Currently, serial drivers don't report buffer overruns. When a buffer overrun
occurs, tty_insert_flip_char returns 0, and no attempt is made to insert that
same character again (i.e. it is lost). This patch reports buffer overruns via
the buf_overrun field in the port's icount structure.
Signed-off-by: Corbin Atkinson <corbin.atkinson@ni.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In theory we don't need it, in practice we are hitting some ill understood
deadlock when we don't drop it. The old code dropped it here so we are not
undoing anything problematic for pty. If pty could be unloaded it would be
a problem but it can't.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit d29f3ef39b
"tty_lock: Localise the lock"
added a tty arg to wait_event_interruptible_tty() but it missed
this arch specific instance for cris, causing a compile failure.
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d29f3ef39b ("tty_lock: Localise the lock")
missed that d3a7b83f86 ("drivers/tty/amiserial.c:
add missing tty_unlock") just added a new caller of tty_unlock():
drivers/tty/amiserial.c: In function ‘set_serial_info’:
drivers/tty/amiserial.c:1077: error: too few arguments to function ‘tty_unlock’
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In each remaining case the tty_lock is associated with a specific tty. This
means we can now lock on a per tty basis. We do need tty_lock_pair() for
the pty case. Uglier but still a step in the right direction.
[fixed up calls in 3 missing drivers - gregkh]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a private pty affair, we don't want to tangle it with the tty_lock
any more as we know all the other non tty locking is now handled by the vfs
so we too can move.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
get_current_tty has its own consistent locking. That means a pile of the
tty lock cases are not needed. As get_current_tty also keeps a reference the
tty object lifetime means we can propogate the lock removal out.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is V2 of the Emma Mobile 8250 platform driver.
The hardware itself has according to the data sheet
up to 64 byte FIFOs but at this point we only make
use of the 16550 compatible mode.
To support this piece of hardware the common UART
registers need to be remapped, and the access size
differences need to be handled.
The DLL and DLM registers can due to offset collision
not be remapped easily, and because of that this
driver makes use of ->dl_read() and ->dl_write()
callbacks. This in turn requires a registration
function that takes 8250-specific paramenters.
Future potential enhancements include DT support,
early platform driver console and fine grained PM.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Alan Cox <alan@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The variable 'mxser_port_ops' is only referenced in this file and
should be marked static to prevent it from being exposed globally.
Quites the sparse warning:
warning: symbol 'mxser_port_ops' was not declared. Should it be static?
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce yet another 8250 registration function.
This time it is serial8250_register_8250_port() and it
allows us to register 8250 hardware instances using struct
uart_8250_port. The new function makes it possible to
register 8250 hardware that makes use of 8250 specific
callbacks such as ->dl_read() and ->dl_write().
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Get rid of unused functions and macros now when
Alchemy and RM9K are converted over to callbacks.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert the 8250 RM9K support code to make
use of the new dl_read()/dl_write() callbacks.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert the 8250 Alchemy support code to make
use of the new dl_read()/dl_write() callbacks.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert serial_dl_read() and serial_dl_write() from macro
to 8250 specific callbacks. This change makes it easier to
support 8250 hardware with non-standard DLL and DLM register
configurations such as Alchemy, RM9K and upcoming Emma Mobile
UART hardware.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We noticed that we were loosing data at speed less than 2400 baud.
It turned out our (TI16750 compatible) uart with 64 byte outgoing fifo
was truncated to 16 byte (bit 5 sets fifo len) when modifying the fcr
reg.
The input code still fills the buffer with 64 bytes if I remember
correctly and thus data is lost.
Our fix was to remove whiping of the fcr content and just add the
TRIGGER_1 which we want for latency.
I can't see why this would not work on less than 2400 always, for all
uarts ...
Otherwise one would have to make sure the filling of the fifo re-checks
the current state of available fifo size (urrk).
Signed-off-by: Christian Melki <christian.melki@ericsson.se>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The rules used to make 8250_pci "ignore" the PCH uarts are lacking pci subids
entries, preventing it to match and thus is breaking serial port support for
theses systems.
This has been tested on a nanoETXexpress-TT, which has a specifici uart clock.
Tested-by: Erwan Velu <Erwan.Velu@zodiacaerospace.com>
[stable@: please apply to 3.0-stable, 3.2-stable and 3.3-stable]
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Arnaud Patard <apatard@hupstream.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
copy_from_read_buf currently copies data to a user buffer and then
checks if the data is single EOF. But it checks it by accessing the
user buffer. First, the buffer may be changed by other threads of the
user program already. Second, it accesses the buffer without any
checks. It might be write-only for example.
Fix this by inspecting contents of the tty (kernel) buffer instead.
Note that "n == 1" is necessary, but not sufficient. But we check
later that there is nothing left by "!tty->read_cnt" condition.
There is still an issue with the current code that EOF being wrapped
to the start of the circular buffer will result in an inappropriate
losing of the EOF character. But this is not intended to be fixed by
this patch.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: Emil Goode <emilgoode@gmail.com>
Cc: Howard Chu <hyc@symas.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When we do this it becomes clear the lock we should be holding is the vc
lock, and in fact many of our other helpers are properly invoked this way.
We don't at this point guarantee not to race the keyboard code but the results
of that appear harmless and that was true before we started as well.
We now have no users of tty_lock in the console driver...
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_unlock is used on all other exits from the function.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When using Serial Over Lan (SOL) over the virtual serial port in a Intel
management engine (ME) device, on device reset the serial FIFOs need to
be cleared to keep the FIFO indexes in-sync between the host and the
engine.
On a reset the serial device assertes BI, so using that as a cue FIFOs
are cleared. So for this purpose a new handle_break callback has been
added. One other problem is that the serial registers might temporarily
go to 0 on reset of this device. So instead of using the IER register
read, if 0 returned use the ier value in uart_8250_port. This is hidden
under a custom serial_in.
Cc: Nhan H Mai <nhan.h.mai@intel.com>
Signed-off-by: Sudhakar Mamillapalli <sudhakar@fb.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This driver anticipates pch_uart_verify_port() is not called
during installation.
However, actually pch_uart_verify_port() is called during
installation.
As a result, memory access violation occurs like below.
0. initial value: use_dma=0
1. starup()
- dma channel is not allocated because use_dma=0
2. pch_uart_verify_port()
- Set use_dma=1
3. UART processing acts DMA mode because use_dma=1
- memory access violation occurs!
This patch fixes the issue.
Solution:
Whenever pch_uart_verify_port() is called and then
dma channel is not allocated, the channel should be allocated.
Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since 2.6.30-rc1 clps711x serial driver hungs system. This is a result
of call disable_irq from ISR. synchronize_irq waits for end of interrupt
and goes to infinite loop. This patch fix this problem.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "KT" serial port has another use case for a "received break" quirk,
so before adding another special case to the 8250 core take this
opportunity to push such quirks out of the core and into a uart_port op.
Stephen says:
"If the callback function is to no longer live in 8250.c itself,
arch/arm/mach-tegra/devices.c isn't logically a good place to put it,
and that file will be going away once we get rid of all the board files
and move solely to device tree."
...so since 8250_pci.c houses all the quirks for pci serial devices this
quirk is similarly housed in of_serial.c. Once the open firmware
conversion completes the infrastructure details
(include/linux/of_serial.h, and the export) can all be removed to make
this self contained to of_serial.c.
Cc: Nhan H Mai <nhan.h.mai@intel.com>
Cc: Colin Cross <ccross@android.com>
Cc: Olof Johansson <olof@lixom.net>
[stephen: kill CONFIG_SERIAL_TEGRA in favor just using CONFIG_ARCH_TEGRA]
Cc: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sudhakar Mamillapalli <sudhakar@fb.com>
Reported-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently the errata is populated based on cpu checks this can
be removed and replaced with module version check of uart ip block.
MVR reg is provided within the uart reg map use the same
to populate the errata and thus now errata population and handling
can be managed within the driver itself.
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Govindraj.R <govindraj.raja@ti.com>
Reviewed-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
A -next commit "TTY: HVC, use tty from tty_port" switched the driver
to use tty_port helper for tty refcounting. But it omitted to remove
manual tty refcounting from open, close and hangup. So now we are
getting random crashes caused by use-after-free:
Unable to handle kernel paging request for data at address 0xc0000003f9d550
Faulting instruction address: 0xc0000000001b7f40
Oops: Kernel access of bad area, sig: 11 [#1]
...
NIP: c0000000001b7f40 LR: c0000000001b7f14 CTR: c0000000000e04f0
...
NIP [c0000000001b7f40] .__kmalloc+0x70/0x230
LR [c0000000001b7f14] .__kmalloc+0x44/0x230
Call Trace:
[c0000003f68bf930] [c0000003f68bf9b0] 0xc0000003f68bf9b0 (unreliable)
[c0000003f68bf9e0] [c0000000001e5424] .alloc_fdmem+0x24/0x70
[c0000003f68bfa60] [c0000000001e54f8] .alloc_fdtable+0x88/0x130
[c0000003f68bfaf0] [c0000000001e5924] .dup_fd+0x384/0x450
[c0000003f68bfbd0] [c00000000009a310] .copy_process+0x880/0x11d0
[c0000003f68bfcd0] [c00000000009aee0] .do_fork+0x70/0x400
[c0000003f68bfdc0] [c0000000000141c4] .sys_clone+0x54/0x70
[c0000003f68bfe30] [c000000000009aa0] .ppc_clone+0x8/0xc
Fix that by complete removal of tty_kref_get/put in open/close/hangup
paths.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-and-tested-by: Michael Neuling <mikey@neuling.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: ppc-dev <linuxppc-dev@lists.ozlabs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are some tty and serial fixes for 3.4-rc2.
Most important here is the pl011 fix, which has been reported by about
100 different people, which means more people use it than I expected :)
There are also some 8250 driver reverts due to some problems reported by
them. And other minor fixes as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty and serial fixes from Greg KH:
"Here are some tty and serial fixes for 3.4-rc2.
Most important here is the pl011 fix, which has been reported by about
100 different people, which means more people use it than I expected
:)
There are also some 8250 driver reverts due to some problems reported
by them. And other minor fixes as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'tty-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
pch_uart: Add Kontron COMe-mTT10 uart clock quirk
pch_uart: Fix MSI setting issue
serial/8250_pci: add a "force background timer" flag and use it for the "kt" serial port
Revert "serial/8250_pci: setup-quirk workaround for the kt serial controller"
Revert "serial/8250_pci: init-quirk msi support for kt serial controller"
tty/serial/omap: console can only be built-in
serial: samsung: fix omission initialize ulcon in reset port fn()
printk(): add KERN_CONT where needed in hpet and vt code
tty/serial: atmel_serial: fix RS485 half-duplex problem
tty: serial: altera_uart: Check for NULL platform_data in probe.
isdn/gigaset: use gig_dbg() for debugging output
omap-serial: Fix the error handling in the omap_serial probe
serial: PL011: move interrupt clearing
tty_buffer_request_room is well protected, but while after it returns,
it releases the port->lock. tty->buf.tail might be modified
by either irq handler or other threads. The patch adds more protection
by holding the lock across tty buffer finding and buffer filling.
Signed-off-by: Alek Du <alek.du@intel.com>
Signed-off-by: Xiaobing Tu <xiaobing.tu@intel.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
set_get_cmap() ignored the result of {get,put}_user(), causing ioctl(vt,
{G,P}IO_CMAP, 0xdeadbeef) to silently fail.
Another side effect of this: calling the PIO_CMAP ioctl with an invalid
buffer would zero the default colormap and the palette for all vts (all
colors set to black).
Leave the default colormap intact and return -EFAULT when
reading/writing to the userspace buffer fails.
Signed-off-by: Michael Gehring <mg@ebfe.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, occurring line status interrupt,
returned value is not set in interrupt handler function.
As a result, 0 can be returned.
This patch adds setting returned value.
Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
%02x format is easier to understand better than %d.
Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Target uart register access size is 8bit.
However, 32bit is used at 2 points.
This patch modifies type "unsigned int" to "unsigned char".
Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the code is identical, use the tty_port_block_til_ready helper
instead of re-implemented variant.
The code does not perform rtsdts handling, hence we do not need to
provide tty port hooks for them. The default ones will be used
instead. The only necessary thing is to provide tty_port_operations.
It is empty, but has to be there...
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need tty at some places, but info->tty might be NULL at those. Let
us propagate tty from callers where we know we have a valid tty. This
will make a switch to tty refcounting simpler.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
flags passed to local_irq_save/restore should be ulong. Switch tehem
to that. Otherwise we get compilation warnings:
.../68328serial.c:248:9: warning: comparison of distinct pointer types lacks a cast [enabled by default]
.../68328serial.c:257:9: warning: comparison of distinct pointer types lacks a cast [enabled by default]
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
