Commit Graph

4052 Commits

Author SHA1 Message Date
Linus Torvalds 8ead9dd547 devpts: more pty driver interface cleanups
This is more prep-work for the upcoming pty changes.  Still just code
cleanup with no actual semantic changes.

This removes a bunch pointless complexity by just having the slave pty
side remember the dentry associated with the devpts slave rather than
the inode.  That allows us to remove all the "look up the dentry" code
for when we want to remove it again.

Together with moving the tty pointer from "inode->i_private" to
"dentry->d_fsdata" and getting rid of pointless inode locking, this
removes about 30 lines of code.  Not only is the end result smaller,
it's simpler and easier to understand.

The old code, for example, depended on the d_find_alias() to not just
find the dentry, but also to check that it is still hashed, which in
turn validated the tty pointer in the inode.

That is a _very_ roundabout way to say "invalidate the cached tty
pointer when the dentry is removed".

The new code just does

	dentry->d_fsdata = NULL;

in devpts_pty_kill() instead, invalidating the tty pointer rather more
directly and obviously.  Don't do something complex and subtle when the
obvious straightforward approach will do.

The rest of the patch (ie apart from code deletion and the above tty
pointer clearing) is just switching the calling convention to pass the
dentry or file pointer around instead of the inode.

Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc: Jann Horn <jann@thejh.net>
Cc: Greg KH <greg@kroah.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-26 15:47:32 -07:00
Linus Torvalds 8e3ae37acc Serial fixes for 4.6-rc6
Here are 3 serial driver fixes for issues that have been reported.  Two
 are reverts, fixing problems that were in the big TTY/Serial driver
 merge in 4.6-rc1, and the last one is a simple bugfix for a regression
 that showed up in 4.6-rc1 as well.
 
 All have been in linux-next with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull serial fixes from Greg KH:
 "Here are 3 serial driver fixes for issues that have been reported.

  Two are reverts, fixing problems that were in the big TTY/Serial
  driver merge in 4.6-rc1, and the last one is a simple bugfix for a
  regression that showed up in 4.6-rc1 as well.

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

* tag 'tty-4.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "serial: 8250: Add hardware dependency to RT288X option"
  tty/serial/8250: fix RS485 half-duplex RX
  Revert "serial-uartlite: Constify uartlite_be/uartlite_le"
2016-04-23 11:13:46 -07:00
Greg Kroah-Hartman f077b73682 Revert "serial: 8250: Add hardware dependency to RT288X option"
This reverts commit 8d2acdb9fc.

It's causing problems, and somehow I missed that Peter didn't like it at
all :(
So revert it for now until it gets sorted out.

Reported-by: Mason <slash.tmp@free.fr>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Jean Delvare <jdelvare@suse.de>
Cc: Mans Rullgard <mans@mansr.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: John Crispin <blogic@openwrt.org>
Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
2016-04-19 15:17:37 +09:00
Yegor Yefremov 0c66940d58 tty/serial/8250: fix RS485 half-duplex RX
When in half-duplex mode RX will be disabled before TX, but not
enabled after deactivating transmitter. This patch enables
UART_IER_RLSI and UART_IER_RDI interrupts after TX is over.

Cc: Matwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Fixes: e490c9144c ("tty: Add software emulated RS485 support for 8250")
Acked-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-19 15:15:38 +09:00
Sudip Mukherjee 9220ebffda Revert "serial-uartlite: Constify uartlite_be/uartlite_le"
This reverts commit 2905697a82.

The commit introduced two build warnings:
drivers/tty/serial/uartlite.c: In function ‘ulite_request_port’:
drivers/tty/serial/uartlite.c:348:21: warning: assignment discards
			‘const’ qualifier from pointer target type
  port->private_data = &uartlite_be;
                     ^
drivers/tty/serial/uartlite.c:354:22: warning: assignment discards
			‘const’ qualifier from pointer target type
   port->private_data = &uartlite_le;
                      ^

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Cc: Maarten Brock <m.brock@vanmierlo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-19 15:15:38 +09:00
Linus Torvalds 67245ff332 devpts: clean up interface to pty drivers
This gets rid of the horrible notion of having that

    struct inode *ptmx_inode

be the linchpin of the interface between the pty code and devpts.

By de-emphasizing the ptmx inode, a lot of things actually get cleaner,
and we will have a much saner way forward.  In particular, this will
allow us to associate with any particular devpts instance at open-time,
and not be artificially tied to one particular ptmx inode.

The patch itself is actually fairly straightforward, and apart from some
locking and return path cleanups it's pretty mechanical:

 - the interfaces that devpts exposes all take "struct pts_fs_info *"
   instead of "struct inode *ptmx_inode" now.

   NOTE! The "struct pts_fs_info" thing is a completely opaque structure
   as far as the pty driver is concerned: it's still declared entirely
   internally to devpts. So the pty code can't actually access it in any
   way, just pass it as a "cookie" to the devpts code.

 - the "look up the pts fs info" is now a single clear operation, that
   also does the reference count increment on the pts superblock.

   So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get
   ref" operation (devpts_get_ref(inode)), along with a "put ref" op
   (devpts_put_ref()).

 - the pty master "tty->driver_data" field now contains the pts_fs_info,
   not the ptmx inode.

 - because we don't care about the ptmx inode any more as some kind of
   base index, the ref counting can now drop the inode games - it just
   gets the ref on the superblock.

 - the pts_fs_info now has a back-pointer to the super_block. That's so
   that we can easily look up the information we actually need. Although
   quite often, the pts fs info was actually all we wanted, and not having
   to look it up based on some magical inode makes things more
   straightforward.

In particular, now that "devpts_get_ref(inode)" operation should really
be the *only* place we need to look up what devpts instance we're
associated with, and we do it exactly once, at ptmx_open() time.

The other side of this is that one ptmx node could now be associated
with multiple different devpts instances - you could have a single
/dev/ptmx node, and then have multiple mount namespaces with their own
instances of devpts mounted on /dev/pts/.  And that's all perfectly sane
in a model where we just look up the pts instance at open time.

This will eventually allow us to get rid of our odd single-vs-multiple
pts instance model, but this patch in itself changes no semantics, only
an internal binding model.

Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc: Jann Horn <jann@thejh.net>
Cc: Greg KH <greg@kroah.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-18 13:43:02 -07:00
Peter Hurley 5e00bbfbc5 tty: Fix merge of "tty: Refactor tty_open()"
Commit e9036d0662 ("tty: Drop krefs for interrupted tty lock")
fixed a tty reference counting problem introduced in
commit 0bfd464d3f ("tty: Wait interruptibly for tty lock on reopen"),
so v4.5.0 is correct.

However, commit d6203d0c7b ("tty: Refactor tty_open()") moved the
relevant code for 4.6-rc1; correct the merge.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-31 20:49:39 -07:00
Peter Hurley da5a0fc674 tty: Fix UML console breakage
User-Mode Linux supplies an alternate TTY_MAJOR driver for stdio console,
so the noctty check in tty_open() must apply only to VT driver tty0
devnode and not the UML console driver tty0 devnode.

Fixes: 11e1d4aa4d ("tty: Consolidate noctty checks in tty_open()")
Reported-by: Richard Weinberger <richard.weinberger@gmail.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-31 17:14:14 -07:00
Linus Torvalds 55fc733c7e xen: features and fixes for 4.6-rc0
- Make earlyprintk=xen work for HVM guests.
 - Remove module support for things never built as modules.
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Merge tag 'for-linus-4.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from David Vrabel:
 "Features and fixes for 4.6:

  - Make earlyprintk=xen work for HVM guests

  - Remove module support for things never built as modules"

* tag 'for-linus-4.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  drivers/xen: make platform-pci.c explicitly non-modular
  drivers/xen: make sys-hypervisor.c explicitly non-modular
  drivers/xen: make xenbus_dev_[front/back]end explicitly non-modular
  drivers/xen: make [xen-]ballon explicitly non-modular
  xen: audit usages of module.h ; remove unnecessary instances
  xen/x86: Drop mode-selecting ifdefs in startup_xen()
  xen/x86: Zero out .bss for PV guests
  hvc_xen: make early_printk work with HVM guests
  hvc_xen: fix xenboot for DomUs
  hvc_xen: add earlycon support
2016-03-22 12:55:17 -07:00
Maciej S. Szmigiero a95fc9c8e5 serial: 8250: describe CONFIG_SERIAL_8250_RSA
CONFIG_SERIAL_8250_RSA has waited for a long
time to have meaningful help text so let's
finally describe what this option actually does.

Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Youngmin Nam aba06e9222 serial: samsung: optimize UART rx fifo access routine
This patch optimizes UART rx fifo access routine by reading UART SFR
when necessary. At first, the "fifocnt" variable will be initialized
as Rx FIFO count. So we don't need to access UFSTAT(FIFO status) register
every time to check FIFO count because we know that count with "fifocnt".
After all data were read out from Rx FIFO, the "fifocnt" will be set as 0.
Lastly, UFSTAT will be accessed again to check whether the data remains
by any chance.

Signed-off-by: Youngmin Nam <ym0914@gmail.com>
Reviewed-by: Jung-Ick Guack <ji.guack@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Ed Spiridonov bb70002cb7 serial: pl011: add mark/space parity support
PL011 UART has hardware mark/space parity ability, this trivial patch adds support for it.
Tested on Raspberry Pi v1, v2 (BCM2835 and BCM2836)

Signed-off-by: Ed Spiridonov <edo.rus@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Mathieu OTHACEHE c216c4ad59 tty: serial: 8250: add MOXA Smartio MUE boards support
Add support for :

- CP-102E: 2 ports RS232 PCIE card
- CP-102EL: 2 ports RS232 PCIE card
- CP-132EL: 2 ports RS422/485 PCIE card
- CP-114EL: 4 ports RS232/422/485 PCIE card
- CP-104EL-A: 4 ports RS232 PCIE card
- CP-168EL-A: 8 ports RS232 PCIE card
- CP-118EL-A: 8 ports RS232/422/485 PCIE card
- CP-118E-A: 8 ports RS422/485 PCIE card
- CP-138E-A: 8 ports RS422/485 PCIE card
- CP-134EL-A: 4 ports RS422/485 PCIE card
- CP-116E-A (A): 8 ports RS232/422/485 PCIE card
- CP-116E-A (B): 8 ports RS232/422/485 PCIE card

This patch is based on information extracted from
vendor mxupcie driver available on MOXA website.

I was able to test it on a CP-168EL-A on PC.

Signed-off-by: Mathieu OTHACEHE <m.othacehe@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Andy Shevchenko 013e3586d8 serial: 8250: convert drivers to use up_to_u8250p()
up_to_u8250p() casts struct uart_port * to struct uart_8250_port *. Update code
to use it instead of open coded variant.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Arnd Bergmann 3f5921a60f serial: 8250/mediatek: fix building with SERIAL_8250=m
The Mediatek 8250 driver has a 'bool' Kconfig symbol, but that
breaks when SERIAL_8250 is a loadable module:

drivers/tty/built-in.o: In function `mtk8250_set_termios':
:(.text+0x1bee8): undefined reference to `serial8250_do_set_termios'
:(.text+0x1bf10): undefined reference to `uart_get_baud_rate'
:(.text+0x1c09c): undefined reference to `uart_get_divisor'
drivers/tty/built-in.o: In function `mtk8250_do_pm':
:(.text+0x1c0d0): undefined reference to `serial8250_do_pm'
drivers/tty/built-in.o: In function `mtk8250_probe':
:(.text+0x1c2e4): undefined reference to `serial8250_register_8250_port'
serial/8250/8250_mtk.c:287:242: error: data definition has no type or storage class [-Werror]
serial/8250/8250_mtk.c:287:122: error: 'mtk8250_platform_driver_init' defined but not used [-Werror=unused-function]

This changes the symbol to a 'tristate', so the dependency on
SERIAL_8250 also works when that is set to 'm'.
To actually build the driver, we also need to include <linux/module.h>.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Arnd Bergmann 7d774fb8ca serial: 8250/ingenic: fix building with SERIAL_8250=m
The Ingenic 8250 driver has a 'bool' Kconfig symbol, but that
breaks when SERIAL_8250 is a loadable module:

drivers/tty/built-in.o: In function `ingenic_uart_probe':
8250_ingenic.c:(.text+0x1c1a0): undefined reference to `serial8250_register_8250_port'

This changes the symbol to a 'tristate', plus a dependency on
SERIAL_8250, which makes it work again. Unlike the other
soc-specific backends, this one has no dependency on an
architecture or a platform. I'm adding a dependency on
MIPS || COMPILE_TEST as well here, to avoid showing the driver
on architectures that are not interested in it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Arnd Bergmann a2d3ea2f23 serial: 8250/uniphier: fix modular build
The newly added uniphier serial port driver fails to build as
a loadable module when the base 8250 driver is built-in and
its console support enabled:

ERROR: "early_serial8250_setup" [drivers/tty/serial/8250/8250_uniphier.ko] undefined!

This changes the driver to only provide the early console support
if it is built-in itself as well.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Arnd Bergmann 49c56bfcb7 Revert "drivers/tty/serial: make 8250/8250_ingenic.c explicitly non-modular"
This reverts commit cafe1ac640  ("drivers/tty: make serial
8250_ingenic.c explicitly non-modular"), which attempted to remove dead
code but did not have the desired effect when the main 8250 driver was
a loadable module itself.

This would normally result in a link error, but as the entire
drivers/tty/serial/8250/ directory is only entered when CONFIG_SERIAL_8250
is set, we never notice that the driver does not get built in this
configuration.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Arnd Bergmann 88725e917d Revert "drivers/tty/serial: make 8250/8250_mtk.c explicitly non-modular"
This reverts commit d72d391c12 ("drivers/tty/serial: make
8250/8250_mtk.c explicitly non-modular"), which intended to remove dead
code but did not have the desired effect when the main 8250 driver was
a module itself.

This would normally result in a link error, but as the entire
drivers/tty/serial/8250/ directory is only entered when CONFIG_SERIAL_8250
is set, we never notice that the driver does not get built in this
configuration.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Wilson Ding 30530791a7 serial: mvebu-uart: initial support for Armada-3700 serial port
Armada-3700's uart is a simple serial port, which doesn't
support. Configuring the modem control lines. The uart port has a 32
bytes Tx FIFO and a 64 bytes Rx FIFO

The uart driver implements the uart core operations. It also support the
system (early) console based on Armada-3700's serial port.

Known Issue:

The uart driver currently doesn't support clock programming, which means
the baud-rate stays with the default value configured by the bootloader
at boot time

[gregory.clement@free-electrons.com: Rewrite many part which are too long
to enumerate]

Signed-off-by: Wilson Ding <dingwei@marvell.com>
Signed-off-by: Nadav Haklai <nadavh@marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Romain Izard 82a3f87f6e serial: mctrl_gpio: Add missing module license
As the mctrl_gpio driver can be built as a module, it needs to have its
license specified with MODULE_LICENSE. Otherwise, it cannot access
required symbols exported through EXPORT_SYMBOL_GPL.

Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Arnd Bergmann 0b8053fef6 serial: ifx6x60: avoid uninitialized variable use
gcc warns about a potential use of an uninitialized variable in this driver:

drivers/tty/serial/ifx6x60.c: In function 'ifx_spi_complete':
drivers/tty/serial/ifx6x60.c:713:6: warning: 'more' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if (more || ifx_dev->spi_more || queue_length > 0 ||

Unlike a lot of other such warnings, this one is correct and describes
an actual problem in the handling of the "IFX_SPI_HEADER_F" result code.

This appears to be a result from a restructuring of the driver that
dates back to before it was merged in the kernel, so it's impossible
to know where it went wrong. I also don't know what that result code
means, so I have no idea if setting 'more' to zero is the correct
solution, but at least it makes the behavior reproducible rather than
depending on whatever happens to be on the kernel stack.

This patch initializes the 'more' variable to zero in each of the
three code paths that could result in undefined behavior before,
which is more explicit than initializing it at the start of the
function.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Ludovic Desroches 2958ccee36 tty/serial: at91: fix bad offset for UART timeout register
With SAMA5D2, the UART has hw timeout but the offset of the register to
define this value is not the same as the one for USART.
When using the new UART, the value of this register was 0 so we never
get timeout irqs. It involves that when using DMA, we were stuck until
the execution of the dma callback which happens when a buffer is full
(so after receiving 2048 bytes).

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Romain Izard f4a8ab04dd tty/serial: at91: restore dynamic driver binding
In commit c39dfebc77, the modular support
code for atmel_serial was removed, as the driver cannot be built as a
module. Because no use case was proposed, the dynamic driver binding
support was removed as well.

The atmel_serial driver can manage up to 7 serial controllers, which are
multiplexed with other functions. For example, in the Atmel SAMA5D2, the
Flexcom controllers can work as USART, SPI or I2C controllers, and on
all Atmel devices serial lines can be reconfigured as GPIOs.

My use case uses GPIOs to transfer a firmware update using a custom
protocol on the lines used as a serial port during the normal life of
the device. If it is not possible to unbind the atmel_serial driver, the
GPIO lines remain reserved and prevent this case from working.

This patch reinstates the atmel_serial_remove function, and fixes it as
it failed to clear the "clk" field on removal, triggering an oops when
a device was bound again after being unbound.

Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Jean Delvare 8d2acdb9fc serial: 8250: Add hardware dependency to RT288X option
Kconfig option SERIAL_8250_RT288X seems to be only relevant on MIPS
platforms, so do not present it on other architectures, unless
build-testing.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Mans Rullgard <mans@mansr.com>
Cc: Jiri Slaby <jslaby@suse.com>
Acked-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Greg Hackmann 465893e188 tty: goldfish: support platform_device with id -1
When the platform bus sets the platform_device id to -1 (PLATFORM_DEVID_NONE),
use an incrementing counter for the TTY index instead

Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Miodrag Dinic 9b883eea26 drivers: tty: goldfish: Add device tree bindings
Enable support for registering this device using the device tree.
Device tree node example for registering Goldfish TTY device :

goldfish_tty@1f004000 {
    interrupts = <0xc>;
    reg = <0x1f004000 0x1000>;
    compatible = "google,goldfish-tty";
};

Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Alan <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Maarten Brock 106020ccee serial-uartlite: Configure for rising edge irq trigger.
This device generates a short rising pulse on the interrupt request line.

Signed-off-by: Maarten Brock <m.brock@vanmierlo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Maarten Brock 19606eaf0b serial-uartlite: Spinlock inside the loop.
Better to hold the spinlock as short as possible.

Signed-off-by: Maarten Brock <m.brock@vanmierlo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Maarten Brock 2905697a82 serial-uartlite: Constify uartlite_be/uartlite_le
Made uartlite_be and uartlite_le constants.

Signed-off-by: Maarten Brock <m.brock@vanmierlo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Maarten Brock acf5e6c889 serial-uartlite: Enlarge maximum nr of devices to 16.
This device is ideal to use when you need a lot of uarts in your FPGA.
Try not to force all those users to patch their kernel.

Signed-off-by: Maarten Brock <m.brock@vanmierlo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Andy Shevchenko e78240152b serial: 8250_pci: all known Braswell ports are 1 channel
There is no need to have channel offset defined since all BayTrail and Braswell
ports are 1 channel. Remove unneeded definition.

While here, remove comment which has no value.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Andy Shevchenko 3f64b1d327 serial: 8250_pci: convert to pcim_*() API
The managed API provides a better approach to help with acquiring and releasing
resources. Besides that error handling becomes simpler.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Andy Shevchenko 31f28cc2a2 serial: 8250_dw: remove leftover definitions
The clocks are managed through clk-fractional-divider.c module, and thus CLK
framework takes care about it. Remove letfovers from this driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Andy Shevchenko 34eefb595c serial: 8250_dw: remove redundant 'else' keyword
When the main branch contains return statement the 'else' keyword is not
needed. Remove it here.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Michal Simek 93d7bbaa65 serial: xuartps: Enable OF earlycon support
Support early console setup via DT for all listed compatible strings.
Remove EARLYCON_DECLARE which was done by:
"Use common framework for earlycon declarations"
(sha1: 2eaa790989)
when OF_EARLYCON_DECLARE is defined.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Simon Horman 27202f2f1d tty: sh-sci: Use ARCH_RENESAS
Make use of ARCH_RENESAS in place of ARCH_SHMOBILE.

This is part of an ongoing process to migrate from ARCH_SHMOBILE to
ARCH_RENESAS the motivation for which being that RENESAS seems to be a more
appropriate name than SHMOBILE for the majority of Renesas ARM based SoCs.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Geert Uytterhoeven 9a7a6eb645 serial: sh-sci: Remove redundant instances of EARLYCON_DECLARE()
As of commit 2eaa790989 ("earlycon: Use common framework for
earlycon declarations") it is no longer needer to specify both
EARLYCON_DECLARE() and OF_EARLYCON_DECLARE().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Robin Murphy d9e105ca60 tty: amba-pl011: don't dereference NULL platform data
When only a TX DMA channel is specified in DT, pl011_dma_probe() falls
back to looking for the optional RX channel in platform data. What it
doesn't do is check whether that platform data actually exists...

Add the missing check to avoid crashing the kernel.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Matwey V. Kornilov b18a183eaa tty: serial: Use GFP_ATOMIC instead of GFP_KERNEL in serial8250_em485_init()
serial8250_em485_init() is supposed to be protected with
p->port.lock spinlock.
This may lead to issues when kmalloc sleeps, so it is better to use
GFP_ATOMIC in this spinlocked context.

Fixes: e490c9144c ("tty: Add software emulated RS485 support for 8250")
Reported-by: Ильяс Гасанов <torso.nafi@gmail.com>
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Matwey V. Kornilov bf2a0be45f tty: serial: 8250: Cleanup p->em485 in serial8250_unregister_port
Formally, currently there is no memory leak, but if
serial8250_ports[line] is reused with other 8250 driver, then em485
will be already activated and it will cause issues.

Fixes: e490c9144c ("tty: Add software emulated RS485 support for 8250")
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Sudip Mukherjee 54555919e8 tty: audit: remove unused variable
While building with W=1 we were getting build warning:
drivers/tty/tty_audit.c:149:16: warning: variable 'sessionid' set but not used

The local variable sessionid was only assigned the value of
current->sessionid but was never reused. On further inspection it turned
out that there is no need of audit_get_loginuid() also.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 16:11:14 -08:00
Greg Kroah-Hartman 5f5357335e Revert "sc16is7xx: implemented get_mctrl"
This reverts commit a3f0b77f36.

Maarten writes:
	It appears to be wrong and I don't have a good idea how to fix
	it yet.

Cc: Maarten Brock <m.brock@vanmierlo.com>
Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
2016-03-07 16:10:08 -08:00
Stefano Stabellini a4d7b75be0 hvc_xen: make early_printk work with HVM guests
Refactor the existing code in xen_raw_console_write to get the generic
early_printk console work with HVM guests.

Take the opportunity to replace the outb loop with a single outsb call
to reduce the number of vmexit.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2016-02-26 16:51:24 +00:00
Stefano Stabellini 5de738b3fb hvc_xen: fix xenboot for DomUs
The xenboot early console has been partially broken for DomU for a long
time: the output would only go to the hypervisor via hypercall
(HYPERVISOR_console_io), while it wouldn't actually go to the DomU
console. The reason is that domU_write_console would return early as no
xencons structs are configured for it.

Add an appropriate xencons struct for xenboot from the xenboot setup
callback.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2016-02-26 16:51:08 +00:00
Stefano Stabellini 16e506efc0 hvc_xen: add earlycon support
Introduce EARLYCON support in hvc_xen, useful for early debugging on arm
and arm64, where xen early_printk is not available.

It is different from xenboot_write_console on x86 in two ways:

- it does not return if !xen_pv_domain(), not only because ARM guests
  are xen_hvm_domain(), but also because we want to capture all the
  early boot messages, before xen support is discovered
- it does not try to print to the domU console at all, because xen
  support will only be discovered at a later point

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2016-02-26 15:37:24 +00:00
Maarten Brock a3f0b77f36 sc16is7xx: implemented get_mctrl
Add support for manual getting the modem control lines.

Signed-off-by: Maarten Brock <m.brock@vanmierlo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-14 17:39:36 -08:00
Maarten Brock b7dfdea859 sc16is7xx: implemented set_mctrl
Add support for manual setting the modem control lines.

Signed-off-by: Maarten Brock <m.brock@vanmierlo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-14 17:39:36 -08:00
Guenter Roeck dd9b55883e tty/serial: digicolor: Fix bad usage of IS_ERR_VALUE
IS_ERR_VALUE() assumes that its parameter is an unsigned long.
It can not be used to check if an unsigned int reflects an error.
Doing so can result in the following build warning.

drivers/tty/serial/digicolor-usart.c: In function ‘digicolor_uart_probe’:
include/linux/err.h:21:38: warning:
	comparison is always false due to limited range of data type
drivers/tty/serial/digicolor-usart.c:485:6: note:
	in expansion of macro ‘IS_ERR_VALUE’

If that warning is seen, an error return from platform_get_irq() is missed.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-14 17:39:36 -08:00
Guenter Roeck 8f5405c9f2 serial: clps711x: Fix bad usage of IS_ERR_VALUE
IS_ERR_VALUE() assumes that its parameter is an unsigned long.
It can not be used to check if an unsigned int reflects an error.
Doing so can result in the following build warning.

drivers/tty/serial/clps711x.c: In function ‘uart_clps711x_probe’:
include/linux/err.h:21:38: warning:
	comparison is always false due to limited range of data type
drivers/tty/serial/clps711x.c:471:6: note: in expansion of macro ‘IS_ERR_VALUE’

If that warning is seen, an error return from platform_get_irq() is missed.

Use a temporary variable to check for errors from platform_get_irq().
Also don't use IS_ERR_VALUE() to check if an integer variable is < 0.
The variable can be checked directly in that case.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-14 17:39:36 -08:00