Commit Graph

3819 Commits

Author SHA1 Message Date
Masahiro Yamada
2cda227bba serial: 8250_early: do not save and restore IER in write callback
The IER has already been masked in early_serial8250_setup(), there is
no reason to save and restore it every time early_serial8250_write()
is called.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
c0f160a735 vt: Deinline save_screen, save 238 bytes
This function compiles to 79 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
5ef6504e9d tty: Deinline __ldsem_down_write_nested, save 128 bytes
This function compiles to 491 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
fc0285f210 tty: Deinline __ldsem_down_read_nested, save 128 bytes
This function compiles to 479 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
eba3b47b26 serial/vt8500_serial: Deinline wait_for_xmitr, save 165 bytes
This function compiles to 141 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
0d5547ca1b serial/sunsu: Deinline wait_for_xmitr, save 165 bytes
This function compiles to 141 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
63744a6902 serial/sprd_serial: Deinline wait_for_xmitr, save 165 bytes
This function compiles to 141 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
be9ae5d9f7 serial/pxa: Deinline wait_for_xmitr, save 165 bytes
This function compiles to 141 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
2172076d23 serial/omap-serial: Deinline wait_for_xmitr, save 165 bytes
This function compiles to 141 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
fed76af0c7 serial/men_z135_uart: Deinline men_z135_reg_clr, save 176 bytes
This function compiles to 98 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: Peter Hurley <peter@hurleysoftware.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
9cdb933274 serial/m32r_sio: Deinline wait_for_xmitr, save 165 bytes
This function compiles to 141 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
9428d712d1 isicom: Deinline drop_dtr, save 112 bytes
This function compiles to 181 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
1c82363eef cyclades: Deinline cyz_is_loaded, save 240 bytes
This function compiles to 58 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
cb128f69ca tty/tty_ldisc: Deinline tty_ldisc_put, save 368 bytes
This function compiles to 72 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
f4581cab8d serial_core: Deinline uart_update_mctrl, save 304 bytes
This function compiles to 92 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
6d70f46ba0 serial/jsm: Deinline neo_parse_isr, save 688 bytes
This function compiles to 811 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
1a5b34ebeb serial/bcm63xx_uart: Deinline wait_for_xmitr, save 374 bytes
This function compiles to 141 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
810e20e705 isicom: Deinline WaitTillCardIsFree, save 1120 bytes
This function compiles to 96 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
8c6ba003ee cyclades: Deinline serial_paranoia_check, save 304 bytes
This function compiles to 52 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
f25d596fc2 cyclades: Deinline cyy_writeb, save 880 bytes
This function compiles to 35 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Denys Vlasenko
f88d86831b cyclades: Deinline cyy_readb, save 368 bytes
This function compiles to 32 bytes of machine code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Jiri Slaby <jslaby@suse.com>
CC: linux-serial@vger.kernel.org
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Masahiro Yamada
4828d5c30a serial: 8250_ingenic: allow to be independent of SERIAL_8250_CONSOLE
This UART driver should not depend on the console.  They should be
orthogonal.

Surround the earlycon code with CONFIG_SERIAL_EARLYCON conditional
and rip off "depends on SERIAL_8250_CONSOLE".

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Masahiro Yamada
fbccaca9bd serial: 8250_ingenic: delete redundant "select SERIAL_EARLYCON"
SERIAL_8250_INGENIC depends on SERIAL_8250_CONSOLE, which already
selects SERIAL_EARLYCON.

This line is redundant.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Masahiro Yamada
b8d20e06ea serial: 8250_uniphier: add earlycon support
This reuses the code of drivers/tty/serial/8250/8250_early.c except

  - Overwrite device->port.iotype and device->port.regshift for
    UPIO_MEM32 because of_setup_earlycon() has set them for UPIO_MEM.

  - Set device->baud to zero to prevent early8250_setup() from
    initializing the divisor register because port->uartclk does not
    match the frequency expected by this hardware.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Paul Gortmaker
d72d391c12 drivers/tty/serial: make 8250/8250_mtk.c explicitly non-modular
The Kconfig currently controlling compilation of this code is:

drivers/tty/serial/8250/Kconfig:config SERIAL_8250_MT6577
drivers/tty/serial/8250/Kconfig:        bool "Mediatek serial port support"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

We explicitly disallow a driver unbind, since that doesn't have a
sensible use case anyway, and it allows us to drop the ".remove"
code for non-modular drivers.

Since module_platform_driver() uses the same init level priority as
builtin_platform_driver() the init ordering remains unchanged with
this commit.

We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.

Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code.

Cc: Jiri Slaby <jslaby@suse.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mediatek@lists.infradead.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Paul Gortmaker
c39dfebc77 drivers/tty/serial: make serial/atmel_serial.c explicitly non-modular
The Kconfig currently controlling compilation of this code is:

drivers/tty/serial/Kconfig:config SERIAL_ATMEL
drivers/tty/serial/Kconfig:     bool "AT91 / AT32 on-chip serial port support"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

We explicitly disallow a driver unbind, since that doesn't have a
sensible use case anyway, and it allows us to drop the ".remove"
code for non-modular drivers.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We don't replace module.h with init.h since the file already has that.

We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.

Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Uwe Kleine-König
cc56884937 serial: imx: reorder functions and simplify a bit
Now that imx_mctrl_check is implemented below imx_get_mctrl the former
can call the latter directly instead of via sport->port.ops->get_mctrl.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Uwe Kleine-König
90ebc48386 serial: imx: repair and complete handshaking
The .get_mctrl callback should not report the status of RTS or LOOP, so
drop this. Instead implement reporting the state of CAR (aka DCD) and
RI.

For .set_mctrl implement setting the DTR line.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Uwe Kleine-König
18dfef9c7f serial: atmel: convert to irq handling provided mctrl-gpio
Tested-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
LABBE Corentin
5f8b90431f serial: imx: fix a possible NULL dereference
of_match_device could return NULL, and so cause a NULL pointer
dereference later.
Even if the probability of this case is very low, fixing it made
static analyzers happy.
Solving this with of_device_get_match_data made also code simplier.

Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Gavin Thomas Claugus
4d2ae601d8 drivers: serial: jsm: Switch "jsm" to JSM_DRIVER_NAME
This commit replaces every instance of the string "jsm"
in the driver with JSM_DRIVER_NAME, as the two are
equivalent. This should increase overall consistency.

Signed-off-by: Gavin Thomas Claugus <gclaugus@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13 19:59:48 -08:00
Peter Hurley
9ce119f318 tty: Fix GPF in flush_to_ldisc()
A line discipline which does not define a receive_buf() method can
can cause a GPF if data is ever received [1]. Oddly, this was known
to the author of n_tracesink in 2011, but never fixed.

[1] GPF report
    BUG: unable to handle kernel NULL pointer dereference at           (null)
    IP: [<          (null)>]           (null)
    PGD 3752d067 PUD 37a7b067 PMD 0
    Oops: 0010 [#1] SMP KASAN
    Modules linked in:
    CPU: 2 PID: 148 Comm: kworker/u10:2 Not tainted 4.4.0-rc2+ #51
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
    Workqueue: events_unbound flush_to_ldisc
    task: ffff88006da94440 ti: ffff88006db60000 task.ti: ffff88006db60000
    RIP: 0010:[<0000000000000000>]  [<          (null)>]           (null)
    RSP: 0018:ffff88006db67b50  EFLAGS: 00010246
    RAX: 0000000000000102 RBX: ffff88003ab32f88 RCX: 0000000000000102
    RDX: 0000000000000000 RSI: ffff88003ab330a6 RDI: ffff88003aabd388
    RBP: ffff88006db67c48 R08: ffff88003ab32f9c R09: ffff88003ab31fb0
    R10: ffff88003ab32fa8 R11: 0000000000000000 R12: dffffc0000000000
    R13: ffff88006db67c20 R14: ffffffff863df820 R15: ffff88003ab31fb8
    FS:  0000000000000000(0000) GS:ffff88006dc00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
    CR2: 0000000000000000 CR3: 0000000037938000 CR4: 00000000000006e0
    Stack:
     ffffffff829f46f1 ffff88006da94bf8 ffff88006da94bf8 0000000000000000
     ffff88003ab31fb0 ffff88003aabd438 ffff88003ab31ff8 ffff88006430fd90
     ffff88003ab32f9c ffffed0007557a87 1ffff1000db6cf78 ffff88003ab32078
    Call Trace:
     [<ffffffff8127cf91>] process_one_work+0x8f1/0x17a0 kernel/workqueue.c:2030
     [<ffffffff8127df14>] worker_thread+0xd4/0x1180 kernel/workqueue.c:2162
     [<ffffffff8128faaf>] kthread+0x1cf/0x270 drivers/block/aoe/aoecmd.c:1302
     [<ffffffff852a7c2f>] ret_from_fork+0x3f/0x70 arch/x86/entry/entry_64.S:468
    Code:  Bad RIP value.
    RIP  [<          (null)>]           (null)
     RSP <ffff88006db67b50>
    CR2: 0000000000000000
    ---[ end trace a587f8947e54d6ea ]---

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-12 23:05:28 -08:00
Geert Uytterhoeven
e1dd3bef6d serial: earlycon: Add missing spinlock initialization
If an earlycon console driver needs to acquire the uart_port.lock
spinlock for serial console output, and CONFIG_DEBUG_SPINLOCK=y:

    BUG: spinlock bad magic on CPU#0, swapper/0
     lock: sci_ports+0x0/0x3480, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
    CPU: 0 PID: 0 Comm: swapper Not tainted 4.4.0-rc2-koelsch-g62ea5edf143bb1d0-dirty #2083
    Hardware name: Generic R8A7791 (Flattened Device Tree)
    [<c00173a0>] (unwind_backtrace) from [<c0013094>] (show_stack+0x10/0x14)
    [<c0013094>] (show_stack) from [<c01f2338>] (dump_stack+0x70/0x8c)
    [<c01f2338>] (dump_stack) from [<c00702d8>] (do_raw_spin_lock+0x20/0x190)
    [<c00702d8>] (do_raw_spin_lock) from [<c0267590>] (serial_console_write+0x4c/0x130)
    [<c0267590>] (serial_console_write) from [<c00734c4>] (call_console_drivers.constprop.13+0xc8/0xec)
    [<c00734c4>] (call_console_drivers.constprop.13) from [<c0074ef0>] (console_unlock+0x354/0x440)
    [<c0074ef0>] (console_unlock) from [<c0075bb4>] (register_console+0x2a0/0x394)
    [<c0075bb4>] (register_console) from [<c06cb750>] (of_setup_earlycon+0x90/0xa4)
    [<c06cb750>] (of_setup_earlycon) from [<c06cfb60>] (setup_of_earlycon+0x118/0x13c)
    [<c06cfb60>] (setup_of_earlycon) from [<c06b34ac>] (do_early_param+0x64/0xb4)
    [<c06b34ac>] (do_early_param) from [<c00472c0>] (parse_args+0x254/0x350)
    [<c00472c0>] (parse_args) from [<c06b3860>] (parse_early_options+0x2c/0x3c)
    [<c06b3860>] (parse_early_options) from [<c06b389c>] (parse_early_param+0x2c/0x40)
    [<c06b389c>] (parse_early_param) from [<c06b5b08>] (setup_arch+0x520/0xaf0)
    [<c06b5b08>] (setup_arch) from [<c06b3948>] (start_kernel+0x94/0x370)
    [<c06b3948>] (start_kernel) from [<40008090>] (0x40008090)

Initialize the spinlock in of_setup_earlycon() and register_earlycon(),
to fix this for both DT-based and legacy earlycon.  If the driver would
reinitialize the spinlock again, this is harmless, as it's allowed to
reinitialize an unlocked spinlock.

Alternatives are:
  - Drivers having an early_serial_console_write() that only performs
    the core functionality of serial_console_write(), without acquiring
    the lock (which may be unsafe, depending on the hardware),
  - Drivers initializing the spinlock in their private earlycon setup
    functions.

As uart_port is owned by generic serial_core, and uart_port.lock is
initialized by uart_add_one_port() for the normal case, this can better
be handled in the earlycon core.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Reported-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-12 23:05:28 -08:00
Yoshihiro Shimoda
d09959e752 serial: sh-sci: Fix length of scatterlist
This patch fixes an issue that the "length" of scatterlist should be
set using sg_dma_len(). Otherwise, a dmaengine driver cannot work
correctly if CONFIG_NEED_SG_DMA_LENGTH=y.

Fixes: 7b39d90184 (serial: sh-sci: Fix NULL pointer dereference if HIGHMEM is enabled)
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-12 21:42:31 -08:00
Peter Hurley
ac8f3bf883 n_tty: Fix poll() after buffer-limited eof push read
commit 40d5e0905a ("n_tty: Fix EOF push handling") fixed EOF push
for reads. However, that approach still allows a condition mismatch
between poll() and read(), where poll() returns POLLIN but read()
blocks. This state can happen when a previous read() returned because
the user buffer was full and the next character was an EOF not at the
beginning of the line. While the next read() will properly identify
the condition and advance the read buffer tail without improperly
indicating an EOF file condition (ie., read() will not mistakenly
return 0), poll() will mistakenly indicate POLLIN.

Although a possible solution would be to peek at the input buffer
in n_tty_poll(), the better solution in this patch is to eat the
EOF during the previous read() (ie., fix the problem by eliminating
the condition).

The current canon line buffer copy limits the scan for next end-of-line
to the smaller of either,
   a. the remaining user buffer size
   b. completed lines in the input buffer
When the remaining user buffer size is exactly one less than the
end-of-line marked by EOF push, the EOF is not scanned nor skipped
but left for subsequent reads. In the example below, the scan
index 'eol' has stopped at the EOF because it is past the scan
limit of 5 (not because it has found the next set bit in read_flags)

   user buffer [*nr = 5]    _ _ _ _ _

   read_flags               0 0 0 0 0   1
   input buffer             h e l l o [EOF]
                            ^           ^
                           /           /
                         tail        eol

   result: found = 0, tail += 5, *nr += 5

Instead, allow the scan to peek ahead 1 byte (while still limiting the
scan to completed lines in the input buffer). For the example above,

   result: found = 1, tail += 6, *nr += 5

Because the scan limit is now bumped +1 byte, when the scan is
completed, the tail advance and the user buffer copy limit is
re-clamped to *nr when EOF is _not_ found.

Fixes: 40d5e0905a ("n_tty: Fix EOF push handling")
Cc: <stable@vger.kernel.org> # 3.12+
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-12 21:42:31 -08:00
Masahiro Yamada
7be047e035 serial: 8250_uniphier: fix dl_read and dl_write functions
The register offset must be shifted by regshift, otherwise the
baudrate is not set.  I missed the issue probably because the
divisor register was already set by the boot loader.

Fixes: 1a8d2903cb ("serial: 8250_uniphier: add UniPhier serial driver")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-12 21:42:31 -08:00
Stephen Boyd
23a8802466 serial: msm_serial: Make config tristate
This driver works as a module, so mark it as a tristate config
instead of a bool.

Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Andy Gross <agross@codeaurora.org>
Signed-off-by: Andy Gross <agross@codeaurora.org>
2015-12-08 13:01:01 -06:00
Arnd Bergmann
bd63acf9e9 serial: export fsl8250_handle_irq
fsl8250_handle_irq is now used by the of_serial driver, and that fails
if it is a loadable module:

ERROR: "fsl8250_handle_irq" [drivers/tty/serial/of_serial.ko] undefined!

This exports the symbol to avoid randconfig errors.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: d43b54d269 ("serial: Enable Freescale 16550 workaround on arm")
Cc: Scott Wood <scottwood@freescale.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-20 16:19:54 -08:00
Heikki Krogerus
fa70045e9d serial: 8250_mid: Add missing dependency
8250_mid uses rational_best_approximation() function, so the
driver needs to select CONFIG_RATIONAL option.

This fixes build error when CONFIG_RATIONAL is not enabled:

drivers/built-in.o: In function `mid8250_set_termios':
8250_mid.c:(.text+0x10169a): undefined reference to `rational_best_approximation'

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-20 16:19:54 -08:00
Peter Hurley
6b2a3d628a tty: audit: Fix audit source
The data to audit/record is in the 'from' buffer (ie., the input
read buffer).

Fixes: 72586c6061 ("n_tty: Fix auditing support for cannonical mode")
Cc: stable <stable@vger.kernel.org> # 4.1+
Cc: Miloslav Trmač <mitr@redhat.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Laura Abbott <labbott@fedoraproject.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-20 16:19:54 -08:00
Guenter Roeck
f356d7a7dd serial: etraxfs-uart: Fix crash
Since commit 7d8c70d804 ("serial: mctrl-gpio: rename init function"),
crisv32 either do not build or crash as follows.

Unable to handle kernel NULL pointer dereference
Linux 4.3.0-rc7-next-20151101 #1 Sun Nov 1 11:41:28 PST 2015
...
Call Trace: [<c0004a0e>] show_stack+0x0/0x9e
[<c004c0c0>] printk+0x0/0x2c
[<c00059d4>] show_registers+0x14a/0x1c2
[<c004c0c0>] printk+0x0/0x2c
[<c0004b52>] die_if_kernel+0x7c/0x9e
[<c0005346>] do_page_fault+0x32e/0x3e6
[<c01dc59c>] of_get_property+0x0/0x2c
[<c01e0558>] of_irq_parse_raw+0x12a/0x376
[<c01dc59c>] of_get_property+0x0/0x2c
[<c0053aca>] get_page_from_freelist+0x73e/0x856
[<c01dc59c>] of_get_property+0x0/0x2c
[<c0008912>] d_mmu_refill+0x10a/0x112
[<c01b488c>] devm_kmalloc+0x40/0x56
[<c01b47d0>] add_dr+0xc/0x1c
[<c01b4800>] devm_add_action+0x2/0x4e
[<c01abdbc>] mctrl_gpio_init_noauto+0x1c/0x76
[<c01abf9e>] mctrl_gpio_init+0x22/0x110

The function call in the etraxfs-uart driver was not renamed,
possibly due to interference with commit 7b9c5162c1 ("serial:
etraxfs-uart: use mctrl_gpio helpers for handling modem signals").

Fixes: 7d8c70d804 ("serial: mctrl-gpio: rename init function")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Niklas Cassel <nks@flawful.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-20 16:19:54 -08:00
Peter Hurley
bec8bf61dc serial: fsl_lpuart: Fix earlycon support
Earlycon support for Freescale lpuart should only be enabled when
console support is enabled.

Fixes: 1d59b382f1 ("serial: fsl_lpuart: add earlycon support")
Acked-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-20 16:19:54 -08:00
Simon Arlott
83f7fa6c29 bcm63xx_uart: Use the device name when registering an interrupt
Use the device name when registering an interrupt so that multiple
ports don't all have the same interrupt name.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-20 16:19:54 -08:00
Peter Hurley
17a6921971 tty: Fix direct use of tty buffer work
Recent abstraction of tty buffer work introduced api to manage
tty input kworker; use it.

Fixes: e176058f0d ("tty: Abstract tty buffer work")
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-20 16:19:54 -08:00
Peter Hurley
ee0c1a65cf tty: Fix tty_send_xchar() lock order inversion
The correct lock order is atomic_write_lock => termios_rwsem, as
established by tty_write() => n_tty_write().

Fixes: c274f6ef1c ("tty: Hold termios_rwsem for tcflow(TCIxxx)")
Reported-and-Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-20 16:19:54 -08:00
Linus Walleij
58383c7842 gpio: change member .dev to .parent
The name .dev in a struct is normally reserved for a struct device
that is let us say a superclass to the thing described by the struct.
struct gpio_chip stands out by confusingly using a struct device *dev
to point to the parent device (such as a platform_device) that
represents the hardware. As we want to give gpio_chip:s real devices,
this is not working. We need to rename this member to parent.

This was done by two coccinelle scripts, I guess it is possible to
combine them into one, but I don't know such stuff. They look like
this:

@@
struct gpio_chip *var;
@@
-var->dev
+var->parent

and:

@@
struct gpio_chip var;
@@
-var.dev
+var.parent

and:

@@
struct bgpio_chip *var;
@@
-var->gc.dev
+var->gc.parent

Plus a few instances of bgpio that I couldn't figure out how
to teach Coccinelle to rewrite.

This patch hits all over the place, but I *strongly* prefer this
solution to any piecemal approaches that just exercise patch
mechanics all over the place. It mainly hits drivers/gpio and
drivers/pinctrl which is my own backyard anyway.

Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Rafał Miłecki <zajec5@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Alek Du <alek.du@intel.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-11-19 09:24:35 +01:00
Linus Torvalds
9cf5c095b6 asm-generic cleanups
The asm-generic changes for 4.4 are mostly a series from Christoph Hellwig
 to clean up various abuses of headers in there. The patch to rename the
 io-64-nonatomic-*.h headers caused some conflicts with new users, so I
 added a workaround that we can remove in the next merge window.
 
 The only other patch is a warning fix from Marek Vasut
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Merge tag 'asm-generic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic cleanups from Arnd Bergmann:
 "The asm-generic changes for 4.4 are mostly a series from Christoph
  Hellwig to clean up various abuses of headers in there.  The patch to
  rename the io-64-nonatomic-*.h headers caused some conflicts with new
  users, so I added a workaround that we can remove in the next merge
  window.

  The only other patch is a warning fix from Marek Vasut"

* tag 'asm-generic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  asm-generic: temporarily add back asm-generic/io-64-nonatomic*.h
  asm-generic: cmpxchg: avoid warnings from macro-ized cmpxchg() implementations
  gpio-mxc: stop including <asm-generic/bug>
  n_tracesink: stop including <asm-generic/bug>
  n_tracerouter: stop including <asm-generic/bug>
  mlx5: stop including <asm-generic/kmap_types.h>
  hifn_795x: stop including <asm-generic/kmap_types.h>
  drbd: stop including <asm-generic/kmap_types.h>
  move count_zeroes.h out of asm-generic
  move io-64-nonatomic*.h out of asm-generic
2015-11-06 14:22:15 -08:00
Linus Torvalds
75f5db39ff spi: Updates for v4.4
Quite a lot of activity in SPI this cycle, almost all of it in drivers
 with a few minor improvements and tweaks in the core.
 
  - Updates to pxa2xx to support Intel Broxton and multiple chip selects.
  - Support for big endian in the bcm63xx driver.
  - Multiple slave support for the mt8173
  - New driver for the auxiliary SPI controller in bcm2835 SoCs.
  - Support for Layerscale SoCs in the Freescale DSPI driver.
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Merge tag 'spi-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi updates from Mark Brown:
 "Quite a lot of activity in SPI this cycle, almost all of it in drivers
  with a few minor improvements and tweaks in the core.

   - Updates to pxa2xx to support Intel Broxton and multiple chip selects.
   - Support for big endian in the bcm63xx driver.
   - Multiple slave support for the mt8173
   - New driver for the auxiliary SPI controller in bcm2835 SoCs.
   - Support for Layerscale SoCs in the Freescale DSPI driver"

* tag 'spi-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (87 commits)
  spi: pxa2xx: Rework self-initiated platform data creation for non-ACPI
  spi: pxa2xx: Add support for Intel Broxton
  spi: pxa2xx: Detect number of enabled Intel LPSS SPI chip select signals
  spi: pxa2xx: Add output control for multiple Intel LPSS chip selects
  spi: pxa2xx: Use LPSS prefix for defines that are Intel LPSS specific
  spi: Add DSPI support for layerscape family
  spi: ti-qspi: improve ->remove() callback
  spi/spi-xilinx: Fix race condition on last word read
  spi: Drop owner assignment from spi_drivers
  spi: Add THIS_MODULE to spi_driver in SPI core
  spi: Setup the master controller driver before setting the chipselect
  spi: dw: replace magic constant by DW_SPI_DR
  spi: mediatek: mt8173 spi multiple devices support
  spi: mediatek: handle controller_data in mtk_spi_setup
  spi: mediatek: remove mtk_spi_config
  spi: mediatek: Update document devicetree bindings to support multiple devices
  spi: fix kernel-doc warnings about missing return desc in spi.c
  spi: fix kernel-doc warnings about missing return desc in spi.h
  spi: pxa2xx: Align a few defines
  spi: pxa2xx: Save other reg_cs_ctrl bits when configuring chip select
  ...
2015-11-05 13:15:12 -08:00
Linus Torvalds
f66477a0ae The majority of the changes are driver updates and new device
support. The core framework is mostly unchanged this time
 around, with only a couple patches to expose a clk provider
 API and make getting clk parent names from DT more robust.
 
 Driver updates:
 
 - Support for clock controllers found on Broadcom Northstar
   SoCs and bcm2835 SoC
 
 - Support for Allwinner audio clocks
 
 - A few cleanup patches for Tegra drivers and support for the
   highest DFLL frequencies on Tegra124
 
 - Samsung exynos7 fixes and improvements
 
 - i.Mx SoC updates to add a few missing clocks and keep debug
   uart clocks on during kernel intialization
 
 - Some mediatek cleanups and support for more subsystem clocks
 
 - Support for msm8916 gpu/audio clocks and qcom's GDSC power domain
   controllers
 
 - A new driver for the Silabs si514 clock chip
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Merge tag 'clk-for-linus-20151104' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux

Pull clk updates from Stephen Boyd:
 "The majority of the changes are driver updates and new device support.
  The core framework is mostly unchanged this time around, with only a
  couple patches to expose a clk provider API and make getting clk
  parent names from DT more robust.

  Driver updates:

   - Support for clock controllers found on Broadcom Northstar SoCs and
     bcm2835 SoC

   - Support for Allwinner audio clocks

   - A few cleanup patches for Tegra drivers and support for the highest
     DFLL frequencies on Tegra124

   - Samsung exynos7 fixes and improvements

   - i.Mx SoC updates to add a few missing clocks and keep debug uart
     clocks on during kernel intialization

   - Some mediatek cleanups and support for more subsystem clocks

   - Support for msm8916 gpu/audio clocks and qcom's GDSC power domain
     controllers

   - A new driver for the Silabs si514 clock chip"

* tag 'clk-for-linus-20151104' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (143 commits)
  clk: qcom: msm8960: Fix dsi1/2 halt bits
  clk: lpc18xx-cgu: fix potential system hang when disabling unused clocks
  clk: lpc18xx-ccu: fix potential system hang when disabling unused clocks
  clk: Add clk_hw_is_enabled() for use by clk providers
  clk: Add stubs for of_clk_*() APIs when CONFIG_OF=n
  clk: versatile-icst: fix memory leak
  clk: Remove clk_{register,unregister}_multiplier()
  clk: iproc: define Broadcom NS2 iProc clock binding
  clk: iproc: define Broadcom NSP iProc clock binding
  clk: ns2: add clock support for Broadcom Northstar 2 SoC
  clk: iproc: Separate status and control variables
  clk: iproc: Split off dig_filter
  clk: iproc: Add PLL base write function
  clk: nsp: add clock support for Broadcom Northstar Plus SoC
  clk: iproc: Add PWRCTRL support
  clk: cygnus: Convert all macros to all caps
  ARM: cygnus: fix link failures when CONFIG_COMMON_CLK_IPROC is disabled
  clk: imx31: add missing of_node_put
  clk: imx27: add missing of_node_put
  clk: si5351: add missing of_node_put
  ...
2015-11-05 12:59:36 -08:00
Linus Torvalds
fd0d351de7 TTY/Serial driver patches for 4.4-rc1
Here is the big tty and serial driver update for 4.4-rc1.
 
 Lots of serial driver updates and a few small tty core changes.  Full
 details in the shortlog.
 
 All of these have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the big tty and serial driver update for 4.4-rc1.

  Lots of serial driver updates and a few small tty core changes.  Full
  details in the shortlog.

  All of these have been in linux-next for a while"

* tag 'tty-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (148 commits)
  tty: Use unbound workqueue for all input workers
  tty: Abstract tty buffer work
  tty: Prevent tty teardown during tty_write_message()
  tty: core: Use correct spinlock flavor in tiocspgrp()
  tty: Combine SIGTTOU/SIGTTIN handling
  serial: amba-pl011: fix incorrect integer size in pl011_fifo_to_tty()
  ttyFDC: Fix build problems due to use of module_{init,exit}
  tty: remove unneeded return statement
  serial: 8250_mid: add support for DMA engine handling from UART MMIO
  dmaengine: hsu: remove platform data
  dmaengine: hsu: introduce stubs for the exported functions
  dmaengine: hsu: make the UART driver in control of selecting this driver
  serial: fix mctrl helper functions
  serial: 8250_pci: Intel MID UART support to its own driver
  serial: fsl_lpuart: add earlycon support
  tty: disable unbind for old 74xx based serial/mpsc console port
  serial: pl011: Spelling s/clocks-names/clock-names/
  n_tty: Remove reader wakeups for TTY_BREAK/TTY_PARITY chars
  tty: synclink, fix indentation
  serial: at91, fix rs485 properties
  ...
2015-11-04 21:35:12 -08:00
Linus Torvalds
41ecf1404b xen: features for 4.4-rc0
- Improve balloon driver memory hotplug placement.
 - Use unpopulated hotplugged memory for foreign pages (if
   supported/enabled).
 - Support 64 KiB guest pages on arm64.
 - CPU hotplug support on arm/arm64.
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Merge tag 'for-linus-4.4-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from David Vrabel:

 - Improve balloon driver memory hotplug placement.

 - Use unpopulated hotplugged memory for foreign pages (if
   supported/enabled).

 - Support 64 KiB guest pages on arm64.

 - CPU hotplug support on arm/arm64.

* tag 'for-linus-4.4-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (44 commits)
  xen: fix the check of e_pfn in xen_find_pfn_range
  x86/xen: add reschedule point when mapping foreign GFNs
  xen/arm: don't try to re-register vcpu_info on cpu_hotplug.
  xen, cpu_hotplug: call device_offline instead of cpu_down
  xen/arm: Enable cpu_hotplug.c
  xenbus: Support multiple grants ring with 64KB
  xen/grant-table: Add an helper to iterate over a specific number of grants
  xen/xenbus: Rename *RING_PAGE* to *RING_GRANT*
  xen/arm: correct comment in enlighten.c
  xen/gntdev: use types from linux/types.h in userspace headers
  xen/gntalloc: use types from linux/types.h in userspace headers
  xen/balloon: Use the correct sizeof when declaring frame_list
  xen/swiotlb: Add support for 64KB page granularity
  xen/swiotlb: Pass addresses rather than frame numbers to xen_arch_need_swiotlb
  arm/xen: Add support for 64KB page granularity
  xen/privcmd: Add support for Linux 64KB page granularity
  net/xen-netback: Make it running on 64KB page granularity
  net/xen-netfront: Make it running on 64KB page granularity
  block/xen-blkback: Make it running on 64KB page granularity
  block/xen-blkfront: Make it running on 64KB page granularity
  ...
2015-11-04 17:32:42 -08:00
Linus Torvalds
14c7909290 Merge branch 'parisc-4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc updates from Helge Deller:
 "The most important change is that we reduce L1_CACHE_BYTES to 16
  bytes, for which a trivial patch for XPS in the network layer was
  needed.  Then we wire up the sys_membarrier and userfaultfd syscalls
  and added two other small cleanups"

* 'parisc-4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Change L1_CACHE_BYTES to 16
  net/xps: Fix calculation of initial number of xps queues
  parisc: reduce syslog debug output
  parisc: serial/mux: Convert to uart_console_device instead of open-coded
  parisc: Wire up userfaultfd syscall
  parisc: allocate sys_membarrier system call number
2015-11-04 11:30:22 -08:00
Mark Brown
4c84518523 Merge remote-tracking branches 'spi/topic/omap-100k', 'spi/topic/omap-uwire', 'spi/topic/owner', 'spi/topic/pxa' and 'spi/topic/pxa2xx' into spi-next 2015-11-04 11:02:12 +00:00
David S. Miller
b75ec3af27 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-11-01 00:15:30 -04:00
Andrew F. Davis
3821a065f5 spi: Drop owner assignment from spi_drivers
An spi_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-28 10:30:17 +09:00
Julien Grall
9652c08012 tty/hvc: xen: Use xen page definition
The console ring is always based on the page granularity of Xen.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23 14:20:37 +01:00
Axel Lin
aa0bdd2995 parisc: serial/mux: Convert to uart_console_device instead of open-coded
The implementation of mux_console_device() is very similar to
uart_console_device(). Setting .data field in mux_console then we can
convert to use uart_console_device().

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2015-10-22 15:44:28 +02:00
David S. Miller
26440c835f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/usb/asix_common.c
	net/ipv4/inet_connection_sock.c
	net/switchdev/switchdev.c

In the inet_connection_sock.c case the request socket hashing scheme
is completely different in net-next.

The other two conflicts were overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-20 06:08:27 -07:00
Peter Hurley
e052c6d15c tty: Use unbound workqueue for all input workers
The commonly accepted wisdom that scheduling work on the same cpu
that handled interrupt i/o benefits from cache-locality is only
true if the cpu is idle (since bound kworkers are often the highest
vruntime and thus the lowest priority).

Measurements of scheduling via the unbound queue show lowered
worst-case latency responses of up to 5x over bound workqueue, without
increase in average latency or throughput.

pty i/o test measurements show >3x (!) reduced total running time; tests
previously taking ~8s now complete in <2.5s.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:32:21 -07:00
Peter Hurley
e176058f0d tty: Abstract tty buffer work
Introduce API functions to restart and cancel tty buffer work, rather
than manipulate buffer work directly.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:32:21 -07:00
Peter Hurley
4b41b9539a tty: Prevent tty teardown during tty_write_message()
tty_write_message() allows the caller to directly write to a specific
tty. Since the line discipline is bypassed for the direct write,
nothing prevents the tty from being torn down after the tty count is
checked.

Hold the tty lock for the duration of the direct write.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:30:49 -07:00
Peter Hurley
1e86b5bf15 tty: core: Use correct spinlock flavor in tiocspgrp()
tiocspgrp() is the ioctl handler for TIOCSPGRP, which runs in
non-atomic context; use spin_lock/unlock_irq (since interrupt state
is on).

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:30:49 -07:00
Peter Hurley
2812d9e9fd tty: Combine SIGTTOU/SIGTTIN handling
The job_control() check in n_tty_read() has nearly identical purpose
and results as tty_check_change(). Both functions' purpose is to
determine if the current task's pgrp is the foreground pgrp for the tty,
and if not, to signal the current pgrp.

Introduce __tty_check_change() which takes the signal to send
and performs the shared operations for job control() and
tty_check_change().

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:30:49 -07:00
Timur Tabi
71a5cd8a4a serial: amba-pl011: fix incorrect integer size in pl011_fifo_to_tty()
The UART_DUMMY_DR_RX status bit is equal to (1 << 16), so a u16 is too small
to hold that value.  The result is that UART_DUMMY_DR_RX is never passed
to uart_insert_char().  This means that we're always accepting characters,
even when CREAD (in termios) is not set.

Signed-off-by: Timur Tabi <timur@codeaurora.org>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:29:21 -07:00
James Hogan
3e8137a185 ttyFDC: Fix build problems due to use of module_{init,exit}
Commit 0fd972a7d9 (module: relocate module_init from init.h to
module.h) broke the build of ttyFDC driver due to that driver's (mis)use
of module_mips_cdmm_driver() without first including module.h, for
example:

In file included from ./arch/mips/include/asm/cdmm.h +11 :0,
                 from drivers/tty/mips_ejtag_fdc.c +34 :
include/linux/device.h +1295 :1: warning: data definition has no type or storage class
./arch/mips/include/asm/cdmm.h +84 :2: note: in expansion of macro ‘module_driver’
drivers/tty/mips_ejtag_fdc.c +1157 :1: note: in expansion of macro ‘module_mips_cdmm_driver’
include/linux/device.h +1295 :1: error: type defaults to ‘int’ in declaration of ‘module_init’ [-Werror=implicit-int]
./arch/mips/include/asm/cdmm.h +84 :2: note: in expansion of macro ‘module_driver’
drivers/tty/mips_ejtag_fdc.c +1157 :1: note: in expansion of macro ‘module_mips_cdmm_driver’
drivers/tty/mips_ejtag_fdc.c +1157 :1: warning: parameter names (without types) in function declaration

Instead of just adding the module.h include, switch to using the new
builtin_mips_cdmm_driver() helper macro and drop the remove callback,
since it isn't needed. If module support is added later, the code can
always be resurrected.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.2.x-
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:29:21 -07:00
Guillaume Gomez
52772ea615 tty: remove unneeded return statement
Signed-off-by: Guillaume Gomez <guillaume1.gomez@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:29:21 -07:00
Frederic Danis
f967fc8f16 Revert "serial: 8250_dma: don't bother DMA with small transfers"
This reverts commit 9119fba0cf.

This commit prevents from sending "big" file using Bluetooth.
When sending a lot of data quickly through the Bluetooth interface, and
after a variable amount of data sent, transfer fails with error:
    kernel: [  415.247453] Bluetooth: hci0 hardware error 0x00

Found on T100TA.

After reverting this commit, send works fine for any file size.

Signed-off-by: Frederic Danis <frederic.danis@linux.intel.com>
Fixes: 9119fba0cf (serial: 8250_dma: don't bother DMA with small transfers)
Cc: stable@vger.kernel.org
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:24:46 -07:00
Heikki Krogerus
6ede6dcd87 serial: 8250_mid: add support for DMA engine handling from UART MMIO
The platforms that have this UART, but that don't have
separate PCI device for the DMA Engine, need to create the
HSU DMA Engine device separately.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:22:08 -07:00
Heikki Krogerus
ec2f1b67f5 dmaengine: hsu: make the UART driver in control of selecting this driver
HSU (High Speed UART) DMA engine, like the name suggests, is
an integrated DMA engine for UART and UART alone. Therefore,
making the UART drivers responsible of selecting it and
removing the user selectable option for it. The UARTs with
this DMA engine can always select HSU_DMA when
SERIAL_8250_DMA option is enabled.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:22:08 -07:00
Arnd Bergmann
1b306f997e serial: fix mctrl helper functions
A recent patch to create common helper functions for modem control
lines created empty helper functions in a header file, but accidentally
did not mark them as 'static inline', which causes build errors:

drivers/tty/serial/mxs-auart.o: In function `mctrl_gpio_enable_ms':
mxs-auart.c:(.text+0x171c): multiple definition of `mctrl_gpio_enable_ms'
drivers/tty/serial/clps711x.o:clps711x.c:(.text+0x768): first defined here
drivers/tty/serial/mxs-auart.o: In function `mctrl_gpio_disable_ms':
mxs-auart.c:(.text+0x1720): multiple definition of `mctrl_gpio_disable_ms'
drivers/tty/serial/clps711x.o:clps711x.c:(.text+0x76c): first defined here

This adds the missing annotation, so the functions do not get placed
in each object file.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: ce59e48fdb ("serial: mctrl_gpio: implement interrupt handling")
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:21:07 -07:00
Heikki Krogerus
d9eda9bab2 serial: 8250_pci: Intel MID UART support to its own driver
Intel MID UART quirks require already quite a bit of code
in 8250_pci.c. On new Intel platforms where it is used, the
integrated DMA engine no longer has its own PCI device, but
is instead configured from the UART's MMIO. That means we
will have to add even more code for handling just MID UARTs.

Instead of adding that to 8250_pci.c, splitting the support
of Intel MID UART into its own driver. Handling of the
integrated DMA engine becomes much simpler this way. Own
driver will also remove the need for things like specific
set_termios hooks for every board using this UART, and
simplify the handling of it in general.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:18:38 -07:00
Stefan Agner
1d59b382f1 serial: fsl_lpuart: add earlycon support
Add support for DT and command line based earlycon support for
lpuart and lpuart32 used on Freescale Vybrid and and QorIQ LS1021A
processors.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:18:30 -07:00
Paul Gortmaker
6200cbaf62 tty: disable unbind for old 74xx based serial/mpsc console port
We recently got rid of some modular code in this driver and also
got rid of the unused ".remove" function at the same time.  Thierry
noted that it was however possible to force the remove through the
bind/unbind interface.

Since this is a console device used on 2005 vintage 74xx based
powerpc embedded targets, and is essentially always used in
conjunction with SERIAL_MPSC_CONSOLE=y -- there is no sane reason
anyone would ever want to unbind the builtin driver and lose the
console.  So we just explicitly block bind/unbind operations and
prevent root from shooting themselves in the foot.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-serial@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:18:30 -07:00
Peter Hurley
b3868e20f4 n_tty: Remove reader wakeups for TTY_BREAK/TTY_PARITY chars
Waking the reader immediately upon receipt of TTY_BREAK or TTY_PARITY
chars has no effect on the outcome of read():
1. Only non-canonical/EXTPROC mode applies since canonical mode
   will not return data until a line termination is received anyway
2. EXTPROC mode - the reader will always be woken by the input worker
3. Non-canonical modes
   a. MIN == 0, TIME == 0
   b. MIN == 0, TIME > 0
   c. MIN > 0, TIME > 0
      minimum_to_wake is always 1 in these modes so the reader will always
      be woken by the input worker
   d. MIN > 0, TIME == 0
      although the reader will not be woken by the input worker unless the
      minimum data is received, the reader would not otherwise have
      returned the received data

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:18:30 -07:00
Jiri Slaby
4bd0162264 tty: synclink, fix indentation
The statement after if should be indenteted. So fix this.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:14:06 -07:00
Jiri Slaby
77bdec6f0f serial: at91, fix rs485 properties
There is a misplaced bracket in atmel_init_rs485 which sets
rs485-rx-during-tx and rs485-enabled-at-boot-time only if
rs485-rts-delay is set in of.

This is clearly a bug, so fix it by moving the bracket to the proper
place.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Elen Song <elen.song@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:14:06 -07:00
Peter Hurley
aba24888d9 tty: r3964: Replace/remove bogus tty lock use
The tty lock is strictly for serializing tty lifetime events
(open/close/hangup), and not for line discipline serialization.

The tty core already provides serialization of concurrent writes
to the same tty, and line discipline lifetime management (by ldisc
references), so pinning the tty via tty_lock() is unnecessary and
counter-productive; remove tty lock use.

However, the line discipline is responsible for serializing reads
(if required by the line discipline); add read_lock mutex to
serialize calls of r3964_read().

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:11:29 -07:00
Peter Hurley
9b9ab1b3f0 tty: r3964: Use tty->read_wait waitqueue
The tty core provides read_wait waitqueue specifically for line
disciplines to wait readers; otherwise, the line discipline may
miss wakeups generated by the tty core.

NB: The tty core already provides serialization for the line discipline's
close() method, and guarantees no readers or writers will be using the
closing instance of the line discipline. Completely remove that wakeup.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:11:29 -07:00
Peter Hurley
cc2aaabfd6 tty: Remove tty_port::close_wait
With the removal of tty_wait_until_sent_from_close(), tty drivers
no longer wait during open for parallel closes to complete (instead,
the tty core waits before calling the driver open() method). Thus,
the close_wait waitqueue is no longer used for waiting.

Remove struct tty_port::close_wait.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:11:29 -07:00
Peter Hurley
fef062cbf2 tty: Remove ASYNC_CLOSING checks in open()/hangup() methods
Since at least before 2.6.30, tty drivers that do not drop the tty lock
while closing cannot observe ASYNC_CLOSING set while holding the
tty lock; this includes the tty driver's open() and hangup() methods,
since the tty core calls these methods holding the tty lock.

For these drivers, waiting for ASYNC_CLOSING to clear while opening
is not required, since this condition cannot occur. Similarly, even
when the open() method drops and reacquires the tty lock after
blocking, ASYNC_CLOSING cannot be set (again, for drivers that
do not drop the tty lock while closing).

Now that tty port drivers no longer drop the tty lock while closing
(since 'tty: Remove tty_wait_until_sent_from_close()'), the same
conditions apply: waiting for ASYNC_CLOSING to clear while opening
is not required, nor is re-checking ASYNC_CLOSING after dropping and
reacquiring the tty lock while blocking (eg., in *_block_til_ready()).

Note: The ASYNC_CLOSING flag state is still maintained since several
bitrotting drivers use it for (dubious) other purposes.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:11:29 -07:00
Peter Hurley
79c1faa451 tty: Remove tty_wait_until_sent_from_close()
tty_wait_until_sent_from_close() drops the tty lock while waiting
for the tty driver to finish sending previously accepted data (ie.,
data remaining in its write buffer and transmit fifo).

tty_wait_until_sent_from_close() was added by commit a57a7bf3fc
("TTY: define tty_wait_until_sent_from_close") to prevent the entire
tty subsystem from being unable to open new ttys while waiting for
one tty to close while output drained.

However, since commit 0911261d4c ("tty: Don't take tty_mutex for tty
count changes"), holding a tty lock while closing does not prevent other
ttys from being opened/closed/hung up, but only prevents lifetime event
changes for the tty under lock.

Holding the tty lock while waiting for output to drain does prevent
parallel non-blocking opens (O_NONBLOCK) from advancing or returning
while the tty lock is held. However, all parallel opens _already_
block even if the tty lock is dropped while closing and the parallel
open advances. Blocking in open has been in mainline since at least 2.6.29
(see tty_port_block_til_ready(); note the test for O_NONBLOCK is _after_
the wait while ASYNC_CLOSING).

IOW, before this patch a non-blocking open will sleep anyway for the
_entire_ duration of a parallel hardware shutdown, and when it wakes, the
error return will cause a release of its tty, and it will restart with
a fresh attempt to open. Similarly with a blocking open that is already
waiting; when it's woken, the hardware shutdown has already completed
to ASYNC_INITIALIZED is not set, which forces a release and restart as
well.

So, holding the tty lock across the _entire_ close (which is what this
patch does), even while waiting for output to drain, is equivalent to
the current outcome wrt parallel opens.

Cc: Alan Cox <alan@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
CC: Arnd Bergmann <arnd@arndb.de>
CC: Karsten Keil <isdn@linux-pingi.de>
CC: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:11:29 -07:00
Jon Hunter
32ede4a517 serial: tegra: Add helper function for handling RX buffer
In the tegra UART driver there are three places where the RX DMA buffer
is handled and pushed up to the tty layer. In all three instances the
same functions are called and so instead of duplicating the code in three
places, move this code to a new helper function and use this new function.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:07:57 -07:00
Jon Hunter
b0e066ccb5 serial: tegra: Remove redundant code and check in tegra_uart_stop_rx()
The serial-tegra driver always uses DMA and hence the driver always
allocates DMA channels. Therefore, the test to see if the RX DMA channel
is initialised in tegra_uart_stop_rx() is unnecessary and so remove
the test and the code that corresponds to the case where the RX DMA
channel is not initialised. Please note that the call to
tegra_uart_stop_rx() should always be before the call to
tegra_uart_shutdown() which will uninitialise the RX DMA channel.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:07:57 -07:00
Jon Hunter
2230a9475f serial: tegra: Remove unnecessary return statements
Some functions in the serial-tegra driver have unnecessary return
statements at the end of a void function and so remove them.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:07:57 -07:00
Jon Hunter
2a24bb28a3 serial: tegra: Handle another RX race condition
Commit 853a699739 ("serial: tegra: handle race condition on uart rx
side") attempted to fix a race condition between the RX end of
transmission interrupt and RX DMA completion callback. Despite this
fix there is still another case where these two paths can race and
result in duplicated data. The race condition is as follows:

1. DMA completion interrupt occurs and schedules tasklet to call DMA
   callback.
2. DMA callback for the UART driver starts to execute. This will copy
   the data from the DMA buffer and restart the DMA. This is done under
   uart port spinlock.
3. During the callback, UART interrupt is raised for end of receive. The
   UART ISR runs and waits to acquire port spinlock held by the DMA
   callback.
4. DMA callback gives up spinlock after copying the data, but before
   restarting DMA.
5. UART ISR acquires the spin lock and reads the same DMA buffer because
   DMA has not been restarted yet.

The release of the spinlock during the DMA callback was introduced by
commit 9b88748b36 ("tty: serial: tegra: drop uart_port->lock before
calling tty_flip_buffer_push()") to fix a spinlock lock-up issue when
calling tty_flip_buffer_push(). However, since then commit a9c3f68f3c
("tty: Fix low_latency BUG") migrated tty_flip_buffer_push() to always
use a workqueue, allowing tty_flip_buffer_push() to be called from
within atomic sections. Therefore, we can remove the unlocking of the
spinlock from the DMA callback and UART ISR and this will ensure that
the race condition no longer occurs.

Reported-by: Christopher Freeman <cfreeman@nvidia.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:07:57 -07:00
Peter Hurley
0abcc6df07 serial: 8250_omap: Remove RTS clear
Clearing UART_MCR_RTS or UART_MCR_XONANY is unnecessary; these bits
are never set in the shadow mcr. The RTS clear is especially confusing.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:05:46 -07:00
Scott Wood
d43b54d269 serial: Enable Freescale 16550 workaround on arm
The same serial hardware is present on LS2080A which is arm64, and
LS1021A which is arm32, so don't limit the workaround to PPC.

Unlike PPC which uses arch/powerpc/kernel/legacy_serial.c, the ARM
targets use drivers/tty/serial/of_serial.c, so add the handle_irq
override check there as well.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:05:46 -07:00
Andreas Werner
37f0679964 tty: serial: men_z135_uart.c: use mcb memory region size instead of hardcoded one
There is no need to hardcode the MEN_Z135_MEM_SIZE. The MCB subsystem
already knowns the size which is located in the chameleon table.
MCB parse the chameleon table to get the resources of each IP and provide
the mcb_request_mem function to get those resources.

Use mcb_request_mem to get the resources. This function also takes care of
the memory region naming allocated by the driver for each of the instances.

Signed-off-by: Andreas Werner <andy@wernerandy.de>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:05:43 -07:00
Andre Przywara
270c2adef3 serial: atmel: fix compiler warning on address cast
Turning on KVM and LPAE support on top of a multi_v7_defconfig will
produce a compiler warning in the Atmel serial driver:
drivers/tty/serial/atmel_serial.c: In function 'atmel_verify_port':
drivers/tty/serial/atmel_serial.c:2299:6: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
  if ((void *)port->mapbase != ser->iomem_base)
      ^

Fix that by using the cast on the right hand side instead, as similar
code already does in other drivers.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:00:11 -07:00
Christoph Hellwig
eecbf54fdd n_tracesink: stop including <asm-generic/bug>
<asm-generic/bug> contains the default implementation of BUG() and friends,
which architectures may decide to use.  The proper way to get them is
<linux/bug.h>, so use that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-10-15 00:21:11 +02:00
Christoph Hellwig
c7b918050d n_tracerouter: stop including <asm-generic/bug>
<asm-generic/bug> contains the default implementation of BUG() and friends,
which architectures may decide to use.  The proper way to get them is
<linux/bug.h>, so use that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-10-15 00:21:10 +02:00
Greg Kroah-Hartman
378102f364 Merge 4.3-rc5 into tty-next
We want the tty fixes and reverts in here as well so that people can
properly test and use it.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-12 10:54:35 -07:00
Jann Horn
0c55627167 drivers/tty: require read access for controlling terminal
This is mostly a hardening fix, given that write-only access to other
users' ttys is usually only given through setgid tty executables.

Signed-off-by: Jann Horn <jann@thejh.net>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:20:30 +01:00
Mans Rullgard
3c5a0357fd serial: 8250: add uart_config entry for PORT_RT2880
This adds an entry to the uart_config table for PORT_RT2880
enabling rx/tx FIFOs.  The UART is actually a Palmchip BK-3103
which is found in several devices from Alchemy/RMI, Ralink, and
Sigma Designs.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:16:12 +01:00
Ivan T. Ivanov
850b37a71b tty: serial: msm: Remove 115.2 Kbps maximum baud rate limitation
UART controller is capable to perform transfers up to 4 Mbps.
Remove artificial 115.2 Kbps limitation.

Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:15:17 +01:00
Ivan T. Ivanov
9969394501 tty: serial: msm: Add RX DMA support
Add receive DMA support for UARTDM type of controllers.

Tested on APQ8064, which have UARTDM v1.3 and ADM DMA engine
and APQ8016, which have UARTDM v1.4 and BAM DMA engine.

Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:15:17 +01:00
Ivan T. Ivanov
3a878c430f tty: serial: msm: Add TX DMA support
Add transmit DMA support for UARTDM type of controllers.

Tested on APQ8064, which have UARTDM v1.3 and ADM DMA engine
and APQ8016, which have UARTDM v1.4 and BAM DMA engine.

Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:15:17 +01:00
Ivan T. Ivanov
558abdb05f tty: serial: msm: Add msm prefix to all driver functions
Make function naming consistent across this driver.
Also rename msm_irq to msm_uart_irq. No functional changes.

Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:15:17 +01:00
Pramod Gurav
eec43b8afa tty: serial: msm: replaces (1 << x) with BIT(x) macro
Replaces (1 << x) with BIT(x) macro

Signed-off-by: Pramod Gurav <gpramod@codeaurora.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:15:17 +01:00
Pramod Gurav
12b9b9f186 tty: serial: msm: Add mask value for UART_DM registers
The bit masks for RFR_LEVEL1 and STALE_TIMEOUT_MSB values in MR1 and
IPR registers respectively are different for UART and UART_DM hardware
cores. We have been using UART core mask values for these. Add the same
for UART_DM core.

There is no bit setting as UART_IPR_RXSTALE_LAST for UART_DM core so do
it only for UART core.

Signed-off-by: Pramod Gurav <gpramod@codeaurora.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:15:17 +01:00
Sean Nyekjaer
2b0159d1ec sc16is7xx: null ptr check
If a wrong compatible flag in specified, the of_match_device
returning null.
Implemented check and if NULL then returning -ENODEV.

Signed-off-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:14:26 +01:00
Ezequiel Garcia
adfb9233e4 serial: omap: remove warnings about unused functions
They're used by only if CONFIG_PM is enabled, so enclose them
with proper ifdefs. Removes these warnings:

drivers/tty/serial/omap-serial.c:202:12: warning: 'serial_omap_get_context_loss_count' defined but not used [-Wunused-function]
drivers/tty/serial/omap-serial.c:213:13: warning: 'serial_omap_enable_wakeup' defined but not used [-Wunused-function]

Signed-off-by: Guido Martínez <guido@vanguardiasur.com.ar>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:14:26 +01:00
Christoph Hellwig
fc12c116b1 mpsc: use dma_set_mask insted of dma_supported
This ensures the dma mask that is supported by the driver is recorded
in the device structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:14:26 +01:00
Andy Shevchenko
27c310c5c3 serial: 8250_dma: no need to sync RX buffer
RX buffer is allocated from DMA coherent memory. Thus there is no need to call
DMA sync API for it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:12:25 +01:00
Peter Hurley
10791233e9 serial: 8250: Refactor serial console restore-from-suspend
Move h/w reinit of serial console restore-from-suspend into
standalone helper function.

No functional change.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:12:25 +01:00
James Hogan
4f56f3fdca serial: 8250: Tolerate clock variance for max baud rate
When the UART clock is set slightly under 1.8432MHz, the 8250 driver
core doesn't permit the 115200 baud rate since it calculates the maximum
frequency to pass to uart_get_baud_rate by simply dividing the uart
clock by 16 which yields a value slightly under 115200, even though the
frequency is close enough for the UART to operate reliably.

Therefore add some tolerance in the calculation of the maximum baud
rate. 1% tolerance allows for marginally slower uart clk than nominal
without introducing transmission errors.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
[pjh: Forward-port & refactor original patch; change tolerance to 1%]
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:12:25 +01:00
Max Filippov
d215d80957 serial_core: support native endianness
There are three natural ways in which devices may be wired to the system:
little endian (device receives correctly ordered bits of a word written
by little-endian CPU to its register, but big-endian CPU needs to swap
bytes of a word before writing it), big endian (same, but with big-endian
CPU in more favourable position) and native endian (CPU of either
endianness may do word-sized I/O without need for byteswapping).

Adding an option for native endianness allows using single kernel command
line for boards with native-endian serial ports on bi-endian
architectures. This goes in parallel with 'native-endian' DTS attribute.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:11:05 +01:00
Sudeep Holla
616ea8d2d6 tty/serial: st-asc: drop the use of IRQF_NO_SUSPEND
These drivers doesn't claim the serial device to be wakeup source. Even
if it is, it needs to use enable_irq_wake or other related PM wakeup
APIs to enable it.

This patch removes yet another misuse of IRQF_NO_SUSPEND.

Cc: Srinivas Kandagatla <srinivas.kandagatla@gmail.com>
Cc: Maxime Coquelin <maxime.coquelin@st.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: kernel@stlinux.com
Cc: linux-serial@vger.kernel.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:11:05 +01:00
Sudeep Holla
b801e7f898 MIPS: ttyFDC: replace IRQF_NO_SUSPEND with IRQF_COND_SUSPEND
Since the FD interrupt handler can discern spurious IRQs and it is
shared with timer interrupt, use IRQF_COND_SUSPEND instead of
IRQF_NO_SUSPEND.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:11:05 +01:00
Andrzej Hajda
14996122a4 tty: serial: lpc32xx_hs: fix handling platform_get_irq result
The function can return negative values.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2038576

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:09:21 +01:00
Luis de Bethencourt
618bbaa260 tty: serial: cpm_uart: Fix module autoload for OF platform driver
This platform driver has a OF device ID table but the OF module
alias information is not created so module autoloading won't work.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Acked-by: Timur Tabi <timur@tabi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:09:21 +01:00
Luis de Bethencourt
7edb23ce46 tty: serial: sprd: Fix module autoload for OF platform driver
This platform driver has a OF device ID table but the OF module
alias information is not created so module autoloading won't work.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:09:21 +01:00
Luis de Bethencourt
8d58db1ede tty: serial: of_serial: Fix module autoload for OF platform driver
This platform driver has a OF device ID table but the OF module
alias information is not created so module autoloading won't work.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:09:21 +01:00
Luis de Bethencourt
50a84487c3 tty: serial: apbuart: Fix module autoload for OF platform driver
This platform driver has a OF device ID table but the OF module
alias information is not created so module autoloading won't work.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:09:21 +01:00
Mans Rullgard
9b2256c827 serial: 8250: simplify ralink/alchemy register remap selection
Some SoCs, including Ralink/Mediatek and Alchemy Au1xxx, have a
16550-like UART with a non-standard register layout.  These are
supported by a simple mapping table in 8250_port.c  Rather than
list every SoC type using this access mode in the ifdefs there,
allow selecting the SERIAL_8250_RT288X Kconfig option with any
system and default it to y for the known cases needing it.  The
help text is reworded accordingly.

This change simplifies adding support for other SoCs also using
the same UART.

The name of the option is a little misleading, but not knowing
the true origin of this UART, it is as good a choice as any.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:09:21 +01:00
Dmitry Vyukov
facd885c75 tty: fix data race on tty_buffer.commit
Race on buffer data happens when newly committed data is
picked up by an old flush work in the following scenario:
__tty_buffer_request_room does a plain write of tail->commit,
no barriers were executed before that.
At this point flush_to_ldisc reads this new value of commit,
and reads buffer data, no barriers in between.
The committed buffer data is not necessary visible to flush_to_ldisc.

Similar bug happens when tty_schedule_flip commits data.

Update commit with smp_store_release and read commit with
smp_load_acquire, as it is commit that signals data readiness.
This is orthogonal to the existing synchronization on tty_buffer.next,
which is required to not dismiss a buffer with unconsumed data.

The data race was found with KernelThreadSanitizer (KTSAN).

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:03:40 +01:00
Dmitry Vyukov
9e6b7cd7e7 tty: fix data race in tty_buffer_flush
tty_buffer_flush frees not acquired buffers.
As the result, for example, read of b->size in tty_buffer_free
can return garbage value which will lead to a huge buffer
hanging in the freelist. This is just the benignest
manifestation of freeing of a not acquired object.
If the object is passed to kfree, heap can be corrupted.

Acquire visibility over the buffer before freeing it.

The data race was found with KernelThreadSanitizer (KTSAN).

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:03:40 +01:00
Dmitry Vyukov
7098296a36 tty: fix data race in flush_to_ldisc
flush_to_ldisc reads port->itty and checks that it is not NULL,
concurrently release_tty sets port->itty to NULL. It is possible
that flush_to_ldisc loads port->itty once, ensures that it is
not NULL, but then reloads it again and uses. The second load
can already return NULL, which will cause a crash.

Use READ_ONCE to read port->itty.

The data race was found with KernelThreadSanitizer (KTSAN).

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:03:40 +01:00
Kosuke Tatsukawa
e81107d4c6 tty: fix stall caused by missing memory barrier in drivers/tty/n_tty.c
My colleague ran into a program stall on a x86_64 server, where
n_tty_read() was waiting for data even if there was data in the buffer
in the pty.  kernel stack for the stuck process looks like below.
 #0 [ffff88303d107b58] __schedule at ffffffff815c4b20
 #1 [ffff88303d107bd0] schedule at ffffffff815c513e
 #2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818
 #3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2
 #4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23
 #5 [ffff88303d107dd0] tty_read at ffffffff81368013
 #6 [ffff88303d107e20] __vfs_read at ffffffff811a3704
 #7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57
 #8 [ffff88303d107f00] sys_read at ffffffff811a4306
 #9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7

There seems to be two problems causing this issue.

First, in drivers/tty/n_tty.c, __receive_buf() stores the data and
updates ldata->commit_head using smp_store_release() and then checks
the wait queue using waitqueue_active().  However, since there is no
memory barrier, __receive_buf() could return without calling
wake_up_interactive_poll(), and at the same time, n_tty_read() could
start to wait in wait_woken() as in the following chart.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
if (waitqueue_active(&tty->read_wait))
/* Memory operations issued after the
   RELEASE may be completed before the
   RELEASE operation has completed */
                                        add_wait_queue(&tty->read_wait, &wait);
                                        ...
                                        if (!input_available_p(tty, 0)) {
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

The second problem is that n_tty_read() also lacks a memory barrier
call and could also cause __receive_buf() to return without calling
wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken()
as in the chart below.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
                                        spin_lock_irqsave(&q->lock, flags);
                                        /* from add_wait_queue() */
                                        ...
                                        if (!input_available_p(tty, 0)) {
                                        /* Memory operations issued after the
                                           RELEASE may be completed before the
                                           RELEASE operation has completed */
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
if (waitqueue_active(&tty->read_wait))
                                        __add_wait_queue(q, wait);
                                        spin_unlock_irqrestore(&q->lock,flags);
                                        /* from add_wait_queue() */
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

There are also other places in drivers/tty/n_tty.c which have similar
calls to waitqueue_active(), so instead of adding many memory barrier
calls, this patch simply removes the call to waitqueue_active(),
leaving just wake_up*() behind.

This fixes both problems because, even though the memory access before
or after the spinlocks in both wake_up*() and add_wait_queue() can
sneak into the critical section, it cannot go past it and the critical
section assures that they will be serialized (please see "INTER-CPU
ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a
better explanation).  Moreover, the resulting code is much simpler.

Latency measurement using a ping-pong test over a pty doesn't show any
visible performance drop.

Signed-off-by: Kosuke Tatsukawa <tatsu@ab.jp.nec.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 19:03:40 +01:00
Uwe Kleine-König
8f1bd8f2ad serial: atmel: fix error path of probe function
If atmel_init_gpios fails the port has already been marked as busy (in
line 2629), so this must be undone in the error path.

This bug was introduced because I created the patch that finally
became 722ccf416a ("serial: atmel: fix error handling when
mctrl_gpio_init fails") on top of 3.19 which didn't have commit
6fbb9bdf0f ("tty/serial: at91: fix error handling in
atmel_serial_probe()") yet.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Fixes: 722ccf416a ("serial: atmel: fix error handling when mctrl_gpio_init fails")
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:51:42 +01:00
Leon Yu
c1a752ba2d tty: don't leak cdev in tty_cdev_add()
Commit a3a10ce342 ("Avoid usb reset crashes by making tty_io cdevs truly
dynamic") which mixes using cdev_alloc() and cdev_init() is problematic.
Subsequent call to cdev_init() after cdev_alloc() sets kobj release method
from cdev_dynamic_release() to cdev_default_release() and thus makes it
impossible to free allocated cdev.

This patch also consolidates error path of cdev_add() as cdev can also leak
here if things went wrong.

Signed-off-by: Leon Yu <chianglungyu@gmail.com>
Fixes: a3a10ce342 ("Avoid usb reset crashes by making tty_io cdevs truly dynamic")
Acked-by: Richard Watts <rrw@kynesim.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:51:42 +01:00
Fabio Estevam
0c727a4204 Revert "serial: imx: remove unbalanced clk_prepare"
This reverts commit 9e7b399d65.

Commit ("9e7b399d6528ea") causes the following warning and sometimes
also hangs the system:

------------[ cut here ]------------
 WARNING: CPU: 0 PID: 0 at kernel/locking/mutex.c:868 mutex_trylock+0x20c/0x22c()
 DEBUG_LOCKS_WARN_ON(in_interrupt())
 Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.2.0-rc7-next-20150818-00001-g14418a6 #4
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
Backtrace:
[<80012f08>] (dump_backtrace) from [<800130a4>] (show_stack+0x18/0x1c)
r6:00000364 r5:00000000 r4:00000000 r3:00000000
[<8001308c>] (show_stack) from [<807902b8>] (dump_stack+0x88/0xa4)
[<80790230>] (dump_stack) from [<8002a604>] (warn_slowpath_common+0x80/0xbc)
r5:807945c4 r4:80ab3b50
[<8002a584>] (warn_slowpath_common) from [<8002a6e4>] (warn_slowpath_fmt+0x38/0x40)
r8:00000000 r7:8131100c r6:8054c3cc r5:8131300c r4:80b0a570
[<8002a6b0>] (warn_slowpath_fmt) from [<807945c4>] (mutex_trylock+0x20c/0x22c)
r3:8095d0d8 r2:8095ab28
[<807943b8>] (mutex_trylock) from [<8054c3cc>] (clk_prepare_lock+0x14/0xf4)
r7:8131100c r6:be3f0c80 r5:00000037 r4:be3f0c80
[<8054c3b8>] (clk_prepare_lock) from [<8054dbfc>] (clk_prepare+0x18/0x30)
r5:00000037 r4:be3f0c80
[<8054dbe4>] (clk_prepare) from [<8036a600>] (imx_console_write+0x30/0x244)
r4:812d0bc8 r3:8132b9a4

To reproduce the problem we only need to let the board idle for something
like 30 seconds.

Tested on a imx6q-sabresd.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:51:42 +01:00
Uwe Kleine-König
ce59e48fdb serial: mctrl_gpio: implement interrupt handling
This allows to reduce the per-driver boiler plate considerably.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:47:51 +01:00
Uwe Kleine-König
7d8c70d804 serial: mctrl-gpio: rename init function
This is done before adding more functionality to the init function with
the existing name. As this new functionality conflicts with stuff
drivers are required to implement themselves up to I want to convert
them one by one to make reviewing and reverting more easy in case I
broke something.

Once mctrl_gpio_init is there and all drivers are converted
mctrl_gpio_init_noauto can be removed again.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:46:43 +01:00
Uwe Kleine-König
dc2454f7eb serial: mxs-auart+imx: allow compile testing on non-Freescale architectures
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:46:43 +01:00
Uwe Kleine-König
c8d1f02245 serial: atmel: allow compile testing on non-atmel architectures
This commit also fixes compiler warnings and errors seen when building
on x86_64.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:45:18 +01:00
Lucas Stach
abc7882aac serial: imx: also update RX stats in DMA path
The RX bytecount was only updated in the PIO path and thus
the device erroneously reported a value of 0 if DMA is in
use.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:44:29 +01:00
Lucas Stach
7e11577ef6 serial: imx: re-enable DMA support without hardware flow control
The commit enabling DMA support even if no flow control is present
was reverted on the grounds that it uncovered a number of bugs in
the code that lead to hanging tty devices and/or missing characters.

After tracking down the issues it is clear that those were generic
bugs and had nothing to do with flow control being present or not,
only that allowing DMA without hardware flow control increased
the exposure of that code a lot.

Now that those bugs are fixed, it should be safe to re-enable DMA
support.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:43:30 +01:00
Lucas Stach
905c0decad serial: imx: don't use idle condition detect for DMA transfers
The reference manual states that idle condition detect should not be used
with DMA transfers, as the ROM SDMA scripts don't check those conditions.

The RAM SDMA scripts worked around this, but the change broke compatibility
with the ROM scripts.

The previous commits fixed the DMA burst sizes, so that the aging timer is
now working as described in the reference manual. With this fixed we can
remove the hack of using the idle condition detect to stop the DMA transfer
if there are no new characters incoming.

This should work with both the ROM and RAM SDMA scripts.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:43:06 +01:00
Lucas Stach
184bd70bbc serial: imx: configure proper DMA burst sizes
Triggering the DMA engine for every byte is horribly inefficient.
Also it doesn't allow to use the aging timer for the RX FIFO as this
requires the DMA engine to leave one byte remaining in the FIFO when
doing a normal burst transfer.

Adjust watermark levels so that the DMA engine can do at least 8 byte
burst transfers. This is a conservative value, as the both TX and RX
FIFOs are able to contain 32 bytes.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:43:06 +01:00
Lucas Stach
976b39cd5b serial: imx: always restart DMA if more data is available
Simplify the DMA restart logic to always queue up the next transfer
immediately if there is at least one more byte available in the FIFO,
so that the transfer will finish in a limited time.

This way the driver stops to rely on zero length transfers to signal
transfers ends. Those will go away when the idle detect DMA requests
are disabled.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:42:26 +01:00
Lucas Stach
86a04ba642 serial: imx: set up aging timer interrupt as DMA trigger
The DMA transfer is only started once we are sure it will finish
in a limited time, i.e. only after we received a RRDY interrupt.

In order to allow the watermark level to be raised the aging
timer and the corresponding interrupt need to be set up as an
additional trigger, so that the transfer is also started if the
incoming amount of bytes never reach the watermark.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:41:09 +01:00
Lucas Stach
cc32382d9f serial: imx: make setup_ufcr more useful
This function currently doesn't use its parameter.

Change prototype to pass in watermark levels, so we can reuse this
function in the DMA setup paths. Also relocate to be near the calling
functions.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:41:09 +01:00
Heikki Krogerus
7693c79ce0 serial: 8250_dw: don't set UPF_BOOT_AUTOCONF flag
serial8250_register_8250_port adds it to all ports it
registers. No need to set it separately.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:38:45 +01:00
Heikki Krogerus
2338a75e0f serial: 8250_dw: cleanup dw8250_setup_port
Using the same style of declaring variables as used in the
other functions of the driver. Passing uart_port to the
function instead of uart_8250_port, as it is the one mostly
needed.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:38:45 +01:00
Heikki Krogerus
83ce95ef5e serial: 8250_dw: cleanup dw8250_idma_filter
Remove the extra return.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:38:45 +01:00
Heikki Krogerus
1edb3cf21f serial: 8250_dw: rename and comment the fallback dma filter
Adding comment where the purpose of the function is
explained.

The dma parameters are not used, so removing them, and also
moving the assignment of the function to the same place
where the other dw8250_data structures members are being set
in dw8250_probe.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:38:45 +01:00
Heikki Krogerus
c73942e22a serial: 8250_dw: proper support for UARTs without busy functionality
If the DW_apb_uart is configured with UART_16550_COMPATIBLE
configuration parameter set, then the Busy Functionality is
not available. These UARTs will never generate the Busy
detect indication interrupt, and therefore don't need
handling for it.

This creates a small optimization for the DW_apb_uarts
configured without the busy functionality, but more
importantly, it removes the small but real risk of hitting
potential issues caused by busy functionality handling when
no busy functionality exist.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:38:45 +01:00
Heikki Krogerus
9e08fa50b2 serial: 8250_dw: add dw8250_quirks function
Merging the DT and ACPI specific probe functions into
dw8250_quirks. Those functions did not have that much code
any more and some of the quirks need to be shared. This
will also allow platforms without DT or ACPI to use the
driver.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:38:45 +01:00
Heikki Krogerus
4f042054fa serial: 8250_dw: only setup the port from one place
This adds a flag "skip_autocfg" that the platforms that do
not have the ADDITIONAL_FEATURES implemented can use to skip
the port setup. It's then enough to call dw8250_setup_port
just from dw8250_probe based on that flag.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:38:45 +01:00
Heikki Krogerus
2559318caa serial: 8250_dw: hook the DMA in one place
Instead of assigning the dma member in dw8250_probe_of and
dw8250_probe_acpi separately, assigning it in dw8250_probe.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:38:45 +01:00
Heikki Krogerus
1bd8edba10 serial: 8250_dw: adapt to unified device property interface
This makes the properties available for all types of
platforms instead of just the ones using DT.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:38:45 +01:00
Heikki Krogerus
78d3da75d5 serial: 8250_dw: add separate pointer for the uart_port to dw8250_probe
For convenience, adding separate pointer for the "port"
member of struct uart_8250_port that is being filled in the
probe function.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 18:38:45 +01:00
Scott Wood
d05f15707b serial: 8250: Add OF earlycon support
This allows earlycon to be used without needing to specify the I/O
address on the kernel command line, if linux,stdout-path is specified
in the chosen node.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 17:49:27 +01:00
Lucas Stach
913c6c0e94 serial: imx: add earlycon support
Earlycon allows to have an early debugging console that doesn't need
to be statically configured in the kernel config, like earlyprintk,
but is set up through the stdout-path DT property.

This allows to have the early debugging always built into the
kernel and enabled on demand without clashing between different boards
or architectures.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 17:49:27 +01:00
Abhimanyu Kapur
4cad4c57e0 ARM64: TTY: hvc_dcc: Add support for ARM64 dcc
Add support for debug communications channel based
hvc console for arm64 cpus.

Signed-off-by: Abhimanyu Kapur <abhimany@codeaurora.org>
Signed-off-by: Timur Tabi <timur@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 17:49:27 +01:00
Timur Tabi
3d27070108 hvc_dcc: don't ignore errors during initialization
hvc_instantiate() and hvc_alloc() return errors if they fail, so don't
ignore them.

Signed-off-by: Timur Tabi <timur@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 17:49:27 +01:00
Alexandre Belloni
9af92fbff3 tty/serial: at91: move ATMEL_MAX_UART
Move ATMEL_MAX_UART from platform_data/atmel.h to atmel_serial.c as this is
the only file using it and it is common practise from tty/serial drivers to
define it directly in the driver file.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 17:47:49 +01:00
Martin Sperl
ed4492fa91 serial: of-serial: compile correctly when 8250 driver is compiled as module
If the 8250 driver is compiled as a module then
CONFIG_SERIAL_8250_MODULE is defined and not CONFIG_SERIAL_8250.

This results in all those code sections that require CONFIG_SERIAL_8250
to be defined are not included.

This patch fixes the situation and allows 8250 and of-serial to
be compiled as a module with the same functionality as when
compiled into the kernel.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 17:47:49 +01:00
Tobias Klauser
d144aff136 serial: altera_uart: Use of_property_read_u32 instead of open-coding it
Use of_property_read_u32 instead of of_get_property with return value
checks and endianness conversion. Also remove the !CONFIG_OF
implementation of altera_uart_get_of_uartclk as of_property_read_u32
will return a non-zero value for !CONFIG_OF.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 17:47:49 +01:00