From 019dc9ea8d528eb3640bbba604e1e5a2f6994b1f Mon Sep 17 00:00:00 2001 From: Hui Wang Date: Wed, 24 Aug 2011 17:41:47 +0800 Subject: [PATCH] serial/imx: support to handle break character The imx UART hardware controller can identify BREAK character and the imx_set_termios() can accept BRKINT set by users, but current existing imx_rxint() can't pass BREAK character and TTY_BREAK to the tty layer as other serial drivers do (8250.c omap_serial.c). Here add code to handle BREAK character and pass it to tty layer. To detect error occurrence, i use URXD_ERR to replace (URXD_OVRRUN | URXD_FRMERR | ...) because any kind of error occurs, URXD_ERR will always be set to 1. I put the URXD_BRK to the first place to check since when BREAK error occurs, not only URXD_BRK is set to 1, but also URXD_PRERR and URXD_FRMERR are all set to 1. This arrangement can filter out fake parity and frame errors when BREAK error occurs. Signed-off-by: Hui Wang Acked-by: Sascha Hauer Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/imx.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 7e91b3d368cd..54ffdc6243f9 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -508,8 +508,10 @@ static irqreturn_t imx_rxint(int irq, void *dev_id) if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx)) continue; - if (rx & (URXD_PRERR | URXD_OVRRUN | URXD_FRMERR) ) { - if (rx & URXD_PRERR) + if (unlikely(rx & URXD_ERR)) { + if (rx & URXD_BRK) + sport->port.icount.brk++; + else if (rx & URXD_PRERR) sport->port.icount.parity++; else if (rx & URXD_FRMERR) sport->port.icount.frame++; @@ -524,7 +526,9 @@ static irqreturn_t imx_rxint(int irq, void *dev_id) rx &= sport->port.read_status_mask; - if (rx & URXD_PRERR) + if (rx & URXD_BRK) + flg = TTY_BREAK; + else if (rx & URXD_PRERR) flg = TTY_PARITY; else if (rx & URXD_FRMERR) flg = TTY_FRAME; -- 2.20.1