There is a warning reported by coccinelle:
./drivers/tty/serial/8250/8250_men_mcb.c:226:6-19: WARNING:
Unsigned expression compared with zero: data -> line [ i ] < 0
The array "line" of serial_8250_men_mcb_data is used to record the
registered serial port. When register a port failed, it will return
an error code, but the type of "line" is "unsigned int", causing
the error code to reverse. Modify the type of "data -> line" to solve
this problem.
Fixes: 2554e6ba28 ("8250_men_mcb: Read num ports from register data.")
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230803142053.1308926-1-lizetao1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At least freeze, restore and thaw need to be set in order for the driver
to support system hibernation. The existing suspend/resume functions can
be reused since those functions don't touch the device's power state or
wakeup capability. Use the helper macros SET_SYSTEM_SLEEP_PM_OPS and
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS for symmetry with similar drivers.
Signed-off-by: Anton Eliasson <anton.eliasson@axis.com>
Link: https://lore.kernel.org/r/20230803-samsung_tty_pm_ops-v1-1-1ea7be72194d@axis.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As &info->lock is acquired by slgt_interrupt() under irq context, other
process context code acquiring the lock should disable irq, otherwise
deadlock could happen if the irq preempt the execution while the
lock is held in process context on the same CPU.
Lock acquisition inside set_params32() does not disable irq, and this
function is called by slgt_compat_ioctl() from process context.
Possible deadlock scenario:
slgt_compat_ioctl()
-> set_params32()
-> spin_lock(&info->lock)
<irq>
-> slgt_interrupt()
-> spin_lock(&info->lock); (deadlock here)
This flaw was found by an experimental static analysis tool I am developing
for irq-related deadlock. x86_64 allmodconfig using gcc shows no new
warning.
The patch fixes the potential deadlock by spin_lock_irqsave() like other
lock acquisition sites.
Signed-off-by: Chengfeng Ye <dg573847474@gmail.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230728123901.64225-1-dg573847474@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a warning reported by coccinelle:
./drivers/tty/serial/ma35d1_serial.c:791:3-8:
No need to set .owner here. The core will do it.
The module_platform_driver() will set "THIS_MODULE" to driver.owner
when register a driver for platform-level devices, so it is redundant
initialization to set driver.owner in ma35d1serial_driver statement.
Remove it to silence the warning.
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Link: https://lore.kernel.org/r/20230803032353.3045221-1-lizetao1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We are missing the serial core controller id for the serial core port
name. Let's fix the issue for sane sysfs output, and to avoid issues
addressing serial ports later on.
And as we're now showing the controller id, the "ctrl" and "port" prefix
for the DEVNAME become useless, we can just drop them. Let's standardize on
DEVNAME:0 for controller name, where 0 is the controller id. And
DEVNAME:0.0 for port name, where 0.0 are the controller id and port id.
This makes the sysfs output nicer, on qemu for example:
$ ls /sys/bus/serial-base/devices
00:04:0 serial8250:0 serial8250:0.2
00:04:0.0 serial8250:0.1 serial8250:0.3
Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230725054216.45696-4-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The serial core port id should be serial core controller specific port
instance, which is not always the port->line index.
For example, 8250 driver maps a number of legacy ports, and when a
hardware specific device driver takes over, we typically have one
driver instance for each port. Let's instead add port->port_id to
keep track serial ports mapped to each serial core controller instance.
Currently this is only a cosmetic issue for the serial core port device
names. The issue can be noticed looking at /sys/bus/serial-base/devices
for example though. Let's fix the issue to avoid port addressing issues
later on.
Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230725054216.45696-3-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Do not read the data register to clear the error flags for lpuart32
platforms, the additional read may cause the receive FIFO underflow
since the DMA has already read the data register.
Actually all lpuart32 platforms support write 1 to clear those error
bits, let's use this method to better clear the error flags.
Fixes: 42b68768e5 ("serial: fsl_lpuart: DMA support for 32-bit variant")
Cc: stable <stable@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20230801022304.24251-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After walking and trying to clean up the worst in the driver, I came
across the pci_driver::remove() _empty_ implementation. That would crash
the system at least during hot-unplug (or write to remove in sysfs).
There are many other problems:
* Initialization + deinitialization apparently comes from no-hotplug
support age. It needs a rewrite.
* Hairy debug macros. Drop them.
* Use of self-baked lists. Replace by list.
* The order of the functions should be inverted and fwd decls dropped.
* Coding style from the stone age. Fix.
* I assume there are many bugs, but the code is unreadable at times, so
hard to judge. There is one example posted [1].
I was able to find only one user back in 2016. So mark the driver as
BROKEN for some time. Either someone will notice and we can bring the
driver to this century. Or we will drop it completely if noone cares.
[1] https://lore.kernel.org/all/20230728123901.64225-1-dg573847474@gmail.com/
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Chengfeng Ye <dg573847474@gmail.com>
Link: https://lore.kernel.org/r/20230731090002.15680-8-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It makes the code more readable and less error-prone as the result is
returned and not stored in a variable newly defined inside the macro.
Note that cast to 'unsigned long' and back to 'void *' was eliminated as
info->reg_addr is 'char *' already (so the addition is per bytes
already).
This nicely cleans up the callers too.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230731090002.15680-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull tty/serial fixes from Greg KH:
"Here are some small TTY and serial driver fixes for 6.5-rc4 for some
reported problems. Included in here is:
- TIOCSTI fix for braille readers
- documentation fix for minor numbers
- MAINTAINERS update for new serial files in -rc1
- minor serial driver fixes for reported problems
All of these have been in linux-next with no reported problems"
* tag 'tty-6.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: 8250_dw: Preserve original value of DLF register
tty: serial: sh-sci: Fix sleeping in atomic context
serial: sifive: Fix sifive_serial_console_setup() section
Documentation: devices.txt: reconcile serial/ucc_uart minor numers
MAINTAINERS: Update TTY layer for lists and recently added files
tty: n_gsm: fix UAF in gsm_cleanup_mux
TIOCSTI: always enable for CAP_SYS_ADMIN
The global pointer 'sprd_port' may not zero when sprd_probe returns
failure, that is a risk for sprd_port to be accessed afterward, and
may lead to unexpected errors.
For example:
There are two UART ports, UART1 is used for console and configured in
kernel command line, i.e. "console=";
The UART1 probe failed and the memory allocated to sprd_port[1] was
released, but sprd_port[1] was not set to NULL;
In UART2 probe, the same virtual address was allocated to sprd_port[2],
and UART2 probe process finally will go into sprd_console_setup() to
register UART1 as console since it is configured as preferred console
(filled to console_cmdline[]), but the console parameters (sprd_port[1])
belong to UART2.
So move the sprd_port[] assignment to where the port already initialized
can avoid the above issue.
Fixes: b7396a38fb ("tty/serial: Add Spreadtrum sc9836-uart driver support")
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20230725064053.235448-1-chunyan.zhang@unisoc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
According to the IOControl register bits description in the page 31 of
the product datasheet, we know the bit 3 of IOControl register is
softreset, this bit will self-clearing once the reset finish.
In the probe, the softreset bit is set, and when we read this register
from debugfs/regmap interface, we found the softreset bit is still
setting, this confused us for a while. Finally we found this register
is cached, to read the real value from register, we could put it
into the regmap_volatile().
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Link: https://lore.kernel.org/r/20230724034727.17335-1-hui.wang@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Macroses for name generation are not useful. They hide the real place
for object declaration. Instead, use direct names such as
'meson_uart_driver_*' and 'meson_serial_console_*' for all objects.
Additionally, rename 'MESON_SERIAL_CONSOLE_DEFINE()' to
'MESON_SERIAL_CONSOLE()', and 'MESON_UART_DRIVER_DEFINE()' to
'MESON_UART_DRIVER()' to simplify the code.
Signed-off-by: Dmitry Rokosov <ddrokosov@sberdevices.ru>
Suggested-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20230728071522.17503-1-ddrokosov@sberdevices.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>