Commit Graph

1237 Commits

Author SHA1 Message Date
Alan Cox
d1519e23c2 ipwireless: don't oops if we run out of space
Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=49851

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 16:53:15 -08:00
Alan Cox
4bd82136cd moxa: dcd handling of CLOCAL is backwards
We should do hangup on dcd loss if CLOCAL is false not true.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=49911
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 16:53:14 -08:00
Jun Chen
e8823f1ca8 serial: ifx6x60: ifx_spi_write don't need to do mrdy_assert when fifo is not empty
This patch check whether the fifo lenth is empty before writing new data to fifo.If condition
is true,ifx_spi_write need to trigger one mrdy_assert. If condition is false,the mrdy_assert
will be trigger by the next ifx_spi_io.

Cc: Bi Chao <chao.bi@intel.com>
Signed-off-by: Chen Jun <jun.d.chen@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 16:51:38 -08:00
chao bi
1b2f8a9550 serial:ifx6x60:SPI header is decoded incorrectly
This patch is to correct the bit mapping of "MORE" and "CTS" in SPI frame header.
Per SPI protocol, SPI header is encoded with length of 4 byte, which is defined
as below:
bit 0 ~ 11: current data size;
bit 12: "MORE" bit;
bit 13: reserve
bit 14 ~ 15: reserve
bit 16 ~ 27: next data size
bit 28: RI
bit 29: DCD
bit 30: CTS/RTS
bit 31: DSR/DTR

According to above SPI header structure, the bit mapping of "MORE" and "CTS" is
incorrect in function ifx_spi_decode_spi_header();

Cc: Chen Jun <jun.d.chen@intel.com>
Signed-off-by: channing <chao.bi@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 16:47:35 -08:00
Wei Yongjun
76cc43868c tty: of_serial: fix return value check in of_platform_serial_setup()
In case of error, the function clk_get() returns ERR_PTR()
and never returns NULL. The NULL test in the return value
check should be replaced with IS_ERR().

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-01 08:50:01 -07:00
chao bi
31fe990488 serial:ifx6x60:Prevent data transfer when IFX6x60 port is shutdown
This patch is to implement following 2 places to avoid potential error when IFX6x60 port shutdown:
1) Clear Flag IFX_SPI_STATE_IO_AVAILABLE to disable data transfer when Modem port is shutdown;
2) Clear Flag IFX_SPI_STATE_IO_IN_PROGRESS and IFX_SPI_STATE_IO_READY when reopen port.
This is because last port shutdown may happen when SPI/DMA transfer is in progress, if the last
data transfer is not completed(for example due to modem reset), the Flag IFX_SPI_STATE_IO_IN_PROGRESS
will be set forever, so when IFX port is activated again, IFX_SPI_STATE_IO_IN_PROGRESS will prevent
transferring data forever. And if don't clear IFX_SPI_STATE_IO_READY, it may cause one more SPI frame
transferring in spit there is not data need to be transfer.

cc: liu chuansheng <chuansheng.liu@intel.com>
cc: Chen Jun <jun.d.chen@intel.com>
Signed-off-by: channing <chao.bi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-01 08:50:01 -07:00
Vineet Gupta
2ac4ad2a14 serial/arc-uart: Add new driver
Driver for non-standard on-chip UART, instantiated in the ARC (Synopsys)
FPGA Boards such as ARCAngel4/ML50x

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-30 14:06:52 -07:00
Alan Cox
373bac4cf4 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>
2012-10-30 14:05:32 -07:00
Alan Cox
9f1096943a 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>
2012-10-30 14:05:31 -07:00
Alan Cox
bebe73e31d 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>
2012-10-30 14:05:31 -07:00
Wei Yongjun
15a12e83da serial: 8250_pci: use module_pci_driver to simplify the code
Use the module_pci_driver() macro to make the code simpler
by eliminating module_init and module_exit calls.

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-30 14:04:52 -07:00
Joe Perches
669fef4644 serial: jsm: Convert jsm_printk to jsm_dbg
These printks should all be emitted at KERN_DEBUG level.
Make them dependent on CONFIG_DEBUG or (#define DEBUG)
simplify the code a bit.

Add missing newlines where appropriate.

Most all of these messages could be deleted too.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-30 14:04:52 -07:00
Greg Kroah-Hartman
ca364d8388 Merge 3.7-rc3 into tty-next
This merges the tty changes in 3.7-rc3 into tty-next

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-29 09:00:57 -07:00
Cyrill Gorcunov
84fd7bdf12 tty: Add get- ioctls to fetch tty status v3
For checkpoint/restore we need to know if tty has
exclusive or packet mode set, as well as if pty
is currently locked. Just to be able to restore
this characteristics.

For this sake the following ioctl codes are introduced

 - TIOCGPKT to get packet mode state
 - TIOCGPTLCK to get Pty locked state
 - TIOCGEXCL to get Exclusive mode state

Note this ioctls are a bit unsafe in terms of data
obtained consistency. The tty characteristics might
be changed right after ioctl complete. Keep it in
mind and use this ioctl carefully.

v2:
 - Use TIOC prefix for ioctl codes (by jslaby@)

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: Alan Cox <alan@lxorguk.ukuu.org.uk>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Pavel Emelyanov <xemul@parallels.com>
CC: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 12:07:18 -07:00
Cyrill Gorcunov
06026d911c tty: pty - Move TIOCPKT handling into pty.c
Since this ioctl is for pty devices only move it to pty.c.

v2:
 - drop PTY_TYPE_MASTER test since it's master peer
   ioctl anyway (by jslaby@)

Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Pavel Emelyanov <xemul@parallels.com>
CC: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 12:07:18 -07:00
Murali Karicheri
0bbeb3c3e8 of serial port driver - add clk_get_rate() support
Currently this driver expects the clock-frequency attribute. This
patch allows getting clock-frequency through clk driver API
clk_get_rate() if clock-frequency attribute is not defined.

So in the device bindings for serial device, one can add clocks
phandle to refer to the clk device to get the rate.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 11:32:29 -07:00
Sasha Levin
cadf748690 tty: add missing newlines to WARN_RATELIMIT
WARN_RATELIMIT() expects the warning to end with a newline if one
is needed.

Not doing so results in odd looking warnings such as:

[ 1339.454272] tty is NULLPid: 7147, comm: kworker/4:0 Tainted: G        W    3.7.0-rc2-next-20121025-sasha-00001-g673f98e-dirty #75

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 11:30:27 -07:00
Jun Chen
2e30802625 serial: ifx6x60: del_timer_sync must not be called in interrupt context.
This patch make use of del_timer instead of del_timer_sync in the
interrupt context.
The spi_timer function don't use any resources that may release after
running del_timer,
so using the del_timer is also safe and enough in this context.

Signed-off-by: Chen Jun <jun.d.chen@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Tested-by: Chuansheng Liu <chuansheng.liu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 11:29:58 -07:00
Jun Chen
c73ba2ae43 serial: ifx6x60: add_timer is not safe in the mrdy_assert function
This patch make use of mod_timer instead of add_timer in the mrdy_assert function.
Because the srdy interrupter can go high when we are running function mrdy_assert and mrdy_assert
can be called by multi-entry. In our medfield platform, spi stress test can encounter this
error logs triggered by the BUG_ON of add_timer function.This patch had been tested on
our medfield platform.

the scenario:
      CPU0							CPU1
mrdy_assert
set_bit(IFX_SPI_STATE_TIMER_PENDING)
								ifx_spi_handle_srdy
								...
								clear_bit(IFX_SPI_STATE_TIMER_PENDING)
								...
								mrdy_assert
								set_bit(IFX_SPI_STATE_TIMER_PENDING)
								...
								add_timer
...
add_timer

Cc: liu chuansheng <chuansheng.liu@intel.com>
Cc: Bi Chao <chao.bi@intel.com>
Signed-off-by: Chen Jun <jun.d.chen@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 11:29:58 -07:00
chao bi
319fb0d219 serial: ifx6x60: different SPI word width configure requires different swap process
SPI protocol driver only provide one function (swap_buf()) to swap SPI
data into big endian format, which is only available when SPI
controller's word width is 16 bits. But word width could be configured
as 8/16/32 bits, different word width configure should be mapped to
different swap methods.This patch is to make SPI protocol driver choose
the right swap function corresponding to SPI word width configuration.

cc: liu chuansheng <chuansheng.liu@intel.com>
cc: Chen Jun <jun.d.chen@intel.com>
Signed-off-by: channing <chao.bi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 11:29:58 -07:00
Linus Walleij
de60958207 serial/amba-pl011: use devm_* managed resources
This switches a bunch of allocation and remapping to use the
devm_* garbage collected methods and cleans up the error
path and remove() paths consequently.

devm_ioremap() is only in <linux/io.h> so fix up the
erroneous <asm/*> include as well.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Domenico Andreoli <domenico.andreoli@linux.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 11:29:44 -07:00
Shubhrajyoti D
40477d0e04 serial: omap: Remove the hardcode serial_omap_console_ports array.
Currently the array serial_omap_console_ports is hard coded to 4.
Make it depend on the maximum uart count.
Post to [cfc55bc ARM: OMAP2+: serial: Change MAX_HSUART_PORTS to 6]
the max ports is 6.

Cc: AnilKumar Ch <anilkumar@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 11:29:11 -07:00
Shubhrajyoti D
7ba897d77c serial: omap: Remove the default setting of special character
Special character detect enable if enabled by default.Received data
comparison with XOFF2 data happens by default.

tty provides only XOFF1 no X0FF2 is provided so no need
to enable check for XOFF2.

Keeping this enabled might give some slow transfers due to dummy xoff2
comparison with xoff2 reset value.

Since not all want the XOFF2 support lets not enable it by
default.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 11:29:11 -07:00
Shubhrajyoti D
39aee51d43 serial: omap: Make context_loss_cnt signed
get_context_loss_count returns an int however it is stored in
unsigned integer context_loss_cnt . This patch tries to make
context_loss_cnt int. So that in case of errors the value
(which may be negative) is not interpreted wrongly.

In serial_omap_runtime_resume in case of errors returned by
get_context_loss_count print a warning and do a restore.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 11:29:10 -07:00
Felipe Balbi
a4f743851f Revert "serial: omap: fix software flow control"
This reverts commit 957ee7270d
(serial: omap: fix software flow control).

As Russell has pointed out, that commit isn't fixing
Software Flow Control at all, and it actually makes
it even more broken.

It was agreed to revert this commit and use Russell's
latest UART patches instead.

Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:57:21 -07:00
Alexander Shiyan
a1c25f2b98 serial: clps711x: Cleanup driver
This patch performs cleanup on clps711x serial driver. This include:
- Change functions naming style.
- Removed unused includes.
- Removed unneeded comments.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:48 -07:00
Alexander Shiyan
7ae75e94ec serial: clps711x: Fix TERMIOS-flags handling
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:48 -07:00
Alexander Shiyan
f52ede2ac1 serial: clps711x: Disable "break"-state before port startup
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:48 -07:00
Alexander Shiyan
135cc79035 serial: clps711x: Using resource-managed functions
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:48 -07:00
Alexander Shiyan
f27de95c2a serial: clps711x: Check for valid TTY in RX-interrupt
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:48 -07:00
Alexander Shiyan
ec335526b4 serial: clps711x: Fix break control handling
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:47 -07:00
Alexander Shiyan
1593daf9a8 serial: clps711x: Return valid modem controls for port that not support it
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:47 -07:00
Alexander Shiyan
cf03a884b9 serial: clps711x: Improved TX FIFO handling
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:47 -07:00
Alexander Shiyan
c08f0153f5 serial: clps711x: Using CPU clock subsystem for getting base UART speed
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:47 -07:00
Alexander Shiyan
3c7e9eb160 serial: clps711x: Do not use "uart_port->unused" field
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:47 -07:00
Alexander Shiyan
117d5d424a serial: clps711x: Convert all static variables to dynamic
This patch converts all static variables of clps711x serial driver
to dynamic allocating. In this case we are should remove console_initcall()
and declare console during driver registration. Early kernel messages can
be retrieved by add "earlyprintk" option to the kernel command line.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:47 -07:00
Alexander Shiyan
95113728f0 serial: clps711x: Add platform_driver interface to clps711x driver
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:39:47 -07:00
Denis V. Lunev
e1a9c17969 tty: serial: KGDB support for PXA
Actually, in order to support KGDB over serial console one must
implement two callbacks for character polling. Clone them from
8250 driver with a bit of tuning.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Marko Katic <dromede@gmail.com>
CC: Eric Miao <eric.y.miao@gmail.com>
CC: Russell King <linux@arm.linux.org.uk>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>

 drivers/tty/serial/pxa.c |   55 ++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 55 insertions(+), 0 deletions(-)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:38:28 -07:00
Ivo Sieben
c97399418a tty: Use raw spin lock to protect TTY ldisc administration
The global "normal" spin lock that guards the line discipline
administration is replaced by a raw spin lock. On a PREEMPT_RT system this
prevents unwanted scheduling overhead around the line discipline administration.

On a 200 MHz AT91SAM9261 processor setup this fixes about 100us of scheduling
overhead on a TTY read or write call.

Signed-off-by: Ivo Sieben <meltedpianoman@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:37:02 -07:00
Wei Yongjun
ad3d1e5fc9 TTY: hvcs: fix missing unlock on error in hvcs_initialize()
Add the missing unlock on the error handling path in function
hvcs_initialize().

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:37:02 -07:00
Maxime Bizon
08ec212c0f x86: ce4100: allow second UART usage
The current CE4100 and 8250_pci code have both a limitation preventing the
registration and usage of CE4100's second UART. This patch changes the
platform code fixing up the UART port to work on a relative UART port
base address, as well as the 8250_pci code to make it register 2 UART ports
for CE4100 and pass the port index down to all consumers.

Signed-off-by: Florian Fainelli <ffainelli@freebox.fr>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:34:51 -07:00
Sangho Yi
7a0c4edae9 tty: tty_mutex.c: Fixed coding style warning (using printk)
Here I fixed from printk(KERN_ERR, ... to pr_err(... on tty_mutex.c

Signed-off-by: Sangho Yi <antiroot@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:34:51 -07:00
James Hogan
b61c5ed571 tty: serial: 8250_dw: Implement suspend/resume
Implement suspend and resume callbacks for DesignWare 8250 driver.
They're simple wrappers around serial8250_{suspend,resume}_port.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:34:51 -07:00
Wei Yongjun
59c2e855e4 serial: vt8500: fix possible memory leak in vt8500_serial_probe()
vt8500_port is malloced in vt8500_serial_probe() and should be freed
before leaving from the error handling cases, otherwise it will
cause memory leak.
Fix it by move the allocation of vt8500_port after those test.

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:34:51 -07:00
Tony Lindgren
54ec52b6dd tty/serial/8250: Make omap hardware workarounds local to 8250.h
This allows us to get rid of the ifdefs in 8250.c.

Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:30:57 -07:00
Alexey Brodkin
b15d5380e4 serial/8250/8250_early: Prevent rounding error in uartclk
Modify divisor to select the nearest baud rate divider rather than the
lowest. It minimizes baud rate errors especially on low UART clock
frequencies.

For example, if uartclk is 33000000 and baud is 115200 the ratio is
about 17.9 The current code selects 17 (5% error) but should select 18
(0.5% error).

This 5% error in baud rate leads to garbage on receiving end, while 0.5%
doesn't.

The issue showed up when using the stock 8250 driver for
Synopsys DW UART. This was on a FPGA with ~12MHz UART clock.
When we enabled early serial, we saw garbage which was narrowed down
to the rounding error.

So the bug had been latent and it only showed up with such low clock rates.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:29:30 -07:00
Thomas Abraham
9484b009b5 serial: samsung: use clk_prepare_enable and clk_disable_unprepare
Convert clk_enable/clk_disable to clk_prepare_enable/clk_disable_unprepare
calls as required by common clock framework.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:29:30 -07:00
Ivo Sieben
b8b345bae8 TTY: Report warning when low_latency flag is wrongly used
When a driver has the low_latency flag set and uses the schedule_flip()
function to initiate copying data to the line discipline, a workqueue is
scheduled in but never actually flushed. This is incorrect use of the
low_latency flag (driver should not support the low_latency flag, or use
the tty_flip_buffer_push() function instead). Make sure a warning is
reported to catch incorrect use of the low_latency flag.

This patch goes with: cee4ad1ed9

Signed-off-by: Ivo Sieben <meltedpianoman@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 11:21:32 -07:00
Jiri Slaby
ecbbfd44a0 TTY: move tty buffers to tty_port
So this is it. The big step why we did all the work over the past
kernel releases. Now everything is prepared, so nothing protects us
from doing that big step.

           |  |            \  \ nnnn/^l      |  |
           |  |             \  /     /       |  |
           |  '-,.__   =>    \/   ,-`    =>  |  '-,.__
           | O __.´´)        (  .`           | O __.´´)
            ~~~   ~~          ``              ~~~   ~~
The buffers are now in the tty_port structure and we can start
teaching the buffer helpers (insert char/string, flip etc.) to use
tty_port instead of tty_struct all around.

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>
2012-10-22 16:58:28 -07:00
Jiri Slaby
967fab6916 TTY: add port -> tty link
For that purpose we have to temporarily introduce a second tty back
pointer into tty_port. It is because serial layer, and maybe others,
still do not use tty_port_tty_set/get. So that we cannot set the
tty_port->tty to NULL at will now.

Yes, the fix would be to convert whole serial layer and all its users
to tty_port_tty_set/get. However we are in the process of removing the
need of tty in most of the call sites, so this would lead to a
duplicated work.

Instead we have now tty_port->itty (internal tty) which will be used
only in flush_to_ldisc. For that one it is ensured that itty is valid
wherever the work is run. IOW, the work is synchronously cancelled
before we set itty to NULL and also before hangup is processed.

After we need only tty_port and not tty_struct in most code, this
shall be changed to tty_port_tty_set/get and itty removed completely.

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>
2012-10-22 16:53:40 -07:00