The meson_uart_release_port() unmaps the register area but does not release
it. The meson_uart_request_port() calls devm_request_mem_region so the
release should call devm_release_mem_region() for that area so that anyt
subsequent use of these calls will work.

This fixes an issue where the addition of reset code before registering
the uart stops the console from working.
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>
Tested-by: NCarlo Caione <carlo@endlessm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Using relaxed IO accessors allows GCC to better optimise this code
as we eliminate the heavy memory barriers - for example, GCC can now
cache the address of a register across a read-modify-write sequence,
rather than reloading the base address, offset and access size flag.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add (incomplete) support for the ZTE UART to the AMBA PL011 driver.
This is similar to the ARM and ST variants, except it has a different
register address layout, and requires 32-bit accesses to the registers.
Use the newly introduced register tables and access size support to
cope with these differences.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add support for 32-bit register accesses to the AMBA PL011 UART.  This
is needed for ZTE UARTs, which require 32-bit accesses as opposed to
the more normal 16-bit accesses.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove the ST micro registers from the standard table.  These registers
should never be accessed in non-ST micro variants.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

As we can detect when the LCR register is split between TX and RX,
we don't need three entries in the table to deal with this.  Reduce
this down to two entries by converting the REG_ST_LCRH_* entries to
standard REG_LCRH_* and remove REG_LCRH.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add the ST variant register offset table to the driver.  Currently,
this is an identical copy of the standard version, but this will be
modified in the following changes.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add the register offset table to the vendor data, allowing vendor
differences to be described in this table.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a register lookup table, which allows the register offsets to be
adjusted on a per-port basis.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Instead of compare-and-set, just compute 'found'.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a temporary for the computed source address and substitute
where appropriate. No functional change.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge the multiple tty_copy_to_user() calls into a single copy
sequence within tty_copy_to_user().
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

As the of-serial driver is now 8250 specific, we can move the
file to a more appropriate place in teh 8250 subdirectory and
adapt the Kconfig help text and file name.

I'm leaving the CONFIG_SERIAL_OF_PLATFORM symbol unchanged
to avoid breaking user configuration files unnecessarily.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The only other user of this code was the nwp-serial driver, but that
is now gone, so we can remove a couple of #ifdef statments in this
driver.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The NWP serial driver is no longer needed, as the two users of
this hardware have migrated to a much faster generation hardware,
see https://en.wikipedia.org/wiki/QPACE2 for the replacement.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Benjamin Krill <ben@codiert.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The bfin-uart code uses real time with struct timeval. This will
cause problems on 32-bit architectures in 2038 when time_t
overflows.
Since the code just needs delta value of time, it is not
necessary to record them in real time.
This patch changes the code to use the monotonic time instead,
replaces struct timeval and do_gettimeofday() with u64 and
ktime_get_ns().
Signed-off-by: NDengChao <chao.deng@linaro.org>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If NO_DMA=y:

    ERROR: "dma_unmap_sg" [drivers/tty/serial/mxs-auart.ko] undefined!
    ERROR: "dma_map_sg" [drivers/tty/serial/mxs-auart.ko] undefined!

Add a dependency on HAS_DMA to fix this.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If NO_DMA=y:

    ERROR: "dma_unmap_sg" [drivers/tty/serial/imx.ko] undefined!
    ERROR: "dma_map_sg" [drivers/tty/serial/imx.ko] undefined!

Add a dependency on HAS_DMA to fix this.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If NO_DMA=y:

    drivers/built-in.o: In function `atmel_release_rx_dma':
    atmel_serial.c:(.text+0x2502e): undefined reference to `dma_unmap_sg'
    drivers/built-in.o: In function `atmel_release_tx_dma':
    atmel_serial.c:(.text+0x25080): undefined reference to `dma_unmap_sg'
    drivers/built-in.o: In function `atmel_tx_dma':
    atmel_serial.c:(.text+0x2517a): undefined reference to `dma_sync_sg_for_cpu'
    drivers/built-in.o: In function `atmel_release_tx_pdc':
    atmel_serial.c:(.text+0x252e6): undefined reference to `dma_unmap_single'
    drivers/built-in.o: In function `atmel_prepare_tx_pdc':
    atmel_serial.c:(.text+0x2531a): undefined reference to `dma_map_single'
    drivers/built-in.o: In function `atmel_release_rx_pdc':
    atmel_serial.c:(.text+0x25362): undefined reference to `dma_unmap_single'
    drivers/built-in.o: In function `atmel_tx_pdc':
    atmel_serial.c:(.text+0x25722): undefined reference to `dma_sync_single_for_cpu'
    drivers/built-in.o: In function `atmel_rx_from_pdc':
    atmel_serial.c:(.text+0x2601a): undefined reference to `dma_sync_single_for_cpu'
    drivers/built-in.o: In function `atmel_rx_from_dma':
    atmel_serial.c:(.text+0x261b2): undefined reference to `dma_sync_sg_for_cpu'
    atmel_serial.c:(.text+0x26264): undefined reference to `dma_sync_sg_for_cpu'
    drivers/built-in.o: In function `atmel_prepare_rx_pdc':
    atmel_serial.c:(.text+0x262de): undefined reference to `dma_unmap_single'
    atmel_serial.c:(.text+0x26308): undefined reference to `dma_map_single'

Add a dependency on HAS_DMA to fix this.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We found that our sc16is7xx on spi reported a TX fifo free space value
(TXLVL_REG) of 255 ocassionally, which is obviously wrong, with a
64 byte fifo and caused a buffer overrun and a kernel crash.

To trigger this, a large write to the tty is sufficient. The fifo fills,
TXLVL_REG reads zero, but the handle_tx function does a zero-data-length
write to the TX fifo anyways through sc16is7xx_fifo_write. The next
TXLVL_REG read then yields 255, for unknown reasons. A subsequent read
is ok.

Prevent zero-data-length writes if the TX fifo is full, because they are
pointless, and because they trigger wrong TXLVL read-outs.

Furthermore, prevent a TX buffer overrun if the peripheral reports values
larger than the buffer size and thus, don't allow the peripheral to crash
the kernel.
Signed-off-by: NFlorian Achleitner <achleitner.florian@fronius.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Perform common exit for both successful and error exit handling
in tty_set_ldisc(). Fixes unlikely possibility of failing to restart
input kworker when switching to the same line discipline (noop case).
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SERIAL_DO_RESTART is not used by these 3 drivers; remove.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

tty_write_flush() has no definition and the TTY_WRITE_FLUSH() macro
is never invoked; remove.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

A master pty should never be a controlling tty in Linux; if the
master pty is specified to ioctl(TIOCSCTTY), silently substitute the slave
pty as the controlling tty.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Where possible, use dev_dbg() instead of pr_debug()
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

WARN() does all of these things in one statement.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now that tty_debug() macro uses pr_debug(), the function name can
be printed when using dynamic debug; printing the function name within
the format string is redundant.

Remove the __func__ parameter and print specifier from the format string.
Add context to messages for when the function name is not printed by
dynamic debug, or when dynamic debug is not enabled.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Convert remaining printk() use to pr_*() when tty is unknown or
unsafe to use.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

With the refactor of 'locked' from parameter to local,
it's now obvious locked cannot be NULL. Remove entire conditional.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add tty as parameter to unset_locked_termios() and extract former
parameters, termios and locked, as locals.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Include the driver name in the tty_register_device_attr() error
message for invalid index.

Note that tty_err() cannot be used here because there is no tty;
use pr_err().
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use tty_notice() for unified message format from the tty core.
Fix each message to accurately reflect the cause of each termination.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Since not all ttys are devices (eg., SysV ptys), dev_*() printk macros
cannot be used. Define tty_*() printk macros that output in similar
format to dev_*() macros (ie., <driver> <tty>: .....).

Transform the most-trivial printk( LEVEL ...) usage to tty_*() usage.
NB: The function name has been eliminated from messages with unique
context, or prefixed to the format when given.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Similar to tty_name(), add tty_driver_name() helper to safely
dereference tty->driver->name (otherwise return empty string).
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

kmalloc() already emits a diagnostic for failed allocations; remove
tty-specific message.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Eliminate symbol name collision with new tty core function,
tty_driver_name().
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

tty_paranoia_check() is only used within drivers/tty/tty_io.c;
remove extern declaration in header and limit symbol to file scope.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Incorporate suggestions for tty core debug macro improvements
 - printk(KERN_DEBUG) => pr_debug()
 - ##args => ##__VA_ARGS__
 - remove do {} while()
 - output tty_name() first

cc: Joe Perches <joe@perches.com>
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Prepare for REG_* register accessors.  This change involves introducing
pl011_reg_to_offset() to convert REG_* to the hardware register offset,
and converting all call sites to use REG_* names.  We need to fix up
locations where we check for equivalence of register offsets as well.

Much of this change was made via these sed expressions:
s/ST_UART01[1x]\(_[^_]*\|_LCRH_[TR]X\)\>/REG_ST\1/
s/UART01[1x]_\(DR\|RSR\|ECR\|FR\|ILPR\|[IF]BRD\|LCRH\|CR\|IFLS\|IMSC\|RIS\|MIS\|ICR\|DMACR\)\>/REG_\1/g
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a helper to detect the split LCRH register found on ST variants.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>