With this, processes without CAP_SYS_ADMIN are able to use TIOCLINUX with
subcode TIOCL_SETSEL, in the selection modes TIOCL_SETPOINTER,
TIOCL_SELCLEAR and TIOCL_SELMOUSEREPORT.
TIOCL_SETSEL was previously changed to require CAP_SYS_ADMIN, as this IOCTL
let callers change the selection buffer and could be used to simulate
keypresses. These three TIOCL_SETSEL selection modes, however, are safe to
use, as they do not modify the selection buffer.
This fixes a mouse support regression that affected Emacs (invisible mouse
cursor).
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/ee3ec63269b43b34e1c90dd8c9743bf8@finder.org
Fixes: 8d1b43f6a6df ("tty: Restrict access to TIOCLINUX' copy-and-paste subcommands")
Signed-off-by: Günther Noack <gnoack@google.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Link: https://lore.kernel.org/r/20250110142122.1013222-1-gnoack@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
lockdep detects the following circular locking dependency:
CPU 0 CPU 1
========================== ============================
cdns_uart_isr() printk()
uart_port_lock(port) console_lock()
cdns_uart_console_write()
if (!port->sysrq)
uart_port_lock(port)
uart_handle_break()
port->sysrq = ...
uart_handle_sysrq_char()
printk()
console_lock()
The fixed commit attempts to avoid this situation by only taking the
port lock in cdns_uart_console_write if port->sysrq unset. However, if
(as shown above) cdns_uart_console_write runs before port->sysrq is set,
then it will try to take the port lock anyway. This may result in a
deadlock.
Fix this by splitting sysrq handling into two parts. We use the prepare
helper under the port lock and defer handling until we release the lock.
Fixes: 74ea66d4ca06 ("tty: xuartps: Improve sysrq handling")
Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
Cc: stable@vger.kernel.org # c980248179d: serial: xilinx_uartps: Use port lock wrappers
Acked-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20250110213822.2107462-1-sean.anderson@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need the debugfs / driver-core fixes in here as well for testing and
to build on top of.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since task->comm is guaranteed to be NUL-terminated, we can print it
directly without the need to copy it into a separate buffer. This
simplifies the code and avoids unnecessary operations.
Link: https://lkml.kernel.org/r/20241219023452.69907-6-laoar.shao@gmail.com
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org> (For tty)
Reviewed-by: Lyude Paul <lyude@redhat.com> (For nouveau)
Cc: Oded Gabbay <ogabbay@kernel.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tursulin@ursulin.net>
Cc: David Airlie <airlied@gmail.com>
Cc: Simona Vetter <simona@ffwll.ch>
Cc: Karol Herbst <kherbst@redhat.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Danilo Krummrich <dakr@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: "André Almeida" <andrealmeid@igalia.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Kalle Valo <kvalo@kernel.org>
Cc: Kees Cook <kees@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineet Gupta <vgupta@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The 8250 driver no longer depends on @oops_in_progress and
will no longer violate the port->lock locking constraints.
This reverts commit 3d9e6f556e235ddcdc9f73600fdd46fe1736b090.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250107212702.169493-7-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement the necessary callbacks to switch the 8250 console driver
to perform as an nbcon console.
Add implementations for the nbcon console callbacks:
->write_atomic()
->write_thread()
->device_lock()
->device_unlock()
and add CON_NBCON to the initial @flags.
All register access in the callbacks are within unsafe sections.
The ->write_atomic() and ->write_thread() callbacks allow safe
handover/takeover per byte and add a preceding newline if they
take over from another context mid-line.
For the ->write_atomic() callback, a new irq_work is used to defer
modem control since it may be called from a context that does not
allow waking up tasks.
Note: A new __serial8250_clear_IER() is introduced for direct
clearing of UART_IER. This will allow to restore the lockdep
check to serial8250_clear_IER() in a follow-up commit.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250107212702.169493-6-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For RS485 mode, if SER_RS485_RX_DURING_TX is not available, the
console ->write() callback needs to enable/disable Tx. It does
this by calling the ->rs485_start_tx() and ->rs485_stop_tx()
callbacks. However, some of these callbacks also disable/enable
interrupts and makes power management calls. This causes 2
problems for console writing:
1. A console write can occur in contexts that are illegal for
pm_runtime_*(). It is not even necessary for console writing
to use pm_runtime_*() because a console already does this in
serial8250_console_setup() and serial8250_console_exit().
2. The console ->write() callback already handles
disabling/enabling the interrupts by properly restoring the
previous IER value.
Add an argument @toggle_ier to the ->rs485_start_tx() and
->rs485_stop_tx() callbacks to specify if they may disable/enable
receive interrupts while using pm_runtime_*(). Console writing
will not allow the toggling.
For all call sites other than console writing there is no
functional change.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250107212702.169493-5-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently serial8250_console_fifo_write() directly writes into
the UART_TX register rather than using the high-level function
serial8250_console_putchar(). This is because
serial8250_console_putchar() waits for the holding register to
become empty, which would defeat the purpose of the FIFO code.
Move the LSR_THRE waiting to a new function
serial8250_console_wait_putchar() so that the FIFO code can use
serial8250_console_putchar(). This will be particularly important
for a follow-up commit, where output bytes are inspected to track
newlines.
This is only refactoring and has no functional change.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250107212702.169493-4-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rather than using a hard-coded per-character Tx-timeout of 10ms,
use the frame time to determine a timeout value. The value is
doubled to ensure that a timeout is only hit during unexpected
circumstances.
Since the frame time may not be available during early printing,
the previous 10ms value is kept as a fallback.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250107212702.169493-3-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After a console has written a record into UART_TX, it uses
wait_for_xmitr() to wait until the data has been sent out before
returning. However, wait_for_xmitr() will timeout after 10ms,
regardless if the data has been transmitted or not.
For single bytes, this timeout is sufficient even at very slow
baud rates, such as 1200bps. However, when FIFO mode is used,
there may be 64 bytes pushed into the FIFO at once. At a baud
rate of 115200bps, the 10ms timeout is still sufficient. But
when using lower baud rates (such as 57600bps), the timeout
is _not_ sufficient. This causes longer lines to be cut off,
resulting in lost and horribly misformatted output on the
console.
When using FIFO mode, take the number of bytes into account to
determine an appropriate maximum timeout. Increasing the timeout
does not affect performance since ideally the timeout never
occurs.
Fixes: 8f3631f0f6eb ("serial/8250: Use fifo in 8250 console driver")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Wander Lairson Costa <wander@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250107212702.169493-2-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The use of of_property_read_bool() for non-boolean properties is
deprecated in favor of of_property_present() when testing for property
presence.
As of_property_present() returns a boolean, use that directly
and simplify the code a bit while we're here.
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Acked-by: Richard Genoud <richard.genoud@bootlin.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20250109182053.3970547-1-robh@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fall back to polling mode if no interrupt is configured because there
is no possibility to connect the interrupt pin.
If "interrupts" property is missing in devicetree the driver
uses a delayed worker to pull the state of interrupt status registers.
Signed-off-by: Andre Werner <andre.werner@systec-electronic.com>
Link: https://lore.kernel.org/r/20250110073104.1029633-2-andre.werner@systec-electronic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
LAN969x uses the Atmel serial, so make it selectable for ARCH_LAN969X.
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20250108131045.40642-3-robert.marko@sartura.hr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The LKP robot complains about:
drivers/tty/mips_ejtag_fdc.c:1224:31: error: incompatible pointer types passing 'const char *[1]' to parameter of type 'const u8 **' (aka 'const unsigned char **')
Fix this by turning the missing pieces (fetch from kgdbfdc_wbuf) to u8
too. Note the filling part (kgdbfdc_write_char()) already receives and
stores u8 to kgdbfdc_wbuf.
Fixes: ce7cbd9a6c81 ("tty: mips_ejtag_fdc: use u8 for character pointers")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202501101327.oGdWbmuk-lkp@intel.com/
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250110115228.603980-1-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, code retries n2 times to open control dlci in ABM mode before
switching to ADM mode, but only if DM has been received. This contradicts
to the comment that dlci is switched to control mode unconditionally if
DLCI_OPENING retries time out. Also, it does not make sense to continue
trying once DM has received.
Change the logic to switch to ADM mode upon DM received. That way control
channel state will change to DLCI_OPEN way faster. Fix the misleading
comment while at it.
Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20241228150100.100354-3-ivo.g.dimitrov.75@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently code does not wait for channel 0 open sequence to complete before
pushing data to the other channels. Also, if userland opens tty, it will
receive EL2NSYNC. Both issues result in hard to predict initialization
sequence and possible userland failures.
Fix that by waiting channel 0 open sequence to complete before attempting
opening of the other channels. Also, if tty open() is attempted while
channel 0 is opening, wait until sequence is complete before returning to
userland.
Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20241228150100.100354-2-ivo.g.dimitrov.75@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Need to flush UART RX and TX FIFO when lpuart is shutting down to make
sure restore a clean data transfer environment.
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20250107074834.3115230-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some SoCs like the i.MX943 have aliases for up to 12 UARTs, need to
increase UART_NR from 8 to 12 to support lpuart9-12 to avoid
initialization failures.
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20250103071154.3070924-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Constify the following API:
struct device *device_find_child(struct device *dev, void *data,
int (*match)(struct device *dev, void *data));
To :
struct device *device_find_child(struct device *dev, const void *data,
device_match_t match);
typedef int (*device_match_t)(struct device *dev, const void *data);
with the following reasons:
- Protect caller's match data @*data which is for comparison and lookup
and the API does not actually need to modify @*data.
- Make the API's parameters (@match)() and @data have the same type as
all of other device finding APIs (bus|class|driver)_find_device().
- All kinds of existing device match functions can be directly taken
as the API's argument, they were exported by driver core.
Constify the API and adapt for various existing usages.
BTW, various subsystem changes are squashed into this commit to meet
'git bisect' requirement, and this commit has the minimal and simplest
changes to complement squashing shortcoming, and that may bring extra
code improvement.
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Uwe Kleine-König <ukleinek@kernel.org> # for drivers/pwm
Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20241224-const_dfc_done-v5-4-6623037414d4@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Data loss on serial line was observed during communication through
serial ports ttyAMA1 and ttyAMA2 interconnected via RS485 transcievers.
Both ports are in one BCM2711 (Compute Module CM40) and they share
the same interrupt line.
The problem is caused by long waiting for tx queue flush in the function
pl011_rs485_tx_stop. Udelay or mdelay are used to wait.
The function is called from the interrupt handler. If multiple devices
share a single interrupt line, late processing of pending interrupts
and data loss may occur. When operation of both devices are synchronous,
collisions are quite often.
This rework is based on the method used in tty/serial/imx.c
Use hrtimer instead of udelay and mdelay calls.
Replace simple bool variable rs485_tx_started by 4-state variable
rs485_tx_state.
Tested-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Signed-off-by: Miroslav Ondra <ondra@faster.cz>
Link: https://lore.kernel.org/r/20241221-amba-rts-v3-1-d3d444681419@faster.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 30e945861f3b ("serial: stm32: add support for break control")
added another usage of the port lock, but was merged on the same day as
c5d06662551c ("serial: stm32: Use port lock wrappers"), therefore the
latter did not update this usage to use the port lock wrappers.
Fixes: c5d06662551c ("serial: stm32: Use port lock wrappers")
Cc: stable <stable@kernel.org>
Signed-off-by: Ben Wolsieffer <ben.wolsieffer@hefring.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20241216145323.111612-1-ben.wolsieffer@hefring.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When executing 'echo mem > /sys/power/state', the following
deadlock occurs. Since there is output during the serial
port entering the suspend process, the suspend will be
interrupted, resulting in the nesting of locks. Therefore,
use uart_port_lock_irq() instead of uart_port_unlock().
WARNING: inconsistent lock state
6.12.0-rc2-00002-g3c199ed5bd64-dirty #23 Not tainted
--------------------------------
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
sh/494 [HC0[0]:SC0[0]:HE1:SE1] takes:
c4db5850 (&port_lock_key){?.-.}-{3:3}, at: imx_uart_enable_wakeup+0x14/0x254
{IN-HARDIRQ-W} state was registered at:
lock_acquire+0x104/0x348
_raw_spin_lock+0x48/0x84
imx_uart_int+0x14/0x4dc
__handle_irq_event_percpu+0xac/0x2fc
handle_irq_event_percpu+0xc/0x40
handle_irq_event+0x38/0x8c
handle_fasteoi_irq+0xb4/0x1b8
handle_irq_desc+0x1c/0x2c
gic_handle_irq+0x6c/0xa0
generic_handle_arch_irq+0x2c/0x64
call_with_stack+0x18/0x20
__irq_svc+0x9c/0xbc
_raw_spin_unlock_irqrestore+0x2c/0x48
uart_write+0xd8/0x3a0
do_output_char+0x1a8/0x1e4
n_tty_write+0x224/0x440
file_tty_write.constprop.0+0x124/0x250
do_iter_readv_writev+0x100/0x1e0
vfs_writev+0xc4/0x448
do_writev+0x68/0xf8
ret_fast_syscall+0x0/0x1c
irq event stamp: 31593
hardirqs last enabled at (31593): [<c1150e48>] _raw_spin_unlock_irqrestore+0x44/0x48
hardirqs last disabled at (31592): [<c07f32f0>] clk_enable_lock+0x60/0x120
softirqs last enabled at (30334): [<c012d1d4>] handle_softirqs+0x2cc/0x478
softirqs last disabled at (30325): [<c012d510>] __irq_exit_rcu+0x120/0x15c
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&port_lock_key);
<Interrupt>
lock(&port_lock_key);
Fixes: 3c199ed5bd64 ("serial: imx: Grab port lock in imx_uart_enable_wakeup()")
Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20241210233613.2881264-1-xiaolei.wang@windriver.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit f9b11229b79c ("serial: 8250: Fix PM usage_count for console
handover") fixed one runtime PM usage counter balance problem that
occurs because .dev is not set during univ8250 setup preventing call to
pm_runtime_get_sync(). Later, univ8250_console_exit() will trigger the
runtime PM usage counter underflow as .dev is already set at that time.
Call pm_runtime_get_sync() to balance the RPM usage counter also in
serial8250_register_8250_port() before trying to add the port.
Reported-by: Borislav Petkov (AMD) <bp@alien8.de>
Fixes: bedb404e91bb ("serial: 8250_port: Don't use power management for kernel console")
Cc: stable <stable@kernel.org>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20241210170120.2231-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The role of @read_status_mask has changed over time and seems
to still cause confusion. This can be expected since there is
zero documentation about this driver-specific variable.
Add comments to the initialization of @read_status_mask to
clarify its role.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20241216171244.12783-5-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The CREAD feature of termios is implemented by setting/clearing
UART_LSR_DR within @ignore_status_mask. For this feature to
function correctly, it requires that UART_LSR_DR is never
masked (unset) in @read_status_mask so that uart_insert_char()
can properly drop the character if CREAD is disabled.
Currently there are code paths that clear/set UART_LSR_DR from
@read_status_mask at times. This appears to be a relic from
Linux 1.1.60, where @read_status_mask could be used to mask
all UART_LSR reading. However, since Linux 2.1.8 that is no
longer the case. Now if UART_LSR_DR is cleared from
@read_status_mask, received characters may not be dropped
even though CREAD is disabled.
This can be seen when:
- CREAD is disabled (UART_LSR_DR is set in @ignore_status_mask)
- LSR has an error bit set from UART_LSR_BRK_ERROR_BITS
(and that error is not ignored via @ignore_status_mask)
- UART_LSR_DR is cleared in @read_status_mask
In this case characters will be inserted into the tty buffer
even though they should be ignored.
Remove all setting/clearing of UART_LSR_DR for
@read_status_mask except for its initialization.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20241216171244.12783-4-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since Linux 2.1.8 @read_status_mask is no longer used as a
general control of which bits are used from the LSR register.
Instead it has become an additional mask applied to
@ignore_status_mask. Since UART_LSR_THRE is never set for
@ignore_status_mask, it serves no purpose to set it for
@read_status_mask. In fact, it propagates the misconception
that @read_status_mask can be used as a general mask for LSR
bits.
Do not set UART_LSR_THRE for @read_status_mask.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20241216171244.12783-3-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit f19c3f6c8109 ("serial: 8250_port: Don't service RX FIFO if
throttled") uses @read_status_mask (bit UART_LSR_DR) to determine
if Rx has been stopped. However, the bit UART_LSR_DR is not
managed properly in @read_status_mask for all Rx stop/start
situations and is therefore not suitable for this purpose.
Use the UART_IER_RLSI and UART_IER_RDI bits in @ier instead, as
this is already common in 8250-variants and drivers.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20241216171244.12783-2-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the B0 revision, the RTS pin remains high due to incorrect hardware
mapping. To address this issue, enable auto-direction control with the
RTS bit in ADCL_CFG_REG. This configuration ensures that the RTS pin
goes low when the terminal is opened and high when the terminal is
closed. Additionally, we reset the step counter for Rx and Tx engines
by writing into FRAC_DIV_CFG_REG.
Signed-off-by: Rengarajan S <rengarajan.s@microchip.com>
Link: https://lore.kernel.org/r/20241218094017.18290-1-rengarajan.s@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are two small serial driver fixes for 6.13-rc3. They are:
- ioport build fallout fix for the 8250 port driver that should
resolve Guenter's runtime problems
- sh-sci driver bugfix for a reported problem
Both of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull serial driver fixes from Greg KH:
"Here are two small serial driver fixes for 6.13-rc3. They are:
- ioport build fallout fix for the 8250 port driver that should
resolve Guenter's runtime problems
- sh-sci driver bugfix for a reported problem
Both of these have been in linux-next for a while with no reported
issues"
* tag 'tty-6.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: serial: Work around warning backtrace in serial8250_set_defaults
serial: sh-sci: Check if TX data was written to device in .tx_empty()
Since commit 7abc9b53bd51 ("sysctl: allow registration of const struct
ctl_table"), the sysctl registration API allows for struct ctl_table to be
in read-only memory. Move tty_table to be declared at build time, instead
of having to be dynamically allocated at boot time.
Cc: Thomas Weißschuh <linux@weissschuh.net>
Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Ricardo B. Marliere <rbm@suse.com>
Link: https://lore.kernel.org/r/20241213-sysctl_const-tty-v1-1-2e2bcec77f85@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This "change_port" part of uart_set_info() is for no good reason
inlined there. It makes the function rather hard to read. Therefore,
extract it to a separate function.
This allows for flattening the ifs (with short path "return"s) and
avoiding two levels of indentation. Both making the code really flat and
comprehesible.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20241211074933.92973-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The label is unneeded since 7ba2e769825f (tty: Split the serial_core
helpers for setserial into two). Until then, there was a lock held in
uart_set_info().
Now it is not, so we can remove the label. This involves reordering the
code, so that it is clear what values are returned, where and why. Until
now, it was really hard to follow.
The "change_port" part of the function is extracted into a separate
function in the next patch. This patch makes the transition there easier
too.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20241211074933.92973-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Simplify 4 more functions using guard(mutex): uart_get_info(),
console_store(), serial_core_add_one_port(), and
serial_core_register_port(). Especially console_store() is now much less
convoluted. In the others, we save some goto-s and even local variables
are dropped in some.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20241211074933.92973-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need to redefine the driver name. Use KBUILD_MODNAME and get
rid of DRV_NAME altogether.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Link: https://lore.kernel.org/r/20241205091138.25894-1-tklauser@distanz.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 7c7e6c8924e7 ("tty: serial: handle HAS_IOPORT dependencies")
triggers warning backtraces on a number of platforms which don't support
IO ports.
WARNING: CPU: 0 PID: 0 at drivers/tty/serial/8250/8250_port.c:470 serial8250_set_defaults+0x148/0x1d8
Unsupported UART type 0
The problem is seen because serial8250_set_defaults() is called for
all members of the serial8250_ports[] array even if that array is
not initialized.
Work around the problem by only displaying the warning if the port
type is not 0 (UPIO_PORT) or if iobase is set for the port.
Fixes: 7c7e6c8924e7 ("tty: serial: handle HAS_IOPORT dependencies")
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Stafford Horne <shorne@gmail.com>
Link: https://lore.kernel.org/r/20241205143033.2695333-1-linux@roeck-us.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On the Renesas RZ/G3S, when doing suspend to RAM, the uart_suspend_port()
is called. The uart_suspend_port() calls 3 times the
struct uart_port::ops::tx_empty() before shutting down the port.
According to the documentation, the struct uart_port::ops::tx_empty()
API tests whether the transmitter FIFO and shifter for the port is
empty.
The Renesas RZ/G3S SCIFA IP reports the number of data units stored in the
transmit FIFO through the FDR (FIFO Data Count Register). The data units
in the FIFOs are written in the shift register and transmitted from there.
The TEND bit in the Serial Status Register reports if the data was
transmitted from the shift register.
In the previous code, in the tx_empty() API implemented by the sh-sci
driver, it is considered that the TX is empty if the hardware reports the
TEND bit set and the number of data units in the FIFO is zero.
According to the HW manual, the TEND bit has the following meaning:
0: Transmission is in the waiting state or in progress.
1: Transmission is completed.
It has been noticed that when opening the serial device w/o using it and
then switch to a power saving mode, the tx_empty() call in the
uart_port_suspend() function fails, leading to the "Unable to drain
transmitter" message being printed on the console. This is because the
TEND=0 if nothing has been transmitted and the FIFOs are empty. As the
TEND=0 has double meaning (waiting state, in progress) we can't
determined the scenario described above.
Add a software workaround for this. This sets a variable if any data has
been sent on the serial console (when using PIO) or if the DMA callback has
been called (meaning something has been transmitted). In the tx_empty()
API the status of the DMA transaction is also checked and if it is
completed or in progress the code falls back in checking the hardware
registers instead of relying on the software variable.
Fixes: 73a19e4c0301 ("serial: sh-sci: Add DMA support.")
Cc: stable@vger.kernel.org
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Link: https://lore.kernel.org/r/20241125115856.513642-1-claudiu.beznea.uj@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
parport_serial driver uses subset of WCH IDs that are present in 8250_pci.
Share them via pci_ids.h and switch parport_serial to use defined constants.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20241204031114.1029882-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are two sites of the same brand: wch.cn and wch-ic.com.
They are property of the same company, but it appears that they
managed to get two different PCI vendor IDs. Rename them accordingly
using standard pattern, i.e. PCI_VENDOR_ID_...
While at it, move to PCI_VDEVICE() in the ID tables.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20241204031114.1029882-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial8250_init_port() assings 0xFF for the unset or unknown port
IO type, use predefined constant for that instead.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20241125103305.1614986-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Using memcpy() prevents the compiler from doing any checking on the
types of the passed pointer parameters. Copy the structure using struct
assignment instead, to increase type-safety.
No change in generated code on all relevant architectures
(arm/arm64/riscv/sh).
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/e097e5c11afe5bd4c01135779c9a40e707ef6374.1733243287.git.geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The request_irq name parameter should be the device name, not the driver
name. This leads to more informative information in /proc/interrupts.
Before this patch:
$ cat /proc/interrupts
...
40: 123 0 GIC-0 72 Level altera_jtaguart
After this patch:
$ cat /proc/interrupts
...
40: 6 0 GIC-0 72 Level ff200100.fpga-juart0
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Link: https://lore.kernel.org/r/20241203132556.14182-1-tklauser@distanz.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit cdd30ebb1b9f ("module: Convert symbol namespace to string
literal") only converted MODULE_IMPORT_NS() and EXPORT_SYMBOL_NS(),
leaving DEFAULT_SYMBOL_NAMESPACE as a macro expansion.
This commit converts DEFAULT_SYMBOL_NAMESPACE in the same way to avoid
annoyance for the default namespace as well.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
