linux-stable.git/drivers/tty/serial/8250, branch linux-5.0.y

serial: 8250_pxa: honor the port number from devicetree

2019-04-05T20:34:29+00:00

[ Upstream commit fe9ed6d2483fda55465f32924fb15bce0fac3fac ]

Like the other OF-enabled drivers, use the port number from the firmware if
the devicetree specifies an alias:

  aliases {
      ...
      serial2 = &uart2; /* Should be ttyS2 */
  }

This is how the deprecated pxa.c driver behaved, switching to 8250_pxa
messes up the numbering.

Signed-off-by: Lubomir Rintel 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

serial: 8250_pci: Have ACCES cards that use the four port Pericom PI7C9X7954 chip use the pci_pericom_setup()

2019-03-23T19:11:30+00:00

commit 78d3820b9bd39028727c6aab7297b63c093db343 upstream.

The four port Pericom chips have the fourth port at the wrong address.
Make use of quirk to fix it.

Fixes: c8d192428f52 ("serial: 8250: added acces i/o products quad and octal serial cards")
Cc: stable 
Signed-off-by: Jay Dolan 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Fix number of ports for ACCES serial cards

2019-03-23T19:11:30+00:00

commit b896b03bc7fce43a07012cc6bf5e2ab2fddf3364 upstream.

Have the correct number of ports created for ACCES serial cards. Two port
cards show up as four ports, and four port cards show up as eight.

Fixes: c8d192428f52 ("serial: 8250: added acces i/o products quad and octal serial cards")
Signed-off-by: Jay Dolan 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_of: assume reg-shift of 2 for mrvl,mmp-uart

2019-03-23T19:11:30+00:00

commit f4817843e39ce78aace0195a57d4e8500a65a898 upstream.

There are two other drivers that bind to mrvl,mmp-uart and both of them
assume register shift of 2 bits. There are device trees that lack the
property and rely on that assumption.

If this driver wins the race to bind to those devices, it should behave
the same as the older deprecated driver.

Signed-off-by: Lubomir Rintel 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Make PCI class test non fatal

2019-01-30T08:35:46+00:00

As has been reported the National Instruments serial cards have broken
PCI class.

The commit 7d8905d06405

  ("serial: 8250_pci: Enable device after we check black list")

made the PCI class check mandatory for the case when device is listed in
a quirk list.

Make PCI class test non fatal to allow broken card be enumerated.

Fixes: 7d8905d06405 ("serial: 8250_pci: Enable device after we check black list")
Cc: stable 
Reported-by: Guan Yung Tseng 
Tested-by: Guan Yung Tseng 
Tested-by: KHUENY.Gerhard 
Signed-off-by: Andy Shevchenko 
Signed-off-by: Greg Kroah-Hartman

tty: serial: 8250_mtk: Fix potential NULL pointer dereference

2019-01-30T08:35:46+00:00

There is a potential NULL pointer dereference in case devm_kzalloc()
fails and returns NULL.

Fix this by adding a NULL check on data->dma

This bug was detected with the help of Coccinelle.

Fixes: 85b5c1dd0456 ("serial: 8250-mtk: add uart DMA support")
Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Greg Kroah-Hartman

serial: 8250: Fix serial8250 initialization crash

2019-01-18T12:03:47+00:00

The initialization code of interrupt backoff work might reference NULL
pointer and cause the following crash, if no port was found.

[   10.017727] CPU 0 Unable to handle kernel paging request at virtual address 000001b0, epc == 807088e0, ra == 8070863c
---- snip ----
[   11.704470] [<807088e0>] serial8250_register_8250_port+0x318/0x4ac
[   11.747251] [<80708d74>] serial8250_probe+0x148/0x1c0
[   11.789301] [<80728450>] platform_drv_probe+0x40/0x94
[   11.830515] [<807264f8>] really_probe+0xf8/0x318
[   11.870876] [<80726b7c>] __driver_attach+0x110/0x12c
[   11.910960] [<80724374>] bus_for_each_dev+0x78/0xcc
[   11.951134] [<80725958>] bus_add_driver+0x200/0x234
[   11.989756] [<807273d8>] driver_register+0x84/0x148
[   12.029832] [<80d72f84>] serial8250_init+0x138/0x198
[   12.070447] [<80100e6c>] do_one_initcall+0x5c/0x2a0
[   12.110104] [<80d3a208>] kernel_init_freeable+0x370/0x484
[   12.150722] [<80a49420>] kernel_init+0x10/0xf8
[   12.191517] [<8010756c>] ret_from_kernel_thread+0x14/0x1c

This patch makes sure the initialization code can be reached only if a port
is found.

Fixes: 6d7f677a2afa ("serial: 8250: Rate limit serial port rx interrupts during input overruns")
Signed-off-by: He Zhe 
Reviewed-by: Darwin Dingel 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'tty-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2018-12-29T04:33:54+00:00

Pull tty/serial driver updates from Greg KH:
 "Here is the large TTY/Serial driver set of patches for 4.21-rc1.

  A number of small serial driver changes along with some good tty core
  fixes for long-reported issues with locking. There is also a new
  console font added to the tree, for high-res screens, so that should
  be helpful for many.

  The last patch in the series is a revert of an older one in the tree,
  it came late but it resolves a reported issue that linux-next was
  having for some people.

  Full details are in the shortlog, and all of these, with the exception
  of the revert, have been in linux-next for a while with no reported
  issues"

* tag 'tty-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (85 commits)
  Revert "serial: 8250: Default SERIAL_OF_PLATFORM to SERIAL_8250"
  serial: sccnxp: Allow to use non-standard baud rates
  serial: sccnxp: Adds a delay between sequential read/write cycles
  tty: serial: qcom_geni_serial: Fix UART hang
  tty: serial: qcom_geni_serial: Fix wrap around of TX buffer
  serial: max310x: Fix tx_empty() callback
  dt-bindings: serial: sh-sci: Document r8a774c0 bindings
  dt-bindings: serial: sh-sci: Document r8a774a1 bindings
  Fonts: New Terminus large console font
  dt-bindings: serial: lpuart: add imx8qxp compatible string
  serial: uartps: Fix interrupt mask issue to handle the RX interrupts properly
  serial: uartps: Fix error path when alloc failed
  serial: uartps: Check if the device is a console
  serial: uartps: Add the device_init_wakeup
  tty: serial: samsung: Increase maximum baudrate
  tty: serial: samsung: Properly set flags in autoCTS mode
  tty: Use of_node_name_{eq,prefix} for node name comparisons
  tty/serial: do not free trasnmit buffer page under port lock
  serial: 8250: Rate limit serial port rx interrupts during input overruns
  dt-bindings: serial: 8250: Add rate limit for serial port input overruns
  ...

Revert "serial: 8250: Default SERIAL_OF_PLATFORM to SERIAL_8250"

2018-12-24T08:18:00+00:00

This reverts commit 6d11023c345e369bcb9d5a68b271764e362c1f6e.

It causes issues with Guenter's test systems and since there seems to
not be any agreement about _why_ this is a problem, but reverting it
fixes things, let's revert until the root cause is found.

Reported-by: Guenter Roeck 
Cc: Florian Fainelli 
Signed-off-by: Greg Kroah-Hartman

Revert "serial: 8250: Fix clearing FIFOs in RS485 mode again"

2018-12-17T15:18:29+00:00

Commit f6aa5beb45be ("serial: 8250: Fix clearing FIFOs in RS485 mode
again") makes a change to FIFO clearing code which its commit message
suggests was intended to be specific to use with RS485 mode, however:

 1) The change made does not just affect __do_stop_tx_rs485(), it also
    affects other uses of serial8250_clear_fifos() including paths for
    starting up, shutting down or auto-configuring a port regardless of
    whether it's an RS485 port or not.

 2) It makes the assumption that resetting the FIFOs is a no-op when
    FIFOs are disabled, and as such it checks for this case & explicitly
    avoids setting the FIFO reset bits when the FIFO enable bit is
    clear. A reading of the PC16550D manual would suggest that this is
    OK since the FIFO should automatically be reset if it is later
    enabled, but we support many 16550-compatible devices and have never
    required this auto-reset behaviour for at least the whole git era.
    Starting to rely on it now seems risky, offers no benefit, and
    indeed breaks at least the Ingenic JZ4780's UARTs which reads
    garbage when the RX FIFO is enabled if we don't explicitly reset it.

 3) By only resetting the FIFOs if they're enabled, the behaviour of
    serial8250_do_startup() during boot now depends on what the value of
    FCR is before the 8250 driver is probed. This in itself seems
    questionable and leaves us with FCR=0 & no FIFO reset if the UART
    was used by 8250_early, otherwise it depends upon what the
    bootloader left behind.

 4) Although the naming of serial8250_clear_fifos() may be unclear, it
    is clear that callers of it expect that it will disable FIFOs. Both
    serial8250_do_startup() & serial8250_do_shutdown() contain comments
    to that effect, and other callers explicitly re-enable the FIFOs
    after calling serial8250_clear_fifos(). The premise of that patch
    that disabling the FIFOs is incorrect therefore seems wrong.

For these reasons, this reverts commit f6aa5beb45be ("serial: 8250: Fix
clearing FIFOs in RS485 mode again").

Signed-off-by: Paul Burton 
Fixes: f6aa5beb45be ("serial: 8250: Fix clearing FIFOs in RS485 mode again").
Cc: Greg Kroah-Hartman 
Cc: Daniel Jedrychowski 
Cc: Marek Vasut 
Cc: linux-mips@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Cc: stable  # 4.10+
Signed-off-by: Greg Kroah-Hartman