The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().
Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231110152927.70601-44-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a serial port is used for kernel console output, then all
modifications to the UART registers which are done from other contexts,
e.g. getty, termios, are interference points for the kernel console.
So far this has been ignored and the printk output is based on the
principle of hope. The rework of the console infrastructure which aims to
support threaded and atomic consoles, requires to mark sections which
modify the UART registers as unsafe. This allows the atomic write function
to make informed decisions and eventually to restore operational state. It
also allows to prevent the regular UART code from modifying UART registers
while printk output is in progress.
All modifications of UART registers are guarded by the UART port lock,
which provides an obvious synchronization point with the console
infrastructure.
To avoid adding this functionality to all UART drivers, wrap the
spin_[un]lock*() invocations for uart_port::lock into helper functions
which just contain the spin_[un]lock*() invocations for now. In a
subsequent step these helpers will gain the console synchronization
mechanisms.
Converted with coccinelle. No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20230914183831.587273-66-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # for imx
Link: https://lore.kernel.org/r/20230724205440.767071-1-robh@kernel.org
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 Sparc HV 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: Anatoly Pugachev <matorola@gmail.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Anatoly Pugachev <matorola@gmail.com>
Link: https://lore.kernel.org/r/20200402172026.79478-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The SUPPORT_SYSRQ ifdeffery is not nice as:
- May create misunderstanding about sizeof(struct uart_port) between
different objects
- Prevents moving functions from serial_core.h
- Reduces readability (well, it's ifdeffery - it's hard to follow)
In order to remove SUPPORT_SYSRQ, has_sysrq variable has been added.
Initialise it in driver's probe and remove ifdeffery.
Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20191213000657.931618-46-dima@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In d5a2aa24, the name in struct console sunhv_console was changed from "ttyS"
to "ttyHV" while the name in struct uart_ops sunhv_pops remained unchanged.
This results in the hypervisor console device to be listed as "ttyHV0" under
/proc/consoles while the device node is still named "ttyS0":
root@osaka:~# cat /proc/consoles
ttyHV0 -W- (EC p ) 4:64
tty0 -WU (E ) 4:1
root@osaka:~# readlink /sys/dev/char/4:64
../../devices/root/f02836f0/f0285690/tty/ttyS0
root@osaka:~#
This means that any userland code which tries to determine the name of the
device file of the hypervisor console device can not rely on the information
provided by /proc/consoles. In particular, booting current versions of debian-
installer inside a SPARC LDOM will fail with the installer unable to determine
the console device.
After renaming the device in struct uart_ops sunhv_pops to "ttyHV" as well,
the inconsistency is fixed and it is possible again to determine the name
of the device file of the hypervisor console device by reading the contents
of /proc/console:
root@osaka:~# cat /proc/consoles
ttyHV0 -W- (EC p ) 4:64
tty0 -WU (E ) 4:1
root@osaka:~# readlink /sys/dev/char/4:64
../../devices/root/f02836f0/f0285690/tty/ttyHV0
root@osaka:~#
With this change, debian-installer works correctly when installing inside
a SPARC LDOM.
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now we can also jump to boot prom from sunhv console by sending
break twice on console for both running and panicked kernel
cases.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On panic, all other CPUs are stopped except the one which had
hit panic. To keep console alive, we need to migrate hvcons irq
to panicked CPU.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In each call to hv_remove(), con_read_page and con_write_page is not
getting freed and lead to memory leakage. Fix this by freeing both
pointers in hv_remove().
Signed-off-by: Souptick joarder <jrdr.linux@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We accidentally take the "port->lock" twice in a row. This old code
was supposed to be deleted.
Fixes: e58e241c17 ('sparc: serial: Clean up the locking for -rt')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When sysrq is triggered from console, serial driver for SUN hypervisor
console receives a console break and enables the sysrq. It expects a valid
sysrq char following with break. Meanwhile if driver receives 'NULL'
ASCII char then it disables sysrq and sysrq handler will never be invoked.
This fix skips calling uart sysrq handler when 'NULL' is received while
sysrq is enabled.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Acked-by: Karl Volz <karl.volz@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Constifies sunhv_ops structures in tty's serial
driver since they are not modified after their
initialization.
Detected and found using Coccinelle.
Suggested-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Aya Mahfouz <mahfouz.saif.elyazal@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Kconfig for this driver is currently:
config SERIAL_SUNHV
bool "Sun4v Hypervisor Console support"
...meaning that it currently is not being built as a module by
anyone. Lets remove the modular and unused code here, so that
when reading the driver there is no doubt it is builtin-only.
Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.
We don't swap module.h for init.h since this file has init.h already.
We leave some tags like MODULE_LICENSE for documentation purposes, and
for the "git blame" value. Also note that MODULE_DEVICE_TABLE is a
no-op for non-modular code, so we remove that too.
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: sparclinux@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
START_CHAR() & STOP_CHAR() can be disabled if set to '\0'
(__DISABLED_CHAR). UART drivers which define a send_xchar()
handler must not transmit __DISABLED_CHAR.
Document requirement.
Affected drivers:
sunsab
sunhv
cc: David S. Miller <davem@davemloft.net>
cc: <sparclinux@vger.kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the wrapper functions for getting and setting the driver data using
platform_device instead of using dev_{get,set}_drvdata() with &pdev->dev,
so we can directly pass a struct platform_device.
Also, unnecessary dev_set_drvdata() is removed, because the driver core
clears the driver data to NULL after device_release or on probe failure.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.
Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.
IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.
Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.
tty_insert_flip_string this time.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.
tty_insert_flip_char is the next one to proceed. This one is used all
over the code, so the patch is huge.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are multiple users of this file from different source
paths now, and rather than have ../ paths in include statements,
just move the file to the linux header dir.
Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Get rid of users of of_platform_driver in drivers/serial. The
of_platform_{,un}register_driver functions are going away, so the
users need to be converted to using the platform_bus_type directly.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
The serial drivers are really just tty drivers, so move them to
drivers/tty/ to make things a bit neater overall.
This is part of the tty/serial driver movement proceedure as proposed by
Arnd Bergmann and approved by everyone involved a number of months ago.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl>
Cc: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
