From: Peng Fan Date: Tue, 29 Sep 2020 09:55:09 +0000 (+0800) Subject: tty: serial: fsl_lpuart: fix lpuart32_poll_get_char X-Git-Tag: v5.8.17~7 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3d53646d781b1f6008b637a78a9cd40e9ec86d1b;p=thirdparty%2Fkernel%2Fstable.git 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 --- diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 88d09aea706a9..f8ba7690efe31 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -680,7 +680,7 @@ 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);