This reverts commit 679193b7ba.
It appears that in QEmu the lock has been initialised differently
(it wasn't obvious on real hardware during testing). Let's
revert the change until the better approach will be developed.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200802111612.36189-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the serial core handles spin lock initialisation,
let the driver rely on it.
Depends-on: f743061a85 ("serial: core: Initialise spin lock before use in uart_configure_port()")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200731123733.22754-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is very unlikely for processor to speculate on the func_table index.
The index is uchar and func_table is of size 256. So the compiler would
need to screw up and generate a really bad code.
But to stay on the safe side, forbid speculation on this user passed
index.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Jiri Kosina <jikos@kernel.org>
Link: https://lore.kernel.org/r/20200730105546.24268-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This converts all the existing DECLARE_TASKLET() (and ...DISABLED)
macros with DECLARE_TASKLET_OLD() in preparation for refactoring the
tasklet callback type. All existing DECLARE_TASKLET() users had a "0"
data argument, it has been removed here as well.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
While the STM32 does support RS485 drive-enable control within the
UART IP itself, some systems have the drive-enable line connected
to a pin which cannot be pinmuxed as RTS. Add support for toggling
the RTS GPIO line using the modem control GPIOs to provide at least
some sort of emulation.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Cc: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-stm32@st-md-mailman.stormreply.com
Link: https://lore.kernel.org/r/20200725144947.537007-1-marex@denx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The race condition may happen if the UART reference clock is shared with
some other device (on Baikal-T1 SoC it's another DW UART port). In this
case if that device changes the clock rate while serial console is using
it the DW 8250 UART port might not only end up with an invalid uartclk
value saved, but may also experience a distorted output data since
baud-clock could have been changed. In order to fix this lets at least
try to adjust the 8250 port setting like UART clock rate in case if the
reference clock rate change is discovered. The driver will call the new
method to update 8250 UART port clock rate settings. It's done by means of
the clock event notifier registered at the port startup and unregistered
in the shutdown callback method.
Note 1. In order to avoid deadlocks we had to execute the UART port update
method in a dedicated deferred work. This is due to (in my opinion
redundant) the clock update implemented in the dw8250_set_termios()
method.
Note 2. Before the ref clock is manually changed by the custom
set_termios() function we swap the port uartclk value with new rate
adjusted to be suitable for the requested baud. It is necessary in
order to effectively disable a functionality of the ref clock events
handler for the current UART port, since uartclk update will be done
a bit further in the generic serial8250_do_set_termios() function.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200723003357.26897-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Indeed according to the clk API if clk_round_rate() has successfully
accepted a rate, then in order setup the clock with value returned by the
clk_round_rate() the clk_set_rate() method must be called with the
original rate value.
Suggested-by: Russell King <linux@armlinux.org.uk>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200723003357.26897-4-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Really instead of twice checking the clk_round_rate() return value
we could do it once, and if it isn't error the clock rate can be changed.
By doing so we decrease a number of ret-value tests and remove a weird
goto-based construction implemented in the dw8250_set_termios() method.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200723003357.26897-3-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some platforms can be designed in a way so the UART port reference clock
might be asynchronously changed at some point. In Baikal-T1 SoC this may
happen due to the reference clock being shared between two UART ports, on
the Allwinner SoC the reference clock is derived from the CPU clock, so
any CPU frequency change should get to be known/reflected by/in the UART
controller as well. But it's not enough to just update the
uart_port->uartclk field of the corresponding UART port, the 8250
controller reference clock divisor should be altered so to preserve
current baud rate setting. All of these things is done in a coherent
way by calling the serial8250_update_uartclk() method provided in this
patch. Though note that it isn't supposed to be called from within the
UART port callbacks because the locks using to the protect the UART port
data are already taken in there.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200723003357.26897-2-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Split imx earlycon driver from imx serial driver "imx.c" as
separated driver. imx serial driver can be built as module,
but earlycon driver only support build in.
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Link: https://lore.kernel.org/r/20200724070815.11445-3-fugang.duan@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for building i.MX serial driver as module.
The changes of the patch:
- imx console driver can be built as module.
- move out earlycon code to separated driver like imx_earlycon.c,
and imx earlycon driver only support build-in.
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Link: https://lore.kernel.org/r/20200724070815.11445-2-fugang.duan@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 1355cba9c3 ("tty/synclink: remove ISA support"), the
synlink driver only supports PCI card. Remove any leftover dead code
to support other cards.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20200727130501.31005-1-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the preferred form for passing the size of a structure type. The
alternative form where the structure type is spelled out hurts
readability and introduces an opportunity for a bug when the object
type is changed but the corresponding object identifier to which the
sizeof operator is applied is not.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/b04dd8cdd67bd6ffde3fd12940aeef35fdb824a6.1595543280.git.gustavoars@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix the following checkpatch.pl warnings together with all the
identation issues in struct serial_struct32:
ERROR: code indent should use tabs where possible
+ char reserved_char;$
WARNING: please, no spaces at the start of a line
+ char reserved_char;$
ERROR: code indent should use tabs where possible
+ compat_int_t reserved;$
WARNING: please, no spaces at the start of a line
+ compat_int_t reserved;$
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/77576843397aeab0af8aa0423a9768f3ca8dedfb.1595543280.git.gustavoars@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge 5.8-rc7 into tty-next
we need the tty/serial fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sealevel XR17V35X based devices are inoperable on kernel versions
4.11 and above due to a change in the GPIO preconfiguration introduced in
commit
7dea8165f1. This patch fixes this by preconfiguring the GPIO on Sealevel
cards to the value (0x00) used prior to commit 7dea8165f1
With GPIOs preconfigured as per commit 7dea8165f1 all ports on
Sealevel XR17V35X based devices become stuck in high impedance
mode, regardless of dip-switch or software configuration. This
causes the device to become effectively unusable. This patch (in
various forms) has been distributed to our customers and no issues
related to it have been reported.
Fixes: 7dea8165f1 ("serial: exar: Preconfigure xr17v35x MPIOs as output")
Signed-off-by: Matthew Howell <matthew.howell@sealevel.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2007221605270.13247@tstest-VirtualBox
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add sparse context annotation to the receive handlers, which release and
reacquire the port lock, to silence sparse warnings:
drivers/tty/serial/msm_serial.c:748:25: warning: context imbalance in 'msm_handle_rx_dm' - unexpected unlock
drivers/tty/serial/msm_serial.c:814:28: warning: context imbalance in 'msm_handle_rx' - unexpected unlock
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723123327.5843-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add sparse context annotation to the receive handler, which releases and
reacquires the port lock, to silence a sparse warning:
drivers/tty/serial/pmac_zilog.c:255:36: sparse: sparse: context imbalance in 'pmz_receive_chars' - unexpected unlock
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723123327.5843-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 7b668c064e ("serial: 8250: Fix max baud limit in generic 8250
port") fixed limits of a baud rate setting for a generic 8250 port.
In other words since that commit the baud rate has been permitted to be
within [uartclk / 16 / UART_DIV_MAX; uartclk / 16], which is absolutely
normal for a standard 8250 UART port. But there are custom 8250 ports,
which provide extended baud rate limits. In particular the Mediatek 8250
port can work with baud rates up to "uartclk" speed.
Normally that and any other peculiarity is supposed to be handled in a
custom set_termios() callback implemented in the vendor-specific
8250-port glue-driver. Currently that is how it's done for the most of
the vendor-specific 8250 ports, but for some reason for Mediatek a
solution has been spread out to both the glue-driver and to the generic
8250-port code. Due to that a bug has been introduced, which permitted the
extended baud rate limit for all even for standard 8250-ports. The bug
has been fixed by the commit 7b668c064e ("serial: 8250: Fix max baud
limit in generic 8250 port") by narrowing the baud rates limit back down to
the normal bounds. Unfortunately by doing so we also broke the
Mediatek-specific extended bauds feature.
A fix of the problem described above is twofold. First since we can't get
back the extended baud rate limits feature to the generic set_termios()
function and that method supports only a standard baud rates range, the
requested baud rate must be locally stored before calling it and then
restored back to the new termios structure after the generic set_termios()
finished its magic business. By doing so we still use the
serial8250_do_set_termios() method to set the LCR/MCR/FCR/etc. registers,
while the extended baud rate setting procedure will be performed later in
the custom Mediatek-specific set_termios() callback. Second since a true
baud rate is now fully calculated in the custom set_termios() method we
need to locally update the port timeout by calling the
uart_update_timeout() function. After the fixes described above are
implemented in the 8250_mtk.c driver, the Mediatek 8250-port should
get back to normally working with extended baud rates.
Link: https://lore.kernel.org/linux-serial/20200701211337.3027448-1-danielwinkler@google.com
Fixes: 7b668c064e ("serial: 8250: Fix max baud limit in generic 8250 port")
Reported-by: Daniel Winkler <danielwinkler@google.com>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: stable <stable@vger.kernel.org>
Tested-by: Claire Chang <tientzu@chromium.org>
Link: https://lore.kernel.org/r/20200714124113.20918-1-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch imitates 6e0a5de213 ("serial: 8250: Use hrtimers for
rs485 delays") in replacing the previously used classic timers
with hrtimers. The old way provided a too coarse resolution on
systems with configs of less than 1000 HZ.
Use of hrtimers addresses this and can be easily extended to
support microsecond resolution in future when support
for this arrives upstream.
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Link: https://lore.kernel.org/r/20200714093012.21621-3-uwe@kleine-koenig.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds support for delays between assertion of RTS (which is supposed
to enable the rs485 transmitter) and sending as well as between the last
send char and deassertionof RTS.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20200714093012.21621-2-uwe@kleine-koenig.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The struct tty_port is part of the uart state and will never be NULL in
the receive helpers. Drop the bogus NULL checks and rename the
pointer-variables "port" to differentiate them from struct tty_struct
pointers (which can be NULL).
Fixes: 962963e4ee ("serial: tegra: Switch to using struct tty_port")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200710135947.2737-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 33ae787b74 ("serial: tegra: add support to ignore read") added
support for dropping input in case CREAD isn't set, but for PIO the
ignore_status_mask wasn't checked until after the character had been
put in the receive buffer.
Note that the NULL tty-port test is bogus and will be removed by a
follow-on patch.
Fixes: 33ae787b74 ("serial: tegra: add support to ignore read")
Cc: stable <stable@vger.kernel.org> # 5.4
Cc: Shardar Shariff Md <smohammed@nvidia.com>
Cc: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200710135947.2737-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers using legacy PM have to manage PCI states and device's PM states
themselves. They also need to take care of configuration registers.
With improved and powerful support of generic PM, PCI Core takes care of
above mentioned, device-independent, jobs.
This driver makes use of PCI helper functions like
pci_save/restore_state(), pci_enable_device() and pci_set_power_state()
to do required operations. In generic mode, they are no longer needed.
Change function parameter in both .suspend() and .resume() to
"struct device*" type. Use dev_get_drvdata() to get drv data.
Compile-tested only.
Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Link: https://lore.kernel.org/r/20200720120414.399961-1-vaibhavgupta40@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Link: https://lore.kernel.org/r/20200718103018.3164-1-grandmaster@al2klimov.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes the following checkpatch error and warning:
1. space required after ','
2. Missing a blank line after declarations
Signed-off-by: Tamseel Shams <m.shams@samsung.com>
Link: https://lore.kernel.org/r/20200716115438.9967-1-m.shams@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200718100807.983-1-grandmaster@al2klimov.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200718123840.19957-1-grandmaster@al2klimov.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200718133452.24290-1-grandmaster@al2klimov.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit f38278e9b8.
There has been a quick fix against uninitialised lock revealed by
the commit f743061a85 ("serial: core: Initialise spin lock before use
in uart_configure_port()"). Since we have now better fix in serial core,
this may be safely reverted.
Fixes: f38278e9b8 ("serial: sh-sci: Initialize spinlock for uart console")
Depends-on: f743061a85 ("serial: core: Initialise spin lock before use in uart_configure_port()")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200711135346.71171-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 8f065acec7.
There has been a quick fix against uninitialised lock revealed by
the commit f743061a85 ("serial: core: Initialise spin lock before use
in uart_configure_port()"). Since we have now better fix in serial core,
this may be safely reverted.
Fixes: 8f065acec7 ("serial: imx: Initialize lock for non-registered console")
Depends-on: f743061a85 ("serial: core: Initialise spin lock before use in uart_configure_port()")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200711135346.71171-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 17b4efdf4e.
There has been a quick fix against uninitialised lock revealed by
the commit f743061a85 ("serial: core: Initialise spin lock before use
in uart_configure_port()"). Since we have now better fix in serial core,
this may be safely reverted.
Fixes: 17b4efdf4e ("tty: serial: add missing spin_lock_init for SiFive serial console")
Depends-on: f743061a85 ("serial: core: Initialise spin lock before use in uart_configure_port()")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200711135346.71171-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 8508f4cba3.
There has been a quick fix against uninitialised lock revealed by
the commit f743061a85 ("serial: core: Initialise spin lock before use
in uart_configure_port()"). Since we have now better fix in serial core,
this may be safely reverted.
Fixes: 8508f4cba3 ("serial: amba-pl011: Make sure we initialize the port.lock spinlock")
Depends-on: f743061a85 ("serial: core: Initialise spin lock before use in uart_configure_port()")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200711135346.71171-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 0f87aa66e8.
There has been a quick fix against uninitialised lock revealed by
the commit f743061a85 ("serial: core: Initialise spin lock before use
in uart_configure_port()"). Since we have now better fix in serial core,
this may be safely reverted.
Fixes: 0f87aa66e8 ("serial: sunhv: Initialize lock for non-registered console")
Depends-on: f743061a85 ("serial: core: Initialise spin lock before use in uart_configure_port()")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200711135346.71171-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The problems started with the revert (18cc7ac8a2). The
cdns_uart_console.index is statically assigned -1. When the port is
registered, Linux assigns consecutive numbers to it. It turned out that
when using ttyPS1 as console, the index is not updated as we are reusing
the same cdns_uart_console instance for multiple ports. When registering
ttyPS0, it gets updated from -1 to 0, but when registering ttyPS1, it
already is 0 and not updated.
That led to 2ae11c46d5. It assigns the index prior to registering
the uart_driver once. Unfortunately, that ended up breaking the
situation where the probe order does not match the id order. When using
the same device tree for both uboot and linux, it is important that the
serial0 alias points to the console. So some boards reverse those
aliases. This was reported by Jan Kiszka. The proposed fix was reverting
the index assignment and going back to the previous iteration.
However such a reversed assignement (serial0 -> uart1, serial1 -> uart0)
was already partially broken by the revert (18cc7ac8a2). While the
ttyPS device works, the kmsg connection is already broken and kernel
messages go missing. Reverting the id assignment does not fix this.
>From the xilinx_uartps driver pov (after reverting the refactoring
commits), there can be only one console. This manifests in static
variables console_pprt and cdns_uart_console. These variables are not
properly linked and can go out of sync. The cdns_uart_console.index is
important for uart_add_one_port. We call that function for each port -
one of which hopefully is the console. If it isn't, the CON_ENABLED flag
is not set and console_port is cleared. The next cdns_uart_probe call
then tries to register the next port using that same cdns_uart_console.
It is important that console_port and cdns_uart_console (and its index
in particular) stay in sync. The index assignment implemented by
Shubhrajyoti Datta is correct in principle. It just may have to happen a
second time if the first cdns_uart_probe call didn't encounter the
console device. And we shouldn't change the index once the console uart
is registered.
Reported-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Reported-by: Jan Kiszka <jan.kiszka@web.de>
Link: https://lore.kernel.org/linux-serial/f4092727-d8f5-5f91-2c9f-76643aace993@siemens.com/
Fixes: 18cc7ac8a2 ("Revert "serial: uartps: Register own uart console and driver structures"")
Fixes: 2ae11c46d5 ("tty: xilinx_uartps: Fix missing id assignment to the console")
Fixes: 76ed2e1057 ("Revert "tty: xilinx_uartps: Fix missing id assignment to the console"")
Signed-off-by: Helmut Grohne <helmut.grohne@intenta.de>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200713073227.GA3805@laureti-dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
syzbot is reporting general protection fault in do_con_write() [1] caused
by vc->vc_screenbuf == ZERO_SIZE_PTR caused by vc->vc_screenbuf_size == 0
caused by vc->vc_cols == vc->vc_rows == vc->vc_size_row == 0 caused by
fb_set_var() from ioctl(FBIOPUT_VSCREENINFO) on /dev/fb0 , for
gotoxy(vc, 0, 0) from reset_terminal() from vc_init() from vc_allocate()
from con_install() from tty_init_dev() from tty_open() on such console
causes vc->vc_pos == 0x10000000e due to
((unsigned long) ZERO_SIZE_PTR) + -1U * 0 + (-1U << 1).
I don't think that a console with 0 column or 0 row makes sense. And it
seems that vc_do_resize() does not intend to allow resizing a console to
0 column or 0 row due to
new_cols = (cols ? cols : vc->vc_cols);
new_rows = (lines ? lines : vc->vc_rows);
exception.
Theoretically, cols and rows can be any range as long as
0 < cols * rows * 2 <= KMALLOC_MAX_SIZE is satisfied (e.g.
cols == 1048576 && rows == 2 is possible) because of
vc->vc_size_row = vc->vc_cols << 1;
vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
in visual_init() and kzalloc(vc->vc_screenbuf_size) in vc_allocate().
Since we can detect cols == 0 or rows == 0 via screenbuf_size = 0 in
visual_init(), we can reject kzalloc(0). Then, vc_allocate() will return
an error, and con_write() will not be called on a console with 0 column
or 0 row.
We need to make sure that integer overflow in visual_init() won't happen.
Since vc_do_resize() restricts cols <= 32767 and rows <= 32767, applying
1 <= cols <= 32767 and 1 <= rows <= 32767 restrictions to vc_allocate()
will be practically fine.
This patch does not touch con_init(), for returning -EINVAL there
does not help when we are not returning -ENOMEM.
[1] https://syzkaller.appspot.com/bug?extid=017265e8553724e514e8
Reported-and-tested-by: syzbot <syzbot+017265e8553724e514e8@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200712111013.11881-1-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge 5.8-rc6 into tty-next
We need the serial/tty fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.
In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:
git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
xargs perl -pi -e \
's/\buninitialized_var\(([^\)]+)\)/\1/g;
s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'
drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.
No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.
[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/
Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
Here are some small tty and serial driver fixes for 5.8-rc6.
The largest set of patches in here is a revert of the sysrq changes that
went into 5.8-rc1 but turned out to cause a noticable overhead and cpu
usage.
Other than that, there's a few small serial driver fixes to resolve
reported issues, and finally resolving the spinlock init problem on many
serial driver consoles.
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-5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty into master
Pull tty/serial driver fixes from Greg KH:
:Here are some small tty and serial driver fixes for 5.8-rc6.
The largest set of patches in here is a revert of the sysrq changes
that went into 5.8-rc1 but turned out to cause a noticable overhead
and cpu usage.
Other than that, there's a few small serial driver fixes to resolve
reported issues, and finally resolving the spinlock init problem on
many serial driver consoles.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: core: Initialise spin lock before use in uart_configure_port()
serial: mxs-auart: add missed iounmap() in probe failure and remove
serial: sh-sci: Initialize spinlock for uart console
Revert "tty: xilinx_uartps: Fix missing id assignment to the console"
serial: core: drop redundant sysrq checks
serial: core: fix sysrq overhead regression
Revert "serial: core: Refactor uart_unlock_and_check_sysrq()"
tty/serial: fix serial_core.c kernel-doc warnings
tty: serial: cpm_uart: Fix behaviour for non existing GPIOs
When using the geni-serial as console, its important to be
able to hit the lowest possible power state in suspend,
even with no_console_suspend.
The only thing that prevents it today on platforms like the sc7180
is the interconnect BW votes, which we certainly don't need when
the system is in suspend. So in the suspend handler mark them as
ACTIVE_ONLY (0x3) and on resume switch them back to the ALWAYS tag (0x7)
Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Reviewed-by: Akash Asthana <akashast@codeaurora.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/1594704709-26072-1-git-send-email-rnayak@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
The geni serial driver had a rule that we'd only use 1 byte per FIFO
word for the TX FIFO if we were being used for the serial console.
This is ugly and a bit of a pain. It's not too hard to fix, so fix
it.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200626125844.2.Iabd56347670b9e4e916422773aba5b27943d19ee@changeid
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
The geni serial driver had the rather sketchy hack in it where it
would adjust the number of bytes per RX FIFO word from 4 down to 1 if
it detected that CONFIG_CONSOLE_POLL was enabled (for kgdb) and this
was a console port (defined by the kernel directing output to this
port via the "console=" command line argument).
The problem with that sketchy hack is that it's possible to run kgdb
over a serial port even if it isn't used for console.
Let's avoid the hack by simply handling the 4-bytes-per-FIFO word case
for kdb. We'll have to have a (very small) cache but that should be
fine.
A nice side effect of this patch is that an agetty (or similar)
running on this port is less likely to drop characters. We'll
have roughly 4 times the RX FIFO depth than we used to now.
NOTE: the character cache here isn't shared between the polling API
and the non-polling API. That means that, technically, the polling
API could eat a few extra bytes. This doesn't seem to pose a huge
problem in reality because we'll only get several characters per FIFO
word if those characters are all received at nearly the same time and
we don't really expect non-kgdb characters to be sent to the same port
as kgdb at the exact same time we're exiting kgdb.
ALSO NOTE: we still have the sketchy hack for setting the number of
bytes per TX FIFO word in place, but that one is less bad. kgdb
doesn't have any problem with this because it always just sends 1 byte
at a time and waits for it to finish. The TX FIFO hack is only really
needed for console output. In any case, a future patch will remove
that hack, too.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200626125844.1.I8546ecb6c5beb054f70c5302d1a7293484212cd1@changeid
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
The comment near to uart_port_spin_lock_init() says:
Ensure that the serial console lock is initialised early.
If this port is a console, then the spinlock is already initialised.
and there is nothing about enabled or disabled consoles. The commit
a3cb39d258 ("serial: core: Allow detach and attach serial device
for console") made a change, which follows the comment, and also to
prevent reinitialisation of the lock in use, when user detaches and
attaches back the same console device. But this change discovers
another issue, that uart_add_one_port() tries to access a spin lock
that now may be uninitialised. This happens when a driver expects
the serial core to register a console on its behalf. In this case
we must initialise a spin lock before use.
Fixes: a3cb39d258 ("serial: core: Allow detach and attach serial device for console")
Reported-by: Marc Zyngier <maz@kernel.org>
Reported-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Anatoly Pugachev <matorola@gmail.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20200706214903.56148-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This driver calls ioremap() in probe, but it misses calling iounmap() in
probe's error handler and remove.
Add the missed calls to fix it.
Fixes: 47d37d6f94 ("serial: Add auart driver for i.MX23/28")
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200709135608.68290-1-hslester96@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty TIOCL_SETSEL ioctl allocates a memory buffer big enough for text
selection area. The maximum allowed console size is
VC_RESIZE_MAXCOL * VC_RESIZE_MAXROW == 32767*32767 == ~1GB and typical
MAX_ORDER is set to allow allocations lot less than than (circa 16MB).
So it is quite possible to trigger huge allocation (and syzkaller just
did that) which is going to fail (which is fine) with a backtrace in
mm/page_alloc.c at WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN)) and
this may trigger panic (if panic_on_warn is enabled) and
leak kernel addresses to dmesg.
This passes __GFP_NOWARN to kmalloc_array to avoid unnecessary user-
triggered WARN_ON. Note that the error is not ignored and
the warning is still printed.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Link: https://lore.kernel.org/r/20200617070444.116704-1-aik@ozlabs.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support of generic DT binding for annoucing RTS/CTS lines. The initial
binding 'st,hw-flow-control' is not needed anymore since generic binding
is available, but is kept for backward compatibility.
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>
Link: https://lore.kernel.org/r/20200520133932.30441-3-erwan.leray@st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 2ae11c46d5.
It turned out to break the ultra96-rev1, e.g., which uses uart1 as
serial0 (and stdout-path = "serial0:115200n8").
Fixes: 2ae11c46d5 ("tty: xilinx_uartps: Fix missing id assignment to the console")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/f4092727-d8f5-5f91-2c9f-76643aace993@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 8e20fc3917 ("serial_core: Move sysrq functions from header
file") converted the inline sysrq helpers to exported functions which
are now called for every received character, interrupt and break signal
also on systems without CONFIG_MAGIC_SYSRQ_SERIAL instead of being
optimised away by the compiler.
Inlining these helpers again also avoids the function call overhead when
CONFIG_MAGIC_SYSRQ_SERIAL is enabled (e.g. when the port is not used as
a console).
Fixes: 8e20fc3917 ("serial_core: Move sysrq functions from header file")
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://lore.kernel.org/r/20200610152232.16925-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit da9a5aa340.
In order to ease backporting a fix for a sysrq regression, revert this
rewrite which was since added on top.
The other sysrq helpers now bail out early when sysrq is not enabled;
it's better to keep that pattern here as well.
Note that the __releases() attribute won't be needed after the follow-on
fix either.
Fixes: da9a5aa340 ("serial: core: Refactor uart_unlock_and_check_sysrq()")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200610152232.16925-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
platform_get_irq() provides an established error code and error message.
Also, it's better to use dedicated API to retrieve Linux IRQ resource.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/20200618122952.88265-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
platform_get_irq() provides an established error code and error message.
Also, it's better to use dedicated API to retrieve Linux IRQ resource.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200618123320.88612-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
platform_get_irq() provides an established error code and error message.
Also, it's better to use dedicated API to retrieve Linux IRQ resource.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200618122744.88204-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
platform_get_irq() provides an established error code and error message.
Also, it's better to use dedicated API to retrieve Linux IRQ resource.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200618122024.87170-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
platform_get_irq() provides an established error code and error message.
Also, it's better to use dedicated API to retrieve Linux IRQ resource.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200618095144.73852-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit a4912303ac ("serial: kgdboc: Allow earlycon initialization
to be deferred") it looks like Daniel really took Linus's new
suggestion about not needing to wrap at 80 columns to heart and he
jammed two full lines of comments into one line. Either that or he
just somehow accidentally deleted a carriage return when doing final
edits on the patch. In either case let's make it look prettier.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200602124044.1.Iee31247bc080d42a02e167454b1225a1b4283705@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since dev_err() calls can lead to synchronous writes to another serial
console these calls can provide significant latency during irq-handling
in tegra_uart_isr(). With this latency another interrupt is likely to
apper during handling of the first interrupt, which might lock up the
kernel completely.
These errors are reported to the error counters so converting the
dev_err() to dev_dbg() is appropriate.
Signed-off-by: Randolph Maaßen <gaireg@gaireg.de>
Link: https://lore.kernel.org/r/20200605145714.9964-1-gaireg@gaireg.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
get_num_ports returns -ENODEV, and the result is stored in int, so it
should not be unsigned. Zero ports does not seem to make sense, so
make that check consistent.
Signed-off-by: Pavel Machek (CIP) <pavel@denx.de>
Link: https://lore.kernel.org/r/20200606151146.GA10940@amd
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drop the recently added gpio include from the serial-core header in
favour of a forward declaration and instead include the gpio header only
where needed.
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20200610155121.14014-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The formula for the baud rate is
baud rate = "baud clock / ((OSR+1) × SBR)
Algorithm used in function lpuart32_serial_setbrg() only changes
the SBR. Even with maxmum value put in, OSR stays at 0x7 and the
lowest baud rate would be ~ 2600 bps
Update the algorithm to allow driver operation at 1200,2400 or 600 bps
Signed-off-by: Vabhav Sharma <vabhav.sharma@nxp.com>
Link: https://lore.kernel.org/r/1593170434-13524-1-git-send-email-vabhav.sharma@oss.nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ARRAY_SIZE() is the number of elements but we want the number of
bytes so sizeof() is more appropriate. Fortunately, it's the same
thing here because this is an array of u8 so this doesn't change
runtime.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200624132744.GD9972@mwanda
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
devm_gpiod_get_index() doesn't return NULL but -ENOENT when the
requested GPIO doesn't exist, leading to the following messages:
[ 2.742468] gpiod_direction_input: invalid GPIO (errorpointer)
[ 2.748147] can't set direction for gpio #2: -2
[ 2.753081] gpiod_direction_input: invalid GPIO (errorpointer)
[ 2.758724] can't set direction for gpio #3: -2
[ 2.763666] gpiod_direction_output: invalid GPIO (errorpointer)
[ 2.769394] can't set direction for gpio #4: -2
[ 2.774341] gpiod_direction_input: invalid GPIO (errorpointer)
[ 2.779981] can't set direction for gpio #5: -2
[ 2.784545] ff000a20.serial: ttyCPM1 at MMIO 0xfff00a20 (irq = 39, base_baud = 8250000) is a CPM UART
Use devm_gpiod_get_index_optional() instead.
At the same time, handle the error case and properly exit
with an error.
Fixes: 97cbaf2c82 ("tty: serial: cpm_uart: Convert to use GPIO descriptors")
Cc: stable@vger.kernel.org
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/694a25fdce548c5ee8b060ef6a4b02746b8f25c0.1591986307.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a spelling mistake in a comment. Fix it.
Signed-off-by: Tamseel Shams <m.shams@samsung.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Link: https://lore.kernel.org/r/20200617105907.7143-1-m.shams@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make the code slightly more readable by removing unneeded line breaks,
adding missing line breaks and white spaces. This also fixes few strict
checkpatch suggestions:
CHECK: spaces preferred around that '-' (ctx:VxV)
CHECK: Unbalanced braces around else statement
CHECK: Lines should not end with a '('
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200617152856.18086-1-krzk@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In kgdb context, calling console handlers aren't safe due to locks used
in those handlers which could in turn lead to a deadlock. Although, using
oops_in_progress increases the chance to bypass locks in most console
handlers but it might not be sufficient enough in case a console uses
more locks (VT/TTY is good example).
Currently when a driver provides both polling I/O and a console then kdb
will output using the console. We can increase robustness by using the
currently active polling I/O driver (which should be lockless) instead
of the corresponding console. For several common cases (e.g. an
embedded system with a single serial port that is used both for console
output and debugger I/O) this will result in no console handler being
used.
In order to achieve this we need to reverse the order of preference to
use dbg_io_ops (uses polling I/O mode) over console APIs. So we just
store "struct console" that represents debugger I/O in dbg_io_ops and
while emitting kdb messages, skip console that matches dbg_io_ops
console in order to avoid duplicate messages. After this change,
"is_console" param becomes redundant and hence removed.
Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/1591264879-25920-5-git-send-email-sumit.garg@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Use the 'common' foo_console_setup() naming scheme. There are 71
foo_console_setup() callbacks and only one foo_setup_console().
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200619172240.754910-1-sergey.senozhatsky@gmail.com
For unifying console ->setup() handling, which is poorly documented,
return error code, rather than non-zero arbitrary number.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200618164751.56828-5-andriy.shevchenko@linux.intel.com
For unifying console ->setup() handling, which is poorly documented,
return error code, rather than non-zero arbitrary number.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200618164751.56828-4-andriy.shevchenko@linux.intel.com
For unifying console ->setup() handling, which is poorly documented,
return error code, rather than non-zero arbitrary number.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200618164751.56828-3-andriy.shevchenko@linux.intel.com
geni serial needs to express a perforamnce state requirement on CX
powerdomain depending on the frequency of the clock rates.
Use OPP table from DT to register with OPP framework and use
dev_pm_opp_set_rate() to set the clk/perf state.
Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Akash Asthana <akashast@codeaurora.org>
Cc: linux-serial@vger.kernel.org
Link: https://lore.kernel.org/r/1592222564-13556-2-git-send-email-rnayak@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Get the interconnect paths for Uart based Serial Engine device
and vote according to the baud rate requirement of the driver.
Signed-off-by: Akash Asthana <akashast@codeaurora.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/1592908737-7068-5-git-send-email-akashast@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
QUP core clock is shared among all the SE drivers present on particular
QUP wrapper, the system will reset(unclocked access) if earlycon used after
QUP core clock is put to 0 from other SE drivers before real console comes
up.
As earlycon can't vote for it's QUP core need, to fix this add ICC
support to common/QUP wrapper driver and put vote for QUP core from
probe on behalf of earlycon and remove vote during earlycon exit call.
Signed-off-by: Akash Asthana <akashast@codeaurora.org>
Reported-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Link: https://lore.kernel.org/r/1592908737-7068-3-git-send-email-akashast@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
We can also thaw non-block file systems. Remove the CONFIG_BLOCK in
sysrq.c after making the prototype available unconditionally.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The vmemdup_user() function has no 2-factor argument form. Use array_size()
to check for the overflow.
Signed-off-by: Denis Efremov <efremov@linux.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200603102804.2110817-1-efremov@linux.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Synchronize with others and check perm directly in vt_k_ioctl.
We do not need to pass perm to do_fontx_ioctl and do_unimap_ioctl then.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-38-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We create a new vt_io_ioctl here and move there all the IO ioctls. This
makes vt_ioctl significantly smaller.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-32-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We create a new vt_k_ioctl here and move there all the K* ioctls. This
makes vt_ioctl significantly smaller.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-31-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
They were used for the first parameter of put_user. But put_user accepts
constants in the parameter and also determines the type only by the
second parameter. So we can safely drop these helpers and simplify the
code a bit.
Including the removal of set_int label.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-30-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is still a leftover from BKL, when we locked it around vt_ioctl's
code. We can return instead of breaks in the switch loop. And we can
return in case of errors too. This allows for sifting of the code to the
left in some cases.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-29-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All the attributes are bools, so do a simple shift instead of tests and
constants as bool is either 0 or 1.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-28-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There were too many parentheses in invert_screen, remove them and align
the code in invert_screen a bit.
No functional change intended.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-27-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The cursor code used to use magic constants, ANDs, ORs, and some macros.
Redefine all this to make some sense.
In particular:
* Drop CUR_DEFAULT, which is CUR_UNDERLINE. CUR_DEFAULT was used only
for cur_default variable initialization, so use CUR_UNDERLINE there to
make obvious what's the default.
* Drop CUR_HWMASK. Instead, define CUR_SIZE() which explains it more.
And use it all over the places.
* Define few more masks and bits which will be used in next patches
instead of magic constants.
* Define CUR_MAKE to build up cursor value.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-fbdev@vger.kernel.org
Link: https://lore.kernel.org/r/20200615074910.19267-25-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Format add_softcursor according to CodingStyle. Until now, it was a mess
of letters.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-24-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All the types are unsinged ints -- even the vpar passed to the function.
So unify them and use min() to compute count instead of explicit
comparison.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-23-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nested ternary operators spread over 4 lines are really evil for
reading. Turn the outer one to proper 'if'. Now, we see, there is a
common path, so the code can be simplified. This way, the code is
understandable now.
Checked using symbolic execution (klee), that the old and new behaviors
are the same.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-22-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Invert the attribute on the only place, without the need of checking
'inverse'.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-21-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert (!(A && !B) || C) into (!A || B || C) to improve readability.
No functional changes, as was just proven by objdump.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-20-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vc_con_write_normal now handles the complex normal characters
processing. It is no longer a part of do_con_write. So this patch makes
do_con_write pretty clean and obvious.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-19-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move the control characters detection to a separate function dubbed
vc_is_control. It makes the 14 subexpressions a "bit" more readable. And
also simplifies next patches.
It moves also CTRL_ACTION and CTRL_ALWAYS to this new function, as they
are used exclusively here. While at it, these are converted to static
const variables.
And we use "& BIT()" instead of ">>" and "& 1".
Checked using symbolic execution (klee), that the old and new
behaviors are the same.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-18-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that we reordered the code and the label, we can eliminate the
translation into a separate function. We call it vc_translate here.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-16-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This removes duplicated initialization of variables (after reordering
'c' initialization).
It will also allow for eliminating whole translation into a separate
function in the next patch.
Note that vc_state, vc_utf etc. are checked with every rescan now. But
they are immutable for non-control characters where rescan might be
only necessary.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-15-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We continue cleaning up do_con_write. This (hopefully) makes the
inversion code obvious.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-14-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code was too overcomplicated. Extract vc_sanitize_unicode to a
separate function and flatten the code. I believe the code is
straightforward now.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-13-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
do_con_write is complicated enough. Extract unicode handling to a
separate function. For do_con_write, 249 LOCs lowered to 183 lines.
Use diff -w -b to see the difference is neligible -- mostly whitespace
and use of 'return's instead of 'continue's.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-12-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use bools for rescan and inverse. And true/false accordingly.
Use u8 for width instead of uint8_t.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-11-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vc_translate is used only in vt.c, so move the definition from a header
there. Also, it used to be a macro, so be modern and make a static
inline from it. This makes the code actually readable.
And as a preparation for next patches, rename it to vc_translate_ascii.
vc_translate will be a wrapper for both unicode and this one.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-10-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
VT100ID is unused, but defined twice. Kill it.
VT102ID is used only in respond_ID. Define there a variable with proper
type and use that instead. Then drop both defines of VT102ID too.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pass the length of a string to respond_string and use
tty_insert_flip_string instead of a loop with tty_insert_flip_char. This
simplifies the processing on the tty side.
The added strlens are optimized during constant folding and propagation
and the result are proper constants in assembly.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vc_tab_stop is used as a bitmap, but defined as an unsigned int array.
Switch it to bitmap and convert all users to the bitmap interface.
Note the difference in behavior! We no longer mask the top 24 bits away
from x, hence we do not wrap tabs at 256th column. Instead, we silently
drop attempts to set a tab behind 256 columns. And we will also seek by
'\t' to the rightmost column, when behind that boundary. I do not think
the original behavior was desired and that someone relies on that. If
this turns out to be the case, we can change the added 'if's back to
masks here and there instead...
(Or we can increase the limit as fb consoles now have 240 chars here.
And they could have more with higher than my resolution, of course.)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Declare Gx_charset[2] instead of G0_charset and G1_charset. It makes
the code simpler (without ternary operators).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code for setting G0 and G1 is duplicated -- for each of them. Move
the code to a separate function (vc_setGx) and distinguish the two cases
by a parameter.
Change if-else-if to switch which allows for slightly better
optimization (decision tree).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code currently uses bitfields to store true-false values. Switch all
of that to bools. Apart from the cleanup, it saves 20B of code as many
shifts, ANDs, and ORs became simple movzb's.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce names (en enum) for 0, 1, and 2 constants. We now have
VCI_HALF_BRIGHT, VCI_NORMAL, and VCI_BOLD instead.
Apart from the cleanup,
1) the enum allows for better type checking, and
2) this saves some code. No more fiddling with bits is needed in
assembly now. (OTOH, the structure is larger.)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are two copies of some members of struct vc_data. This is because
we need to save them and restore later. Move these memebers to a
separate structure called vc_state. So now instead of members like:
vc_x, vc_y and vc_saved_x, vc_saved_y
we have
state and saved_state (of type: struct vc_state)
containing
state.x, state.y and saved_state.x, saved_state.y
This change:
* makes clear what is saved & restored
* eases save & restore by using memcpy (see save_cur and restore_cur)
Finally, we document the newly added struct vc_state using kernel-doc.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Because SCHED_FIFO is a broken scheduler model (see previous patches)
take away the priority field, the kernel can't possibly make an
informed decision.
Effectively no change.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.
This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.
There are a variety of indentation styles found.
a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'
In order to convert all of them to 1 tab + 'help', I ran the
following commend:
$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Now the last users of show_stack() got converted to use an explicit log
level, show_stack_loglvl() can drop it's redundant suffix and become once
again well known show_stack().
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Show the stack trace on a CPU with the same log level as "CPU%d" header.
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Link: http://lkml.kernel.org/r/20200418201944.482088-45-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Here is the tty and serial driver updates for 5.8-rc1
Nothing huge at all, just a lot of little serial driver fixes, updates
for new devices and features, and other small things. Full details are
in the shortlog.
Note, you will get a conflict merging with your tree in the
Documentation/devicetree/bindings/serial/rs485.yaml file, but it should
be pretty obvious what to do. If not, I'm sure Rob will clean it all up
afterwards :)
All of these have been in linux-next with no issues for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here is the tty and serial driver updates for 5.8-rc1
Nothing huge at all, just a lot of little serial driver fixes, updates
for new devices and features, and other small things. Full details are
in the shortlog.
All of these have been in linux-next with no issues for a while"
* tag 'tty-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (67 commits)
tty: serial: qcom_geni_serial: Add 51.2MHz frequency support
tty: serial: imx: clear Ageing Timer Interrupt in handler
serial: 8250_fintek: Add F81966 Support
sc16is7xx: Add flag to activate IrDA mode
dt-bindings: sc16is7xx: Add flag to activate IrDA mode
serial: 8250: Support rs485 bus termination GPIO
serial: 8520_port: Fix function param documentation
dt-bindings: serial: Add binding for rs485 bus termination GPIO
vt: keyboard: avoid signed integer overflow in k_ascii
serial: 8250: Enable 16550A variants by default on non-x86
tty: hvc_console, fix crashes on parallel open/close
serial: imx: Initialize lock for non-registered console
sc16is7xx: Read the LSR register for basic device presence check
sc16is7xx: Allow sharing the IRQ line
sc16is7xx: Use threaded IRQ
sc16is7xx: Always use falling edge IRQ
tty: n_gsm: Fix bogus i++ in gsm_data_kick
tty: n_gsm: Remove unnecessary test in gsm_print_packet()
serial: stm32: add no_console_suspend support
tty: serial: fsl_lpuart: Use __maybe_unused instead of #if CONFIG_PM_SLEEP
...
By far the biggest change in this cycle are the changes that allow much
earlier debug of systems that are hooked up via UART by taking advantage
of the earlycon framework to implement the kgdb I/O hooks before handing
over to the regular polling I/O drivers once they are available. When
discussing Doug's work we also found and fixed an broken
raw_smp_processor_id() sequence in in_dbg_master().
Also included are a collection of much smaller fixes and tweaks: a
couple of tweaks to ged rid of doc gen or coccicheck warnings, future
proof some internal calculations that made implicit power-of-2
assumptions and eliminate some rather weird handling of magic
environment variables in kdb.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
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Merge tag 'kgdb-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux
Pull kgdb updates from Daniel Thompson:
"By far the biggest change in this cycle are the changes that allow
much earlier debug of systems that are hooked up via UART by taking
advantage of the earlycon framework to implement the kgdb I/O hooks
before handing over to the regular polling I/O drivers once they are
available. When discussing Doug's work we also found and fixed an
broken raw_smp_processor_id() sequence in in_dbg_master().
Also included are a collection of much smaller fixes and tweaks: a
couple of tweaks to ged rid of doc gen or coccicheck warnings, future
proof some internal calculations that made implicit power-of-2
assumptions and eliminate some rather weird handling of magic
environment variables in kdb"
* tag 'kgdb-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
kdb: Remove the misfeature 'KDBFLAGS'
kdb: Cleanup math with KDB_CMD_HISTORY_COUNT
serial: amba-pl011: Support kgdboc_earlycon
serial: 8250_early: Support kgdboc_earlycon
serial: qcom_geni_serial: Support kgdboc_earlycon
serial: kgdboc: Allow earlycon initialization to be deferred
Documentation: kgdboc: Document new kgdboc_earlycon parameter
kgdb: Don't call the deinit under spinlock
kgdboc: Disable all the early code when kgdboc is a module
kgdboc: Add kgdboc_earlycon to support early kgdb using boot consoles
kgdboc: Remove useless #ifdef CONFIG_KGDB_SERIAL_CONSOLE in kgdboc
kgdb: Prevent infinite recursive entries to the debugger
kgdb: Delay "kgdbwait" to dbg_late_init() by default
kgdboc: Use a platform device to handle tty drivers showing up late
Revert "kgdboc: disable the console lock when in kgdb"
kgdb: Disable WARN_CONSOLE_UNLOCKED for all kgdb
kgdb: Return true in kgdb_nmi_poll_knock()
kgdb: Drop malformed kernel doc comment
kgdb: Fix spurious true from in_dbg_master()
Implement the read() function in the early console driver. With
recently added kgdboc_earlycon feature, this allows you to use kgdb
to debug fairly early into the system boot.
We only bother implementing this if polling is enabled since kgdb can't
be enabled without that.
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200507130644.v4.12.I8ee0811f0e0816dd8bfe7f2f5540b3dba074fae8@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Implement the read() function in the early console driver. With
recent kgdb patches this allows you to use kgdb to debug fairly early
into the system boot.
We only bother implementing this if polling is enabled since kgdb
can't be enabled without that.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20200507130644.v4.11.I8f668556c244776523320a95b09373a86eda11b7@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Implement the read() function in the early console driver. With
recent kgdb patches this allows you to use kgdb to debug fairly early
into the system boot.
We only bother implementing this if polling is enabled since kgdb
can't be enabled without that.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200507130644.v4.10.If2deff9679a62c1ce1b8f2558a8635dc837adf8c@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Currently there is no guarantee that an earlycon will be initialized
before kgdboc tries to adopt it. Almost the opposite: on systems
with ACPI then if earlycon has no arguments then it is guaranteed that
earlycon will not be initialized.
This patch mitigates the problem by giving kgdboc_earlycon a second
chance during console_init(). This isn't quite as good as stopping during
early parameter parsing but it is still early in the kernel boot.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20200430161741.1832050-1-daniel.thompson@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
When kgdboc is compiled as a module all of the "ekgdboc" and
"kgdb_earlycon" code isn't useful and, in fact, breaks compilation.
This is because early_param() isn't defined for modules and that's how
this code gets configured.
It turns out that this was broken by commit eae3e19ca9 ("kgdboc:
Remove useless #ifdef CONFIG_KGDB_SERIAL_CONSOLE in kgdboc") and then
made worse by commit 220995622d ("kgdboc: Add kgdboc_earlycon to
support early kgdb using boot consoles"). I guess the #ifdef wasn't
so useless, even if it wasn't obvious why it was useful. When kgdboc
was compiled as a module only "CONFIG_KGDB_SERIAL_CONSOLE_MODULE" was
defined, not "CONFIG_KGDB_SERIAL_CONSOLE". That meant that the old
module.
Let's basically do the same thing that the old code (pre-removal of
the #ifdef) did but use "IS_BUILTIN(CONFIG_KGDB_SERIAL_CONSOLE)" to
make it more obvious what the point of the check is. We'll fix
kgdboc_earlycon in a similar way.
Fixes: 220995622d ("kgdboc: Add kgdboc_earlycon to support early kgdb using boot consoles")
Fixes: eae3e19ca9 ("kgdboc: Remove useless #ifdef CONFIG_KGDB_SERIAL_CONSOLE in kgdboc")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200519084345.1.I91670accc8a5ddabab227eb63bb4ad3e2e9d2b58@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Pull uaccess/access_ok updates from Al Viro:
"Removals of trivially pointless access_ok() calls.
Note: the fiemap stuff was removed from the series, since they are
duplicates with part of ext4 series carried in Ted's tree"
* 'uaccess.access_ok' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vmci_host: get rid of pointless access_ok()
hfi1: get rid of pointless access_ok()
usb: get rid of pointless access_ok() calls
lpfc_debugfs: get rid of pointless access_ok()
efi_test: get rid of pointless access_ok()
drm_read(): get rid of pointless access_ok()
via-pmu: don't bother with access_ok()
drivers/crypto/ccp/sev-dev.c: get rid of pointless access_ok()
omapfb: get rid of pointless access_ok() calls
amifb: get rid of pointless access_ok() calls
drivers/fpga/dfl-afu-dma-region.c: get rid of pointless access_ok()
drivers/fpga/dfl-fme-pr.c: get rid of pointless access_ok()
cm4000_cs.c cmm_ioctl(): get rid of pointless access_ok()
nvram: drop useless access_ok()
n_hdlc_tty_read(): remove pointless access_ok()
tomoyo_write_control(): get rid of pointless access_ok()
btrfs_ioctl_send(): don't bother with access_ok()
fat_dir_ioctl(): hadn't needed that access_ok() for more than a decade...
dlmfs_file_write(): get rid of pointless access_ok()
only copy_to_user() is done to the address in question
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
To support BT use case over UART at baud rate of 3.2 Mbps,
we need SE clocks to run at 51.2MHz frequency. Previously this
frequency was not available in clk src, so, we were requesting
for 102.4 MHz and dividing it internally by 2 to get 51.2MHz.
As now 51.2MHz frequency is made available in clk src,
adding this frequency to UART frequency table.
We will save significant amount of power, if 51.2 is used
because it belongs to LowSVS range whereas 102.4 fall into
Nominal category.
Signed-off-by: satya priya <skakit@codeaurora.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/1590747282-5487-1-git-send-email-skakit@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The AGTIM flag must be cleared explicitly, otherwise the IRQ handler
will be called in an endless loop.
Fortunately, this issue currently doesn't affect mainline kernels in
practice, as the the RX FIFO trigger level is set to 1 in UFCR. When
setting the trigger level to a higher number, the issue is trivially
reproducible by any RX without DMA that doesn't fill the FIFO up to the
configured level.
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Link: https://lore.kernel.org/r/20200528154747.14201-1-matthias.schiffer@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fintek F81966 is a LPC/eSPI to 6 UARTs SuperIO. It has fully compatible
with F81866. It's also need check the IRQ mode with system assigned.
F81966 IRQ Mode setting:
0xf0
Bit1: IRQ_MODE0
Bit0: Share mode (always on)
0xf6
Bit3: IRQ_MODE1
Level/Low: IRQ_MODE0:0, IRQ_MODE1:0
Edge/High: IRQ_MODE0:1, IRQ_MODE1:0
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Cc: Ji-Ze Hong (Peter Hong) <peter_hong@fintek.com.tw>
Link: https://lore.kernel.org/r/20200528022429.32078-1-hpeter+linux_kernel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This series of uart controllers is able to work in IrDA mode.
Add per-port flag to the device-tree to enable that feature if needed.
Signed-off-by: Pascal Huerst <pascal.huerst@gmail.com>
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200529055058.1606910-3-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit e8759ad17d ("serial: uapi: Add support for bus termination")
introduced the ability to enable rs485 bus termination from user space.
So far the feature is only used by a single driver, 8250_exar.c, using a
hardcoded GPIO pin specific to Siemens IOT2040 products.
Provide for a more generic solution by allowing specification of an
rs485 bus termination GPIO pin in the device tree: Amend the serial
core to retrieve the GPIO from the device tree (or ACPI table) and amend
the default ->rs485_config() callback for 8250 drivers to change the
GPIO on request from user space.
Perhaps 8250_exar.c can be converted to the generic approach in a
follow-up patch.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Link: https://lore.kernel.org/r/94c6c800d1ca9fa04766dd1d43a8272c5ad4bedd.1589811297.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The parameter is named p while the documentation talks about up.
Fix the doc to be in line with the code.
Fixes: 058bc104f7 ("serial: 8250: Generalize rs485 software emulation")
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200517215610.2131618-2-heiko@sntech.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When k_ascii is invoked several times in a row there is a potential for
signed integer overflow:
UBSAN: Undefined behaviour in drivers/tty/vt/keyboard.c:888:19 signed integer overflow:
10 * 1111111111 cannot be represented in type 'int'
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.11 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xce/0x128 lib/dump_stack.c:118
ubsan_epilogue+0xe/0x30 lib/ubsan.c:154
handle_overflow+0xdc/0xf0 lib/ubsan.c:184
__ubsan_handle_mul_overflow+0x2a/0x40 lib/ubsan.c:205
k_ascii+0xbf/0xd0 drivers/tty/vt/keyboard.c:888
kbd_keycode drivers/tty/vt/keyboard.c:1477 [inline]
kbd_event+0x888/0x3be0 drivers/tty/vt/keyboard.c:1495
While it can be worked around by using check_mul_overflow()/
check_add_overflow(), it is better to introduce a separate flag to
signal that number pad is being used to compose a symbol, and
change type of the accumulator from signed to unsigned, thus
avoiding undefined behavior when it overflows.
Reported-by: Kyungtae Kim <kt0755@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200525232740.GA262061@dtor-ws
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some embedded devices still use these serial ports; make sure they're
still enabled by default on architectures more likely to have them, to
avoid rendering someone's console unavailable.
Reported-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reported-by: Maxim Kochetkov <fido_max@inbox.ru>
Fixes: dc56ecb81a ("serial: 8250: Support disabling mdelay-filled probes of 16550A variants")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Link: https://lore.kernel.org/r/a20b5fb7dd295cfb48160eecf4bdebd76332d67d.1590509426.git.josh@joshtriplett.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hvc_open sets tty->driver_data to NULL when open fails at some point.
Typically, the failure happens in hp->ops->notifier_add(). If there is
a racing process which tries to open such mangled tty, which was not
closed yet, the process will crash in hvc_open as tty->driver_data is
NULL.
All this happens because close wants to know whether open failed or not.
But ->open should not NULL this and other tty fields for ->close to be
happy. ->open should call tty_port_set_initialized(true) and close
should check by tty_port_initialized() instead. So do this properly in
this driver.
So this patch removes these from ->open:
* tty_port_tty_set(&hp->port, NULL). This happens on last close.
* tty->driver_data = NULL. Dtto.
* tty_port_put(&hp->port). This happens in shutdown and until now, this
must have been causing a reference underflow, if I am not missing
something.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: stable <stable@vger.kernel.org>
Reported-and-tested-by: Raghavendra <rananta@codeaurora.org>
Link: https://lore.kernel.org/r/20200526145632.13879-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit a3cb39d258
("serial: core: Allow detach and attach serial device for console")
changed a bit logic behind lock initialization since for most of the console
driver it's supposed to have lock already initialized even if console is not
enabled. However, it's not the case for Freescale IMX console.
Initialize lock explicitly in the ->probe().
Note, there is still an open question should or shouldn't not this driver
register console properly.
Fixes: a3cb39d258 ("serial: core: Allow detach and attach serial device for console")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200525105952.13744-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the driver probes just fine and binds all its resources even
if the physical device is not present.
As the device lacks an identification register, let's at least read the
LSR register to check whether a device at the configured address responds
to the request at all.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-7-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the interrupt line is shared with other devices, the IRQ must be
level-triggered, as only one device can trigger a falling edge. To support
this, try to acquire the IRQ with IRQF_TRIGGER_LOW|IRQF_SHARED first.
Interrupt controllers that lack support for level-triggers will return an
error, in which case the driver will now retry the acqusition with
IRQF_TRIGGER_FALLING, which was also the default before.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-6-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use a threaded IRQ handler to get rid of the irq_work kthread.
This also allows for the driver to use interrupts generated by
a threaded controller.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-5-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver currently only uses IRQF_TRIGGER_FALLING if the probing
happened without a device-tree setup. The device however will always
generate falling edges on its IRQ line, so let's use that flag in
all cases.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-4-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When submitting the previous fix "tty: n_gsm: Fix waking up upper tty
layer when room available". It was suggested to switch from a while to
a for loop, but when doing it, there was a remaining bogus i++.
This patch removes this i++ and also reorganizes the code making it more
compact.
Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Link: https://lore.kernel.org/r/20200518084517.2173242-3-gregory.clement@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the length is zero then the print_hex_dump_bytes won't output
anything, so testing the length before the call is unnecessary.
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Link: https://lore.kernel.org/r/20200518084517.2173242-2-gregory.clement@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In order to display console messages in low power mode, console pins
must be kept active after suspend call.
Initial patch "serial: stm32: add support for no_console_suspend" was part
of "STM32 usart power improvement" series, but as dependancy to
console_suspend pinctl state has been removed to fit with Rob comment [1],
this patch has no more dependancy with any other patch of this series.
[1] https://lkml.org/lkml/2019/7/9/451
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>
Link: https://lore.kernel.org/r/20200519094104.27082-1-erwan.leray@st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We want to enable kgdb to debug the early parts of the kernel.
Unfortunately kgdb normally is a client of the tty API in the kernel
and serial drivers don't register to the tty layer until fairly late
in the boot process.
Serial drivers do, however, commonly register a boot console. Let's
enable the kgdboc driver to work with boot consoles to provide early
debugging.
This change co-opts the existing read() function pointer that's part
of "struct console". It's assumed that if a boot console (with the
flag CON_BOOT) has implemented read() that both the read() and write()
function are polling functions. That means they work without
interrupts and read() will return immediately (with 0 bytes read) if
there's nothing to read. This should be a safe assumption since it
appears that no current boot consoles implement read() right now and
there seems no reason to do so unless they wanted to support
"kgdboc_earlycon".
The normal/expected way to make all this work is to use
"kgdboc_earlycon" and "kgdboc" together. You should point them both
to the same physical serial connection. At boot time, as the system
transitions from the boot console to the normal console (and registers
a tty), kgdb will switch over.
One awkward part of all this, though, is that there can be a window
where the boot console goes away and we can't quite transtion over to
the main kgdboc that uses the tty layer. There are two main problems:
1. The act of registering the tty doesn't cause any call into kgdboc
so there is a window of time when the tty is there but kgdboc's
init code hasn't been called so we can't transition to it.
2. On some serial drivers the normal console inits (and replaces the
boot console) quite early in the system. Presumably these drivers
were coded up before earlycon worked as well as it does today and
probably they don't need to do this anymore, but it causes us
problems nontheless.
Problem #1 is not too big of a deal somewhat due to the luck of probe
ordering. kgdboc is last in the tty/serial/Makefile so its probe gets
right after all other tty devices. It's not fun to rely on this, but
it does work for the most part.
Problem #2 is a big deal, but only for some serial drivers. Other
serial drivers end up registering the console (which gets rid of the
boot console) and tty at nearly the same time.
The way we'll deal with the window when the system has stopped using
the boot console and the time when we're setup using the tty is to
keep using the boot console. This may sound surprising, but it has
been found to work well in practice. If it doesn't work, it shouldn't
be too hard for a given serial driver to make it keep working.
Specifically, it's expected that the read()/write() function provided
in the boot console should be the same (or nearly the same) as the
normal kgdb polling functions. That means continuing to use them
should work just fine. To make things even more likely to work work
we'll also trap the recently added exit() function in the boot console
we're using and delay any calls to it until we're all done with the
boot console.
NOTE: there could be ways to use all this in weird / unexpected ways.
If you do something like this, it's a bit of a buyer beware situation.
Specifically:
- If you specify only "kgdboc_earlycon" but not "kgdboc" then
(depending on your serial driver) things will probably work OK, but
you'll get a warning printed the first time you use kgdb after the
boot console is gone. You'd only be able to do this, of course, if
the serial driver you're running atop provided an early boot console.
- If your "kgdboc_earlycon" and "kgdboc" devices are not the same
device things should work OK, but it'll be your job to switch over
which device you're monitoring (including figuring out how to switch
over gdb in-flight if you're using it).
When trying to enable "kgdboc_earlycon" it should be noted that the
names that are registered through the boot console layer and the tty
layer are not the same for the same port. For example when debugging
on one board I'd need to pass "kgdboc_earlycon=qcom_geni
kgdboc=ttyMSM0" to enable things properly. Since digging up the boot
console name is a pain and there will rarely be more than one boot
console enabled, you can provide the "kgdboc_earlycon" parameter
without specifying the name of the boot console. In this case we'll
just pick the first boot that implements read() that we find.
This new "kgdboc_earlycon" parameter should be contrasted to the
existing "ekgdboc" parameter. While both provide a way to debug very
early, the usage and mechanisms are quite different. Specifically
"kgdboc_earlycon" is meant to be used in tandem with "kgdboc" and
there is a transition from one to the other. The "ekgdboc" parameter,
on the other hand, replaces the "kgdboc" parameter. It runs the same
logic as the "kgdboc" parameter but just relies on your TTY driver
being present super early. The only known usage of the old "ekgdboc"
parameter is documented as "ekgdboc=kbd earlyprintk=vga". It should
be noted that "kbd" has special treatment allowing it to init early as
a tty device.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/20200507130644.v4.8.I8fba5961bf452ab92350654aa61957f23ecf0100@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
This file is only ever compiled if that config is on since the
Makefile says:
obj-$(CONFIG_KGDB_SERIAL_CONSOLE) += kgdboc.o
Let's get rid of the useless #ifdef.
Reported-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200507130644.v4.7.Icb528f03d0026d957e60f537aa711ada6fd219dc@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Andy Shevchenko