This adds the infrastructure to generic earlycon for earlycon setup
using DT. The actual setup is not enabled until a following commit to
add the FDT parsing.
Signed-off-by: NRob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: NGrant Likely <grant.likely@linaro.org>

Commit 9aac5887 (tty/serial: add generic serial earlycon) moved
console option parsing from 8250_early.c and converted to kstrto*
functions from simple_strtoul along the way. However, kstrto* functions
are not equivalent in that they do not allow non-convertible characters
at the end such as "115200n8". Fix this by changing back to
simple_strtoul and ignore what checkpatch.pl says.
Reported-by: NYinghai Lu <yinghai@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit d2fd6810 (tty/serial: convert 8250 to generic earlycon)
removed setup_early_serial8250_console, but there are still 2 callers
in:

arch/mips/mti-malta/malta-init.c
drivers/firmware/pcdp.c

Add back the function implemented as a wrapper to setup_earlycon.
Reported-by: NYinghai Lu <yinghai@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The sleep function was updated to put the serial port to sleep only when necessary.
This appears to resolve the errant behavior of the driver as described in
Kernel Bug 61961 – "My Exar Corp. XR17C/D152 Dual PCI UART modem does not
work with 3.8.0".
Signed-off-by: NMichael Welling <mwelling@ieee.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix by including linux/uaccess.h:

   drivers/tty/serial/sc16is7xx.c: In function 'sc16is7xx_ioctl':
>> drivers/tty/serial/sc16is7xx.c:861:3: error: implicit declaration of function 'copy_from_user' [-Werror=implicit-function-declaration]
>> drivers/tty/serial/sc16is7xx.c:867:3: error: implicit declaration of function 'copy_to_user' [-Werror=implicit-function-declaration]
Signed-off-by: NJon Ringle <jringle@gridpoint.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NJon Ringle <jringle@gridpoint.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The SC16IS7xx is a slave I2C-bus/SPI interface to a single-channel
high performance UART. The SC16IS7xx's internal register set is
backward-compatible with the widely used and widely popular 16C450.

The SC16IS7xx also provides additional advanced features such as
auto hardware and software flow control, automatic RS-485 support, and
software reset.
Signed-off-by: NJon Ringle <jringle@gridpoint.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit fcbee4d4.

It wasn't quite ready to go in yet, sorry about that.

Cc: Simon Horman <horms@verge.net.au>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add earlycon support for the arm/arm64 semihosting debug serial
interface. This allows enabling a debug console when early_params are
processed. This is based on the arm64 earlyprintk smh support and is
intended to replace it.
Signed-off-by: NRob Herring <robh@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add earlycon support for the pl011 serial port. This allows enabling
the pl011 for console when early_params are processed. This is based
on the arm64 earlyprintk support and is intended to replace it.
Signed-off-by: NRob Herring <robh@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

With the generic earlycon infrastructure in place, convert the 8250
early console to use it.
Signed-off-by: NRob Herring <robh@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This introduces generic earlycon infrastructure for serial devices
based on the 8250 earlycon. This allows for supporting earlycon option
with other serial devices. The earlycon output is enabled at the time
early_params are processed.

Only architectures that have fixmap support or have functional ioremap
when early_params are processed are supported. This is the same
restriction that the 8250 driver had.
Signed-off-by: NRob Herring <robh@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In preparation to support FIX_EARLYCON_MEM on other arches, make the
option per arch.
Signed-off-by: NRob Herring <robh@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add driver for MEN's 16z135 High Speed UART.

The 16z135 is a memory mapped UART Core on an MCB FPGA and has 1024 byte
deep FIFO buffers for the RX and TX path. It also has configurable FIFO
fill level IRQs and data copied to and from the hardware has to be
acknowledged.
Signed-off-by: NJohannes Thumshirn <johannes.thumshirn@men.de>
Reviewed-by: NAlan Cox <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Zynq's UART is Cadence IP. Make this visible in the prompt in kconfig
and additional comments in the driver.
This also renames functions and symbols, as far as possible without
breaking user space API, to reflect the Cadence origin. This is achieved
through simple search and replace:
 - s/XUARTPS/CDNS_UART/g
 - s/xuartps/cdns_uart/g
The only exceptions are PORT_XUARTPS and the driver name, which stay as is,
due to their exposure to user space. As well as the - no legacy -
compatibility string 'xlnx,xuartps'
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

A comment states, that, according to the data sheet, to enable
interrupts the disable register should be written, but the enable
register could be left untouched. And it suspsects a HW bug requiring
to write both.
Reviewing the data sheet, these statements seem wrong. Just as one would
expect. Writing to the enable/disable register enables/disables
interrupts.
Hence the misleading comment and needless write to the disable register
are removed from the enable sequence.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

A lot of read-modify-write sequences used a one-line statement which
nests a readl() within a writel(). Convert this into code sequences that
make the three steps more obvious.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Print a warning if the clock notifier rejects a clock frequency change
to facilitate debugging (see:
http://thread.gmane.org/gmane.linux.ports.arm.kernel/304329/focus=304379)
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This is all white space and comment clean up. Mostly reformatting
comments.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Register port numbers according to order in DT aliases.
If aliases are not defined, order in DT is used.
If aliases are defined, register port id based
on that.
This patch ensures proper ttyPS0/1 assignment.

[soren]: Combined integer declarations in probe(), removed warning message
if no alias is found.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

No functional changes.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix the following Sparse warnings:

drivers/tty/serial/omap-serial.c:1418:49: warning: incorrect \
	type in argument 2 (different address spaces)
drivers/tty/serial/omap-serial.c:1418:49:    expected void const \
	[noderef] <asn:1>*from
drivers/tty/serial/omap-serial.c:1418:49:    got struct serial_rs485 \
	*<noident>
drivers/tty/serial/omap-serial.c:1426:35: warning: incorrect \
	type in argument 1 (different address spaces)
drivers/tty/serial/omap-serial.c:1426:35:    expected void [noderef] \
	<asn:1>*to
drivers/tty/serial/omap-serial.c:1426:35:    got struct serial_rs485 \
	*<noident>
Reported-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

it wasn't used by anything, just remove it.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

nobody passes a DTR_gpio to this driver, so
this code is not necessary.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

just using helper function to remove some duplicated
code a bit. While at that, also move allocation of
struct uart_omap_port higher in the code so that
we return much earlier in case of no memory.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

this way we can remove one pointer declaration.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

cleanup only, no functional changes.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

this will make sure gpio gets freed automatically
when this device is destroyed.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

per CodingStyle we should have those braces, no
functional changes.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 0324a821.

That commit tried to fix a deadlock problem when using
hci_ldisc, but it turns out the bug was in hci_ldsic
all along where it was calling ->write() from within
->write_wakeup() callback.

The problem is that ->write_wakeup() was called with
port lock held and ->write() tried to grab the same
port lock.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In (efe2f29e 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 (d358788f [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: NDoug Anderson <dianders@chromium.org>
Reviewed-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use del_timer_sync to ensure that the timer is stopped on all CPUs before
the driver exists.

This change was suggested by Thomas Gleixner.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
declarer name module_exit;
identifier ex;
@@

module_exit(ex);

@@
identifier r.ex;
@@

ex(...) {
  <...
- del_timer
+ del_timer_sync
    (...)
  ...>
}
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The mux driver is anomalous among all the serial drivers that can
define SUPPORT_SYSRQ because it can, with some configs, set
SUPPORT_SYSRQ when SERIAL_CORE_CONSOLE is not set.

Not only does this impose a pointless (but tiny) runtime overhead for
such configs but, more significantly, it adds needless complexity when
doing a code review to check for unexpected side effects of any
changes to the serial core.

This is (cross-)compile tested only because I do not have any PA-RISC
hardware.
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

According to the platform data for the legacy-C initialisation of sh-sci
for the r8a7779 SoC and my own testing the SCIx_SH4_SCIF_REGTYPE bit of
scscr needs to be set.
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In the same manner as 8250_pci, 8250_dw needs some
baytrail specific quirks to be used. The reference
clock needs to be adjusted before divided in order
to have the minimum error rate on the baudrate.

The specific byt set termios function is stored in
the driver_data field of the acpi device id via the
dw8250_acpi_desc structure.

Remove the uartclk field which is no longer delivered
as driver data.
Signed-off-by: NLoic Poulain <loic.poulain@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This will additionally show the specific UART device instead of the
general module name. This cames in handy so check for the interupts of
a specific device if there are several of them.
Signed-off-by: NAlexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: NThomas Pfaff <tpfaff@pcs.com>
Reviewed-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The two functions to write out to the console (one used in normal
console mode and one in polling console mode) were slightly different.
One used a barrier() in its loop and the other a cpu_relax().  The
barrier() really doesn't do anything since we're using rd_regl() to
read the port anyway.  Switch it to cpu_relax() to make things
consistent.

No known bugs / issues are fixed by this change--it just makes things
more consistent.
Signed-off-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The s3c24xx_serial_console_putchar() is _only_ ever used by
s3c24xx_serial_console_write() and is called in a loop (indirectly
through uart_console_write()).  There's no reason to call
s3c24xx_port_configured() for every iteration through the loop.  Move
it outside the loop.
Signed-off-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The two functions in the samsung serial driver used for writing
characters out to the port were inconsistent about whether they used
the passed in "port" or the global "cons_uart".  There was no reason
to use the global and the use of the global in
s3c24xx_serial_put_poll_char() caused a crash in the case where you
used the serial port for kgdboc but not for console.

Fix it so we used the passed in variable.

Note that this doesn't fix all problems with the samsung serial
driver.  Specifically:
* s3c24xx_serial_console_putchar() is still 99% identical to
  s3c24xx_serial_put_poll_char() (the function signature is different,
  but that's about it).  A future patch will make them slightly less
  identical and judging by other serial drivers we may need yet more
  differences eventually.
* The samsung serial driver still doesn't allow you to have more than
  one console port since it still uses the global cons_uart in
  s3c24xx_serial_console_write().
Signed-off-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>