| Message ID | 20200809112259.7763-1-marek.vasut+renesas@gmail.com |
|---|---|
| State | Accepted |
| Commit | f5ba5c90d4b9c4d691a62eaca47dc095eefba8b1 |
| Delegated to: | Marek Vasut |
| Headers | show |
| Series | serial: sh: Improve FIFO empty check on RX | expand |
diff --git a/drivers/serial/serial_sh.c b/drivers/serial/serial_sh.c index 13b179f03d..e27d256574 100644 --- a/drivers/serial/serial_sh.c +++ b/drivers/serial/serial_sh.c @@ -116,7 +116,10 @@ static int serial_getc_check(struct uart_port *port) handle_error(port); if (sci_in(port, SCLSR) & SCxSR_ORER(port)) handle_error(port); - return status & (SCIF_DR | SCxSR_RDxF(port)); + status &= (SCIF_DR | SCxSR_RDxF(port)); + if (status) + return status; + return scif_rxfill(port); } static int sh_serial_getc_generic(struct uart_port *port)
If the SCIF is receiving data quickly enough, it may happen that the SCxSR_RDxF flag is cleared in sh_serial_getc_generic(), while the FIFO still contains data. If that happens, the serial_getc_check() reports no data in the FIFO as the flag is no longer set. Add one more check, if the SCxSR_RDxF is not set, read out the FIFO level and if there are still characters in the FIFO, permit reading them out. Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com> Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org> --- drivers/serial/serial_sh.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)