| 0772b6e5e9272ca233c5ed8715fe36b41a82eaff |
|
30-Jul-2009 |
San Mehat <san@google.com> |
serial_core: Add wake_peer uart operation
Add wake_peer which is called before starting UART TX. The idea here
is to provide a mechanism where we can wakeup our peer before sending
data.
Change-Id: I42e0779b635f64ca99184b45d5b028de80197491
Signed-off-by: San Mehat <san@google.com>
|
| 547039ec502076e60034eeb79611df3433a99b7d |
|
16-Oct-2014 |
Peter Hurley <peter@hurleysoftware.com> |
serial: Fix divide-by-zero fault in uart_get_divisor()
uart_get_baud_rate() will return baud == 0 if the max rate is set
to the "magic" 38400 rate and the SPD_* flags are also specified.
On the first iteration, if the current baud rate is higher than the
max, the baud rate is clamped at the max (which in the degenerate
case is 38400). On the second iteration, the now-"magic" 38400 baud
rate selects the possibly higher alternate baud rate indicated by
the SPD_* flag. Since only two loop iterations are performed, the
loop is exited, a kernel WARNING is generated and a baud rate of
0 is returned.
Reproducible with:
setserial /dev/ttyS0 spd_hi base_baud 38400
Only perform the "magic" 38400 -> SPD_* baud transform on the first
loop iteration, which prevents the degenerate case from recognizing
the clamped baud rate as the "magic" 38400 value.
Reported-by: Robert Święcki <robert@swiecki.net>
Cc: <stable@vger.kernel.org> # all
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 69784fa539efa477f39b5a849c27d5e630e0db27 |
|
03-Oct-2014 |
Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
Revert "serial/core: Initialize the console pm state"
This reverts commit a86713b1536c818972675e6dd8c6e738f0379f1d.
Kevin Hilman writes:
Multiple boot failures on ARM[1] were bisected down to this
patch.
How was this patch tested, and on which platforms?
Also, the changelog states that this should be done only for
UART_CAP_SLEEP, but the patch does it for every UART.
Greg, I suggest this patch be dropped from tty-next until it has
been better described and tested.
[1] http://lists.linaro.org/pipermail/kernel-build-reports/2014-October/005550.html
Reported-by: Kevin Hilman <khilman@kernel.org>
Cc: Sudhir Sreedharan <ssreedharan@mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| a86713b1536c818972675e6dd8c6e738f0379f1d |
|
21-Sep-2014 |
Sudhir Sreedharan <ssreedharan@mvista.com> |
serial/core: Initialize the console pm state
For console devices having UART_CAP_SLEEP capability, the uart_pm_state has
to be initialized to UART_PM_STATE_ON. Otherwise the LCR regiser values
are reinitialized when uart_change_pm is called from uart_configure_port.
Signed-off-by: Sudhir Sreedharan <ssreedharan@mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 938f7e13b55a76ad98964509f6d13bbcf852e617 |
|
10-Sep-2014 |
Peter Hurley <peter@hurleysoftware.com> |
serial: core: Use spin_lock_irq() in uart_set_termios()
uart_set_termios() is called with interrupts enabled; no need to
save and restore the interrupt state when taking the uart port lock.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| d01f4d181c92877ecc678adce248a30cb7077ff1 |
|
10-Sep-2014 |
Peter Hurley <peter@hurleysoftware.com> |
serial: core: Privatize tty->hw_stopped
tty->hw_stopped is not used by the tty core and is thread-unsafe;
hw_stopped is a member of a bitfield whose fields are updated
non-atomically and no lock is suitable for serializing updates.
Replace serial core usage of tty->hw_stopped with uport->hw_stopped.
Use int storage which works around Alpha EV4/5 non-atomic byte storage,
since uart_port uses different locks to protect certain fields within the
structure.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 299245a145b2ad4cfb4c5432eb1264299f55e7e0 |
|
10-Sep-2014 |
Peter Hurley <peter@hurleysoftware.com> |
serial: core: Privatize modem status enable flags
The serial core uses the tty port flags, ASYNC_CTS_FLOW and
ASYNC_CD_CHECK, to track whether CTS and DCD changes should be
ignored or handled. However, the tty port flags are not safe for
atomic bit operations and no lock provides serialized updates.
Introduce the struct uart_port status field to track CTS and DCD
enable states, and serialize access with uart port lock. Substitute
uart_cts_enabled() helper for tty_port_cts_enabled().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 4d90bb147ef6b91f529a21b498ff2b5fdc6785b4 |
|
10-Sep-2014 |
Peter Hurley <peter@hurleysoftware.com> |
serial: core: Document and assert lock requirements for irq helpers
The serial core provides two helper functions, uart_handle_dcd_change()
and uart_handle_cts_change(), for UART drivers to use at interrupt
time. The serial core expects the UART driver to hold the uart port lock
when calling these helpers to prevent state corruption.
If lockdep enabled, trigger a warning if the uart port lock is not held
when calling these helper functions.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| c993257bf7571945201205491de86268437ea174 |
|
02-Sep-2014 |
Peter Hurley <peter@hurleysoftware.com> |
serial: core: Unwrap tertiary assignment in uart_handle_dcd_change()
Prepare for spin lock assertion; move non-trivial assignment into
function body.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| fba594a848f6f35417a358565086d22c533c19c8 |
|
02-Sep-2014 |
Peter Hurley <peter@hurleysoftware.com> |
serial: core: Remove unsafe x_char optimization
uart_unthrottle() attempts to avoid sending START and the previous
x_char if the previous x_char has not yet been sent. However, this
optimization could leave the sender in a throttled state; for example,
if the sender is throttled and this unthrottle coincides with a manual
tcflow(TCION) from user-space, then neither START would be sent.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| c235ccc1c4d6fd8b7d48b976b87416230ffd5149 |
|
02-Sep-2014 |
Peter Hurley <peter@hurleysoftware.com> |
serial: core: Fix x_char race
The UART driver is expected to clear port->x_char after
transmission while holding the port->lock. However, the serial
core fails to take the port->lock before assigning port->xchar.
This allows for the following race
CPU 0 | CPU 1
|
| serial8250_handle_irq
| ...
| serial8250_tx_chars
| if (port->x_char)
| serial_out(up, UART_TX, port->x_char)
uart_send_xchar |
port->x_char = ch |
| port->x_char = 0
port->ops->start_tx() |
|
The x_char on CPU 0 will never be sent.
Take the port->lock in uart_send_xchar() before assigning port->x_char.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 99abf3b9242fbc5fec586223a5068544e0e9d90f |
|
02-Sep-2014 |
Peter Hurley <peter@hurleysoftware.com> |
serial: Style fix
Unwrap if() conditional; no functional change.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| a6eec92ec0815ce8ce57e4746e9f717d4146d869 |
|
02-Sep-2014 |
Peter Hurley <peter@hurleysoftware.com> |
Revert "serial: uart: add hw flow control support configuration"
This reverts commit 06aa82e498c144c7784a6f3d3b55458b272d6146.
This commit purports to enable auto CTS flow control for the 8250
UART driver. However, the 8250 UART driver already supports auto
CTS flow control via UART_CAP_AFE and UART_CAP_EFR. Indeed, this
patch introduces another DT attribute for which an existing firmware
flag already exists ("auto-flow-control"). Furthermore, the use of
UPF_HARD_FLOW requires the UART driver to define .throttle and
.unthrottle methods, neither of which are defined for the 8250 UART
driver (which will result in a NULL ptr dereference). Finally, this patch
supposes to fix existing bugs in the serial core for auto CTS-enabled
hardware, but does not include the class of hardware for which these
bugs exist.
CC: Murali Karicheri <m-karicheri2@ti.com>
CC: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 2f2dafe77df2c78e189a9fa6b1879dffd06ae5a1 |
|
01-Sep-2014 |
Sudip Mukherjee <sudipm.mukherjee@gmail.com> |
serial: serial_core.c: printk replacement
printk replaced with corresponding dev_* .
fixed two broken user-visible strings used by the corresponding printk.
the null check for uport->dev and port->dev is removed as dev_* will check for
null while printing.
printing of dev_name(uport->dev) and dev_name(port->dev) also removed as those
are being printed by dev_* .
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| c2b703b807e3aba4d2b542c9096c790186a6e71f |
|
23-Jul-2014 |
Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> |
serial/core: Fix too big allocation for attribute member
Current code allocates too much data for tty_groups member of uart_port struct,
so fix it.
Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 266dcff03eed0050b6af11aaf2a61ab837d7ba3f |
|
16-Jul-2014 |
Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
Serial: allow port drivers to have a default attribute group
Some serial drivers (like 8250), want to add sysfs files. We need to do
so in a race-free way, so allow any port to be able to specify an
attribute group that should be added at device creation time.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| c18b55fd1717a4c08c9f3555be63da142767e6b8 |
|
16-Jun-2014 |
Peter Hurley <peter@hurleysoftware.com> |
tty: serial: Fix termios/port flags mismatch
Uart port drivers may reconfigure termios settings based on available
hardware support; set/clear ASYNC_CTS_FLOW and ASYNC_CHECK_CD _after_
calling the port driver's .set_termios method.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| e359a4e38d229d53e28905863a1fabf41debd591 |
|
16-Jun-2014 |
Peter Hurley <peter@hurleysoftware.com> |
tty: Remove tty_hung_up_p() tests from tty drivers' open()
Since at least before 2.6.30, it has not been possible to observe
a hung up file pointer in a tty driver's open() method unless/until
the driver open() releases the tty_lock() (eg., before blocking).
This is because tty_open() adds the file pointer while holding
the tty_lock() _and_ doesn't release the lock until after calling
the tty driver's open() method. [ Before tty_lock(), this was
lock_kernel(). ]
Since __tty_hangup() first waits on the tty_lock() before
enumerating and hanging up the open file pointers, either
__tty_hangup() will wait for the tty_lock() or tty_open() will
not yet have added the file pointer. For example,
CPU 0 | CPU 1
|
tty_open | __tty_hangup
.. | ..
tty_lock | ..
tty_reopen | tty_lock / blocks
.. |
tty_add_file(tty, filp) |
.. |
tty->ops->open(tty, filp) |
tty_port_open |
tty_port_block_til_ready |
.. |
while (1) |
.. |
tty_unlock | / unblocks
schedule | for each filp on tty->tty_files
| f_ops = tty_hung_up_fops;
| ..
| tty_unlock
tty_lock |
.. |
tty_unlock |
Note that since tty_port_block_til_ready() and similar drop
the tty_lock while blocking, when woken, the file pointer
must then be tested for having been hung up.
Also, fix bit-rotted drivers that used extra_count to track the
port->count bump.
CC: Mikael Starvik <starvik@axis.com>
CC: Samuel Ortiz <samuel@sortiz.org>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| ddc7b758a6765bd7f853b829104bb7a486a304ad |
|
16-Jun-2014 |
Peter Hurley <peter@hurleysoftware.com> |
tty: Move tty->closing from port lock critical section
tty->closing informs the line discipline that the hardware will
be shutting down imminently, and to disable further input other
than soft flow control (but to still allow additional output).
However, the tty lock is the necessary lock for preventing
concurrent changes to tty->closing. As shown by the call-tree
audit [1] of functions that modify tty->closing, the tty lock
is already held for those functions.
[1]
Call-tree audit of functions that modify tty->closing
* does not include call tree to tty_port_close(), tty_port_close_start(),
or tty_port_close_end() which is already documented in
'tty: Document locking for tty_port_close{,start,end}' that shows
callers to those 3 functions hold the tty lock
tty_release()
tty->ops->close() --+
|
__tty_hangup() |
tty->ops->close() --+
|
mp_close():drivers/staging/sb105x/sb_pci_mp.c
dngc_tty_close():drivers/staging/dgnc/dgnc_tty.c
dgap_tty_close():drivers/staging/dgap/dgap_tty.c
dgrp_tty_close():drivers/staging/dgrp/dgrp_tty.c
rp_close():drivers/tty/rocket.c
hvsi_close():drivers/tty/hvc/hvsi.c
rs_close():drivers/tty/serial/68328serial.c
rs_close():drivers/tty/serial/crisv10.c
uart_close():drivers/tty/serial/serial_core.c
isdn_tty_close():drivers/isdn/i4l/isdn_tty.c
tty3215_close():drivers/s390/char/con3215.c
tty_open()
tty_ldisc_setup() ----+
|
__tty_hangup() |
tty_ldisc_hangup() ---+
|
tty_set_ldisc() --------+
tty_ldisc_restore() --+
|
+- tty_ldisc_open()
ld->ops->open() --+
|
+- n_tty_open()
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| ae84db9661cafc63d179e1d985a2c5b841ff0ac4 |
|
09-Jul-2014 |
Peter Hurley <peter@hurleysoftware.com> |
serial: core: Preserve termios c_cflag for console resume
When a tty is opened for the serial console, the termios c_cflag
settings are inherited from the console line settings.
However, if the tty is subsequently closed, the termios settings
are lost. This results in a garbled console if the console is later
suspended and resumed.
Preserve the termios c_cflag for the serial console when the tty
is shutdown; this reflects the most recent line settings.
Fixes: Bugzilla #69751, 'serial console does not wake from S3'
Reported-by: Valerio Vanni <valerio.vanni@inwind.it>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 1fdc31065fdf95ded3b1960d1426e1da43b297ef |
|
03-Jun-2014 |
Alexander Shiyan <shc_work@mail.ru> |
serial: core: Make enable_ms() optional
This patch makes enable_ms() optional, so we can eliminate a lot of
empty enable_ms() implementations from driver code.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| a208ffd251d08ed7ba6bdf3ae1e423373fb12d3d |
|
28-Mar-2014 |
Grant Likely <grant.likely@linaro.org> |
of: Enable console on serial ports specified by /chosen/stdout-path
If the devicetree specifies a serial port as a stdout device, then the
kernel can use it as the default console if nothing else was selected on
the command line. For any serial port that uses the uart_add_one_port()
feature, the uart_add_one_port() has all the information needed to
automatically enable the console device, which is what this patch does.
With this change applied, a device tree platform can be booted without
any console= parameters on the command line and the kernel will still be
able to determine its console.
Tested on QEMU Versatile model and i.MX
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
|
| 06aa82e498c144c7784a6f3d3b55458b272d6146 |
|
01-May-2014 |
Murali Karicheri <m-karicheri2@ti.com> |
serial: uart: add hw flow control support configuration
8250 uart driver currently supports only software assisted hw flow
control. The software assisted hw flow control maintains a hw_stopped
flag in the tty structure to stop and start transmission and use modem
status interrupt for the event to drive the handshake signals. This is
not needed if hw has flow control capabilities. This patch adds a
DT attribute for enabling hw flow control for a uart port. Also skip
stop and start if this flag is present in flag field of the port
structure.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
CC: Rob Herring <robh+dt@kernel.org>
CC: Pawel Moll <pawel.moll@arm.com>
CC: Mark Rutland <mark.rutland@arm.com>
CC: Ian Campbell <ijc+devicetree@hellion.org.uk>
CC: Kumar Gala <galak@codeaurora.org>
CC: Randy Dunlap <rdunlap@infradead.org>
CC: Jiri Slaby <jslaby@suse.cz>
CC: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| c7d44a02ac606c2bebf90751deebec2321379d6d |
|
21-Apr-2014 |
Doug Anderson <dianders@chromium.org> |
serial_core: Commonalize crlf when working w/ a non open console port
In (efe2f29 kgdboc,kdb: Allow kdb to work on a non open console port)
support was added to directly use the "write_char" functions when
doing kdb over a non-open console port. This is great, but it ends up
bypassing the normal code in uart_console_write() that adds a carriage
return before any newlines.
There appears to have been a trend to add this support directly in
some console driver's poll_put_char() functions. This had a few side
effects, including:
- In this case we were doing LFCR, not CRLF. This was fixed in
uart_console_write() back in (d358788 [SERIAL] kernel console should
send CRLF not LFCR)
- Not all serial drivers had the LFCR code in their poll_put_char()
functions. In my case I was running serial/samsung.c which lacked
it.
I've moved the handling to uart_poll_put_char() to fix the above
problems. Now when I use kdb (and don't point console= to the same
UART) I no longer get:
[0]kdb>
[0]kdb>
[0]kdb>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 7deb39ed8d9494ea541bcaa69b56036a94f79dc2 |
|
23-Apr-2014 |
Thomas Pfaff <tpfaff@pcs.com> |
serial_core: fix uart PORT_UNKNOWN handling
While porting a RS485 driver from 2.6.29 to 3.14, i noticed that the serial tty
driver could break it by using uart ports that it does not own :
1. uart_change_pm ist called during uart_open and calls the uart pm function
without checking for PORT_UNKNOWN.
The fix is to move uart_change_pm from uart_open to uart_port_startup.
2. The return code from the uart request_port call in uart_set_info is not
handled properly, leading to the situation that the serial driver also
thinks it owns the uart ports.
This can triggered by doing following actions :
setserial /dev/ttyS0 uart none # release the uart ports
modprobe lirc-serial # or any other device that uses the uart
setserial /dev/ttyS0 uart 16550 # gives no error and the uart tty driver
# can use the ports as well
Signed-off-by: Thomas Pfaff <tpfaff@pcs.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| bf903c0c6ddfedec19ba92626ca30e98bfafbe08 |
|
27-Mar-2014 |
Geert Uytterhoeven <geert+renesas@glider.be> |
serial_core: Fix pm imbalance on unbind
When a serial port is closed, uart_close() takes care of shutting down the
hardware, and powering it down.
When a serial port is unbound while in use, uart_close() bypasses all of
this, as this is supposed to be done through uart_hangup() (invoked via
tty_vhangup() in uart_remove_one_port()).
However, uart_hangup() does not set the hardware's power state, leaving it
powered up. This may also lead to unbounded nesting counts in clock and
power management, depending on their internal implementation.
Make sure to power down the port in uart_hangup(), except when the port is
used as a serial console.
For serial consoles, this operation must be postponed until after the port
becomes completely unused. This case is not fixed yet, as it depends on a
(future) fix for the tty->count vs. port->count imbalance on failed
uart_open().
After this, the module clock used by the sh-sci driver is disabled on
unbind while the serial port is in use.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 717f3bbab3c7628736ef738fdbf3d9a28578c26c |
|
25-Mar-2014 |
Seth Bollinger <sethb@digi.com> |
serial_core: Fix conditional start_tx on ring buffer not empty
If the serial_core ring buffer empties just as the tty layer receives
an XOFF, then start_tx will never be called when the tty layer
receives an XON as the serial_core ring buffer is empty. This will
possibly leave a few bytes trapped in the fifo for drivers that
disable the transmitter when flow controlled.
Signed-off-by: Seth Bollinger <sethb@digi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 4ed94cd44039037980ce66c652b194ec21356268 |
|
17-Mar-2014 |
Geert Uytterhoeven <geert+renesas@linux-m68k.org> |
serial_core: Avoid NULL pointer dereference in uart_close()
When unbinding a serial driver that's being used as a serial console,
the kernel may crash with a NULL pointer dereference in a uart_*() function
called from uart_close () (e.g. uart_flush_buffer() or
uart_chars_in_buffer()).
To fix this, let uart_close() check for port->count == 0. If this is the
case, bail out early. Else tty_port_close_start() will make the port
counts inconsistent, printing out warnings like
tty_port_close_start: tty->count = 1 port count = 0.
and
tty_port_close_start: count = -1
and once uport == NULL, it will also crash.
Also fix the related crash in pr_debug() by checking for a non-NULL uport
first.
Detailed description:
On driver unbind, uart_remove_one_port() is called. Basically it;
- marks the port dead,
- calls tty_vhangup(),
- sets state->uart_port = NULL.
What will happen depends on whether the port is just in use by e.g. getty,
or was also opened as a console.
A. If the tty was not opened as a console:
- tty_vhangup() will (in __tty_hangup()):
- mark all file descriptors for this tty hung up by pointing them to
hung_up_tty_fops,
- call uart_hangup(), which sets port->count to 0.
- A subsequent uart_open() (this may be through /dev/ttyS*, or through
/dev/console if this is a serial console) will fail with -ENXIO as the
port was marked dead,
- uart_close() after the failed uart_open() will return early, as
tty_hung_up_p() (called from tty_port_close_start()) will notice it was
hung up.
B. If the tty was also opened as a console:
- tty_vhangup() will (in __tty_hangup()):
- mark non-console file descriptors for this tty hung up by pointing
them to hung_up_tty_fops,
- NOT call uart_hangup(), but instead call uart_close() for every
non-console file descriptor, so port->count will still have a
non-zero value afterwards.
- A subsequent uart_open() will fail with -ENXIO as the port was
marked dead,
- uart_close() after the failed uart_open() starts to misbehave:
- tty_hung_up_p() will not notice it was hung up,
- As port->count is non-zero, tty_port_close_start() will decrease
port->count, making the tty and port counts inconsistent. Later,
warnings like these will be printed:
tty_port_close_start: tty->count = 1 port count = 0.
and
tty_port_close_start: count = -1
- If all of this happens after state->uart_port was set to zero, a
NULL pointer dereference will happen.
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 4c6d5b4d537fbdfa310295e7071c85b07783d245 |
|
17-Mar-2014 |
Geert Uytterhoeven <geert+renesas@linux-m68k.org> |
serial_core: Get a reference for port->tty in uart_remove_one_port()
Suggested-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 015355b70e074a8cc11da6ae4f82d45c5160358a |
|
11-Mar-2014 |
Geert Uytterhoeven <geert+renesas@linux-m68k.org> |
serial_core: Grammar s/ports/port's/
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 02088ca63b2de4f7eb575c46fc9ff3d60775b07f |
|
11-Mar-2014 |
Geert Uytterhoeven <geert+renesas@linux-m68k.org> |
serial_core: Spelling s/contro/control/
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 5f5c9ae56c38942623f69c3e6dc6ec78e4da2076 |
|
28-Feb-2014 |
Geert Uytterhoeven <geert+renesas@linux-m68k.org> |
serial_core: Unregister console in uart_remove_one_port()
If the serial port being removed is used as a console, it must also be
unregistered from the console subsystem using unregister_console().
uart_ops.release_port() will release resources (e.g. iounmap() the serial
port registers), causing a crash on subsequent kernel output if the console
is still registered.
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 42b6a1baa3ec18de2eb15baa250da6203eeb2d39 |
|
17-Oct-2013 |
Randy Witt <rewitt@declaratino.com> |
serial_core: Don't re-initialize a previously initialized spinlock.
The uart_set_options() code unconditionally initalizes the spinlock
on the port. This can cause a deadlock in some situations.
One instance that exposed the problem, was when writing to
/sys/module/kgdboc/parameters/kgdboc to use ttyS0 when the console
is already running on ttyS0. If the spinlock is re-initialized
while the lock is held due to output to the console, there
is a deadlock.
Assume the spinlock is initialized if the port is a console.
Signed-off-by: Randy Witt <rewitt@declaratino.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 7d12b9769f39bec1630c6a1947e8615ce26c9a52 |
|
12-Jul-2013 |
Kees Cook <keescook@chromium.org> |
serial: report base_baud after initialization
Some serial ports will not use the standard base baud rate. Report
this after initialization so it might be discovered and used for early
console configuration.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| cf0ebee0d0374c6d75494ac96f86b4aea482dd09 |
|
15-May-2013 |
Sourav Poddar <sourav.poddar@ti.com> |
serial: Move "uart_console" def to core header file.
Move "uart_console" definition to serial core header file, so that it can be
used by serial drivers.
Get rid of the uart_console defintion from mpc52xx_uart driver.
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Rajendra nayak <rnayak@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 5a65dcc04cda41f4122aacc37a5a348454645399 |
|
15-Apr-2013 |
Federico Vaga <federico.vaga@gmail.com> |
serial_core.c: add put_device() after device_find_child()
The serial core uses device_find_child() but does not drop the reference to
the retrieved child after using it. This patch add the missing put_device().
What I have done to test this issue.
I used a machine with an AMBA PL011 serial driver. I tested the patch on
next-20120408 because the last branch [next-20120415] does not boot on this
board.
For test purpose, I added some pr_info() messages to print the refcount
after device_find_child() (lines: 1937,2009), and after put_device()
(lines: 1947, 2021).
Boot the machine *without* put_device(). Then:
echo reboot > /sys/power/disk
echo disk > /sys/power/state
[ 87.058575] uart_suspend_port:1937 refcount 4
[ 87.058582] uart_suspend_port:1947 refcount 4
[ 87.098083] uart_resume_port:2009refcount 5
[ 87.098088] uart_resume_port:2021 refcount 5
echo disk > /sys/power/state
[ 103.055574] uart_suspend_port:1937 refcount 6
[ 103.055580] uart_suspend_port:1947 refcount 6
[ 103.095322] uart_resume_port:2009 refcount 7
[ 103.095327] uart_resume_port:2021 refcount 7
echo disk > /sys/power/state
[ 252.459580] uart_suspend_port:1937 refcount 8
[ 252.459586] uart_suspend_port:1947 refcount 8
[ 252.499611] uart_resume_port:2009 refcount 9
[ 252.499616] uart_resume_port:2021 refcount 9
The refcount continuously increased.
Boot the machine *with* this patch. Then:
echo reboot > /sys/power/disk
echo disk > /sys/power/state
[ 159.333559] uart_suspend_port:1937 refcount 4
[ 159.333566] uart_suspend_port:1947 refcount 3
[ 159.372751] uart_resume_port:2009 refcount 4
[ 159.372755] uart_resume_port:2021 refcount 3
echo disk > /sys/power/state
[ 185.713614] uart_suspend_port:1937 refcount 4
[ 185.713621] uart_suspend_port:1947 refcount 3
[ 185.752935] uart_resume_port:2009 refcount 4
[ 185.752940] uart_resume_port:2021 refcount 3
echo disk > /sys/power/state
[ 207.458584] uart_suspend_port:1937 refcount 4
[ 207.458591] uart_suspend_port:1947 refcount 3
[ 207.498598] uart_resume_port:2009 refcount 4
[ 207.498605] uart_resume_port:2021 refcount 3
The refcount correctly handled.
Signed-off-by: Federico Vaga <federico.vaga@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| d9dda78bad879595d8c4220a067fc029d6484a16 |
|
01-Apr-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
procfs: new helper - PDE_DATA(inode)
The only part of proc_dir_entry the code outside of fs/proc
really cares about is PDE(inode)->data. Provide a helper
for that; static inline for now, eventually will be moved
to fs/proc, along with the knowledge of struct proc_dir_entry
layout.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
| bc80fbe46be7430487a45ad92841932bb2eaa3e6 |
|
06-Feb-2013 |
Peter Hurley <peter@hurleysoftware.com> |
tty: Remove ancient hardpps()
hardpps() functionality is provided through the N_PPS line
discipline now. The new function signature was added in commit
025b40ab (2011-01-12). There was no previous macro or
function hardpps(), at least since before the initial commit of
v2.6.12 in 2005. It's unlikely this code has been compiled since.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: George Spelvin <linux@horizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 42381572f586d4da57e7d65e0fcb45422be3ba7b |
|
10-Feb-2013 |
George Spelvin <linux@horizon.com> |
pps: Additional cleanups in uart_handle_dcd_change
An extension of the previous commit, there is no semantic change
here, just fewer lines of source code.
Signed-off-by: George Spelvin <linux@horizon.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 593fb1ae457aab28b392ac114f6e3358788da985 |
|
12-Feb-2013 |
George Spelvin <linux@horizon.com> |
pps: Move timestamp read into PPS code proper
The PPS (Pulse-Per-Second) line discipline has developed a number of
unhealthy attachments to core tty data and functions, ultimately leading
to its breakage.
The previous patches fixed the crashing. This one reduces coupling further
by eliminating the timestamp parameter from the dcd_change ldisc method.
This reduces header file linkage and makes the extension more generic,
and the timestamp read is delayed only slightly, from just before the
ldisc->ops->dcd_change method call to just after.
Fix attendant build breakage in
drivers/tty/n_tty.c
drivers/tty/tty_buffer.c
drivers/staging/speakup/selection.c
drivers/staging/dgrp/dgrp_*.c
Cc: William Hubbs <w.d.hubbs@gmail.com>
Cc: Chris Brannon <chris@the-brannons.com>
Cc: Kirk Reiser <kirk@braille.uwo.ca>
Cc: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: George Spelvin <linux@horizon.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| b342dd512f7af0e0e14e29c3e1f863150cfc46ff |
|
27-Dec-2012 |
Chen Gang <gang.chen@asianux.com> |
drivers/tty/serial: extern function which for release resource, need check pointer, before free it
for extern function uart_remove_one_port:
need check pointer whether be NULL, before the main work.
just like what the other extern function uart_add_one_port has done.
uart_add_one_port and uart_remove_one_port are pair
information:
for the callers (such as drivers/tty/serial/jsm: jsm_tty.c, jsm_driver.c)
they realy assume that:
they still can call uart_remove_one_port, after uart_add_one_port failed
we (as an extern function), have to understand it (just like kfree).
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| d6c53c0e9bd0a83f9f9ddbc9fd80141a54d83896 |
|
03-Jan-2013 |
Jiri Slaby <jslaby@suse.cz> |
TTY: move low_latency to tty_port
One point is to have less places where we actually need tty pointer.
The other is that low_latency is bound to buffer processing and
buffers are now in tty_port. So it makes sense to move low_latency to
tty_port too.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 92a19f9cec9a80ad93c06e115822deb729e2c6ad |
|
03-Jan-2013 |
Jiri Slaby <jslaby@suse.cz> |
TTY: switch tty_insert_flip_char
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.
tty_insert_flip_char is the next one to proceed. This one is used all
over the code, so the patch is huge.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| ef4f527c48c8fcbb5e35dafaef4f9097f5e9d901 |
|
27-Dec-2012 |
Kevin Cernekee <cernekee@gmail.com> |
tty: Fix comments that reference BKL, eventd, old paths
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 6f538fe31c1d453b7e7fc4f6e7c6a9bdead4a6f2 |
|
07-Dec-2012 |
Linus Walleij <linus.walleij@linaro.org> |
tty: serial core: decouple pm states from ACPI
The serial core is using power states lifted from ACPI for no
good reason. Remove this reference from the documentation and
alter all users to use an enum specific to the serial core
instead, and define it in <linux/serial_core.h>.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| fd985e1def964bb3a3adf5e2760af10510fd3f58 |
|
27-Nov-2012 |
Andrew Morton <akpm@linux-foundation.org> |
drivers/tty/serial/serial_core.c: clean up HIGH_BITS_OFFSET usage
serial_core.c usually does
if (HIGH_BITS_OFFSET)
expr-involving-HIGH_BITS_OFFSET()
at least to avoid generating useless code on 32-bit machines, where
HIGH_BITS_OFFSET is zero. Do that in uart_get_attr_port().
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 191c5f10275cfbb36802edadbdb10c73537327b4 |
|
15-Nov-2012 |
Jiri Slaby <jslaby@suse.cz> |
TTY: call tty_port_destroy in the rest of drivers
After commit "TTY: move tty buffers to tty_port", the tty buffers are
not freed in some drivers. This is because tty_port_destructor is not
called whenever a tty_port is freed. This was an assumption I counted
with but was unfortunately untrue. So fix the drivers to fulfil this
assumption.
To be sure, the TTY buffers (and later some stuff) are gone along with
the tty_port, we have to call tty_port_destroy at tear-down places.
This is mostly where the structure containing a tty_port is freed.
This patch does exactly that -- put tty_port_destroy at those places.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 7a876b39b5bc94f67e8a3a7adfd270b8c21fc762 |
|
06-Nov-2012 |
Alan Cox <alan@linux.intel.com> |
serial: cast before shifting on port io
Without this we will shift data into oblivion and give wrong results on
some configurations
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 9aba8d5b011193c8e01d565c5b585df5b94f1db2 |
|
17-Apr-2012 |
Russell King <rmk+kernel@arm.linux.org.uk> |
SERIAL: core: add throttle/unthrottle callbacks for hardware assisted flow control
Add two callbacks for hardware assisted flow control; we need to know
when the tty layers want us to stop and restart due to their buffer
levels.
Call a driver specific throttle/unthrottle function if and only if the
driver indicates that it is using an enabled hardware assisted flow
control method, otherwise fall back to the non-hardware assisted
methods.
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
|
| dba05832cbe4f305dfd998fb26d7c685d91fbbd8 |
|
17-Apr-2012 |
Russell King <rmk+kernel@arm.linux.org.uk> |
SERIAL: core: add hardware assisted h/w flow control support
Ports which are handling h/w flow control in hardware must not have
their RTS state altered depending on the tty's hardware-stopped state.
Avoid this additional logic when setting the termios state.
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
|
| 2cbacafd7af0f1cc7a433668c662a91ba6aabc1b |
|
17-Apr-2012 |
Russell King <rmk+kernel@arm.linux.org.uk> |
SERIAL: core: add hardware assisted s/w flow control support
Ports which are capable of handling s/w flow control in hardware to
know when the s/w flow control termios settings are changed. Add a
flag to allow the low level serial drivers to indicate that they
support this, and these changes should be propagated to them.
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
|
| dec94e70e12c39440e63159e0050d46795dfcf09 |
|
24-Sep-2012 |
Russell King <rmk+kernel@arm.linux.org.uk> |
SERIAL: core: use local variable uport in uart_set_termios()
This is to make the following change more clear.
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
|
| 373bac4cf4c3198cc6d6b9aec7c5d576a06f1f1c |
|
29-Oct-2012 |
Alan Cox <alan@linux.intel.com> |
uart: add other serial core layer get attributes
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 9f1096943a56c35cc85a0729ec759fd8a25e552f |
|
29-Oct-2012 |
Alan Cox <alan@linux.intel.com> |
uart: tidy the uart_get_info API
We pass both port and state because the original caller had both to hand.
With all the attribute callers this won't be true so do the conversion in
the function itself.
The current callers all do lock/query/unlock. This won't be true for future
set based cases but there are plenty of get ones that will exist so split
the code with a helper for the future cases.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| bebe73e31d98845c8b63e624c25a5da2d819345a |
|
29-Oct-2012 |
Alan Cox <alan@linux.intel.com> |
uart: update the sysfs handler to use uart_get_info
The two patches needed are now in the tree. The first added the sysfs
interface and directly accesses the uartclk. The second provides a
proper interface for getting the values.
Wire them together.
This formes a basis for both get and set methods for any of the other uart
properties and we can now fill them out further.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| c7f3e7087ab0abb52bb1286010f2c104fd38ca5c |
|
24-Sep-2012 |
Anton Vorontsov <anton.vorontsov@linaro.org> |
tty/serial/core: Introduce poll_init callback
It was noticed that polling drivers (like KGDB) are not able to use
serial ports if the ports were not previously initialized via console.
I.e. when booting with console=ttyAMA0 kgdboc=ttyAMA0, everything works
fine, but with console=ttyFOO kgdboc=ttyAMA0, the kgdboc doesn't work.
This is because we don't initialize the hardware. Calling ->startup() is
not an option, because drivers request interrupts there, and drivers
fail to handle situations when tty isn't opened with interrupts enabled.
So, we have to implement a new callback (actually, tty_ops already have
a similar callback), which does everything needed to initialize just the
hardware.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 43eca0aef73cc6f0d37ad139f1cbb810e62e409d |
|
19-Sep-2012 |
Alan Cox <alan@linux.intel.com> |
serial_core: Fix race in uart_handle_dcd_change
If a serial driver is called post hangup with a second DCD event then we
will attempt to get the ldisc of NULL. Check we have a tty before trying to
do anything with it.
This is still only safe within the uart layer if the caller holds the
relevant uart locks. We could do with a version where the tty is passed for
more general use.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| b1b799164afb22711e6bee718f2a5ee669bb9517 |
|
06-Sep-2012 |
Tomas Hlavacek <tmshlvck@gmail.com> |
tty_register_device_attr updated for tty-next
Added tty_device_create_release() and bound to dev->release in
tty_register_device_attr().
Added tty_port_register_device_attr() and used in uart_add_one_port()
instead of tty_register_device_attr().
Signed-off-by: Tomas Hlavacek <tmshlvck@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 6915c0e487c822e2436683e14302c0b8a6155cc7 |
|
06-Sep-2012 |
Tomas Hlavacek <tmshlvck@gmail.com> |
tty: uartclk value from serial_core exposed to sysfs
Added file /sys/devices/.../tty/ttySX/uartclk to allow reading
uartclk value in struct uart_port in serial_core via sysfs.
tty_register_device() has been generalized and refactored in order
to add support for setting drvdata and attribute_group to the device.
Signed-off-by: Tomas Hlavacek <tmshlvck@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 37cd0c994fc8ecbfb258c4be2442d9d6f31447ea |
|
06-Sep-2012 |
Fengguang Wu <fengguang.wu@intel.com> |
serial_core: fix sizeof(pointer)
sizeof when applied to a pointer typed expression gives the
size of the pointer.
Generated by: scripts/coccinelle/misc/noderef.cocci
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| f21ec3d2d46e5f2ffc06f31fe2704fdcea7a58f3 |
|
23-Aug-2012 |
Huang Shijie <shijie8@gmail.com> |
serial: add a new helper function
In most of the time, the driver needs to check if the cts flow control
is enabled. But now, the driver checks the ASYNC_CTS_FLOW flag manually,
which is not a grace way. So add a new wraper function to make the code
tidy and clean.
Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 7ba2e769825fef035a943ed74d90379245508764 |
|
04-Sep-2012 |
Alan Cox <alan@linux.intel.com> |
tty: Split the serial_core helpers for setserial into two
We want them split so that we can call them from setserial functionality
where we copy to/from user space and do the locking, but also from sysfs
where in future we'll want to came them within a sysfs context.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 734cc1783816ae358cef45673a29bf7af974e147 |
|
07-Aug-2012 |
Jiri Slaby <jslaby@suse.cz> |
TTY: use tty_port_register_device
Currently we have no way to assign tty->port while performing tty
installation. There are two ways to provide the link tty_struct =>
tty_port. Either by calling tty_port_install from tty->ops->install or
tty_port_register_device called instead of tty_register_device when
the device is being set up after connected.
In this patch we modify most of the drivers to do the latter. When the
drivers use tty_register_device and we have tty_port already, we
switch to tty_port_register_device. So we have the tty_struct =>
tty_port link for free for those.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 24a7d449b066bdba8b8b2486dc481f02043e0656 |
|
23-May-2012 |
Corbin <corbinat@gmail.com> |
serial_core: Update buffer overrun statistics.
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@xxxxxx>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| adc8d746caa67fff4b53ba3e5163a6cbacc3b523 |
|
14-Jul-2012 |
Alan Cox <alan@linux.intel.com> |
tty: move the termios object into the tty
This will let us sort out a whole pile of tty related races. The
alternative would be to keep points and refcount the termios objects.
However
1. They are tiny anyway
2. Many devices don't use the stored copies
3. We can remove a pty special case
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| dabfb351db690964f6c5f5729d4f407586f69a4f |
|
23-May-2012 |
Corbin <corbinat@gmail.com> |
serial_core: Update buffer overrun statistics.
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@xxxxxx>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 55e4b8b416849753bd7eacd1f2ac3947fcf1c78e |
|
15-May-2012 |
Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
Revert "serial_core: Update buffer overrun statistics."
This reverts commit 642180871bc91afebb6ccf40d1615a7dd33699a3.
Buffer overruns are for hardware reported overruns, not software ones,
which will only happen if we run out of memory and you will get lots of
-ENOMEM errors at the same time.
Thanks to Alan Cox for catching this.
Reported-by: Alan Cox <alan@linux.intel.com>
Cc: Corbin Atkinson <corbinat@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 1e66cded334e6cea596c72f6f650eec351b1e959 |
|
14-May-2012 |
Alan Cox <alan@linux.intel.com> |
tty: Allow uart_register/unregister/register
This is legitimate but because we don't clear the drv->state pointer in the
unregister code causes a bogus BUG().
Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=42880
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 642180871bc91afebb6ccf40d1615a7dd33699a3 |
|
04-May-2012 |
Corbin Atkinson <corbinat@gmail.com> |
serial_core: Update buffer overrun statistics.
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>
|
| 2f16669d322e05171c9e1cfd94f402f7399bd2a3 |
|
05-Mar-2012 |
Jiri Slaby <jslaby@suse.cz> |
TTY: remove re-assignments to tty_driver members
All num, magic and owner are set by alloc_tty_driver. No need to
re-set them on each allocation site.
pti driver sets something different to what it passes to
alloc_tty_driver. It is not a bug, since we don't use the lines
parameter in any way. Anyway this is fixed, and now we do the right
thing.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
| 773598357c0baf03081cf87f2b444f97744faf1e |
|
19-Jan-2012 |
Simon Glass <sjg@chromium.org> |
serial: Fix wakeup init logic to speed up startup
The synchronize_rcu() call resulting from making every serial driver
wake-up capable (commit b3b708fa) slows boot down on my Tegra2x system
(with CONFIG_PREEMPT disabled).
But this is avoidable since it is the device_set_wakeup_enable() and then
subsequence disable which causes the delay. We might as well just make
the device wakeup capable but not actually enable it for wakeup until
needed.
Effectively the current code does this:
device_set_wakeup_capable(dev, 1);
device_set_wakeup_enable(dev, 1);
device_set_wakeup_enable(dev, 0);
We can just drop the last two lines.
Before this change my boot log says:
[ 0.227062] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
[ 0.702928] serial8250.0: ttyS0 at MMIO 0x70006040 (irq = 69) is a Tegra
after:
[ 0.227264] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
[ 0.227983] serial8250.0: ttyS0 at MMIO 0x70006040 (irq = 69) is a Tegra
for saving of 450ms.
Suggested-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 97d24634daff8b83dae21cfde68553ff4997e558 |
|
20-Dec-2011 |
Uwe Kleine-König <u.kleine-koenig@pengutronix.de> |
serial: use DIV_ROUND_CLOSEST instead of open coding it
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| c0d92be6bc4fbbf6402fde2c0bc08fc4d2b58430 |
|
09-Nov-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, extract uart_port_startup
Extract ASYNC_INITIALIZED/TTY_IO_ERROR handling from uart_startup.
This will be useful for tty port helpers. These flags are handled
by the helpers instead.
So we create a new function uart_port_startup without touching these
flags there. And we keep uart_startup with the exact behavior as
before. We need that one because we start/stop the device from other
paths than open/close/hangup.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| b922e19d03a680d732b61dc8e82d9948f6f8b6c7 |
|
09-Nov-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, fill uart_port_shutdown
Let's fill the port_ops->shutdown. We will need this for hangup and
close port helpers.
We don't need to touch DTR/RTS registers in uart_port_shutdown. They
are set to off from port_close_start properly already.
Also we don't need to pin the TTY_IO_ERROR bit. This will be done in
close/hangup paths.
We leave uart_shutdown as is, because it is used (and will be) from
several paths now. Like from suspend.
The point is to not touch ASYNC_INITIALIZED bit. It will be set (and
checked) properly by the tty port helpers.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 0b1db83081599615cf7b254aebc14a2d8f6ca056 |
|
09-Nov-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, define uart_port_activate/shutdown
This is a preparation for the next patches which will move the stuff
from uart_open and uart_close/hangup here. Then we will use
tty_port_* helpers.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 1c7b13c4886f5cfaf02fb1052f65ef1a2fe88b9a |
|
09-Nov-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, inline uart_get
We need to expand uart_get into uart_open. We need it to move on with
conversion to use tty_port_open helper. After we do this, the code
will be much more similar to what tty_port_open does.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| b39c49a05ec7322c96ec917922eae8b908d2c76f |
|
09-Nov-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, do not touch tty->alt_speed
It is not used at all, so no need to play any games with that.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| cf75525f374dd5c49d705d9c8c3757f9aa3e9fd2 |
|
09-Nov-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, document few functions
Just put a kernel-doc comment to uart_change_pm and uart_insert_char.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| d30ccf08e8e01060288587f52a78c3ca0fcfc1fc |
|
09-Nov-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, use tty_port_close_start helper
After the previous patches, the code is almost identical. There are
few differences in the helper code:
1) flush_buffer when flow_stopped
* when a user doesn't care about the data, delete it anyways
2) ASYNCB_INITIALIZED test before wait_until_sent_from
* obviously, there is nothing to wait for if the port is dead
3) drain_delay wait
* we don't set drain_delay
So we can use the helper now. It indeed removes a bunch of duplicated
code.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 4cb0fbfdc81f29a414583bd05a9e324f8f19984d |
|
09-Nov-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, switch closing_wait and close_delay to jiffies
As the tty_port helpers think closing_wait and close_delay are in
jiffies and we want to use the helpers (next patches), we have to
switch the closing_wait and close_delay from ms to jiffies now.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 027d7dacf73273dbe07a75b2ef5579616f17272c |
|
09-Nov-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, cleanup include file
There are some functions (uart_handle_dcd_change, _handle_cts_change,
_insert_char) which are big enough to not be inlined. So move them
from .h to .c. We need to export them so that modules can actually use
them.
They will be even bigger when we introduce tty refcounting to them.
While at it, cleanup the "Proud member of Uglyhacks'R'US". It means,
define uart_handle_sysrq_char only when SUPPORT_SYSRQ is set.
Otherwise define it as a macro. This is needed for some arm driver
where the second parameter is undefined if expanded.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| d208a3bf77f902283894f546b6b5383202cf7882 |
|
19-Oct-2011 |
Doug Anderson <dianders@chromium.org> |
TTY: serial_core: Fix crash if DCD drop during suspend
This crash was showing up 100% of the time on Tegra CPUs when an
agetty was running on the serial port and the console was not running
on the serial port. The reason the Tegra saw it so reliably is that
the Tegra CPU internally ties DTR to DCD/DSR. That means when we
dropped DTR during suspend we would get always get an immediate DCD
drop.
The specific order of operations that were running:
* uart_suspend_port() would be called to put the uart in suspend mode
* we'd drop DTR (ops->set_mctrl(uport, 0)).
* the DTR drop would be looped back in the CPU to be a DCD drop.
* the DCD drop would look to the serial driver as a hangup
* the hangup would call uart_shutdown()
* ... suspend / resume happens ...
* uart_resume_port() would be called and run the code in the
(port->flags & ASYNC_SUSPENDED) block, which would startup the port
(and enable tx again).
* Since the UART would be available for tx, we'd immediately get
an interrupt, eventually calling transmit_chars()
* The transmit_chars() function would crash. The first crash would
be a dereference of a NULL tty member, but since the port has been
shutdown that was just a symptom.
I have proposed a patch that would fix the Tegra CPUs here (see
https://lkml.org/lkml/2011/10/11/444 - tty/serial: Prevent drop of DCD
on suspend for Tegra UARTs). However, even with that fix it is still
possible for systems that have an externally visible DCD line to see a
crash if the DCD drops at just the right time during suspend: thus
this patch is still useful.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 94abc56f4d90f289ea32a0a11d3577fcd8cb28fb |
|
05-Sep-2011 |
Ning Jiang <ning.jiang@marvell.com> |
serial-core: power up uart port early before we do set_termios when resuming
The following patch removed uart_change_pm() in uart_resume_port():
commit 5933a161abcb8d83a2c145177f48027c3c0a8995
Author: Yin Kangkai <kangkai.yin@linux.intel.com>
serial-core: reset the console speed on resume
It will break the pxa serial driver when the system resumes from suspend mode
as it will try to set baud rate divider register in set_termios but with
clock off. The register value can not be set correctly on some platform if
the clock is disabled. The pxa driver will check the value and report the
following warning:
------------[ cut here ]------------
WARNING: at drivers/tty/serial/pxa.c:545 serial_pxa_set_termios+0x1dc/0x250()
Modules linked in:
[<c0281f30>] (unwind_backtrace+0x0/0xf0) from [<c029341c>] (warn_slowpath_common+0x4c/0x64)
[<c029341c>] (warn_slowpath_common+0x4c/0x64) from [<c029344c>] (warn_slowpath_null+0x18/0x1c)
[<c029344c>] (warn_slowpath_null+0x18/0x1c) from [<c044b1e4>] (serial_pxa_set_termios+0x1dc/0x250)
[<c044b1e4>] (serial_pxa_set_termios+0x1dc/0x250) from [<c044a840>] (uart_resume_port+0x128/0x2dc)
[<c044a840>] (uart_resume_port+0x128/0x2dc) from [<c044bbe0>] (serial_pxa_resume+0x18/0x24)
[<c044bbe0>] (serial_pxa_resume+0x18/0x24) from [<c0454d34>] (platform_pm_resume+0x40/0x4c)
[<c0454d34>] (platform_pm_resume+0x40/0x4c) from [<c0457ebc>] (pm_op+0x68/0xb4)
[<c0457ebc>] (pm_op+0x68/0xb4) from [<c0458368>] (device_resume+0xb0/0xec)
[<c0458368>] (device_resume+0xb0/0xec) from [<c04584c8>] (dpm_resume+0xe0/0x194)
[<c04584c8>] (dpm_resume+0xe0/0x194) from [<c0458588>] (dpm_resume_end+0xc/0x18)
[<c0458588>] (dpm_resume_end+0xc/0x18) from [<c02c518c>] (suspend_devices_and_enter+0x16c/0x1ac)
[<c02c518c>] (suspend_devices_and_enter+0x16c/0x1ac) from [<c02c5278>] (enter_state+0xac/0xdc)
[<c02c5278>] (enter_state+0xac/0xdc) from [<c02c48ec>] (state_store+0xa0/0xbc)
[<c02c48ec>] (state_store+0xa0/0xbc) from [<c0408f7c>] (kobj_attr_store+0x18/0x1c)
[<c0408f7c>] (kobj_attr_store+0x18/0x1c) from [<c034a6a4>] (sysfs_write_file+0x108/0x140)
[<c034a6a4>] (sysfs_write_file+0x108/0x140) from [<c02fb798>] (vfs_write+0xac/0x134)
[<c02fb798>] (vfs_write+0xac/0x134) from [<c02fb8cc>] (sys_write+0x3c/0x68)
[<c02fb8cc>] (sys_write+0x3c/0x68) from [<c027c700>] (ret_fast_syscall+0x0/0x2c)
---[ end trace 88289eceb4675b04 ]---
This patch fix the problem by adding the power on opertion back for uart
console when console_suspend_enabled is true.
Signed-off-by: Ning Jiang <ning.jiang@marvell.com>
Tested-by: Mayank Rana <mrana@codeaurora.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 55956216f4b42fefaee70060b054359d63d2afa5 |
|
29-Aug-2011 |
Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com> |
TTY: serial: Move mutex_unlock in uart_close function
When mutex_lock is not called, mutex_unlock is sometimes called.
This deletes unnecessary goto and makes modifications so that
mutex_unlock is called.
[ 8.304000] WARNING: at kernel/muex-debug.c:78
[ 8.304000] Modules linked in:
[ 8.304000]
[ 8.304000] Pid : 114, Comm: modprobe
[ 8.304000] CPU : 0 Not tainted (3.1.0-rc3-next-20110826 #810)
[ 8.304000]
[ 8.304000] PC is at debug_mutex_unlock+0xf4/0x120
[ 8.304000] PR is at debug_mutex_unlock+0xe6/0x120
[ 8.304000] PC : 80051114 SP : 9f02de58 SR : 400081f1 TEA : 295cf4f2
[ 8.304000] R0 : 00000001 R1 : 00000000 R2 : 0000000f R3 : 00000000
[ 8.304000] R4 : 9fc63158 R5 : 00000000 R6 : 00000001 R7 : 9fe1de78
[ 8.304000] R8 : 805c6b2c R9 : 80003920 R10 : 00000000 R11 : 805c6b2c
[ 8.304000] R12 : 80425ca0 R13 : 00000000 R14 : 9f02de58
[ 8.304000] MACH: 00000003 MACL: 00000000 GBR : 296e1678 PR : 80051106
[ 8.304000]
[ 8.304000] Call trace:
[ 8.304000] [<804236c6>] __mutex_unlock_slowpath+0x46/0x120
[ 8.304000] [<804237aa>] mutex_unlock+0xa/0x20
[ 8.304000] [<80240ed6>] uart_close+0x76/0x2c0
[ 8.304000] [<80223b98>] tty_release+0xf8/0x5c0
[ 8.304000] [<800a93a6>] lookup_object+0x26/0xa0
[ 8.304000] [<80063f6a>] call_rcu+0x8a/0xc0
[ 8.304000] [<800a944a>] put_object+0x2a/0x60
[ 8.304000] [<80003920>] arch_local_irq_restore+0x0/0x40
[ 8.304000] [<800af320>] fput+0x180/0x2c0
[ 8.304000] [<800af248>] fput+0xa8/0x2c0
[ 8.304000] [<800ab1a8>] filp_close+0x48/0xc0
[ 8.304000] [<800ab29a>] sys_close+0x7a/0x100
[ 8.304000] [<8000825a>] syscall_call+0xc/0x10
[ 8.304000] [<800ab220>] sys_close+0x0/0x100
[ 8.304000]
[ 8.304000] Code:
[ 8.304000] 8005110e: mov.l @r1, r1
[ 8.304000] 80051110: tst r1, r1
[ 8.304000] 80051112: bf 80051116
[ 8.304000] ->80051114: trapa #62
[ 8.304000] 80051116: mov.l @r8, r1
[ 8.304000] 80051118: tst r1, r1
[ 8.304000] 8005111a: bt.s 8005104c
[ 8.304000] 8005111c: mov #0, r1
[ 8.304000] 8005111e: bra 80051056
[ 8.304000]
[ 8.304000] ---[ end trace e8f8e04c313f429b ]---
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 0b058353abfcdba4403af60f06998da590ebeffe |
|
25-Aug-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: use tty_wait_until_sent_from_close in other drivers
Let's use the newly added helper to avoid stalls in drivers which are
not yet ported to tty_port helpers.
Those which are broken (call tty_wait_until_sent with irqs disabled)
are left untouched. They are in a deeper trouble than we are trying to
solve here. This includes amiserial, 68328serial, 68360serial and
crisv10.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| bafb0bd24d7e0e0124318625b239a55d58c757a2 |
|
25-Aug-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, move locking in uart_close
So now, when we handle CLOSING flag, there is no point to hold
port->mutex over the start of uart_close.
Yes, there are still several things to reason about:
* port->count etc is and always was protected by a spinlock
* ->stop_rx is protected by a spinlock. Otherwise it would
race with interrupts.
* uart_wait_until_sent -- that one is already called without
port->mutex from set_termios and tty_set_ldisc. Should anything
be protected there, it would be tx_empty. And by a spinlock.
8250 does this internally...
This step is needed to fix system stalls. To not create an AB-BA lock
dependency (see next patches).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 426929f8d3514d7f727b8c464d1eeeaf74b21519 |
|
25-Aug-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, use ASYNCB_CLOSING in uart_close
We need to move port->mutex locking after wait_until_sent in
uart_close (for rationale see next patches). But if we did it now, we
would introduce a race between close and open. This is exactly why
port->mutex is locked at the top of uart_close.
To avoid the race, we add ASYNCB_CLOSING to uart_close. Like every
other sane TTY driver. Thanks to tty_port_block_til_ready used in
uart_open we will have this for free. Then we can move the port->mutex
lock.
Also note that this will make the conversion to tty_port helpers
easier. They are currently handling ASYNC_CLOSING flag correctly.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 4834d028978583dfe8e1fc19f1180ceb03d8dfb7 |
|
15-Aug-2011 |
Jamie Iles <jamie@jamieiles.com> |
tty: serial8250: remove UPIO_DWAPB{,32}
Now that platforms can override the port IRQ handler and the only user
of these UPIO modes has been converted over, kill off UPIO_DWAPB and
UPIO_DWAPB32.
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 906cbe1364d94da7cbf74c1d05e3e78b2883f661 |
|
14-Jul-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: remove tty_locked
We used it really only serial and ami_serial. The rest of the
callsites were BUG/WARN_ONs to check if BTM is held. Now that we
pruned tty_locked from both of the real users, we can get rid of
tty_lock along with __big_tty_mutex_owner.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 6a3e492b6daaf7ec4dc41e51d87d2aae8ff886f2 |
|
14-Jul-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, remove tasklet for tty_wakeup
tty_wakeup can be called from any context. So there is no need to have
an extra tasklet for calling that. Hence save some space and remove
the tasklet completely.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 1f33a51d9771b34be3cb6f7fb96a325e17bbac7b |
|
14-Jul-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, remove BTM from wait_until_sent
During the BKL removal process, the BKL was switched to tty_lock
(BTM). Now we should start pruning the BTM further. Let's start with
wait_until_sent of the serial layer. This will allow us to switch to
the tty port helpers and thus clean it up much.
In wait_until_sent there are some uport members accessed, but neither
of them is protected by BTM at the location they are set ('=>' means
function call):
* uport->fifosize (set in tty_ioctl => uart_ioctl => uart_set_info)
* uport->type (set in add_one_port prior to tty_register_device)
* uport->timeout (set usually in tty_ioctl => tty_mode_ioctl =>
tty_set_termios => uart_set_termios => uart_change_speed =>
uport->ops->set_termios => uart_update_timeout)
* call to uport->ops->tx_empty()
If the tx_empty hook needs some lock to protect accesses to registers,
it should take &uport->lock spinlock like 8250 does. Otherwise there
still might be races e.g. with ISRs.
This should also fix the issue Andreas is seeing (BTM in comparison to
BKL doesn't have any hidden functionality like unlocking during
sleeping).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
References: https://lkml.org/lkml/2011/5/25/562
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andreas Bombe <aeb@debian.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 0055197e984e5fbe6f48f37fc50dd30254915493 |
|
17-Aug-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial, document ignoring of uart->ops->startup error
When a user has SYS_ADMIN capabilities and uart->ops->startup returns
an error in uart_startup, we silently drop the error. We then return 0
and behave as if it didn't fail. (Not quite, since we set TTY_IO_ERROR
bit and leave ASYNC_INITIALIZED bit cleared.)
This all is to allow setserial to work with improperly configured or
unconfigured ports. User can thus set port properties and reconfigure
properly.
This patch only documents this behavior.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Russel King <linux@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| c831cff256c86588976e66bef7897633d534846c |
|
20-Apr-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial_core, remove superfluous set_task_state
msleep* is guaranteed to return with TASK_RUNNING task state. And
since there is no other set_task_state in the paths of
uart_wait_until_sent, we need not to set_task_state to TASK_RUNNING.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 32ad3a77b256948a326c3f68db6acaad2b6953e7 |
|
20-Apr-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial_core, remove invalid test
tty->index (named here as line) is set up in initialize_tty_struct.
The value is checked in get_tty_driver for the found driver as:
if (device < base || device >= base + p->num)
continue;
*index = device - base;
So index/line can never be more than driver->num. Hence remove this
test from uart_open.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| e9a470f445271eb157ee860a93b062324402fc3a |
|
18-Apr-2011 |
Govindraj.R <govindraj.raja@ti.com> |
Serial: Remove unused code.
Remove stale code in serial_core layer.
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Govindraj.R <govindraj.raja@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 99edb3d10a9d384d69557bd09cc39b9ec62aa04e |
|
30-Mar-2011 |
Jovi Zhang <bookjovi@gmail.com> |
tty: remove invalid location line in file header
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>
|
| 6f5c24ad0f7619502199185a026a228174a27e68 |
|
30-Mar-2011 |
Jiri Slaby <jslaby@suse.cz> |
serial: core, remove uart_update_termios
Now, uart_update_termios is empty, so it's time to remove it. We no
longer need a live tty in .dtr_rts. So this should prune all the bugs
where tty is zeroed in port->tty during tty_port_block_til_ready.
There is one thing to note. We don't set ASYNC_NORMAL_ACTIVE now. It's
because this is done already in tty_port_block_til_ready.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 303a7a1199c20f7c9452f024a6e17bf348b6b398 |
|
30-Mar-2011 |
Jiri Slaby <jslaby@suse.cz> |
serial: core, do not set DTR/RTS twice on startup
In .dtr_rts we do:
uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS)
and call uart_update_termios. It does:
uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS)
once again. As the only callsite of uart_update_termios is .dtr_rts,
remove the uart_set_mctrl from uart_update_termios to not set it twice.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| c7d7abff40c27f82fe78b1091ab3fad69b2546f9 |
|
30-Mar-2011 |
Jiri Slaby <jslaby@suse.cz> |
serial: core, move termios handling to uart_startup
We should not fiddle with speed and cflags in .dtr_rts hook. Actually
we might not have tty at that moment already.
So move the console cflag copy and speed setup into uart_startup.
Actually the speed setup is already there, but we need to call it
unconditionally (uart_startup is called from uart_open with hw_init =
0).
This means we move uart_change_speed before dtr/rts setup in .dtr_rts.
But this should not matter as the setup should be called after
uart_change_speed anyway.
Before: After:
dtr/rts setup (dtr_rts) uart_change_speed (startup)
uart_change_speed (update_termios) dtr/rts setup (dtr_rts)
dtr/rts setup (update_termios) dtr/rts setup (update_termios)
The second setup will dismiss with the next patch.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 4fd53ef5c97ef7ce909c18bf7fb8b5cdd72b08c1 |
|
23-Mar-2011 |
Jiri Slaby <jslaby@suse.cz> |
TTY: serial_core, remove unused variable
drivers/tty/serial/serial_core.c:1980:2: warning: Value stored to 'tty' is never read
tty = port->tty;
^ ~~~~~~~~~
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Govindraj.R <govindraj.raja@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 6caa76b7786891b42b66a0e61e2c2fff2c884620 |
|
14-Feb-2011 |
Alan Cox <alan@linux.intel.com> |
tty: now phase out the ioctl file pointer for good
Only oddities here are a couple of drivers that bogusly called the ldisc
helpers instead of returning -ENOIOCTLCMD. Fix the bug and the rest goes
away.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 20b9d17715017ae4dd4ec87fabc36d33b9de708e |
|
14-Feb-2011 |
Alan Cox <alan@linux.intel.com> |
tiocmset: kill the file pointer argument
Doing tiocmget was such fun we should do tiocmset as well for the same
reasons
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 60b33c133ca0b7c0b6072c87234b63fee6e80558 |
|
14-Feb-2011 |
Alan Cox <alan@linux.intel.com> |
tiocmget: kill off the passing of the struct file
We don't actually need this and it causes problems for internal use of
this functionality. Currently there is a single use of the FILE * pointer.
That is the serial core which uses it to check tty_hung_up_p. However if
that is true then IO_ERROR is also already set so the check may be removed.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| 5933a161abcb8d83a2c145177f48027c3c0a8995 |
|
30-Jan-2011 |
Yin Kangkai <kangkai.yin@linux.intel.com> |
serial-core: reset the console speed on resume
On some platforms, we need to restore the console speed on resume even
it was not suspended (no_console_suspend), and on others we don't have
to do that.
So don't care about the "console_suspend_enabled" and unconditionally
reset the console speed if it is a console.
This is actually a redo of ba15ab0 (Set proper console speed on resume
if console suspend is disabled) from Deepak Saxena. I also tried to
investigate more to find out if this change will break others, here is
what I've found out:
commit 891b9dd10764352926e1e107756aa229dfa2c210
Author: Jason Wang <jason77.wang@gmail.com>
serial-core: restore termios settings when resume console ports
commit ca2e71aa8cfb0056ce720f3fd53f59f5fac4a3e1
Author: Jason Wang <jason77.wang@gmail.com>
serial-core: skip call set_termios/console_start when no_console_suspend
commit 4547be7809a3b775ce750ec7f8b5748954741523
Author: Stanislav Brabec <sbrabec@suse.cz>
serial-core: resume serial hardware with no_console_suspend
commit ba15ab0e8de0d4439a91342ad52d55ca9e313f3d
Author: Deepak Saxena <dsaxena@laptop.org>
Set proper console speed on resume if console suspend is disabled
from ba15ab0, we learned that, even if the console suspend is disabled
(when no_console_suspend is set), we may still need to "reset the port
to the state it was in before we suspended."
Then with 4547be7, this piece of code is removed.
And then Jason Wang added that back in ca2e71a and 891b9dd, to fix
some breakage on OMAP3EVM platform. From ca2e71a we learned that the
"set_termios" things is actually needed by both console is suspended
and not suspended.
That's why I removed the console_suspended_enabled condition, and only
call console_start() when we actually suspeneded it.
I also noticed in this thread:
http://marc.info/?t=129079257100004&r=1&w=2, which talked about on
some platforms, UART HW will be cut power whether or not we set
no_console_suspend, and then on resume it does not work quite well. I
have a similar HW, and this patch fixed this issue, don't know if this
patch also works on their platforms.
[Update: Stanislav tested this patch on Zaurus and reported it improves the
situation. Thanks.]
CC: Greg KH <greg@kroah.com>
CC: Deepak Saxena <dsaxena@laptop.org>
CC: Jason Wang <jason77.wang@gmail.com>
CC: Stanislav Brabec <sbrabec@suse.cz>
CC: Daniel Drake <dsd@laptop.org>
Signed-off-by: Yin Kangkai <kangkai.yin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
| ab4382d27412e7e3e7c936e8d50d8888dfac3df8 |
|
13-Jan-2011 |
Greg Kroah-Hartman <gregkh@suse.de> |
tty: move drivers/serial/ to drivers/tty/serial/
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>
|