Commit Graph

4031 Commits

Author SHA1 Message Date
Serge Semin
9c12d739d6 tty: max310x: Split uart characters insertion loop
Batch read mode doesn't check any conditions or flags except the Rx
overflow one. But it may only happen after the last character is pushed
into the RHR register. In this case we shouldn't push all the read
characters with overrun flag set, but only the last one caused the
FIFO overflow. This commit splits the characters retrieval loop into
two parts. First one is ordinary intsert-chars procedure without taking
the overrun status into account. Second part inserts the last character
checking whether the overrun happened and pushing a '\0' character with
TTY_OVERRUN flag to a flip-buffer.

If we left the loop the way it was the '\0' character would be inserted
after each character retrieved at the overrun occasion.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 12:15:54 +02:00
Serge Semin
2b9e6f0a40 tty: max310x: Optionally enable rs485 on startup
UART port might be pre-configured with rs485 enabled flag at the
time of the port starting up process. In this case we need to
have the hardware rs485-related registers initialized in accordance
with the rs485 flags and settings provided by the configs descriptor.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 12:15:53 +02:00
Serge Semin
68f22c0c99 tty: max310x: Add rx-during-tx rs485 flag support
The driver currently sets the echo suppression bit by default when rs485
is enabled. Naturally it disables any data retrieval in rs485 mode while
RTSn is pushed up. The receiver gate (RX_) can be enabled just by clearing
(or not setting) the EchoSuprs bit of mode2 register. So by setting or
clearing the bit we implement the SER_RS485_RX_DURING_TX rs485 flag
support.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 12:15:53 +02:00
Serge Semin
35240ba26a tty: max310x: Fix invalid baudrate divisors calculator
Current calculator doesn't do it' job quite correct. First of all the
max310x baud-rates generator supports the divisor being less than 16.
In this case the x2/x4 modes can be used to double or quadruple
the reference frequency. But the current baud-rate setter function
just filters all these modes out by the first condition and setups
these modes only if there is a clocks-baud division remainder. The former
doesn't seem right at all, since enabling the x2/x4 modes causes the line
noise tolerance reduction and should be only used as a last resort to
enable a requested too high baud-rate.

Finally the fraction is supposed to be calculated from D = Fref/(c*baud)
formulae, but not from D % 16, which causes the precision loss. So to speak
the current baud-rate calculator code works well only if the baud perfectly
fits to the uart reference input frequency.

Lets fix the calculator by implementing the algo fully compliant with
the fractional baud-rate generator described in the datasheet:
D = Fref / (c*baud), where c={16,8,4} is the x1/x2/x4 rate mode
respectively, Fref - reference input frequency. The divisor fraction is
calculated from the same formulae, but making sure it is found with a
resolution of 0.0625 (four bits).

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 12:15:53 +02:00
Serge Semin
b7382c73b2 tty: max310x: Don't pass stacked buffers to SPI
SPI transfer tx/rx buffers must be DMA-safe and the structure
documentation clearly states this. Data declared on the system stack isn't
DMA-safe [1]. Instead at least kernel memory should be used for the
buffers. In order to fix this here we can create the buffers at the device
probing stage and use them without any synchronization, since batch
read/write methods are called from non-reentrant contexts - either from
rx-event IRQ threaded handler or from the tx workqueue item.

[1] Documentation/DMA-API-HOWTO.txt

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 12:15:53 +02:00
Serge Semin
1b5d239af3 tty: max310x: Introduce max310x_one port macro-wrapper
uart_port structure instance is embedded into the max310x_one
super-structure, which is accessed by some of the uart-port callback
methods. In order to improve the callback's code readability lets
define the to_max310x_port() wrapper which just translates the passed
uart_port pointer to the max310x_one one. It is also going to be
handy in future commits.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 12:15:53 +02:00
Serge Semin
2987590b78 tty: max310x: Simplify tx-work item code
Since cmwq introduction in the kernel, workqueues've been turned into
non-reentrant execution contexts [1]. It means any work item is
guaranteed to be executed by at most one worker system-wide at any
given time. Since tx-handler max310x_handle_tx() is called by a
single work item we don't need it to be self-protected by the mutex.
We also don't need to check the tx work item pending state before
scheduling it (which in the first place was racy btw), since cmwq will
make sure to reschedule the item if it wasn't pending at the moment of
schedule_work() call.

[1] Documentation/core-api/workqueue.rst

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 12:15:53 +02:00
Doug Berger
9f20e8843e tty: amba-pl011: allow shared interrupt
The PL011 register space includes all necessary status bits to
determine whether a device instance requires handling in response
to an interrupt. Therefore, multiple instances of the device could
be serviced by a single shared interrupt, which is the case on BCM7211.

Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 12:12:03 +02:00
Hao Lee
dfaffb9dca tty: serial: 8250: Fix type field in format string
The dev_dbg statement should print the value of uart.port.mapbase instead
of its address. Besides that, uart.port.irq and uart.port.iotype are all
unsigned types, so using %u is more appropriate.

Signed-off-by: Hao Lee <haolee.swjtu@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 12:12:03 +02:00
Andy Shevchenko
525667c025 serial: 8250_of: Use of_device_get_match_data()
Use of_device_get_match_data() to simplify the code a bit.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 12:12:02 +02:00
Linus Torvalds
055128ee00 dmaengine updates for v5.2-rc1
- Updates to stm32 dma residue calculations
  - Interleave dma capability to axi-dmac and
    support for ZynqMP arch
  - Rework of channel assignment for rcar dma
  - Debugfs for pl330 driver
  - Support for Tegra186/Tegra194, refactoring for new chips
    and support for pause/resume
  - Updates to axi-dmac, bcm2835, fsl-edma, idma64, imx-sdma,
    rcar-dmac, stm32-dma etc
  - dev_get_drvdata() updates on few drivers
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Merge tag 'dmaengine-5.2-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine updates from Vinod Koul:

 - Updates to stm32 dma residue calculations

 - Interleave dma capability to axi-dmac and support for ZynqMP arch

 - Rework of channel assignment for rcar dma

 - Debugfs for pl330 driver

 - Support for Tegra186/Tegra194, refactoring for new chips and support
   for pause/resume

 - Updates to axi-dmac, bcm2835, fsl-edma, idma64, imx-sdma, rcar-dmac,
   stm32-dma etc

 - dev_get_drvdata() updates on few drivers

* tag 'dmaengine-5.2-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (34 commits)
  dmaengine: tegra210-adma: restore channel status
  dmaengine: tegra210-dma: free dma controller in remove()
  dmaengine: tegra210-adma: add pause/resume support
  dmaengine: tegra210-adma: add support for Tegra186/Tegra194
  Documentation: DT: Add compatibility binding for Tegra186
  dmaengine: tegra210-adma: prepare for supporting newer Tegra chips
  dmaengine: at_xdmac: remove a stray bottom half unlock
  dmaengine: fsl-edma: Adjust indentation
  dmaengine: fsl-edma: Fix typo in Vybrid name
  dmaengine: stm32-dma: fix residue calculation in stm32-dma
  dmaengine: nbpfaxi: Use dev_get_drvdata()
  dmaengine: bcm-sba-raid: Use dev_get_drvdata()
  dmaengine: stm32-dma: Fix unsigned variable compared with zero
  dmaengine: stm32-dma: use platform_get_irq()
  dmaengine: rcar-dmac: Update copyright information
  dmaengine: imx-sdma: Only check ratio on parts that support 1:1
  dmaengine: xgene-dma: fix spelling mistake "descripto" -> "descriptor"
  dmaengine: idma64: Move driver name to the header
  dmaengine: bcm2835: Drop duplicate capability setting.
  dmaengine: pl330: _stop: clear interrupt status
  ...
2019-05-09 08:51:45 -07:00
Linus Torvalds
b3a5e648f5 TTY/Serial patches for 5.2-rc1
Here is the "big" set of tty/serial driver patches for 5.2-rc1.
 
 It's really pretty small, not much happening in this portion of the
 kernel at the moment.  When the "highlight" is the movement of the
 documentation from .txt to .rst files, it's a good merge window.
 
 There's a number of small fixes and updates over the various serial
 drivers, and a new "tty null" driver for those embedded systems that
 like to make things even smaller and not break things.
 
 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-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here is the "big" set of tty/serial driver patches for 5.2-rc1.

  It's really pretty small, not much happening in this portion of the
  kernel at the moment. When the "highlight" is the movement of the
  documentation from .txt to .rst files, it's a good merge window.

  There's a number of small fixes and updates over the various serial
  drivers, and a new "tty null" driver for those embedded systems that
  like to make things even smaller and not break things.

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

* tag 'tty-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (45 commits)
  tty: serial: add driver for the SiFive UART
  dt-bindings: serial: add documentation for the SiFive UART driver
  serial: uartps: Add support for cts-override
  dt-bindings: xilinx-uartps: Add support for cts-override
  serial: milbeaut_usio: Fix error handling in probe and remove
  tty: rocket: deprecate the rp_ioctl
  tty: rocket: Remove RCPK_GET_STRUCT ioctl
  tty: update obsolete termios comment
  tty: serial_core: fix error code returned by uart_register_driver()
  serial: 8250-mtk: modify baudrate setting
  serial: 8250-mtk: add follow control
  docs: serial: convert docs to ReST and rename to *.rst
  serial: 8250_exar: Adjust IOT2000 matching
  TTY: serial_core, add ->install
  serial: Fix using plain integer instead of Null pointer
  tty:serial_core: Spelling mistake
  tty: Add NULL TTY driver
  tty: vt: keyboard: Allow Unicode compose base char
  Revert "tty: fix NULL pointer issue when tty_port ops is not set"
  serial: Add Milbeaut serial control
  ...
2019-05-08 10:07:28 -07:00
Linus Torvalds
dd4e5d6106 Remove Mysterious Macro Intended to Obscure Weird Behaviours (mmiowb())
Remove mmiowb() from the kernel memory barrier API and instead, for
 architectures that need it, hide the barrier inside spin_unlock() when
 MMIO has been performed inside the critical section.
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Merge tag 'arm64-mmiowb' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull mmiowb removal from Will Deacon:
 "Remove Mysterious Macro Intended to Obscure Weird Behaviours (mmiowb())

  Remove mmiowb() from the kernel memory barrier API and instead, for
  architectures that need it, hide the barrier inside spin_unlock() when
  MMIO has been performed inside the critical section.

  The only relatively recent changes have been addressing review
  comments on the documentation, which is in a much better shape thanks
  to the efforts of Ben and Ingo.

  I was initially planning to split this into two pull requests so that
  you could run the coccinelle script yourself, however it's been plain
  sailing in linux-next so I've just included the whole lot here to keep
  things simple"

* tag 'arm64-mmiowb' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (23 commits)
  docs/memory-barriers.txt: Update I/O section to be clearer about CPU vs thread
  docs/memory-barriers.txt: Fix style, spacing and grammar in I/O section
  arch: Remove dummy mmiowb() definitions from arch code
  net/ethernet/silan/sc92031: Remove stale comment about mmiowb()
  i40iw: Redefine i40iw_mmiowb() to do nothing
  scsi/qla1280: Remove stale comment about mmiowb()
  drivers: Remove explicit invocations of mmiowb()
  drivers: Remove useless trailing comments from mmiowb() invocations
  Documentation: Kill all references to mmiowb()
  riscv/mmiowb: Hook up mmwiob() implementation to asm-generic code
  powerpc/mmiowb: Hook up mmwiob() implementation to asm-generic code
  ia64/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
  mips/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
  sh/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
  m68k/io: Remove useless definition of mmiowb()
  nds32/io: Remove useless definition of mmiowb()
  x86/io: Remove useless definition of mmiowb()
  arm64/io: Remove useless definition of mmiowb()
  ARM/io: Remove useless definition of mmiowb()
  mmiowb: Hook up mmiowb helpers to spinlocks and generic I/O accessors
  ...
2019-05-06 16:57:52 -07:00
Paul Walmsley
45c054d081 tty: serial: add driver for the SiFive UART
Add a serial driver for the SiFive UART, found on SiFive FU540 devices
(among others).

The underlying serial IP block is relatively basic, and currently does
not support serial break detection.  Further information on the IP
block can be found in the documentation and Chisel sources:

    https://static.dev.sifive.com/FU540-C000-v1.0.pdf

    https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart

This driver was written in collaboration with Wesley Terpstra
<wesley@sifive.com>.

Tested on a SiFive HiFive Unleashed A00 board, using BBL and the open-
source FSBL (using a DT file based on what's targeted for mainline).

This revision incorporates changes based on comments by Julia Lawall
<julia.lawall@lip6.fr>, Emil Renner Berthing <kernel@esmil.dk>, and
Andreas Schwab <schwab@suse.de>.  Thanks also to Andreas for testing
the driver with his userspace and reporting a bug with the
set_termios implementation.

Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Wesley Terpstra <wesley@sifive.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Emil Renner Berthing <kernel@esmil.dk>
Cc: Andreas Schwab <schwab@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-29 16:30:59 +02:00
Shubhrajyoti Datta
1863178b20 serial: uartps: Add support for cts-override
Having flow is configurable. Add support for the same by
checking for cts-override.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-29 16:20:24 +02:00
Wei Yongjun
74cdf8cec7 serial: milbeaut_usio: Fix error handling in probe and remove
devm_clk_get() is used so there is no reason to explicitly call
clk_put() in probe or remove functions. Also remove duplicate assign
for port->membase.

Fixes: ba44dc0430 ("serial: Add Milbeaut serial control")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Tested-by: Sugaya Taichi <sugaya.taichi@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-29 16:20:24 +02:00
Sergey Organov
050dfc09f8 tty: serial_core: fix error code returned by uart_register_driver()
uart_register_driver() returned -ENOMEM on any error, even when
tty_register_driver() call returned another one, such as -EBUSY.

Signed-off-by: Sergey Organov <sorganov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 11:39:51 +02:00
Long Cheng
bdbd0a7f8f serial: 8250-mtk: modify baudrate setting
In termios function, add Fractional divider to adjust baudrate.

Signed-off-by: Long Cheng <long.cheng@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 11:37:42 +02:00
Long Cheng
8ceeb47098 serial: 8250-mtk: add follow control
Add SW and HW follow control function.

Signed-off-by: Long Cheng <long.cheng@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 11:37:42 +02:00
Mauro Carvalho Chehab
f137401780 docs: serial: convert docs to ReST and rename to *.rst
The converted files are focused at the Kernel internal API,
so, this is a good candidate for the kernel API set of books.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 11:37:42 +02:00
Su Bao Cheng
3e51ceea10 serial: 8250_exar: Adjust IOT2000 matching
Since there are more IOT2040 variants with identical hardware but
different asset tags, the asset tag matching should be adjusted to
support them.

As only the IOT2040 variants have the Exar chip on board, matching on
their board name is enough. In the future there will be no other devices
with the "SIMATIC IOT2000" DMI board name but different hardware.

Signed-off-by: Su Bao Cheng <baocheng.su@siemens.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 11:37:41 +02:00
Jiri Slaby
4cdd17ba1d TTY: serial_core, add ->install
We need to compute the uart state only on the first open. This is
usually what is done in the ->install hook. serial_core used to do this
in ->open on every open. So move it to ->install.

As a side effect, it ensures the state is set properly in the window
after tty_init_dev is called, but before uart_open. This fixes a bunch
of races between tty_open and flush_to_ldisc we were dealing with
recently.

One of such bugs was attempted to fix in commit fedb576064 (serial:
fix race between flush_to_ldisc and tty_open), but it only took care of
a couple of functions (uart_start and uart_unthrottle).  I was able to
reproduce the crash on a SLE system, but in uart_write_room which is
also called from flush_to_ldisc via process_echoes. I was *unable* to
reproduce the bug locally. It is due to having this patch in my queue
since 2012!

 general protection fault: 0000 [#1] SMP KASAN PTI
 CPU: 1 PID: 5 Comm: kworker/u4:0 Tainted: G             L 4.12.14-396-default #1 SLE15-SP1 (unreleased)
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c89-prebuilt.qemu.org 04/01/2014
 Workqueue: events_unbound flush_to_ldisc
 task: ffff8800427d8040 task.stack: ffff8800427f0000
 RIP: 0010:uart_write_room+0xc4/0x590
 RSP: 0018:ffff8800427f7088 EFLAGS: 00010202
 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 000000000000002f RSI: 00000000000000ee RDI: ffff88003888bd90
 RBP: ffffffffb9545850 R08: 0000000000000001 R09: 0000000000000400
 R10: ffff8800427d825c R11: 000000000000006e R12: 1ffff100084fee12
 R13: ffffc900004c5000 R14: ffff88003888bb28 R15: 0000000000000178
 FS:  0000000000000000(0000) GS:ffff880043300000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000561da0794148 CR3: 000000000ebf4000 CR4: 00000000000006e0
 Call Trace:
  tty_write_room+0x6d/0xc0
  __process_echoes+0x55/0x870
  n_tty_receive_buf_common+0x105e/0x26d0
  tty_ldisc_receive_buf+0xb7/0x1c0
  tty_port_default_receive_buf+0x107/0x180
  flush_to_ldisc+0x35d/0x5c0
...

0 in rbx means tty->driver_data is NULL in uart_write_room. 0x178 is
tried to be dereferenced (0x178 >> 3 is 0x2f in rdx) at
uart_write_room+0xc4. 0x178 is exactly (struct uart_state *)NULL->refcount
used in uart_port_lock from uart_write_room.

So revert the upstream commit here as my local patch should fix the
whole family.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Li RongQing <lirongqing@baidu.com>
Cc: Wang Li <wangli39@baidu.com>
Cc: Zhang Yu <zhangyu31@baidu.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 11:37:41 +02:00
Sugaya Taichi
6bc3703dcf serial: Fix using plain integer instead of Null pointer
Fix build warning that using plain integer as Null pointer.
This is reported by kbuild test robot.

Fixes: ba44dc0430 ("serial: Add Milbeaut serial control")
Signed-off-by: Sugaya Taichi <sugaya.taichi@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 11:37:41 +02:00
Greg Kroah-Hartman
3b8a1f45e1 Merge 5.1-rc6 into tty-next
We want the serial/tty fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-21 23:20:08 +02:00
Guoqing Jiang
c53051128b sc16is7xx: put err_spi and err_i2c into correct #ifdef
err_spi is only called within SERIAL_SC16IS7XX_SPI
while err_i2c is called inside SERIAL_SC16IS7XX_I2C.
So we need to put err_spi and err_i2c into each #ifdef
accordingly.

This change fixes ("sc16is7xx: move label 'err_spi'
to correct section").

Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-19 14:09:23 +02:00
Hariprasad Kelam
c7a6b9e4df tty:serial_core: Spelling mistake
fix spelling mistake "overriden" -> "overridden"

This fix resolves warning reported by checkpatch tool.

Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16 15:25:40 +02:00
Guoqing Jiang
e00164a0f0 sc16is7xx: move label 'err_spi' to correct section
err_spi is used when SERIAL_SC16IS7XX_SPI is enabled, so make
the label only available under SERIAL_SC16IS7XX_SPI option.
Otherwise, the below warning appears.

drivers/tty/serial/sc16is7xx.c:1523:1: warning: label ‘err_spi’ defined but not used [-Wunused-label]
 err_spi:
  ^~~~~~~

Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Fixes: ac0cdb3d99 ("sc16is7xx: missing unregister/delete driver on error in sc16is7xx_init()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16 15:24:38 +02:00
Geert Uytterhoeven
6b87784b53 serial: sh-sci: Fix HSCIF RX sampling point adjustment
The calculation of the sampling point has min() and max() exchanged.
Fix this by using the clamp() helper instead.

Fixes: 63ba1e00f1 ("serial: sh-sci: Support for HSCIF RX sampling point adjustment")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Dirk Behme <dirk.behme@de.bosch.com>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16 15:24:38 +02:00
Geert Uytterhoeven
ace965696d serial: sh-sci: Fix HSCIF RX sampling point calculation
There are several issues with the formula used for calculating the
deviation from the intended rate:
  1. While min_err and last_stop are signed, srr and baud are unsigned.
     Hence the signed values are promoted to unsigned, which will lead
     to a bogus value of deviation if min_err is negative,
  2. Srr is the register field value, which is one less than the actual
     sampling rate factor,
  3. The divisions do not use rounding.

Fix this by casting unsigned variables to int, adding one to srr, and
using a single DIV_ROUND_CLOSEST().

Fixes: 63ba1e00f1 ("serial: sh-sci: Support for HSCIF RX sampling point adjustment")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16 15:24:38 +02:00
Sugaya Taichi
ba44dc0430 serial: Add Milbeaut serial control
Add Milbeaut serial control including earlycon and console.

Signed-off-by: Sugaya Taichi <sugaya.taichi@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16 15:21:34 +02:00
Bartlomiej Zolnierkiewicz
f692f7766f tty: remove redundant 'default n' from Kconfig-s
'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.

Also since commit f467c5640c ("kconfig: only write '# CONFIG_FOO
is not set' for visible symbols") the Kconfig behavior is the same
regardless of 'default n' being present or not:

    ...
    One side effect of (and the main motivation for) this change is making
    the following two definitions behave exactly the same:

        config FOO
                bool

        config FOO
                bool
                default n

    With this change, neither of these will generate a
    '# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
    That might make it clearer to people that a bare 'default n' is
    redundant.
    ...

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16 15:21:33 +02:00
YueHaibing
7a7457ba40 serial: sprd: Fix a copy-paste err in sprd_request_dma()
when dma_request_chan rx_dma fails, dev_err log should print rx_dma
err log.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Reviewed-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16 15:21:33 +02:00
Will Deacon
fb24ea52f7 drivers: Remove explicit invocations of mmiowb()
mmiowb() is now implied by spin_unlock() on architectures that require
it, so there is no reason to call it from driver code. This patch was
generated using coccinelle:

	@mmiowb@
	@@
	- mmiowb();

and invoked as:

$ for d in drivers include/linux/qed sound; do \
spatch --include-headers --sp-file mmiowb.cocci --dir $d --in-place; done

NOTE: mmiowb() has only ever guaranteed ordering in conjunction with
spin_unlock(). However, pairing each mmiowb() removal in this patch with
the corresponding call to spin_unlock() is not at all trivial, so there
is a small chance that this change may regress any drivers incorrectly
relying on mmiowb() to order MMIO writes between CPUs using lock-free
synchronisation. If you've ended up bisecting to this commit, you can
reintroduce the mmiowb() calls using wmb() instead, which should restore
the old behaviour on all architectures other than some esoteric ia64
systems.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-08 12:01:02 +01:00
Greg Kroah-Hartman
f16aa97d3f tty: fix up a few remaining files without SPDX identifiers
There were a few straggling files under drivers/tty/ that did not have
any SPDX identifier either because they entered the tree recently, or
they somehow missed the mass-tagging of commit b24413180f ("License
cleanup: add SPDX GPL-2.0 license identifier to files with no license")

This commit follows the same rule as b24413180f ("License cleanup: add
SPDX GPL-2.0 license identifier to files with no license") where files
without any specified license in them fall under GPL-2.0 as the correct
license for the individual file.  Add that identifier to these remaining
files so that we don't have to guess at the license of them in the
future.

Cc: Jiri Slaby <jslaby@suse.com>
Cc: "David S. Miller" <davem@davemloft.net>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-04 18:48:43 +02:00
Greg Kroah-Hartman
38c91d1d55 tty: add SPDX identifiers to Kconfig and Makefiles
There were a few Kconfig and Makefiles under drivers/tty/ that were
missing a SPDX identifier.  Fix that up so that automated tools can
properly classify all kernel source files.

Cc: Jiri Slaby <jslaby@suse.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-04 18:48:43 +02:00
Greg Kroah-Hartman
b63d443be4 Merge 5.1-rc3 into tty-next
We want the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-01 07:40:47 +02:00
Andy Shevchenko
6b77908fea serial: sc16is7xx: Drop of_match_ptr() use
There is an ACPI method to enumerate such devices via specific ACPI ID
and use of compatible strings. It will not work for the drivers which
have no OF match ID table present.

Reported-by: Georgii Staroselskii <georgii.staroselskii@emlid.com>
Tested-By: Georgii Staroselskii <georgii.staroselskii@emlid.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-28 00:30:51 +09:00
Andy Shevchenko
00d9f0c654 serial: sc16is7xx: Switch to use device_get_match_data()
Instead of open coded variants, switch to direct use of
device_get_match_data().

Tested-By: Georgii Staroselskii <georgii.staroselskii@emlid.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-28 00:30:51 +09:00
Andy Shevchenko
24bc6e68ef serial: sc16is7xx: Respect clock-frequency property
If the property is provided and there are no other possibilities to detect
UART clock frequency, use it as a fallback.

Tested-By: Georgii Staroselskii <georgii.staroselskii@emlid.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-28 00:30:50 +09:00
Lanqing Liu
f4487db58e serial: sprd: Add DMA mode support
Add DMA mode support for the Spreadtrum serial controller.

Signed-off-by: Lanqing Liu <lanqing.liu@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-28 00:30:01 +09:00
Lanqing Liu
4007098f4c serial: sprd: Add power management for the Spreadtrum serial controller
This patch adds power management for the Spreadtrum serial controller.

Signed-off-by: Lanqing Liu <lanqing.liu@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-28 00:30:00 +09:00
YueHaibing
9828def35a serial: 8250_fintek: Make fintek_8250_set_termios static
Fix sparse warning:

drivers/tty/serial/8250/8250_fintek.c:306:6: warning:
 symbol 'fintek_8250_set_termios' was not declared. Should it be static?

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-28 00:29:03 +09:00
Wentao Wang
3ec8002951 Disable kgdboc failed by echo space to /sys/module/kgdboc/parameters/kgdboc
Echo "" to /sys/module/kgdboc/parameters/kgdboc will fail with "No such
device” error.

This is caused by function "configure_kgdboc" who init err to ENODEV
when the config is empty (legal input) the code go out with ENODEV
returned.

Fixes: 2dd4531686 ("kgdboc: Fix restrict error")
Signed-off-by: Wentao Wang <witallwang@gmail.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-28 00:27:48 +09:00
Razvan Stefanescu
69646d7a36 tty/serial: atmel: RS485 HD w/DMA: enable RX after TX is stopped
In half-duplex operation, RX should be started after TX completes.

If DMA is used, there is a case when the DMA transfer completes but the
TX FIFO is not emptied, so the RX cannot be restarted just yet.

Use a boolean variable to store this state and rearm TX interrupt mask
to be signaled again that the transfer finished. In interrupt transmit
handler this variable is used to start RX. A warning message is generated
if RX is activated before TX fifo is cleared.

Fixes: b389f173aa ("tty/serial: atmel: RS485 half duplex w/DMA: enable
RX after TX is done")
Signed-off-by: Razvan Stefanescu <razvan.stefanescu@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-28 00:27:48 +09:00
Razvan Stefanescu
f304098313 tty/serial: atmel: Add is_half_duplex helper
Use a helper function to check that a port needs to use half duplex
communication, replacing several occurrences of multi-line bit checking.

Fixes: b389f173aa ("tty/serial: atmel: RS485 half duplex w/DMA: enable RX after TX is done")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Razvan Stefanescu <razvan.stefanescu@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-28 00:27:48 +09:00
Andy Shevchenko
5ba846b1ee dmaengine: idma64: Use actual device for DMA transfers
Intel IOMMU, when enabled, tries to find the domain of the device,
assuming it's a PCI one, during DMA operations, such as mapping or
unmapping. Since we are splitting the actual PCI device to couple of
children via MFD framework (see drivers/mfd/intel-lpss.c for details),
the DMA device appears to be a platform one, and thus not an actual one
that performs DMA. In a such situation IOMMU can't find or allocate
a proper domain for its operations. As a result, all DMA operations are
failed.

In order to fix this, supply parent of the platform device
to the DMA engine framework and fix filter functions accordingly.

We may rely on the fact that parent is a real PCI device, because no
other configuration is present in the wild.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [for tty parts]
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-03-21 19:48:26 +05:30
Hoan Nguyen An
93bcefd4c6 serial: sh-sci: Fix setting SCSCR_TIE while transferring data
We disable transmission interrupt (clear SCSCR_TIE) after all data has been transmitted
(if uart_circ_empty(xmit)). While transmitting, if the data is still in the tty buffer,
re-enable the SCSCR_TIE bit, which was done at sci_start_tx().
This is unnecessary processing, wasting CPU operation if the data transmission length is large.
And further, transmit end, FIFO empty bits disabling have also been performed in the step above.

Signed-off-by: Hoan Nguyen An <na-hoan@jinso.co.jp>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19 15:37:44 +01:00
Petr Štetiar
72ff51d8dd serial: ar933x_uart: Fix build failure with disabled console
Andrey has reported on OpenWrt's bug tracking system[1], that he
currently can't use ar93xx_uart as pure serial UART without console
(CONFIG_SERIAL_8250_CONSOLE and CONFIG_SERIAL_AR933X_CONSOLE undefined),
because compilation ends with following error:

 ar933x_uart.c: In function 'ar933x_uart_console_write':
 ar933x_uart.c:550:14: error: 'struct uart_port' has no
                               member named 'sysrq'

So this patch moves all the code related to console handling behind
series of CONFIG_SERIAL_AR933X_CONSOLE ifdefs.

1. https://bugs.openwrt.org/index.php?do=details&task_id=2152

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Andrey Batyiev <batyiev@gmail.com>
Reported-by: Andrey Batyiev <batyiev@gmail.com>
Tested-by: Andrey Batyiev <batyiev@gmail.com>
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19 15:37:44 +01:00
Nathan Chancellor
c5cbc78acf tty: serial: qcom_geni_serial: Initialize baud in qcom_geni_console_setup
When building with -Wsometimes-uninitialized, Clang warns:

drivers/tty/serial/qcom_geni_serial.c:1079:6: warning: variable 'baud'
is used uninitialized whenever 'if' condition is false
[-Wsometimes-uninitialized]

It's not wrong; when options is NULL, baud has no default value. Use
9600 as that is a sane default.

Link: https://github.com/ClangBuiltLinux/linux/issues/395
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19 15:37:44 +01:00
Mao Wenan
ac0cdb3d99 sc16is7xx: missing unregister/delete driver on error in sc16is7xx_init()
Add the missing uart_unregister_driver() and i2c_del_driver() before return
from sc16is7xx_init() in the error handling case.

Signed-off-by: Mao Wenan <maowenan@huawei.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19 15:37:44 +01:00