Call uart_write_wakeup() after writing the hardware FIFO and updateing the FIFO pointers. This fixes high latency and jitter on PPP over Serial links. Reported-by: Jun Shih <Jun.Shih@xxxxxxxxx> Tested-by: Jun Shih <Jun.Shih@xxxxxxxxx> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxx> --- drivers/tty/serial/men_z135_uart.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/men_z135_uart.c b/drivers/tty/serial/men_z135_uart.c index c9d1854..30e9e60 100644 --- a/drivers/tty/serial/men_z135_uart.c +++ b/drivers/tty/serial/men_z135_uart.c @@ -308,9 +308,6 @@ static void men_z135_handle_tx(struct men_z135_port *uart) if (port->x_char) goto out; - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); - /* calculate bytes to copy */ qlen = uart_circ_chars_pending(xmit); if (qlen <= 0) @@ -357,6 +354,9 @@ static void men_z135_handle_tx(struct men_z135_port *uart) port->icount.tx += n; + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + irq_en: if (!uart_circ_empty(xmit)) men_z135_reg_set(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
