The pointer tty is dereferened in line 3135, so it is not necessary to check
null again in line 3140.
Signed-off-by: NCong Ding <dinggnu@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The pointer info is dereferened in line 1009, so it is not necessary to check
null again in line 1012.
Signed-off-by: NCong Ding <dinggnu@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: NAlexey Pelykh <alexey.pelykh@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit "serial/arc-uart: split probe from probe_earlyprintk" introduced
a build time warning:

"WARNING: vmlinux.o(.data+0x5baa0): Section mismatch in reference from
the variable early_arc_platform_driver to the function
.init.text:arc_serial_probe_earlyprintk()"

While at it - fixed another incorrectly placed initdata annotation.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: fengguang.wu@intel.com
Cc: linux-serial@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The fast lookup table to set baudrate is only right when ioclk
is 150MHz. for most platforms, ioclk is 150MHz, but some boards
might set ioclk to other frequency.

so re-calc the clk_div_reg when ioclk is not 150MHz. this patch
also gets clk in probe and puts it in remove.
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This one was omitted by the "TTY: switch tty_flip_buffer_push" patch
because I did not compile-test mips driver. Now I do.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The default burst is often 1 byte which is not very optimal.
The ideal burst size when using 16550A type port would be
1/2 of fifosize, but this does not work with all Designware
implementations. Setting it to 1/4 fifosize.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There are no stubs for ACPI functions so the driver needs to
have this ifdef or it will not compile without ACPI.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove one useless wakeup, and do not use DMA with zero byte
transfers.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The tty buffer functions are converted to using tty_port
structure instead of struct tty, so we must do the same.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

With ACPI 5.0 we can use the FixedDMA Resource Descriptor to
extract the needed information for DMA support.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add support for dmaengine API. The drivers can implement the
struct uart_8250_dma member in struct uart_8250_port and
8250.c can take care of the rest.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds support for ACPI 5.0 enumerated Designware UARTs.
ACPI does not deliver information about uart clk, so
delivering it with the driver_data.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Designware UART provides optional Component Parameter
Register that lists most of the capabilities of the UART,
including FIFO size. This uses that register to set FIFO
size for the port before registering it.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: NJamie Iles <jamie@jamieiles.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Trivial cleanup. This makes it easier to add different
methods to enumerate the device, for example ACPI 5.0
enumeration.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: NJamie Iles <jamie@jamieiles.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This needs to be done in order to later access the
Designware specific registers.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: NJamie Iles <jamie@jamieiles.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Allow 8250.c to determine the port type for us. This allows
the driver take advantage of FIFO on Designware UARTs that
have it.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: NJamie Iles <jamie@jamieiles.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Modern UARTs are able to provide information about their
capabilities such as FIFO size. This allows the drivers to
deliver this information to 8250.c when they are registering
ports.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: NJamie Iles <jamie@jamieiles.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

  for extern function uart_remove_one_port:
    need check pointer whether be NULL, before the main work.
    just like what the other extern function uart_add_one_port has done.
    uart_add_one_port and uart_remove_one_port are pair

  information:
    for the callers (such as drivers/tty/serial/jsm: jsm_tty.c, jsm_driver.c)
    they realy assume that:
      they still can call uart_remove_one_port, after uart_add_one_port failed
    we (as an extern function), have to understand it (just like kfree).
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch adds support for polling work mode, i.e. system is perform
periodical check chip status when IRQ-line is not connected to CPU.
Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NQuoc-Viet Nguyen <afelion@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some __devexit markings came in from an older patch, this removes them.
Reported-by: NWu Fengguang <fengguang.wu@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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.

This is the last one: tty_schedule_flip
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

One point is to have less places where we actually need tty pointer.
The other is that low_latency is bound to buffer processing and
buffers are now in tty_port. So it makes sense to move low_latency to
tty_port too.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

tty_insert_flip_string this time.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

tty_insert_flip_char is the next one to proceed. This one is used all
over the code, so the patch is huge.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty pointer in
many call sites. Only tty_port will be needed and hence no more
tty_port_tty_get calls in those paths.

Now 4 string flipping ones are on turn:
* tty_insert_flip_string_flags
* tty_insert_flip_string_fixed_flag
* tty_prepare_flip_string
* tty_prepare_flip_string_flags
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty pointer in
many call sites. Only tty_port will be needed and hence no more
tty_port_tty_get calls in those paths.

Here we start with tty_buffer_request_room.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

* DT binding for arc-uart
* With alll the bits in place we can now use DT probing.

Note that there's a bit of kludge right now because earlyprintk portion
of driver can't use the DT infrastrcuture to get resoures/plat_data.
This requires some infrastructre changes to of_flat_ framework
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@linux.intel.com>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

* is_emulated is now 1st element, rather than last
* also tucked all platform data refs together
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This is in preparation for devicetree based probing, where earlyprintk
won't have access to DT serial aliases which the normal probe would
absolutely rely on.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

probe routine could index into port[] with -ve index. The check in
arc_uart_init_one() was too late.

This came to light when trying to port driver to CONFIG_OF, where
bydefault of-core code sets -ve platform dev id and in absence of
DT serial aliases, driver would use the -ve index.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

NVIDIA's Tegra has multiple UART controller which supports:
- APB DMA based controller fifo read/write.
- End Of Data interrupt in incoming data to know whether end
  of frame achieve or not.
- HW controlled RTS and CTS flow control to reduce SW overhead.

Add serial driver to use all above feature.
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Reviewed-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

devm_* APIs are device managed and make cleanup and exit code simpler
and easier.

Cc: Shawn Guo <shawn.guo@linaro.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Silences checkpatch warnings.

Cc: Shawn Guo <shawn.guo@linaro.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Silences the following checkpatch error:
ERROR: that open brace { should be on the previous line

Cc: Shawn Guo <shawn.guo@linaro.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Silences the following checkpatch warning:
WARNING: Use #include <linux/io.h> instead of <asm/io.h>

Cc: Shawn Guo <shawn.guo@linaro.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fixed checkpatch errors and warnings related to incorrect spacing.

Cc: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>