diff options
| author | Christophe Leroy <christophe.leroy@c-s.fr> | 2018-09-14 13:32:50 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-10-04 03:01:49 +0300 |
| commit | 96d39a06a90eefbb4af649cd5e0628a4747a615b (patch) | |
| tree | 9fd7128c660d758739a92d756fc95b3b73f1a96e /drivers | |
| parent | c5347cd505fd0affa636e1ea0b39591b364c2d04 (diff) | |
| download | linux-96d39a06a90eefbb4af649cd5e0628a4747a615b.tar.xz | |
serial: cpm_uart: return immediately from console poll
commit be28c1e3ca29887e207f0cbcd294cefe5074bab6 upstream.
kgdb expects poll function to return immediately and
returning NO_POLL_CHAR when no character is available.
Fixes: f5316b4aea024 ("kgdb,8250,pl011: Return immediately from console poll")
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/tty/serial/cpm_uart/cpm_uart_core.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/tty/serial/cpm_uart/cpm_uart_core.c b/drivers/tty/serial/cpm_uart/cpm_uart_core.c index d3e3d42c0c12..0040c29f651a 100644 --- a/drivers/tty/serial/cpm_uart/cpm_uart_core.c +++ b/drivers/tty/serial/cpm_uart/cpm_uart_core.c @@ -1068,8 +1068,8 @@ static int poll_wait_key(char *obuf, struct uart_cpm_port *pinfo) /* Get the address of the host memory buffer. */ bdp = pinfo->rx_cur; - while (bdp->cbd_sc & BD_SC_EMPTY) - ; + if (bdp->cbd_sc & BD_SC_EMPTY) + return NO_POLL_CHAR; /* If the buffer address is in the CPM DPRAM, don't * convert it. @@ -1104,7 +1104,11 @@ static int cpm_get_poll_char(struct uart_port *port) poll_chars = 0; } if (poll_chars <= 0) { - poll_chars = poll_wait_key(poll_buf, pinfo); + int ret = poll_wait_key(poll_buf, pinfo); + + if (ret == NO_POLL_CHAR) + return ret; + poll_chars = ret; pollp = poll_buf; } poll_chars--; |