The error handler calls sci_rx_interrupt() to drain the receive FIFO if
an error condition happens.
However, if DMA is enabled on SCIFA or SCIFB, this will call
disable_irq_nosync() twice. Due to this imbalance, the receive interrupt
will never be re-enabled, and reception stops forever.
To fix this, restrict draining the FIFO to PIO mode, and just call
sci_receive_chars() directly.
Inspired by a patch from Yoshihiro Shimoda
<yoshihiro.shimoda.uh@xxxxxxxxxxx>.
Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
v3:
- New.
---
drivers/tty/serial/sh-sci.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 70e16f402e3108f4..82456fb09138dc2a 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -993,6 +993,7 @@ static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
static irqreturn_t sci_er_interrupt(int irq, void *ptr)
{
struct uart_port *port = ptr;
+ struct sci_port *s = to_sci_port(port);
/* Handle errors */
if (port->type == PORT_SCI) {
@@ -1003,7 +1004,8 @@ static irqreturn_t sci_er_interrupt(int irq, void *ptr)
}
} else {
sci_handle_fifo_overrun(port);
- sci_rx_interrupt(irq, ptr);
+ if (!s->chan_rx)
+ sci_receive_chars(ptr);
}
sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
--
1.9.1
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