From 5e193ce443fecc955dc3160359c4f7abbc324ef7 Mon Sep 17 00:00:00 2001 From: Peng Fan Date: Tue, 29 Sep 2020 17:55:09 +0800 Subject: [PATCH] tty: serial: fsl_lpuart: fix lpuart32_poll_get_char commit 29788ab1d2bf26c130de8f44f9553ee78a27e8d5 upstream. The watermark is set to 1, so we need to input two chars to trigger RDRF using the original logic. With the new logic, we could always get the char when there is data in FIFO. Suggested-by: Fugang Duan Signed-off-by: Peng Fan Link: https://lore.kernel.org/r/20200929095509.21680-1-peng.fan@nxp.com Cc: stable Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/fsl_lpuart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 2daccb10ae2f3..4b9f422694779 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -563,7 +563,7 @@ static void lpuart32_poll_put_char(struct uart_port *port, unsigned char c) static int lpuart32_poll_get_char(struct uart_port *port) { - if (!(lpuart32_read(port, UARTSTAT) & UARTSTAT_RDRF)) + if (!(lpuart32_read(port, UARTWATER) >> UARTWATER_RXCNT_OFF)) return NO_POLL_CHAR; return lpuart32_read(port, UARTDATA); -- 2.47.3