Marek reports, that the -next commit 1788cf6a91d9 (tty: serial: switch
from circ_buf to kfifo) broke meson_uart and qcom_geni_serial. The
commit mistakenly advanced the kfifo twice: once by
uart_fifo_get()/kfifo_out() and second time by uart_xmit_advance().
To advance the fifo only once, drop the superfluous uart_xmit_advance()
from both.
To count the TX statistics properly, use uart_fifo_out() in
qcom_geni_serial (meson_uart_start_tx() already uses that).
I checked all other uses of uart_xmit_advance() and they appear correct:
either they are finishing DMA transfers or are after peek/linear_ptr
(i.e. they do not advance fifo).
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@xxxxxxxxxx>
Reported-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Cc: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
Cc: Kevin Hilman <khilman@xxxxxxxxxxxx>
Cc: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
Cc: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
---
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-amlogic@xxxxxxxxxxxxxxxxxxx
Cc: linux-arm-msm@xxxxxxxxxxxxxxx
---
drivers/tty/serial/meson_uart.c | 1 -
drivers/tty/serial/qcom_geni_serial.c | 4 +---
2 files changed, 1 insertion(+), 4 deletions(-)
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 4587ed4d4d5d..8eb586ac3b0d 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -162,7 +162,6 @@ static void meson_uart_start_tx(struct uart_port *port)
break;
writel(ch, port->membase + AML_UART_WFIFO);
- uart_xmit_advance(port, 1);
}
if (!kfifo_is_empty(&tport->xmit_fifo)) {
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 7814982f1921..2bd25afe0d92 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -855,7 +855,6 @@ static void qcom_geni_serial_send_chunk_fifo(struct uart_port *uport,
unsigned int chunk)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
- struct tty_port *tport = &uport->state->port;
unsigned int tx_bytes, remaining = chunk;
u8 buf[BYTES_PER_FIFO_WORD];
@@ -863,8 +862,7 @@ static void qcom_geni_serial_send_chunk_fifo(struct uart_port *uport,
memset(buf, 0, sizeof(buf));
tx_bytes = min(remaining, BYTES_PER_FIFO_WORD);
- tx_bytes = kfifo_out(&tport->xmit_fifo, buf, tx_bytes);
- uart_xmit_advance(uport, tx_bytes);
+ tx_bytes = uart_fifo_out(uport, buf, tx_bytes);
iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1);
--
2.44.0
