Commit Graph

97 Commits

Author SHA1 Message Date
Alexey Pelykh
1776fd059c OMAP/serial: Fix incorrect Rx FIFO threshold setting, LSR validation on Tx, and Tx FIFO IRQ generation
Original configuration of Rx FIFO threshold contained an error
that resulted Rx threshold to be effectively set to 1 character
instead of 16 characters, as noted in comments.
Checking LSR to contain UART_LSR_THRE bit set caused issue when
not all UART_IER_THRI interrupts have been properly handled.
This caused gap in Tx data, visible on high baud rates using
oscilloscope.
Setting OMAP_UART_SCR_TX_EMPTY bit in SCR caused UART_IER_THRI
interrupt to be raised only when Tx FIFO and Tx shift registers
are empty.

Signed-off-by: Alexey Pelykh <alexey.pelykh@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-05 11:13:16 -08:00
Alexey Pelykh
5fe2123647 OMAP/serial: Support 1Mbaud and similar baudrates that require Mode16 instead of Mode13
Original table in OMAP TRM named "UART Mode Baud Rates, Divisor
Values, and Error Rates" determines modes not for all common baud
rates. E.g. for 1000000 baud rate mode should be 16x, but according to
that table it's determined as 13x. According to current implementation
of mode divisor selection, after requesting 1000000 baudrate from
driver, later one will configure chip to use MODE13 divisor. Assuming
48Mhz as common UART clock speed, MODE13 divisor will effectively give
1230769 baudrate, what is quite far from desired 1000000 baudrate.
While with MODE16 divisor, chip will produce exact 1000000 baudrate.
In old driver that served UART devices (8250.c and serial_core.c) this
divisor could have been configured by user-space program, but in
omap_serial.c driver implementation this ability was not implemented
(afaik, by design) thus disallowing proper usage of MODE16-compatible
baudrates.

Signed-off-by: Alexey Pelykh <alexey.pelykh@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-17 17:20:09 -08:00
Jiri Slaby
2e124b4a39 TTY: switch tty_flip_buffer_push
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.

Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.

IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.

Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 22:30:15 -08:00
Enric Balletbo i Serra
fdbc7353e4 serial: omap: add the functionality of a 9-bit UART with userspaces CMSPAR
Some systems require the additional communication functionality of a
9-bit UART. For that we could use the "stick" (mark/space) parity
bit supported on omap serial device. When is set, if PARODD is set the
parity bit is always 1; if PARODD is not set, then the parity bit is
always 0.

Signed-off-by: Enric Balletbo i Serra <eballetbo@iseebcn.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 21:52:23 -08:00
Tony Lindgren
d9ba573718 ARM: OMAP: Move plat/omap-serial.h to include/linux/platform_data/serial-omap.h
We need to move this file to allow ARM multiplatform configurations
to build for omap2+. This can now be done as this file now only
contains platform_data.

cc: Russell King <linux@arm.linux.org.uk>
cc: Alan Cox <alan@linux.intel.com>
cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cc: Govindraj.R <govindraj.raja@ti.com>
cc: Kevin Hilman <khilman@ti.com>
cc: linux-serial@vger.kernel.org
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-12-14 14:50:09 -08:00
Linus Torvalds
d07e43d70e Merge branch 'omap-serial' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM OMAP serial updates from Russell King:
 "This series is a major reworking of the OMAP serial driver code fixing
  various bugs in the hardware-assisted flow control, extending up into
  serial_core for a couple of issues.  These fixes have been done as a
  set of progressive changes and transformations in the hope that no new
  bugs will be introduced by this series.

  The problems are many-fold, from the driver not being informed about
  updated settings, to the driver not knowing what the intentions of the
  upper layers are.

  The first four patches tackle the serial_core layer, allowing it to
  provide the necessary information to drivers, and the remaining
  patches allow the OMAP serial driver to take advantage of this.

  This brings hardware assisted RTS/CTS and XON/OFF flow control into a
  useful state.

  These patches have been in linux-next for most of the last cycle;
  indeed they predate the previous merge window.  They've also been
  posted to the OMAP people."

* 'omap-serial' of git://git.linaro.org/people/rmk/linux-arm: (21 commits)
  SERIAL: omap: fix hardware assisted flow control
  SERIAL: omap: simplify (2)
  SERIAL: omap: move xon/xoff setting earlier
  SERIAL: omap: always set TCR
  SERIAL: omap: simplify
  SERIAL: omap: don't read back LCR/MCR/EFR
  SERIAL: omap: serial_omap_configure_xonxoff() contents into set_termios
  SERIAL: omap: configure xon/xoff before setting modem control lines
  SERIAL: omap: remove OMAP_UART_SYSC_RESET and OMAP_UART_FIFO_CLR
  SERIAL: omap: move driver private definitions and structures to driver
  SERIAL: omap: remove 'irq_pending' bitfield
  SERIAL: omap: fix MCR TCRTLR bit handling
  SERIAL: omap: fix set_mctrl() breakage
  SERIAL: omap: no need to re-read EFR
  SERIAL: omap: remove setting of EFR SCD bit
  SERIAL: omap: allow hardware assisted IXANY mode to be disabled
  SERIAL: omap: allow hardware assisted rts/cts modes to be disabled
  SERIAL: core: add throttle/unthrottle callbacks for hardware assisted flow control
  SERIAL: core: add hardware assisted h/w flow control support
  SERIAL: core: add hardware assisted s/w flow control support
  ...

Conflicts:
	drivers/tty/serial/omap-serial.c
2012-12-12 07:45:16 -08:00
Bill Pemberton
ae8d8a1467 tty: remove use of __devexit
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Cc: Lucas Tavares <lucaskt@linux.vnet.ibm.com>
Cc: Daniel Walker <dwalker@fifo99.com>
Cc: Bryan Huntsman <bryanh@codeaurora.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Tony Prisk <linux@prisktech.co.nz>
Acked-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-21 15:27:46 -08:00
Bill Pemberton
9671f09921 tty: remove use of __devinit
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Lucas Tavares <lucaskt@linux.vnet.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Tony Prisk <linux@prisktech.co.nz>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-21 15:22:52 -08:00
Bill Pemberton
2d47b71602 tty: serial: remove use of __devexit_p
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Lucas Tavares <lucaskt@linux.vnet.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Tony Prisk <linux@prisktech.co.nz>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-21 15:19:52 -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
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
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
Linus Torvalds
033d9959ed Merge branch 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue changes from Tejun Heo:
 "This is workqueue updates for v3.7-rc1.  A lot of activities this
  round including considerable API and behavior cleanups.

   * delayed_work combines a timer and a work item.  The handling of the
     timer part has always been a bit clunky leading to confusing
     cancelation API with weird corner-case behaviors.  delayed_work is
     updated to use new IRQ safe timer and cancelation now works as
     expected.

   * Another deficiency of delayed_work was lack of the counterpart of
     mod_timer() which led to cancel+queue combinations or open-coded
     timer+work usages.  mod_delayed_work[_on]() are added.

     These two delayed_work changes make delayed_work provide interface
     and behave like timer which is executed with process context.

   * A work item could be executed concurrently on multiple CPUs, which
     is rather unintuitive and made flush_work() behavior confusing and
     half-broken under certain circumstances.  This problem doesn't
     exist for non-reentrant workqueues.  While non-reentrancy check
     isn't free, the overhead is incurred only when a work item bounces
     across different CPUs and even in simulated pathological scenario
     the overhead isn't too high.

     All workqueues are made non-reentrant.  This removes the
     distinction between flush_[delayed_]work() and
     flush_[delayed_]_work_sync().  The former is now as strong as the
     latter and the specified work item is guaranteed to have finished
     execution of any previous queueing on return.

   * In addition to the various bug fixes, Lai redid and simplified CPU
     hotplug handling significantly.

   * Joonsoo introduced system_highpri_wq and used it during CPU
     hotplug.

  There are two merge commits - one to pull in IRQ safe timer from
  tip/timers/core and the other to pull in CPU hotplug fixes from
  wq/for-3.6-fixes as Lai's hotplug restructuring depended on them."

Fixed a number of trivial conflicts, but the more interesting conflicts
were silent ones where the deprecated interfaces had been used by new
code in the merge window, and thus didn't cause any real data conflicts.

Tejun pointed out a few of them, I fixed a couple more.

* 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (46 commits)
  workqueue: remove spurious WARN_ON_ONCE(in_irq()) from try_to_grab_pending()
  workqueue: use cwq_set_max_active() helper for workqueue_set_max_active()
  workqueue: introduce cwq_set_max_active() helper for thaw_workqueues()
  workqueue: remove @delayed from cwq_dec_nr_in_flight()
  workqueue: fix possible stall on try_to_grab_pending() of a delayed work item
  workqueue: use hotcpu_notifier() for workqueue_cpu_down_callback()
  workqueue: use __cpuinit instead of __devinit for cpu callbacks
  workqueue: rename manager_mutex to assoc_mutex
  workqueue: WORKER_REBIND is no longer necessary for idle rebinding
  workqueue: WORKER_REBIND is no longer necessary for busy rebinding
  workqueue: reimplement idle worker rebinding
  workqueue: deprecate __cancel_delayed_work()
  workqueue: reimplement cancel_delayed_work() using try_to_grab_pending()
  workqueue: use mod_delayed_work() instead of __cancel + queue
  workqueue: use irqsafe timer for delayed_work
  workqueue: clean up delayed_work initializers and add missing one
  workqueue: make deferrable delayed_work initializer names consistent
  workqueue: cosmetic whitespace updates for macro definitions
  workqueue: deprecate system_nrt[_freezable]_wq
  workqueue: deprecate flush[_delayed]_work_sync()
  ...
2012-10-02 09:54:49 -07:00
Shubhrajyoti D
9a12fcf8b1 serial: omap: fix the reciever line error case
This patch does the following
- In case of errors if there least one data character in the RX FIFO
read it otherwise it may stall the receiver.

This is recommended in the interrupt reset method in the table 23-246 of
the omap4 TRM.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26 13:33:37 -07:00
Sourav Poddar
ac57e7f38e serial: omap: Remove unnecessary checks from suspend/resume
Drop the check for "up" being valid on suspend/resume callbacks.
It should be valid always. Get rid of the "pdata" check also as
serial_omap_get_context_loss_count() checks for it.

Tested on omap4 panda and 3630 based Beagle board.

Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-21 09:57:41 -07:00
Tony Lindgren
3dbc5ce2bf serial: omap: Request pins using pinctrl framework
Request pins using pinctrl framework. Only show a warning
on error as some boards set the pins in the bootloader
even if CONFIG_PINCTRL is enabled.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10 16:31:09 -07:00
Felipe Balbi
ce2f08ded2 serial: omap: fix DeviceTree boot
OMAP Architecture code, passes a few function
pointers for UART driver to use in order to
properly implement Power Management and Wakeup
capabilities.

The problem is that those function pointers,
which are passed (ab)using platform_data on
non-DT kernels, can't be passed down to drivers
through DT.

commit e5b57c0 (serial: omap: define helpers
for pdata function pointers) failed to take DT
kernels into consideration and caused a regression
to DT kernel boot.

Fix that by (re-)adding a check for valid pdata
pointer together with valid pdata->$FUNCTION
pointer.

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10 16:31:09 -07:00
Felipe Balbi
e36851d0fa serial: omap: fix compile breakage
when rebasing patches on top of Greg's tty-next,
it looks like automerge broke a few things which
I didn't catch (for whatever reason I didn't
have OMAP Serial enabled on .config) so I ended
up breaking the build on Greg's tty-next branch.

Fix the breakage by re-adding the three missing
members on struct uart_omap_port.

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-07 08:39:39 -07:00
Felipe Balbi
6721ab7f77 serial: omap: enable RX and TX FIFO usage
enable RX FIFO for 16 characters and TX FIFO
for 16 spaces.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:02 -07:00
Felipe Balbi
d37c6cebcb serial: omap: move uart_omap_port definition to C file
nobody needs to access the uart_omap_port structure
other than omap-serial.c file. Let's move that
structure definition to the C source file in order
to prevent anyone from accessing our structure.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:02 -07:00
Felipe Balbi
d21e4005e4 serial: omap: remove unnecessary header and add a missing one
this driver doesn't use any from <plat/dmtimer.h>, so
we can remove it without any problems.

This will, however cause a problem because omap-serial.c
was relying on indirect inclusion of <linux/platform_device.h>,
let's fix the issue by including <linux/platform_device.h>
on omap-serial.c as it should be.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:02 -07:00
Vikram Pandita
957ee7270d serial: omap: fix software flow control
Software flow control register bits were not defined correctly.

Also clarify the IXON and IXOFF logic to reflect what userspace wants.

Cc: stable@vger.kernel.org
Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Vikram Pandita <vikram.pandita@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:02 -07:00
Felipe Balbi
a6b19c333c serial: omap: make sure to put() on poll_get_char
if we would reach serial_omap_get_char() while
Data Ready bit isn't set, we would return from
it without kicking our pm timer. This would mean
we would, eventually, have an unbalanced
pm_runtime_get on our device which would prevent
it from ever sleeping again.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:02 -07:00
Felipe Balbi
9727faf470 serial: omap: implement set_wake
This has been missing from OMAP UART driver
for quite a while and it's simple enough
to implement it.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:02 -07:00
Ruchika Kharwar
0324a82102 serial: omap: unlock the port lock
This patch unlocks the port lock before calling a serial_core API
and re-acquires the port lock after calling it.
This patch fixes a system freeze issue seen when the serial_core
API uart_write_wakeup() eventually attempts to acquire the port lock
already acquired by omap serial interrupt handler.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Ruchika Kharwar <ruchika@ti.com>
Signed-off-by: Pavan Savoy <pavan_savoy@ti.com>
Signed-off-by: Vijay Badawadagi <bvijay@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:02 -07:00
Felipe Balbi
52c5513d59 serial: omap: drop "inline" from IRQ handler prototype
it makes no sense to mark our IRQ handler inline
since it's passed as a function pointer when
enabling the IRQ line.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:02 -07:00
Felipe Balbi
6d608ef351 serial: omap: optimization with section annotations
Two functions:
omap_serial_fill_features_erratas() and
of_get_uart_port_info() are only called from probe().
Marking them as __devinit gives us another
oportunity to free some code after .init.text
is done.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Ruchika Kharwar <ruchika@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:02 -07:00
Ruchika Kharwar
856e35bf59 serial: omap: fix sequence of pm_runtime_* calls.
pm_runtime_enable() needs to be invoked before
pm_runtime_use_autosuspend(), and
pm_runtime_set_autosuspend_delay() functions.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Ruchika Kharwar <ruchika@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:02 -07:00
Felipe Balbi
6c3a30c7fb serial: omap: don't save IRQ flags on hardirq
When we're running our hardirq handler, there's
not need to disable IRQs with spin_lock_irqsave()
because IRQs are already disabled. It also makes
no difference if we save or not IRQ flags.

Switch over to simple spin_lock/spin_unlock and
drop the "flags" variable.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:01 -07:00
Felipe Balbi
7e9c8e7dbf serial: omap: make sure to suspend device before remove
before removing the driver, let's make sure
to force device into a suspended state in order
to conserve power.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:01 -07:00
Felipe Balbi
1b42c8b29b serial: omap: drop unnecessary check from remove
if platform_get_drvdata() returns NULL, that's
quite a nasty bug on the driver which we want to
catch ASAP. Otherwise, that check is hugely
unneeded.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:01 -07:00
Felipe Balbi
93220dcc30 serial: omap: set dev->drvdata before enabling pm_runtime
by the time we call our first pm_runtme_get_sync()
after enable pm_runtime, our resume method might
be called. To avoid problems, we must make sure
that our dev->drvdata is set correctly before
our resume method gets called.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-06 09:17:01 -07:00