The mxs_auart_probe() gets the device by the get_device().
So we should put the device in the error path to balance the
device's reference counter.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We call the get_device() in the mxs_auart_probe().
For the balance of the reference count, we should put the
device in the mxs_auart_remove().
Signed-off-by: NHuang Shijie <shijie8@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

After set the AUART_CTRL0_CLKGATE, the UART will gate all the clocks off.
So the following line will not take effect.
       ................................................................
 	writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN,
 			u->membase + AUART_INTR_CLR);
       ................................................................

To fix this issue, the patch moves this gate-off line to
the end of setting registers.
Signed-off-by: NHuang Shijie <shijie8@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In most of the time, the driver needs to check if the cts flow control
is enabled. But now, the driver checks the ASYNC_CTS_FLOW flag manually,
which is not a grace way. So add a new wraper function to make the code
tidy and clean.
Signed-off-by: NHuang Shijie <shijie8@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Without checking if the auart supports the hardware flow control or not,
the old mxs_auart_set_mctrl() asserted the RTS pin blindly.

This will causes the auart receives wrong data in the following case:
   The far-end has already started the write operation, and wait for
the auart asserts the RTS pin. Then the auart starts the read operation,
but mxs_auart_set_mctrl() may be called before we set the RTSCTS in the
mxs_auart_settermios(). So the RTS pin is asserted in a wrong situation,
and we get the wrong data in the end.

This bug has been catched when I connect the mx23(DTE) to the mx53(DCE).

This patch also replaces the AUART_CTRL2_RTS with AUART_CTRL2_RTSEN.
We should use the real the hardware flow control, not the software-controled
hardware flow control.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Allow device tree probing.

Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: <linux-serial@vger.kernel.org>
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NSubodh Nijsure <snijsure@grid-net.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

Cc: linux-serial@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

This patch fixes a problem reported here:
http://article.gmane.org/gmane.linux.ports.arm.kernel/155242/match=auartSigned-off-by: NLothar Waßmann <LW@KARO-electronics.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The patch converts mxs-auart driver to clk_prepare/clk_unprepare by
using helper functions clk_prepare_enable/clk_disable_unprepare.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Alan Cox <alan@linux.intel.com>

There is no need to call uart_write_wakeup after each character send.
Once at the end of the write sequence is enough.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Do not include linux/device.h twice in drivers/tty/serial/mxs-auart.c .
Once is enough.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>