linux-toradex.git/drivers/tty/serial/8250, branch v4.17

Merge 4.16-rc6 into tty-next

2018-03-20T10:27:18+00:00

We want the serial/tty fixes in here as well.

Signed-off-by: Greg Kroah-Hartman

8250-men-mcb: add support for 16z025 and 16z057

2018-03-15T17:12:55+00:00

Add support for two MEN UARTs (16z025 and 16z057) to the
8250_men_mcb driver.
The 16z025 consists of up to four ports, the 16z057 has
exactly four ports. Apart from that, all of them share the
Port settings.

Signed-off-by: Michael Moese 
Reported-by: Ben Turner 
Tested-by: Ben Turner 
Signed-off-by: Greg Kroah-Hartman

serial: 8250: Add Nuvoton NPCM UART

2018-03-09T19:01:19+00:00

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_dw: Switch to use acpi_dev_present()

2018-03-09T18:24:38+00:00

Special settings for APMC0D08 are applied when device is present
in the system. To check its presence we may use acpi_dev_present()
instead of current open coded variant.

Cc: Feng Kan 
Signed-off-by: Andy Shevchenko 
Signed-off-by: Greg Kroah-Hartman

serial, pci_ids: Move duplicate IDs to PCI IDs database

2018-02-28T14:33:04+00:00

PCI ID database is for IDs used across several drivers.
Here is the case for SUNIX combo cards.

No functional change intended.

Signed-off-by: Andy Shevchenko 
Signed-off-by: Greg Kroah-Hartman

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

2018-02-28T12:48:21+00:00

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

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

2018-02-28T12:48:21+00:00

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: Allow TX FIFO to drain before writing to UART_LCR

2018-02-28T12:40:22+00:00

An issue has been observed on the Marvell Armada 38x serial port.

Writes to UART_LCR can result in characters that are currently held in the
TX FIFO being lost rather than sent, even if the userspace process has
attempted to flush them.

This is most visible when using the "resize" command (tested on Busybox),
where we have observed the escape code for restoring cursor position
becoming mangled.

Signed-off-by: Joshua Scott 
Signed-off-by: Greg Kroah-Hartman

serial: 8250: 8250_omap: Fix throttling when DMA is enabled

2018-02-28T12:40:22+00:00

omap_8250_throttle() is called when tty RX buffer is about to overflow
and can no longer keep up with the rate at which UART is receiving data.
So, the expectation of this callback, is that UART stops RX and asserts
HW flow control to signal the sender to stop sending more data.
omap_8250_throttle() disables RX FIFO interrupts thus FIFO is no longer
serviced, leading to assertion of flow control once RX FIFO is full.
But, this does not work when DMA is enabled as driver keeps queuing new
RX DMA request in completion handler without brothering about throttling
request made by the higher layer.
This patch introduces a flag that can be used to determine whether or
not to queue next RX DMA request based on throttling request.

Without this patch, tty buffer overflows are reported at higher
baudrates.

Signed-off-by: Vignesh R 
Signed-off-by: Greg Kroah-Hartman

serial: 8250: Don't service RX FIFO if interrupts are disabled

2018-02-28T12:40:22+00:00

Currently, data in RX FIFO is read based on UART_LSR register state even
if RDI and RLSI interrupts are disabled in UART_IER register.
This is because when IRQ handler is called due to TX FIFO empty event,
RX FIFO is serviced based on UART_LSR register status instead of
UART_IIR status. This defeats the purpose of disabling UART RX
FIFO interrupts during throttling(see, omap_8250_throttle()) as IRQ
handler continues to drain UART RX FIFO resulting in overflow of buffer
at tty layer.
Fix this by making sure that driver drains UART RX FIFO only when
UART_IIR_RDI is set along with UART_LSR_BI or UART_LSR_DR bits.

Signed-off-by: Vignesh R 
Signed-off-by: Greg Kroah-Hartman