Maxburst was not set when doing the dma slave configuration. This value
is checked by the recently introduced xdmac. It causes an error when
doing the slave configuration and so prevents from using dma.
Signed-off-by: NLudovic Desroches <ludovic.desroches@atmel.com>
Cc: <stable@vger.kernel.org> # 3.12 and later
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Do not probe all serial drivers by of_serial.c which are using
device_type = "serial"; property. Only drivers which have valid
compatible strings listed in the driver should be probed.

When PORT_UNKNOWN is setup probe will fail anyway.

Arnd quotation about driver historical background:
"when I wrote that driver initially, the idea was that it would
get used as a stub to hook up all other serial drivers but after
that, the common code learned to create platform devices from DT"

This patch fix the problem with on the system with xilinx_uartps and
16550a where of_serial failed to register for xilinx_uartps and because
of irq_dispose_mapping() removed irq_desc. Then when xilinx_uartps was asking
for irq with request_irq() EINVAL is returned.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
CC: <stable@vger.kernel.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

For systems with CONFIG_SERIAL_OF_PLATFORM=y and device_type =
"serial"; property in DT of_serial.c driver maps and unmaps IRQ (because
driver probe fails). Then a driver is called but irq mapping is not
created that's why driver is failing again in again on request_irq().
Based on this use platform_get_irq() instead of platform_get_resource()
which is doing irq_desc allocation and driver itself can request IRQ.

Fix both xilinx serial drivers in the tree.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
CC: <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix uart_console_write() kernel-doc build warnings.

Warning(drivers/tty/serial/serial_core.c:1778): No description found for parameter 'putchar'
Warning(drivers/tty/serial/serial_core.c:1778): Excess function parameter 'write' description in 'uart_console_write'

Fixes: 1cfe42b7 ("serial: core: Fix kernel doc for uart_console_write()")
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This is needed by Bluetooth hci_uart module to be able to change speed
of Bluetooth controller and local UART.
Signed-off-by: NFrederic Danis <frederic.danis@linux.intel.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If the device node has a "big-endian" property and 32-bit registers, tell
the serial driver to use UPIO_MEM32BE instead of UPIO_MEM32.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NRob Herring <robh@kernel.org>

Add cases for UPIO_MEM32BE wherever there are currently cases handling
UPIO_MEM32.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NRob Herring <robh@kernel.org>

The result of netdev_priv is already implicitly cast to the type of the
left side of the assignment.

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

// <smpl>
@@
type T;
T *x;
@@

x =
- (T *)
  netdev_priv(...)
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Hardware is capable of inverting RTS signal when working
in RS-485 mode.  Expose this functionality to user space.
Relay on a matching combination of standard flags
(SER_RS485_RTS_ON_SEND and SER_RS485_RTS_AFTER_SEND) to
detect when user space is requesting inverted RTS mode.
Signed-off-by: NJakub Kicinski <kubakici@wp.pl>
Signed-off-by: NJon Ringle <jringle@gridpoint.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Serial ports of F81504/F81508/F81512 will failed when wakeup from S3(STR).

It's due to when the system wakeup from S3(STR), this PCI device's
configuration space from 0x40 to 0x40 + max_port * 0x08 should be
re-configured.

We move all initialization from pci_fintek_setup() to pci_fintek_init() and
set it to pci_serial_quirks .init section. It's will re-init this device when
system wakeup from pciserial_resume_ports().
Signed-off-by: NPeter Hung <hpeter+linux_kernel@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Document the expected behavior of kernel command lines of the forms:
    console=uart[8250],io|mmio|mmio32,<addr>[,options]
    console=uart[8250],<addr>[,options]
and
    earlycon=uart[8250],io|mmio|mmio32,<addr>[,options]
    earlycon=uart[8250],<addr>[,options]
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Restore undocumented behavior of kernel command line parameters of
the forms:
    console=uart[8250],io|mmio|mmio32,<addr>[,options]
    console=uart[8250],<addr>[,options]
where 'options' have not been specified; in this case, the hardware
is assumed to be initialized.

Fixes: c7cef0a8 ("console: Add extensible console matching")
Reported-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Implement KGDB IO operations for MIPS Fast Debug Channel (FDC). This can
be enabled via Kconfig, which also allows the channel number to be
chosen.

The magic sysrq hack is implemented in the TTY driver, detecting just ^C
for the KGDB channel, and ^O followed by a letter for the FDC console
channel.

The KGDB operations are reasonably efficient thanks to the flush
callback, with a 4 byte buffer being used in both directions to allow up
to 4 bytes to be encoded per FDC word. Reading of data for KGDB will
discard any data received on other channels, which clearly isn't ideal,
but given that there is a single FIFO shared between channels we can't
do much better.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: linux-mips@linux-mips.org
Cc: kgdb-bugreport@lists.sourceforge.net
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9147/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Add support for early console of MIPS Fast Debug Channel (FDC) on
channel 1 with a call very early from the MIPS setup_arch().
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9145/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Add TTY driver and consoles for the MIPS EJTAG Fast Debug Channel (FDC),
which is found on the per-CPU MIPS Common Device Mapped Memory (CDMM)
bus.

The FDC is a per-CPU device which is used to communicate with an EJTAG
probe. RX and TX FIFOs exist, containing 32-bits of data and 4-bit
channel numbers. 16 general data streams are implemented on this for TTY
and console use by encoding up to 4 bytes on each 32-bit FDC word.

The TTY devices are named e.g. /dev/ttyFDC3c2 for channel 2 of the FDC
attached to logical CPU 3.

These can be used for getting the kernel log, a login prompt, or as a
GDB remote transport, all over EJTAG and without needing a serial port.

It can have an interrupt to notify of when incoming data is available in
the RX FIFO or when the TX FIFO is no longer full. The detection of this
interrupt occurs in architecture / platform code, but it may be shared
with the timer and/or performance counter interrupt.

Due to the per-CPU nature of the hardware, all outgoing TTY data is
written out from a kthread which is pinned to the appropriate CPU.

The console is not bound to a specific CPU, so output will appear on the
chosen channel on whichever CPU the code is executing on. Enable with
e.g. console=fdc1 in kernel arguments. /dev/console is bound to the same
channel on the boot CPU's FDC if it exists.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9146/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

When the receiver was enabled during startup, a character could
have been in the FIFO when the UART get initially used. The
driver configures the (receive) watermark level, and flushes the
FIFO. However, the receive flag (RDRF) could still be set at that
stage (as mentioned in the register description of UARTx_RWFIFO).
This leads to an interrupt which won't be handled properly in
interrupt mode: The receive interrupt function lpuart_rxint checks
the FIFO count, which is 0 at that point (due to the flush
during initialization). The problem does not manifest when using
DMA to receive characters.

Fix this situation by explicitly read the status register, which
leads to clearing of the RDRF flag. Due to the flush just after
the status flag read, a explicit data read is not to required.
Signed-off-by: NStefan Agner <stefan@agner.ch>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Specify transmit FIFO size which might be different depending on
LPUART instance. This makes sure uart_wait_until_sent in serial
core getting called, which in turn waits and checks if the FIFO
is really empty on shutdown by using the tx_empty callback.
Without the call of this callback, the last several characters
might not yet be transmitted when closing the serial port. This
can be reproduced by simply using echo and redirect the output to
a ttyLP device.
Signed-off-by: NStefan Agner <stefan@agner.ch>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Exynos serial ports operate either in a DMA-based or interrupt-based
modes. In DMA-based mode, the UART generates a transfer data request
and a Transmission (Tx) interrupt in interrupt-based mode.

The Tx IRQ is only unmasked in interrupt-based mode and it was done
in s3c24xx_serial_start_tx(). Commit ba019a3e ("serial: samsung:
remove redundant interrupt enabling") removed the IRQ enable on that
function since it is enabled when the mode is set in enable_tx_pio().

The problem is that enable_tx_pio() is only called if the port mode
has not been set before but the mode was not cleared on .shutdown().

So if the UART was shutdown and then started up again, the mode set
will remain and the Tx IRQ won't be unmasked.

This caused a hang on at least Exynos5250, Exynos5420 and Exynos5800
when the system is rebooted or powered off.

Fixes: ba019a3e ("serial: samsung: remove redundant interrupt enabling")
Signed-off-by: NJavier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We only care if anything other than the lower 3 bits of the tty has
changed, so just check that way, which makes it a bit faster, and more
obvious what is going on.  Also, document this for future developers to
understand why we did this.
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

The clock rate is requested from a property called
"clock-frequency" in both dw8250_probe_of and
dw8250_probe_acpi. Moving the requests to dw8250_probe.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Having ACPI handle does not mean the same as having ACPI
identifier. The check is in any case useless, but having it
prevents this driver from being used for example with
multifunctional PCI devices, such as the newer Intel LPSS
devices.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Intel Tangier contains 4 HSUART ports as found on Intel Edison board which are
8250 compatible. The patch adds necessary bits to the driver.

Note that the HSU port0 is currently unavailable and thus not supported.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch replaces a switch-case by a formula using rational best
approximation that does necessary calculations for intel_mid_set_termios().

Below is a list of the calculations done for all defined baud rates. Each line
in a format: 1) nominator, 2) denominator, 3) prescaler, 4) Fuart, 5) port UART
clock, 6) list of baud rates with DLAB values.

24       25       12 48000000   64000000   4000000(1)
49       50       14 49000000   56000000   3500000(1)
4        5        16 40000000   40000000   2500000(1)
16       25       16 32000000   32000000   500000(4),1000000(2),2000000(1)
24       25       16 48000000   48000000   1500000(2),3000000(1)
2304     3125     16 36864000   36864000   576000(4),1152000(2)
8192     15625    16 26214400   26214400   50(32768),200(8192)
9216     15625    16 29491200   29491200   1800(1024),57600(32),115200(16),
					230400(8),460800(4),921600(2),1843200(1)
12288    15625    16 39321600   39321600   75(32768),150(16384),300(8192),
					600(4096),1200(2048),2400(1024),4800(512),
					9600(256),19200(128),38400(64)
45056    78125    16 28835840   28835840   110(16384)
274432   390625   16 35127296   35127296   134(16384)
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch replaces a switch-case by a formula using rational best
approximation that does necessary calculations for byt_set_termios().

Below is a list of the calculations done for all defined baud rates. Each line
in a format: 1) numerator, 2) denominator, 3) prescaler, 4) Fuart, 5) port UART
clock, 6) list of baud rates with DLAB values.

4        5        16 80000000   80000000   2500000(2)
14       25       16 56000000   56000000   3500000(1)
16       25       16 64000000   64000000   500000(8),1000000(4),2000000(2),
					4000000(1)
24       25       16 96000000   96000000   1500000(4),3000000(2)
2180     3103     16 70254592   70254592   134(32768)
2304     3125     16 73728000   73728000   576000(8),1152000(4)
8192     15625    16 52428800   52428800   50(65536),200(16384)
9216     15625    16 58982400   58982400   1800(2048),57600(64),115200(32),
					230400(16),460800(8),921600(4),1843200(2)
12288    15625    16 78643200   78643200   75(65536),150(32768),300(16384),
					600(8192),1200(4096),2400(2048),
					4800(1024),9600(512),19200(256),38400(128)
9893     17154    16 57671680   57671680   110(32768)
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Two config options exist to define powerpc MPC8xx:
* CONFIG_PPC_8xx
* CONFIG_8xx
In addition, CONFIG_PPC_8xx also defines CONFIG_CPM1 as
communication co-processor

arch/powerpc/platforms/Kconfig.cputype has contained the following
comment about CONFIG_8xx item for some years:
"# this is temp to handle compat with arch=ppc"

It looks like not many places still have that old CONFIG_8xx used,
so it is likely to be a good time to get rid of it completely ?
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

"brd->nasync" amd "brd->maxports" are the same.  They hold the number of
filled out channels in the brd->channels[] array.  These tests should
be ">=" instead of ">" so that we don't read one element past the end.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NThadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

cdns_uart_console_setup() checks port->mapbase != 0, but the port may
not be initialized yet even if this condition is met [e.g., ioremap()
may have failed]. Check port->membase != NULL instead, similar to
cdns_early_console_setup().
Signed-off-by: NThomas Betker <thomas.betker@rohde-schwarz.com>
Reviewed-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Get rid of cdns_uart_readl() and cdns_uart_writel() and just call
readl() and writel() directly.

Most of the patch was created by search-and-replace (I had to convert a
few lines manually, and break some lines longer than 80 columns):
* s/cdns_uart_readl(/readl(port->membase + /g
* s/cdns_uart_writel(\([^,]*\),/writel(\1, port->membase +/g
Signed-off-by: NThomas Betker <thomas.betker@rohde-schwarz.com>
Acked-by: NSören Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

cdns_uart_get_port() sets port->iobase = 1 to "mark port in use", but
this "in use" condition is not checked anywhere else in the code. So
remove the line, keeping port->iobase = 0 (which also makes more sense).
Signed-off-by: NThomas Betker <thomas.betker@rohde-schwarz.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The code assumes that the array cdns_uart_port[] has dimension
CDNS_UART_NR_PORTS, so let us define it this way.
Signed-off-by: NThomas Betker <thomas.betker@rohde-schwarz.com>
Reviewed-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The register space size is 0x1000, and this value [not 0xfff] should be
provided to request_mem_region(), ioremap(), etc.
Signed-off-by: NThomas Betker <thomas.betker@rohde-schwarz.com>
Reviewed-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Make the 8250 driver reserve exactly the mmio region specified
in the devicetree. This prevents conflicts between UPIO_AU type
UARTs and other devices mapped closer than the default size of
0x1000 (or 0x100 for RT2880).
Signed-off-by: NMans Rullgard <mans@mansr.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds a mapsize field to struct uart_port to be used in
conjunction with mapbase. If set, it overrides whatever value
serial8250_port_size() would otherwise report.
Signed-off-by: NMans Rullgard <mans@mansr.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add ACPI identifier for UART on AMD SOC Carrizo.
Signed-off-by: NKen Xue <Ken.Xue@amd.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Acked-by: NPeter Korsgaard <peter@korsgaard.com>
Acked-by: NTimur Tabi <timur@tabi.org>
Acked-by: NPatrice Chotard <patrice.chotard@st.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The current calculation method in the case of 9600bps, rounding error occurs
has become setting that occur timeout faster than the required time. When we
use 9600bps, 32byte buffer, 10 bit (CS8) and 100 HZ, it becomes 3 jiffies
(30msec). In fact it is necessary 33msec. This updates to the calculation
that are not actually less than the value set by the rounding error.
Also, this is nothing will be calculated value when there is no load. If there
are a lot of case load, overrun error will occur immediately.
This is by the buffer size to be calculated twice the DMA buffer, and add the
change of setting a sufficient time-out value.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SCIFA and SCIFB can detect the overrun, but it does not support.
This adds overrun handling of SCIFA and SCIFB.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Although clk_disable_unprepare() is called both on .remove()
and in .probe() error path, the clock is never actually enabled.
Signed-off-by: NJakub Kicinski <kubakici@wp.pl>
Signed-off-by: NJon Ringle <jringle@gridpoint.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

EFCR register contains RS-485 configuration which should not
be changed by shutdown.  Instead of doing a write only update
the appropriate bits.
Signed-off-by: NJakub Kicinski <kubakici@wp.pl>
Signed-off-by: NJon Ringle <jringle@gridpoint.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>