For serial core operations not already excluded by holding port->mutex,
use reference counting to protect deferencing the state->uart_port.
Introduce helper functions, uart_port_ref() and uart_port_deref(), to
wrap uart_port access, and helper macros, uart_port_lock() and
uart_port_unlock(), to wrap combination uart_port access with uart
port lock sections.
Port removal in uart_remove_one_port() waits for reference count to
drop to zero before detaching the uart port from struct uart_state.
For functions only reading the tx circular buffer indexes (where the
uart port lock is claimed to prevent concurrent users), a NULL uart
port is simply ignored and the operation completes normally.
For functions change the tx circular buffer indexes (where the uart
port lock is claimed to prevent concurrent users), the operation is
aborted if the uart port is NULL (ie., has been detached).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_remove_one_port() may race with every serial core operation
requiring a valid dereference of state->uart_port. In particular,
uart_remove_one_port() may unlink the uart port concurrently with
any serial core operation that may dereference same.
Ensure safe dereference for those operations that already claim
the port->mutex, and extend that guarantee for trivial cases,
such as the ioctl handlers. Introduce the uart_port_check() helper
which asserts port->mutex is held (only when lockdep is on).
For ioctls, return -EIO as if the port has been hung up (since it has).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Prepare uart_poll_init() to safely dereference uart port; expand the
port mutex section to guarantee uart port remains valid until
uart_poll_init() completes.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ASYNC*_SHARE_IRQ is no longer used; remove.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace ASYNC_INITIALIZED bit in the tty_port::flags field with
TTY_PORT_INITIALIZED bit in the tty_port::iflags field. Introduce helpers
tty_port_set_initialized() and tty_port_initialized() to abstract
atomic bit ops.
Note: the transforms for test_and_set_bit() and test_and_clear_bit()
are unnecessary as the state transitions are already mutually exclusive;
the tty lock prevents concurrent open/close/hangup.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace ASYNC_SUSPENDED bit in the tty_port::flags field with
TTY_PORT_SUSPENDED bit in the tty_port::iflags field. Introduce helpers
tty_port_set_suspended() and tty_port_suspended() to abstract
atomic bit ops.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace ASYNC_CHECK_CD bit in the tty_port::flags field with
TTY_PORT_CHECK_CD bit in the tty_port::iflags field. Introduce helpers
tty_port_set_check_carrier() and tty_port_check_carrier() to abstract
the atomic bit ops.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace ASYNC_NORMAL_ACTIVE bit in the tty_port::flags field with
TTY_PORT_ACTIVE bit in the tty_port::iflags field. Introduce helpers
tty_port_set_active() and tty_port_active() to abstract atomic bit ops.
Extract state changes from port lock sections, as this usage is
broken and confused; the state transitions are protected by the
tty lock (which mutually excludes parallel open/close/hangup),
and no user tests the active state while holding the port lock.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace ASYNC_CTS_FLOW bit in the tty_port::flags field with
TTY_PORT_CTS_FLOW bit in the tty_port::iflags field. Add
tty_port_set_cts_flow() helper to abstract the atomic bit ops.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Abstract TTY_THROTTLED bit tests with tty_throttled().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Abstract TTY_IO_ERROR status test treewide with tty_io_error().
NB: tty->flags uses atomic bit ops; replace non-atomic bit test
with test_bit().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Version 2 of the Server Base System Architecture (SBSAv2) describes UART
hardware registers as 32 bits wide, giving no guidance on access sizes. The
SBSA UART driver previously assumed partial-length 16 and 8 bit accesses would
work. But the SBSAv2 UART hardware on the Qualcomm Technologies QDF2432 only
supports full-length 32 bit register accesses, so use those exclusively. This
is compatible with SBSAv3, which explicitly requires UART hardware support 32
(and 16 and sometimes 8) bit accesses.
Tested on Juno, Midway, QDF2432, Seattle, and X-Gene 1.
Tested-by: Mark Langsdorf <mlangsdo@redhat.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 1cf6e8fc83 ("tty/serial: at91: fix RTS line management when
hardware handshake is enabled") actually allowed to enable hardware
handshaking.
Before, the CRTSCTS flags was silently ignored.
As the DMA controller can't drive RTS (as explain in the commit message).
Ensure that hardware flow control stays disabled when DMA is used and FIFOs
are not available.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Fixes: 1cf6e8fc83 ("tty/serial: at91: fix RTS line management when hardware handshake is enabled")
Cc: stable <stable@vger.kernel.org> # v4.0+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Dmitry reported, that the current cleanup code in n_gsm can trigger a
warning:
WARNING: CPU: 2 PID: 24238 at drivers/tty/n_gsm.c:2048 gsm_cleanup_mux+0x166/0x6b0()
...
Call Trace:
...
[<ffffffff81247ab9>] warn_slowpath_null+0x29/0x30 kernel/panic.c:490
[<ffffffff828d0456>] gsm_cleanup_mux+0x166/0x6b0 drivers/tty/n_gsm.c:2048
[<ffffffff828d4d87>] gsmld_open+0x5b7/0x7a0 drivers/tty/n_gsm.c:2386
[<ffffffff828b9078>] tty_ldisc_open.isra.2+0x78/0xd0 drivers/tty/tty_ldisc.c:447
[<ffffffff828b973a>] tty_set_ldisc+0x1ca/0xa70 drivers/tty/tty_ldisc.c:567
[< inline >] tiocsetd drivers/tty/tty_io.c:2650
[<ffffffff828a14ea>] tty_ioctl+0xb2a/0x2140 drivers/tty/tty_io.c:2883
...
But this is a legal path when open fails to find a space in the
gsm_mux array and tries to clean up. So make it a standard test
instead of a warning.
Reported-by: "Dmitry Vyukov" <dvyukov@google.com>
Cc: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/r/CACT4Y+bHQbAB68VFi7Romcs-Z9ZW3kQRvcq+BvHH1oa5NcAdLA@mail.gmail.com
Fixes: 5a640967 ("tty/n_gsm.c: fix a memory leak in gsmld_open()")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 21947ba654 ("serial: 8250_pci: replace switch-case by
formula"), the 8250 driver crashes in the byt_set_termios() function
with a divide error. This is caused by the fact that a baud rate of 0 (B0)
is not handled properly. Fix it by falling back to B9600 in this case.
Signed-off-by: David Müller <d.mueller@elsoft.ch>
Fixes: 21947ba654 ("serial: 8250_pci: replace switch-case by formula")
Cc: stable@vger.kernel.org
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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"
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
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>
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>
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>
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>
- 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
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
