From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: [PATCH 1/8] serial: st-asc: Ignore the parity error bit if 8-bit mode is enabled Date: Tue, 24 Jan 2017 13:43:03 +0000 Message-ID: <20170124134310.27512-2-lee.jones@linaro.org> References: <20170124134310.27512-1-lee.jones@linaro.org> Return-path: In-Reply-To: <20170124134310.27512-1-lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, jslaby-IBi9RG/b67k@public.gmane.org, linux-serial-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kernel-F5mvAk5X5gdBDgjK7y7TUQ@public.gmane.org, patrice.chotard-qxv4g6HH51o@public.gmane.org, Lee Jones List-Id: devicetree@vger.kernel.org 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." Signed-off-by: Lee Jones --- drivers/tty/serial/st-asc.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c index 379e5bd..69e6232 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)) { -- 2.10.2 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html