linux-stable.git/drivers/tty/serial, branch v3.18.54

serial: omap: suspend device on probe errors

2017-05-20T12:18:43+00:00

commit 77e6fe7fd2b7cba0bf2f2dc8cde51d7b9a35bf74 upstream.

Make sure to actually suspend the device before returning after a failed
(or deferred) probe.

Note that autosuspend must be disabled before runtime pm is disabled in
order to balance the usage count due to a negative autosuspend delay as
well as to make the final put suspend the device synchronously.

Fixes: 388bc2622680 ("omap-serial: Fix the error handling in the omap_serial probe")
Cc: Shubhrajyoti D 
Signed-off-by: Johan Hovold 
Acked-by: Tony Lindgren 
Signed-off-by: Greg Kroah-Hartman

serial: omap: fix runtime-pm handling on unbind

2017-05-20T12:18:43+00:00

commit 099bd73dc17ed77aa8c98323e043613b6e8f54fc upstream.

An unbalanced and misplaced synchronous put was used to suspend the
device on driver unbind, something which with a likewise misplaced
pm_runtime_disable leads to external aborts when an open port is being
removed.

Unhandled fault: external abort on non-linefetch (0x1028) at 0xfa024010
...
[] (serial_omap_set_mctrl) from [] (uart_update_mctrl+0x50/0x60)
[] (uart_update_mctrl) from [] (uart_shutdown+0xbc/0x138)
[] (uart_shutdown) from [] (uart_hangup+0x94/0x190)
[] (uart_hangup) from [] (__tty_hangup+0x404/0x41c)
[] (__tty_hangup) from [] (tty_vhangup+0x1c/0x20)
[] (tty_vhangup) from [] (uart_remove_one_port+0xec/0x260)
[] (uart_remove_one_port) from [] (serial_omap_remove+0x40/0x60)
[] (serial_omap_remove) from [] (platform_drv_remove+0x34/0x4c)

Fix this up by resuming the device before deregistering the port and by
suspending and disabling runtime pm only after the port has been
removed.

Also make sure to disable autosuspend before disabling runtime pm so
that the usage count is balanced and device actually suspended before
returning.

Note that due to a negative autosuspend delay being set in probe, the
unbalanced put would actually suspend the device on first driver unbind,
while rebinding and again unbinding would result in a negative
power.usage_count.

Fixes: 7e9c8e7dbf3b ("serial: omap: make sure to suspend device before remove")
Cc: Felipe Balbi 
Cc: Santosh Shilimkar 
Signed-off-by: Johan Hovold 
Acked-by: Tony Lindgren 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Detach low-level driver during PCI error recovery

2017-04-22T05:15:06+00:00

commit f209fa03fc9d131b3108c2e4936181eabab87416 upstream.

During a PCI error recovery, like the ones provoked by EEH in the ppc64
platform, all IO to the device must be blocked while the recovery is
completed.  Current 8250_pci implementation only suspends the port
instead of detaching it, which doesn't prevent incoming accesses like
TIOCMGET and TIOCMSET calls from reaching the device.  Those end up
racing with the EEH recovery, crashing it.  Similar races were also
observed when opening the device and when shutting it down during
recovery.

This patch implements a more robust IO blockage for the 8250_pci
recovery by unregistering the port at the beginning of the procedure and
re-adding it afterwards.  Since the port is detached from the uart
layer, we can be sure that no request will make through to the device
during recovery.  This is similar to the solution used by the JSM serial
driver.

I thank Peter Hurley  for valuable input on
this one over one year ago.

Signed-off-by: Gabriel Krisman Bertazi 
Signed-off-by: Greg Kroah-Hartman

tty/serial: atmel: fix race condition (TX+DMA)

2017-04-22T05:15:01+00:00

commit 31ca2c63fdc0aee725cbd4f207c1256f5deaabde upstream.

If uart_flush_buffer() is called between atmel_tx_dma() and
atmel_complete_tx_dma(), the circular buffer has been cleared, but not
atmel_port->tx_len.
That leads to a circular buffer overflow (dumping (UART_XMIT_SIZE -
atmel_port->tx_len) bytes).

Tested-by: Nicolas Ferre 
Signed-off-by: Richard Genoud 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Add MKS Tenta SCOM-0800 and SCOM-0801 cards

2017-04-18T05:55:49+00:00

commit 1c9c858e2ff8ae8024a3d75d2ed080063af43754 upstream.

The MKS Instruments SCOM-0800 and SCOM-0801 cards (originally by Tenta
Technologies) are 3U CompactPCI serial cards with 4 and 8 serial ports,
respectively.  The first 4 ports are implemented by an OX16PCI954 chip,
and the second 4 ports are implemented by an OX16C954 chip on a local
bus, bridged by the second PCI function of the OX16PCI954.  The ports
are jumper-selectable as RS-232 and RS-422/485, and the UARTs use a
non-standard oscillator frequency of 20 MHz (base_baud = 1250000).

Signed-off-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

serial: samsung: Fix ERR pointer dereference on deferred probe

2016-08-22T16:23:00+00:00

[ Upstream commit e51e4d8a185de90424b03f30181b35f29c46a25a ]

When the clk_get() of "uart" clock returns EPROBE_DEFER, the next re-probe
finishes with success but uses invalid (ERR_PTR) values.  This leads to
dereferencing of ERR_PTR stored under ourport->clk:

	12c30000.serial: Controller clock not found
	(...)
	12c30000.serial: ttySAC3 at MMIO 0x12c30000 (irq = 61, base_baud = 0) is a S3C6400/10
	Unable to handle kernel paging request at virtual address fffffdfb

	(clk_prepare) from [] (s3c24xx_serial_pm+0x20/0x128)
	(s3c24xx_serial_pm) from [] (uart_change_pm+0x38/0x40)
	(uart_change_pm) from [] (uart_add_one_port+0x31c/0x44c)
	(uart_add_one_port) from [] (s3c24xx_serial_probe+0x2a8/0x418)
	(s3c24xx_serial_probe) from [] (platform_drv_probe+0x50/0xb0)
	(platform_drv_probe) from [] (driver_probe_device+0x1f4/0x2b0)
	(driver_probe_device) from [] (bus_for_each_drv+0x44/0x8c)
	(bus_for_each_drv) from [] (__device_attach+0x9c/0x100)
	(__device_attach) from [] (bus_probe_device+0x84/0x8c)
	(bus_probe_device) from [] (deferred_probe_work_func+0x60/0x8c)
	(deferred_probe_work_func) from [] (process_one_work+0x120/0x328)
	(process_one_work) from [] (worker_thread+0x2c/0x4ac)
	(worker_thread) from [] (kthread+0xd8/0xf4)
	(kthread) from [] (ret_from_fork+0x14/0x3c)

The first unsuccessful clk_get() causes s3c24xx_serial_init_port() to
exit with failure but the s3c24xx_uart_port is left half-configured
(e.g. port->mapbase is set, clk contains ERR_PTR).  On next re-probe,
the function s3c24xx_serial_init_port() will exit early with success
because of configured port->mapbase and driver will use old values,
including the ERR_PTR as clock.

Fix this by cleaning the port->mapbase on error path so each re-probe
will initialize all of the port settings.

Fixes: 60e93575476f ("serial: samsung: enable clock before clearing pending interrupts during init")
Cc: 
Signed-off-by: Krzysztof Kozlowski 
Reviewed-by: Javier Martinez Canillas 
Tested-by: Javier Martinez Canillas 
Tested-by: Kevin Hilman 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

serial: samsung: Reorder the sequence of clock control when call s3c24xx_serial_set_termios()

2016-07-12T12:48:18+00:00

[ Upstream commit b8995f527aac143e83d3900ff39357651ea4e0f6 ]

This patch fixes the broken serial log when changing the clock source
of uart device. Before disabling the original clock source, this patch
enables the new clock source to protect the clock off state for a split second.

Signed-off-by: Chanwoo Choi 
Reviewed-by: Marek Szyprowski 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

8250: use callbacks to access UART_DLL/UART_DLM

2016-07-12T12:47:21+00:00

[ Upstream commit 0b41ce991052022c030fd868e03877700220b090 ]

Some UART HW has a single register combining UART_DLL/UART_DLM
(this was probably forgotten in the change that introduced the
callbacks, commit b32b19b8ffc05cbd3bf91c65e205f6a912ca15d9)

Fixes: b32b19b8ffc0 ("[SERIAL] 8250: set divisor register correctly ...")

Signed-off-by: Sebastian Frias 
Reviewed-by: Peter Hurley 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

QE-UART: add "fsl,t1040-ucc-uart" to of_device_id

2016-06-03T15:30:32+00:00

[ Upstream commit 11ca2b7ab432eb90906168c327733575e68d388f ]

New bindings use "fsl,t1040-ucc-uart" as the compatible for qe-uart.
So add it.

Signed-off-by: Zhao Qiang 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

tty: Add support for PCIe WCH382 2S multi-IO card

2016-03-02T20:19:13+00:00

[ Upstream commit 7dde55787b43a8f2b4021916db38d90c03a2ec64 ]

WCH382 2S board is a PCIe card with 2 DB9 COM ports detected as
Serial controller: Device 1c00:3253 (rev 10) (prog-if 05 [16850])

Signed-off-by: Jeremy McNicoll 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin