diff options
| author |   Lee Jones <lee.jones@linaro.org> | 2017-02-03 10:23:10 +0000 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-02-06 09:47:52 +0100 |
| commit | 5ab066e5465b2984a45e205f33896b2ec1620c37 (patch) | |
| tree | 454dc7b7d1dcf44dc47107b1fe751c66bbe7cba9 /drivers/tty/serial/st-asc.c | |
| parent | serial: 8250_pci: Add MKS Tenta SCOM-0800 and SCOM-0801 cards (diff) | |
| download | linux-dev-5ab066e5465b2984a45e205f33896b2ec1620c37.tar.xz linux-dev-5ab066e5465b2984a45e205f33896b2ec1620c37.zip | |
serial: st-asc: Ignore the parity error bit if 8-bit mode is enabled
The datasheet states:
"If the MODE field selects an 8-bit frame then this [parity error] bit
is undefined. Software should ignore this bit when reading 8-bit frames."
Acked-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/st-asc.c')
| -rw-r--r-- | drivers/tty/serial/st-asc.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c index 379e5bd37df9..69e62326723d 100644 --- a/drivers/tty/serial/st-asc.c +++ b/drivers/tty/serial/st-asc.c @@ -287,9 +287,19 @@ static void asc_transmit_chars(struct uart_port *port) static void asc_receive_chars(struct uart_port *port) { struct tty_port *tport = &port->state->port; - unsigned long status; + unsigned long status, mode; unsigned long c = 0; char flag; + bool ignore_pe = false; + + /* + * Datasheet states: If the MODE field selects an 8-bit frame then + * this [parity error] bit is undefined. Software should ignore this + * bit when reading 8-bit frames. + */ + mode = asc_in(port, ASC_CTL) & ASC_CTL_MODE_MSK; + if (mode == ASC_CTL_MODE_8BIT || mode == ASC_CTL_MODE_8BIT_PAR) + ignore_pe = true; if (port->irq_wake) pm_wakeup_event(tport->tty->dev, 0); @@ -299,8 +309,8 @@ static void asc_receive_chars(struct uart_port *port) flag = TTY_NORMAL; port->icount.rx++; - if ((c & (ASC_RXBUF_FE | ASC_RXBUF_PE)) || - status & ASC_STA_OE) { + if (status & ASC_STA_OE || c & ASC_RXBUF_FE || + (c & ASC_RXBUF_PE && !ignore_pe)) { if (c & ASC_RXBUF_FE) { if (c == (ASC_RXBUF_FE | ASC_RXBUF_DUMMY_RX)) { |