Partially reverts 1776fd059c
that introduced regression reported by Paul Walmsley.
This commit restores setting granularity in SCR register
and adds note about comments below being inconsistent with
actual code.
Signed-off-by: Alexey Pelykh <alexey.pelykh@gmail.com>
Tested-by: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some devices have too few buttons, which it makes it hard to have
a reset combo that won't trigger automatically. As such a
timeout functionality that requires the combination to be held for
a given amount of time before triggering is introduced.
If a key combo is recognized and held for a 'timeout' amount of time,
the system triggers a reset. If the timeout value is omitted the
driver simply ignores the functionality.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
In DMA support, The received data is not pushed to tty until the DMA buffer
is filled. But some megabyte rate chips such as BT expect fast response and
data should be pushed immediately. In order to fix this issue, We suggest
the use of the timer for polling DMA buffer.
In our test, no data loss occurred at high-baudrate as compared with interrupt-
driven (We tested with 3Mbps).
We changes:
- We add timer for polling. If we set poll_timer to 10, every 10ms,
timer handler checks the residue in the dma buffer and transfer data
to the tty. Also, last_residue is updated for the next polling.
- poll_timeout is used to prevent the timer's system cost.
If poll_timeout is set to 3000 and no data is received in 3 seconds,
we inactivate poll timer and driver falls back to interrupt-driven.
When data is received again in FIFO and UART irq is occurred, we switch
back to DMA mode and start polling.
- We use consistent DMA mappings to avoid from the frequent cache operation
of the timer function for default.
- pl011_dma_rx_chars is modified. the pending size is recalculated because
data can be taken by polling.
- the polling time is adjusted if dma rx poll is enabled but no rate is
specified. Ideal polling interval to push 1 character at every interval
is the reciprocal of 'baud rate / 10 line bits per character / 1000 ms
per sec'. But It is very aggressive to system. Experimentally,
'10000000 / baud' is suitable to receive dozens of characters. the poll rate
can be specified statically by dma_rx_poll_rate of the platform data as well.
Changes compared to v1:
- Use of consistent DMA mappings.
- Added dma_rx_poll_rate in platform data to specify the polling interval.
- Added dma_rx_poll_timeout in platform data to specify the polling timeout.
Changes compared to v2:
- Use of consistent DMA mappings for default.
- Added dma_rx_poll_enable in platform data to adjust the polling time
according to the baud rate.
- remove unnecessary lock from the polling function.
Signed-off-by: Chanho Min <chanho.min@lge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The no_console_suspend option allows the console to write to the UART
during early resume, before the serial port itself is resumed. Such
writes hang indefinitely waiting for TX ready.
This adds a check to the console putchar function to drop characters
instead of hanging if the port hasn't been initialized. That way, we
can use no_console_suspend without risk of hanging.
Signed-off-by: Michael Spang <spang@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This closes a window where the system may hang in resume as soon as the
UART interrupt is enabled and before the mask is restored. The hang occurs
because the driver can't handle IRQs it thinks are masked.
Signed-off-by: Michael Spang <spang@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the interrupt mask register is not preserved across system suspend
and it defaults to all interrupts enabled, it is not enough to disable
UART interrupt.
This patch adds free_irq to port shutdown and mask setting to port
startup to handle IRQ disabling in a suspend-friendly way. In addition,
a bug caused by multiple request_irq calls in port startup callback is
fixed.
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull TTY/serial fixes from Greg Kroah-Hartman:
"Here are some tty/serial driver fixes for 3.9.
The big thing here is the fix for the huge mess we caused renaming the
8250 driver accidentally in the 3.7 kernel release, without realizing
that there were users of the module options that suddenly broke. This
is now resolved, and, to top the injury off, we have a backwards-
compatible option for those users who got used to the new name since
3.7. Ugh, sorry about that.
Other than that, some other minor fixes for issues that have been
reported by users."
* tag 'tty-3.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
Xilinx: ARM: UART: clear pending irqs before enabling irqs
TTY: 8250, deprecated 8250_core.* options
TTY: 8250, revert module name change
serial: 8250_pci: Add WCH CH352 quirk to avoid Xscale detection
tty: atmel_serial_probe(): index of atmel_ports[] fix
Consider a situation where I have an ARM based system
and therefore no legacy ports. Say, I have two
memory-mapped ports. I use device tree to describe the
ports. What would be the config options I set so that
I get only the two ports in my system? I do not want
legacy ports being created automatically and I want
it to be flexible enough that it creates the devices
based only on the device tree. I expected setting
SERIAL_8250_RUNTIME_UARTS = 0 to work because the
description said, "Set this to the maximum number of
serial ports you want the kernel to register at boot
time." Unfortunately, even though SERIAL_8250_NR_UARTS
was set to the default value of 4, I did not get any device
nodes (because SERIAL_8250_RUNTIME_UARTS was 0). This
is what this change is addressing.
SERIAL_8250_NR_UARTS controls the maximum number of ports
you can support. SERIAL_8250_RUNTIME_UARTS specifies the
number of ports you want to create automatically for legacy
ports at boot time. All other ports will be created
when serial8250_register_port is called (and if does not exceed
the total number of supported ports as specified by
SERIAL_8250_NR_UARTS).
Signed-off-by: Karthik Manamcheri <karthik.manamcheri@ni.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull vfs fixes from Al Viro:
"stable fodder; assorted deadlock fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vt: synchronize_rcu() under spinlock is not nice...
Nest rename_lock inside vfsmount_lock
Don't bother with redoing rw_verify_area() from default_file_splice_from()
vcs_poll_data_free() calls unregister_vt_notifier(), which calls
atomic_notifier_chain_unregister(), which calls synchronize_rcu().
Do it *after* we'd dropped ->f_lock.
Cc: stable@vger.kernel.org (all kernels since 2.6.37)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Mark writes:
ASoC/extcon: arizona: Fix interaction between HPDET and headphone outputs
This patch series covers both ASoC and extcon subsystems and fixes an
interaction between the HPDET function and the headphone outputs - we
really shouldn't run HPDET while the headphone is active. The first
patch is a refactoring to make the extcon side easier.
Support for the WindRiver SBC8560 board was removed in v3.6. But there
are still a few lines depending on its obsolete Kconfig macro. Remove
these now.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Automatic Flow Control capability is not tied to this
property. This is only one way of detecting it. The property
is limited to be used only with 8250 driver.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Boot ROM has an issue which will cause the driver to
lock up as pending irqs are not being cleared. With them
cleared it prevents that issue.
This patch is needed for the current (3.9-rc3) mainline kernel. I guess
it went unnoticed, because it was only tested with u-boot up until now.
And u-boot maybe handles this.
[s.trumtrar@pengutronix.de: cherry-picked from linux-xlnx.git]
Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
They were introduced by mistake in 3.7. Let's deprecate them now. For
the reasons, see the text in Kconfig below.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Josh Boyer <jwboyer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In 3.7 the 8250 module name was changed unintentionally from 8250 to
8250_core by commit 835d844d1a
(8250_pnp: do pnp probe before legacy probe). We then had to
re-introduce the old module options to ensure the old good
8250.nr_uart & co. still work. This can be done only by a very dirty
hack and we did it in f2b8dfd9e4
(serial: 8250: Keep 8250.<xxxx> module options functional after driver
rename).
That is so damn ugly so that I decided to revert to the old module
name and deprecate the new 8250_core options present in 3.7 and 3.8
only. The deprecation will happen in the following patch.
Note that this patch changes the hack above to support "8250_core.*",
because we now have "8250.*" natively.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Josh Boyer <jwboyer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Support for SH7367 and SH7377 got removed in v3.8. Now remove their
last Kconfig macros.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In most cases the tx_loadsz is the same as fifosize. This
will store the fifosize in it if it was not separately
delivered from the driver.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>