diff options
| author | Ian Jamison <[email protected]> | 2017-08-28 09:02:29 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <[email protected]> | 2017-08-28 20:51:22 +0200 |
| commit | 5aabd3b0077e0577f60a1ca6b8bdad62f23353d8 (patch) | |
| tree | 37925cc552690d5c32604e8d06d30ad061422f61 | |
| parent | 81b289cc14ba349cc4707cf664aa1c72d7dff1d7 (diff) | |
serial: imx: Avoid post-PIO cleanup if TX DMA is started
The imx_transmit_buffer function should return if TX DMA has already
been started and not just skip over the buffer PIO write loop. (Which
did fix the initial problem, but could have unintentional side-effects)
Tested on an i.MX6Q board with half-duplex RS-485 and with RS-232.
Cc: Clemens Gruber <[email protected]>
Cc: Uwe-Kleine König <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Fabio Estevam <[email protected]>
Fixes: 514ab34dbad6 ("serial: imx: Prevent TX buffer PIO write when a DMA has been started")
Signed-off-by: Ian Jamison <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
| -rw-r--r-- | drivers/tty/serial/imx.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index d879a9b86424..dfeff3951f93 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -457,7 +457,10 @@ static inline void imx_transmit_buffer(struct imx_port *sport) } } - while (!uart_circ_empty(xmit) && !sport->dma_is_txing && + if (sport->dma_is_txing) + return; + + while (!uart_circ_empty(xmit) && !(readl(sport->port.membase + uts_reg(sport)) & UTS_TXFULL)) { /* send xmit->buf[xmit->tail] * out the port here */ |