Commit graph

1031 commits

Author SHA1 Message Date
Russell King
6920b5a791 ARM: move serial_sa1100.h header file to linux/platform_data
This is really driver platform data, so move it to the appropriate
directory.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-16 11:35:29 +00:00
Shinya Kuribayashi
33b48e1633 serial: sh-sci: fix possible race cases on SCSCR register accesses
In the previous commit, console write function (serial_console_write)
is changed to disable SCI interrupts while printing console strings.
This introduces possible race cases in the serial startup / shutdown
functions on SMP systems.

This patch fixes the sh-sci in the same way as commit 9ec1882df2
(tty: serial: imx: console write routing is unsafe on SMP, from
Xinyu Chen <xinyu.chen@freescale.com>, 2012-08-27) did.

There could be several consumers of the console,
* the kernel printk
* the init process using /dev/kmsg to call printk to show log
* shell, which opens /dev/console and writes with sys_write()

The shell goes into the normal UART open() and write() system calls,
while the other two go into the console operations.  The open() call
invokes serial startup function (sci_startup), which will write to
the SCSCR register (to enable or disable SCI interrupts) without any
locking.  This will conflict with the console serial function.

Add spinlock protections in sci_startup() and sci_shutdown() properly.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 18:02:51 -08:00
Shinya Kuribayashi
40f70c03e3 serial: sh-sci: add locking to console write function to avoid SMP lockup
Symptom:

When entering the suspend with Android logcat running, printk() call
gets stuck and never returns.  The issue can be observed at printk()s
on nonboot CPUs when going to offline with their interrupts disabled,
and never seen at boot CPU (core0 in our case).

Details:

serial_console_write() lacks of appropriate spinlock handling.

In SMP systems, as long as sci_transmit_chars() is being processed
at one CPU core, serial_console_write() can stuck at the other CPU
core(s), when it tries to access to the same serial port _without_
a proper locking.  serial_console_write() waits for the transmit FIFO
getting empty, while sci_transmit_chars() writes data to the FIFO.

In general, peripheral interrupts are routed to boot CPU (core0) by
Linux ARM standard affinity settings.  SCI(F) interrupts are handled
by core0, so sci_transmit_chars() is processed on core0 as well.

When logcat is running, it writes enormous log data to the kernel at
every moment, forever.  So core0 can repeatedly continue to process
sci_transmit_chars() in its interrupt handler, which eventually makes
the other CPU core(s) stuck at serial_console_write().

Looking at serial/8250.c, this is a known console write lockup issue
with SMP kernels.  Fix the sh-sci driver in the same way 8250.c does.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 18:02:51 -08:00
Takashi Yoshii
8c66d6d2a1 serial: sh-sci: fix common SCIFB regmap definition
About FIFO count, there are two variants of SCIFs which show
a) TX count in upper, RX count in lower byte of FDR register
b) TX count in TFDR register, RX count in RFDR register

Common SCIFB regmap in current source code is defined as "a".
At least 7372 and 73a0 HW manual say their SICFB are "b".

This patch alters the definition to "b", considering the current
one has come from a mistake. The reason is as follows.

The flag SCIFB sh-sci driver means it has 256 byte FIFO.
The count is from 0(empty) to 256(full), that makes 9-bit.
Because FDR is 16-bit register, it can not hold two 9-bits.
That's why, SCIFB can not be "a".

Signed-off-by: Takashi Yoshii <takashi.yoshii.zj@renesas.com>
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 18:02:51 -08:00
Takashi Yoshii
63f7ad115e serial: sh-sci: mask SCTFDR/RFDR according to fifosize
Current mask 0xff to SCTFDR/RFDR damages SCIFB, because the
registers on SCIFB have 9-bit data (0 to 256).

This patch changes the mask according to port->fifosize.
Though I'm not sure if the mask is really needed (I don't know if
there are variants which have non-zero upper bits), it is safer.

Signed-off-by: Takashi Yoshii <takashi.yoshii.zj@renesas.com>
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 18:02:37 -08:00
Takashi Yoshii
9d482cc353 serial: sh-sci: support lower baud rate
Support prescaler 1/16 and 1/64, in addition to current 1 and 1/4.

Supporting below 2400bps was dropped long time ago in mainline.
Since then, setting lower rate has been resulting in erroneous
register value, without indicating any errors through API.

This patch adds more prescaler to support lower rates again.
This still doesn't check range, but we won't hit the case because
even 50bps at 48MHz clock is now supported.

Signed-off-by: Takashi Yoshii <takashi.yoshii.zj@renesas.com>
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 18:02:37 -08:00
Takashi Yoshii
4ffc3cdb64 serial: sh-sci: fix condition test to set SCBRR
SCBRR == 0 is valid value (divide by 1).

Signed-off-by: Takashi Yoshii <takashi.yoshii.zj@renesas.com>
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 18:02:37 -08:00
Teppei Kamijou
0174e5ca82 serial: sh-sci: console runtime PM support (revisit)
The commit 1ba7622094 (serial: sh-sci: console Runtime PM support,
from Magnus Damm <damm@opensource.se>, 2011-08-03), tried to support
console runtime PM, but unfortunately it didn't work for us for some
reason.  We did not investigated further at that time, instead would
like to propose a different approach.

In Linux tty/serial world, to get console PM work properly, a serial
client driver does not have to maintain .runtime_suspend()/..resume()
calls itself, but can leave console power power management handling to
the serial core driver.

This patch moves the sh-sci driver in that direction.

Notes:

* There is room to optimize console runtime PM more aggressively by
  maintaining additional local runtime PM calls, but as a first step
  having .pm() operation would suffice.

* We still have a couple of direct calls to sci_port_enable/..disable
  left in the driver.  We have to live with them, because they're out
  of serial core's help.

Signed-off-by: Teppei Kamijou <teppei.kamijou.yb@renesas.com>
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 18:02:36 -08:00
Shinya Kuribayashi
00cadbfd1e Partially revert "serial: sh-sci: console Runtime PM support"
This partially reverts commit 1ba7622094 (serial: sh-sci: console
Runtime PM support, from Magnus Damm <damm@opensource.se>, 2011-08-03).

The generic 'serial_core' can take care of console PM maintenance,
so all (or at least the first thing) we have to do to get console PM
work properly, is to implement uart_ops ->pm() operation in the sh-sci
serial client driver.

This patch partially reverts the commit above, but leaving sci_reset()
change in place, because sci_reset() is already part of another commit
(73c3d53f38 serial: sh-sci: Avoid FIFO clear for MCE toggle.).

A revised version of console PM support follows next.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 18:02:36 -08:00
Shinya Kuribayashi
8807ec6c70 Revert "sh-sci / PM: Use power.irq_safe"
This reverts commit 5a50a01bf0 (sh-sci / PM: Use power.irq_safe, from
Rafael J. Wysocki <rjw@sisk.pl>, 2011-08-24).

In order to get console PM work properly, we should implement uart_ops
->pm() operation, rather than sprinkle band-ading runtime PM calls in
the driver.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 18:02:04 -08:00
Shinya Kuribayashi
cee31c52df Revert "sh-sci / PM: Avoid deadlocking runtime PM"
This reverts commit 048be431e4 (sh-sci / PM: Avoid deadlocking runtime
PM, from Rafael J. Wysocki <rjw@sisk.pl>, 2012-03-09).

In order to get console PM work properly, we should implement uart_ops
->pm() operation, rather than sprinkle band-ading runtime PM calls in
the driver.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 18:02:04 -08:00
Jiri Slaby
191c5f1027 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>
2012-11-15 17:20:58 -08:00
Gabor Juhos
2dff8ad926 tty/serial/ar933x_uart: fix baud rate calculation
The UART of the AR933x SoC implements a fractional divisor
for generating the desired baud rate.

The current code uses a fixed value for the fractional
part of the divisor, and this leads to improperly
calculated baud rates:

   baud    scale   step  real baud         diff
     300   5207*   8192     17756     17456   5818.66%
     600   2603*   8192     35511     34911   5818.50%
    1200   1301*   8192     71023     69823   5818.58%
    2400    650*   8192     11241      8841    368.37%
    4800    324*   8192     22645     17845    371.77%
    9600    161    8192      9645        45      0.46%
   14400    107    8192     14468        68      0.47%
   19200     80    8192     19290        90      0.46%
   28800     53    8192     28935       135      0.46%
   38400     39    8192     39063       663      1.72%
   57600     26    8192     57870       270      0.46%
  115200     12    8192    120192      4992      4.33%
  230400      5    8192    260417     30017     13.02%
  460800      2    8192    520833     60033     13.02%
  921600      0    8192   1562500    640900     69.93%

After the patch, the integer and fractional parts of the
divisor will be calculated dynamically. This ensures that
the UART will use correct baud rates:

   baud    scale   step  real baud         diff
     300      6      11       300         0      0.00%
     600     54     173       600         0      0.00%
    1200     30     195      1200         0      0.00%
    2400     30     390      2400         0      0.00%
    4800     48    1233      4800         0      0.00%
    9600     78    3976      9600         0      0.00%
   14400     98    7474     14400         0      0.00%
   19200     55    5637     19200         0      0.00%
   28800    130   19780     28800         0      0.00%
   38400     36    7449     38400         0      0.00%
   57600     78   23857     57600         0      0.00%
  115200     43   26575    115200         0      0.00%
  230400     23   28991    230400         0      0.00%
  460800     11   28991    460800         0      0.00%
  921600      5   28991    921599        -1      0.00%

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 17:15:02 -08:00
Alexander Shiyan
18e0749aa8 serial: Unneeded ARCH dependencies are removed
This patch performs a small cleanup tty/Serial/Kconfig file by removing
unneeded ARCH dependencies. This dependencies already included in
board/type symbols.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 17:11:42 -08:00
Feng Tang
50827fbde1 serial: mfd: Add nmi_touch_watchdog() into the console write function
This is following what 8250 driver is doing in console write function,
to avoid the hardware lockup case.

v2: incldudes the <linux/nmi.h>

Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 17:06:10 -08:00
Steven Miao
9642dbe73c serial: bfin-uart: avoid dead lock in rx irq handler in smp kernel
Disabing dma irq and lock bottom half in smp kernel doesn't ensure exclusive
uart access. Call spin_lock_irqsave() instead.

Signed-off-by: Steven Miao <realmz6@gmail.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 16:59:58 -08:00
Alan Cox
7a876b39b5 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>
2012-11-15 16:59:58 -08:00
Josh Cartwright
4bb535d2b6 serial: xilinx_uartps: kill CONFIG_OF conditional
The Zynq platform requires the use of CONFIG_OF.  Remove the #ifdef
conditionals in the uartps driver.  Make dependency explicit in Kconfig.

Signed-off-by: Josh Cartwright <josh.cartwright@ni.com>
Tested-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 16:58:19 -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
Axel Lin
1838b8c487 tty: serial: max310x: Add terminating entry for spi_device_id table
The spi_device_id table is supposed to be zero-terminated.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-14 14:49:42 -08:00
Arnd Bergmann
8a6ff8a0a2 arm: at91: mach header cleanup
This first patch serie start the cleanup of the header in mach
 by moving all the platform data to include/linux/platform_data
 
 and move the board header and drivers header next to them
 
 Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
 Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQIcBAABAgAGBQJQmQMyAAoJEOrjwV5ZMRf2N8kP/1J2DI26zhNWGIdiTPFX/HXG
 o03lvElDKDDyNtC87gU2DnYkOdjFVRpagZxv089whDs4Lt22A8ClaxEFca9K1oPg
 XO0NtuHbTL3wGlPLJH4C90bpQWY4FyIQLMfPaMeifrP1OpRkeSWAYKfFUB/wOtRC
 KWNl+WmpBt9JN9H1RIezYxpRteC+wUBKpYVZkRdT3OkQ4/oMqDIWzZqkMCTKy+Bb
 Ucs9ZFqkJ/5fSGYjHLG34VpbepFKgCqeDVugz2v+7SHvIkl0/XbRhGOdxJek54GD
 0OW8Gg5Utw47YQ1uYDR3IM00cod41/l9NYMKZm/DIEUdvNP3Mp+/X0Knehov+O+7
 7Xs8eSzBHE0mRAx2as71av08PNptNVAcJh/UAO8PWE5yLGivGrp8kQWzJItnl2ma
 8GmIK26bmMAqGuR+wANrT/pCCW5kxALE8L1JnCMzjhv5TvKE88mjUZuVmNnZGCdY
 SE/hotD2c2asZ15zv52wrGGpOALW6ZaQdlRafuDli1/yHeJ1uPOWec7NKnzytDpL
 A0r22RDyvqR7N2hunFu2aO757ojAsIWS8qfF2Yztr0UaE6rC+aoYKBwTfzvC5yhh
 gaurkH8jCUJ9EHw+GBs1pZQK9wWaK7MrlNj7/mVZ1iXErWCHZYcYNbxlx/xAFzUv
 IoHsmg6lL5By3p3nvElG
 =c5hx
 -----END PGP SIGNATURE-----

Merge tag 'for-3.8-at91_header_clean' of git://github.com/at91linux/linux-at91 into next/headers

From Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>:
arm: at91: mach header cleanup

This first patch serie start the cleanup of the header in mach
by moving all the platform data to include/linux/platform_data

and move the board header and drivers header next to them

* tag 'for-3.8-at91_header_clean' of git://github.com/at91linux/linux-at91:
  arm: at91: move at91rm9200 rtc header in drivers/rtc
  arm: at91: move reset controller header to arm/arm/mach-at91
  arm: at91: move pit define to the driver
  arm: at91: move at91_shdwc.h to arch/arm/mach-at91
  arm: at91: move board header to arch/arm/mach-at91
  arn: at91: move at91_tc.h to arch/arm/mach-at91
  arm: at91 move at91_aic.h to arch/arm/mach-at91
  arm: at91 move board.h to arch/arm/mach-at91
  arm: at91: move platfarm_data to include/linux/platform_data/atmel.h
  arm: at91: drop machine defconfig

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-11-12 22:54:08 +01:00
Linus Walleij
e59d969f44 Merge branch 'at91' into devel 2012-11-11 19:12:33 +01:00
Jean-Christophe PLAGNIOL-VILLARD
bcd2360c1f arm: at91: move platfarm_data to include/linux/platform_data/atmel.h
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
2012-11-06 20:29:33 +08:00
Russell King
3af08bd7ad SERIAL: omap: fix hardware assisted flow control
When the UART device has hardware flow control enabled, it ignores the
MCR RTS bit in the MCR register, and keeps RTS asserted as long as we
continue to read characters from the UART receiver FIFO.  This means
that when the TTY buffers become full, the UART doesn't tell the remote
end to stop sending, which causes the TTY layer to start dropping
characters.

A similar problem exists with software flow control.  We need the FIFO
register to fill when software flow control is enabled to provoke the
UART to send the XOFF character.

Fix this by implementing the throttle/unthrottle callbacks, and use
these to disable receiver interrupts.  This in turn means that the UART
FIFO will fill, which will then cause the UART's hardware to deassert
the RTS signal and/or send the XOFF character, stopping the remote end.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 12:30:28 +00:00
Russell King
2405464083 SERIAL: omap: simplify (2)
Simplify:
	- set ECB
	...
	- LCR mode A
	- clear TCRTLR
	- LCR mode B
	- clear ECB
	- set ECB and update other bits
	- LCR mode A
	- update XONANY

to:
	- set ECB
	...
	- LCR mode B
	- set ECB and update other bits
	- LCR mode A
	- update XONANY and clear TCRTLR

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 12:29:35 +00:00
Russell King
c533e51b22 SERIAL: omap: move xon/xoff setting earlier
Take advantage of the switch to mode B for accessing the TCR register,
and move the xon/xoff configuration there.  This allows further
simplication of this sequence.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 12:29:34 +00:00
Russell King
c7d059cae3 SERIAL: omap: always set TCR
We always setup the TCR register in the software flow control path,
and when hardware flow control is enabled.  Remove this redundant
setup, and place it before we setup any hardware flow control.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 12:29:33 +00:00
Russell King
18f360f865 SERIAL: omap: simplify
We have the sequence:
	- LCR mode B
	- write EFR with ECB clear
	- LCR mode normal
	- if s/w flow
		- LCR mode B
		- write EFR with ECB clear
		...
		- LCR mode B
		- write EFR with ECB clear
		- LCR mode normal

This can be simplified to:
	- if s/w flow
		- LCR mode B
		- write EFR with ECB clear
		...
	- LCR mode B
	- write EFR with ECB clear
	- LCR mode normal

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 12:29:33 +00:00
Russell King
1fe8aa8803 SERIAL: omap: don't read back LCR/MCR/EFR
There's really no reason to read back these registers while setting
the termios modes, provided we keep our cached copies up to date.
Remove these readbacks.

This has the benefit that we know that the EFR_ECB and MCR_TCRTLR
bits will always be clear, so we don't need to keep masking these
bits throughout the code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 12:29:32 +00:00
Russell King
01d70bb37c SERIAL: omap: serial_omap_configure_xonxoff() contents into set_termios
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 12:14:22 +00:00
Russell King
820344fe3d SERIAL: omap: configure xon/xoff before setting modem control lines
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 12:14:22 +00:00
Russell King
f91b55ab72 SERIAL: omap: move driver private definitions and structures to driver
struct uart_omap_port and struct uart_omap_dma, and associated
definitions are private to the driver, so there's no point them sitting
in an include file under arch/arm.  Move them into the driver itself.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 12:14:20 +00:00
Russell King
4073a53b36 SERIAL: omap: remove 'irq_pending' bitfield
irq_pending is never used, so let's remove it.  It seems to be  result
of a bad rebase of d37c6cebcb (serial: omap: move uart_omap_port
definition to C file)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 12:14:19 +00:00
Russell King
08bd4903c2 SERIAL: omap: fix MCR TCRTLR bit handling
The MCR TCRTLR bit can only be changed when ECB is set in the EFR.
Unfortunately, several places were trying to alter this bit while ECB
was clear:

- serial_omap_configure_xonxoff() was attempting to clear the bit after
  explicitly clearing the ECB bit.
- serial_omap_set_termios() was trying the same trick after setting the
  SCR, and when trying to change the TCR register when hardware flow
  control was enabled.

Fix this by ensuring that we always have ECB set whenever the TCRTLR bit
is changed.

Moreover, we start out by reading the EFR and MCR registers, which may
have indeterminent bit settings for the ECB and TCRTLR bits.  Ensure
that these bits always start off in a known state.

In order to avoid any undesired behaviour appearing through fixing this,
we also ensure that hardware assisted flow control is disabled while new
driver specific parts are not in place.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 11:54:31 +00:00
Russell King
9363f8fa89 SERIAL: omap: fix set_mctrl() breakage
c538d20c7f (and maybe previous commits) broke set_mctrl() by making
it only capable of setting bits in the MCR register.  This prevents
software controlled flow control and modem control line manipulation
via TIOCMSET/TIOCMBIC from working correctly.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 11:26:00 +00:00
Russell King
511e74f330 SERIAL: omap: no need to re-read EFR
There's no need to re-read EFR after we've recently written it; the
register is a configuration register which doesn't change its value
without us writing to it.  The last value which was written to this
register was up->efr.

Removing this re-reading avoids the possibility that we end up with
up->efr having unintended bits set, which should only be temporarily
set when accessing the enhanced features.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 11:26:00 +00:00
Russell King
d864c03bfc SERIAL: omap: remove setting of EFR SCD bit
The SCD (special character detect) bit enables comparisons with XOFF2,
which we do not program.  As the XOFF2 character remains unprogrammed,
there's little point enabling this feature along with its associated
interrupt.  Remove this, and ensure that the SCD bit is cleared.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 11:25:58 +00:00
Russell King
da5d01f23b SERIAL: omap: allow hardware assisted IXANY mode to be disabled
Nothing was clearing the UART_MCR_XONANY bit, so once the ixany
mode gets set, there's no possibility to disable it.  Clear this
bit when IXANY mode is cleared.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 11:25:57 +00:00
Russell King
0d5b166395 SERIAL: omap: allow hardware assisted rts/cts modes to be disabled
There is nothing which clears the auto RTS/CTS bits, so once hardware
flow control gets enabled, there's no possibility to disable it.
So, clear these bits when CRTSCTS is cleared.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 11:25:57 +00:00
Russell King
9aba8d5b01 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>
2012-11-04 11:25:56 +00:00
Russell King
dba05832cb 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>
2012-11-04 11:25:55 +00:00
Russell King
2cbacafd7a 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>
2012-11-04 11:25:54 +00:00
Russell King
dec94e70e1 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>
2012-11-04 11:25:53 +00:00
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