Previously the timers where based on the classic timers, giving a too
coarse resolution on systems with configs of less than 1000 HZ.

This patch changes the rs485 timers to hrtimers.
Signed-off-by: NRafael Gago Castano <rgc@hms.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Previously the rs485 settings weren't considered when setting the RTS
line, so e.g. closing and reopening a port made serial_core to drive
the line as if rs485 was disabled.

This patch fixes those issues.
Signed-off-by: NRafael Gago Castano <rgc@hms.se>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR
Signed-off-by: NHimanshu Jha <himanshujha199640@gmail.com>
Reviewed-by: NMatthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use more compact of_property_read_bool() call for a boolean property
instead  of of_find_property() call in sci_parse_dt().
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It used to be a gap in port definitions after PORT_MAX_8250. Since the
new drivers are coming the gap become shorter and shorter until the
commit a2d6a987 ("serial: 8250: Add new port type for TI DA8xx/66AK2x")
completely removed it.

So, while type here is just a formality, make things a little bit more
explicit for this driver and move port types to UAPI header. Note,
it uses two types for now.

Fixes: fddceb8b ("tty: 8250: Add 64byte UART support for FSL platforms")
Cc: Priyanka Jain <Priyanka.Jain@freescale.com>
Cc: Poonam Aggrwal <poonam.aggrwal@freescale.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is no need to duplicate a flag which IRQ core takes care of.

Replace custom flag by IRQ core API that retrieves its state.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is no need to duplicate a flag which IRQ core takes care of.

Replace custom flag by IRQ core API that retrieves its state.

Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is no need to duplicate a flag which IRQ core takes care of.

Replace custom flag by IRQ core API that retrieves its state.

Cc: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is no need to duplicate a flag which IRQ core takes care of.

Replace custom flag by IRQ core API that retrieves its state.

Cc: Bhuvanchandra DV <bhuvanchandra.dv@toradex.com>
Cc: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Move the request_irq() call to the end of the msm_startup(),
so that we don't handle interrupts while msm_startup() is
running. This avoids potential races while initialization
is in progress. For example, consider below scenario
where rx handler reads the intermediate value of dma->chan,
set in msm_request_rx_dma(), and tries to do dma mapping,
which results in data abort.

uart_port_startup()
  msm_startup()
   request_irq()
   ...
   msm_request_rx_dma()
    ...
    dma->chan = dma_request_slave_channel_reason(dev, "rx");
    <UART RX IRQ>
     msm_uart_irq()
      msm_handle_rx_dm()
       msm_start_rx_dma()
        dma->desc = dma_map_single()
         <data abort>
Signed-off-by: NNeeraj Upadhyay <neeraju@codeaurora.org>
Reviewd-by: NAndy Gross <andy.gross@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is no need to do a NULL check for debugfs_remove().

Quoting Documentation/filesystems/debugfs.txt:

"The dentry value can be NULL, in which case nothing will be removed."

, so remove the unneeded NULL check.
Signed-off-by: NFabio Estevam <festevam@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

platform_get_irq() returns an error code, but the sprd_serial driver
ignores it and always returns -ENODEV. This is not correct and,
prevents -EPROBE_DEFER from being propagated properly.

Also, notice that platform_get_irq() no longer returns 0 on error:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e330b9a6bb35dc7097a4f02cb1ae7b6f96df92af

Print and propagate the return value of platform_get_irq on failure.

This issue was detected with the help of Coccinelle.
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

These uart_ops structures are only stored in the ops field of a
uart_port structure and this fields is const, so the uart_ops
structures can also be const.

Done with the help of Coccinelle.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

These uart_ops structures are only stored in the ops field of a
uart_port structure and this fields is const, so the uart_ops
structures can also be const.

Done with the help of Coccinelle.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

100µs was too short for low speed transmission
(9600bps)
Signed-off-by: NGerald Baeza <gerald.baeza@st.com>
Signed-off-by: NBich Hemon <bich.hemon@st.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

amba_id are not supposed to change at runtime. All functions
working with const amba_id. So mark the non-const structs as const.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

amba_id are not supposed to change at runtime. All functions
working with const amba_id. So mark the non-const structs as const.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

These vendor_data structures are only stored in the vendor field of
the uart_amba_port structure, as defined in the same file, and this
field is declared as const.  Thus the vendor_data structures can be
const too.

Done with the help of Coccinelle.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Sergey noticed a small but fatal mistake in __tty_insert_flip_char,
leading to an oops in an interrupt handler when using any serial
port.

The problem is that I accidentally took the tty_buffer pointer
before calling __tty_buffer_request_room(), which replaces the
buffer. This moves the pointer lookup to the right place after
allocating the new buffer space.

Fixes: 979990c6 ("tty: improve tty_insert_flip_char() fast path")
Reported-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 1104321a.

The code is not dead at all and breaks winbond-cir.

Serial: 8250/16550 driver, 32 ports, IRQ sharing enabled
00:02: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
00:03: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a CIR port
lirc lirc0: lirc_dev: driver ir-lirc-codec (winbond-cir) registered at minor = 0
winbond-cir 00:03: Region 0x2f8-0x2ff already in use!
winbond-cir: probe of 00:03 failed with error -16
Signed-off-by: NSean Young <sean@mess.org>
Reviewed-by: NMatthias Brugger <mbrugger@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The device-specific property should be prefixed with the vendor name,
not "linux,", as Linus Walleij pointed out. Change this and document the
bindings of this platform device.

We didn't ship the old binding in a release yet. So we can still change
it without breaking an official API.

Fixes: 380b1e2f ("gpio-exar/8250-exar: Make set of exported GPIOs configurable")
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The work-around for Qualcomm Technologies QDF2400 Erratum 44 hinges on a
global variable defined in the pl011 driver.  The ACPI SPCR parsing code
determines whether the work-around is needed, and if so, it changes the
console name from "pl011" to "qdf2400_e44".  The expectation is that
the pl011 driver will implement the work-around when it sees the console
name.  The global variable qdf2400_e44_present is set when that happens.

The problem is that work-around needs to be enabled when the pl011
driver probes, not when the console name is queried.  However, sbsa_probe()
is called before pl011_console_match().  The work-around appeared to work
previously because the default console on QDF2400 platforms was always
ttyAMA1.  The first time sbsa_probe() is called (for ttyAMA0),
qdf2400_e44_present is still false.  Then pl011_console_match() is called,
and it sets qdf2400_e44_present to true.  All subsequent calls to
sbsa_probe() enable the work-around.

The solution is to move the global variable into spcr.c and let the
pl011 driver query it during probe time.  This works because all QDF2400
platforms require SPCR, so parse_spcr() will always be called.
pl011_console_match still checks for the "qdf2400_e44" console name,
but it doesn't do anything else special.

Fixes: 5a0722b8 ("tty: pl011: use "qdf2400_e44" as the earlycon name for QDF2400 E44")
Tested-by: NJeffrey Hugo <jhugo@codeaurora.org>
Signed-off-by: NTimur Tabi <timur@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

While working on improving the fast path of tty_insert_flip_char(),
I noticed that by calling tty_buffer_request_room(), we needlessly
move to the separate flag buffer mode for the tty, even when all
characters use TTY_NORMAL as the flag.

This changes the code to call __tty_buffer_request_room() with the
correct flag, which will then allocate a regular buffer when it rounds
out of space but no special flags have been used. I'm guessing that
this is the behavior that Peter Hurley intended when he introduced
the compacted flip buffers.

Fixes: acc0f67f ("tty: Halve flip buffer GFP_ATOMIC memory consumption")
Cc: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

kernelci.org reports a crazy stack usage for the VT code when CONFIG_KASAN
is enabled:

drivers/tty/vt/keyboard.c: In function 'kbd_keycode':
drivers/tty/vt/keyboard.c:1452:1: error: the frame size of 2240 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]

The problem is that tty_insert_flip_char() gets inlined many times into
kbd_keycode(), and also into other functions, and each copy requires 128
bytes for stack redzone to check for a possible out-of-bounds access on
the 'ch' and 'flags' arguments that are passed into
tty_insert_flip_string_flags as a variable-length string.

This introduces a new __tty_insert_flip_char() function for the slow
path, which receives the two arguments by value. This completely avoids
the problem and the stack usage goes back down to around 100 bytes.

Without KASAN, this is also slightly better, as we don't have to
spill the arguments to the stack but can simply pass 'ch' and 'flag'
in registers, saving a few bytes in .text for each call site.

This should be backported to linux-4.0 or later, which first introduced
the stack sanitizer in the kernel.

Cc: stable@vger.kernel.org
Fixes: c420f167 ("kasan: enable stack instrumentation")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The struct serial_rs485 parameter is both input and output and is
supposed to hold the actually used configuration on return. So clear
unsupported settings.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If the board we are guessing has been listed in black list we don't need
to enable it twice. The associated driver, if any, will take care about
proper initialization.

To achieve this we split out two helper functions, i.e.
serial_pci_is_class_communication() and serial_pci_is_blacklisted() which will
be called before pcim_enable_device(). We can do this since PCI specification
requires class, device and vendor ID registers to be always present in the
configuration space.

As an example what happens before this patch applied
(These are some debug prints, don't search for them in kernel sources):

	serial 0000:00:04.1: Mapped GSI28 to IRQ28
	serial 0000:00:04.2: Mapped GSI29 to IRQ29
	serial 0000:00:04.3: Mapped GSI54 to IRQ54
	8250_mid 0000:00:04.1: Mapped GSI28 to IRQ28
	8250_mid 0000:00:04.2: Mapped GSI29 to IRQ29
	8250_mid 0000:00:04.3: Mapped GSI54 to IRQ54

After we will have just last three lines out of above.

	8250_mid 0000:00:04.1: Mapped GSI28 to IRQ28
	8250_mid 0000:00:04.2: Mapped GSI29 to IRQ29
	8250_mid 0000:00:04.3: Mapped GSI54 to IRQ54

While here, correct a value of error code mentioned in the comment of
serial_pci_guess_board().
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

First 16 bits in the flags field are user-visible except
UPF_NO_TXEN_TEST. To keep it clean we introduce internal quirks and move
UPF_NO_TXEN_TEST to them. Rename the constant to UPQ_NO_TXEN_TEST to
distinguish with port flags. Users are converted accordingly.

The quirks field might be extended later to hold the additional ones.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

upf_t is a bitwise defined type and any assignment from different, but
compatible, types makes static analyzer unhappy.

drivers/tty/serial/serial_core.c:793:29: warning: incorrect type in assignment (different base types)
drivers/tty/serial/serial_core.c:793:29:    expected int [signed] flags
drivers/tty/serial/serial_core.c:793:29:    got restricted upf_t [usertype] flags
drivers/tty/serial/serial_core.c:867:19: warning: incorrect type in assignment (different base types)
drivers/tty/serial/serial_core.c:867:19:    expected restricted upf_t [usertype] new_flags
drivers/tty/serial/serial_core.c:867:19:    got int [signed] flags

Enforce corresponding types when upf_t being assigned.

Note, we need __force attribute due to the scope of variable. It's being
used in user space with plain old type while kernel uses bitwise one.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The earlycon would be alive outside the init code in these cases:
1/ we have keep_bootcon in cmdline.
2/ we don't have a real console to switch to.

So remove the __init marking to avoid invalid memory access.
Signed-off-by: NJeffy Chen <jeffy.chen@rock-chips.com>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The earlycon would be alive outside the init code in these cases:
1/ we have keep_bootcon in cmdline.
2/ we don't have a real console to switch to.

So remove the __init marking to avoid invalid memory access.
Signed-off-by: NJeffy Chen <jeffy.chen@rock-chips.com>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The earlycon would be alive outside the init code in these cases:
1/ we have keep_bootcon in cmdline.
2/ we don't have a real console to switch to.

So remove the __init marking to avoid invalid memory access.
Signed-off-by: NJeffy Chen <jeffy.chen@rock-chips.com>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The earlycon would be alive outside the init code in these cases:
1/ we have keep_bootcon in cmdline.
2/ we don't have a real console to switch to.

So remove the __init marking to avoid invalid memory access.
Signed-off-by: NJeffy Chen <jeffy.chen@rock-chips.com>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The earlycon would be alive outside the init code in these cases:
1/ we have keep_bootcon in cmdline.
2/ we don't have a real console to switch to.

So remove the __init marking to avoid invalid memory access.
Signed-off-by: NJeffy Chen <jeffy.chen@rock-chips.com>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There are several error handling paths in aspeed_vuart_probe(),
where sysfs group is left unremoved. The patch fixes them.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: NAlexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

On Spreadtrum's serial device, nearly all of interrupts would be cleared
by hardware except timeout interrupt.  This patch removed the operation
of clearing all interrupt in irq handler, instead added an if statement
to check if the timeout interrupt is supposed to be cleared.

Wrongly clearing timeout interrupt would lead to uart data stay in rx
fifo, that means the driver cannot read them out anymore.
Signed-off-by: NLanqing Liu <lanqing.liu@spreadtrum.com>
Signed-off-by: NChunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The wait queue was only initialized and then checked if it contains
active jobs but a job is never added. The last real user was removed
with commit 9d297239 ("serial: imx-serial - update UART IMX driver
to use cyclic DMA").

Further there is no need to release the lock for the check if the port
should be woken up, (and IMHO there never was) so drop the unlock/lock
pair in dma_tx_callback(), too.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit a53e35db ("reset: Ensure drivers are explicit when requesting
reset lines") started to transition the reset control request API calls
to explicitly state whether the driver needs exclusive or shared reset
control behavior. Convert all drivers requesting exclusive resets to the
explicit API call so the temporary transition helpers can be removed.

No functional changes.

Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-tegra@vger.kernel.org
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit a53e35db ("reset: Ensure drivers are explicit when requesting
reset lines") started to transition the reset control request API calls
to explicitly state whether the driver needs exclusive or shared reset
control behavior. Convert all drivers requesting exclusive resets to the
explicit API call so the temporary transition helpers can be removed.

No functional changes.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-serial@vger.kernel.org
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

clk_disable_unprepare(info->clk) is missed in of_platform_serial_probe(),
while irq_dispose_mapping(port->irq) is missed in of_platform_serial_setup().

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: NAlexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.
Signed-off-by: NRob Herring <robh@kernel.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-serial@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>