Commit Graph

4349 Commits

Author SHA1 Message Date
Linus Torvalds
563873318d Merge branch 'printk-cleanups'
Merge my system logging cleanups, triggered by the broken '\n' patches.

The line continuation handling has been broken basically forever, and
the code to handle the system log records was both confusing and
dubious.  And it would do entirely the wrong thing unless you always had
a terminating newline, partly because it couldn't actually see whether a
message was marked KERN_CONT or not (but partly because the LOG_CONT
handling in the recording code was rather confusing too).

This re-introduces a real semantically meaningful KERN_CONT, and fixes
the few places I noticed where it was missing.  There are probably more
missing cases, since KERN_CONT hasn't actually had any semantic meaning
for at least four years (other than the checkpatch meaning of "no log
level necessary, this is a continuation line").

This also allows the combination of KERN_CONT and a log level.  In that
case the log level will be ignored if the merging with a previous line
is successful, but if a new record is needed, that new record will now
get the right log level.

That also means that you can at least in theory combine KERN_CONT with
the "pr_info()" style helpers, although any use of pr_fmt() prefixing
would make that just result in a mess, of course (the prefix would end
up in the middle of a continuing line).

* printk-cleanups:
  printk: make reading the kernel log flush pending lines
  printk: re-organize log_output() to be more legible
  printk: split out core logging code into helper function
  printk: reinstate KERN_CONT for printing continuation lines
2016-10-10 09:29:50 -07:00
Linus Torvalds
4bcc595ccd printk: reinstate KERN_CONT for printing continuation lines
Long long ago the kernel log buffer was a buffered stream of bytes, very
much like stdio in user space.  It supported log levels by scanning the
stream and noticing the log level markers at the beginning of each line,
but if you wanted to print a partial line in multiple chunks, you just
did multiple printk() calls, and it just automatically worked.

Except when it didn't, and you had very confusing output when different
lines got all mixed up with each other.  Then you got fragment lines
mixing with each other, or with non-fragment lines, because it was
traditionally impossible to tell whether a printk() call was a
continuation or not.

To at least help clarify the issue of continuation lines, we added a
KERN_CONT marker back in 2007 to mark continuation lines:

  4749252776 ("printk: add KERN_CONT annotation").

That continuation marker was initially an empty string, and didn't
actuall make any semantic difference.  But it at least made it possible
to annotate the source code, and have check-patch notice that a printk()
didn't need or want a log level marker, because it was a continuation of
a previous line.

To avoid the ambiguity between a continuation line that had that
KERN_CONT marker, and a printk with no level information at all, we then
in 2009 made KERN_CONT be a real log level marker which meant that we
could now reliably tell the difference between the two cases.

  5fd29d6ccb ("printk: clean up handling of log-levels and newlines")

and we could take advantage of that to make sure we didn't mix up
continuation lines with lines that just didn't have any loglevel at all.

Then, in 2012, the kernel log buffer was changed to be a "record" based
log, where each line was a record that has a loglevel and a timestamp.

You can see the beginning of that conversion in commits

  e11fea92e1 ("kmsg: export printk records to the /dev/kmsg interface")
  7ff9554bb5 ("printk: convert byte-buffer to variable-length record buffer")

with a number of follow-up commits to fix some painful fallout from that
conversion.  Over all, it took a couple of months to sort out most of
it.  But the upside was that you could have concurrent readers (and
writers) of the kernel log and not have lines with mixed output in them.

And one particular pain-point for the record-based kernel logging was
exactly the fragmentary lines that are generated in smaller chunks.  In
order to still log them as one recrod, the continuation lines need to be
attached to the previous record properly.

However the explicit continuation record marker that is actually useful
for this exact case was actually removed in aroundm the same time by commit

  61e99ab8e3 ("printk: remove the now unnecessary "C" annotation for KERN_CONT")

due to the incorrect belief that KERN_CONT wasn't meaningful.  The
ambiguity between "is this a continuation line" or "is this a plain
printk with no log level information" was reintroduced, and in fact
became an even bigger pain point because there was now the whole
record-level merging of kernel messages going on.

This patch reinstates the KERN_CONT as a real non-empty string marker,
so that the ambiguity is fixed once again.

But it's not a plain revert of that original removal: in the four years
since we made KERN_CONT an empty string again, not only has the format
of the log level markers changed, we've also had some usage changes in
this area.

For example, some ACPI code seems to use KERN_CONT _together_ with a log
level, and now uses both the KERN_CONT marker and (for example) a
KERN_INFO marker to show that it's an informational continuation of a
line.

Which is actually not a bad idea - if the continuation line cannot be
attached to its predecessor, without the log level information we don't
know what log level to assign to it (and we traditionally just assigned
it the default loglevel).  So having both a log level and the KERN_CONT
marker is not necessarily a bad idea, but it does mean that we need to
actually iterate over potentially multiple markers, rather than just a
single one.

Also, since KERN_CONT was still conceptually needed, and encouraged, but
didn't actually _do_ anything, we've also had the reverse problem:
rather than having too many annotations it has too few, and there is bit
rot with code that no longer marks the continuation lines with the
KERN_CONT marker.

So this patch not only re-instates the non-empty KERN_CONT marker, it
also fixes up the cases of bit-rot I noticed in my own logs.

There are probably other cases where KERN_CONT will be needed to be
added, either because it is new code that never dealt with the need for
KERN_CONT, or old code that has bitrotted without anybody noticing.

That said, we should strive to avoid the need for KERN_CONT.  It does
result in real problems for logging, and should generally not be seen as
a good feature.  If we some day can get rid of the feature entirely,
because nobody does any fragmented printk calls, that would be lovely.

But until that point, let's at mark the code that relies on the hacky
multi-fragment kernel printk's.  Not only does it avoid the ambiguity,
it also annotates code as "maybe this would be good to fix some day".

(That said, particularly during single-threaded bootup, the downsides of
KERN_CONT are very limited.  Things get much hairier when you have
multiple threads going on and user level reading and writing logs too).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-09 12:23:38 -07:00
Linus Torvalds
e6dce825fb TTY/Serial patches for 4.9-rc1
Here is the big TTY and Serial patch set for 4.9-rc1.
 
 It also includes some drivers/dma/ changes, as those were needed by some
 serial drivers, and they were all acked by the DMA maintainer.  Also in
 here is the long-suffering ACPI SPCR patchset, which was passed around
 from maintainer to maintainer like a hot-potato.  Seems I was the
 sucker^Wlucky one.  All of those patches have been acked by the various
 subsystem maintainers as well.
 
 All of this has been in linux-next with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty and serial updates from Greg KH:
 "Here is the big tty and serial patch set for 4.9-rc1.

  It also includes some drivers/dma/ changes, as those were needed by
  some serial drivers, and they were all acked by the DMA maintainer.

  Also in here is the long-suffering ACPI SPCR patchset, which was
  passed around from maintainer to maintainer like a hot-potato. Seems I
  was the sucker^Wlucky one. All of those patches have been acked by the
  various subsystem maintainers as well.

  All of this has been in linux-next with no reported issues"

* tag 'tty-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (111 commits)
  Revert "serial: pl011: add console matching function"
  MAINTAINERS: update entry for atmel_serial driver
  serial: pl011: add console matching function
  ARM64: ACPI: enable ACPI_SPCR_TABLE
  ACPI: parse SPCR and enable matching console
  of/serial: move earlycon early_param handling to serial
  Revert "drivers/tty: Explicitly pass current to show_stack"
  tty: amba-pl011: Don't complain on -EPROBE_DEFER when no irq
  nios2: dts: 10m50: Add tx-threshold parameter
  serial: 8250: Set Altera 16550 TX FIFO Threshold
  serial: 8250: of: Load TX FIFO Threshold from DT
  Documentation: dt: serial: Add TX FIFO threshold parameter
  drivers/tty: Explicitly pass current to show_stack
  serial: imx: Fix DCD reading
  serial: stm32: mark symbols static where possible
  serial: xuartps: Add some register initialisation to cdns_early_console_setup()
  serial: xuartps: Removed unwanted checks while reading the error conditions
  serial: xuartps: Rewrite the interrupt handling logic
  serial: stm32: use mapbase instead of membase for DMA
  tty/serial: atmel: fix fractional baud rate computation
  ...
2016-10-03 20:11:49 -07:00
Linus Torvalds
7a53eea1f7 Char/Misc driver update for 4.9-rc1
Here's the "big" char and misc driver update for 4.9-rc1.
 
 Lots of little things here, all over the driver tree for subsystems that
 flow through me.  Nothing major that I can discern, full details are in
 the shortlog.
 
 All have been in the linux-next tree with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here's the "big" char and misc driver update for 4.9-rc1.

  Lots of little things here, all over the driver tree for subsystems
  that flow through me. Nothing major that I can discern, full details
  are in the shortlog.

  All have been in the linux-next tree with no reported issues"

* tag 'char-misc-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (144 commits)
  drivers/misc/hpilo: Changes to support new security states in iLO5 FW
  at25: fix debug and error messaging
  misc/genwqe: ensure zero initialization
  vme: fake: remove unexpected unlock in fake_master_set()
  vme: fake: mark symbols static where possible
  spmi: pmic-arb: Return an error code if sanity check fails
  Drivers: hv: get rid of id in struct vmbus_channel
  Drivers: hv: make VMBus bus ids persistent
  mcb: Add a dma_device to mcb_device
  mcb: Enable PCI bus mastering by default
  mei: stop the stall timer worker if not needed
  clk: probe common clock drivers earlier
  vme: fake: fix build for 64-bit dma_addr_t
  ttyprintk: Neaten and simplify printing
  mei: me: add kaby point device ids
  coresight: tmc: mark symbols static where possible
  coresight: perf: deal with error condition properly
  Drivers: hv: hv_util: Avoid dynamic allocation in time synch
  fpga manager: Add hardware dependency to Zynq driver
  Drivers: hv: utils: Support TimeSync version 4.0 protocol samples.
  ...
2016-10-03 19:57:49 -07:00
Rafael J. Wysocki
52ff5adc1f Merge branch 'device-properties'
* device-properties:
  serial: 8250_dw: Add quirk for APM X-Gene SoC
  ACPI / LPSS: Provide build-in properties of the UART
  ACPI / APD: Provide build-in properties of the UART
  driver core: Don't leak secondary fwnode on device removal
2016-10-02 01:35:42 +02:00
Greg Kroah-Hartman
08bf215900 Revert "serial: pl011: add console matching function"
This reverts commit 8b8f347d3a as it
causes build errors in linux-next

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Aleksey Makarov <aleksey.makarov@linaro.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-30 07:46:35 +02:00
Aleksey Makarov
8b8f347d3a serial: pl011: add console matching function
This patch adds function pl011_console_match() that implements
method match of struct console.  It allows to match consoles against
data specified in a string, for example taken from command line or
compiled by ACPI SPCR table handler.

Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Tested-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-28 17:46:57 +02:00
Aleksey Makarov
ad1696f6f0 ACPI: parse SPCR and enable matching console
'ARM Server Base Boot Requiremets' [1] mentions SPCR (Serial Port
Console Redirection Table) [2] as a mandatory ACPI table that
specifies the configuration of serial console.

Defer initialization of DT earlycon until ACPI/DT decision is made.

Parse the ACPI SPCR table, setup earlycon if required,
enable specified console.

Thanks to Peter Hurley for explaining how this should work.

[1] http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.den0044a/index.html
[2] https://msdn.microsoft.com/en-us/library/windows/hardware/dn639132(v=vs.85).aspx

Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Tested-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-28 17:46:46 +02:00
Leif Lindholm
d503187b6c of/serial: move earlycon early_param handling to serial
We have multiple "earlycon" early_param handlers - merge the DT one into
the main earlycon one.  It's a cleanup that also will be useful
to defer setting up DT console until ACPI/DT decision is made.

Rename the exported function to avoid clashing with the function from
arch/microblaze/kernel/prom.c

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Tested-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-28 17:43:15 +02:00
Greg Kroah-Hartman
094a32626f Revert "drivers/tty: Explicitly pass current to show_stack"
This reverts commit 9f12cea96f.

Mark writes:
	Unfortunately, this patch will result in erroneous stack traces
	on some architectures. Sorry about this; I should have verified
	this more thoroughly before sending the series out.

	Please drop the patch at your earliest convenience.

Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-28 08:12:27 +02:00
Kefeng Wang
35aa33cf0b tty: amba-pl011: Don't complain on -EPROBE_DEFER when no irq
Don't complain on -EPROBE_DEFER when attempting to get the irq.
the driver probe will be retried later.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:57:16 +02:00
Thor Thayer
8e5470c983 serial: 8250: Set Altera 16550 TX FIFO Threshold
The Altera 16550 soft IP UART requires 2 additional registers for
TX FIFO threshold support. These 2 registers enable the TX FIFO
Low Watermark and set the TX FIFO Low Watermark.
Set the TX FIFO threshold to the FIFO size - tx_loadsz.

Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:55:50 +02:00
Thor Thayer
ffea043965 serial: 8250: of: Load TX FIFO Threshold from DT
Initialize the tx_loadsz parameter from passed in devicetree
tx-threshold parameter.
The tx_loadsz is calculated as the number of bytes to fill FIFO
when tx-threshold is triggered.

Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:55:49 +02:00
Mark Rutland
9f12cea96f drivers/tty: Explicitly pass current to show_stack
As noted in commit:

  81539169f2 ("x86/dumpstack: Remove NULL task pointer convention")

... having a NULL task parameter imply current leads to subtle bugs in stack
walking code (so far seen on both 86 and arm64), makes callsites harder to
read, and is unnecessary as all callers have access to current.

As a step towards removing the problematic NULL-implies-current idiom entirely,
have the sysrq code explicitly pass current to show_stack.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:55:27 +02:00
Sascha Hauer
4b75f80003 serial: imx: Fix DCD reading
The USR2_DCDIN bit is tested for in register usr1. As the name
suggests the usr2 register should be used instead. This fixes
reading the Carrier detect status.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Fixes: 90ebc48386 ("serial: imx: repair and complete handshaking")
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: <stable@vger.kernel.org> # 4.5+
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:55:27 +02:00
Baoyou Xie
b97055bcf1 serial: stm32: mark symbols static where possible
We get 2 warnings when building kernel with W=1:
drivers/tty/serial/stm32-usart.c:63:5: warning: no previous prototype for 'stm32_pending_rx' [-Wmissing-prototypes]
drivers/tty/serial/stm32-usart.c:88:15: warning: no previous prototype for 'stm32_get_char' [-Wmissing-prototypes]

In fact, these two functions are only used in the file in which they are
declared and don't need a declaration, but can be made static.

So this patch marks these functions with 'static'.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:55:27 +02:00
Scott Telford
c41251b175 serial: xuartps: Add some register initialisation to cdns_early_console_setup()
Add initialisation of control register and baud rate to
cdns_early_console_setup(), required when running kernel standalone
without a boot loader. Baud rate is only initialised when specified in
earlycon command-line option, otherwise it is assumed this has been
set by a boot loader. Updated Documentation/kernel-parameters.txt
accordingly.

Signed-off-by: Scott Telford <stelford@cadence.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:54:41 +02:00
Nava kishore Manne
212d249b6a serial: xuartps: Removed unwanted checks while reading the error conditions
This patch Remove the unwated checks while reading the parity,framing,
overrun and Break detection errors.

Signed-off-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
[stelford@cadence.com: cherry picked from
https://github.com/Xilinx/linux-xlnx commit
b1cf74970df5470ffbc8e7876a9edf5e3498ef94]
Signed-off-by: Scott Telford <stelford@cadence.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:54:41 +02:00
Anirudha Sarangi
c8dbdc842d serial: xuartps: Rewrite the interrupt handling logic
The existing interrupt handling logic has following issues.
- Upon a parity error with default configuration, the control
  never comes out of the ISR thereby hanging Linux.
- The error handling logic around framing and parity error are buggy.
  There are chances that the errors will never be captured.
This patch ensures that the status registers are cleared on all cases so
that a hang situation never arises.

Signed-off-by: Anirudha Sarangi <anirudh@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
[stelford@cadence.com: cherry picked from
https://github.com/Xilinx/linux-xlnx commit
ac297e20d399850d7a8e373b6eccf2e183c15165 with manual conflict resolution]
Signed-off-by: Scott Telford <stelford@cadence.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:54:41 +02:00
Arnd Bergmann
8e5481d98b serial: stm32: use mapbase instead of membase for DMA
Building this driver with a 64-bit dma_addr_t type results in
a compiler warning:

drivers/tty/serial/stm32-usart.c: In function 'stm32_of_dma_rx_probe':
drivers/tty/serial/stm32-usart.c:746:20: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
drivers/tty/serial/stm32-usart.c: In function 'stm32_of_dma_tx_probe':
drivers/tty/serial/stm32-usart.c:818:20: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]

While the type conversion here is harmless, this hints at a different
problem: we pass an __iomem pointer into a DMA engine, which expects
a phys_addr_t. This happens to work because stm32 has no MMU and
ioremap() is an identity mapping here, but it's still an incorrect
API use. Using dma_addr_t is doubly wrong here, because that would
be the result of dma_map_single() rather than the physical address.

Using the mapbase instead fixes multiple issues:

- the warning is gone
- we don't go through ioremap in error
- the cast is gone, making it use the correct resource_size_t/phys_addr_t
  type in the process.

Fixes: 3489187204 ("serial: stm32: adding dma support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:54:03 +02:00
Alexey Starikovskiy
36131cdfef tty/serial: atmel: fix fractional baud rate computation
The problem with previous code was it rounded values in wrong
place and produced wrong baud rate in some cases.

Signed-off-by: Alexey Starikovskiy <aystarik@gmail.com>
[nicolas.ferre@atmel.com: port to newer kernel and add commit log]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27 12:54:03 +02:00
Anirudha Sarangi
a3081893ca serial: xuartps: Do not enable parity error interrupt
The patch makes changes not to enable parity error interrupt.
With the current implementation, each parity error results in
two distinct interrupts (almost always). The first one is normal
parity error interrupt with no data in the fifo and the second one
is a proper Rx interrupt with the received data in the fifo. By
disabling parity error interrupt we still ensure handling of
parity errors as for the Rx fifo interrupt the parity error still
shows up in the interrupt status register. Considering the fact
that the by default INPCK and IGNPAR are not set, this is the
optimal implementation for parity error handling.

Signed-off-by: Anirudha Sarangi <anirudh@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
[stelford@cadence.com: cherry picked from
https://github.com/Xilinx/linux-xlnx commit
bf9f610b445e2c9ed33c41e1e0e30b43be4e1f97 with manual conflict
resolution]
Signed-off-by: Scott Telford <stelford@cadence.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:49:55 +02:00
Alexandre TORGUE
87f1f809c9 serial: stm32: fix uart enable management
Signed-off-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:48:56 +02:00
Alexandre TORGUE
01d32d7161 serial: stm32: fix spin_lock management
Signed-off-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:48:55 +02:00
Alexandre TORGUE
3489187204 serial: stm32: adding dma support
This patch adds dma mode support for rx and tx
with pio mode as fallback in case of dma error.

Signed-off-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:48:55 +02:00
Alexandre TORGUE
511c7b1baa serial: stm32: clock disabling management
Keep the clock enabled at the end of stm32_init_port
but disable it in stm32_serial_remove.
Note that stm32_pm function is there to manage the
clock at runtime.

Signed-off-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:48:55 +02:00
Alexandre TORGUE
59bed2dfe0 serial: stm32: correct flow control property spelling
"st,hw-flow-ctrl" property is documented in device tree
binding whereas "auto-flow-control" was used in the code.
The driver is now aligned with the binding name
"st,hw-flow-ctrl".

Signed-off-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:48:55 +02:00
Alexandre TORGUE
a14f66a427 serial: stm32: disable tx and rx during shutdown
Signed-off-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:48:55 +02:00
Alexandre TORGUE
bc5a0b55ba serial: stm32: header file creation
Signed-off-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:48:55 +02:00
Alexandre TORGUE
ada8618ff3 serial: stm32: adding support for stm32f7
Register offset management rework to support both
stm32f4 (default) and stm32f7. Driver rework to
ensure same functional level on both stm32f4 and
stm32f7: no new feature in this version yet.

Signed-off-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:48:55 +02:00
Nava kishore Manne
27b17ae073 tty: serial: xuartps: Wait for rx and tx reset done status
After issuing the reset, driver is not checking the rx and tx reset
done status. So, modified driver to wait for the reset done status.

Signed-off-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:46:12 +02:00
Nava kishore Manne
3816b2f886 serial: xuartps: Adds RXBS register support for zynqmp
This patch adds RXBS register access support for zynqmp.
To avoid the corner error conditions it will consider only
RXBS[2:0] bits while checking the error conditions
(Parity,Framing and BRAK).

Signed-off-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:46:12 +02:00
Jiri Olsa
54f19b4a67 tty/serial/8250: Touch NMI watchdog in wait_for_xmitr
First loop in wait_for_xmitr could also trigger NMI
watchdog in case reading from the port is slow:

  PID: 0      TASK: ffffffff819c1460  CPU: 0   COMMAND: "swapper/0"
   #0 [ffff88019f405e58] crash_nmi_callback at ffffffff8104d382
   #1 [ffff88019f405e68] nmi_handle at ffffffff8168ead9
   #2 [ffff88019f405eb0] do_nmi at ffffffff8168ec53
   #3 [ffff88019f405ef0] end_repeat_nmi at ffffffff8168df13
      [exception RIP: delay_tsc+50]
      RIP: ffffffff81325642  RSP: ffff88019f403bb0  RFLAGS: 00000083
      RAX: 00000000000005c8  RBX: ffffffff81f83000  RCX: 0000024e4fb88a8b
      RDX: 0000024e4fb89053  RSI: 0000000000000000  RDI: 00000000000007d1
      RBP: ffff88019f403bb0   R8: 000000000000000a   R9: 0000000000000000
      R10: 0000000000000000  R11: ffff88019f403ad6  R12: 000000000000250f
      R13: 0000000000000020  R14: ffffffff81d360c7  R15: 0000000000000047
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
  --- <NMI exception stack> ---
   #4 [ffff88019f403bb0] delay_tsc at ffffffff81325642
   #5 [ffff88019f403bb8] __const_udelay at ffffffff813255a8
   #6 [ffff88019f403bc8] wait_for_xmitr at ffffffff81404390
   #7 [ffff88019f403bf0] serial8250_console_putchar at ffffffff8140455c
   #8 [ffff88019f403c10] uart_console_write at ffffffff813ff00a
   #9 [ffff88019f403c40] serial8250_console_write at ffffffff814044ae
  #10 [ffff88019f403c88] call_console_drivers.constprop.15 at ffffffff81086b01
  #11 [ffff88019f403cb0] console_unlock at ffffffff8108842f
  #12 [ffff88019f403ce8] vprintk_emit at ffffffff81088834
  #13 [ffff88019f403d58] vprintk_default at ffffffff81088ba9
  #14 [ffff88019f403d68] printk at ffffffff8167f034

Adding touch_nmi_watchdog call to the first loop as well.

Reported-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:45:08 +02:00
Jan Kiszka
b6fce7382d serial: 8250_pci: Use symbolic constants for EXAR's MPIO registers
Less magic that only requires comments.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:45:08 +02:00
Shawn Guo
e06690bff6 tty: amba-pl011: uart_amba_port is not available with earlycon function
Commit 0e125a5fac ("tty: amba-pl011: define flag register bits for ZTE
device") changes earlycon function pl011_putc() to use a pointer to
uart_amba_port.  This causes a regression when earlycon is enabled,
because uart_amba_port is not available yet at earlycon time.  Let's
revert the change on pl011_putc() to fix the regression.

The earlycon support for ZTE device can probably be added later by
declaring a new earlycon setup function with a vendor specific
compatible.

Reported-by: Sudeep Holla <sudeep.holla@arm.com>
Fixes: 0e125a5fac ("tty: amba-pl011: define flag register bits for ZTE device")
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:45:08 +02:00
Wei Yongjun
1664bc40d3 serial: mxs-auart: Fix missing clk_disable_unprepare() on error in mxs_get_clks()
Commit 5d7519dfc9 ("serial: mxs-auart: Disable clock on error path")
try to disable clock on error path, but still missing the clk_set_rate()
error handling path.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:45:08 +02:00
Adam Borowski
fadb424408 vt: Emulate \e[100-107m (bright background colors).
For now, these fall back to regular (dark) colors.

It'd be tempting to replace blink with bright backgrounds, as permitted by
CGA/VGA -- we already muck with the other programmable bit (foreground
brightness vs 512 character font).  This would bring vgacon in line with
fbcon, which doesn't support blink anywhere but on some drivers renders
that bit as bright background.  If that is done, this commit should be
amended to be one of ways of setting that bit.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:41:54 +02:00
Adam Borowski
cc67dc28b3 vt: Support \e[90-97m (bright foreground colors).
These codes are supported by all major terminals, thus they occasionally see
some use despite being redundant with \e[38;5;(x+8)m or (less exactly)
\e[1;3(x)m.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:41:54 +02:00
Adam Borowski
3e7ec4a0e6 vt: Drop a no longer true comment.
Some guy went on a patching spree, adding 24-bit colour support all around:
https://gist.github.com/XVilka/8346728

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:41:54 +02:00
Adam Borowski
0bf1f4a8a3 vt: Make a comparison <= for readability.
All other uses of vc_npar are inclusive (save for < NPAR) which raises
eyebrows, so let's at least do so consistently.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:41:54 +02:00
Adam Borowski
669e0a51b1 vt: Fix a read-past-array in vc_t416_color().
This makes it show up on UBSAN:
perl -e 'for (0..15) {my @x=("0")x$_;push @x,qw(38 2 64 128 192 4);printf
"\e[%smAfter %d zeroes.\e[0m\n", join(";",@x[0..($_+5<15?$_+5:15)]), $_}'

Seems harmless: if you can programmatically read attributes of a vt
character (/dev/vcsa*), multiple probes can obtain parts of vt_mode then
lowest byte (5th on 64-bit big-endian) of a pointer.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22 11:41:54 +02:00
Kees Cook
d2ec3f77de pty: make ptmx file ops read-only after init
The ptmx_fops structure is only changed during init, so mark it as such.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 12:47:03 +02:00
Fabien Lahoudere
e5e8960236 serial: imx: Replace dmaengine old API
dmaengine_terminate_all() is deprecated and should be replaced by
dmaengine_terminate_sync() in non-atomic context or dmaengine_terminate_async()
with dmaengine_synchronize().

See commit b36f09c3c4 ("dmaengine: Add transfer termination synchronization support")

Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 12:35:49 +02:00
Andy Shevchenko
a5a2b13074 serial: core: fix potential NULL pointer dereference
The commit 761ed4a945 ("tty: serial_core: convert uart_close to use
tty_port_close") refactored uart_close() to use tty_port_close().  At the same
time it introduced a potential NULL pointer dereference. Rearrange the code to
avoid kernel crash.

Fixes: 761ed4a945 ("tty: serial_core: convert uart_close to use tty_port_close")
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 12:35:49 +02:00
Richard Genoud
0ae9fdefb6 BUG: atmel_serial: Interrupts not disabled on close
Since commit 18dfef9c7f ("serial: atmel: convert to irq handling
provided mctrl-gpio"), interrupts from GPIOs are not disabled any more
when the serial port is closed, leading to an oops when the one of the
input pin is toggled (CTS/DSR/DCD/RNG).

This is only the case if those pins are used as GPIOs, i.e. declared
like that:
usart1: serial@f8020000 {
        /* CTS and DTS will be handled by GPIO */
        status = "okay";
        rts-gpios = <&pioB 17 GPIO_ACTIVE_LOW>;
        cts-gpios = <&pioB 16 GPIO_ACTIVE_LOW>;
        dtr-gpios = <&pioB 14 GPIO_ACTIVE_LOW>;
        dsr-gpios = <&pioC 31 GPIO_ACTIVE_LOW>;
        rng-gpios = <&pioB 12 GPIO_ACTIVE_LOW>;
        dcd-gpios = <&pioB 15 GPIO_ACTIVE_LOW>;
};

That's because modem interrupts used to be freed in atmel_shutdown().
After commit 18dfef9c7f ("serial: atmel: convert to irq handling
provided mctrl-gpio"), this code was just removed.
Calling atmel_disable_ms() disables the interrupts and everything works
fine again.

Tested on at91sam9g35-cm

(This patch doesn't apply on -stable kernels, fixes for 4.4 and 4.7 will
be sent after this one is applied.)

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Fixes: 18dfef9c7f ("serial: atmel: convert to irq handling provided mctrl-gpio")
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 12:35:49 +02:00
Wei Yongjun
33ddca08bf tty: serial: fsl_lpuart: use GFP_ATOMIC under spin lock
The function lpuart_start_rx_dma() is called from several
places, in some of which, such as lpuart_startup(), a lock
be held here, so we should use GFP_ATOMIC when a lock is held.

Fixes: 5887ad43ee ("tty: serial: fsl_lpuart: Use cyclic DMA for Rx")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 12:35:49 +02:00
Liu Xiang
c164b008b6 serial: max310x: Set IRQF_TRIGGER_FALLING flag when dev.of_node is not NULL
When dev.of_node is not NULL, we also need to set IRQF_TRIGGER_FALLING
flag, otherwise it may cause uncertain interrupts.

Signed-off-by: Liu Xiang <liu.xiang6@zte.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 12:35:49 +02:00
Wei Yongjun
0d2665b6bc serial: mxs-auart: Use PTR_ERR_OR_ZERO() to simplify the code
Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR.

Generated by: scripts/coccinelle/api/ptr_ret.cocci

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-13 18:54:34 +02:00
Fabio Estevam
5d7519dfc9 serial: mxs-auart: Disable clock on error path
We should disable the previously acquired clock when enabling s->clk
fails.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-13 18:54:34 +02:00
Alexander Sverdlin
8b2303de39 serial: core: Fix handling of options after MMIO address
Guenter Roeck reported a regression caused by commit "serial: earlycon:
Extend earlycon command line option to support 64-bit addresses":

console= and earlycon= options have the following format:
...,<addr>,<options>

Historically used here simple_strtoul() had no problems with comma, but the
new and recommended kstrtoull() requires null-terminated string and returns
-EINVAL in case there are "options" at the end. There is no recommended to
use function currently that will support it, so stick to obsolete
simple_strtoull() variant.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-13 18:54:34 +02:00