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 <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Maciej W. Rozycki 2008-02-07 00:15:12 -08:00 committed by Linus Torvalds
parent 43d46ab1cd
commit 54c0f37e9a
2 changed files with 49 additions and 41 deletions

View File

@ -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;
@ -176,58 +177,57 @@ 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))
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;
if (dport->port.flags & UPF_SAK)
} 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 */
else if (status & DZ_PERR)
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;
}
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);
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])
tty_flip_buffer_push(dz_ports[i].port.info->tty);
@ -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);
}

View File

@ -33,6 +33,8 @@
#define DZ_FERR 0x2000 /* Frame error indicator */
#define DZ_PERR 0x1000 /* Parity error indicator */
#define DZ_BREAK 0x0800 /* BREAK event software flag */
#define LINE(x) ((x & DZ_LINE_MASK) >> 8) /* Get the line number
from the input buffer */
#define UCHAR(x) ((unsigned char)(x & DZ_RBUF_MASK))