Commit Graph

814 Commits

Author SHA1 Message Date
Linus Torvalds
31ef489a02 dmaengine updates for v5.1-rc1
- dmatest updates for modularizing common struct and code
  - remove SG support for VDMA xilinx IP and updates to driver
  - Update to dw driver to support Intel iDMA controllers
    multi-block support
  - tegra updates for proper reporting of residue
  - Add Snow Ridge ioatdma device id and support for IOATDMA v3.4
  - struct_size() usage and useless LIST_HEAD cleanups in subsystem.
  - qDMA controller driver for Layerscape SoCs
  - stm32-dma PM Runtime support
  - And usual updates to imx-sdma, sprd, Documentation, fsl-edma,
    bcm2835, qcom_hidma etc
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Merge tag 'dmaengine-5.1-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine updates from Vinod Koul:

 - dmatest updates for modularizing common struct and code

 - remove SG support for VDMA xilinx IP and updates to driver

 - Update to dw driver to support Intel iDMA controllers multi-block
   support

 - tegra updates for proper reporting of residue

 - Add Snow Ridge ioatdma device id and support for IOATDMA v3.4

 - struct_size() usage and useless LIST_HEAD cleanups in subsystem.

 - qDMA controller driver for Layerscape SoCs

 - stm32-dma PM Runtime support

 - And usual updates to imx-sdma, sprd, Documentation, fsl-edma,
   bcm2835, qcom_hidma etc

* tag 'dmaengine-5.1-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (81 commits)
  dmaengine: imx-sdma: fix consistent dma test failures
  dmaengine: imx-sdma: add a test for imx8mq multi sdma devices
  dmaengine: imx-sdma: add clock ratio 1:1 check
  dmaengine: dmatest: move test data alloc & free into functions
  dmaengine: dmatest: add short-hand `buf_size` var in dmatest_func()
  dmaengine: dmatest: wrap src & dst data into a struct
  dmaengine: ioatdma: support latency tolerance report (LTR) for v3.4
  dmaengine: ioatdma: add descriptor pre-fetch support for v3.4
  dmaengine: ioatdma: disable DCA enabling on IOATDMA v3.4
  dmaengine: ioatdma: Add Snow Ridge ioatdma device id
  dmaengine: sprd: Change channel id to slave id for DMA cell specifier
  dt-bindings: dmaengine: sprd: Change channel id to slave id for DMA cell specifier
  dmaengine: mv_xor: Use correct device for DMA API
  Documentation :dmaengine: clarify DMA desc. pointer after submission
  Documentation: dmaengine: fix dmatest.rst warning
  dmaengine: k3dma: Add support for dma-channel-mask
  dmaengine: k3dma: Delete axi_config
  dmaengine: k3dma: Upgrade k3dma driver to support hisi_asp_dma hardware
  Documentation: bindings: dma: Add binding for dma-channel-mask
  Documentation: bindings: k3dma: Extend the k3dma driver binding to support hisi-asp
  ...
2019-03-14 09:11:54 -07:00
Lubomir Rintel
f4817843e3 serial: 8250_of: assume reg-shift of 2 for mrvl,mmp-uart
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 <lkundrak@v3.sk>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-26 12:30:45 +01:00
Lubomir Rintel
fe9ed6d248 serial: 8250_pxa: honor the port number from devicetree
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 <lkundrak@v3.sk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-26 12:30:44 +01:00
Jay Dolan
78d3820b9b serial: 8250_pci: Have ACCES cards that use the four port Pericom PI7C9X7954 chip use the pci_pericom_setup()
The four port Pericom chips have the fourth port at the wrong address.
Make use of quirk to fix it.

Fixes: c8d192428f ("serial: 8250: added acces i/o products quad and octal serial cards")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jay Dolan <jay.dolan@accesio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-13 19:48:57 +01:00
Jay Dolan
b896b03bc7 serial: 8250_pci: Fix number of ports for ACCES serial cards
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: c8d192428f ("serial: 8250: added acces i/o products quad and octal serial cards")
Signed-off-by: Jay Dolan <jay.dolan@accesio.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-13 19:48:50 +01:00
Heikki Krogerus
54b2f300f3 serial: 8250_pci: Replace custom code with pci_match_id()
serial_pci_is_blacklisted() is very similar to pci_match_id() implementation.
Replace it with the latter.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-11 09:55:50 +01:00
Greg Kroah-Hartman
c744ca39f2 Merge 5.0-rc6 into tty-next
We need the tty fixes in here for other patches to be based on.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-11 09:26:45 +01:00
Andy Shevchenko
824d17c57b serial: 8250_pci: Make PCI class test non fatal
As has been reported the National Instruments serial cards have broken
PCI class.

The commit 7d8905d064

  ("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: 7d8905d064 ("serial: 8250_pci: Enable device after we check black list")
Cc: stable <stable@vger.kernel.org>
Reported-by: Guan Yung Tseng <guan.yung.tseng@ni.com>
Tested-by: Guan Yung Tseng <guan.yung.tseng@ni.com>
Tested-by: KHUENY.Gerhard <Gerhard.KHUENY@bachmann.info>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-30 09:35:46 +01:00
Gustavo A. R. Silva
1575c083a7 tty: serial: 8250_mtk: Fix potential NULL pointer dereference
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: 85b5c1dd04 ("serial: 8250-mtk: add uart DMA support")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-30 09:35:46 +01:00
Zhou Yanjie
8a417cdeb0 Serial: Ingenic: Add support for the X1000.
Add support for probing the 8250_ingenic driver on the
X1000 Soc from Ingenic.

Signed-off-by: Zhou Yanjie <zhouyanjie@zoho.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-30 09:31:30 +01:00
Linus Walleij
3a50365d8c serial: 8250: Add OF support for Xscale variant
This adds support for device tree probing for the Intel
Xscale 8250 variant needed to support device tree on
the Intel IXP4xx platforms.

Cc: devicetree@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-30 09:31:30 +01:00
Greg Kroah-Hartman
83b21ed0fc Merge 5.0-rc4 into tty-next
We need the tty and serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-28 08:22:00 +01:00
He Zhe
352c4cf40c serial: 8250: Fix serial8250 initialization crash
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: 6d7f677a2a ("serial: 8250: Rate limit serial port rx interrupts during input overruns")
Signed-off-by: He Zhe <zhe.he@windriver.com>
Reviewed-by: Darwin Dingel <darwin.dingel@alliedtelesis.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-18 13:03:47 +01:00
Vignesh R
7d470ebf58 serial: 8250_omap: Use clk_get_rate() to obtain fclk frequency
8250_omap driver uses clock-frequency DT property to obtain functional
clk frequency. This is not ideal as users need to calculate functional
clk frequency offline and populate it in DT.
Therefore add support to obtain functional clock frequency using clk
APIs when clock-frequency DT property is not defined.

Suggested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-18 11:23:00 +01:00
Vignesh R
d6ce4ec0b8 serial: 8250_omap: Drop check for of_node
8250_omap is DT only driver so dev->of_node always exists. Drop check
for existence of valid dev->of_node to simplify omap8250_probe().

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-18 11:23:00 +01:00
Andy Shevchenko
d7dba6be0f dmaengine: dw: Remove misleading is_private property
The commit a9ddb575d6

   ("dmaengine: dw_dmac: Enhance device tree support")

introduces is_private property in uncertain understanding what does it mean.

First of all, documentation defines DMA_PRIVATE capability as

Documentation/crypto/async-tx-api.txt:
  The DMA_PRIVATE capability flag is used to tag dma devices that should not be
  used by the general-purpose allocator. It can be set at initialization time
  if it is known that a channel will always be private. Alternatively,
  it is set when dma_request_channel() finds an unused "public" channel.

  A couple caveats to note when implementing a driver and consumer:
  1/ Once a channel has been privately allocated it will no longer be
     considered by the general-purpose allocator even after a call to
     dma_release_channel().
  2/ Since capabilities are specified at the device level a dma_device with
     multiple channels will either have all channels public, or all channels
     private.

Documentation/driver-api/dmaengine/provider.rst:
  - DMA_PRIVATE
    The devices only supports slave transfers, and as such isn't available
    for async transfers.

The capability had been introduced by the commit 59b5ec2144

  ("dmaengine: introduce dma_request_channel and private channels")

and some code didn't changed from that times ever.

Taking into consideration above and the fact that on all known platforms
Synopsys DesignWare DMA engine is attached to serve slave transfers,
the DMA_PRIVATE capability must be enabled for this device unconditionally.
Otherwise, as rightfully noticed in drivers/dma/at_xdmac.c:
  /*
   * Without DMA_PRIVATE the driver is not able to allocate more than
   * one channel, second allocation fails in private_candidate.
   */
because of of a caveats mentioned in above documentation excerpts.

So, remove conditional around DMA_PRIVATE followed by removal leftovers.

If someone wonders, DMA_PRIVATE can be not used if and only if the all channels
of the DMA controller are supposed to serve memory-to-memory like operations.
For example, EP93xx has two controllers, one of which can only perform
memory-to-memory transfers

Note, this change doesn't affect dmatest to be able to test such controllers.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> (maintainer:SERIAL DRIVERS)
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-01-07 17:57:13 +05:30
Linus Torvalds
117eda8f71 TTY/Serial driver patches for 4.21-rc1
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.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

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
  ...
2018-12-28 20:33:54 -08:00
Greg Kroah-Hartman
598134ffca Revert "serial: 8250: Default SERIAL_OF_PLATFORM to SERIAL_8250"
This reverts commit 6d11023c34.

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 <linux@roeck-us.net>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-24 09:18:00 +01:00
Paul Burton
3c9dc275db Revert "serial: 8250: Fix clearing FIFOs in RS485 mode again"
Commit f6aa5beb45 ("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 f6aa5beb45 ("serial: 8250: Fix
clearing FIFOs in RS485 mode again").

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: f6aa5beb45 ("serial: 8250: Fix clearing FIFOs in RS485 mode again").
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Daniel Jedrychowski <avistel@gmail.com>
Cc: Marek Vasut <marex@denx.de>
Cc: linux-mips@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Cc: stable <stable@vger.kernel.org> # 4.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-17 16:18:29 +01:00
Darwin Dingel
6d7f677a2a serial: 8250: Rate limit serial port rx interrupts during input overruns
When a serial port gets faulty or gets flooded with inputs, its interrupt
handler starts to work double time to get the characters to the workqueue
for the tty layer to handle them. When this busy time on the serial/tty
subsystem happens during boot, where it is also busy on the userspace
trying to initialise, some processes can continuously get preempted
and will be on hold until the interrupts subside.

The fix is to backoff on processing received characters for a specified
amount of time when an input overrun is seen (received a new character
before the previous one is processed). This only stops receive and will
continue to transmit characters to serial port. After the backoff period
is done, it receive will be re-enabled. This is optional and will only
be enabled by setting 'overrun-throttle-ms' in the dts.

Signed-off-by: Darwin Dingel <darwin.dingel@alliedtelesis.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-17 16:02:57 +01:00
Greg Kroah-Hartman
9c96f401e9 Merge 4.20-rc6 into tty-next
We want the TTY changes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-10 10:17:45 +01:00
Peter Shih
100bc3e2be tty: serial: 8250_mtk: always resume the device in probe.
serial8250_register_8250_port calls uart_config_port, which calls
config_port on the port before it tries to power on the port. So we need
the port to be on before calling serial8250_register_8250_port. Change
the code to always do a runtime resume in probe before registering port,
and always do a runtime suspend in remove.

This basically reverts the change in commit 68e5fc4a25 ("tty: serial:
8250_mtk: use pm_runtime callbacks for enabling"), but still use
pm_runtime callbacks.

Fixes: 68e5fc4a25 ("tty: serial: 8250_mtk: use pm_runtime callbacks for enabling")
Signed-off-by: Peter Shih <pihsun@chromium.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05 11:31:21 +01:00
Long Cheng
85b5c1dd04 serial: 8250-mtk: add uart DMA support
Modify uart register to support DMA function.

Signed-off-by: Long Cheng <long.cheng@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05 11:02:39 +01:00
Douglas Anderson
596f63da42 serial: 8250: Process sysrq at port unlock time
Let's take advantage of the new ("serial: core: Allow processing sysrq
at port unlock time") to handle sysrqs more cleanly.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-09 09:07:18 -08:00
Florian Fainelli
6d11023c34 serial: 8250: Default SERIAL_OF_PLATFORM to SERIAL_8250
It is way too easy to miss enabling SERIAL_OF_PLATFORM which would
result in the inability for the kernel to have a valid console device,
which can be seen with:

Warning: unable to open an initial console.

and then:

Run /init as init process
Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000100

Since SERIAL_OF_PLATFORM already depends on SERIAL_8250 && OF there
really is no drawback to defaulting this config to the value of
SERIAL_8250.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-09 09:07:17 -08:00
Greg Kroah-Hartman
4e1a606d55 Merge 4.19-rc7 into tty-next
We want the fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-08 15:43:12 +02:00
Guenter Roeck
beeeac43b6 Revert "serial: 8250_dw: Fix runtime PM handling"
This reverts commit d76c74387e.

While commit d76c74387e ("serial: 8250_dw: Fix runtime PM handling")
fixes runtime PM handling when using kgdb, it introduces a traceback for
everyone else.

BUG: sleeping function called from invalid context at
	/mnt/host/source/src/third_party/kernel/next/drivers/base/power/runtime.c:1034
in_atomic(): 1, irqs_disabled(): 1, pid: 1, name: swapper/0
7 locks held by swapper/0/1:
 #0: 000000005ec5bc72 (&dev->mutex){....}, at: __driver_attach+0xb5/0x12b
 #1: 000000005d5fa9e5 (&dev->mutex){....}, at: __device_attach+0x3e/0x15b
 #2: 0000000047e93286 (serial_mutex){+.+.}, at: serial8250_register_8250_port+0x51/0x8bb
 #3: 000000003b328f07 (port_mutex){+.+.}, at: uart_add_one_port+0xab/0x8b0
 #4: 00000000fa313d4d (&port->mutex){+.+.}, at: uart_add_one_port+0xcc/0x8b0
 #5: 00000000090983ca (console_lock){+.+.}, at: vprintk_emit+0xdb/0x217
 #6: 00000000c743e583 (console_owner){-...}, at: console_unlock+0x211/0x60f
irq event stamp: 735222
__down_trylock_console_sem+0x4a/0x84
console_unlock+0x338/0x60f
__do_softirq+0x4a4/0x50d
irq_exit+0x64/0xe2
CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5 #6
Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.286.0 03/15/2017
Call Trace:
 dump_stack+0x7d/0xbd
 ___might_sleep+0x238/0x259
 __pm_runtime_resume+0x4e/0xa4
 ? serial8250_rpm_get+0x2e/0x44
 serial8250_console_write+0x44/0x301
 ? lock_acquire+0x1b8/0x1fa
 console_unlock+0x577/0x60f
 vprintk_emit+0x1f0/0x217
 printk+0x52/0x6e
 register_console+0x43b/0x524
 uart_add_one_port+0x672/0x8b0
 ? set_io_from_upio+0x150/0x162
 serial8250_register_8250_port+0x825/0x8bb
 dw8250_probe+0x80c/0x8b0
 ? dw8250_serial_inq+0x8e/0x8e
 ? dw8250_check_lcr+0x108/0x108
 ? dw8250_runtime_resume+0x5b/0x5b
 ? dw8250_serial_outq+0xa1/0xa1
 ? dw8250_remove+0x115/0x115
 platform_drv_probe+0x76/0xc5
 really_probe+0x1f1/0x3ee
 ? driver_allows_async_probing+0x5d/0x5d
 driver_probe_device+0xd6/0x112
 ? driver_allows_async_probing+0x5d/0x5d
 bus_for_each_drv+0xbe/0xe5
 __device_attach+0xdd/0x15b
 bus_probe_device+0x5a/0x10b
 device_add+0x501/0x894
 ? _raw_write_unlock+0x27/0x3a
 platform_device_add+0x224/0x2b7
 mfd_add_device+0x718/0x75b
 ? __kmalloc+0x144/0x16a
 ? mfd_add_devices+0x38/0xdb
 mfd_add_devices+0x9b/0xdb
 intel_lpss_probe+0x7d4/0x8ee
 intel_lpss_pci_probe+0xac/0xd4
 pci_device_probe+0x101/0x18e
...

Revert the offending patch until a more comprehensive solution
is available.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Fixes: d76c74387e ("serial: 8250_dw: Fix runtime PM handling")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 14:35:10 -07:00
Dai Okamura
aad2d4952d serial: 8250_uniphier: add auto-flow-control support
Add selective auto-flow-control support for UniPhier serial driver.

Signed-off-by: Dai Okamura <okamura.dai@socionext.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:58 -07:00
Masahiro Yamada
aca70d19c8 serial: 8250_uniphier: flatten probe function
Currently, the DT-related settings are split out to
uniphier_of_serial_setup(), but it turned out to be not nice.
The next commit will add a DT property, but it will not fit in
the helper.  Merge the helper into the probe function.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:58 -07:00
Masahiro Yamada
2fd8e45418 serial: 8250_uniphier: remove unused "fifo-size" property
The FIFO size of the UART devices is 64 on almost all UniPhier SoCs
with the exception Pro4TV SoC (MN2WS0235), which used 128 FIFO size.
However, Pro4TV SoC was never upstreamed, and out of production.

So, this property has never been used in a useful way.
Let's remove old unused code.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:58 -07:00
Marek Vasut
f6aa5beb45 serial: 8250: Fix clearing FIFOs in RS485 mode again
The 8250 FIFOs indeed need to be cleared after stopping transmission in
RS485 mode without SER_RS485_RX_DURING_TX flag set. But there are two
problems with the approach taken by the previous patch from Fixes tag.

First, serial8250_clear_fifos() should clear fifos, but what it really
does is it enables the FIFOs unconditionally if present, clears them
and then sets the FCR register to zero, which effectively disables the
FIFOs. In case the FIFO is disabled, enabling it and clearing it makes
no sense and in fact can trigger misbehavior of the 8250 core. Moreover,
the FCR register may contain other FIFO configuration bits which may not
be writable unconditionally and writing them incorrectly can trigger
misbehavior of the 8250 core too. (ie. AM335x UART swallows the first
byte and retransmits the last byte twice because of this FCR write).

Second, serial8250_clear_and_reinit_fifos() completely reloads the FCR,
but what really has to happen at the end of the RS485 transmission is
clearing of the FIFOs and nothing else.

This patch repairs serial8250_clear_fifos() so that it really only
clears the FIFOs by operating on FCR[2:1] bits and leaves all the
other bits alone. It also undoes serial8250_clear_and_reinit_fifos()
from __do_stop_tx_rs485() as serial8250_clear_fifos() is sufficient.

Signed-off-by: Marek Vasut <marex@denx.de>
Fixes: 2bed8a8e70 ("Clearing FIFOs in RS485 emulation mode causes subsequent transmits to break")
Cc: Daniel Jedrychowski <avistel@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org> # let it bake a bit before merging
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:25 +02:00
John Garry
a27d938251 serial: 8250_of: Fix for lack of interrupt support
In commit c58caaab3b ("serial: 8250: of: Defer probe on missing IRQ"), a
check was added for the UART driver being probed prior to the parent IRQ
controller.

Unfortunately this breaks certain boards which have no interrupt support,
like Huawei D03.

Indeed, the 8250 DT bindings state that interrupts should be supported -
not must.

To fix, switch from irq_of_parse_and_map() to of_irq_get(), which
does relay whether the IRQ host controller domain is not ready, i.e.
defer probe, instead of assuming it.

Fixes: c58caaab3b ("serial: 8250: of: Defer probe on missing IRQ")
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Tested-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:25 +02:00
Lokesh Vutla
c886751465 serial: 8250_omap: Make 8250_omap driver driver depend on ARCH_K3
Allow 8250 omap serial driver to be used for K3 platforms.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:24 +02:00
Sebastian Andrzej Siewior
9d7c249a1e serial: 8250: drop the printk from serial8250_interrupt()
The printk() in serial8250_interrupt() was once hidden behind a debug
macro in commit f4f653e987 ("serial: 8250, disable "too much work"
messages") and reverted back in commit 12de375ec4 ("Revert "serial:
8250, disable "too much work" messages"").

This was introduced first in 0.99.13k with the "serial" driver itself
(and called pass_number with a limit of 64 and no print). In 1.1.13 it
was renamed to pass_counter and the printk was behind #if 0. In 1.1.94
the limit of 64 was increased to 256 and hidden behind
RS_ISR_PASS_LIMIT. With this change the #if 0 turned into #if 1. It
slowly become what we have today with a loop limit of 512.

Usually, that printk isn't hit. However on KVM with a busy UART and
overloaded host it might happen. It is also likely with threaded
interrupts and a task which preempts the interrupt handler.

If the UART has (legitimate) work to do and we break out of the loop,
nothing changes: the interrupt is most likely already pending in the
interrupt controller and we end up in the handler anyway. This printk is
hardly helping.

Older kernels also had a comment saying that a bad configuration might
lead to this but I don't see how that should happen because a wrongly
configured interrupt number would let the handler leave "early" with
IRQ_NONE and the spurious detected will handle that (weill since 2.6.11,
before that we had no spurious detector). In that case, we would never
loop that often here.

This loop looks like an optimisation in order to pull the bytes from the
FIFO which were received while we were already here instead of waiting
for the interrupt. This might have been a good idea while the CPUs were
slow and FIFOs small.
There are other serial driver in tree, like the amba-pl*, which also
have this kind of a loop but without the printk (and were based on this
driver).

Remove the printk which might trigger in otherwise valid situtations.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 16:07:23 +02:00
Linus Torvalds
d5acba26bf Char/Misc driver patches for 4.19-rc1
Here is the bit set of char/misc drivers for 4.19-rc1
 
 There is a lot here, much more than normal, seems like everyone is
 writing new driver subsystems these days...  Anyway, major things here
 are:
 	- new FSI driver subsystem, yet-another-powerpc low-level
 	  hardware bus
 	- gnss, finally an in-kernel GPS subsystem to try to tame all of
 	  the crazy out-of-tree drivers that have been floating around
 	  for years, combined with some really hacky userspace
 	  implementations.  This is only for GNSS receivers, but you
 	  have to start somewhere, and this is great to see.
 Other than that, there are new slimbus drivers, new coresight drivers,
 new fpga drivers, and loads of DT bindings for all of these and existing
 drivers.
 
 Full details of everything is 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>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCW3g7ew8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ykfBgCeOG0RkSI92XVZe0hs/QYFW9kk8JYAnRBf3Qpm
 cvW7a+McOoKz/MGmEKsi
 =TNfn
 -----END PGP SIGNATURE-----

Merge tag 'char-misc-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the bit set of char/misc drivers for 4.19-rc1

  There is a lot here, much more than normal, seems like everyone is
  writing new driver subsystems these days... Anyway, major things here
  are:

   - new FSI driver subsystem, yet-another-powerpc low-level hardware
     bus

   - gnss, finally an in-kernel GPS subsystem to try to tame all of the
     crazy out-of-tree drivers that have been floating around for years,
     combined with some really hacky userspace implementations. This is
     only for GNSS receivers, but you have to start somewhere, and this
     is great to see.

  Other than that, there are new slimbus drivers, new coresight drivers,
  new fpga drivers, and loads of DT bindings for all of these and
  existing drivers.

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

* tag 'char-misc-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (255 commits)
  android: binder: Rate-limit debug and userspace triggered err msgs
  fsi: sbefifo: Bump max command length
  fsi: scom: Fix NULL dereference
  misc: mic: SCIF Fix scif_get_new_port() error handling
  misc: cxl: changed asterisk position
  genwqe: card_base: Use true and false for boolean values
  misc: eeprom: assignment outside the if statement
  uio: potential double frees if __uio_register_device() fails
  eeprom: idt_89hpesx: clean up an error pointer vs NULL inconsistency
  misc: ti-st: Fix memory leak in the error path of probe()
  android: binder: Show extra_buffers_size in trace
  firmware: vpd: Fix section enabled flag on vpd_section_destroy
  platform: goldfish: Retire pdev_bus
  goldfish: Use dedicated macros instead of manual bit shifting
  goldfish: Add missing includes to goldfish.h
  mux: adgs1408: new driver for Analog Devices ADGS1408/1409 mux
  dt-bindings: mux: add adi,adgs1408
  Drivers: hv: vmbus: Cleanup synic memory free path
  Drivers: hv: vmbus: Remove use of slow_virt_to_phys()
  Drivers: hv: vmbus: Reset the channel callback in vmbus_onoffer_rescind()
  ...
2018-08-18 11:04:51 -07:00
Mark
47ac76662c tty: serial: 8250: Revert NXP SC16C2552 workaround
Revert commit ecb988a3b7: tty: serial:
8250: 8250_core: NXP SC16C2552 workaround

The above commit causes userland application to no longer write
correctly its first write to a dumb terminal connected to /dev/ttyS0.
This commit seems to be the culprit. It's as though the TX FIFO is being
reset during that write. What should be displayed is:

PSW 80000000 INST 00000000                           HALT
//

What is displayed is some variation of:

T 00000000           HAL//

Reverting this commit via this patch fixes my problem.

Signed-off-by: Mark Hounschell <dmarkh@cfl.rr.com>
Fixes: ecb988a3b7 ("tty: serial: 8250: 8250_core: NXP SC16C2552 workaround")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-12 18:53:30 +02:00
Aaron Sierra
60ab0fafc4 serial: 8250_exar: Read INT0 from slave device, too
The sleep wake-up refactoring that I introduced in

  commit c7e1b40590 ("tty: serial: exar: Relocate sleep wake-up handling")

did not account for devices with a slave device on the expansion port.
This patch pokes the INT0 register in the slave device, if present, in
order to ensure that MSI interrupts don't get permanently "stuck"
because of a sleep wake-up interrupt as described here:

  commit 2c0ac5b48a ("serial: exar: Fix stuck MSIs")

This also converts an ioread8() to readb() in order to provide visual
consistency with the MMIO-only accessors used elsewhere in the driver.

Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Aaron Sierra <asierra@xes-inc.com>
Fixes: c7e1b40590 ("tty: serial: exar: Relocate sleep wake-up handling")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-02 10:11:35 +02:00
Srinath Mannam
784c29eda5 serial: 8250_dw: Add ACPI support for uart on Broadcom SoC
Add ACPI identifier HID for UART DW 8250 on Broadcom SoCs
to match the HID passed through ACPI tables to enable
UART controller.

Signed-off-by: Srinath Mannam <srinath.mannam@broadcom.com>
Reviewed-by: Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>
Tested-by: Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-02 10:11:32 +02:00
Chen Hu
dfcab6ba57 serial: 8250_dw: always set baud rate in dw8250_set_termios
dw8250_set_termios() doesn't set baud rate if the arg "old ktermios" is
NULL. This happens during resume.
Call Trace:
...
[   54.928108] dw8250_set_termios+0x162/0x170
[   54.928114] serial8250_set_termios+0x17/0x20
[   54.928117] uart_change_speed+0x64/0x160
[   54.928119] uart_resume_port
...

So the baud rate is not restored after S3 and breaks the apps who use
UART, for example, console and bluetooth etc.

We address this issue by setting the baud rate irrespective of arg
"old", just like the drivers for other 8250 IPs. This is tested with
Intel Broxton platform.

Signed-off-by: Chen Hu <hu1.chen@intel.com>
Fixes: 4e26b134bd ("serial: 8250_dw: clock rate handling for all ACPI platforms")
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-02 10:11:32 +02:00
Andy Shevchenko
286d9b8c7d serial: 8250: Use cached port name directly in messages
Since we have port name stored in struct uart_port, we better to use
that one instead of open coding.

This will make it one place source for easier maintenance or
modifications.

While here, replace printk_ratelimited(KERN_INFO ) by pr_info_ratelimited().
It seems last printk() call in 8250_port.c.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-25 12:51:23 +02:00
Andy Shevchenko
b340cbbea5 serial: 8250_exar: Drop unused variable in pci_xr17v35x_setup()
After removal has_slave use the variable board becomes unused.
Remove it to avoid a warning:

drivers/tty/serial/8250/8250_exar.c: In function 'pci_xr17v35x_setup':
drivers/tty/serial/8250/8250_exar.c:380:31: warning: unused variable 'board' [-Wunused-variable]
  const struct exar8250_board *board = priv->board;
                               ^~~~~

Fixes: 328c11f24b ("serial: 8250_exar: Remove useless has_slave member")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 14:15:49 +02:00
Andy Shevchenko
26f22d5748 serial: 8250_exar: Describe all members in struct exar8250_board
Describe all memebers in struct exar8250_board, otherwise we get a warning:

drivers/tty/serial/8250/8250_exar.c:122: warning: Function parameter or member 'has_slave' not described in 'exar8250_board'
drivers/tty/serial/8250/8250_exar.c:122: warning: Function parameter or member 'setup' not described in 'exar8250_board'
drivers/tty/serial/8250/8250_exar.c:122: warning: Function parameter or member 'exit' not described in 'exar8250_board'

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-21 08:40:45 +02:00
Andy Shevchenko
328c11f24b serial: 8250_exar: Remove useless has_slave member
Exar UARTs by default supports only up to 8 channels,
all above go as extension. Thus, there is no need to have
an additional property to distinguish them from first ones.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-21 08:40:45 +02:00
Phil Edworthy
2ff5fa7f74 serial: 8250_dw: Add compatible string for Renesas RZ/N1 UART
The Renesas RZ/N1 UART is based on the Synopsys DW UART, but has additional
registers for DMA. This patch does not address the changes required for DMA
support, it simply adds the compatible string.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-21 08:39:25 +02:00
Alexander Sverdlin
c58caaab3b serial: 8250: of: Defer probe on missing IRQ
If the IRQ controller is not yet probed do not proceed with irq=0,
try to defer the probe.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-16 11:56:22 +02:00
Alexander Sverdlin
b29330d829 serial: 8250: of: Correct of_platform_serial_setup() error handling
Don't dispose IRQ mapping before it has been created.

Fixes: aa9594740 ("serial: 8250_of: Add IO space support")
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-16 11:56:22 +02:00
Greg Kroah-Hartman
83cf9cd6d5 Merge 4.18-rc5 into char-misc-next
We want the char-misc fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-16 09:04:54 +02:00
Jisheng Zhang
701c5e73b2 serial: 8250_dw: add fractional divisor support
For Synopsys DesignWare 8250 uart which version >= 4.00a, there's a
valid divisor latch fraction register. The fractional divisor width is
4bits ~ 6bits.

Now the preparation is done, it's easy to add the feature support.
This patch firstly tries to get the fractional divisor width during
probe, then setups dw specific get_divisor() and set_divisor() hook.

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-12 17:07:26 +02:00
Jisheng Zhang
6226e5f31a serial: 8250: export serial8250_do_set_divisor()
Some drivers could call serial8250_do_set_divisor() to complete its
own set_divisor routine. Export this symbol for code reusing.

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-12 17:07:26 +02:00
Jisheng Zhang
0238d2b4a4 serial: 8250: introduce get_divisor() and set_divisor() hook
Add these two hooks so that they can be overridden with driver specific
implementations.

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-12 17:07:26 +02:00