Here's the big TTY/serial driver pull request for the 3.5-rc1 merge window.
Nothing major in here, just lots of incremental changes from Alan and
Jiri reworking some tty core things to behave better and to get a more
solid grasp on some of the nasty tty locking issues.
There are a few tty and serial driver updates in here as well.
All of this has been in the linux-next releases for a while with no problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull TTY updates from Greg Kroah-Hartman:
"Here's the big TTY/serial driver pull request for the 3.5-rc1 merge
window.
Nothing major in here, just lots of incremental changes from Alan and
Jiri reworking some tty core things to behave better and to get a more
solid grasp on some of the nasty tty locking issues.
There are a few tty and serial driver updates in here as well.
All of this has been in the linux-next releases for a while with no
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (115 commits)
serial: bfin_uart: Make MMR access compatible with 32 bits bf609 style controller.
serial: bfin_uart: RTS and CTS MMRs can be either 16-bit width or 32-bit width.
serial: bfin_uart: narrow the reboot condition in DMA tx interrupt
serial: bfin_uart: Adapt bf5xx serial driver to bf60x serial4 controller.
Revert "serial_core: Update buffer overrun statistics."
tty: hvc_xen: NULL dereference on allocation failure
tty: Fix LED error return
tty: Allow uart_register/unregister/register
tty: move global ldisc idle waitqueue to the individual ldisc
serial8250-em: Add DT support
serial8250-em: clk_get() IS_ERR() error handling fix
serial_core: Update buffer overrun statistics.
tty: drop the pty lock during hangup
cris: fix missing tty arg in wait_event_interruptible_tty call
tty/amiserial: Add missing argument for tty_unlock()
tty_lock: Localise the lock
pty: Lock the devpts bits privately
tty_lock: undo the old tty_lock use on the ctty
serial8250-em: Emma Mobile UART driver V2
Add missing call to uart_update_timeout()
...
Problem Observed:
- interrupt status is set by rising or falling edge on CTS line
- interrupt status is cleared on a .0. to .1. transition of the
interrupt-clear register bit 1.
- interrupt-clear register is reset by hardware once the interrupt
status is .0..
Remark: It seems not possible to read this register back by the
CPU though, but internally this register exists.
- when simultaneous set and reset event on the interrupt status
happens, then the set-event has priority and the status remains
.1.. As a result the interrupt-clear register is not reset to
.0., and no new .0. to .1. transition can be detected on it when
writing a .1. to it.
This implies race condition, the clear must be performed at least
one UARTCLK the riding edge of CTS RIS interrupt.
Fix:
Instead of resetting UART as done in commit
c16d51a32b
"amba pl011: workaround for uart registers lockup" do the
following:
write .0. and then .1. to the interrupt-clear register to make
sure that this transition is detected. According to the datasheet
writing a .0. does not have any effect, but actually it allows to
reset the internal interrupt-clear register.
Take into account:
The .0. needs to last at least for one clk_uart clock period
(~ 38 MHz, 26.08ns)
This way we can do away with the tasklet and keep only a tiny
fix triggered by the variant flag introduced in this patch.
Signed-off-by: Guillaume Jaunet <guillaume.jaunet@stericsson.com>
Signed-off-by: Christophe Arnal <christophe.arnal@stericsson.com>
Signed-off-by: Matthias Locher <Matthias.Locher@stericsson.com>
Signed-off-by: Rajanikanth H.V <rajanikanth.hv@stericsson.com>
Reviewed-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 360f748b204275229f8398cb2f9f53955db1503b
"serial: PL011: clear pending interrupts"
attempts to clear interrupts by writing to a
yet-unassigned memory address. This fixes the issue.
The breaking patch is marked for stable so should be
carried along with the other patch.
Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: stable <stable@vger.kernel.org>
Cc: Nicolas Pitre <nico@fluxnic.net>
Reported-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull slave-dmaengine update from Vinod Koul:
"This includes the cookie cleanup by Russell, the addition of context
parameter for dmaengine APIs, more arm dmaengine driver cleanup by
moving code to dmaengine, this time for imx by Javier and pl330 by
Boojin along with the usual driver fixes."
Fix up some fairly trivial conflicts with various other cleanups.
* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (67 commits)
dmaengine: imx: fix the build failure on x86_64
dmaengine: i.MX: Fix merge of cookie branch.
dmaengine: i.MX: Add support for interleaved transfers.
dmaengine: imx-dma: use 'dev_dbg' and 'dev_warn' for messages.
dmaengine: imx-dma: remove 'imx_dmav1_baseaddr' and 'dma_clk'.
dmaengine: imx-dma: remove unused arg of imxdma_sg_next.
dmaengine: imx-dma: remove internal structure.
dmaengine: imx-dma: remove 'resbytes' field of 'internal' structure.
dmaengine: imx-dma: remove 'in_use' field of 'internal' structure.
dmaengine: imx-dma: remove sg member from internal structure.
dmaengine: imx-dma: remove 'imxdma_setup_sg_hw' function.
dmaengine: imx-dma: remove 'imxdma_config_channel_hw' function.
dmaengine: imx-dma: remove 'imxdma_setup_mem2mem_hw' function.
dmaengine: imx-dma: remove dma_mode member of internal structure.
dmaengine: imx-dma: remove data member from internal structure.
dmaengine: imx-dma: merge old dma-v1.c with imx-dma.c
dmaengine: at_hdmac: add slave config operation
dmaengine: add context parameter to prep_slave_sg and prep_dma_cyclic
dmaengine/dma_slave: introduce inline wrappers
dma: imx-sdma: Treat firmware messages as warnings instead of erros
...
Add inline wrappers for device_prep_slave_sg() and device_prep_dma_cyclic()
interfaces to hide new parameter from current users of affected interfaces.
Convert current users to use new wrappers instead of direct calls.
Suggested by Russell King [https://lkml.org/lkml/2012/2/3/269].
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Chanho Min reported that when the boot loader transfers
control to the kernel, there may be pending interrupts
causing the UART to lock up in an eternal loop trying to
pick tokens from the FIFO (since the RX interrupt flag
indicates there are tokens) while in practice there are
no tokens - in fact there is only a pending IRQ flag.
This patch address the issue with a combination of two
patches suggested by Russell King that clears and mask
all interrupts at probe() and clears any pending error
and RX interrupts at port startup time.
We suspect the spurious interrupts are a side-effect of
switching the UART from FIFO to non-FIFO mode.
Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Reported-by: Chanho Min <chanho0207@gmail.com>
Suggested-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Jong-Sung Kim <neidhard.kim@lge.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In DMA-operated uart, I found that rx data can be taken by the UART
interrupts during the DMA irq handler. pl011_int is occurred just
before it goes inside spin_lock_irq. When it returns to the callback,
DMA buffer already has been flushed. Then, pl011_dma_rx_chars gets
invalid data. So I add check for the residue as the patch bellow.
Signed-off-by: Chanho Min <chanho.min@lge.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
.device_fc is added in struct dma_slave_config recently. All user drivers, which
want DMA to be the flow controller must pass this field as false. As earlier
driver don't look to use this feature, mark it false for now.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Protect against pl011_console_write() and the interrupt for
the console UART running concurrently on different CPUs.
Otherwise the console_write could spin for a long time
waiting for the UART to become not busy, while the other
CPU continuously services UART interrupts and keeps the
UART busy.
The checks for sysrq and oops_in_progress are taken
from 8250.c.
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Reviewed-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Reviewed-by: Bibek Basu <bibek.basu@stericsson.com>
Reviewed-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>
In present driver, shutdown clears RTS and DTR in CR register. But the
documentation "Documentation/serial/driver" suggests not to disable
RTS and DTR in shutdown(). Also RTS and DTR is preserved between shutdown
and startup calls, i.e. these are restored in startup if they were enabled
while doing shutdown. So that if RTS and DTR are set using pl011_set_mctrl
then it should continue even after shutdown->startup sequence.
For throttling/unthrottling user should call pl011_set_mctrl.
Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
fixup usage of dma direction by introducing dma_transfer_direction,
this patch moves spi, serial drivers to use new enum
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@iki.fi>
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>
remove invalid location line in each file header after location
moved from driver/char to driver/tty
Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This piece of code was just slightly different between the DMA
and IRQ paths, in DMA mode we surely shouldn't read more than
256 character either, so factor this out in its own function and
use for both DMA and PIO mode.
Tested on Ux500 and U300.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This adds an optional RX DMA codepath for the devices that
support this by using the apropriate burst sizes instead of
pulling single bytes.
Includes portions of code written by Russell King during
a PL08x hacking session.
This has been tested on U300 and Ux500.
Tested-by: Jerzy Kasenberg <jerzy.kasenberg@tieto.com>
Tested-by: Grzegorz Sygieda <grzegorz.sygieda@tieto.com>
Tested-by: Marcin Mielczarczyk <marcin.mielczarczyk@tieto.com>
Signed-off-by: Per Forlin <per.friden@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Make Primecell driver probe functions take a const pointer to their
ID tables. Drivers should never modify their ID tables in their
probe handler.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The serial drivers are really just tty drivers, so move them to
drivers/tty/ to make things a bit neater overall.
This is part of the tty/serial driver movement proceedure as proposed by
Arnd Bergmann and approved by everyone involved a number of months ago.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl>
Cc: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Linus Torvalds