This adds documentation of device tree bindings for the
UART found on ARM MPS2 platform
Acked-by: NRob Herring <robh@kernel.org>
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>

Document a set of generic properties for describing UARTs in a
device tree:
  1. The GPIO modem control properties are currently duplicated across
     hardware-specific binding documentation,
  2. The property for dedicated RTS/CTS hardware flow control lines is
     already supported by several drivers, albeit with a vendor-specific
     prefix, hence make it generic.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NRob Herring <rob@kernel.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
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>

All other UART DT binding documentation is under
Documentation/devicetree/bindings/serial/.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
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>

If ->get_char() returns a negative error code and that can mean that
"ch" is uninitialized.  The callers of this function expect NO_POLL_CHAR
on error so let's return that.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We reach this point of code after a test of 'info->port.tty->hw_stopped',
we do not need to test for 'info->port.tty' as it is obvious that
info->port.tty is not NULL now, we have already dereferenced it.
Signed-off-by: NSudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The function alloc_ctrl_packet() can fail and return NULL. Incase it
fails print an error message and exit.
Signed-off-by: NSudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Reviewed-by: NJiri Kosina <jkosina@suse.cz>
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>

Every user of default_red, default_grn, and default_blu treats them as
unsigned char. So make it really unsigned char.

And indent the initializers and module_param properly.

This saves ~ 100 bytes of data.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This means all ->con_set_palette have to have the second parameter
const too now.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some code in vc_allocate is indented by 4 spaces. It is inside a
condition. Invert the condition and move the code to the first
indentation level (using \tab). And insert some empty lines to have
logical code blocks separated.

Then, instead of freeing in an 'if' false branch, use goto-error
label as fail path.

Maybe better to look at this patch with diff -w -b.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

MAX_NR_CONSOLES and MAX_NR_USER_CONSOLES are both 63 since they were
introduced in 1.1.54. And since vc_allocate does:

if (currcons >= MAX_NR_CONSOLES)
	return -ENXIO;

if (!vc_cons[currcons].d) {
	if (currcons >= MAX_NR_USER_CONSOLES && !capable(CAP_SYS_RESOURCE))
		return -EPERM;
}

the second check is pointless. Remove both the check and the macro
MAX_NR_USER_CONSOLES.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Reported-by: NFugang Duan <fugang.duan@nxp.com>
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>

This makes the ath79 bootconsole behave the same way as the generic 8250
bootconsole.

Also waiting for TEMT (transmit buffer is empty) instead of just THRE
(transmit buffer is not full) ensures that all characters have been
transmitted before the real serial driver starts reconfiguring the serial
controller (which would sometimes result in garbage being transmitted.)
This change does not cause a visible performance loss.

In addition, this seems to fix a hang observed in certain configurations on
many AR7xxx/AR9xxx SoCs during autoconfig of the real serial driver.

A more complete follow-up patch will disable 8250 autoconfig for ath79
altogether (the serial controller is detected as a 16550A, which is not
fully compatible with the ath79 serial, and the autoconfig may lead to
undefined behavior on ath79.)

Cc: <stable@vger.kernel.org>
Signed-off-by: NMatthias Schiffer <mschiffer@universe-factory.net>
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>