From 54c0f37e9a200d74ec43cffa6526d9ad17a388a7 Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Thu, 7 Feb 2008 00:15:12 -0800 Subject: dz: handle special conditions on reception correctly Handle the read and ignore status masks correctly. Handle the BREAK condition as expected: a framing error with a null character is a BREAK, any other framing error is a framing error indeed. Signed-off-by: Maciej W. Rozycki Cc: Jiri Slaby Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/serial/dz.c | 82 ++++++++++++++++++++++++++++------------------------- 1 file changed, 44 insertions(+), 38 deletions(-) (limited to 'drivers/serial/dz.c') diff --git a/drivers/serial/dz.c b/drivers/serial/dz.c index 656c342a80f8..ae3203b20134 100644 --- a/drivers/serial/dz.c +++ b/drivers/serial/dz.c @@ -166,6 +166,7 @@ static void dz_enable_ms(struct uart_port *port) */ static inline void dz_receive_chars(struct dz_port *dport_in) { + struct uart_port *uport; struct dz_port *dport; struct tty_struct *tty = NULL; struct uart_icount *icount; @@ -176,57 +177,56 @@ static inline void dz_receive_chars(struct dz_port *dport_in) while ((status = dz_in(dport_in, DZ_RBUF)) & DZ_DVAL) { dport = &dz_ports[LINE(status)]; - tty = dport->port.info->tty; /* point to the proper dev */ + uport = &dport->port; + tty = uport->info->tty; /* point to the proper dev */ ch = UCHAR(status); /* grab the char */ + flag = TTY_NORMAL; - icount = &dport->port.icount; + icount = &uport->icount; icount->rx++; - flag = TTY_NORMAL; - if (status & DZ_FERR) { /* frame error */ + if (unlikely(status & (DZ_OERR | DZ_FERR | DZ_PERR))) { + /* - * There is no separate BREAK status bit, so - * treat framing errors as BREAKs for Magic SysRq - * and SAK; normally, otherwise. + * There is no separate BREAK status bit, so treat + * null characters with framing errors as BREAKs; + * normally, otherwise. For this move the Framing + * Error bit to a simulated BREAK bit. */ - if (uart_handle_break(&dport->port)) - continue; - if (dport->port.flags & UPF_SAK) + if (!ch) { + status |= (status & DZ_FERR) >> + (ffs(DZ_FERR) - ffs(DZ_BREAK)); + status &= ~DZ_FERR; + } + + /* Handle SysRq/SAK & keep track of the statistics. */ + if (status & DZ_BREAK) { + icount->brk++; + if (uart_handle_break(uport)) + continue; + } else if (status & DZ_FERR) + icount->frame++; + else if (status & DZ_PERR) + icount->parity++; + if (status & DZ_OERR) + icount->overrun++; + + status &= uport->read_status_mask; + if (status & DZ_BREAK) flag = TTY_BREAK; - else + else if (status & DZ_FERR) flag = TTY_FRAME; - } else if (status & DZ_OERR) /* overrun error */ - flag = TTY_OVERRUN; - else if (status & DZ_PERR) /* parity error */ - flag = TTY_PARITY; - - /* keep track of the statistics */ - switch (flag) { - case TTY_FRAME: - icount->frame++; - break; - case TTY_PARITY: - icount->parity++; - break; - case TTY_OVERRUN: - icount->overrun++; - break; - case TTY_BREAK: - icount->brk++; - break; - default: - break; + else if (status & DZ_PERR) + flag = TTY_PARITY; + } - if (uart_handle_sysrq_char(&dport->port, ch)) + if (uart_handle_sysrq_char(uport, ch)) continue; - if ((status & dport->port.ignore_status_mask) == 0) { - uart_insert_char(&dport->port, - status, DZ_OERR, ch, flag); - lines_rx[LINE(status)] = 1; - } + uart_insert_char(uport, status, DZ_OERR, ch, flag); + lines_rx[LINE(status)] = 1; } for (i = 0; i < DZ_NB_PORT; i++) if (lines_rx[i]) @@ -556,11 +556,17 @@ static void dz_set_termios(struct uart_port *uport, struct ktermios *termios, dport->port.read_status_mask = DZ_OERR; if (termios->c_iflag & INPCK) dport->port.read_status_mask |= DZ_FERR | DZ_PERR; + if (termios->c_iflag & (BRKINT | PARMRK)) + dport->port.read_status_mask |= DZ_BREAK; /* characters to ignore */ uport->ignore_status_mask = 0; + if ((termios->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK)) + dport->port.ignore_status_mask |= DZ_OERR; if (termios->c_iflag & IGNPAR) dport->port.ignore_status_mask |= DZ_FERR | DZ_PERR; + if (termios->c_iflag & IGNBRK) + dport->port.ignore_status_mask |= DZ_BREAK; spin_unlock_irqrestore(&dport->port.lock, flags); } -- cgit v1.2.2