From: delisun delisun@pateo.com.cn
[ Upstream commit 032d5a71ed378ffc6a2d41a187d8488a4f9fe415 ]
Clearing the RX FIFO will cause data loss. Copy the pl011_enabl_interrupts implementation, and remove the clear interrupt and FIFO part of the code.
Fixes: 211565b10099 ("serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottle") Signed-off-by: delisun delisun@pateo.com.cn Reviewed-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Link: https://lore.kernel.org/r/20221110020108.7700-1-delisun@pateo.com.cn Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/serial/amba-pl011.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 72c2a978cf61..c211a1e92db7 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1831,8 +1831,17 @@ static void pl011_enable_interrupts(struct uart_amba_port *uap) static void pl011_unthrottle_rx(struct uart_port *port) { struct uart_amba_port *uap = container_of(port, struct uart_amba_port, port); + unsigned long flags;
- pl011_enable_interrupts(uap); + spin_lock_irqsave(&uap->port.lock, flags); + + uap->im = UART011_RTIM; + if (!pl011_dma_rx_running(uap)) + uap->im |= UART011_RXIM; + + pl011_write(uap->im, uap, REG_IMSC); + + spin_unlock_irqrestore(&uap->port.lock, flags); }
static int pl011_startup(struct uart_port *port)