This adds support early console for MPS2 UART which can be enabled via
earlycon=mps2,0x40004000
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NVladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver adds support to the UART controller found on ARM MPS2
platform.
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NVladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Convert the SiRF UART driver from using the vendor-specific
"sirf,uart-has-rtscts" to the generic "uart-has-rtscts" DT property, as
documented by the Generic Serial DT Bindings.

The old vendor-specific property is still recognized by the driver for
backwards compatibility, but deprecated.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Convert the Freescale MXS AUART driver from using the vendor-specific
"fsl,uart-has-rtscts" to the generic "uart-has-rtscts" DT property, as
documented by the Generic Serial DT Bindings.

The old vendor-specific property is still recognized by the driver for
backwards compatibility, but it is deprecated.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Convert the Freescale IMX UART driver from using the vendor-specific
"fsl,uart-has-rtscts" to the generic "uart-has-rtscts" DT property, as
documented by the Generic Serial DT Bindings.

The old vendor-specific property is still recognized by the driver for
backwards compatibility, but deprecated.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This function is not used outside the file, so it can be static.
Signed-off-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

DMA completed normally does not require termination; only terminate
paused rx dma stemming from rx dma flush.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Using fake IIR values to perform rx dma operations unnecessarily
conflates separate operations, stopping in-progress dma with starting
new dma.

Introduce serial8250_rx_dma_flush() to handle stopping in-progress dma
[omap8250 already has equivalent omap_8250_rx_dma_flush()].
Replace rx_dma(UART_IIR_RX_TIMEOUT) with the equivalent *_rx_dma_flush(),
and rx_dma(0) with the equivalent *_rx_dma(). Handle IIR steering
in the irq handler with handle_rx_dma() helper.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Extract the operation (restarting new rx dma) performed when error
argument is true.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 27c310c5 ("serial: 8250_dma: no need to sync RX buffer")
notes the RX DMA buffer is allocated from DMA coherent memory, and
thus does not need sync'd for each transaction. The same is true
for OMAP RX DMA.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

8250 dma support requires the dmaegine driver support terminate.
Query slave caps to determine if necessary commands/properties are
supported; disable dma if not.

Note this means dmaengine driver must support slave caps reporting
as well.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

8250 dma support requires the dmaengine driver support error-free
pause/terminate and better-than-descriptor residue granularity. Query
slave caps to determine if necessary commands/properties are supported;
disable dma if not.

Note this means dmaengine driver must support slave caps reporting
as well.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The local mcr variable is never used in the tegra_uart_set_mctrl()
function, so it should be removed.
Signed-off-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Made uartlite_be and uartlite_le constants.
Signed-off-by: NMaarten Brock <m.brock@vanmierlo.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Just in case.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

HIGH_BITS_OFFSET is only used in the serial core; remove from 8250-
specific header.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Eliminate 'loss_cntx' local variable.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If !up->dma == F, then up->dma == T and can be elided from the
(up->dma && up->dma->tx_err) sub-expression.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

dma_err is not used other than for boolean evaluation;
substitute the actual operation directly.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

On Intel Penwell and Tangier the HSU block (3 HSU ports) has a global register
set which is currently not used by the driver. On Tangier it has it's own PCI
device and thus available for enumeration. Since it's not a real HSU port we
just skip it and therefore put a comment in the code why we do so.
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is no reason to compile module on non-X86 platforms, though COMPILE_TEST
is provided for sake of what it does.

While here, set default to SERIAL_8250 that user doesn't need an explicit
option to be set and hide it from non-expert.
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The BIT() macro, that is definded in bitops.h, is used in the driver. Include
necessary header for that.

While here, reorder included headers alphabetically.
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is a special register that shows interrupt status by source. In
particular case the source can be a combination of DMA Tx, DMA Rx, and UART.

Read the register and call the handlers only for sources that request an
interrupt.

Fixes: 6ede6dcd ("serial: 8250_mid: add support for DMA engine handling from UART MMIO")
Cc: stable@vger.kernel.org
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Unlike Intel Medfield and Tangier platforms DNV uses PCI BAR0 for IO compatible
resources and BAR1 for MMIO. We need latter in a way to support DMA. Introduce
an additional field in the internal structure and pass PCI BAR based on device
ID.
Reported-by: N"Lai, Poey Seng" <poey.seng.lai@intel.com>
Fixes: 6ede6dcd ("serial: 8250_mid: add support for DMA engine handling from UART MMIO")
Cc: stable@vger.kernel.org
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Bay Trail UART port does not support DCD and DSR lines. The driver
shall report that these signals are permanently active. This patch
is for HSUART enumerated via PCI.

For ACPI, see commit dfd37668 ("serial: 8250_dw: Fix get_mctrl
behaviour"). The commit also describes the possible issue if these
signals are enabled on a port without these pins.
Signed-off-by: NWan Ahmad Zainie <wan.ahmad.zainie.wan.mohamad@intel.com>
Acked-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Exposes get_mctrl() function so that it can be overriden with platform
specific implementation.
Signed-off-by: NWan Ahmad Zainie <wan.ahmad.zainie.wan.mohamad@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In ifx_spi_complete, 'more' is not initialized. It is set only if the
status is clear and only if the header is parsed OK. If any of those
is not true, 'more' can be used uninitialized in that function later.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch fixes the broken serial log when changing the clock source
of uart device. Before disabling the original clock source, this patch
enables the new clock source to protect the clock off state for a split second.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The msm_find_best_baud() function is written with the assumption
that the port->uartclk rate is fixed to a particular rate at boot
time, but now this driver changes that clk rate at runtime when
the baud is changed.

The way the hardware works is that an input clk rate comes from
the clk controller into the uart hw block. That rate is typically
1843200 or 3686400 Hz. That rate can then be divided by an
internal divider in the hw block to achieve a particular baud on
the serial wire. msm_find_best_baud() is looking for that divider
value.

A few things are wrong with the way the code is written. First,
it assumes that the maximum baud that the uart can support if the
clk rate is fixed at boot is 460800, which would correspond to an
input clk rate of 230400 * 16 == 3686400 Hz.  Except some devices
have a boot rate of 1843200 Hz or max baud of 115200, so
achieving 230400 on those devices doesn't work at all because we
don't increase the clk rate unless max baud is 460800.

Second, we can't achieve bauds higher than 460800 that require
anything besides a divisor of 1, because we always call
msm_find_best_baud() with a fixed port->uartclk rate that will
eventually be changed after we calculate the divisor. So if we
need to get a baud of 500000, we'll just multiply that by 16 and
hope that the clk can give us 500000 * 16 == 8000000 Hz, which it
typically can't do. To really achieve 500000 baud, we need to get
an input clk rate of 24000000 Hz and then divide that by 3 inside
the uart hardware.

Finally, we return success for bauds even when we can't actually
achieve them. This means that when the user asks for 500000 baud,
we actually get 921600 right now, but the user doesn't know that.

Fix all of this by searching through the divisor and clk rate
space with a combination of clk_round_rate() and baud
calculations, keeping track of the best clk rate and divisor we
find if we can't get an exact match. Typically we can get an
exact match with a divisor of 1, but sometimes we need to keep
track and try more frequencies. On my msm8916 device, this
results in all standard bauds in baud_table being supported
except for 1800, 576000, 1152000, and 4000000.

Fixes: 850b37a7 ("tty: serial: msm: Remove 115.2 Kbps maximum baud rate limitation")
Cc: "Ivan T. Ivanov" <iivanov.xz@gmail.com>
Cc: Matthew McClintock <mmcclint@codeaurora.org>
Signed-off-by: NStephen Boyd <stephen.boyd@linaro.org>
Tested-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: NAndy Gross <andy.gross@linaro.org>
Acked-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Tested-by: NCristian Prundeanu <cprundea@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Enable reporting of DSR events (which is named DTR in the registers
because Freescale uses the names as seem from a DCE).
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

According to tty_ioctl(4) (from man-pages 4.04) the rng member only
counts 0->1 transitions. For the other signals (DSR, CD, CTS) both edges
are supposed to be counted.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Make sure that events that are not handled in the irq function don't
trigger an interrupt.

When the serial port is operated in DTE mode, the events for DCD and RI
events are enabled after a system reset by default.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This gives the irq core a chance to disable the serial interrupt in case
an event isn't cleared in the handler.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When in DTE mode, the bit USR2_RIIN is active low. So invert the logic
accordingly.

Fixes: 90ebc483 ("serial: imx: repair and complete handshaking")
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Alphascale ASM9260 uart IP has some common registers with
Freescale STMP37XX. This patch provide changes which
allow to reuse mxs-auart.c code for ASM9260.
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NOleksij Rempel <linux@rempel-privat.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SC16is7xx has feature for auto hardware flow control using RTS/CTS,
so we don't need "uart_handle_cts_change" to invoke "start_tx/stop_tx"
for flow control.

In addition, for software CTS, interrupt "SC16IS7XX_IIR_CTSRTS_SRC"
just report the nCTS change of state from active(low) to inactive(high),
driver don't know when the state of nCTS change from incactive to active,
so can't resume the transmission when a peer device is again ready and
re-assert nRTS signal.
Signed-off-by: NWills Wang <wills.wang@live.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some RS-232 to RS-485 transceivers require Rx to be disabled on Tx to
avoid echo of Tx data into the Rx buffer. Specifically, the XR3160E
RS-232/RS-485/RS-422 transceiver behaves this way.

This commit disables Rx on active Tx when SER_RS485_ENABLED is active and
SER_RS485_RX_DURING_TX is disabled.

Note that this is a change in behavior of the driver. Until now
SER_RS485_RX_DURING_TX was enabled unconditionally even when disabled in
the TIOCSRS485 ioctl serial_rs485 flags field.

Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>