linux-stable.git/drivers/tty/serial, branch v4.14.40

earlycon: Use a pointer table to fix __earlycon_table stride

2018-05-01T19:58:24+00:00

commit dd709e72cb934eefd44de8d9969097173fbf45dc upstream.

Commit 99492c39f39f ("earlycon: Fix __earlycon_table stride") tried to fix
__earlycon_table stride by forcing the earlycon_id struct alignment to 32
and asking the linker to 32-byte align the __earlycon_table symbol.  This
fix was based on commit 07fca0e57fca92 ("tracing: Properly align linker
defined symbols") which tried a similar fix for the tracing subsystem.

However, this fix doesn't quite work because there is no guarantee that
gcc will place structures packed into an array format.  In fact, gcc 4.9
chooses to 64-byte align these structs by inserting additional padding
between the entries because it has no clue that they are supposed to be in
an array.  If we are unlucky, the linker will assign symbol
"__earlycon_table" to a 32-byte aligned address which does not correspond
to the 64-byte aligned contents of section "__earlycon_table".

To address this same problem, the fix to the tracing system was
subsequently re-implemented using a more robust table of pointers approach
by commits:
 3d56e331b653 ("tracing: Replace syscall_meta_data struct array with pointer array")
 654986462939 ("tracepoints: Fix section alignment using pointer array")
 e4a9ea5ee7c8 ("tracing: Replace trace_event struct array with pointer array")

Let's use this same "array of pointers to structs" approach for
EARLYCON_TABLE.

Fixes: 99492c39f39f ("earlycon: Fix __earlycon_table stride")
Signed-off-by: Daniel Kurtz 
Suggested-by: Aaron Durbin 
Reviewed-by: Rob Herring 
Tested-by: Guenter Roeck 
Reviewed-by: Guenter Roeck 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

tty: serial: exar: Relocate sleep wake-up handling

2018-04-26T09:02:11+00:00

[ Upstream commit c7e1b4059075c9e8eed101d7cc5da43e95eb5e18 ]

Exar sleep wake-up handling has been done on a per-channel basis by
virtue of INT0 being accessible from each channel's address space. I
believe this was initially done out of necessity, but now that Exar
devices have their own driver, we can do things more efficiently by
registering a dedicated INT0 handler at the PCI device level.

I see this change providing the following benefits:

    1. If more than one port is active, eliminates the redundant bus
       cycles for reading INT0 on every interrupt.
    2. This note associated with hooking in the per-channel handler in
       8250_port.c is resolved:
        /* Fixme: probably not the best place for this */

Cc: Matt Schulte 
Signed-off-by: Aaron Sierra 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

serial: 8250: Add Nuvoton NPCM UART

2018-04-08T12:26:30+00:00

commit f597fbce38d230af95384f4a04e0a13a1d0ad45d upstream.

The Nuvoton UART is almost compatible with the 8250 driver when probed
via the 8250_of driver, however it requires some extra configuration
at startup.

Reviewed-by: Rob Herring 
Signed-off-by: Joel Stanley 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Don't fail on multiport card class

2018-03-24T10:01:29+00:00

commit e7f3e99cb1a667d04d60d02957fbed58b50d4e5a upstream.

Do not fail on multiport cards in serial_pci_is_class_communication().

It restores behaviour for SUNIX multiport cards, that enumerated by
class and have a custom board data.

Moreover it allows users to reenumerate port-by-port from user space.

Fixes: 7d8905d06405 ("serial: 8250_pci: Enable device after we check black list")
Reported-by: Nikola Ciprich 
Signed-off-by: Andy Shevchenko 
Tested-by: Nikola Ciprich 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_dw: Disable clock on error

2018-03-24T10:01:23+00:00

[ Upstream commit 8af016aa5a27c6a2505460eb4d83f1e70c38dc43 ]

If there is no clock rate for uartclk defined, disable the previously
enabled clock again.

Found by Linux Driver Verification project (linuxtesting.org).

Fixes: 23f5b3fdd04e serial: 8250_dw: only get the clock rate in one place
Signed-off-by: Stefan Potyra 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

earlycon: add reg-offset to physical address before mapping

2018-03-19T07:42:47+00:00

commit 1f66dd36bb18437397ea0d7882c52f7e3c476e15 upstream.

It will get the wrong virtual address because port->mapbase is not added
the correct reg-offset yet. We have to update it before earlycon_map()
is called

Signed-off-by: Greentime Hu 
Acked-by: Arnd Bergmann 
Cc: Peter Hurley 
Cc: stable@vger.kernel.org
Fixes: 088da2a17619 ("of: earlycon: Initialize port fields from DT properties")
Acked-by: Rob Herring 
Signed-off-by: Greg Kroah-Hartman

serial: core: mark port as initialized in autoconfig

2018-03-19T07:42:46+00:00

commit 714569064adee3c114a2a6490735b94abe269068 upstream.

This is a followup on 44117a1d1732 ("serial: core: mark port as
initialized after successful IRQ change").
Nikola has been using autoconfig via setserial and reported a crash
similar to what I fixed in the earlier mentioned commit. Here I do the
same fixup for the autoconfig. I wasn't sure that this is the right
approach. Nikola confirmed that it fixes his crash.

Fixes: b3b576461864 ("tty: serial_core: convert uart_open to use tty_port_open")
Link: http://lkml.kernel.org/r/20180131072000.GD1853@localhost.localdomain
Reported-by: Nikola Ciprich 
Tested-by: Nikola Ciprich 
Cc: 
Signed-off-by: Sebastian Andrzej Siewior 
Tested-by: Nikola Ciprich 
Acked-by: Johan Hovold 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Add Brainboxes UC-260 4 port serial device

2018-03-19T07:42:46+00:00

commit 9f2068f35729948bde84d87a40d135015911345d upstream.

Add PCI ids for two variants of Brainboxes UC-260 quad port
PCI serial cards.

Suggested-by: Andy Shevchenko 
Signed-off-by: Nikola Ciprich 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

tty/serial: atmel: add new version check for usart

2018-03-19T07:42:45+00:00

commit fd63a8903a2c40425a9811c3371dd4d0f42c0ad3 upstream.

On our at91sam9260 based board the usart0 and usart1 ports report
their versions (ATMEL_US_VERSION) as 0x10302. This version is not
included in the current checks in the driver.

Signed-off-by: Jonas Danielsson 
Acked-by: Richard Genoud 
Acked-by: Nicolas Ferre 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: prevent lockup on full TTY buffers

2018-03-19T07:42:45+00:00

commit 7842055bfce4bf0170d0f61df8b2add8399697be upstream.

When the TTY buffers fill up to the configured maximum, a system lockup
occurs:

[  598.820128] INFO: rcu_preempt detected stalls on CPUs/tasks:
[  598.825796]  0-...!: (1 GPs behind) idle=5a6/2/0 softirq=1974/1974 fqs=1
[  598.832577]  (detected by 3, t=62517 jiffies, g=296, c=295, q=126)
[  598.838755] Task dump for CPU 0:
[  598.841977] swapper/0       R  running task        0     0      0 0x00000022
[  598.849023] Call trace:
[  598.851476]  __switch_to+0x98/0xb0
[  598.854870]            (null)

This can be prevented by doing a dummy read of the RX data register.

This issue affects both HSCIF and SCIF ports. Reported for R-Car H3 ES2.0;
reproduced and fixed on H3 ES1.1. Probably affects other R-Car platforms
as well.

Reported-by: Yoshihiro Shimoda 
Signed-off-by: Ulrich Hecht 
Reviewed-by: Geert Uytterhoeven 
Cc: stable 
Tested-by: Nguyen Viet Dung 
Signed-off-by: Greg Kroah-Hartman