On 2/20/2018 11:59 AM, Uwe Kleine-König wrote:
> On Tue, Feb 20, 2018 at 10:20:37AM -0800, Troy Kisky wrote:
>> This allows me to login after sending a break when service
>> serial-getty@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 <troy.kisky@xxxxxxxxxxxxxxxxxxx>
>> Tested-by: Martin Hicks <mort@xxxxxxxx>
>>
>> ---
>> 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.
>
SYSRQ is only for the console port, and console port is never dma. But UPF_SAK may be
an issue. I don't know enough about "Secure Attention Key" to say.
Should I add uart_handle_break anyway ?
>> + } 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
>>
>>
>
--
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
