[PATCH v3 1/1] tty: serial: imx: allow breaks to be received when using dma
From: Uwe Kleine-König <hidden>
Date: 2018-02-20 19:59:44
Also in:
linux-serial
On Tue, Feb 20, 2018 at 10:20:37AM -0800, Troy Kisky wrote:
quoted hunk ↗ jump to hunk
This allows me to login after sending a break when service serial-getty at ttymxc0.service is running The "tty_insert_flip_char(port, 0, TTY_BREAK)" in clear_rx_errors fixes this by allowing the higher layers to see a break. Signed-off-by: Troy Kisky <redacted> Tested-by: Martin Hicks <redacted> --- v2: rebase only v3: change commit message as requested by Fabio, add tested-by --- drivers/tty/serial/imx.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-)diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 1d7ca382bc12..2eb8c4a20d68 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c@@ -927,7 +927,6 @@ static void dma_rx_callback(void *data) status = dmaengine_tx_status(chan, (dma_cookie_t)0, &state); if (status == DMA_ERROR) { - dev_err(sport->port.dev, "DMA transaction error.\n"); clear_rx_errors(sport); return; }@@ -1028,6 +1027,7 @@ static int start_rx_dma(struct imx_port *sport) static void clear_rx_errors(struct imx_port *sport) { + struct tty_port *port = &sport->port.state->port; unsigned int status_usr1, status_usr2; status_usr1 = readl(sport->port.membase + USR1);@@ -1036,12 +1036,18 @@ static void clear_rx_errors(struct imx_port *sport) if (status_usr2 & USR2_BRCD) { sport->port.icount.brk++; writel(USR2_BRCD, sport->port.membase + USR2); - } else if (status_usr1 & USR1_FRAMERR) { - sport->port.icount.frame++; - writel(USR1_FRAMERR, sport->port.membase + USR1); - } else if (status_usr1 & USR1_PARITYERR) { - sport->port.icount.parity++; - writel(USR1_PARITYERR, sport->port.membase + USR1); + if (tty_insert_flip_char(port, 0, TTY_BREAK) == 0) + sport->port.icount.buf_overrun++; + tty_flip_buffer_push(port);
I think this needs to call uart_handle_break() as imx_rxint() does. Not sure how to properly handle SYSRQ in the dma case though.
+ } else {
+ dev_err(sport->port.dev, "DMA transaction error.\n");
+ if (status_usr1 & USR1_FRAMERR) {
+ sport->port.icount.frame++;
+ writel(USR1_FRAMERR, sport->port.membase + USR1);
+ } else if (status_usr1 & USR1_PARITYERR) {
+ sport->port.icount.parity++;
+ writel(USR1_PARITYERR, sport->port.membase + USR1);
+ }
}
if (status_usr2 & USR2_ORE) {
--
2.14.1
-- Pengutronix e.K. | Uwe Kleine-K?nig | Industrial Linux Solutions | http://www.pengutronix.de/ |