra,
Qualcomm, Broadcom, NXP, ...)
There are also some separate subsystem with downstream maintainers
that merge updates this way:
- Various updates and new drivers in the memory controller subsystem
for Mediatek and Broadcom SoCs
- Small set of changes in preparation to add support for FF-A v1.1
specification later, in the Arm FF-A firmware subsystem
- debugfs support in the PSCI firmware subsystem"
* tag 'arm-drivers-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (149 commits)
ARM: remove check for CONFIG_DEBUG_LL_SER3
firmware/psci: Add debugfs support to ease debugging
firmware/psci: Print a warning if PSCI doesn't accept PC mode
dt-bindings: memory: snps,dw-umctl2-ddrc: Extend schema with IRQs/resets/clocks props
dt-bindings: memory: snps,dw-umctl2-ddrc: Replace opencoded numbers with macros
dt-bindings: memory: snps,dw-umctl2-ddrc: Use more descriptive device name
dt-bindings: memory: synopsys,ddrc-ecc: Detach Zynq DDRC controller support
soc: sunxi: sram: Add support for the D1 system control
soc: sunxi: sram: Export the LDO control register
soc: sunxi: sram: Save a pointer to the OF match data
soc: sunxi: sram: Return void from the release function
soc: apple: rtkit: Add apple_rtkit_poll
soc: imx: add i.MX93 media blk ctrl driver
soc: imx: add i.MX93 SRC power domain driver
soc: imx: imx8m-blk-ctrl: Use genpd_xlate_onecell
soc: imx: imx8mp-blk-ctrl: handle PCIe PHY resets
soc: imx: imx8m-blk-ctrl: add i.MX8MP VPU blk ctrl
soc: imx: add i.MX8MP HDMI blk ctrl HDCP/HRV_MWR
soc: imx: add icc paths for i.MX8MP hsio/hdmi blk ctrl
soc: imx: add icc paths for i.MX8MP media blk ctrl
...
The following message is seen during boot and the activation of
console port gets delayed until normal serial ports activation.
[ 0.001346] irq: no irq domain found for pic@930 !
The console port doesn't need irq, perform irq reservation later,
during cpm_uart probe.
While at it, don't use NO_IRQ but 0 which is the value returned
by irq_of_parse_and_map() in case of error. By chance powerpc's
NO_IRQ has value 0 but on some architectures it is -1.
Fixes: 14d893fc68 ("powerpc/8xx: Convert CPM1 interrupt controller to platform_device")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/8bed0f30c2e9ef16ae64fb1243a16d54a48eb8da.1664526717.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
port->lock is unlocked in each branch in altera_jtaguart_console_putc(),
so do it before the "if". "status" needs not be under the lock, as the
register was already read.
Cc: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Link: https://lore.kernel.org/r/20220927111819.18516-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
TX space reads from the control register are performed in various forms
on 4 places in altera_jtaguart. Unify all those and do the read and
masking on a single place.
The new helper altera_jtaguart_tx_space() uses FIELD_GET(), so we can
drop ALTERA_JTAGUART_CONTROL_WSPACE_OFF now.
Cc: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Link: https://lore.kernel.org/r/20220927111819.18516-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
FIELD_GET() can do the job smarter and more readable. We don't even need
ASCFSTAT_TXFREEOFF. So switch to the former and remove the latter.
Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220927111819.18516-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is one more place where lqasc_tx_ready() can be used now:
lqasc_console_putchar(). So replace the open-coded variant by the
helper.
Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220927111819.18516-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no issue compiling pxa.c even in the SERIAL_8250=y case. So to
cover it in the usual configurations, add "|| COMPILE_TEST" there.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220927110528.12815-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If CONFIG_SERIAL_EARLYCON and CONFIG_OF are both not set,
gcc warns about unused variable:
drivers/tty/serial/stm32-usart.c:83:32: error: ‘stm32h7_info’ defined but not used [-Werror=unused-variable]
static struct stm32_usart_info stm32h7_info = {
^~~~~~~~~~~~
drivers/tty/serial/stm32-usart.c:61:32: error: ‘stm32f7_info’ defined but not used [-Werror=unused-variable]
static struct stm32_usart_info stm32f7_info = {
^~~~~~~~~~~~
drivers/tty/serial/stm32-usart.c:40:32: error: ‘stm32f4_info’ defined but not used [-Werror=unused-variable]
static struct stm32_usart_info stm32f4_info = {
^~~~~~~~~~~~
cc1: all warnings being treated as errors
Mark these variables as __maybe_unused to fix this.
Fixes: c7039ce904 ("serial: stm32: make info structs static to avoid sparse warnings")
Signed-off-by: Ren Zhijie <renzhijie2@huawei.com>
Link: https://lore.kernel.org/r/20220926025826.44145-1-renzhijie2@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the driver makes use of `__clk_is_enabled()` in order to
know whether a `clk_disable_unprepare()` is needed or not on the
GCLK, a new dependency has been introduced: COMMON_CLK. If this
`CONFIG_COMMON_CLK` is not enabled, whatever config may have this
driver enabled without COMMON_CLK then an undefined reference to
`__clk_is_enabled()` will be issued by the linker.
Thus, make sure that, unless `CONFIG_COMMON_CLK` is enabled, this
driver is not compiled.
Fixes: 5e3ce1f261 ("tty: serial: atmel: Make the driver aware of the existence of GCLK")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20220926143244.485578-1-sergiu.moga@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit edc6afc549 ("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.
Since commit 027b57170b ("serial: core: Fix initializing and restoring
termios speed") termios speed is available also in struct console.
So properly restore also c_ispeed and c_ospeed members after suspend to fix
restoring termios speed which is not represented by Bnnn constant.
Fixes: 4516d50aab ("serial: 8250: Use canary to restart console after suspend")
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20220924104324.4035-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a UART port is newly registered, uart_configure_port() seeks to
deassert RS485 Transmit Enable by setting the RTS bit in port->mctrl.
However a number of UART drivers interpret a set RTS bit as *assertion*
instead of deassertion: Affected drivers include those using
serial8250_em485_config() (except 8250_bcm2835aux.c) and some using
mctrl_gpio (e.g. imx.c).
Since the interpretation of the RTS bit is driver-specific, it is not
suitable as a means to centrally deassert Transmit Enable in the serial
core. Instead, the serial core must call on drivers to deassert it in
their driver-specific way. One way to achieve that is to call
->rs485_config(). It implicitly deasserts Transmit Enable.
So amend uart_configure_port() and uart_resume_port() to invoke
uart_rs485_config(). That allows removing calls to uart_rs485_config()
from drivers' ->probe() hooks and declaring the function static.
Skip any invocation of ->set_mctrl() if RS485 is enabled. RS485 has no
hardware flow control, so the modem control lines are irrelevant and
need not be touched. When leaving RS485 mode, reset the modem control
lines to the state stored in port->mctrl. That way, UARTs which are
muxed between RS485 and RS232 transceivers drive the lines correctly
when switched to RS232. (serial8250_do_startup() historically raises
the OUT1 modem signal because otherwise interrupts are not signaled on
ancient PC UARTs, but I believe that no longer applies to modern,
RS485-capable UARTs and is thus safe to be skipped.)
imx.c modifies port->mctrl whenever Transmit Enable is asserted and
deasserted. Stop it from doing that so port->mctrl reflects the RS232
line state.
8250_omap.c deasserts Transmit Enable on ->runtime_resume() by calling
->set_mctrl(). Because that is now a no-op in RS485 mode, amend the
function to call serial8250_em485_stop_tx().
fsl_lpuart.c retrieves and applies the RS485 device tree properties
after registering the UART port. Because applying now happens on
registration in uart_configure_port(), move retrieval of the properties
ahead of uart_add_one_port().
Link: https://lore.kernel.org/all/20220329085050.311408-1-matthias.schiffer@ew.tq-group.com/
Link: https://lore.kernel.org/all/8f538a8903795f22f9acc94a9a31b03c9c4ccacb.camel@ginzinger.com/
Fixes: d3b3404df3 ("serial: Fix incorrect rs485 polarity on uart open")
Cc: stable@vger.kernel.org # v4.14+
Reported-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reported-by: Roosen Henri <Henri.Roosen@ginzinger.com>
Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/2de36eba3fbe11278d5002e4e501afe0ceaca039.1663863805.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_xmit_advance() provides a common way on how to advance
the Tx queue. Use it for the sake of unification and robustness.
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220909091102.58941-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_xmit_advance() provides a common way on how to advance
the Tx queue. Use it for the sake of unification and robustness.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220909091258.68886-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The STM32 USART can control RS-485 Transmit Enable in hardware. Since
commit 7df5081cbf ("serial: stm32: Add RS485 RTS GPIO control"),
it can alternatively be controlled in software. That was done to allow
RS-485 even if the RTS pin is unavailable because it's pinmuxed to a
different function.
However the commit neglected to deassert Transmit Enable upon invocation
of the ->rs485_config() callback. Fix it.
Avoid forward declarations by moving stm32_usart_tx_empty(),
stm32_usart_rs485_rts_enable() and stm32_usart_rs485_rts_disable()
further up in the driver.
Fixes: 7df5081cbf ("serial: stm32: Add RS485 RTS GPIO control")
Cc: stable@vger.kernel.org # v5.9+
Cc: Marek Vasut <marex@denx.de>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/6059eab35dba394468335ef640df8b0050fd9dbd.1662886616.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the PWM driver was changed to disable clocks if no PWMs are enabled,
it ended up also disabling the shared parent with the UART, since the
UART doesn't do any clock enablement on its own.
To avoid these surprises, switch to clk_get_enabled().
Fixes: ace41d7564 ("pwm: sifive: Ensure the clk is enabled exactly once per running PWM")
Cc: stable <stable@kernel.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Link: https://lore.kernel.org/r/20220920160017.7315-1-olof@lixom.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8250_omap uses em485, fill in rs485_supported accordingly. This makes
RS485 work with 8250_omap again, which was broken with the introduction
of the RS485 config sanitization.
Fixes: be2e2cb1d2 ("serial: Sanitize rs485_struct")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Link: https://lore.kernel.org/r/20220916110955.161099-1-matthias.schiffer@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit bd5305dcab ("tty: serial: fsl_lpuart: do software reset
for imx7ulp and imx8qxp"), certain i.MX UARTs are reset after they've
already been registered. Register state may thus be clobbered after
user space has begun to open and access the UART.
Avoid by performing the reset prior to registration.
Fixes: bd5305dcab ("tty: serial: fsl_lpuart: do software reset for imx7ulp and imx8qxp")
Cc: stable@vger.kernel.org # v5.15+
Cc: Fugang Duan <fugang.duan@nxp.com>
Cc: Sherry Sun <sherry.sun@nxp.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/72fb646c1b0b11c989850c55f52f9ff343d1b2fa.1662884345.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert all open-coded instances of bitfields retrieval/setting
to FIELD_PREP/FIELD_GET where possible.
Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220922113347.144383-10-sergiu.moga@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previously, the atmel serial driver did not take into account the
possibility of using the more customizable generic clock as its
baudrate generator. Unless there is a Fractional Part available to
increase accuracy, there is a high chance that we may be able to
generate a baudrate closer to the desired one by using the GCLK as the
clock source. Now, depending on the error rate between
the desired baudrate and the actual baudrate, the serial driver will
fallback on the generic clock. The generic clock must be provided
in the DT node of the serial that may need a more flexible clock source.
Furthermore, define the bit that represents the choice of having GCLK
as a baudrate source clock inside the USCLKS bitmask of the Mode Register
of USART IP's.
Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
Link: https://lore.kernel.org/r/20220922113347.144383-9-sergiu.moga@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure that the driver only divides the clock divisor if the
IP handled at that point is USART, since UART IP's do not support
implicit peripheral clock division. Instead, in the case of UART,
go with the highest possible clock divisor.
Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220922113347.144383-8-sergiu.moga@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When clearing the mode of the serial IP inside the atmel_set_termios()
method, make sure that the difference between the bitfields placement
of the UART IP's and USART IP's is taken into account, as some of
them overlap with each other. For example, ATMEL_UA_BRSRCCK overlaps
with ATMEL_US_NBSTOP and ATMEL_US_USCLKS overlaps with ATMEL_UA_FILTER.
Furthermore, add definitions for the Baud Rate Source Clock and the
Filter bitfields of the Mode Register of UART IP's, since they were
missing.
Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
Link: https://lore.kernel.org/r/20220922113347.144383-7-sergiu.moga@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Invoking TIOCVHANGUP on 8250_mid port on Ice Lake-D and then reopening
the port triggers these faults during serial8250_do_startup():
DMAR: DRHD: handling fault status reg 3
DMAR: [DMA Write NO_PASID] Request device [00:1a.0] fault addr 0x0 [fault reason 0x05] PTE Write access is not set
If the IRQ hasn't been set up yet, the UART will have zeroes in its MSI
address/data registers. Disabling the IRQ at the interrupt controller
won't stop the UART from performing a DMA write to the address programmed
in its MSI address register (zero) when it wants to signal an interrupt.
The UARTs (in Ice Lake-D) implement PCI 2.1 style MSI without masking
capability, so there is no way to mask the interrupt at the source PCI
function level, except disabling the MSI capability entirely, but that
would cause it to fall back to INTx# assertion, and the PCI specification
prohibits disabling the MSI capability as a way to mask a function's
interrupt service request.
The MSI address register is zeroed by the hangup as the irq is freed.
The interrupt is signalled during serial8250_do_startup() performing a
THRE test that temporarily toggles THRI in IER. The THRE test currently
occurs before UART's irq (and MSI address) is properly set up.
Refactor serial8250_do_startup() such that irq is set up before the
THRE test. The current irq setup code is intermixed with the timer
setup code. As THRE test must be performed prior to the timer setup,
extract it into own function and call it only after the THRE test.
The ->setup_timer() needs to be part of the struct uart_8250_ops in
order to not create circular dependency between 8250 and 8250_base
modules.
Fixes: 40b36daad0 ("[PATCH] 8250 UART backup timer")
Reported-by: Lennert Buytenhek <buytenh@arista.com>
Tested-by: Lennert Buytenhek <buytenh@arista.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220922070005.2965-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Oxford Semiconductor PCIe (Tornado) 950 serial port devices need to
operate in the enhanced mode via the EFR register for the Divide-by-M
N/8 baud rate generator prescaler to be used in their native UART mode.
Otherwise the prescaler is fixed at 1 causing grossly incorrect baud
rates to be programmed.
Accessing the EFR register requires 16550A features to have been probed
for, so request this to happen regardless of SERIAL_8250_16550A_VARIANTS
by setting UPF_FULL_PROBE in port flags.
Fixes: 366f6c955d ("serial: 8250: Add proper clock handling for OxSemi PCIe devices")
Cc: stable@vger.kernel.org # v5.19+
Reported-by: Anders Blomdell <anders.blomdell@control.lth.se>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2209210005040.41633@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A SERIAL_8250_16550A_VARIANTS configuration option has been recently
defined that lets one request the 8250 driver not to probe for 16550A
device features so as to reduce the driver's device startup time in
virtual machines.
Some actual hardware devices require these features to have been fully
determined however for their driver to work correctly, so define a flag
to let drivers request full 16550A feature probing on a device-by-device
basis if required regardless of the SERIAL_8250_16550A_VARIANTS option
setting chosen.
Fixes: dc56ecb81a ("serial: 8250: Support disabling mdelay-filled probes of 16550A variants")
Cc: stable@vger.kernel.org # v5.6+
Reported-by: Anders Blomdell <anders.blomdell@control.lth.se>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2209202357520.41633@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This non-trivial code is doubled in transmit_chars(), so it deserves its
own function. This will make next patches easier.
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220920052049.20507-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mpc52xx_uart_int_rx_chars() returns unsigned int.
mpc52xx_uart_int_tx_chars() returns int.
The both results are binary ORed to the "keepgoing" variable. Unify all
three to bool as the only interesting value is whether we should keep
looping (true/false).
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220920052049.20507-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The condition in __serial_lpc32xx_tx()'s loop is barely readable.
Extract it to a separate function. This will make the cleanup in the
next patches easier too.
Cc: Vladimir Zapolskiy <vz@mleia.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220920052049.20507-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The condition in lqasc_tx_chars()'s loop is barely readable. Extract it
to a separate function. This will make the cleanup in the next patches
easier too.
(Put it before lqasc_start_tx(), so that we can use it there later.)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220920052049.20507-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Both altera_uart_{r,t}x_chars() need only uart_port, not altera_uart. So
pass the former from altera_uart_interrupt() directly.
Apart it maybe saves a dereference, this makes the transition of
altera_uart_tx_chars() easier to follow in the next patch.
Cc: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220920052049.20507-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "stop TX" path in altera_uart_tx_chars() is open-coded, so:
* use uart_circ_empty() to check if the buffer is empty, and
* when true, call altera_uart_stop_tx().
Cc: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220920052049.20507-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make vt8500_tx_empty() more readable by introducing a new local variable
and move the function before handle_tx(). That way we can reuse it in
there too.
Cc: <linux-arm-kernel@lists.infradead.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220920052049.20507-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This error path needs to unwind instead of just returning directly.
Fixes: 03a8482c17 ("drivers: serial: jsm: Enable support for Digi Classic adapters")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YyxFh1+lOeZ9WfKO@kili
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The serial-omap driver requires an rts-gpio for RS-485 to work.
Historically it has allowed enabling RS-485 even if no rts-gpio was
specified in the device tree.
That doesn't make any sense, so disable RS-485 on probe if rts-gpio is
missing and disallow user space from enabling it.
Three NULL pointer checks for up->rts_gpiod can be dropped as a result,
simplifying the driver slightly.
Cc: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/f191dcca0d8ea03598c463fc0d3fba8941ff2275.1662888075.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A debug bit to output a complete transmission dump exists. Sometimes only
the user frames are relevant. Add an additional bit which limits the
transmission dump output to user data frames if set.
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220831073800.7459-6-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce defines to name the various debug bits used within the code to
improve readability and to make its specific use clear.
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220831073800.7459-5-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
