Use the regshift member of struct uart_port to store the address stride
from platform data. This way we can save one dereference per call of
altera_uart_readl and altera_uart_writel.

This also allows us to use the driver without platform data, which is
needed for device tree support in the Nios2 port.
Acked-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Commit 6b5756f1 introduced the
possibility for pdev->id being -1 but the change was not done equally in
altera_uart_remove. This patch fixes this.
Acked-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The serial drivers are really just tty drivers, so move them to
drivers/tty/ to make things a bit neater overall.

This is part of the tty/serial driver movement proceedure as proposed by
Arnd Bergmann and approved by everyone involved a number of months ago.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl>
Cc: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Fixes sparse warning.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>

port->flags is of type upf_t, which corresponds to UPF_* flags.

ASYNC_BOOT_AUTOCONF is an unsigned integer, which happen to
be the same as UPF_BOOT_AUTOCONF.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This fixes tty name, major and minor numbers. The major number
204 is used across many platform-specific serial drivers, so we
use that.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Some controllers implement registers with a stride, to support
those we must implement the proper IO accessors.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This makes it much easier to integrate the driver with the rest of
the Linux (e.g. MFD subsystem).

The old method is still supported though.

Also, from now on, there is one platform device per port (no
changes are needed for the platform code, as no one registers
the devices anywhere in-tree yet).
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>,
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Some Altera UART implementations doesn't route the IRQ line, so we have
to work in polling mode.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Acked-by: NTobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

ERROR: code indent should use tabs where possible
#32: FILE: drivers/serial/altera_uart.c:397:
+^I         ALTERA_UART_STATUS_TRDY_MSK))$

total: 1 errors, 0 warnings, 39 lines checked

./patches/altera_uart-simplify-altera_uart_console_putc.patch has style problems, please review.  If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.

Please run checkpatch prior to sending patches


This fix got lost when someone merged "altera_uart: simplify
altera_uart_console_putc()".  Please don't lose fixes.  Please don't write
of mere patches which have trivial checkpatch errors.

Cc: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

altera_uart_remove should be in .devexit.text
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The check for the TRDY flag after writing the character is not needed.
Also do a cpu_relax() inside the loop.

Pass a struct uart_port to altera_uart_console_putc, so we do not need
to get it (and dereference pointers) for every character.

Cc: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Don't take the port spinlock in uart functions where the serial core
already takes care of locking/unlocking them.

The code would actually lock up on architectures where spinlocks are
implemented (not the case on nios2 where this driver is primarily used
for now, thus this bug didn't trigger).

Also protect calling altera_uart_rx_chars/altera_uart_tx_chars in the
interrupt handler by the port spinlock.

Thanks to Ian Abbott for pointing these issues out.

Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add an UART driver for the UART component available as a SOPC (System on
Programmable Chip) component for Altera FPGAs.
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>