| Age | Commit message (Collapse) | Author | Files | Lines |
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Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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In s3c24xx_serial_console_setup function, if the uart port that is
being setup as a console has not been initialized, an error can be
returned instead of using uart port 0 as the default console port.
The uart port that was intended to be used as a console could be
initialized at a later point during boot and then registered as a
console. This will avoid using uart port 0 as a unintended console
port.
Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
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master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
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git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-2.6-arm-soc
* 'at91/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-2.6-arm-soc:
AT91: Change nand buswidth logic to match hardware default configuration
at91: Use "pclk" as con_id on at91cap9 and at91rm9200
at91: fix udc, ehci and mmc clock device name for cap9/9g45/9rl
atmel_serial: fix internal port num
at91: fix at91_set_serial_console: use platform device id
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Simplifies the code a bit and drops a few lines.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Arnd Bergmann <arnd@arndb.de>
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Unthrottling the TTY during close ends up enabling interrupts
on a device not on the active list, which will never have the
interrupts cleared. Doctor, it hurts when I do this.
>>> On 6/2/2011 at 01:56 AM, in message <20110601145608.3e586e16@bob.linux.org.uk>, Alan Cox <alan@linux.intel.com> wrote:
> On Wed, 01 Jun 2011 10:34:07 +1200
> "andrew mcgregor" <andrew.mcgregor@alliedtelesis.co.nz> wrote:
> > The LKML message
> > http://kerneltrap.org/mailarchive/linux-kernel/2010/2/25/4541847 from
> > February doesn't seem to have been resolved since. We struck the
> > issue, and the patch below (against 2.6.32) fixes it. Should I
> > supply a patch against 3.0.0rc?
>
> I think that would be sensible. I don't actually see how you hit it as
> the IRQ ought to be masked by then but it's certainly wrong for n_tty
> to be calling into check_unthrottle at that point.
>
> So yes please send a patch with a suitable Signed-off-by: line to
> linux-serial and cc GregKH <greg@kroah.com> as well.
>
> Alan
Signed-off-by: Andrew McGregor <andrew.mcgregor@alliedtelesis.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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This patch "modernize" tty/serial/samsung.c to use non-legacy code for
suspend/resume.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: KyungMin Park <kyungmin.park@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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Kconfig allows enabling console support for the SC26xx driver even when
it's configured as a module resulting in a:
ERROR: "uart_console_device" [drivers/tty/serial/sc26xx.ko] undefined!
modpost error since the driver was merged in
eea63e0e8a60d00485b47fb6e75d9aa2566b989b [SC26XX: New serial driver for
SC2681 uarts] in 2.6.25. Fixed by only allowing console support to be
enabled if the driver is builtin.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: stable <stable@kernel.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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The driver went to initialize its waitqueue at the start of the main processing
thread. However, it is possible that this thread is not scheduled on a CPU
before the write function is called which leads to a following error:
BUG: spinlock bad magic on CPU#1, swapper/1
lock: f5f3ebdc, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
Pid: 1, comm: swapper Not tainted 3.0.0-rc2+ #67
Call Trace:
[<c1289663>] spin_bug+0xa3/0xf0
[<c12897ad>] do_raw_spin_lock+0x7d/0x150
[<c1490006>] ? init_idle+0x8d/0x20c
[<c14963de>] _raw_spin_lock_irqsave+0x4e/0x60
[<c102f2bb>] ? __wake_up+0x1b/0x50
[<c102f2bb>] __wake_up+0x1b/0x50
[<c12d03bc>] ? uart_console_write+0x4c/0x60
[<c12d36c0>] ? serial_m3110_enable_ms+0x10/0x10
[<c12d3715>] serial_m3110_con_write+0x55/0x60
[<c1041575>] __call_console_drivers+0x75/0x90
[<c10415d9>] _call_console_drivers+0x49/0x80
[<c1041baa>] console_unlock+0xca/0x1f0
[<c10420ef>] vprintk+0x18f/0x4f0
[<c10787cb>] ? trace_hardirqs_on+0xb/0x10
[<c14928a3>] printk+0x18/0x1a
[<c1042730>] register_console+0x2e0/0x350
[<c12d098e>] uart_add_one_port+0x33e/0x3d0
[<c10787cb>] ? trace_hardirqs_on+0xb/0x10
[<c103e10b>] ? try_to_wake_up+0x18b/0x250
[<c1485ba6>] serial_m3110_probe+0x1c2/0x1df
[<c12d3d20>] ? serial_m3110_suspend+0x40/0x40
[<c1303db7>] spi_drv_probe+0x17/0x20
...
We fix this by initializing the waitqueue before the main thread is created.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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Change print message to notice instead of error to clean up
non critcal messages showing on startup. The MAX3111 not being present
is a normal path for end user systems.
Signed-off-by: William Douglas <william.douglas@intel.com>
[rebased on 3.0, switched to dev_dbg()]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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This patch addes delay loop on fifo reset function for UART.
On high speed freq, it needs delay function when fifo reset.
If not, system will hang by this uart reset problem when resuming
from suspend mode.
Signed-off-by: Jongpill Lee <boyko.lee@samsung.com>
Signed-off-by: Jaecheol Lee <jc.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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Commit 4539c24fe4f92c09ee668ef959d3e8180df619b9 "tty/serial: Add
explicit PORT_TEGRA type" introduced separate flags describing the need
for IER bits UUE and RTOIE. Both bits are required for the XSCALE port
type. While that patch updated uart_config[] as required, the auto-probing
code wasn't updated to set the RTOIE flag when an XSCALE port type was
detected. This caused such ports to stop working. This patch rectifies
that.
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Cc: stable <stable@kernel.org> [3.0]
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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This doesn't cause any real bugs, but it should still be fixed.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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Since the printk_ratelimit() shouldn't be used anymore (see comment in
include/linux/printk.h), replace it with printk_ratelimited().
Signed-off-by: Manuel Zerpies <manuel.f.zerpies@ww.stud.uni-erlangen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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The gsm_mux is created/destroyed when ldisc is
opened/closed but clients of the MUX channel devices (gsmttyN)
may access this structure as long as the TTYs are open.
For the open, the ldisc open is guaranteed to preceed the TTY open,
but the close has no such guaranteed ordering. As a result,
the gsm_mux can be freed in the ldisc close before being accessed
by one of the TTY clients. This can happen if the ldisc is removed
while there are open, active MUX channels.
A similar situation exists for DLCI-0, it is basically a resource
shared by MUX and DLCI , and should not be freed while they can
be accessed
To avoid this, gsm_mux and dlcis now have a reference counter
ldisc open takes a reference on the mux and all the dlcis
gsmtty_open takes a reference on the mux, dlci0 and its specific
dlci. Dropping the last reference initiates the actual free.
Signed-off-by: Russ Gorby <russ.gorby@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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This patch adds the ability to open a network data connection over a mux
virtual tty channel. This is for modems that support data connections
with raw IP frames instead of PPP. On high speed data connections this
eliminates a significant amount of PPP overhead. To use this interface,
the application must first tell the modem to open a network connection on
a virtual tty. Once that has been accomplished, the app will issue an
IOCTL on that virtual tty to create the network interface. The IOCTL will
return the index of the interface created.
The two IOCTL commands are:
ioctl( fd, GSMIOC_ENABLE_NET );
ioctl( fd, GSMIOC_DISABLE_NET );
Signed-off-by: Russ Gorby <russ.gorby@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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The n_gsm driver being an ldisc, does not provide a convenient method
e.g. udev to create the tty device nodes automatically when the ldisc
is opened.
The TTY device nodes are now created via calls to tty_register_device
from the ldisc open.
Signed-off-by: Russ Gorby <russ.gorby@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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A mix of think & mismerge on my side caused a problem where both the
new hvsi_lib and the old hvsi driver gets compiled and try to define
symbols with the same name.
This fixes it by renaming the hvsi_lib exported symbols.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Some platforms e.g. TI Davinci require 32-bit accesses to the UARTs.
The of_serial driver currently registers all UARTs as UPIO_MEM. Add a
new attribute "reg-io-width" to allow the port to be registered with
different IO width requirements.
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
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This will allow a different backend to share it
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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On pseries machines, consoles are provided by the hypervisor using
a low level get_chars/put_chars type interface. However, this is
really just a transport to the service processor which implements
them either as "raw" console (networked consoles, HMC, ...) or as
"hvsi" serial ports.
The later is a simple packet protocol on top of the raw character
interface that is supposed to convey additional "serial port" style
semantics. In practice however, all it does is provide a way to
read the CD line and set/clear our DTR line, that's it.
We currently implement the "raw" protocol as an hvc console backend
(/dev/hvcN) and the "hvsi" protocol using a separate tty driver
(/dev/hvsi0).
However this is quite impractical. The arbitrary difference between
the two type of devices has been a major source of user (and distro)
confusion. Additionally, there's an additional mini -hvsi implementation
in the pseries platform code for our low level debug console and early
boot kernel messages, which means code duplication, though that low
level variant is impractical as it's incapable of doing the initial
protocol negociation to establish the link to the FSP.
This essentially replaces the dedicated hvsi driver and the platform
udbg code completely by extending the existing hvc_vio backend used
in "raw" mode so that:
- It now supports HVSI as well
- We add support for hvc backend providing tiocm{get,set}
- It also provides a udbg interface for early debug and boot console
This is overall less code, though this will only be obvious once we
remove the old "hvsi" driver, which is still available for now. When
the old driver is enabled, the new code still kicks in for the low
level udbg console, replacing the old mini implementation in the platform
code, it just doesn't provide the higher level "hvc" interface.
In addition to producing generally simler code, this has several benefits
over our current situation:
- The user/distro only has to deal with /dev/hvcN for the hypervisor
console, avoiding all sort of confusion that has plagued us in the past
- The tty, kernel and low level debug console all use the same code
base which supports the full protocol establishment process, thus the
console is now available much earlier than it used to be with the
old HVSI driver. The kernel console works much earlier and udbg is
available much earlier too. Hackers can enable a hard coded very-early
debug console as well that works with HVSI (previously that was only
supported for the "raw" mode).
I've tried to keep the same semantics as hvsi relative to how I react
to things like CD changes, with some subtle differences though:
- I clear DTR on close if HUPCL is set
- Current hvsi triggers a hangup if it detects a up->down transition
on CD (you can still open a console with CD down). My new implementation
triggers a hangup if the link to the FSP is severed, and severs it upon
detecting a up->down transition on CD.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Embed the struct hvsi_header in the various packet definitions
rather than open coding it multiple times. Will help provide
stronger type checking.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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This moves various HVSI protocol definitions from the hvsi.c
driver to a header file that can be used later on by a udbg
implementation
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6
* 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6:
serial: bcm63xx_uart: fix irq storm after rx fifo overrun.
amba pl011: platform data for reg lockup and glitch v2
amba pl011: workaround for uart registers lockup
tty: n_gsm: improper skb_pull() use was leaking framed data
tty: n_gsm: Fixed logic to decode break signal from modem status
TTY: ntty, add one more sanity check
TTY: ldisc, do not close until there are readers
8250: Fix capabilities when changing the port type
8250_pci: Fix missing const from merges
ARM: SAMSUNG: serial: Fix on handling of one clock source for UART
serial: ioremap warning fix for jsm driver.
8250_pci: add -ENODEV code for Intel EG20T PCH
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Presently these were all using the same static string with no regard to
dev_name() and the like. This implements a bit of rework to name the IRQ
dynamically, as it should have been doing all along anyways.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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Ultimately we want everything to be going through the clock framework and
runtime pm, so kill off the per-port callbacks that enabled ports to
bypass the common infrastructure.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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This was using a BUG_ON(), but it's not strictly necessary, so relax the
constraints a bit.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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Fis the warning
drivers/tty/serial/8250_pci.c:1457: warning: initialization from incompatible pointer type
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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the atmel_ports is link to the console number and not the device id
this was not detected on at91 as we always register the dbgu on the console
as ttyS0
tested on at91sam9263 by setting the dbgu as ttyS1 and use as console
diff --git a/arch/arm/mach-at91/board-sam9263ek.c b/arch/arm/mach-at91/board-sam9263ek.c
index 70e5646..9b8a14f 100644
- a/arch/arm/mach-at91/board-sam9263ek.c
+ b/arch/arm/mach-at91/board-sam9263ek.c
@@ -58,14 +58,14 @@ static void __init ek_init_early(void)
/* Initialize processor: 16.367 MHz crystal */
at91_initialize(16367660);
- /* DBGU on ttyS0. (Rx & Tx only) */
- at91_register_uart(0, 0, 0);
+ /* DBGU on ttyS1. (Rx & Tx only) */
+ at91_register_uart(0, 1, 0);
- /* USART0 on ttyS1. (Rx, Tx, RTS, CTS) */
- at91_register_uart(AT91SAM9263_ID_US0, 1, ATMEL_UART_CTS | ATMEL_UART_RTS);
+ /* USART0 on ttyS0. (Rx, Tx, RTS, CTS) */
+ at91_register_uart(AT91SAM9263_ID_US0, 0, ATMEL_UART_CTS | ATMEL_UART_RTS);
- /* set serial console to ttyS0 (ie, DBGU) */
- at91_set_serial_console(0);
+ /* set serial console to ttyS1 (ie, DBGU) */
+ at91_set_serial_console(1);
}
/*
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
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Just tyops.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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The driver went to initialize its waitqueue at the start of the main
processing thread. However, it is possible that this thread is not
scheduled on a CPU before the write function is called which leads to a
following error:
BUG: spinlock bad magic on CPU#1, swapper/1
lock: f5f3ebdc, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
Pid: 1, comm: swapper Not tainted 3.0.0-rc2+ #67
Call Trace:
[<c1289663>] spin_bug+0xa3/0xf0
[<c12897ad>] do_raw_spin_lock+0x7d/0x150
[<c14963de>] _raw_spin_lock_irqsave+0x4e/0x60
[<c102f2bb>] __wake_up+0x1b/0x50
[<c12d3715>] serial_m3110_con_write+0x55/0x60
[<c1041575>] __call_console_drivers+0x75/0x90
[<c10415d9>] _call_console_drivers+0x49/0x80
[<c1041baa>] console_unlock+0xca/0x1f0
[<c10420ef>] vprintk+0x18f/0x4f0
[<c14928a3>] printk+0x18/0x1a
[<c1042730>] register_console+0x2e0/0x350
[<c12d098e>] uart_add_one_port+0x33e/0x3d0
[<c1485ba6>] serial_m3110_probe+0x1c2/0x1df
[<c1303db7>] spi_drv_probe+0x17/0x20
...
Fix this by initializing the waitqueue before the main thread is
created.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Change print message to notice instead of error to clean up non critical
messages showing on startup. The MAX3111 not being present is a normal
path for end user systems.
Signed-off-by: William Douglas <william.douglas@intel.com>
[rebased on 3.0, switched to dev_dbg()]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Remove linux/mm.h inclusion from netdevice.h -- it's unused (I've checked manually).
To prevent mm.h inclusion via other channels also extract "enum dma_data_direction"
definition into separate header. This tiny piece is what gluing netdevice.h with mm.h
via "netdevice.h => dmaengine.h => dma-mapping.h => scatterlist.h => mm.h".
Removal of mm.h from scatterlist.h was tried and was found not feasible
on most archs, so the link was cutoff earlier.
Hope people are OK with tiny include file.
Note, that mm_types.h is still dragged in, but it is a separate story.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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RX fifo reset is required to clear irq.
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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This workaround aims to break the deadlock situation
which raises during continuous transfer of data for long
duration over uart with hardware flow control. It is
observed that CTS interrupt cannot be cleared in uart
interrupt register (ICR). Hence further transfer over
uart gets blocked.
It is seen that during such deadlock condition ICR
don't get cleared even on multiple write. This leads
pass_counter to decrease and finally reach zero. This
can be taken as trigger point to run this UART_BT_WA.
Workaround backups the register configuration, does soft
reset of UART using BIT-0 of PRCC_K_SOFTRST_SET/CLEAR
registers and restores the registers.
This patch also provides support for uart init and exit
function calls if present.
Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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gsm_dlci_data_output_framed() was doing:
memcpy(dp, skb_pull(dlci->skb, len), len);
The problem is skb_pull() returns the post-increment data ptr
so the first chunk of dlci->skb->data is leaked.
Signed-off-by: Russ Gorby <russ.gorby@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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The modem status can be one or 2 octets and contains the V.24 signals
and in the 2 octet case also the break signal.
We were improperly decoding the break signal from the modem in the
2 octet case.
Signed-off-by: Russ Gorby <russ.gorby@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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If dmi_get_system_info() returns NULL, pch_uart_init_port() will
dereferencea a zero pointer.
This oops was observed on an Atom based board which has no BIOS, but
a bootloder which doesn't provide DMI data.
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Greg KH <gregkh@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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For all ports with a valid SCLSR register we can use the generic FIFO
overrun detection logic. Test the validity of the SCLSR register rather
than depending explicitly on port type, which can be ambiguous for the
SCIFA/B types.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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This consolidates all of the TX/RX fill/room nonsense in to a single set
of fairly heavyweight definitions. The implementation goes in descending
order of complexity, testing the register map for capabilities until we
run out of options and do it the legacy SCI way. Masks are derived
directly from the per-port FIFO size, meaning that platforms with FIFO
sizes not matching the standard port types will still need to manually
fix them up.
This also fixes up a number of issues such as tx_empty being completely
bogus for SCI and IrDA ports, some ports using masks smaller or greater
than their FIFO size, and so forth.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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This takes a bit of a sledgehammer to the horribly CPU subtype
ifdef-ridden header and abstracts all of the different register layouts
in to distinct types which in turn can be overriden on a per-port basis,
or permitted to default to the map matching the port type at probe time.
In the process this ultimately fixes up inumerable bugs with mismatches
on various CPU types (particularly the legacy ones that were obviously
broken years ago and no one noticed) and provides a more tightly coupled
and consolidated platform for extending and implementing generic
features.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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Several fixes as well where the +1 was missing.
Done via coccinelle scripts like:
@@
struct resource *ptr;
@@
- ptr->end - ptr->start + 1
+ resource_size(ptr)
and some grep and typing.
Mostly uncompiled, no cross-compilers.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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The flush_to_ldisc() work entry has special logic to notice when it has
seen the original tail of the data queue, and it avoids continuing the
flush if it sees that _original_ tail rather than the current tail.
This logic can trigger in case somebody is constantly adding new data to
the tty while the flushing is active - and the intent is to avoid
excessive CPU usage while flushing the tty, especially as we used to do
this from a softirq context which made it non-preemptible.
However, since we no longer re-arm the work-queue from within itself
(because that causes other trouble: see commit a5660b41af6a "tty: fix
endless work loop when the buffer fills up"), this just leads to
possible hung tty's (most easily seen in SMP and with a test-program
that floods a pty with data - nobody seems to have reported this for any
real-life situation yet).
And since the workqueue isn't done from timers and softirq's any more,
it's doubtful whether the CPU useage issue is really relevant any more.
So just remove the logic entirely, and see if anybody ever notices.
Alternatively, we might want to re-introduce the "re-arm the work" for
just this case, but then we'd have to re-introduce the delayed work
model or some explicit timer, which really doesn't seem worth it for
this.
Reported-and-tested-by: Guillaume Chazarain <guichaz@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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Non-SCI parts do not have the special port reg necessary for cases where
the RX and SCI pins are muxed and need to be manually polled, so these
like always fall back on the normal FIFO processing paths. SH7760 is in a
class in and of itself with regards to mapping its SIM card interface via
the SCI port class despite not having any of the RXD lines wired up and
so implicitly behaving more like a SCIF in this regard. Out of the other
CPUs, some support the port check via the same block while others do it
through an external SuperI/O, so it's not even possible to perform the
check relative to the ioremapped cookie offset, so the separate read
semantics are preserved here, too.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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