The LPUART Status Register needs to be cleared when closing the uart
port to get a clean environment when reopening the uart.
Fixes:
380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support")
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20221125101953.18753-4-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
spin_lock_irqsave(&port->lock, flags);
+ /* clear status */
+ temp = lpuart32_read(&sport->port, UARTSTAT);
+ lpuart32_write(&sport->port, temp, UARTSTAT);
+
/* disable Rx/Tx DMA */
temp = lpuart32_read(port, UARTBAUD);
temp &= ~(UARTBAUD_TDMAE | UARTBAUD_RDMAE);