linux-toradex.git/drivers/tty/serial, branch v3.4.72

serial/mxs-auart: increase time to wait for transmitter to become idle

2013-08-11T22:38:41+00:00

commit 079a036f4283e2b0e5c26080b8c5112bc0cc1831 upstream.

Without this patch the driver waits ~1 ms for the UART to become idle. At
115200n8 this time is (theoretically) enough to transfer 11.5 characters
(= 115200 bits/s / (10 Bits/char) * 1ms). As the mxs-auart has a fifo size
of 16 characters the clock is gated too early. The problem is worse for
lower baud rates.

This only happens to really shut down the transmitter in the middle of a
transfer if /dev/ttyAPPx isn't opened in userspace (e.g. by a getty) but
was at least once (because the bootloader doesn't disable the transmitter).

So increase the timeout to 20 ms which should be enough for 9600n8, too.
Moreover skip gating the clock if the timeout is elapsed.

Signed-off-by: Uwe Kleine-König 
Signed-off-by: Greg Kroah-Hartman

serial/mxs-auart: fix race condition in interrupt handler

2013-08-11T22:38:41+00:00

commit d970d7fe65adff5efe75b4a73c4ffc9be57089f7 upstream.

The handler needs to ack the pending events before actually handling them.
Otherwise a new event might come in after it it considered non-pending or
handled and is acked then without being handled. So this event is only
noticed when the next interrupt happens.

Without this patch an i.MX28 based machine running an rt-patched kernel
regularly hangs during boot.

Signed-off-by: Uwe Kleine-König 
Signed-off-by: Greg Kroah-Hartman

Revert "serial: 8250_pci: add support for another kind of NetMos Technology PCI 9835 Multi-I/O Controller"

2013-07-13T18:03:41+00:00

commit 828c6a102b1f2b8583fadc0e779c46b31d448f0b upstream.

This reverts commit 8d2f8cd424ca0b99001f3ff4f5db87c4e525f366.

As reported by Stefan, this device already works with the parport_serial
driver, so the 8250_pci driver should not also try to grab it as well.

Reported-by: Stefan Seyfried 
Cc: Wang YanQing 
Signed-off-by: Greg Kroah-Hartman

pch_uart: fix a deadlock when pch_uart as console

2013-07-03T17:59:05+00:00

commit 384e301e3519599b000c1a2ecd938b533fc15d85 upstream.

When we use pch_uart as system console like 'console=ttyPCH0,115200',
then 'send break' to it. We'll encounter the deadlock on a cpu/core,
with interrupts disabled on the core. When we happen to have all irqs
affinity to cpu0 then the deadlock on cpu0 actually deadlock whole
system.

In pch_uart_interrupt, we have spin_lock_irqsave(&priv->lock, flags)
then call pch_uart_err_ir when break is received. Then the call to
dev_err would actually call to pch_console_write then we'll run into
another spin_lock(&priv->lock), with interrupts disabled.

So in the call sequence lead by pch_uart_interrupt, we should be
carefully to call functions that will 'print message to console' only
in case the uart port is not being used as serial console.

Signed-off-by: Liang Li 
Cc: Yijing Wang 
Signed-off-by: Greg Kroah-Hartman

serial_core.c: add put_device() after device_find_child()

2013-05-08T02:51:53+00:00

commit 5a65dcc04cda41f4122aacc37a5a348454645399 upstream.

The serial core uses device_find_child() but does not drop the reference to
the retrieved child after using it. This patch add the missing put_device().

What I have done to test this issue.

I used a machine with an AMBA PL011 serial driver. I tested the patch on
next-20120408 because the last branch [next-20120415] does not boot on this
board.

For test purpose, I added some pr_info() messages to print the refcount
after device_find_child() (lines: 1937,2009), and after put_device()
(lines: 1947, 2021).

Boot the machine *without* put_device(). Then:

echo reboot > /sys/power/disk
echo disk > /sys/power/state
[   87.058575] uart_suspend_port:1937 refcount 4
[   87.058582] uart_suspend_port:1947 refcount 4
[   87.098083] uart_resume_port:2009refcount 5
[   87.098088] uart_resume_port:2021 refcount 5

echo disk > /sys/power/state
[  103.055574] uart_suspend_port:1937 refcount 6
[  103.055580] uart_suspend_port:1947 refcount 6
[  103.095322] uart_resume_port:2009 refcount 7
[  103.095327] uart_resume_port:2021 refcount 7

echo disk > /sys/power/state
[  252.459580] uart_suspend_port:1937 refcount 8
[  252.459586] uart_suspend_port:1947 refcount 8
[  252.499611] uart_resume_port:2009 refcount 9
[  252.499616] uart_resume_port:2021 refcount 9

The refcount continuously increased.

Boot the machine *with* this patch. Then:

echo reboot > /sys/power/disk
echo disk > /sys/power/state
[  159.333559] uart_suspend_port:1937 refcount 4
[  159.333566] uart_suspend_port:1947 refcount 3
[  159.372751] uart_resume_port:2009 refcount 4
[  159.372755] uart_resume_port:2021 refcount 3

echo disk > /sys/power/state
[  185.713614] uart_suspend_port:1937 refcount 4
[  185.713621] uart_suspend_port:1947 refcount 3
[  185.752935] uart_resume_port:2009 refcount 4
[  185.752940] uart_resume_port:2021 refcount 3

echo disk > /sys/power/state
[  207.458584] uart_suspend_port:1937 refcount 4
[  207.458591] uart_suspend_port:1947 refcount 3
[  207.498598] uart_resume_port:2009 refcount 4
[  207.498605] uart_resume_port:2021 refcount 3

The refcount correctly handled.

Signed-off-by: Federico Vaga 
Signed-off-by: Greg Kroah-Hartman

tty: atmel_serial_probe(): index of atmel_ports[] fix

2013-04-05T17:04:18+00:00

commit 503bded92da283b2f31d87e054c4c6d30c3c2340 upstream.

Index of atmel_ports[ATMEL_MAX_UART] should be smaller
than ATMEL_MAX_UART.

Signed-off-by: Pawel Wieczorkiewicz 
Acked-by: Nicolas Ferre 
Signed-off-by: Greg Kroah-Hartman

sunsu: Fix panic in case of nonexistent port at "console=ttySY" cmdline option

2013-03-28T19:11:52+00:00

[ Upstream commit cb29529ea0030e60ef1bbbf8399a43d397a51526 ]

If a machine has X (X < 4) sunsu ports and cmdline
option "console=ttySY" is passed, where X < Y <= 4,
than the following panic happens:

Unable to handle kernel NULL pointer dereference
TPC: 
RPC: 
I7: 
Call Trace:
 [0000000000453a38] register_console+0x378/0x3e0
 [0000000000576fa0] uart_add_one_port+0x2e0/0x340
 [000000000057af40] su_probe+0x160/0x2e0
 [00000000005b8a4c] platform_drv_probe+0xc/0x20
 [00000000005b6c2c] driver_probe_device+0x12c/0x220
 [00000000005b6da8] __driver_attach+0x88/0xa0
 [00000000005b4df4] bus_for_each_dev+0x54/0xa0
 [00000000005b5a54] bus_add_driver+0x154/0x260
 [00000000005b7190] driver_register+0x50/0x180
 [00000000006d250c] sunsu_init+0x18c/0x1e0
 [00000000006c2668] do_one_initcall+0xe8/0x160
 [00000000006c282c] kernel_init_freeable+0x12c/0x1e0
 [0000000000603764] kernel_init+0x4/0x100
 [0000000000405f64] ret_from_syscall+0x1c/0x2c
 [0000000000000000]           (null)

1)Fix the panic;
2)Increment registered port number every successful
probe.

Signed-off-by: Kirill Tkhai 
CC: David Miller 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tty: serial: fix typo "ARCH_S5P6450"

2013-03-20T20:04:59+00:00

commit 827aa0d36d486f359808c8fb931cf7a71011a09d upstream.

This could have been either ARCH_S5P64X0 or CPU_S5P6450. Looking at
commit 2555e663b367b8d555e76023f4de3f6338c28d6c ("ARM: S5P64X0: Add UART
serial support for S5P6450") - which added this typo - makes clear this
should be CPU_S5P6450.

Signed-off-by: Paul Bolle 
Acked-by: Kukjin Kim 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: add support for another kind of NetMos Technology PCI 9835 Multi-I/O Controller

2013-03-20T20:04:58+00:00

commit 8d2f8cd424ca0b99001f3ff4f5db87c4e525f366 upstream.

01:08.0 Communication controller: NetMos Technology PCI 9835 Multi-I/O Controller (rev 01)
	Subsystem: Device [1000:0012]
	Control: I/O+ Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- SERR- 
Signed-off-by: Greg Kroah-Hartman

tty: 8250_dw: Fix inverted arguments to serial_out in IRQ handler

2013-01-21T19:45:26+00:00

commit 68e56cb3a068f9c30971c6117fbbd1e32918e49e upstream.

Signed-off-by: Maxime Ripard 
Signed-off-by: Greg Kroah-Hartman