Hello Hector, On Tue, Oct 01, 2013 at 06:18:35PM +0200, Hector Palacios wrote: > The shutdown function was not waiting for the DMA buffer to flush > before disabling the AUART. This lead to many bytes not being > transferred (specially at low baudrates), as they were still in the > DMA buffer when the AUART was shutdown. > This patch also adds the check for the BUSY flag. > > Signed-off-by: Hector Palacios <hector.palacios@xxxxxxxx> > > https://jira.digi.com/browse/DEL-616 What is this? This isn't available in public DNS. > --- > drivers/tty/serial/mxs-auart.c | 16 +++++++++++++++- > 1 file changed, 15 insertions(+), 1 deletion(-) > > diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c > index f85b8e6..0d8b2ca 100644 > --- a/drivers/tty/serial/mxs-auart.c > +++ b/drivers/tty/serial/mxs-auart.c > @@ -750,12 +750,26 @@ static int mxs_auart_startup(struct uart_port *u) > return 0; > } > > +static unsigned int mxs_auart_tx_empty(struct uart_port *u); > + > static void mxs_auart_shutdown(struct uart_port *u) > { > struct mxs_auart_port *s = to_auart_port(u); > + unsigned int to; > + > + if (auart_dma_enabled(s)) { > + /* Wait enough time to flush DMA buffer completely */ > + to = u->timeout * UART_XMIT_SIZE / u->fifosize; u->timeout is the time needed to send one char, right? UART_XMIT_SIZE is the size of the circular buffer, fifosize is the size of the fifo. I don't get what you get by dividing by the fifosize. I would have expected something like: u->timeout * min(UART_XMIT_SIZE, u->fifosize) Can you explain, maybe in a comment along the code for the next person not understanding? I wonder if the individual driver is the right place this must be fixed in or if there should be (or even exists) some help form the serial framework?! Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ | -- 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
