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8585 commits

Author SHA1 Message Date
Linus Torvalds
868a9fd948 TTY/Serial driver updates for 6.5-rc1.
Here is the big set of tty/serial driver updates for 6.5-rc1.
 
 Included in here are:
   - tty_audit code cleanups from Jiri
   - more 8250 cleanups from Ilpo
   - samsung_tty driver bugfixes
   - 8250 lock port updates
   - usual fsl_lpuart driver updates and fixes
   - other small serial driver fixes and updates, full details in the
     shortlog.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the big set of tty/serial driver updates for 6.5-rc1.

  Included in here are:

   - tty_audit code cleanups from Jiri

   - more 8250 cleanups from Ilpo

   - samsung_tty driver bugfixes

   - 8250 lock port updates

   - usual fsl_lpuart driver updates and fixes

   - other small serial driver fixes and updates, full details in the
     shortlog

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (58 commits)
  tty_audit: make data of tty_audit_log() const
  tty_audit: make tty pointers in exposed functions const
  tty_audit: make icanon a bool
  tty_audit: invert the condition in tty_audit_log()
  tty_audit: use kzalloc() in tty_audit_buf_alloc()
  tty_audit: use TASK_COMM_LEN for task comm
  Revert "8250: add support for ASIX devices with a FIFO bug"
  serial: atmel: don't enable IRQs prematurely
  tty: serial: Add Nuvoton ma35d1 serial driver support
  tty: serial: fsl_lpuart: add earlycon for imx8ulp platform
  tty: serial: imx: fix rs485 rx after tx
  selftests: tty: add selftest for tty timestamp updates
  tty: tty_io: update timestamps on all device nodes
  tty: fix hang on tty device with no_room set
  serial: core: fix -EPROBE_DEFER handling in init
  serial: 8250_omap: Use force_suspend and resume for system suspend
  tty: serial: samsung_tty: Use abs() to simplify some code
  tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() when iterating clk
  tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() in case of error
  serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLE
  ...
2023-07-03 13:14:58 -07:00
Linus Torvalds
fc75f21645 driver core changes for 6.5-rc1
Here are a small set of changes for 6.5-rc1 for some driver core
 changes.  Included in here are:
   - device property cleanups to make it easier to write "agnostic"
     drivers when regards to the firmware layer underneath them (DT vs.
     ACPI)
   - debugfs documentation updates
   - devres additions
   - sysfs documentation and changes to handle empty directory creation
     logic better
   - tiny kernfs optimizations
   - other tiny changes
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here are a small set of changes for 6.5-rc1 for some driver core
  changes. Included in here are:

   - device property cleanups to make it easier to write "agnostic"
     drivers when regards to the firmware layer underneath them (DT vs.
     ACPI)

   - debugfs documentation updates

   - devres additions

   - sysfs documentation and changes to handle empty directory creation
     logic better

   - tiny kernfs optimizations

   - other tiny changes

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'driver-core-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  sysfs: Skip empty folders creation
  sysfs: Improve readability by following the kernel coding style
  drivers: fwnode: fix fwnode_irq_get[_byname]()
  ata: ahci_platform: Make code agnostic to OF/ACPI
  device property: Implement device_is_compatible()
  ACPI: Move ACPI_DEVICE_CLASS() to mod_devicetable.h
  base/node: Use 'property' to identify an access parameter
  driver core: device.h: add some missing kerneldocs
  kernfs: fix missing kernfs_idr_lock to remove an ID from the IDR
  isa: Remove unnecessary checks
  MAINTAINERS: add entry for auxiliary bus
  debugfs: Correct the 'debugfs_create_str' docs
  serial: qcom_geni: Comment use of devm_krealloc rather than devm_krealloc_array
  iio: adc: Use devm_krealloc_array
  hwmon: pmbus: Use devm_krealloc_array
2023-07-03 12:56:23 -07:00
Linus Torvalds
04fc8904d5 Move the Arm architecture documentation under Documentation/arch/. This
brings some order to the documentation directory, declutters the top-level
 directory, and makes the documentation organization more closely match that
 of the source.
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Merge tag 'docs-arm-move' of git://git.lwn.net/linux

Pull arm documentation move from Jonathan Corbet:
 "Move the Arm architecture documentation under Documentation/arch/.

  This brings some order to the documentation directory, declutters the
  top-level directory, and makes the documentation organization more
  closely match that of the source"

* tag 'docs-arm-move' of git://git.lwn.net/linux:
  dt-bindings: Update Documentation/arm references
  docs: update some straggling Documentation/arm references
  crypto: update some Arm documentation references
  mips: update a reference to a moved Arm Document
  arm64: Update Documentation/arm references
  arm: update in-source documentation references
  arm: docs: Move Arm documentation to Documentation/arch/
2023-06-27 11:58:16 -07:00
Linus Torvalds
3eccc0c886 for-6.5/splice-2023-06-23
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Merge tag 'for-6.5/splice-2023-06-23' of git://git.kernel.dk/linux

Pull splice updates from Jens Axboe:
 "This kills off ITER_PIPE to avoid a race between truncate,
  iov_iter_revert() on the pipe and an as-yet incomplete DMA to a bio
  with unpinned/unref'ed pages from an O_DIRECT splice read. This causes
  memory corruption.

  Instead, we either use (a) filemap_splice_read(), which invokes the
  buffered file reading code and splices from the pagecache into the
  pipe; (b) copy_splice_read(), which bulk-allocates a buffer, reads
  into it and then pushes the filled pages into the pipe; or (c) handle
  it in filesystem-specific code.

  Summary:

   - Rename direct_splice_read() to copy_splice_read()

   - Simplify the calculations for the number of pages to be reclaimed
     in copy_splice_read()

   - Turn do_splice_to() into a helper, vfs_splice_read(), so that it
     can be used by overlayfs and coda to perform the checks on the
     lower fs

   - Make vfs_splice_read() jump to copy_splice_read() to handle
     direct-I/O and DAX

   - Provide shmem with its own splice_read to handle non-existent pages
     in the pagecache. We don't want a ->read_folio() as we don't want
     to populate holes, but filemap_get_pages() requires it

   - Provide overlayfs with its own splice_read to call down to a lower
     layer as overlayfs doesn't provide ->read_folio()

   - Provide coda with its own splice_read to call down to a lower layer
     as coda doesn't provide ->read_folio()

   - Direct ->splice_read to copy_splice_read() in tty, procfs, kernfs
     and random files as they just copy to the output buffer and don't
     splice pages

   - Provide wrappers for afs, ceph, ecryptfs, ext4, f2fs, nfs, ntfs3,
     ocfs2, orangefs, xfs and zonefs to do locking and/or revalidation

   - Make cifs use filemap_splice_read()

   - Replace pointers to generic_file_splice_read() with pointers to
     filemap_splice_read() as DIO and DAX are handled in the caller;
     filesystems can still provide their own alternate ->splice_read()
     op

   - Remove generic_file_splice_read()

   - Remove ITER_PIPE and its paraphernalia as generic_file_splice_read
     was the only user"

* tag 'for-6.5/splice-2023-06-23' of git://git.kernel.dk/linux: (31 commits)
  splice: kdoc for filemap_splice_read() and copy_splice_read()
  iov_iter: Kill ITER_PIPE
  splice: Remove generic_file_splice_read()
  splice: Use filemap_splice_read() instead of generic_file_splice_read()
  cifs: Use filemap_splice_read()
  trace: Convert trace/seq to use copy_splice_read()
  zonefs: Provide a splice-read wrapper
  xfs: Provide a splice-read wrapper
  orangefs: Provide a splice-read wrapper
  ocfs2: Provide a splice-read wrapper
  ntfs3: Provide a splice-read wrapper
  nfs: Provide a splice-read wrapper
  f2fs: Provide a splice-read wrapper
  ext4: Provide a splice-read wrapper
  ecryptfs: Provide a splice-read wrapper
  ceph: Provide a splice-read wrapper
  afs: Provide a splice-read wrapper
  9p: Add splice_read wrapper
  net: Make sock_splice_read() use copy_splice_read() by default
  tty, proc, kernfs, random: Use copy_splice_read()
  ...
2023-06-26 11:52:12 -07:00
Jiri Slaby
e534755c94 tty_audit: make data of tty_audit_log() const
'data' are only read (passed down to audit_log_n_hex()), so they can be
const -- the same what is expected in audit_log_n_hex(). Only a minor
cleanup to be consistent.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-7-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiri Slaby
e64ed44bce tty_audit: make tty pointers in exposed functions const
Both tty_audit_add_data() and tty_audit_tiocsti() need only to read from
the tty struct, so make the tty parameters of them both const. This
aids the compiler a bit.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-6-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiri Slaby
3e540a7bad tty_audit: make icanon a bool
Use bool for tty_audit_buf::icanon in favor of ugly bitfields. And get
rid of "!!" as that is completely unnecessary.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-5-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiri Slaby
94f94810ef tty_audit: invert the condition in tty_audit_log()
If we cannot obtain an audit buffer in tty_audit_log(), simply return
from the function. Apart this is mostly preferred in the kernel, it
allows to merge the split audit string while still keeping it readable.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiri Slaby
e1488513ab tty_audit: use kzalloc() in tty_audit_buf_alloc()
tty_audit_buf_alloc() manually erases most of the entries after
kmalloc(). So use kzalloc() and remove the manual sets to zero.

That way, we are sure that we do not omit anything.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiri Slaby
777e456852 tty_audit: use TASK_COMM_LEN for task comm
This is the preferred way of declaring an array for get_task_comm().

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiaqing Zhao
a82d62f708 Revert "8250: add support for ASIX devices with a FIFO bug"
This reverts commit eb26dfe8aa.

Commit eb26dfe8aa ("8250: add support for ASIX devices with a FIFO
bug") merged on Jul 13, 2012 adds a quirk for PCI_VENDOR_ID_ASIX
(0x9710). But that ID is the same as PCI_VENDOR_ID_NETMOS defined in
1f8b061050c7 ("[PATCH] Netmos parallel/serial/combo support") merged
on Mar 28, 2005. In pci_serial_quirks array, the NetMos entry always
takes precedence over the ASIX entry even since it was initially
merged, code in that commit is always unreachable.

In my tests, adding the FIFO workaround to pci_netmos_init() makes no
difference, and the vendor driver also does not have such workaround.
Given that the code was never used for over a decade, it's safe to
revert it.

Also, the real PCI_VENDOR_ID_ASIX should be 0x125b, which is used on
their newer AX99100 PCIe serial controllers released on 2016. The FIFO
workaround should not be intended for these newer controllers, and it
was never implemented in vendor driver.

Fixes: eb26dfe8aa ("8250: add support for ASIX devices with a FIFO bug")
Cc: stable <stable@kernel.org>
Signed-off-by: Jiaqing Zhao <jiaqing.zhao@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230619155743.827859-1-jiaqing.zhao@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:55:53 +02:00
Dan Carpenter
27a826837e serial: atmel: don't enable IRQs prematurely
The atmel_complete_tx_dma() function disables IRQs at the start
of the function by calling spin_lock_irqsave(&port->lock, flags);
There is no need to disable them a second time using the
spin_lock_irq() function and, in fact, doing so is a bug because
it will enable IRQs prematurely when we call spin_unlock_irq().

Just use spin_lock/unlock() instead without disabling or enabling
IRQs.

Fixes: 08f738be88 ("serial: at91: add tx dma support")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Link: https://lore.kernel.org/r/cb7c39a9-c004-4673-92e1-be4e34b85368@moroto.mountain
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:54:33 +02:00
Jacky Huang
930cbf92db tty: serial: Add Nuvoton ma35d1 serial driver support
This adds UART and console driver for Nuvoton ma35d1 Soc.
It supports full-duplex communication, FIFO control, and
hardware flow control.
Command line set "console=ttyNVT0,115200", NVT means
Nuvoton MA35 UART port. The UART driver probe will
create path named "/dev/ttyNVTx".

Signed-off-by: Jacky Huang <ychuang3@nuvoton.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230619032330.233796-2-ychuang570808@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-19 15:42:26 +02:00
Sherry Sun
e0edfdc158 tty: serial: fsl_lpuart: add earlycon for imx8ulp platform
Add earlycon support for imx8ulp platform.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20230619080613.16522-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-19 15:41:25 +02:00
Martin Fuzzey
639949a703 tty: serial: imx: fix rs485 rx after tx
Since commit 79d0224f6b ("tty: serial: imx: Handle RS485 DE signal
active high") RS485 reception no longer works after a transmission.

The following scenario shows the problem:
	1) Open a port in RS485 mode
	2) Receive data from remote (OK)
	3) Transmit data to remote (OK)
	4) Receive data from remote (Nothing received)

In RS485 mode, imx_uart_start_tx() calls imx_uart_stop_rx() and, when the
transmission is complete, imx_uart_stop_tx() calls imx_uart_start_rx().

Since the above commit imx_uart_stop_rx() now sets the loopback bit but
imx_uart_start_rx() does not clear it causing the hardware to remain in
loopback mode and not receive external data.

Fix this by moving the existing loopback disable code to a helper function
and calling it from imx_uart_start_rx() too.

Fixes: 79d0224f6b ("tty: serial: imx: Handle RS485 DE signal active high")
Cc: stable@vger.kernel.org
Signed-off-by: Martin Fuzzey <martin.fuzzey@flowbird.group>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230616104838.2729694-1-martin.fuzzey@flowbird.group
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-19 15:41:13 +02:00
Jonathan Corbet
173cb655ea docs: update some straggling Documentation/arm references
The Arm documentation has moved to Documentation/arch/arm; update the
last remaining references to match.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Samuel Holland <samuel@sholland.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # for pwm
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-06-16 08:31:47 -06:00
Michal Sekletar
360c11e225 tty: tty_io: update timestamps on all device nodes
User space applications watch for timestamp changes on character device
files in order to determine idle time of a given terminal session. For
example, "w" program uses this information to populate the IDLE column
of its output [1]. Similarly, systemd-logind has optional feature where
it uses atime of the tty character device to determine if there was
activity on the terminal associated with the logind's session object. If
there was no activity for a configured period of time then logind will
terminate such session [2].

Now, usually (e.g. bash running on the terminal) the use of the terminal
will update timestamps (atime and mtime) on the corresponding terminal
character device. However, if access to the terminal, e.g. /dev/pts/0,
is performed through magic character device /dev/tty then such access
obviously changes the state of the terminal, however timestamps on the
device that correspond to the terminal (/dev/pts/0) are not updated.

This patch makes sure that we update timestamps on *all* character
devices that correspond to the given tty, because outside observers (w,
systemd-logind) are maybe checking these timestamps. Obviously, they can
not check timestamps on /dev/tty as that has per-process meaning.

[1] https://gitlab.com/procps-ng/procps/-/blob/v4.0.0/w.c#L286
[2] https://github.com/systemd/systemd/blob/v252/NEWS#L477

Signed-off-by: Michal Sekletar <msekleta@redhat.com>
Message-ID: <20230613172107.78138-1-msekleta@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15 13:45:42 +02:00
Hui Li
4903fde804 tty: fix hang on tty device with no_room set
It is possible to hang pty devices in this case, the reader was
blocking at epoll on master side, the writer was sleeping at
wait_woken inside n_tty_write on slave side, and the write buffer
on tty_port was full, we found that the reader and writer would
never be woken again and blocked forever.

The problem was caused by a race between reader and kworker:
n_tty_read(reader):  n_tty_receive_buf_common(kworker):
copy_from_read_buf()|
                    |room = N_TTY_BUF_SIZE - (ldata->read_head - tail)
                    |room <= 0
n_tty_kick_worker() |
                    |ldata->no_room = true

After writing to slave device, writer wakes up kworker to flush
data on tty_port to reader, and the kworker finds that reader
has no room to store data so room <= 0 is met. At this moment,
reader consumes all the data on reader buffer and calls
n_tty_kick_worker to check ldata->no_room which is false and
reader quits reading. Then kworker sets ldata->no_room=true
and quits too.

If write buffer is not full, writer will wake kworker to flush data
again after following writes, but if write buffer is full and writer
goes to sleep, kworker will never be woken again and tty device is
blocked.

This problem can be solved with a check for read buffer size inside
n_tty_receive_buf_common, if read buffer is empty and ldata->no_room
is true, a call to n_tty_kick_worker is necessary to keep flushing
data to reader.

Cc: <stable@vger.kernel.org>
Fixes: 42458f41d0 ("n_tty: Ensure reader restarts worker for next reader")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Hui Li <caelli@tencent.com>
Message-ID: <1680749090-14106-1-git-send-email-caelli@tencent.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15 12:21:11 +02:00
Dan Carpenter
cef09673c3 serial: core: fix -EPROBE_DEFER handling in init
The -EPROBE_DEFER error path in serial_base_device_init() is a bit
awkward.  Before the call to device_initialize(dev) then we need to
manually release all the device resources.  And after the call then we
need to call put_device() to release the resources.  Doing either one
wrong will result in a leak or a use after free.

So let's wait to return -EPROBE_DEFER until after the call to
device_initialize(dev) so that way callers do not have to handle
-EPROBE_DEFER as a special case.  Now callers can just use put_device()
for clean up.

The second issue with the -EPROBE_DEFER path is that deferring is not
supposed to be a fatal error, but instead it's normal part of the
init process and the kernel recovers from it automatically.  That means
we should not print an error message but just a debug message on this
path.

Fixes: 539914240a ("serial: core: Fix probing serial_base_bus devices")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Message-ID: <18318adb-ab2c-4dcc-9f96-498a13d16b80@moroto.mountain>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15 12:20:51 +02:00
Tony Lindgren
20a41a6261 serial: 8250_omap: Use force_suspend and resume for system suspend
We should not rely on autosuspend timeout for system suspend. Instead,
let's use force_suspend and force_resume functions. Otherwise the serial
port controller device may not be idled on suspend.

As we are doing a register write on suspend to configure the serial port,
we still need to runtime PM resume the port on suspend.

While at it, let's switch to pm_runtime_resume_and_get() and check for
errors returned. And let's add the missing line break before return to the
suspend function while at it.

Fixes: 09d8b2bdbc ("serial: 8250: omap: Provide ability to enable/disable UART as wakeup source")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Dhruva Gole <d-gole@ti.com>
Message-ID: <20230614045922.4798-1-tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15 12:20:49 +02:00
Christophe JAILLET
f3710f5e9e tty: serial: samsung_tty: Use abs() to simplify some code
Use abs() instead of hand-writing it.

Suggested-by: Walter Harms <wharms@bfs.de>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Message-ID: <7bd165e82ed3675d4ddee343ab373031e995a126.1686412569.git.christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:33:22 +02:00
Christophe JAILLET
832e231cff tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() when iterating clk
When the best clk is searched, we iterate over all possible clk.

If we find a better match, the previous one, if any, needs to be freed.
If a better match has already been found, we still need to free the new
one, otherwise it leaks.

Cc: <stable@vger.kernel.org> # v3.3+
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Fixes: 5f5a7a5578 ("serial: samsung: switch to clkdev based clock lookup")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Message-ID: <cf3e0053d2fc7391b2d906a86cd01a5ef15fb9dc.1686412569.git.christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:33:22 +02:00
Christophe JAILLET
a9c09546e9 tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() in case of error
If clk_get_rate() fails, the clk that has just been allocated needs to be
freed.

Cc: <stable@vger.kernel.org> # v3.3+
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Fixes: 5f5a7a5578 ("serial: samsung: switch to clkdev based clock lookup")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Message-ID: <e4baf6039368f52e5a5453982ddcb9a330fc689e.1686412569.git.christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:33:22 +02:00
Robert Hodaszi
a82c3df955 tty: serial: fsl_lpuart: reduce RX watermark to 0 on LS1028A
LS1028A is using DMA with LPUART. Having RX watermark set to 1, means
DMA transactions are started only after receiving the second character.

On other platforms with newer LPUART IP, Receiver Idle Empty function
initiates the DMA request after the receiver is idling for 4 characters.
But this feature is missing on LS1028A, which is causing a 1-character
delay in the RX direction on this platform.

Set RX watermark to 0 to initiate RX DMA after each character.

Link: https://lore.kernel.org/linux-serial/20230607103459.1222426-1-robert.hodaszi@digi.com/
Fixes: 9ad9df8447 ("tty: serial: fsl_lpuart: Fix the wrong RXWATER setting for rx dma case")
Cc: stable <stable@kernel.org>
Signed-off-by: Robert Hodaszi <robert.hodaszi@digi.com>
Message-ID: <20230609121334.1878626-1-robert.hodaszi@digi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:31:45 +02:00
Uwe Kleine-König
d9f59caf94 serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLE
The need to handle the FSL variant of 8250 in a special way is also
present without console support. So soften the dependency for
SERIAL_8250_FSL from SERIAL_8250_CONSOLE to SERIAL_8250. To handle
SERIAL_8250=m, the FSL code can be modular, too, thus SERIAL_8250_FSL
becomes tristate.

Compiling 8250_fsl as a module requires adding a module license so this
is added, too. While add it also add a appropriate module description.

As then SERIAL_OF_PLATFORM=y + SERIAL_8250_FSL=m is a valid combination
(if COMPILE_TEST is enabled on a platform that is neither PPC, ARM nor
ARM64), the check in 8250_of.c must be weakened a bit.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Message-ID: <20230609133932.786117-3-u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:27:05 +02:00
Dan Carpenter
52861a3be8 serial: core: don't kfree device managed data
The put_device() function will call serial_base_ctrl_release() or
serial_base_port_release() so these kfrees() are a double free bug.

Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Message-ID: <ZH7tsTmWY5b/4m+6@moroto>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-06 14:46:35 +02:00
Bernhard Seibold
306320034e serial: lantiq: add missing interrupt ack
Currently, the error interrupt is never acknowledged, so once active it
will stay active indefinitely, causing the handler to be called in an
infinite loop.

Fixes: 2f0fc4159a ("SERIAL: Lantiq: Add driver for MIPS Lantiq SOCs.")
Cc: <stable@vger.kernel.org>
Signed-off-by: Bernhard Seibold <mail@bernhard-seibold.de>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Message-ID: <20230602133029.546-1-mail@bernhard-seibold.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-06 14:45:34 +02:00
Chen-Yu Tsai
b6c7ff2693 serial: 8250_mtk: Simplify clock sequencing and runtime PM
The 8250_mtk driver's runtime PM support has some issues:

- The bus clock is enabled (through runtime PM callback) later than a
  register write
- runtime PM resume callback directly called in probe, but no
  pm_runtime_set_active() call is present
- UART PM function calls the callbacks directly, _and_ calls runtime
  PM API
- runtime PM callbacks try to do reference counting, adding yet another
  count between runtime PM and clocks

This fragile setup worked in a way, but broke recently with runtime PM
support added to the serial core. The system would hang when the UART
console was probed and brought up.

Tony provided some potential fixes [1][2], though they were still a bit
complicated. The 8250_dw driver, which the 8250_mtk driver might have
been based on, has a similar structure but simpler runtime PM usage.

Simplify clock sequencing and runtime PM support in the 8250_mtk driver.
Specifically, the clock is acquired enabled and assumed to be active,
unless toggled through runtime PM suspend/resume. Reference counting is
removed and left to the runtime PM core. The serial pm function now
only calls the runtime PM API.

[1] https://lore.kernel.org/linux-serial/20230602092701.GP14287@atomide.com/
[2] https://lore.kernel.org/linux-serial/20230605061511.GW14287@atomide.com/

Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Suggested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Message-ID: <20230606091747.2031168-1-wenst@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-06 14:43:13 +02:00
Raphael Gallais-Pou
643662d12b serial: st-asc: fix typo in property name
Changes the property name read in the driver according to the YAML.
According to device-tree documentation, property names should not
include underscores.

Signed-off-by: Raphael Gallais-Pou <rgallaispou@gmail.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Message-ID: <20230604083558.16661-1-rgallaispou@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-06 14:42:58 +02:00
Greg Kroah-Hartman
2076b2a4a6 Merge 6.4-rc5 into tty-next
We need the tty fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-05 07:41:04 +02:00
Greg Kroah-Hartman
16b58423b4 Merge 6.4-rc5 into driver-core-next
We need the driver core fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-05 07:37:37 +02:00
Tony Lindgren
49c80922ff serial: core: Fix error handling for serial_core_ctrl_device_add()
Checking for NULL is incorrect as serial_base_ctrl_add() uses ERR_PTR().

Let's also pass any returned error along, there's no reason to translate
all errors to -ENODEV.

Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230602070007.59268-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-02 08:30:55 +01:00
Tony Lindgren
539914240a serial: core: Fix probing serial_base_bus devices
If a physical serial port device driver uses arch_initcall() we fail to
probe the serial_base_bus devices and the serial port tx fails. This is
because as serial_base_bus uses module_initcall().

Let's fix the issue by changing serial_base_bus to use arch_initcall().

Let's also return an error if a driver attempts to call uart_add_one_port()
too early.

Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Closes: https://lore.kernel.org/linux-serial/20230601132012.GB14287@atomide.com/T/#m6a40440fc04d551d27b147da8602e065c982a115
Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230601141445.11321-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-01 16:45:50 +01:00
Steven Price
d0a396083e serial: core: Don't drop port_mutex in serial_core_remove_one_port
Commit 84a9582fd2 ("serial: core: Start managing serial controllers to
enable runtime PM") required the caller to hold port_mutex rather than
taking it locally. However the mutex_unlock() call wasn't removed
causing the mutex to be dropped unexpectly. Remove the call to
mutex_unlock() (and fix up the early return) to restore correct
behaviour.

Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Signed-off-by: Steven Price <steven.price@arm.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230601105548.29965-1-steven.price@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-01 14:04:01 +01:00
Tony Lindgren
84a9582fd2 serial: core: Start managing serial controllers to enable runtime PM
We want to enable runtime PM for serial port device drivers in a generic
way. To do this, we want to have the serial core layer manage the
registered physical serial controller devices.

To manage serial controllers, let's set up a struct bus and struct device
for the serial core controller as suggested by Greg and Jiri. The serial
core controller devices are children of the physical serial port device.
The serial core controller device is needed to support multiple different
kind of ports connected to single physical serial port device.

Let's also set up a struct device for the serial core port. The serial
core port instances are children of the serial core controller device.

With the serial core port device we can now flush pending TX on the
runtime PM resume as suggested by Johan.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Jiri Slaby <jirislaby@kernel.org>
Suggested-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230525113034.46880-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-31 10:46:59 +01:00
Arnd Bergmann
ae62c49c0c serial: 8250: omap: convert to modern PM ops
The new uart_write() function is only called from suspend/resume code, causing
a build warning when those are left out:

drivers/tty/serial/8250/8250_omap.c:169:13: error: 'uart_write' defined but not used [-Werror=unused-function]

Remove the #ifdefs and use the modern pm_ops/pm_sleep_ops and their wrappers
to let the compiler see where it's used but still drop the dead code.

Fixes: 398cecc248 ("serial: 8250: omap: Fix imprecise external abort for omap_8250_pm()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230517202012.634386-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-31 10:46:59 +01:00
Geert Uytterhoeven
c53aab2076 serial: 8250: omap: Move uart_write() inside PM section
If CONFIG_PM is not set (e.g. m68k/allmodconfig):

    drivers/tty/serial/8250/8250_omap.c:169:13: error: ‘uart_write’ defined but not used [-Werror=unused-function]
      169 | static void uart_write(struct omap8250_priv *priv, u32 reg, u32 val)
	  |             ^~~~~~~~~~

Fix tis by moving uart_write() inside the existing section protected
by #ifdef CONFIG_PM.

Reported-by: noreply@ellerman.id.au
Link: http://kisskb.ellerman.id.au/kisskb/buildresult/14925095/
Fixes: 398cecc248 ("serial: 8250: omap: Fix imprecise external abort for omap_8250_pm()")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230515065706.1723477-1-geert@linux-m68k.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-31 10:46:59 +01:00
Uwe Kleine-König
d2d4bd217c serial: 8250-fsl: Expand description of the MPC83xx UART's misbehaviour
After working quite a bit on erratic behaviour of the MPC83xx UART I
(think I) understood the problem. Expand the description accoringly to
conserve the knowledge for the future.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230524122754.481816-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-31 10:46:59 +01:00
James Clark
9e6aa7c22d serial: qcom_geni: Comment use of devm_krealloc rather than devm_krealloc_array
Now that devm_krealloc_array is available, add a comment justifying not
changing this occurrence to avoid any future auto fixups.

Link: https://lore.kernel.org/all/20230318173402.20a4f60d@jic23-huawei/
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20230509094942.396150-5-james.clark@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 21:07:15 +01:00
Herve Codina
7183c37fd5 serial: cpm_uart: Fix a COMPILE_TEST dependency
In a COMPILE_TEST configuration, the cpm_uart driver uses symbols from
the cpm_uart_cpm2.c file. This file is compiled only when CONFIG_CPM2 is
set.

Without this dependency, the linker fails with some missing symbols for
COMPILE_TEST configuration that needs SERIAL_CPM without enabling CPM2.

This lead to:
  depends on CPM2 || CPM1 || (PPC32 && CPM2 && COMPILE_TEST)

This dependency does not make sense anymore and can be simplified
removing all the COMPILE_TEST part.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202305160221.9XgweObz-lkp@intel.com/
Fixes: e3e7b13bff ("serial: allow COMPILE_TEST for some drivers")
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20230523085902.75837-3-herve.codina@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 12:25:47 +01:00
Sherry Sun
2474e05467 tty: serial: fsl_lpuart: use UARTCTRL_TXINV to send break instead of UARTCTRL_SBK
LPUART IP now has two known bugs, one is that CTS has higher priority
than the break signal, which causes the break signal sending through
UARTCTRL_SBK may impacted by the CTS input if the HW flow control is
enabled. It exists on all platforms we support in this driver.
So we add a workaround patch for this issue: commit c4c81db5cf
("tty: serial: fsl_lpuart: disable the CTS when send break signal").

Another IP bug is i.MX8QM LPUART may have an additional break character
being sent after SBK was cleared. It may need to add some delay between
clearing SBK and re-enabling CTS to ensure that the SBK latch are
completely cleared.

But we found that during the delay period before CTS is enabled, there
is still a risk that Bluetooth data in TX FIFO may be sent out during
this period because of break off and CTS disabled(even if BT sets CTS
line deasserted, data is still sent to BT).

Due to this risk, we have to drop the CTS-disabling workaround for SBK
bugs, use TXINV seems to be a better way to replace SBK feature and
avoid above risk. Also need to disable the transmitter to prevent any
data from being sent out during break, then invert the TX line to send
break. Then disable the TXINV when turn off break and re-enable
transmitter.

Fixes: c4c81db5cf ("tty: serial: fsl_lpuart: disable the CTS when send break signal")
Cc: stable <stable@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20230519094751.28948-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 12:24:27 +01:00
Christophe JAILLET
134f49dec0 serial: 8250_tegra: Fix an error handling path in tegra_uart_probe()
If an error occurs after reset_control_deassert(), it must be re-asserted,
as already done in the .remove() function.

Fixes: c6825c6395 ("serial: 8250_tegra: Create Tegra specific 8250 driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/f8130f35339cc80edc6b9aac4bb2a60b60a226bf.1684063511.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 12:24:07 +01:00
James Hilliard
1b997aef4f serial: Indicate fintek option may also be required for RS232 support
The current config comment for SERIAL_8250_FINTEK implies that this
option is only needed when one wants to support RS485. As it turns
out we also need to enable this option for RS232 support to function
correctly on some variants.

For example for variants such as the F71869AD attempting to use
multiple RS232 ports simultaneously without this option enabled can
result in data corruption.

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Link: https://lore.kernel.org/r/20230521075046.3539376-1-james.hilliard1@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 11:51:04 +01:00
Sherry Sun
20ec397d69 tty: serial: fsl_lpuart: Check the return value of dmaengine_tx_status
Coverity reports the Unchecked return value (CHECKED_RETURN) warning:
Calling dmaengine_tx_status without checking return value.

So here add the return value check for dmaengine_tx_status() function to
make coverity happy.

Fixes: cf9aa72d2f ("tty: serial: fsl_lpuart: optimize the timer based EOP logic")
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20230522025111.3747-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 11:50:24 +01:00
Uwe Kleine-König
0d07703be7 serial: Switch i2c drivers back to use .probe()
After commit b8a1a4cd5a ("i2c: Provide a temporary .probe_new()
call-back type"), all drivers being converted to .probe_new() and then
03c835f498 ("i2c: Switch .probe() to not take an id parameter")
convert back to (the new) .probe() to be able to eventually drop
.probe_new() from struct i2c_driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230525210147.734737-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 11:46:05 +01:00
John Ogness
d0b309a5d3 serial: 8250: synchronize and annotate UART_IER access
The UART_IER register is modified twice by each console write
(serial8250_console_write()) under the port lock. Any driver code that
accesses UART_IER must do so with the port locked in order to ensure
consistent values, even when for read accesses.

Add locking, lockdep notation, and/or comments everywhere UART_IER is
accessed. The added locking is not fixing a real problem because it
occurs where the console is not active. However, adding the locking
to these non-critical paths greatly simplifies UART_IER access
tracking by establishing a general policy that all UART_IER access
is performed with the port locked.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20230525093159.223817-9-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 11:45:42 +01:00
John Ogness
25614735a6 serial: 8250: lock port for UART_IER access in omap8250_irq()
omap8250_irq() accesses UART_IER. This register is modified twice
by each console write (serial8250_console_write()) under the port
lock. omap8250_irq() must also take the port lock to guanentee
synchronized access to UART_IER.

Since the port lock is already being taken for the stop_rx() callback
and since it is safe to call cancel_delayed_work() while holding the
port lock, simply extend the port lock region to include UART_IER
access.

Fixes: 1fe0e1fa32 ("serial: 8250_omap: Handle optional overrun-throttle-ms property")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230525093159.223817-8-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 11:45:42 +01:00
John Ogness
8b45503776 serial: 8250: lock port for omap8250_restore_regs()
omap8250_restore_regs() accesses UART_IER. This register is
modified twice by each console write (serial8250_console_write())
under the port lock. However, not all calls to omap8250_restore_regs()
are under the port lock.

Add the missing port locking around omap8250_restore_regs() calls. Add
lockdep notation to the omap8250_restore_regs().

Note that this is not fixing a real problem because the serial devices
are resumed before console printing is enabled.

However, adding this locking allows for clean locking semantics
for omap8250_restore_regs() so that lockdep can be used to identify
possible problems in the future. It also simplifies synchronization
of UART_IER in general by not needing to rely on such implementation
details.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20230525093159.223817-7-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 11:45:42 +01:00
John Ogness
87660fb404 serial: 8250: lock port for rx_dma() callback
The rx_dma() callback (omap_8250_rx_dma) accesses UART_IER. This
register is modified twice by each console write
(serial8250_console_write()) under the port lock. However, not
all calls to the rx_dma() callback are under the port lock.

Add the missing port locking around rx_dma() callback calls. Add
lockdep notation to the omap_8250_rx_dma().

Note that this is not fixing a real problem because:

1. Currently DMA is forced off for 8250_omap consoles.

2. The serial devices are resumed before console printing is enabled.

However, adding this locking allows for clean locking semantics
for the rx_dma() callback so that lockdep can be used to identify
possible problems in the future. It also simplifies synchronization
of UART_IER in general by not needing to rely on implementation
details such as 1 and 2.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20230525093159.223817-6-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 11:45:42 +01:00
John Ogness
51e45fba14 serial: core: lock port for start_rx() in uart_resume_port()
The only user of the start_rx() callback (qcom_geni) directly calls
its own stop_rx() callback. Since stop_rx() requires that the
port->lock is taken and interrupts are disabled, the start_rx()
callback has the same requirement.

Fixes: cfab87c2c2 ("serial: core: Introduce callback for start_rx and do stop_rx in suspend only if this callback implementation is present.")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230525093159.223817-5-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30 11:45:42 +01:00