From: Pali Rohár Date: Sat, 11 Sep 2021 13:20:17 +0000 (+0200) Subject: serial: mvebu-uart: fix driver's tx_empty callback X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=503b2e01af0ef5106d6a32577d85e470cd956877;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git serial: mvebu-uart: fix driver's tx_empty callback commit 74e1eb3b4a1ef2e564b4bdeb6e92afe844e900de upstream. Driver's tx_empty callback should signal when the transmit shift register is empty. So when the last character has been sent. STAT_TX_FIFO_EMP bit signals only that HW transmit FIFO is empty, which happens when the last byte is loaded into transmit shift register. STAT_TX_EMP bit signals when the both HW transmit FIFO and transmit shift register are empty. So replace STAT_TX_FIFO_EMP check by STAT_TX_EMP in mvebu_uart_tx_empty() callback function. Fixes: 30530791a7a0 ("serial: mvebu-uart: initial support for Armada-3700 serial port") Cc: stable Signed-off-by: Pali Rohár Link: https://lore.kernel.org/r/20210911132017.25505-1-pali@kernel.org Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c index a10e4aa9e18e..ffd454e4bacf 100644 --- a/drivers/tty/serial/mvebu-uart.c +++ b/drivers/tty/serial/mvebu-uart.c @@ -108,7 +108,7 @@ static unsigned int mvebu_uart_tx_empty(struct uart_port *port) st = readl(port->membase + UART_STAT); spin_unlock_irqrestore(&port->lock, flags); - return (st & STAT_TX_FIFO_EMP) ? TIOCSER_TEMT : 0; + return (st & STAT_TX_EMP) ? TIOCSER_TEMT : 0; } static unsigned int mvebu_uart_get_mctrl(struct uart_port *port)