linux-stable.git/drivers/tty/serial, branch v4.11.2

tty: pl011: use "qdf2400_e44" as the earlycon name for QDF2400 E44

2017-05-20T12:49:50+00:00

commit 5a0722b898f851b9ef108ea7babc529e4efc773d upstream.

Define a new early console name for Qualcomm Datacenter Technologies
QDF2400 SOCs affected by erratum 44, instead of piggy-backing on "pl011".
Previously, to enable traditional (non-SPCR) earlycon, the documentation
said to specify "earlycon=pl011,,qdf2400_e44", but the code was
broken and this didn't actually work.

So instead, the method for specifying the E44 work-around with traditional
earlycon is "earlycon=qdf2400_e44,".  Both methods of earlycon
are now enabled with the same function.

Fixes: e53e597fd4c4 ("tty: pl011: fix earlycon work-around for QDF2400 erratum 44")
Signed-off-by: Timur Tabi 
Tested-by: Shanker Donthineni 
Signed-off-by: Greg Kroah-Hartman

serial: omap: suspend device on probe errors

2017-05-20T12:49:50+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

2017-05-20T12:49:50+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: samsung: Add missing checks for dma_map_single failure

2017-05-20T12:49:49+00:00

commit 500fcc08a32bfd54f11951ba81530775df15c474 upstream.

This patch adds missing checks for dma_map_single() failure and proper error
reporting. Although this issue was harmless on ARM architecture, it is always
good to use the DMA mapping API in a proper way. This patch fixes the following
DMA API debug warning:

WARNING: CPU: 1 PID: 3785 at lib/dma-debug.c:1171 check_unmap+0x8a0/0xf28
dma-pl330 121a0000.pdma: DMA-API: device driver failed to check map error[device address=0x000000006e0f9000] [size=4096 bytes] [mapped as single]
Modules linked in:
CPU: 1 PID: 3785 Comm: (agetty) Tainted: G        W       4.11.0-rc1-00137-g07ca963-dirty #59
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[] (unwind_backtrace) from [] (show_stack+0x20/0x24)
[] (show_stack) from [] (dump_stack+0x84/0xa0)
[] (dump_stack) from [] (__warn+0x14c/0x180)
[] (__warn) from [] (warn_slowpath_fmt+0x48/0x50)
[] (warn_slowpath_fmt) from [] (check_unmap+0x8a0/0xf28)
[] (check_unmap) from [] (debug_dma_unmap_page+0x98/0xc8)
[] (debug_dma_unmap_page) from [] (s3c24xx_serial_shutdown+0x314/0x52c)
[] (s3c24xx_serial_shutdown) from [] (uart_port_shutdown+0x54/0x88)
[] (uart_port_shutdown) from [] (uart_shutdown+0xd4/0x110)
[] (uart_shutdown) from [] (uart_hangup+0x9c/0x208)
[] (uart_hangup) from [] (__tty_hangup+0x49c/0x634)
[] (__tty_hangup) from [] (tty_ioctl+0xc88/0x16e4)
[] (tty_ioctl) from [] (do_vfs_ioctl+0xc4/0xd10)
[] (do_vfs_ioctl) from [] (SyS_ioctl+0x7c/0x8c)
[] (SyS_ioctl) from [] (ret_fast_syscall+0x0/0x3c)

Reported-by: Seung-Woo Kim 
Fixes: 62c37eedb74c8 ("serial: samsung: add dma reqest/release functions")
Signed-off-by: Marek Szyprowski 
Reviewed-by: Bartlomiej Zolnierkiewicz 
Reviewed-by: Shuah Khan 
Signed-off-by: Greg Kroah-Hartman

serial: samsung: Use right device for DMA-mapping calls

2017-05-20T12:49:49+00:00

commit 768d64f491a530062ddad50e016fb27125f8bd7c upstream.

Driver should provide its own struct device for all DMA-mapping calls instead
of extracting device pointer from DMA engine channel. Although this is harmless
from the driver operation perspective on ARM architecture, it is always good
to use the DMA mapping API in a proper way. This patch fixes following DMA API
debug warning:

WARNING: CPU: 0 PID: 0 at lib/dma-debug.c:1241 check_sync+0x520/0x9f4
samsung-uart 12c20000.serial: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x000000006df0f580] [size=64 bytes]
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.11.0-rc1-00137-g07ca963 #51
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[] (unwind_backtrace) from [] (show_stack+0x20/0x24)
[] (show_stack) from [] (dump_stack+0x84/0xa0)
[] (dump_stack) from [] (__warn+0x14c/0x180)
[] (__warn) from [] (warn_slowpath_fmt+0x48/0x50)
[] (warn_slowpath_fmt) from [] (check_sync+0x520/0x9f4)
[] (check_sync) from [] (debug_dma_sync_single_for_device+0x88/0xc8)
[] (debug_dma_sync_single_for_device) from [] (s3c24xx_serial_start_tx_dma+0x100/0x2f8)
[] (s3c24xx_serial_start_tx_dma) from [] (s3c24xx_serial_tx_chars+0x198/0x33c)

Reported-by: Seung-Woo Kim 
Fixes: 62c37eedb74c8 ("serial: samsung: add dma reqest/release functions")
Signed-off-by: Marek Szyprowski 
Reviewed-by: Bartlomiej Zolnierkiewicz 
Reviewed-by: Krzysztof Kozlowski 
Reviewed-by: Shuah Khan 
Signed-off-by: Greg Kroah-Hartman

tty: pl011: fix earlycon work-around for QDF2400 erratum 44

2017-04-01T09:07:29+00:00

The work-around for the Qualcomm Datacenter Technologies QDF2400
erratum 44 sets the "qdf2400_e44_present" global variable if the
work-around is needed.  However, this check does not happen until after
earlycon is initialized, which means the work-around is not
used, and the console hangs as soon as it displays one character.

Fixes: d8a4995bcea1 ("tty: pl011: Work around QDF2400 E44 stuck BUSY bit")
Signed-off-by: Timur Tabi 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_EXAR: fix duplicate Kconfig text and add missing help text

2017-03-31T15:26:20+00:00

In commit d0aeaa83f0b0f7a92615bbdd6b1f96812f7dcfd2 ("serial: exar:
split out the exar code from 8250_pci") the exar driver got its own
Kconfig.  However the text for the new option was never changed from
the original 8250_PCI text, and hence it appears confusing when you
get asked the same question twice:

  8250/16550 PCI device support (SERIAL_8250_PCI) [Y/n/m/?] (NEW)
    8250/16550 PCI device support (SERIAL_8250_EXAR) [Y/n/m] (NEW)

Adding to the confusion, is that there is no help text for this new
option to indicate it is specific to a certain family of cards.

Fix both issues at the same time, as well as the space vs. tab issues
introduced in the same commit.

Fixes: d0aeaa83f0b0 ("serial: exar: split out the exar code from 8250_pci")
Cc: Jiri Slaby 
Cc: linux-serial@vger.kernel.org
Signed-off-by: Paul Gortmaker 
Acked-by: Sudip Mukherjee 
Reviewed-by: Andy Shevchenko 
Signed-off-by: Greg Kroah-Hartman

tty/serial: atmel: fix TX path in atmel_console_write()

2017-03-31T15:26:20+00:00

A side effect of 89d8232411a8 ("tty/serial: atmel_serial: BUG: stop DMA
from transmitting in stop_tx") is that the console can be called with
TX path disabled. Then the system would hang trying to push charecters
out in atmel_console_putchar().

Signed-off-by: Nicolas Ferre 
Fixes: 89d8232411a8 ("tty/serial: atmel_serial: BUG: stop DMA from transmitting
in stop_tx")
Cc: stable 	#4.4+
Acked-by: Richard Genoud 
Signed-off-by: Greg Kroah-Hartman

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

2017-03-31T15:26:19+00:00

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 
Cc: stable  # 3.12+
Signed-off-by: Greg Kroah-Hartman

serial: mxs-auart: Fix baudrate calculation

2017-03-31T15:26:19+00:00

The reference manual for the i.MX28 recommends to calculate the divisor
as

	divisor = (UARTCLK * 32) / baud rate, rounded to the nearest integer

, so let's do this. For a typical setup of UARTCLK = 24 MHz and baud
rate = 115200 this changes the divisor from 6666 to 6667 and so the
actual baud rate improves from 115211.521 Bd (error ≅ 0.01 %) to
115194.240 Bd (error ≅ 0.005 %).

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